2013-07-10 09:29:24

by Jonas Jensen

Subject: [PATCH] mmc: sdhci-moxart: Add MOXA ART SDHCI driver

Add SDHCI driver for MOXA ART SoCs.

Signed-off-by: Jonas Jensen <[email protected]>
---

Notes:
Applies to next-20130703

I know this is a large chunk and there are many pitfalls with
the controller. I give you my word it does work / seem to be stable,
with or without DMA. Any feedback is appreciated.

Tested by creating multiple directories/files and moving the card
back and forth to different reader.

IRQF_DISABLED is now pointless, remove it from request_irq?

drivers/mmc/host/Kconfig | 9 +
drivers/mmc/host/Makefile | 1 +
drivers/mmc/host/sdhci-moxart.c | 786 ++++++++++++++++++++++++++++++++++++++++
drivers/mmc/host/sdhci-moxart.h | 155 ++++++++
4 files changed, 951 insertions(+)
create mode 100644 drivers/mmc/host/sdhci-moxart.c
create mode 100644 drivers/mmc/host/sdhci-moxart.h

diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
index 1be2289..fb401c4 100644
--- a/drivers/mmc/host/Kconfig
+++ b/drivers/mmc/host/Kconfig
@@ -260,6 +260,15 @@ config MMC_SDHCI_BCM2835

If unsure, say N.

+config MMC_SDHCI_MOXART
+ tristate "MOXART SD Host Controller Interface support"
+ depends on ARCH_MOXART && MMC
+ help
+ This selects the MOXART SD Host Controller Interface.
+ MOXA provides one multi-functional card reader which can
+ be found on some embedded hardware such as UC-7112-LX.
+ If you have a controller with this interface, say Y here.
+
config MMC_OMAP
tristate "TI OMAP Multimedia Card Interface support"
depends on ARCH_OMAP
diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
index 67718c1..274199a 100644
--- a/drivers/mmc/host/Makefile
+++ b/drivers/mmc/host/Makefile
@@ -62,6 +62,7 @@ obj-$(CONFIG_MMC_SDHCI_TEGRA) += sdhci-tegra.o
obj-$(CONFIG_MMC_SDHCI_OF_ESDHC) += sdhci-of-esdhc.o
obj-$(CONFIG_MMC_SDHCI_OF_HLWD) += sdhci-of-hlwd.o
obj-$(CONFIG_MMC_SDHCI_BCM2835) += sdhci-bcm2835.o
+obj-$(CONFIG_MMC_SDHCI_MOXART) += sdhci-moxart.o

ifeq ($(CONFIG_CB710_DEBUG),y)
CFLAGS-cb710-mmc += -DDEBUG
diff --git a/drivers/mmc/host/sdhci-moxart.c b/drivers/mmc/host/sdhci-moxart.c
new file mode 100644
index 0000000..f5aaea6
--- /dev/null
+++ b/drivers/mmc/host/sdhci-moxart.c
@@ -0,0 +1,786 @@
+/*
+ * MOXA ART MMC host driver.
+ *
+ * Copyright (C) 2013 Jonas Jensen
+ *
+ * Jonas Jensen <[email protected]>
+ *
+ * Based on code from
+ * Moxa Technology Co., Ltd. <http://www.moxa.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/version.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/ioport.h>
+#include <linux/platform_device.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/blkdev.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
+#include <linux/mmc/host.h>
+#include <linux/mmc/sd.h>
+#include <linux/mmc/mmc.h>
+#include <linux/sched.h>
+#include <linux/io.h>
+#include <linux/gpio.h>
+#include <linux/sizes.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/clk.h>
+
+#include <asm/dma.h>
+#include <asm/irq.h>
+
+#include "sdhci-moxart.h"
+
+#define DMA_FIFO_LEN_FORCE 0
+#define APB_DMA_SD_REQ_NO 5
+#define MIN_POWER (MMC_VDD_360 - MSD_SD_POWER_MASK)
+
+static inline void moxart_init_sg(struct moxart_host *host,
+ struct mmc_data *data)
+{
+ host->cur_sg = data->sg;
+ host->num_sg = data->sg_len;
+ host->remain = host->cur_sg->length;
+
+ if (host->remain > host->size)
+ host->remain = host->size;
+
+ data->error = MMC_ERR_NONE;
+}
+
+static inline int moxart_next_sg(struct moxart_host *host)
+{
+ int remain;
+ struct mmc_data *data = host->mrq->cmd->data;
+
+ host->cur_sg++;
+ host->num_sg--;
+
+ if (host->num_sg > 0) {
+ host->remain = host->cur_sg->length;
+ remain = host->size - data->bytes_xfered;
+ if (remain > 0 && remain < host->remain)
+ host->remain = remain;
+ }
+
+ return host->num_sg;
+}
+
+static void moxart_send_command(struct moxart_host *host,
+ struct mmc_command *cmd)
+{
+ unsigned int status, cmdctrl;
+ int retry = 0;
+
+ dev_dbg(mmc_dev(host->mmc), "%s: cmd->opcode=%d\n",
+ __func__, cmd->opcode);
+
+ cmd->error = MMC_ERR_TIMEOUT;
+
+ writel(MSD_RSP_TIMEOUT | MSD_RSP_CRC_OK |
+ MSD_RSP_CRC_FAIL | MSD_CMD_SENT, &host->reg->clear);
+ writel(cmd->arg, &host->reg->argument);
+
+ cmdctrl = cmd->opcode & MSD_CMD_IDX_MASK;
+ if (cmdctrl == SD_APP_SET_BUS_WIDTH || cmdctrl == SD_APP_OP_COND ||
+ cmdctrl == SD_APP_SEND_SCR || cmdctrl == SD_APP_SD_STATUS ||
+ cmdctrl == SD_APP_SEND_NUM_WR_BLKS)
+ cmdctrl |= MSD_APP_CMD;
+
+ if (cmd->flags & MMC_RSP_136)
+ cmdctrl |= (MSD_LONG_RSP | MSD_NEED_RSP);
+ else
+ cmdctrl |= MSD_NEED_RSP;
+
+ writel(cmdctrl | MSD_CMD_EN, &host->reg->command);
+
+ while (retry++ < MSD_RETRY_COUNT) {
+ udelay(10);
+ status = readl(&host->reg->status);
+ if (status & MSD_CARD_DETECT) {
+ dev_dbg(mmc_dev(host->mmc), "%s: MSD_CARD_DETECT\n",
+ __func__);
+ cmd->error = MMC_ERR_TIMEOUT;
+ break;
+ }
+ if (cmdctrl & MSD_NEED_RSP) {
+ dev_dbg(mmc_dev(host->mmc), "%s: MSD_NEED_RSP\n",
+ __func__);
+ if (status & MSD_RSP_TIMEOUT) {
+ dev_dbg(mmc_dev(host->mmc), "%s: MSD_RSP_TIMEOUT\n",
+ __func__);
+ writel(MSD_RSP_TIMEOUT, &host->reg->clear);
+ cmd->error = MMC_ERR_TIMEOUT;
+ break;
+ }
+ if ((cmd->flags & MMC_RSP_CRC) &&
+ (status & MSD_RSP_CRC_FAIL)) {
+ dev_dbg(mmc_dev(host->mmc), "%s: MSD_RSP_CRC_FAIL\n",
+ __func__);
+ writel(MSD_RSP_CRC_FAIL, &host->reg->clear);
+ cmd->error = MMC_ERR_BADCRC;
+ break;
+ }
+ if (status & MSD_RSP_CRC_OK) {
+ dev_dbg(mmc_dev(host->mmc), "%s: MSD_RSP_CRC_OK\n",
+ __func__);
+ writel(MSD_RSP_CRC_OK, &host->reg->clear);
+
+ if (cmd->flags & MMC_RSP_136) {
+ cmd->resp[3] =
+ readl(&host->reg->response0);
+ cmd->resp[2] =
+ readl(&host->reg->response1);
+ cmd->resp[1] =
+ readl(&host->reg->response2);
+ cmd->resp[0] =
+ readl(&host->reg->response3);
+ } else {
+ cmd->resp[0] =
+ readl(&host->reg->response0);
+ }
+
+ cmd->error = MMC_ERR_NONE;
+ break;
+ }
+ } else {
+ dev_dbg(mmc_dev(host->mmc), "%s: !(cmdctrl & MSD_NEED_RSP)\n",
+ __func__);
+ if (status & MSD_CMD_SENT) {
+ writel(MSD_CMD_SENT, &host->reg->clear);
+ cmd->error = MMC_ERR_NONE;
+ break;
+ }
+ }
+ }
+
+ if (retry >= (MSD_RETRY_COUNT - 1)) {
+ /*
+ * this seems to happen a lot on or after CMD25
+ * (MMC_WRITE_MULTIPLE_BLOCK) with more than 4 blocks
+ * (>4096), possibly because the transfer is too big
+ * or takes too long to complete.
+ * when this happens the controller is usually rendered
+ * unresponsive and can only be recovered with reboot.
+ */
+ dev_dbg(mmc_dev(host->mmc), "%s: WARNING! no valid status found!\n",
+ __func__);
+ }
+}
+
+static void moxart_dma_complete(void *param)
+{
+ struct moxart_host *host = param;
+
+ dev_dbg(mmc_dev(host->mmc), "%s: host=%p\n", __func__, host);
+ complete(&host->dma_complete);
+}
+
+static void moxart_transfer_dma(struct mmc_data *data, struct moxart_host *host)
+{
+ unsigned int len, direction_dev;
+ struct dma_async_tx_descriptor *desc = NULL;
+
+ if (host->size == data->bytes_xfered)
+ return;
+
+ direction_dev = (data->flags & MMC_DATA_WRITE) ?
+ DMA_MEM_TO_DEV : DMA_DEV_TO_MEM;
+
+ /*
+ * because dma_map_sg takes both sg and sg_len as arguments
+ * (and maps the entire list of buffers) data->sg does not
+ * have to be incremented between calls (as is required
+ * in moxart_transfer_pio)
+ */
+ len = dma_map_sg(host->dma_chan_cur->device->dev, data->sg,
+ data->sg_len, host->dma_direction);
+
+ if (len > 0) {
+ /* host->dma_active = true;*/
+ desc = dmaengine_prep_slave_sg(host->dma_chan_cur, data->sg,
+ len, direction_dev,
+ DMA_PREP_INTERRUPT |
+ DMA_CTRL_ACK);
+ } else {
+ pr_err("%s: dma_map_sg returned zero length\n",
+ __func__);
+ }
+
+ if (desc) {
+ desc->callback = moxart_dma_complete;
+ desc->callback_param = host;
+ dmaengine_submit(desc);
+ dma_async_issue_pending(host->dma_chan_cur);
+ }
+
+ data->bytes_xfered += host->remain;
+}
+
+/* when DMA is available this is used only for SD_APP_SEND_SCR */
+static void moxart_transfer_pio(struct moxart_host *host)
+{
+ unsigned char *buffer;
+ unsigned int wcnt, i;
+ struct mmc_data *data = host->mrq->cmd->data;
+
+ if (host->size == data->bytes_xfered)
+ goto transfer_complete;
+
+ buffer = sg_virt(host->cur_sg);
+ wcnt = host->remain >> 2;
+
+ if (data->flags & MMC_DATA_WRITE) {
+ for (i = 0; i < wcnt; i++, buffer += 4) {
+ writel(*(unsigned int *)buffer,
+ &host->reg->data_window);
+ udelay(10);
+ }
+ } else {
+ for (i = 0; i < wcnt; i++, buffer += 4) {
+ /* byte order reversed only when reading SCR */
+ if (data->mrq->cmd->opcode == SD_APP_SEND_SCR) {
+ *(unsigned int *)buffer = ioread32be(
+ &host->reg->data_window);
+ } else {
+ *(unsigned int *)buffer =
+ readl(&host->reg->data_window);
+ }
+ udelay(10);
+ }
+ }
+ wcnt <<= 2;
+ host->remain -= wcnt;
+ data->bytes_xfered += wcnt;
+
+ if (host->size != data->bytes_xfered) {
+ moxart_next_sg(host);
+ /*
+ * used to goto "transfer_start" label here,
+ * there is no need, this function will be
+ * called again from interrupt.
+ *
+ * compare with DMA where sg increment is
+ * redundant thanks to dma_map_sg
+ */
+ } else {
+ complete(&host->pio_complete);
+ }
+
+transfer_complete:
+ dev_dbg(mmc_dev(host->mmc), "%s: host->size=%d host->remain=%u\n",
+ __func__, host->size, host->remain);
+}
+
+static void moxart_prepare_data(struct moxart_host *host)
+{
+ struct mmc_data *data = host->mrq->cmd->data;
+ unsigned int timeout, datactrl;
+ int blksz_bits;
+
+ dev_dbg(mmc_dev(host->mmc), "%s\n", __func__);
+
+ if (!data)
+ return;
+
+ host->size = data->blocks * data->blksz;
+ blksz_bits = ffs(data->blksz) - 1;
+ BUG_ON(1 << blksz_bits != data->blksz);
+
+ moxart_init_sg(host, data);
+
+ timeout = (host->mmc->f_max / 1000) * (data->timeout_ns / 1000);
+ timeout *= 2;
+
+ datactrl = (blksz_bits & MSD_BLK_SIZE_MASK) | MSD_DATA_EN;
+
+ if (data->flags & MMC_DATA_WRITE)
+ datactrl |= MSD_DATA_WRITE;
+
+ if (((host->size > MSD_FIFO_LENB) || DMA_FIFO_LEN_FORCE)
+ && host->have_dma) {
+ datactrl |= MSD_DMA_EN;
+ }
+
+ dev_dbg(mmc_dev(host->mmc), "%s: blocks=%d blksz=%d datactrl=0x%08x\n",
+ __func__, data->blocks, data->blksz, datactrl);
+ dev_dbg(mmc_dev(host->mmc), "%s: timeout=%u timeout_ns=%u\n",
+ __func__, timeout, data->timeout_ns);
+
+ writel(timeout, &host->reg->data_timer);
+ writel(host->size, &host->reg->data_length);
+ writel(datactrl, &host->reg->data_control);
+}
+
+static void moxart_transfer_check(struct mmc_data *data,
+ struct moxart_host *host)
+{
+ unsigned int status, count = 0;
+
+ dev_dbg(mmc_dev(host->mmc), "%s\n", __func__);
+
+ while (1) {
+ udelay(10);
+ status = readl(&host->reg->status);
+ if (status & (MSD_DATA_CRC_OK | MSD_DATA_CRC_FAIL
+ | MSD_DATA_END) || count > 10)
+ break;
+ dev_dbg(mmc_dev(host->mmc), "%s: waiting for status=%08x ..\n",
+ __func__, status);
+ count++;
+ }
+ if (status & MSD_DATA_CRC_OK) {
+ dev_dbg(mmc_dev(host->mmc), "%s: MSD_DATA_CRC_OK\n", __func__);
+ writel(MSD_DATA_CRC_OK, &host->reg->clear);
+ }
+ if (status & MSD_DATA_CRC_FAIL) {
+ dev_dbg(mmc_dev(host->mmc), "%s: MSD_DATA_CRC_FAIL\n",
+ __func__);
+ writel(MSD_DATA_CRC_FAIL, &host->reg->clear);
+ data->error = MMC_ERR_TIMEOUT;
+ }
+ if (status & MSD_DATA_END) {
+ dev_dbg(mmc_dev(host->mmc), "%s: MSD_DATA_END\n",
+ __func__);
+ writel(MSD_DATA_END, &host->reg->clear);
+ }
+ if (status & MSD_DATA_TIMEOUT) {
+ dev_dbg(mmc_dev(host->mmc), "%s: MSD_DATA_TIMEOUT\n",
+ __func__);
+ writel(MSD_DATA_TIMEOUT, &host->reg->clear);
+ }
+}
+
+static void moxart_card_change(struct moxart_host *host)
+{
+ int delay;
+ unsigned long flags;
+
+ spin_lock_irqsave(&host->lock, flags);
+
+ if (readl(&host->reg->status) & MSD_CARD_DETECT) {
+ dev_dbg(mmc_dev(host->mmc), "%s: card removed\n", __func__);
+ if (host->have_dma && host->size > MSD_FIFO_LENB) {
+ dev_dbg(mmc_dev(host->mmc), "%s: call dmaengine_terminate_all\n",
+ __func__);
+ dmaengine_terminate_all(host->dma_chan_rx);
+ dmaengine_terminate_all(host->dma_chan_tx);
+ }
+ host->removed = true;
+ delay = 0;
+ } else {
+ dev_dbg(mmc_dev(host->mmc), "%s: card inserted\n", __func__);
+ host->removed = false;
+ delay = 500;
+ }
+
+ /*
+ * clearing FIFO interrupts here does not stop a follow up
+ * MSD_FIFO_*RUN after MSD_CARD_CHANGE. instead, check
+ * host->mrq != NULL in moxart_irq to avoid unnecessary calls
+ * to moxart_transfer_pio
+ * if this happens during transfer the mmc_request in
+ * moxart_request should still be valid
+ * (which is why host->mrq can be set NULL here)
+ */
+ host->mrq = NULL;
+ writel(MSD_CARD_CHANGE | MSD_FIFO_ORUN | MSD_FIFO_URUN,
+ &host->reg->clear);
+ writel(MSD_CARD_CHANGE, &host->reg->interrupt_mask);
+
+ spin_unlock_irqrestore(&host->lock, flags);
+ dev_dbg(mmc_dev(host->mmc), "%s: call mmc_detect_change\n", __func__);
+ mmc_detect_change(host->mmc, msecs_to_jiffies(delay));
+}
+
+static void moxart_request(struct mmc_host *mmc, struct mmc_request *mrq)
+{
+ struct moxart_host *host = mmc_priv(mmc);
+ unsigned long dma_time, pio_time, flags;
+ unsigned int status;
+
+ dev_dbg(mmc_dev(host->mmc), "%s\n", __func__);
+
+ spin_lock_irqsave(&host->lock, flags);
+
+ init_completion(&host->dma_complete);
+ init_completion(&host->pio_complete);
+
+ host->mrq = mrq;
+
+ if (readl(&host->reg->status) & MSD_CARD_DETECT) {
+ mrq->cmd->error = MMC_ERR_TIMEOUT;
+ goto request_done;
+ }
+
+ moxart_prepare_data(host);
+ moxart_send_command(host, host->mrq->cmd);
+
+ if (mrq->cmd->data) {
+ /* only use DMA/PIO (and wait) when there is data */
+ if (((host->size > MSD_FIFO_LENB) || DMA_FIFO_LEN_FORCE)
+ && host->have_dma) {
+
+ writel(MSD_CARD_CHANGE, &host->reg->interrupt_mask);
+
+ spin_unlock_irqrestore(&host->lock, flags);
+
+ host->dma_direction = (mrq->cmd->data->flags
+ & MMC_DATA_WRITE) ?
+ DMA_TO_DEVICE : DMA_FROM_DEVICE;
+ host->dma_chan_cur = (mrq->cmd->data->flags
+ & MMC_DATA_WRITE) ?
+ host->dma_chan_tx :
+ host->dma_chan_rx;
+ moxart_transfer_dma(mrq->cmd->data, host);
+
+ dma_time = wait_for_completion_interruptible_timeout(
+ &host->dma_complete, host->timeout);
+ dev_dbg(mmc_dev(host->mmc), "%s: dma_time=%lu (DMA wait time)\n",
+ __func__, dma_time);
+
+ dma_unmap_sg(host->dma_chan_cur->device->dev,
+ mrq->cmd->data->sg, mrq->cmd->data->sg_len,
+ host->dma_direction);
+
+ spin_lock_irqsave(&host->lock, flags);
+ } else {
+
+ writel(MSD_FIFO_URUN | MSD_FIFO_ORUN | MSD_CARD_CHANGE,
+ &host->reg->interrupt_mask);
+
+ status = readl(&host->reg->status);
+ dev_dbg(mmc_dev(host->mmc), "%s: status=%08x\n",
+ __func__, status);
+
+ spin_unlock_irqrestore(&host->lock, flags);
+
+ /* PIO transfer started from interrupt */
+ pio_time = wait_for_completion_interruptible_timeout(
+ &host->pio_complete, host->timeout);
+ dev_dbg(mmc_dev(host->mmc), "%s: pio_time=%lu (PIO wait time)\n",
+ __func__, pio_time);
+
+ spin_lock_irqsave(&host->lock, flags);
+ }
+
+ /* removed during transfer? (interrupts were just enabled..) */
+ if (host->removed) {
+ dev_dbg(mmc_dev(host->mmc), "%s: host removed during transfer!\n",
+ __func__);
+ mrq->cmd->error = MMC_ERR_TIMEOUT;
+ }
+
+ moxart_transfer_check(mrq->cmd->data, host);
+
+ if (mrq->cmd->data->stop)
+ moxart_send_command(host, mrq->cmd->data->stop);
+ }
+
+request_done:
+ spin_unlock_irqrestore(&host->lock, flags);
+ mmc_request_done(host->mmc, mrq);
+}
+
+static irqreturn_t moxart_irq(int irq, void *devid)
+{
+ struct moxart_host *host = (struct moxart_host *)devid;
+ unsigned int status;
+ unsigned long flags;
+
+ status = readl(&host->reg->status);
+
+ dev_dbg(mmc_dev(host->mmc), "%s: host=%p status=%08x\n",
+ __func__, host, status);
+
+ if (status & MSD_CARD_CHANGE) {
+ dev_dbg(mmc_dev(host->mmc), "%s: call moxart_card_change\n",
+ __func__);
+ moxart_card_change(host);
+ }
+ if (status & (MSD_FIFO_ORUN | MSD_FIFO_URUN) && host->mrq) {
+ writel(status & (MSD_FIFO_ORUN | MSD_FIFO_URUN),
+ &host->reg->clear);
+ dev_dbg(mmc_dev(host->mmc), "%s: call moxart_transfer_pio\n",
+ __func__);
+ spin_lock_irqsave(&host->lock, flags);
+ moxart_transfer_pio(host);
+ spin_unlock_irqrestore(&host->lock, flags);
+ }
+
+ return IRQ_HANDLED;
+}
+
+static void moxart_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
+{
+ struct moxart_host *host = mmc_priv(mmc);
+ unsigned long flags;
+ unsigned short power;
+ int div;
+
+ spin_lock_irqsave(&host->lock, flags);
+ if (ios->clock) {
+ div = (host->sysclk / (host->mmc->f_max * 2)) - 1;
+
+ if (div > MSD_CLK_DIV_MASK)
+ div = MSD_CLK_DIV_MASK;
+ else if (div < 0)
+ div = 0;
+
+ div |= MSD_CLK_SD;
+ writel(div, &host->reg->clock_control);
+ } else if (!(readl(&host->reg->clock_control) & MSD_CLK_DIS)) {
+ writel(readl(&host->reg->clock_control) | MSD_CLK_DIS,
+ &host->reg->clock_control);
+ }
+
+ if (ios->power_mode == MMC_POWER_OFF) {
+ writel(readl(&host->reg->power_control) & ~MSD_SD_POWER_ON,
+ &host->reg->power_control);
+ } else {
+ if (ios->vdd < MIN_POWER)
+ power = 0;
+ else
+ power = ios->vdd - MIN_POWER;
+
+ writel(MSD_SD_POWER_ON | (unsigned int) power,
+ &host->reg->power_control);
+ }
+
+ if (ios->bus_width == MMC_BUS_WIDTH_1)
+ writel(MSD_SINGLE_BUS, &host->reg->bus_width);
+ else
+ writel(MSD_WIDE_BUS, &host->reg->bus_width);
+
+ spin_unlock_irqrestore(&host->lock, flags);
+}
+
+
+static int moxart_get_ro(struct mmc_host *mmc)
+{
+ int ret;
+ struct moxart_host *host = mmc_priv(mmc);
+
+ (readl(&host->reg->status) & MSD_WRITE_PROT) ? (ret = 1) : (ret = 0);
+ return ret;
+}
+
+static struct mmc_host_ops moxart_ops = {
+ .request = moxart_request,
+ .set_ios = moxart_set_ios,
+ .get_ro = moxart_get_ro,
+};
+
+static int moxart_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct device_node *node = dev->of_node;
+ struct resource res_mmc;
+ struct mmc_host *mmc;
+ struct moxart_host *host = NULL;
+ void __iomem *reg_mmc;
+ dma_cap_mask_t mask;
+ int ret;
+ struct dma_slave_config cfg;
+ unsigned int irq;
+ struct clk *clk;
+ unsigned int dma_chan_rx_req = 1;
+ unsigned int dma_chan_tx_req = 0;
+
+ mmc = mmc_alloc_host(sizeof(struct moxart_host), dev);
+ if (!mmc) {
+ dev_err(dev, "%s: mmc_alloc_host failed\n", __func__);
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ ret = of_address_to_resource(node, 0, &res_mmc);
+ if (ret) {
+ dev_err(dev, "%s: could not get MMC base resource\n", __func__);
+ goto out;
+ }
+
+ irq = irq_of_parse_and_map(node, 0);
+
+ reg_mmc = devm_ioremap_resource(dev, &res_mmc);
+ if (IS_ERR(reg_mmc)) {
+ dev_err(dev, "%s: devm_ioremap_resource res_mmc failed\n",
+ __func__);
+ return PTR_ERR(reg_mmc);
+ }
+
+ mmc->ops = &moxart_ops;
+
+ /*
+ * hardware does not support MMC_CAP_SD_HIGHSPEED
+ * CMD6 will timeout and make things not work
+ */
+ mmc->caps = MMC_CAP_4_BIT_DATA;
+
+ mmc->f_min = 400000;
+ mmc->f_max = 25000000;
+ mmc->ocr_avail = 0xffff00; /* support 2.0v - 3.6v power */
+ mmc->max_segs = 32;
+ mmc->max_blk_size = 512;
+ mmc->max_blk_count = mmc->max_req_size / mmc->max_blk_size;
+ mmc->max_seg_size = mmc->max_req_size;
+
+ host = mmc_priv(mmc);
+ host->mmc = mmc;
+ host->reg = (struct moxart_reg *)reg_mmc;
+ host->reg_phys = res_mmc.start;
+ host->timeout = msecs_to_jiffies(1000);
+
+ dma_cap_zero(mask);
+ dma_cap_set(DMA_SLAVE, mask);
+
+ clk = of_clk_get(node, 0);
+ if (IS_ERR(clk)) {
+ dev_err(dev, "%s: of_clk_get failed\n", __func__);
+ return PTR_ERR(clk);
+ }
+ host->sysclk = clk_get_rate(clk);
+
+ spin_lock_init(&host->lock);
+
+ /* disable all interrupt */
+ writel(0, &host->reg->interrupt_mask);
+
+ /* reset chip */
+ writel(MSD_SDC_RST, &host->reg->command);
+
+ /* wait for reset finished */
+ while (readl(&host->reg->command) & MSD_SDC_RST)
+ udelay(10);
+
+ host->dma_chan_tx = dma_request_channel(mask, moxart_filter_fn,
+ (void *)&dma_chan_tx_req);
+ host->dma_chan_rx = dma_request_channel(mask, moxart_filter_fn,
+ (void *)&dma_chan_rx_req);
+ dev_dbg(dev, "%s: using 2 DMA channels rx=%p tx=%p\n",
+ __func__, host->dma_chan_rx, host->dma_chan_tx);
+
+ if (!host->dma_chan_rx || !host->dma_chan_tx) {
+ host->have_dma = false;
+ mmc->max_blk_count = 1;
+ } else {
+ cfg.slave_id = APB_DMA_SD_REQ_NO;
+ cfg.direction = DMA_MEM_TO_DEV;
+ cfg.src_addr = 0;
+ cfg.dst_addr = (unsigned int)host->reg_phys + MSD_DATA_WIN_REG;
+ cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+ dmaengine_slave_config(host->dma_chan_tx, &cfg);
+
+ cfg.slave_id = APB_DMA_SD_REQ_NO;
+ cfg.direction = DMA_DEV_TO_MEM;
+ cfg.src_addr = (unsigned int)host->reg_phys + MSD_DATA_WIN_REG;
+ cfg.dst_addr = 0;
+ cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+ dmaengine_slave_config(host->dma_chan_rx, &cfg);
+
+ host->have_dma = true;
+
+ /*
+ * there seems to be a max size on transfers so
+ * set max_blk_count low for both DMA and PIO
+ *
+ * sending large chunks result either in timeout
+ * or render the MMC controller unresponsive
+ * (status register 0 on consecutive read retries,
+ * also see comments in moxart_send_command)
+ *
+ * obviously, DMA is quicker and can handle
+ * larger chunks but setting it higher than 16
+ * can still bug the controller
+ */
+ mmc->max_blk_count = 16;
+ }
+
+ ret = request_irq(irq, moxart_irq,
+ IRQF_DISABLED, "moxart-mmc", host);
+
+ if (ret)
+ goto out;
+
+ dev_set_drvdata(dev, mmc);
+ mmc_add_host(mmc);
+
+ dev_dbg(dev, "%s: IRQ=%d\n", __func__, irq);
+
+ return 0;
+
+out:
+ if (mmc)
+ mmc_free_host(mmc);
+ return ret;
+}
+
+static void moxart_release_dma(struct moxart_host *host)
+{
+ if (host->dma_chan_tx) {
+ struct dma_chan *chan = host->dma_chan_tx;
+ host->dma_chan_tx = NULL;
+ dma_release_channel(chan);
+ }
+ if (host->dma_chan_rx) {
+ struct dma_chan *chan = host->dma_chan_rx;
+ host->dma_chan_rx = NULL;
+ dma_release_channel(chan);
+ }
+}
+
+static int moxart_remove(struct platform_device *pdev)
+{
+ struct mmc_host *mmc = dev_get_drvdata(&pdev->dev);
+ struct moxart_host *host = mmc_priv(mmc);
+ struct resource *res_irq;
+
+ res_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 2);
+
+ dev_set_drvdata(&pdev->dev, NULL);
+
+ if (mmc) {
+ moxart_release_dma(host);
+ mmc_remove_host(mmc);
+
+ writel(0, &host->reg->interrupt_mask);
+ writel(0, &host->reg->power_control);
+ writel(readl(&host->reg->clock_control) | MSD_CLK_DIS,
+ &host->reg->clock_control);
+
+ free_irq(res_irq->start, host);
+
+ mmc_free_host(mmc);
+ }
+ return 0;
+}
+
+static const struct of_device_id moxart_mmc_match[] = {
+ { .compatible = "moxa,moxart-mmc" },
+ { }
+};
+
+static struct platform_driver moxart_mmc_driver = {
+ .probe = moxart_probe,
+ .remove = moxart_remove,
+ .driver = {
+ .name = "sdhci-moxart",
+ .owner = THIS_MODULE,
+ .of_match_table = moxart_mmc_match,
+ },
+};
+module_platform_driver(moxart_mmc_driver);
+
+MODULE_ALIAS("platform:sdhci-moxart");
+MODULE_DESCRIPTION("MOXART SDHCI driver");
+MODULE_VERSION("1.0");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Jonas Jensen <[email protected]>");
diff --git a/drivers/mmc/host/sdhci-moxart.h b/drivers/mmc/host/sdhci-moxart.h
new file mode 100644
index 0000000..f60bed1
--- /dev/null
+++ b/drivers/mmc/host/sdhci-moxart.h
@@ -0,0 +1,155 @@
+/*
+ * MOXA ART MMC host driver.
+ *
+ * Copyright (C) 2013 Jonas Jensen
+ *
+ * Jonas Jensen <[email protected]>
+ *
+ * Based on code from
+ * Moxa Technology Co., Ltd. <http://www.moxa.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#ifndef _SDHCI_MOXART_H
+#define _SDHCI_MOXART_H
+
+extern bool moxart_filter_fn(struct dma_chan *chan, void *param);
+
+#define MSD_CMD_REG 0
+#define MSD_ARG_REG 4
+#define MSD_RESP0_REG 8
+#define MSD_RESP1_REG 0x0c
+#define MSD_RESP2_REG 0x10
+#define MSD_RESP3_REG 0x14
+#define MSD_RESP_CMD_REG 0x18
+#define MSD_DATA_CTRL_REG 0x1c
+#define MSD_DATA_TIMER_REG 0x20
+#define MSD_DATA_LEN_REG 0x24
+#define MSD_STATUS_REG 0x28
+#define MSD_CLEAR_REG 0x2c
+#define MSD_INT_MASK_REG 0x30
+#define MSD_POWER_CTRL_REG 0x34
+#define MSD_CLOCK_CTRL_REG 0x38
+#define MSD_BUS_WIDTH_REG 0x3c
+#define MSD_DATA_WIN_REG 0x40
+#define MSD_FEATURE_REG 0x44
+#define MSD_REVISION_REG 0x48
+
+#define MMC_RSP_SHORT (1 << 0)
+#define MMC_RSP_LONG (2 << 0)
+#define MMC_RSP_MASK (3 << 0)
+#define MMC_ERR_NONE 0
+#define MMC_ERR_TIMEOUT 1
+#define MMC_MODE_MMC 0
+#define MMC_MODE_SD 1
+#define MMC_ERR_BADCRC 2
+#define MMC_VDD_360 23
+
+#define MSD_RETRY_COUNT 10
+
+struct moxart_reg {
+
+#define MSD_SDC_RST (1<<10)
+#define MSD_CMD_EN (1<<9)
+#define MSD_APP_CMD (1<<8)
+#define MSD_LONG_RSP (1<<7)
+#define MSD_NEED_RSP (1<<6)
+#define MSD_CMD_IDX_MASK 0x3f
+ unsigned int command;
+
+ unsigned int argument;
+ unsigned int response0;
+ unsigned int response1;
+ unsigned int response2;
+ unsigned int response3;
+
+#define MSD_RSP_CMD_APP (1<<6)
+#define MSD_RSP_CMD_IDX_MASK 0x3f
+ unsigned int response_command;
+
+#define MSD_DATA_EN (1<<6)
+#define MSD_DMA_EN (1<<5)
+#define MSD_DATA_WRITE (1<<4)
+#define MSD_BLK_SIZE_MASK 0x0f
+ unsigned int data_control;
+
+ unsigned int data_timer;
+
+#define MSD_DATA_LEN_MASK 0xffffff
+ unsigned int data_length;
+
+#define MSD_WRITE_PROT (1<<12)
+#define MSD_CARD_DETECT (1<<11)
+/* 1-10 below can be sent to interrupt or clear register */
+#define MSD_CARD_CHANGE (1<<10)
+#define MSD_FIFO_ORUN (1<<9)
+#define MSD_FIFO_URUN (1<<8)
+#define MSD_DATA_END (1<<7)
+#define MSD_CMD_SENT (1<<6)
+#define MSD_DATA_CRC_OK (1<<5)
+#define MSD_RSP_CRC_OK (1<<4)
+#define MSD_DATA_TIMEOUT (1<<3)
+#define MSD_RSP_TIMEOUT (1<<2)
+#define MSD_DATA_CRC_FAIL (1<<1)
+#define MSD_RSP_CRC_FAIL (1<<0)
+ unsigned int status;
+
+ unsigned int clear;
+ unsigned int interrupt_mask;
+
+#define MSD_SD_POWER_ON (1<<4)
+#define MSD_SD_POWER_MASK 0x0f
+ unsigned int power_control;
+
+#define MSD_CLK_DIS (1<<8)
+#define MSD_CLK_SD (1<<7)
+#define MSD_CLK_DIV_MASK 0x7f
+ unsigned int clock_control;
+
+#define MSD_WIDE_BUS_SUPPORT (1<<3)
+#define MSD_WIDE_BUS (1<<2) /* bus width is 4 bytes */
+#define MSD_SINGLE_BUS (1<<0) /* bus width is 1 byte */
+ unsigned int bus_width;
+
+ unsigned int data_window;
+
+#define MSD_CPRM_FUNCTION (1<<8)
+ unsigned int feature;
+
+ unsigned int revision;
+};
+
+struct moxart_host {
+ spinlock_t lock;
+ struct moxart_reg *reg;
+ phys_addr_t reg_phys;
+
+ struct dma_chan *dma_chan_rx;
+ struct dma_chan *dma_chan_tx;
+ struct dma_chan *dma_chan_cur;
+ unsigned int dma_direction;
+ bool have_dma;
+ struct completion dma_complete;
+ struct completion pio_complete;
+
+ struct mmc_host *mmc;
+ struct mmc_request *mrq;
+
+ struct scatterlist *cur_sg;
+ unsigned int num_sg;
+ unsigned int remain;
+ int size;
+
+ unsigned int wait_for;
+ unsigned int timeout;
+ long sysclk;
+ bool removed;
+};
+
+#define MSD_FIFO_LENW 4 /* 4 words, total 4 * 4 = 16 bytes */
+#define MSD_FIFO_LENB 16 /* 16 bytes */
+
+#endif /* _SDHCI_MOXART_H */
--
1.8.2.1

2013-07-17 12:51:58

by Jonas Jensen

Subject: [PATCH v2] mmc: sdhci-moxart: Add MOXA ART SDHCI driver

Add SDHCI driver for MOXA ART SoCs.

Signed-off-by: Jonas Jensen <[email protected]>
---

Notes:
Changes since v1:

1. remove IRQF_DISABLED
2. use devm_request_irq, remove free_irq
3. remove unnecessary dev_set_drvdata in moxart_remove
4. add devicetree bindings document
5. use BIT macro in header file

Applies to next-20130716

.../devicetree/bindings/mmc/moxa,moxart-mmc.txt | 17 +
drivers/mmc/host/Kconfig | 9 +
drivers/mmc/host/Makefile | 1 +
drivers/mmc/host/sdhci-moxart.c | 780 +++++++++++++++++++++
drivers/mmc/host/sdhci-moxart.h | 155 ++++
5 files changed, 962 insertions(+)
create mode 100644 Documentation/devicetree/bindings/mmc/moxa,moxart-mmc.txt
create mode 100644 drivers/mmc/host/sdhci-moxart.c
create mode 100644 drivers/mmc/host/sdhci-moxart.h

diff --git a/Documentation/devicetree/bindings/mmc/moxa,moxart-mmc.txt b/Documentation/devicetree/bindings/mmc/moxa,moxart-mmc.txt
new file mode 100644
index 0000000..9ec8650
--- /dev/null
+++ b/Documentation/devicetree/bindings/mmc/moxa,moxart-mmc.txt
@@ -0,0 +1,17 @@
+MOXA ART SD Host Controller Interface
+
+Required properties:
+
+- compatible : Should be "moxa,moxart-mmc"
+- reg : Should contain registers location and length
+- interrupts : Should contain the interrupt number
+- clocks : Should contain phandle for APB clock "clkapb"
+
+Example:
+
+ mmc: mmc@98e00000 {
+ compatible = "moxa,moxart-mmc";
+ reg = <0x98e00000 0x5C>;
+ interrupts = <5 0>;
+ clocks = <&clkapb>;
+ };
diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
index 8a4c066..3c246390 100644
--- a/drivers/mmc/host/Kconfig
+++ b/drivers/mmc/host/Kconfig
@@ -271,6 +271,15 @@ config MMC_SDHCI_BCM2835

If unsure, say N.

+config MMC_SDHCI_MOXART
+ tristate "MOXART SD Host Controller Interface support"
+ depends on ARCH_MOXART && MMC
+ help
+ This selects the MOXART SD Host Controller Interface.
+ MOXA provides one multi-functional card reader which can
+ be found on some embedded hardware such as UC-7112-LX.
+ If you have a controller with this interface, say Y here.
+
config MMC_OMAP
tristate "TI OMAP Multimedia Card Interface support"
depends on ARCH_OMAP
diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
index d422e21..c91317f 100644
--- a/drivers/mmc/host/Makefile
+++ b/drivers/mmc/host/Makefile
@@ -63,6 +63,7 @@ obj-$(CONFIG_MMC_SDHCI_OF_ESDHC) += sdhci-of-esdhc.o
obj-$(CONFIG_MMC_SDHCI_OF_HLWD) += sdhci-of-hlwd.o
obj-$(CONFIG_MMC_SDHCI_BCM_KONA) += sdhci-bcm-kona.o
obj-$(CONFIG_MMC_SDHCI_BCM2835) += sdhci-bcm2835.o
+obj-$(CONFIG_MMC_SDHCI_MOXART) += sdhci-moxart.o

ifeq ($(CONFIG_CB710_DEBUG),y)
CFLAGS-cb710-mmc += -DDEBUG
diff --git a/drivers/mmc/host/sdhci-moxart.c b/drivers/mmc/host/sdhci-moxart.c
new file mode 100644
index 0000000..9d809b5
--- /dev/null
+++ b/drivers/mmc/host/sdhci-moxart.c
@@ -0,0 +1,780 @@
+/*
+ * MOXA ART MMC host driver.
+ *
+ * Copyright (C) 2013 Jonas Jensen
+ *
+ * Jonas Jensen <[email protected]>
+ *
+ * Based on code from
+ * Moxa Technology Co., Ltd. <http://www.moxa.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/version.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/ioport.h>
+#include <linux/platform_device.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/blkdev.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
+#include <linux/mmc/host.h>
+#include <linux/mmc/sd.h>
+#include <linux/mmc/mmc.h>
+#include <linux/sched.h>
+#include <linux/io.h>
+#include <linux/gpio.h>
+#include <linux/sizes.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/clk.h>
+
+#include <asm/dma.h>
+#include <asm/irq.h>
+
+#include "sdhci-moxart.h"
+
+#define DMA_FIFO_LEN_FORCE 0
+#define APB_DMA_SD_REQ_NO 5
+#define MIN_POWER (MMC_VDD_360 - MSD_SD_POWER_MASK)
+
+static inline void moxart_init_sg(struct moxart_host *host,
+ struct mmc_data *data)
+{
+ host->cur_sg = data->sg;
+ host->num_sg = data->sg_len;
+ host->remain = host->cur_sg->length;
+
+ if (host->remain > host->size)
+ host->remain = host->size;
+
+ data->error = MMC_ERR_NONE;
+}
+
+static inline int moxart_next_sg(struct moxart_host *host)
+{
+ int remain;
+ struct mmc_data *data = host->mrq->cmd->data;
+
+ host->cur_sg++;
+ host->num_sg--;
+
+ if (host->num_sg > 0) {
+ host->remain = host->cur_sg->length;
+ remain = host->size - data->bytes_xfered;
+ if (remain > 0 && remain < host->remain)
+ host->remain = remain;
+ }
+
+ return host->num_sg;
+}
+
+static void moxart_send_command(struct moxart_host *host,
+ struct mmc_command *cmd)
+{
+ unsigned int status, cmdctrl;
+ int retry = 0;
+
+ dev_dbg(mmc_dev(host->mmc), "%s: cmd->opcode=%d\n",
+ __func__, cmd->opcode);
+
+ cmd->error = MMC_ERR_TIMEOUT;
+
+ writel(MSD_RSP_TIMEOUT | MSD_RSP_CRC_OK |
+ MSD_RSP_CRC_FAIL | MSD_CMD_SENT, &host->reg->clear);
+ writel(cmd->arg, &host->reg->argument);
+
+ cmdctrl = cmd->opcode & MSD_CMD_IDX_MASK;
+ if (cmdctrl == SD_APP_SET_BUS_WIDTH || cmdctrl == SD_APP_OP_COND ||
+ cmdctrl == SD_APP_SEND_SCR || cmdctrl == SD_APP_SD_STATUS ||
+ cmdctrl == SD_APP_SEND_NUM_WR_BLKS)
+ cmdctrl |= MSD_APP_CMD;
+
+ if (cmd->flags & MMC_RSP_136)
+ cmdctrl |= (MSD_LONG_RSP | MSD_NEED_RSP);
+ else
+ cmdctrl |= MSD_NEED_RSP;
+
+ writel(cmdctrl | MSD_CMD_EN, &host->reg->command);
+
+ while (retry++ < MSD_RETRY_COUNT) {
+ udelay(10);
+ status = readl(&host->reg->status);
+ if (status & MSD_CARD_DETECT) {
+ dev_dbg(mmc_dev(host->mmc), "%s: MSD_CARD_DETECT\n",
+ __func__);
+ cmd->error = MMC_ERR_TIMEOUT;
+ break;
+ }
+ if (cmdctrl & MSD_NEED_RSP) {
+ dev_dbg(mmc_dev(host->mmc), "%s: MSD_NEED_RSP\n",
+ __func__);
+ if (status & MSD_RSP_TIMEOUT) {
+ dev_dbg(mmc_dev(host->mmc), "%s: MSD_RSP_TIMEOUT\n",
+ __func__);
+ writel(MSD_RSP_TIMEOUT, &host->reg->clear);
+ cmd->error = MMC_ERR_TIMEOUT;
+ break;
+ }
+ if ((cmd->flags & MMC_RSP_CRC) &&
+ (status & MSD_RSP_CRC_FAIL)) {
+ dev_dbg(mmc_dev(host->mmc), "%s: MSD_RSP_CRC_FAIL\n",
+ __func__);
+ writel(MSD_RSP_CRC_FAIL, &host->reg->clear);
+ cmd->error = MMC_ERR_BADCRC;
+ break;
+ }
+ if (status & MSD_RSP_CRC_OK) {
+ dev_dbg(mmc_dev(host->mmc), "%s: MSD_RSP_CRC_OK\n",
+ __func__);
+ writel(MSD_RSP_CRC_OK, &host->reg->clear);
+
+ if (cmd->flags & MMC_RSP_136) {
+ cmd->resp[3] =
+ readl(&host->reg->response0);
+ cmd->resp[2] =
+ readl(&host->reg->response1);
+ cmd->resp[1] =
+ readl(&host->reg->response2);
+ cmd->resp[0] =
+ readl(&host->reg->response3);
+ } else {
+ cmd->resp[0] =
+ readl(&host->reg->response0);
+ }
+
+ cmd->error = MMC_ERR_NONE;
+ break;
+ }
+ } else {
+ dev_dbg(mmc_dev(host->mmc), "%s: !(cmdctrl & MSD_NEED_RSP)\n",
+ __func__);
+ if (status & MSD_CMD_SENT) {
+ writel(MSD_CMD_SENT, &host->reg->clear);
+ cmd->error = MMC_ERR_NONE;
+ break;
+ }
+ }
+ }
+
+ if (retry >= (MSD_RETRY_COUNT - 1)) {
+ /*
+ * this seems to happen a lot on or after CMD25
+ * (MMC_WRITE_MULTIPLE_BLOCK) with more than 4 blocks
+ * (>4096), possibly because the transfer is too big
+ * or takes too long to complete.
+ * when this happens the controller is usually rendered
+ * unresponsive and can only be recovered with reboot.
+ */
+ dev_dbg(mmc_dev(host->mmc), "%s: WARNING! no valid status found!\n",
+ __func__);
+ }
+}
+
+static void moxart_dma_complete(void *param)
+{
+ struct moxart_host *host = param;
+
+ dev_dbg(mmc_dev(host->mmc), "%s: host=%p\n", __func__, host);
+ complete(&host->dma_complete);
+}
+
+static void moxart_transfer_dma(struct mmc_data *data, struct moxart_host *host)
+{
+ unsigned int len, direction_dev;
+ struct dma_async_tx_descriptor *desc = NULL;
+
+ if (host->size == data->bytes_xfered)
+ return;
+
+ direction_dev = (data->flags & MMC_DATA_WRITE) ?
+ DMA_MEM_TO_DEV : DMA_DEV_TO_MEM;
+
+ /*
+ * because dma_map_sg takes both sg and sg_len as arguments
+ * (and maps the entire list of buffers) data->sg does not
+ * have to be incremented between calls (as is required
+ * in moxart_transfer_pio)
+ */
+ len = dma_map_sg(host->dma_chan_cur->device->dev, data->sg,
+ data->sg_len, host->dma_direction);
+
+ if (len > 0) {
+ /* host->dma_active = true;*/
+ desc = dmaengine_prep_slave_sg(host->dma_chan_cur, data->sg,
+ len, direction_dev,
+ DMA_PREP_INTERRUPT |
+ DMA_CTRL_ACK);
+ } else {
+ pr_err("%s: dma_map_sg returned zero length\n",
+ __func__);
+ }
+
+ if (desc) {
+ desc->callback = moxart_dma_complete;
+ desc->callback_param = host;
+ dmaengine_submit(desc);
+ dma_async_issue_pending(host->dma_chan_cur);
+ }
+
+ data->bytes_xfered += host->remain;
+}
+
+/* when DMA is available this is used only for SD_APP_SEND_SCR */
+static void moxart_transfer_pio(struct moxart_host *host)
+{
+ unsigned char *buffer;
+ unsigned int wcnt, i;
+ struct mmc_data *data = host->mrq->cmd->data;
+
+ if (host->size == data->bytes_xfered)
+ goto transfer_complete;
+
+ buffer = sg_virt(host->cur_sg);
+ wcnt = host->remain >> 2;
+
+ if (data->flags & MMC_DATA_WRITE) {
+ for (i = 0; i < wcnt; i++, buffer += 4) {
+ writel(*(unsigned int *)buffer,
+ &host->reg->data_window);
+ udelay(10);
+ }
+ } else {
+ for (i = 0; i < wcnt; i++, buffer += 4) {
+ /* byte order reversed only when reading SCR */
+ if (data->mrq->cmd->opcode == SD_APP_SEND_SCR) {
+ *(unsigned int *)buffer = ioread32be(
+ &host->reg->data_window);
+ } else {
+ *(unsigned int *)buffer =
+ readl(&host->reg->data_window);
+ }
+ udelay(10);
+ }
+ }
+ wcnt <<= 2;
+ host->remain -= wcnt;
+ data->bytes_xfered += wcnt;
+
+ if (host->size != data->bytes_xfered) {
+ moxart_next_sg(host);
+ /*
+ * used to goto "transfer_start" label here,
+ * there is no need, this function will be
+ * called again from interrupt.
+ *
+ * compare with DMA where sg increment is
+ * redundant thanks to dma_map_sg
+ */
+ } else {
+ complete(&host->pio_complete);
+ }
+
+transfer_complete:
+ dev_dbg(mmc_dev(host->mmc), "%s: host->size=%d host->remain=%u\n",
+ __func__, host->size, host->remain);
+}
+
+static void moxart_prepare_data(struct moxart_host *host)
+{
+ struct mmc_data *data = host->mrq->cmd->data;
+ unsigned int timeout, datactrl;
+ int blksz_bits;
+
+ dev_dbg(mmc_dev(host->mmc), "%s\n", __func__);
+
+ if (!data)
+ return;
+
+ host->size = data->blocks * data->blksz;
+ blksz_bits = ffs(data->blksz) - 1;
+ BUG_ON(1 << blksz_bits != data->blksz);
+
+ moxart_init_sg(host, data);
+
+ timeout = (host->mmc->f_max / 1000) * (data->timeout_ns / 1000);
+ timeout *= 2;
+
+ datactrl = (blksz_bits & MSD_BLK_SIZE_MASK) | MSD_DATA_EN;
+
+ if (data->flags & MMC_DATA_WRITE)
+ datactrl |= MSD_DATA_WRITE;
+
+ if (((host->size > MSD_FIFO_LENB) || DMA_FIFO_LEN_FORCE)
+ && host->have_dma) {
+ datactrl |= MSD_DMA_EN;
+ }
+
+ dev_dbg(mmc_dev(host->mmc), "%s: blocks=%d blksz=%d datactrl=0x%08x\n",
+ __func__, data->blocks, data->blksz, datactrl);
+ dev_dbg(mmc_dev(host->mmc), "%s: timeout=%u timeout_ns=%u\n",
+ __func__, timeout, data->timeout_ns);
+
+ writel(timeout, &host->reg->data_timer);
+ writel(host->size, &host->reg->data_length);
+ writel(datactrl, &host->reg->data_control);
+}
+
+static void moxart_transfer_check(struct mmc_data *data,
+ struct moxart_host *host)
+{
+ unsigned int status, count = 0;
+
+ dev_dbg(mmc_dev(host->mmc), "%s\n", __func__);
+
+ while (1) {
+ udelay(10);
+ status = readl(&host->reg->status);
+ if (status & (MSD_DATA_CRC_OK | MSD_DATA_CRC_FAIL
+ | MSD_DATA_END) || count > 10)
+ break;
+ dev_dbg(mmc_dev(host->mmc), "%s: waiting for status=%08x ..\n",
+ __func__, status);
+ count++;
+ }
+ if (status & MSD_DATA_CRC_OK) {
+ dev_dbg(mmc_dev(host->mmc), "%s: MSD_DATA_CRC_OK\n", __func__);
+ writel(MSD_DATA_CRC_OK, &host->reg->clear);
+ }
+ if (status & MSD_DATA_CRC_FAIL) {
+ dev_dbg(mmc_dev(host->mmc), "%s: MSD_DATA_CRC_FAIL\n",
+ __func__);
+ writel(MSD_DATA_CRC_FAIL, &host->reg->clear);
+ data->error = MMC_ERR_TIMEOUT;
+ }
+ if (status & MSD_DATA_END) {
+ dev_dbg(mmc_dev(host->mmc), "%s: MSD_DATA_END\n",
+ __func__);
+ writel(MSD_DATA_END, &host->reg->clear);
+ }
+ if (status & MSD_DATA_TIMEOUT) {
+ dev_dbg(mmc_dev(host->mmc), "%s: MSD_DATA_TIMEOUT\n",
+ __func__);
+ writel(MSD_DATA_TIMEOUT, &host->reg->clear);
+ }
+}
+
+static void moxart_card_change(struct moxart_host *host)
+{
+ int delay;
+ unsigned long flags;
+
+ spin_lock_irqsave(&host->lock, flags);
+
+ if (readl(&host->reg->status) & MSD_CARD_DETECT) {
+ dev_dbg(mmc_dev(host->mmc), "%s: card removed\n", __func__);
+ if (host->have_dma && host->size > MSD_FIFO_LENB) {
+ dev_dbg(mmc_dev(host->mmc), "%s: call dmaengine_terminate_all\n",
+ __func__);
+ dmaengine_terminate_all(host->dma_chan_rx);
+ dmaengine_terminate_all(host->dma_chan_tx);
+ }
+ host->removed = true;
+ delay = 0;
+ } else {
+ dev_dbg(mmc_dev(host->mmc), "%s: card inserted\n", __func__);
+ host->removed = false;
+ delay = 500;
+ }
+
+ /*
+ * clearing FIFO interrupts here does not stop a follow up
+ * MSD_FIFO_*RUN after MSD_CARD_CHANGE. instead, check
+ * host->mrq != NULL in moxart_irq to avoid unnecessary calls
+ * to moxart_transfer_pio
+ * if this happens during transfer the mmc_request in
+ * moxart_request should still be valid
+ * (which is why host->mrq can be set NULL here)
+ */
+ host->mrq = NULL;
+ writel(MSD_CARD_CHANGE | MSD_FIFO_ORUN | MSD_FIFO_URUN,
+ &host->reg->clear);
+ writel(MSD_CARD_CHANGE, &host->reg->interrupt_mask);
+
+ spin_unlock_irqrestore(&host->lock, flags);
+ dev_dbg(mmc_dev(host->mmc), "%s: call mmc_detect_change\n", __func__);
+ mmc_detect_change(host->mmc, msecs_to_jiffies(delay));
+}
+
+static void moxart_request(struct mmc_host *mmc, struct mmc_request *mrq)
+{
+ struct moxart_host *host = mmc_priv(mmc);
+ unsigned long dma_time, pio_time, flags;
+ unsigned int status;
+
+ dev_dbg(mmc_dev(host->mmc), "%s\n", __func__);
+
+ spin_lock_irqsave(&host->lock, flags);
+
+ init_completion(&host->dma_complete);
+ init_completion(&host->pio_complete);
+
+ host->mrq = mrq;
+
+ if (readl(&host->reg->status) & MSD_CARD_DETECT) {
+ mrq->cmd->error = MMC_ERR_TIMEOUT;
+ goto request_done;
+ }
+
+ moxart_prepare_data(host);
+ moxart_send_command(host, host->mrq->cmd);
+
+ if (mrq->cmd->data) {
+ /* only use DMA/PIO (and wait) when there is data */
+ if (((host->size > MSD_FIFO_LENB) || DMA_FIFO_LEN_FORCE)
+ && host->have_dma) {
+
+ writel(MSD_CARD_CHANGE, &host->reg->interrupt_mask);
+
+ spin_unlock_irqrestore(&host->lock, flags);
+
+ host->dma_direction = (mrq->cmd->data->flags
+ & MMC_DATA_WRITE) ?
+ DMA_TO_DEVICE : DMA_FROM_DEVICE;
+ host->dma_chan_cur = (mrq->cmd->data->flags
+ & MMC_DATA_WRITE) ?
+ host->dma_chan_tx :
+ host->dma_chan_rx;
+ moxart_transfer_dma(mrq->cmd->data, host);
+
+ dma_time = wait_for_completion_interruptible_timeout(
+ &host->dma_complete, host->timeout);
+ dev_dbg(mmc_dev(host->mmc), "%s: dma_time=%lu (DMA wait time)\n",
+ __func__, dma_time);
+
+ dma_unmap_sg(host->dma_chan_cur->device->dev,
+ mrq->cmd->data->sg, mrq->cmd->data->sg_len,
+ host->dma_direction);
+
+ spin_lock_irqsave(&host->lock, flags);
+ } else {
+
+ writel(MSD_FIFO_URUN | MSD_FIFO_ORUN | MSD_CARD_CHANGE,
+ &host->reg->interrupt_mask);
+
+ status = readl(&host->reg->status);
+ dev_dbg(mmc_dev(host->mmc), "%s: status=%08x\n",
+ __func__, status);
+
+ spin_unlock_irqrestore(&host->lock, flags);
+
+ /* PIO transfer started from interrupt */
+ pio_time = wait_for_completion_interruptible_timeout(
+ &host->pio_complete, host->timeout);
+ dev_dbg(mmc_dev(host->mmc), "%s: pio_time=%lu (PIO wait time)\n",
+ __func__, pio_time);
+
+ spin_lock_irqsave(&host->lock, flags);
+ }
+
+ /* removed during transfer? (interrupts were just enabled..) */
+ if (host->removed) {
+ dev_dbg(mmc_dev(host->mmc), "%s: host removed during transfer!\n",
+ __func__);
+ mrq->cmd->error = MMC_ERR_TIMEOUT;
+ }
+
+ moxart_transfer_check(mrq->cmd->data, host);
+
+ if (mrq->cmd->data->stop)
+ moxart_send_command(host, mrq->cmd->data->stop);
+ }
+
+request_done:
+ spin_unlock_irqrestore(&host->lock, flags);
+ mmc_request_done(host->mmc, mrq);
+}
+
+static irqreturn_t moxart_irq(int irq, void *devid)
+{
+ struct moxart_host *host = (struct moxart_host *)devid;
+ unsigned int status;
+ unsigned long flags;
+
+ status = readl(&host->reg->status);
+
+ dev_dbg(mmc_dev(host->mmc), "%s: host=%p status=%08x\n",
+ __func__, host, status);
+
+ if (status & MSD_CARD_CHANGE) {
+ dev_dbg(mmc_dev(host->mmc), "%s: call moxart_card_change\n",
+ __func__);
+ moxart_card_change(host);
+ }
+ if (status & (MSD_FIFO_ORUN | MSD_FIFO_URUN) && host->mrq) {
+ writel(status & (MSD_FIFO_ORUN | MSD_FIFO_URUN),
+ &host->reg->clear);
+ dev_dbg(mmc_dev(host->mmc), "%s: call moxart_transfer_pio\n",
+ __func__);
+ spin_lock_irqsave(&host->lock, flags);
+ moxart_transfer_pio(host);
+ spin_unlock_irqrestore(&host->lock, flags);
+ }
+
+ return IRQ_HANDLED;
+}
+
+static void moxart_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
+{
+ struct moxart_host *host = mmc_priv(mmc);
+ unsigned long flags;
+ unsigned short power;
+ int div;
+
+ spin_lock_irqsave(&host->lock, flags);
+ if (ios->clock) {
+ div = (host->sysclk / (host->mmc->f_max * 2)) - 1;
+
+ if (div > MSD_CLK_DIV_MASK)
+ div = MSD_CLK_DIV_MASK;
+ else if (div < 0)
+ div = 0;
+
+ div |= MSD_CLK_SD;
+ writel(div, &host->reg->clock_control);
+ } else if (!(readl(&host->reg->clock_control) & MSD_CLK_DIS)) {
+ writel(readl(&host->reg->clock_control) | MSD_CLK_DIS,
+ &host->reg->clock_control);
+ }
+
+ if (ios->power_mode == MMC_POWER_OFF) {
+ writel(readl(&host->reg->power_control) & ~MSD_SD_POWER_ON,
+ &host->reg->power_control);
+ } else {
+ if (ios->vdd < MIN_POWER)
+ power = 0;
+ else
+ power = ios->vdd - MIN_POWER;
+
+ writel(MSD_SD_POWER_ON | (unsigned int) power,
+ &host->reg->power_control);
+ }
+
+ if (ios->bus_width == MMC_BUS_WIDTH_1)
+ writel(MSD_SINGLE_BUS, &host->reg->bus_width);
+ else
+ writel(MSD_WIDE_BUS, &host->reg->bus_width);
+
+ spin_unlock_irqrestore(&host->lock, flags);
+}
+
+
+static int moxart_get_ro(struct mmc_host *mmc)
+{
+ int ret;
+ struct moxart_host *host = mmc_priv(mmc);
+
+ (readl(&host->reg->status) & MSD_WRITE_PROT) ? (ret = 1) : (ret = 0);
+ return ret;
+}
+
+static struct mmc_host_ops moxart_ops = {
+ .request = moxart_request,
+ .set_ios = moxart_set_ios,
+ .get_ro = moxart_get_ro,
+};
+
+static int moxart_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct device_node *node = dev->of_node;
+ struct resource res_mmc;
+ struct mmc_host *mmc;
+ struct moxart_host *host = NULL;
+ void __iomem *reg_mmc;
+ dma_cap_mask_t mask;
+ int ret;
+ struct dma_slave_config cfg;
+ unsigned int irq;
+ struct clk *clk;
+ unsigned int dma_chan_rx_req = 1;
+ unsigned int dma_chan_tx_req = 0;
+
+ mmc = mmc_alloc_host(sizeof(struct moxart_host), dev);
+ if (!mmc) {
+ dev_err(dev, "%s: mmc_alloc_host failed\n", __func__);
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ ret = of_address_to_resource(node, 0, &res_mmc);
+ if (ret) {
+ dev_err(dev, "%s: could not get MMC base resource\n", __func__);
+ goto out;
+ }
+
+ irq = irq_of_parse_and_map(node, 0);
+
+ reg_mmc = devm_ioremap_resource(dev, &res_mmc);
+ if (IS_ERR(reg_mmc)) {
+ dev_err(dev, "%s: devm_ioremap_resource res_mmc failed\n",
+ __func__);
+ return PTR_ERR(reg_mmc);
+ }
+
+ mmc->ops = &moxart_ops;
+
+ /*
+ * hardware does not support MMC_CAP_SD_HIGHSPEED
+ * CMD6 will timeout and make things not work
+ */
+ mmc->caps = MMC_CAP_4_BIT_DATA;
+
+ mmc->f_min = 400000;
+ mmc->f_max = 25000000;
+ mmc->ocr_avail = 0xffff00; /* support 2.0v - 3.6v power */
+ mmc->max_segs = 32;
+ mmc->max_blk_size = 512;
+ mmc->max_blk_count = mmc->max_req_size / mmc->max_blk_size;
+ mmc->max_seg_size = mmc->max_req_size;
+
+ host = mmc_priv(mmc);
+ host->mmc = mmc;
+ host->reg = (struct moxart_reg *)reg_mmc;
+ host->reg_phys = res_mmc.start;
+ host->timeout = msecs_to_jiffies(1000);
+
+ dma_cap_zero(mask);
+ dma_cap_set(DMA_SLAVE, mask);
+
+ clk = of_clk_get(node, 0);
+ if (IS_ERR(clk)) {
+ dev_err(dev, "%s: of_clk_get failed\n", __func__);
+ return PTR_ERR(clk);
+ }
+ host->sysclk = clk_get_rate(clk);
+
+ spin_lock_init(&host->lock);
+
+ /* disable all interrupt */
+ writel(0, &host->reg->interrupt_mask);
+
+ /* reset chip */
+ writel(MSD_SDC_RST, &host->reg->command);
+
+ /* wait for reset finished */
+ while (readl(&host->reg->command) & MSD_SDC_RST)
+ udelay(10);
+
+ host->dma_chan_tx = dma_request_channel(mask, moxart_filter_fn,
+ (void *)&dma_chan_tx_req);
+ host->dma_chan_rx = dma_request_channel(mask, moxart_filter_fn,
+ (void *)&dma_chan_rx_req);
+ dev_dbg(dev, "%s: using 2 DMA channels rx=%p tx=%p\n",
+ __func__, host->dma_chan_rx, host->dma_chan_tx);
+
+ if (!host->dma_chan_rx || !host->dma_chan_tx) {
+ host->have_dma = false;
+ mmc->max_blk_count = 1;
+ } else {
+ cfg.slave_id = APB_DMA_SD_REQ_NO;
+ cfg.direction = DMA_MEM_TO_DEV;
+ cfg.src_addr = 0;
+ cfg.dst_addr = (unsigned int)host->reg_phys + MSD_DATA_WIN_REG;
+ cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+ dmaengine_slave_config(host->dma_chan_tx, &cfg);
+
+ cfg.slave_id = APB_DMA_SD_REQ_NO;
+ cfg.direction = DMA_DEV_TO_MEM;
+ cfg.src_addr = (unsigned int)host->reg_phys + MSD_DATA_WIN_REG;
+ cfg.dst_addr = 0;
+ cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+ dmaengine_slave_config(host->dma_chan_rx, &cfg);
+
+ host->have_dma = true;
+
+ /*
+ * there seems to be a max size on transfers so
+ * set max_blk_count low for both DMA and PIO
+ *
+ * sending large chunks result either in timeout
+ * or render the MMC controller unresponsive
+ * (status register 0 on consecutive read retries,
+ * also see comments in moxart_send_command)
+ *
+ * obviously, DMA is quicker and can handle
+ * larger chunks but setting it higher than 16
+ * can still bug the controller
+ */
+ mmc->max_blk_count = 16;
+ }
+
+ devm_request_irq(dev, irq, moxart_irq, 0, "moxart-mmc", host);
+
+ if (ret)
+ goto out;
+
+ dev_set_drvdata(dev, mmc);
+ mmc_add_host(mmc);
+
+ dev_dbg(dev, "%s: IRQ=%d\n", __func__, irq);
+
+ return 0;
+
+out:
+ if (mmc)
+ mmc_free_host(mmc);
+ return ret;
+}
+
+static void moxart_release_dma(struct moxart_host *host)
+{
+ if (host->dma_chan_tx) {
+ struct dma_chan *chan = host->dma_chan_tx;
+ host->dma_chan_tx = NULL;
+ dma_release_channel(chan);
+ }
+ if (host->dma_chan_rx) {
+ struct dma_chan *chan = host->dma_chan_rx;
+ host->dma_chan_rx = NULL;
+ dma_release_channel(chan);
+ }
+}
+
+static int moxart_remove(struct platform_device *pdev)
+{
+ struct mmc_host *mmc = dev_get_drvdata(&pdev->dev);
+ struct moxart_host *host = mmc_priv(mmc);
+
+ if (mmc) {
+ moxart_release_dma(host);
+ mmc_remove_host(mmc);
+ mmc_free_host(mmc);
+
+ writel(0, &host->reg->interrupt_mask);
+ writel(0, &host->reg->power_control);
+ writel(readl(&host->reg->clock_control) | MSD_CLK_DIS,
+ &host->reg->clock_control);
+ }
+
+ kfree(host);
+
+ return 0;
+}
+
+static const struct of_device_id moxart_mmc_match[] = {
+ { .compatible = "moxa,moxart-mmc" },
+ { }
+};
+
+static struct platform_driver moxart_mmc_driver = {
+ .probe = moxart_probe,
+ .remove = moxart_remove,
+ .driver = {
+ .name = "sdhci-moxart",
+ .owner = THIS_MODULE,
+ .of_match_table = moxart_mmc_match,
+ },
+};
+module_platform_driver(moxart_mmc_driver);
+
+MODULE_ALIAS("platform:sdhci-moxart");
+MODULE_DESCRIPTION("MOXART SDHCI driver");
+MODULE_VERSION("1.0");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Jonas Jensen <[email protected]>");
diff --git a/drivers/mmc/host/sdhci-moxart.h b/drivers/mmc/host/sdhci-moxart.h
new file mode 100644
index 0000000..7269d40
--- /dev/null
+++ b/drivers/mmc/host/sdhci-moxart.h
@@ -0,0 +1,155 @@
+/*
+ * MOXA ART MMC host driver.
+ *
+ * Copyright (C) 2013 Jonas Jensen
+ *
+ * Jonas Jensen <[email protected]>
+ *
+ * Based on code from
+ * Moxa Technology Co., Ltd. <http://www.moxa.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#ifndef _SDHCI_MOXART_H
+#define _SDHCI_MOXART_H
+
+extern bool moxart_filter_fn(struct dma_chan *chan, void *param);
+
+#define MSD_CMD_REG 0
+#define MSD_ARG_REG 4
+#define MSD_RESP0_REG 8
+#define MSD_RESP1_REG 0x0c
+#define MSD_RESP2_REG 0x10
+#define MSD_RESP3_REG 0x14
+#define MSD_RESP_CMD_REG 0x18
+#define MSD_DATA_CTRL_REG 0x1c
+#define MSD_DATA_TIMER_REG 0x20
+#define MSD_DATA_LEN_REG 0x24
+#define MSD_STATUS_REG 0x28
+#define MSD_CLEAR_REG 0x2c
+#define MSD_INT_MASK_REG 0x30
+#define MSD_POWER_CTRL_REG 0x34
+#define MSD_CLOCK_CTRL_REG 0x38
+#define MSD_BUS_WIDTH_REG 0x3c
+#define MSD_DATA_WIN_REG 0x40
+#define MSD_FEATURE_REG 0x44
+#define MSD_REVISION_REG 0x48
+
+#define MMC_RSP_SHORT 1
+#define MMC_RSP_LONG 2
+#define MMC_RSP_MASK 3
+#define MMC_ERR_NONE 0
+#define MMC_ERR_TIMEOUT 1
+#define MMC_MODE_MMC 0
+#define MMC_MODE_SD 1
+#define MMC_ERR_BADCRC 2
+#define MMC_VDD_360 23
+
+#define MSD_RETRY_COUNT 10
+
+struct moxart_reg {
+
+#define MSD_SDC_RST BIT(10)
+#define MSD_CMD_EN BIT(9)
+#define MSD_APP_CMD BIT(8)
+#define MSD_LONG_RSP BIT(7)
+#define MSD_NEED_RSP BIT(6)
+#define MSD_CMD_IDX_MASK 0x3f
+ unsigned int command;
+
+ unsigned int argument;
+ unsigned int response0;
+ unsigned int response1;
+ unsigned int response2;
+ unsigned int response3;
+
+#define MSD_RSP_CMD_APP BIT(6)
+#define MSD_RSP_CMD_IDX_MASK 0x3f
+ unsigned int response_command;
+
+#define MSD_DATA_EN BIT(6)
+#define MSD_DMA_EN BIT(5)
+#define MSD_DATA_WRITE BIT(4)
+#define MSD_BLK_SIZE_MASK 0x0f
+ unsigned int data_control;
+
+ unsigned int data_timer;
+
+#define MSD_DATA_LEN_MASK 0xffffff
+ unsigned int data_length;
+
+#define MSD_WRITE_PROT BIT(12)
+#define MSD_CARD_DETECT BIT(11)
+/* 1-10 below can be sent to interrupt or clear register */
+#define MSD_CARD_CHANGE BIT(10)
+#define MSD_FIFO_ORUN BIT(9)
+#define MSD_FIFO_URUN BIT(8)
+#define MSD_DATA_END BIT(7)
+#define MSD_CMD_SENT BIT(6)
+#define MSD_DATA_CRC_OK BIT(5)
+#define MSD_RSP_CRC_OK BIT(4)
+#define MSD_DATA_TIMEOUT BIT(3)
+#define MSD_RSP_TIMEOUT BIT(2)
+#define MSD_DATA_CRC_FAIL BIT(1)
+#define MSD_RSP_CRC_FAIL BIT(0)
+ unsigned int status;
+
+ unsigned int clear;
+ unsigned int interrupt_mask;
+
+#define MSD_SD_POWER_ON BIT(4)
+#define MSD_SD_POWER_MASK 0x0f
+ unsigned int power_control;
+
+#define MSD_CLK_DIS BIT(8)
+#define MSD_CLK_SD BIT(7)
+#define MSD_CLK_DIV_MASK 0x7f
+ unsigned int clock_control;
+
+#define MSD_WIDE_BUS_SUPPORT BIT(3)
+#define MSD_WIDE_BUS BIT(2) /* bus width is 4 bytes */
+#define MSD_SINGLE_BUS BIT(0) /* bus width is 1 byte */
+ unsigned int bus_width;
+
+ unsigned int data_window;
+
+#define MSD_CPRM_FUNCTION BIT(8)
+ unsigned int feature;
+
+ unsigned int revision;
+};
+
+struct moxart_host {
+ spinlock_t lock;
+ struct moxart_reg *reg;
+ phys_addr_t reg_phys;
+
+ struct dma_chan *dma_chan_rx;
+ struct dma_chan *dma_chan_tx;
+ struct dma_chan *dma_chan_cur;
+ unsigned int dma_direction;
+ bool have_dma;
+ struct completion dma_complete;
+ struct completion pio_complete;
+
+ struct mmc_host *mmc;
+ struct mmc_request *mrq;
+
+ struct scatterlist *cur_sg;
+ unsigned int num_sg;
+ unsigned int remain;
+ int size;
+
+ unsigned int wait_for;
+ unsigned int timeout;
+ long sysclk;
+ bool removed;
+};
+
+#define MSD_FIFO_LENW 4 /* 4 words, total 4 * 4 = 16 bytes */
+#define MSD_FIFO_LENB 16 /* 16 bytes */
+
+#endif /* _SDHCI_MOXART_H */
--
1.8.2.1

2013-07-29 10:50:13

by Jonas Jensen

Subject: [PATCH v3] mmc: sdhci-moxart: Add MOXA ART SDHCI driver

Add SDHCI driver for MOXA ART SoCs.

Signed-off-by: Jonas Jensen <[email protected]>
---

Notes:
Changes since v2:

1. #include <linux/bitops.h> because BIT() comes from there
2. reinsert dev_set_drvdata() in moxart_remove
3. remove MODULE_VERSION()

device tree bindings document:
4. describe compatible variable "Must be" instead of "Should be".
5. change description so it's from the point of view of the device

Applies to next-20130729

.../devicetree/bindings/mmc/moxa,moxart-mmc.txt | 17 +
drivers/mmc/host/Kconfig | 9 +
drivers/mmc/host/Makefile | 1 +
drivers/mmc/host/sdhci-moxart.c | 782 +++++++++++++++++++++
drivers/mmc/host/sdhci-moxart.h | 155 ++++
5 files changed, 964 insertions(+)
create mode 100644 Documentation/devicetree/bindings/mmc/moxa,moxart-mmc.txt
create mode 100644 drivers/mmc/host/sdhci-moxart.c
create mode 100644 drivers/mmc/host/sdhci-moxart.h

diff --git a/Documentation/devicetree/bindings/mmc/moxa,moxart-mmc.txt b/Documentation/devicetree/bindings/mmc/moxa,moxart-mmc.txt
new file mode 100644
index 0000000..67782ad
--- /dev/null
+++ b/Documentation/devicetree/bindings/mmc/moxa,moxart-mmc.txt
@@ -0,0 +1,17 @@
+MOXA ART SD Host Controller Interface
+
+Required properties:
+
+- compatible : Must be "moxa,moxart-mmc"
+- reg : Should contain registers location and length
+- interrupts : Should contain the interrupt number
+- clocks : Should contain phandle for the clock feeding the SDHCI controller
+
+Example:
+
+ mmc: mmc@98e00000 {
+ compatible = "moxa,moxart-mmc";
+ reg = <0x98e00000 0x5C>;
+ interrupts = <5 0>;
+ clocks = <&coreclk>;
+ };
diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
index 8a4c066..3c246390 100644
--- a/drivers/mmc/host/Kconfig
+++ b/drivers/mmc/host/Kconfig
@@ -271,6 +271,15 @@ config MMC_SDHCI_BCM2835

If unsure, say N.

+config MMC_SDHCI_MOXART
+ tristate "MOXART SD Host Controller Interface support"
+ depends on ARCH_MOXART && MMC
+ help
+ This selects the MOXART SD Host Controller Interface.
+ MOXA provides one multi-functional card reader which can
+ be found on some embedded hardware such as UC-7112-LX.
+ If you have a controller with this interface, say Y here.
+
config MMC_OMAP
tristate "TI OMAP Multimedia Card Interface support"
depends on ARCH_OMAP
diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
index d422e21..c91317f 100644
--- a/drivers/mmc/host/Makefile
+++ b/drivers/mmc/host/Makefile
@@ -63,6 +63,7 @@ obj-$(CONFIG_MMC_SDHCI_OF_ESDHC) += sdhci-of-esdhc.o
obj-$(CONFIG_MMC_SDHCI_OF_HLWD) += sdhci-of-hlwd.o
obj-$(CONFIG_MMC_SDHCI_BCM_KONA) += sdhci-bcm-kona.o
obj-$(CONFIG_MMC_SDHCI_BCM2835) += sdhci-bcm2835.o
+obj-$(CONFIG_MMC_SDHCI_MOXART) += sdhci-moxart.o

ifeq ($(CONFIG_CB710_DEBUG),y)
CFLAGS-cb710-mmc += -DDEBUG
diff --git a/drivers/mmc/host/sdhci-moxart.c b/drivers/mmc/host/sdhci-moxart.c
new file mode 100644
index 0000000..fa9056c
--- /dev/null
+++ b/drivers/mmc/host/sdhci-moxart.c
@@ -0,0 +1,782 @@
+/*
+ * MOXA ART MMC host driver.
+ *
+ * Copyright (C) 2013 Jonas Jensen
+ *
+ * Jonas Jensen <[email protected]>
+ *
+ * Based on code from
+ * Moxa Technology Co., Ltd. <http://www.moxa.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/version.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/ioport.h>
+#include <linux/platform_device.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/blkdev.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
+#include <linux/mmc/host.h>
+#include <linux/mmc/sd.h>
+#include <linux/mmc/mmc.h>
+#include <linux/sched.h>
+#include <linux/io.h>
+#include <linux/gpio.h>
+#include <linux/sizes.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/clk.h>
+#include <linux/bitops.h>
+
+#include <asm/dma.h>
+#include <asm/irq.h>
+
+#include "sdhci-moxart.h"
+
+#define DMA_FIFO_LEN_FORCE 0
+#define APB_DMA_SD_REQ_NO 5
+#define MIN_POWER (MMC_VDD_360 - MSD_SD_POWER_MASK)
+
+static inline void moxart_init_sg(struct moxart_host *host,
+ struct mmc_data *data)
+{
+ host->cur_sg = data->sg;
+ host->num_sg = data->sg_len;
+ host->remain = host->cur_sg->length;
+
+ if (host->remain > host->size)
+ host->remain = host->size;
+
+ data->error = MMC_ERR_NONE;
+}
+
+static inline int moxart_next_sg(struct moxart_host *host)
+{
+ int remain;
+ struct mmc_data *data = host->mrq->cmd->data;
+
+ host->cur_sg++;
+ host->num_sg--;
+
+ if (host->num_sg > 0) {
+ host->remain = host->cur_sg->length;
+ remain = host->size - data->bytes_xfered;
+ if (remain > 0 && remain < host->remain)
+ host->remain = remain;
+ }
+
+ return host->num_sg;
+}
+
+static void moxart_send_command(struct moxart_host *host,
+ struct mmc_command *cmd)
+{
+ unsigned int status, cmdctrl;
+ int retry = 0;
+
+ dev_dbg(mmc_dev(host->mmc), "%s: cmd->opcode=%d\n",
+ __func__, cmd->opcode);
+
+ cmd->error = MMC_ERR_TIMEOUT;
+
+ writel(MSD_RSP_TIMEOUT | MSD_RSP_CRC_OK |
+ MSD_RSP_CRC_FAIL | MSD_CMD_SENT, &host->reg->clear);
+ writel(cmd->arg, &host->reg->argument);
+
+ cmdctrl = cmd->opcode & MSD_CMD_IDX_MASK;
+ if (cmdctrl == SD_APP_SET_BUS_WIDTH || cmdctrl == SD_APP_OP_COND ||
+ cmdctrl == SD_APP_SEND_SCR || cmdctrl == SD_APP_SD_STATUS ||
+ cmdctrl == SD_APP_SEND_NUM_WR_BLKS)
+ cmdctrl |= MSD_APP_CMD;
+
+ if (cmd->flags & MMC_RSP_136)
+ cmdctrl |= (MSD_LONG_RSP | MSD_NEED_RSP);
+ else
+ cmdctrl |= MSD_NEED_RSP;
+
+ writel(cmdctrl | MSD_CMD_EN, &host->reg->command);
+
+ while (retry++ < MSD_RETRY_COUNT) {
+ udelay(10);
+ status = readl(&host->reg->status);
+ if (status & MSD_CARD_DETECT) {
+ dev_dbg(mmc_dev(host->mmc), "%s: MSD_CARD_DETECT\n",
+ __func__);
+ cmd->error = MMC_ERR_TIMEOUT;
+ break;
+ }
+ if (cmdctrl & MSD_NEED_RSP) {
+ dev_dbg(mmc_dev(host->mmc), "%s: MSD_NEED_RSP\n",
+ __func__);
+ if (status & MSD_RSP_TIMEOUT) {
+ dev_dbg(mmc_dev(host->mmc), "%s: MSD_RSP_TIMEOUT\n",
+ __func__);
+ writel(MSD_RSP_TIMEOUT, &host->reg->clear);
+ cmd->error = MMC_ERR_TIMEOUT;
+ break;
+ }
+ if ((cmd->flags & MMC_RSP_CRC) &&
+ (status & MSD_RSP_CRC_FAIL)) {
+ dev_dbg(mmc_dev(host->mmc), "%s: MSD_RSP_CRC_FAIL\n",
+ __func__);
+ writel(MSD_RSP_CRC_FAIL, &host->reg->clear);
+ cmd->error = MMC_ERR_BADCRC;
+ break;
+ }
+ if (status & MSD_RSP_CRC_OK) {
+ dev_dbg(mmc_dev(host->mmc), "%s: MSD_RSP_CRC_OK\n",
+ __func__);
+ writel(MSD_RSP_CRC_OK, &host->reg->clear);
+
+ if (cmd->flags & MMC_RSP_136) {
+ cmd->resp[3] =
+ readl(&host->reg->response0);
+ cmd->resp[2] =
+ readl(&host->reg->response1);
+ cmd->resp[1] =
+ readl(&host->reg->response2);
+ cmd->resp[0] =
+ readl(&host->reg->response3);
+ } else {
+ cmd->resp[0] =
+ readl(&host->reg->response0);
+ }
+
+ cmd->error = MMC_ERR_NONE;
+ break;
+ }
+ } else {
+ dev_dbg(mmc_dev(host->mmc), "%s: !(cmdctrl & MSD_NEED_RSP)\n",
+ __func__);
+ if (status & MSD_CMD_SENT) {
+ writel(MSD_CMD_SENT, &host->reg->clear);
+ cmd->error = MMC_ERR_NONE;
+ break;
+ }
+ }
+ }
+
+ if (retry >= (MSD_RETRY_COUNT - 1)) {
+ /*
+ * this seems to happen a lot on or after CMD25
+ * (MMC_WRITE_MULTIPLE_BLOCK) with more than 4 blocks
+ * (>4096), possibly because the transfer is too big
+ * or takes too long to complete.
+ * when this happens the controller is usually rendered
+ * unresponsive and can only be recovered with reboot.
+ */
+ dev_dbg(mmc_dev(host->mmc), "%s: WARNING! no valid status found!\n",
+ __func__);
+ }
+}
+
+static void moxart_dma_complete(void *param)
+{
+ struct moxart_host *host = param;
+
+ dev_dbg(mmc_dev(host->mmc), "%s: host=%p\n", __func__, host);
+ complete(&host->dma_complete);
+}
+
+static void moxart_transfer_dma(struct mmc_data *data, struct moxart_host *host)
+{
+ unsigned int len, direction_dev;
+ struct dma_async_tx_descriptor *desc = NULL;
+
+ if (host->size == data->bytes_xfered)
+ return;
+
+ direction_dev = (data->flags & MMC_DATA_WRITE) ?
+ DMA_MEM_TO_DEV : DMA_DEV_TO_MEM;
+
+ /*
+ * because dma_map_sg takes both sg and sg_len as arguments
+ * (and maps the entire list of buffers) data->sg does not
+ * have to be incremented between calls (as is required
+ * in moxart_transfer_pio)
+ */
+ len = dma_map_sg(host->dma_chan_cur->device->dev, data->sg,
+ data->sg_len, host->dma_direction);
+
+ if (len > 0) {
+ /* host->dma_active = true;*/
+ desc = dmaengine_prep_slave_sg(host->dma_chan_cur, data->sg,
+ len, direction_dev,
+ DMA_PREP_INTERRUPT |
+ DMA_CTRL_ACK);
+ } else {
+ pr_err("%s: dma_map_sg returned zero length\n",
+ __func__);
+ }
+
+ if (desc) {
+ desc->callback = moxart_dma_complete;
+ desc->callback_param = host;
+ dmaengine_submit(desc);
+ dma_async_issue_pending(host->dma_chan_cur);
+ }
+
+ data->bytes_xfered += host->remain;
+}
+
+/* when DMA is available this is used only for SD_APP_SEND_SCR */
+static void moxart_transfer_pio(struct moxart_host *host)
+{
+ unsigned char *buffer;
+ unsigned int wcnt, i;
+ struct mmc_data *data = host->mrq->cmd->data;
+
+ if (host->size == data->bytes_xfered)
+ goto transfer_complete;
+
+ buffer = sg_virt(host->cur_sg);
+ wcnt = host->remain >> 2;
+
+ if (data->flags & MMC_DATA_WRITE) {
+ for (i = 0; i < wcnt; i++, buffer += 4) {
+ writel(*(unsigned int *)buffer,
+ &host->reg->data_window);
+ udelay(10);
+ }
+ } else {
+ for (i = 0; i < wcnt; i++, buffer += 4) {
+ /* byte order reversed only when reading SCR */
+ if (data->mrq->cmd->opcode == SD_APP_SEND_SCR) {
+ *(unsigned int *)buffer = ioread32be(
+ &host->reg->data_window);
+ } else {
+ *(unsigned int *)buffer =
+ readl(&host->reg->data_window);
+ }
+ udelay(10);
+ }
+ }
+ wcnt <<= 2;
+ host->remain -= wcnt;
+ data->bytes_xfered += wcnt;
+
+ if (host->size != data->bytes_xfered) {
+ moxart_next_sg(host);
+ /*
+ * used to goto "transfer_start" label here,
+ * there is no need, this function will be
+ * called again from interrupt.
+ *
+ * compare with DMA where sg increment is
+ * redundant thanks to dma_map_sg
+ */
+ } else {
+ complete(&host->pio_complete);
+ }
+
+transfer_complete:
+ dev_dbg(mmc_dev(host->mmc), "%s: host->size=%d host->remain=%u\n",
+ __func__, host->size, host->remain);
+}
+
+static void moxart_prepare_data(struct moxart_host *host)
+{
+ struct mmc_data *data = host->mrq->cmd->data;
+ unsigned int timeout, datactrl;
+ int blksz_bits;
+
+ dev_dbg(mmc_dev(host->mmc), "%s\n", __func__);
+
+ if (!data)
+ return;
+
+ host->size = data->blocks * data->blksz;
+ blksz_bits = ffs(data->blksz) - 1;
+ BUG_ON(1 << blksz_bits != data->blksz);
+
+ moxart_init_sg(host, data);
+
+ timeout = (host->mmc->f_max / 1000) * (data->timeout_ns / 1000);
+ timeout *= 2;
+
+ datactrl = (blksz_bits & MSD_BLK_SIZE_MASK) | MSD_DATA_EN;
+
+ if (data->flags & MMC_DATA_WRITE)
+ datactrl |= MSD_DATA_WRITE;
+
+ if (((host->size > MSD_FIFO_LENB) || DMA_FIFO_LEN_FORCE)
+ && host->have_dma) {
+ datactrl |= MSD_DMA_EN;
+ }
+
+ dev_dbg(mmc_dev(host->mmc), "%s: blocks=%d blksz=%d datactrl=0x%08x\n",
+ __func__, data->blocks, data->blksz, datactrl);
+ dev_dbg(mmc_dev(host->mmc), "%s: timeout=%u timeout_ns=%u\n",
+ __func__, timeout, data->timeout_ns);
+
+ writel(timeout, &host->reg->data_timer);
+ writel(host->size, &host->reg->data_length);
+ writel(datactrl, &host->reg->data_control);
+}
+
+static void moxart_transfer_check(struct mmc_data *data,
+ struct moxart_host *host)
+{
+ unsigned int status, count = 0;
+
+ dev_dbg(mmc_dev(host->mmc), "%s\n", __func__);
+
+ while (1) {
+ udelay(10);
+ status = readl(&host->reg->status);
+ if (status & (MSD_DATA_CRC_OK | MSD_DATA_CRC_FAIL
+ | MSD_DATA_END) || count > 10)
+ break;
+ dev_dbg(mmc_dev(host->mmc), "%s: waiting for status=%08x ..\n",
+ __func__, status);
+ count++;
+ }
+ if (status & MSD_DATA_CRC_OK) {
+ dev_dbg(mmc_dev(host->mmc), "%s: MSD_DATA_CRC_OK\n", __func__);
+ writel(MSD_DATA_CRC_OK, &host->reg->clear);
+ }
+ if (status & MSD_DATA_CRC_FAIL) {
+ dev_dbg(mmc_dev(host->mmc), "%s: MSD_DATA_CRC_FAIL\n",
+ __func__);
+ writel(MSD_DATA_CRC_FAIL, &host->reg->clear);
+ data->error = MMC_ERR_TIMEOUT;
+ }
+ if (status & MSD_DATA_END) {
+ dev_dbg(mmc_dev(host->mmc), "%s: MSD_DATA_END\n",
+ __func__);
+ writel(MSD_DATA_END, &host->reg->clear);
+ }
+ if (status & MSD_DATA_TIMEOUT) {
+ dev_dbg(mmc_dev(host->mmc), "%s: MSD_DATA_TIMEOUT\n",
+ __func__);
+ writel(MSD_DATA_TIMEOUT, &host->reg->clear);
+ }
+}
+
+static void moxart_card_change(struct moxart_host *host)
+{
+ int delay;
+ unsigned long flags;
+
+ spin_lock_irqsave(&host->lock, flags);
+
+ if (readl(&host->reg->status) & MSD_CARD_DETECT) {
+ dev_dbg(mmc_dev(host->mmc), "%s: card removed\n", __func__);
+ if (host->have_dma && host->size > MSD_FIFO_LENB) {
+ dev_dbg(mmc_dev(host->mmc), "%s: call dmaengine_terminate_all\n",
+ __func__);
+ dmaengine_terminate_all(host->dma_chan_rx);
+ dmaengine_terminate_all(host->dma_chan_tx);
+ }
+ host->removed = true;
+ delay = 0;
+ } else {
+ dev_dbg(mmc_dev(host->mmc), "%s: card inserted\n", __func__);
+ host->removed = false;
+ delay = 500;
+ }
+
+ /*
+ * clearing FIFO interrupts here does not stop a follow up
+ * MSD_FIFO_*RUN after MSD_CARD_CHANGE. instead, check
+ * host->mrq != NULL in moxart_irq to avoid unnecessary calls
+ * to moxart_transfer_pio
+ * if this happens during transfer the mmc_request in
+ * moxart_request should still be valid
+ * (which is why host->mrq can be set NULL here)
+ */
+ host->mrq = NULL;
+ writel(MSD_CARD_CHANGE | MSD_FIFO_ORUN | MSD_FIFO_URUN,
+ &host->reg->clear);
+ writel(MSD_CARD_CHANGE, &host->reg->interrupt_mask);
+
+ spin_unlock_irqrestore(&host->lock, flags);
+ dev_dbg(mmc_dev(host->mmc), "%s: call mmc_detect_change\n", __func__);
+ mmc_detect_change(host->mmc, msecs_to_jiffies(delay));
+}
+
+static void moxart_request(struct mmc_host *mmc, struct mmc_request *mrq)
+{
+ struct moxart_host *host = mmc_priv(mmc);
+ unsigned long dma_time, pio_time, flags;
+ unsigned int status;
+
+ dev_dbg(mmc_dev(host->mmc), "%s\n", __func__);
+
+ spin_lock_irqsave(&host->lock, flags);
+
+ init_completion(&host->dma_complete);
+ init_completion(&host->pio_complete);
+
+ host->mrq = mrq;
+
+ if (readl(&host->reg->status) & MSD_CARD_DETECT) {
+ mrq->cmd->error = MMC_ERR_TIMEOUT;
+ goto request_done;
+ }
+
+ moxart_prepare_data(host);
+ moxart_send_command(host, host->mrq->cmd);
+
+ if (mrq->cmd->data) {
+ /* only use DMA/PIO (and wait) when there is data */
+ if (((host->size > MSD_FIFO_LENB) || DMA_FIFO_LEN_FORCE)
+ && host->have_dma) {
+
+ writel(MSD_CARD_CHANGE, &host->reg->interrupt_mask);
+
+ spin_unlock_irqrestore(&host->lock, flags);
+
+ host->dma_direction = (mrq->cmd->data->flags
+ & MMC_DATA_WRITE) ?
+ DMA_TO_DEVICE : DMA_FROM_DEVICE;
+ host->dma_chan_cur = (mrq->cmd->data->flags
+ & MMC_DATA_WRITE) ?
+ host->dma_chan_tx :
+ host->dma_chan_rx;
+ moxart_transfer_dma(mrq->cmd->data, host);
+
+ dma_time = wait_for_completion_interruptible_timeout(
+ &host->dma_complete, host->timeout);
+ dev_dbg(mmc_dev(host->mmc), "%s: dma_time=%lu (DMA wait time)\n",
+ __func__, dma_time);
+
+ dma_unmap_sg(host->dma_chan_cur->device->dev,
+ mrq->cmd->data->sg, mrq->cmd->data->sg_len,
+ host->dma_direction);
+
+ spin_lock_irqsave(&host->lock, flags);
+ } else {
+
+ writel(MSD_FIFO_URUN | MSD_FIFO_ORUN | MSD_CARD_CHANGE,
+ &host->reg->interrupt_mask);
+
+ status = readl(&host->reg->status);
+ dev_dbg(mmc_dev(host->mmc), "%s: status=%08x\n",
+ __func__, status);
+
+ spin_unlock_irqrestore(&host->lock, flags);
+
+ /* PIO transfer started from interrupt */
+ pio_time = wait_for_completion_interruptible_timeout(
+ &host->pio_complete, host->timeout);
+ dev_dbg(mmc_dev(host->mmc), "%s: pio_time=%lu (PIO wait time)\n",
+ __func__, pio_time);
+
+ spin_lock_irqsave(&host->lock, flags);
+ }
+
+ /* removed during transfer? (interrupts were just enabled..) */
+ if (host->removed) {
+ dev_dbg(mmc_dev(host->mmc), "%s: host removed during transfer!\n",
+ __func__);
+ mrq->cmd->error = MMC_ERR_TIMEOUT;
+ }
+
+ moxart_transfer_check(mrq->cmd->data, host);
+
+ if (mrq->cmd->data->stop)
+ moxart_send_command(host, mrq->cmd->data->stop);
+ }
+
+request_done:
+ spin_unlock_irqrestore(&host->lock, flags);
+ mmc_request_done(host->mmc, mrq);
+}
+
+static irqreturn_t moxart_irq(int irq, void *devid)
+{
+ struct moxart_host *host = (struct moxart_host *)devid;
+ unsigned int status;
+ unsigned long flags;
+
+ status = readl(&host->reg->status);
+
+ dev_dbg(mmc_dev(host->mmc), "%s: host=%p status=%08x\n",
+ __func__, host, status);
+
+ if (status & MSD_CARD_CHANGE) {
+ dev_dbg(mmc_dev(host->mmc), "%s: call moxart_card_change\n",
+ __func__);
+ moxart_card_change(host);
+ }
+ if (status & (MSD_FIFO_ORUN | MSD_FIFO_URUN) && host->mrq) {
+ writel(status & (MSD_FIFO_ORUN | MSD_FIFO_URUN),
+ &host->reg->clear);
+ dev_dbg(mmc_dev(host->mmc), "%s: call moxart_transfer_pio\n",
+ __func__);
+ spin_lock_irqsave(&host->lock, flags);
+ moxart_transfer_pio(host);
+ spin_unlock_irqrestore(&host->lock, flags);
+ }
+
+ return IRQ_HANDLED;
+}
+
+static void moxart_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
+{
+ struct moxart_host *host = mmc_priv(mmc);
+ unsigned long flags;
+ unsigned short power;
+ int div;
+
+ spin_lock_irqsave(&host->lock, flags);
+ if (ios->clock) {
+ div = (host->sysclk / (host->mmc->f_max * 2)) - 1;
+
+ if (div > MSD_CLK_DIV_MASK)
+ div = MSD_CLK_DIV_MASK;
+ else if (div < 0)
+ div = 0;
+
+ div |= MSD_CLK_SD;
+ writel(div, &host->reg->clock_control);
+ } else if (!(readl(&host->reg->clock_control) & MSD_CLK_DIS)) {
+ writel(readl(&host->reg->clock_control) | MSD_CLK_DIS,
+ &host->reg->clock_control);
+ }
+
+ if (ios->power_mode == MMC_POWER_OFF) {
+ writel(readl(&host->reg->power_control) & ~MSD_SD_POWER_ON,
+ &host->reg->power_control);
+ } else {
+ if (ios->vdd < MIN_POWER)
+ power = 0;
+ else
+ power = ios->vdd - MIN_POWER;
+
+ writel(MSD_SD_POWER_ON | (unsigned int) power,
+ &host->reg->power_control);
+ }
+
+ if (ios->bus_width == MMC_BUS_WIDTH_1)
+ writel(MSD_SINGLE_BUS, &host->reg->bus_width);
+ else
+ writel(MSD_WIDE_BUS, &host->reg->bus_width);
+
+ spin_unlock_irqrestore(&host->lock, flags);
+}
+
+
+static int moxart_get_ro(struct mmc_host *mmc)
+{
+ int ret;
+ struct moxart_host *host = mmc_priv(mmc);
+
+ (readl(&host->reg->status) & MSD_WRITE_PROT) ? (ret = 1) : (ret = 0);
+ return ret;
+}
+
+static struct mmc_host_ops moxart_ops = {
+ .request = moxart_request,
+ .set_ios = moxart_set_ios,
+ .get_ro = moxart_get_ro,
+};
+
+static int moxart_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct device_node *node = dev->of_node;
+ struct resource res_mmc;
+ struct mmc_host *mmc;
+ struct moxart_host *host = NULL;
+ void __iomem *reg_mmc;
+ dma_cap_mask_t mask;
+ int ret;
+ struct dma_slave_config cfg;
+ unsigned int irq;
+ struct clk *clk;
+ unsigned int dma_chan_rx_req = 1;
+ unsigned int dma_chan_tx_req = 0;
+
+ mmc = mmc_alloc_host(sizeof(struct moxart_host), dev);
+ if (!mmc) {
+ dev_err(dev, "%s: mmc_alloc_host failed\n", __func__);
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ ret = of_address_to_resource(node, 0, &res_mmc);
+ if (ret) {
+ dev_err(dev, "%s: could not get MMC base resource\n", __func__);
+ goto out;
+ }
+
+ irq = irq_of_parse_and_map(node, 0);
+
+ reg_mmc = devm_ioremap_resource(dev, &res_mmc);
+ if (IS_ERR(reg_mmc)) {
+ dev_err(dev, "%s: devm_ioremap_resource res_mmc failed\n",
+ __func__);
+ return PTR_ERR(reg_mmc);
+ }
+
+ mmc->ops = &moxart_ops;
+
+ /*
+ * hardware does not support MMC_CAP_SD_HIGHSPEED
+ * CMD6 will timeout and make things not work
+ */
+ mmc->caps = MMC_CAP_4_BIT_DATA;
+
+ mmc->f_min = 400000;
+ mmc->f_max = 25000000;
+ mmc->ocr_avail = 0xffff00; /* support 2.0v - 3.6v power */
+ mmc->max_segs = 32;
+ mmc->max_blk_size = 512;
+ mmc->max_blk_count = mmc->max_req_size / mmc->max_blk_size;
+ mmc->max_seg_size = mmc->max_req_size;
+
+ host = mmc_priv(mmc);
+ host->mmc = mmc;
+ host->reg = (struct moxart_reg *)reg_mmc;
+ host->reg_phys = res_mmc.start;
+ host->timeout = msecs_to_jiffies(1000);
+
+ dma_cap_zero(mask);
+ dma_cap_set(DMA_SLAVE, mask);
+
+ clk = of_clk_get(node, 0);
+ if (IS_ERR(clk)) {
+ dev_err(dev, "%s: of_clk_get failed\n", __func__);
+ return PTR_ERR(clk);
+ }
+ host->sysclk = clk_get_rate(clk);
+
+ spin_lock_init(&host->lock);
+
+ /* disable all interrupt */
+ writel(0, &host->reg->interrupt_mask);
+
+ /* reset chip */
+ writel(MSD_SDC_RST, &host->reg->command);
+
+ /* wait for reset finished */
+ while (readl(&host->reg->command) & MSD_SDC_RST)
+ udelay(10);
+
+ host->dma_chan_tx = dma_request_channel(mask, moxart_filter_fn,
+ (void *)&dma_chan_tx_req);
+ host->dma_chan_rx = dma_request_channel(mask, moxart_filter_fn,
+ (void *)&dma_chan_rx_req);
+ dev_dbg(dev, "%s: using 2 DMA channels rx=%p tx=%p\n",
+ __func__, host->dma_chan_rx, host->dma_chan_tx);
+
+ if (!host->dma_chan_rx || !host->dma_chan_tx) {
+ host->have_dma = false;
+ mmc->max_blk_count = 1;
+ } else {
+ cfg.slave_id = APB_DMA_SD_REQ_NO;
+ cfg.direction = DMA_MEM_TO_DEV;
+ cfg.src_addr = 0;
+ cfg.dst_addr = (unsigned int)host->reg_phys + MSD_DATA_WIN_REG;
+ cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+ dmaengine_slave_config(host->dma_chan_tx, &cfg);
+
+ cfg.slave_id = APB_DMA_SD_REQ_NO;
+ cfg.direction = DMA_DEV_TO_MEM;
+ cfg.src_addr = (unsigned int)host->reg_phys + MSD_DATA_WIN_REG;
+ cfg.dst_addr = 0;
+ cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+ dmaengine_slave_config(host->dma_chan_rx, &cfg);
+
+ host->have_dma = true;
+
+ /*
+ * there seems to be a max size on transfers so
+ * set max_blk_count low for both DMA and PIO
+ *
+ * sending large chunks result either in timeout
+ * or render the MMC controller unresponsive
+ * (status register 0 on consecutive read retries,
+ * also see comments in moxart_send_command)
+ *
+ * obviously, DMA is quicker and can handle
+ * larger chunks but setting it higher than 16
+ * can still bug the controller
+ */
+ mmc->max_blk_count = 16;
+ }
+
+ devm_request_irq(dev, irq, moxart_irq, 0, "moxart-mmc", host);
+
+ if (ret)
+ goto out;
+
+ dev_set_drvdata(dev, mmc);
+ mmc_add_host(mmc);
+
+ dev_dbg(dev, "%s: IRQ=%d\n", __func__, irq);
+
+ return 0;
+
+out:
+ if (mmc)
+ mmc_free_host(mmc);
+ return ret;
+}
+
+static void moxart_release_dma(struct moxart_host *host)
+{
+ if (host->dma_chan_tx) {
+ struct dma_chan *chan = host->dma_chan_tx;
+ host->dma_chan_tx = NULL;
+ dma_release_channel(chan);
+ }
+ if (host->dma_chan_rx) {
+ struct dma_chan *chan = host->dma_chan_rx;
+ host->dma_chan_rx = NULL;
+ dma_release_channel(chan);
+ }
+}
+
+static int moxart_remove(struct platform_device *pdev)
+{
+ struct mmc_host *mmc = dev_get_drvdata(&pdev->dev);
+ struct moxart_host *host = mmc_priv(mmc);
+
+ dev_set_drvdata(&pdev->dev, NULL);
+
+ if (mmc) {
+ moxart_release_dma(host);
+ mmc_remove_host(mmc);
+ mmc_free_host(mmc);
+
+ writel(0, &host->reg->interrupt_mask);
+ writel(0, &host->reg->power_control);
+ writel(readl(&host->reg->clock_control) | MSD_CLK_DIS,
+ &host->reg->clock_control);
+ }
+
+ kfree(host);
+
+ return 0;
+}
+
+static const struct of_device_id moxart_mmc_match[] = {
+ { .compatible = "moxa,moxart-mmc" },
+ { }
+};
+
+static struct platform_driver moxart_mmc_driver = {
+ .probe = moxart_probe,
+ .remove = moxart_remove,
+ .driver = {
+ .name = "sdhci-moxart",
+ .owner = THIS_MODULE,
+ .of_match_table = moxart_mmc_match,
+ },
+};
+module_platform_driver(moxart_mmc_driver);
+
+MODULE_ALIAS("platform:sdhci-moxart");
+MODULE_DESCRIPTION("MOXART SDHCI driver");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Jonas Jensen <[email protected]>");
diff --git a/drivers/mmc/host/sdhci-moxart.h b/drivers/mmc/host/sdhci-moxart.h
new file mode 100644
index 0000000..7269d40
--- /dev/null
+++ b/drivers/mmc/host/sdhci-moxart.h
@@ -0,0 +1,155 @@
+/*
+ * MOXA ART MMC host driver.
+ *
+ * Copyright (C) 2013 Jonas Jensen
+ *
+ * Jonas Jensen <[email protected]>
+ *
+ * Based on code from
+ * Moxa Technology Co., Ltd. <http://www.moxa.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#ifndef _SDHCI_MOXART_H
+#define _SDHCI_MOXART_H
+
+extern bool moxart_filter_fn(struct dma_chan *chan, void *param);
+
+#define MSD_CMD_REG 0
+#define MSD_ARG_REG 4
+#define MSD_RESP0_REG 8
+#define MSD_RESP1_REG 0x0c
+#define MSD_RESP2_REG 0x10
+#define MSD_RESP3_REG 0x14
+#define MSD_RESP_CMD_REG 0x18
+#define MSD_DATA_CTRL_REG 0x1c
+#define MSD_DATA_TIMER_REG 0x20
+#define MSD_DATA_LEN_REG 0x24
+#define MSD_STATUS_REG 0x28
+#define MSD_CLEAR_REG 0x2c
+#define MSD_INT_MASK_REG 0x30
+#define MSD_POWER_CTRL_REG 0x34
+#define MSD_CLOCK_CTRL_REG 0x38
+#define MSD_BUS_WIDTH_REG 0x3c
+#define MSD_DATA_WIN_REG 0x40
+#define MSD_FEATURE_REG 0x44
+#define MSD_REVISION_REG 0x48
+
+#define MMC_RSP_SHORT 1
+#define MMC_RSP_LONG 2
+#define MMC_RSP_MASK 3
+#define MMC_ERR_NONE 0
+#define MMC_ERR_TIMEOUT 1
+#define MMC_MODE_MMC 0
+#define MMC_MODE_SD 1
+#define MMC_ERR_BADCRC 2
+#define MMC_VDD_360 23
+
+#define MSD_RETRY_COUNT 10
+
+struct moxart_reg {
+
+#define MSD_SDC_RST BIT(10)
+#define MSD_CMD_EN BIT(9)
+#define MSD_APP_CMD BIT(8)
+#define MSD_LONG_RSP BIT(7)
+#define MSD_NEED_RSP BIT(6)
+#define MSD_CMD_IDX_MASK 0x3f
+ unsigned int command;
+
+ unsigned int argument;
+ unsigned int response0;
+ unsigned int response1;
+ unsigned int response2;
+ unsigned int response3;
+
+#define MSD_RSP_CMD_APP BIT(6)
+#define MSD_RSP_CMD_IDX_MASK 0x3f
+ unsigned int response_command;
+
+#define MSD_DATA_EN BIT(6)
+#define MSD_DMA_EN BIT(5)
+#define MSD_DATA_WRITE BIT(4)
+#define MSD_BLK_SIZE_MASK 0x0f
+ unsigned int data_control;
+
+ unsigned int data_timer;
+
+#define MSD_DATA_LEN_MASK 0xffffff
+ unsigned int data_length;
+
+#define MSD_WRITE_PROT BIT(12)
+#define MSD_CARD_DETECT BIT(11)
+/* 1-10 below can be sent to interrupt or clear register */
+#define MSD_CARD_CHANGE BIT(10)
+#define MSD_FIFO_ORUN BIT(9)
+#define MSD_FIFO_URUN BIT(8)
+#define MSD_DATA_END BIT(7)
+#define MSD_CMD_SENT BIT(6)
+#define MSD_DATA_CRC_OK BIT(5)
+#define MSD_RSP_CRC_OK BIT(4)
+#define MSD_DATA_TIMEOUT BIT(3)
+#define MSD_RSP_TIMEOUT BIT(2)
+#define MSD_DATA_CRC_FAIL BIT(1)
+#define MSD_RSP_CRC_FAIL BIT(0)
+ unsigned int status;
+
+ unsigned int clear;
+ unsigned int interrupt_mask;
+
+#define MSD_SD_POWER_ON BIT(4)
+#define MSD_SD_POWER_MASK 0x0f
+ unsigned int power_control;
+
+#define MSD_CLK_DIS BIT(8)
+#define MSD_CLK_SD BIT(7)
+#define MSD_CLK_DIV_MASK 0x7f
+ unsigned int clock_control;
+
+#define MSD_WIDE_BUS_SUPPORT BIT(3)
+#define MSD_WIDE_BUS BIT(2) /* bus width is 4 bytes */
+#define MSD_SINGLE_BUS BIT(0) /* bus width is 1 byte */
+ unsigned int bus_width;
+
+ unsigned int data_window;
+
+#define MSD_CPRM_FUNCTION BIT(8)
+ unsigned int feature;
+
+ unsigned int revision;
+};
+
+struct moxart_host {
+ spinlock_t lock;
+ struct moxart_reg *reg;
+ phys_addr_t reg_phys;
+
+ struct dma_chan *dma_chan_rx;
+ struct dma_chan *dma_chan_tx;
+ struct dma_chan *dma_chan_cur;
+ unsigned int dma_direction;
+ bool have_dma;
+ struct completion dma_complete;
+ struct completion pio_complete;
+
+ struct mmc_host *mmc;
+ struct mmc_request *mrq;
+
+ struct scatterlist *cur_sg;
+ unsigned int num_sg;
+ unsigned int remain;
+ int size;
+
+ unsigned int wait_for;
+ unsigned int timeout;
+ long sysclk;
+ bool removed;
+};
+
+#define MSD_FIFO_LENW 4 /* 4 words, total 4 * 4 = 16 bytes */
+#define MSD_FIFO_LENB 16 /* 16 bytes */
+
+#endif /* _SDHCI_MOXART_H */
--
1.8.2.1

2013-07-30 09:09:11

by Mark Rutland

Subject: Re: [PATCH v3] mmc: sdhci-moxart: Add MOXA ART SDHCI driver

On Mon, Jul 29, 2013 at 11:49:34AM +0100, Jonas Jensen wrote:
> Add SDHCI driver for MOXA ART SoCs.
>
> Signed-off-by: Jonas Jensen <[email protected]>
> ---
>
> Notes:
> Changes since v2:
>
> 1. #include <linux/bitops.h> because BIT() comes from there
> 2. reinsert dev_set_drvdata() in moxart_remove
> 3. remove MODULE_VERSION()
>
> device tree bindings document:
> 4. describe compatible variable "Must be" instead of "Should be".
> 5. change description so it's from the point of view of the device
>
> Applies to next-20130729
>
> .../devicetree/bindings/mmc/moxa,moxart-mmc.txt | 17 +
> drivers/mmc/host/Kconfig | 9 +
> drivers/mmc/host/Makefile | 1 +
> drivers/mmc/host/sdhci-moxart.c | 782 +++++++++++++++++++++
> drivers/mmc/host/sdhci-moxart.h | 155 ++++
> 5 files changed, 964 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/mmc/moxa,moxart-mmc.txt
> create mode 100644 drivers/mmc/host/sdhci-moxart.c
> create mode 100644 drivers/mmc/host/sdhci-moxart.h
>
> diff --git a/Documentation/devicetree/bindings/mmc/moxa,moxart-mmc.txt b/Documentation/devicetree/bindings/mmc/moxa,moxart-mmc.txt
> new file mode 100644
> index 0000000..67782ad
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mmc/moxa,moxart-mmc.txt
> @@ -0,0 +1,17 @@
> +MOXA ART SD Host Controller Interface
> +
> +Required properties:
> +
> +- compatible : Must be "moxa,moxart-mmc"
> +- reg : Should contain registers location and length
> +- interrupts : Should contain the interrupt number
> +- clocks : Should contain phandle for the clock feeding the SDHCI controller
> +
> +Example:
> +
> + mmc: mmc@98e00000 {
> + compatible = "moxa,moxart-mmc";
> + reg = <0x98e00000 0x5C>;
> + interrupts = <5 0>;
> + clocks = <&coreclk>;
> + };

This binding looks sensible, but I'd appreciate someone who understands
MMCs checking that this captures the relevant information, as I don't
know much about MMCs.

Most mmc bindings I see have to describe some gpio pins, pinctrl to mux
the relevant pins on from the SoC, etc. Is this a full description of
the hardware supporting all features?

[...]

> +static int moxart_get_ro(struct mmc_host *mmc)
> +{
> + int ret;
> + struct moxart_host *host = mmc_priv(mmc);
> +
> + (readl(&host->reg->status) & MSD_WRITE_PROT) ? (ret = 1) : (ret = 0);
> + return ret;

This looks a little odd, how about something like:

return !!(readl(&host->reg->status) & SD_WRITE_PROT);

> +}
> +
> +static struct mmc_host_ops moxart_ops = {
> + .request = moxart_request,
> + .set_ios = moxart_set_ios,
> + .get_ro = moxart_get_ro,
> +};
> +
> +static int moxart_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct device_node *node = dev->of_node;
> + struct resource res_mmc;
> + struct mmc_host *mmc;
> + struct moxart_host *host = NULL;
> + void __iomem *reg_mmc;
> + dma_cap_mask_t mask;
> + int ret;
> + struct dma_slave_config cfg;
> + unsigned int irq;
> + struct clk *clk;
> + unsigned int dma_chan_rx_req = 1;
> + unsigned int dma_chan_tx_req = 0;
> +
> + mmc = mmc_alloc_host(sizeof(struct moxart_host), dev);
> + if (!mmc) {
> + dev_err(dev, "%s: mmc_alloc_host failed\n", __func__);
> + ret = -ENOMEM;
> + goto out;
> + }
> +
> + ret = of_address_to_resource(node, 0, &res_mmc);
> + if (ret) {
> + dev_err(dev, "%s: could not get MMC base resource\n", __func__);
> + goto out;
> + }
> +
> + irq = irq_of_parse_and_map(node, 0);
> +
> + reg_mmc = devm_ioremap_resource(dev, &res_mmc);
> + if (IS_ERR(reg_mmc)) {
> + dev_err(dev, "%s: devm_ioremap_resource res_mmc failed\n",
> + __func__);
> + return PTR_ERR(reg_mmc);
> + }
> +
> + mmc->ops = &moxart_ops;
> +
> + /*
> + * hardware does not support MMC_CAP_SD_HIGHSPEED
> + * CMD6 will timeout and make things not work
> + */
> + mmc->caps = MMC_CAP_4_BIT_DATA;
> +
> + mmc->f_min = 400000;
> + mmc->f_max = 25000000;
> + mmc->ocr_avail = 0xffff00; /* support 2.0v - 3.6v power */
> + mmc->max_segs = 32;
> + mmc->max_blk_size = 512;
> + mmc->max_blk_count = mmc->max_req_size / mmc->max_blk_size;
> + mmc->max_seg_size = mmc->max_req_size;
> +
> + host = mmc_priv(mmc);
> + host->mmc = mmc;
> + host->reg = (struct moxart_reg *)reg_mmc;
> + host->reg_phys = res_mmc.start;
> + host->timeout = msecs_to_jiffies(1000);
> +
> + dma_cap_zero(mask);
> + dma_cap_set(DMA_SLAVE, mask);
> +
> + clk = of_clk_get(node, 0);
> + if (IS_ERR(clk)) {
> + dev_err(dev, "%s: of_clk_get failed\n", __func__);
> + return PTR_ERR(clk);
> + }
> + host->sysclk = clk_get_rate(clk);
> +
> + spin_lock_init(&host->lock);
> +
> + /* disable all interrupt */
> + writel(0, &host->reg->interrupt_mask);
> +
> + /* reset chip */
> + writel(MSD_SDC_RST, &host->reg->command);
> +
> + /* wait for reset finished */
> + while (readl(&host->reg->command) & MSD_SDC_RST)
> + udelay(10);
> +
> + host->dma_chan_tx = dma_request_channel(mask, moxart_filter_fn,
> + (void *)&dma_chan_tx_req);
> + host->dma_chan_rx = dma_request_channel(mask, moxart_filter_fn,
> + (void *)&dma_chan_rx_req);
> + dev_dbg(dev, "%s: using 2 DMA channels rx=%p tx=%p\n",
> + __func__, host->dma_chan_rx, host->dma_chan_tx);
> +
> + if (!host->dma_chan_rx || !host->dma_chan_tx) {
> + host->have_dma = false;
> + mmc->max_blk_count = 1;
> + } else {
> + cfg.slave_id = APB_DMA_SD_REQ_NO;
> + cfg.direction = DMA_MEM_TO_DEV;
> + cfg.src_addr = 0;
> + cfg.dst_addr = (unsigned int)host->reg_phys + MSD_DATA_WIN_REG;
> + cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
> + dmaengine_slave_config(host->dma_chan_tx, &cfg);
> +
> + cfg.slave_id = APB_DMA_SD_REQ_NO;
> + cfg.direction = DMA_DEV_TO_MEM;
> + cfg.src_addr = (unsigned int)host->reg_phys + MSD_DATA_WIN_REG;
> + cfg.dst_addr = 0;
> + cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
> + dmaengine_slave_config(host->dma_chan_rx, &cfg);
> +
> + host->have_dma = true;
> +
> + /*
> + * there seems to be a max size on transfers so
> + * set max_blk_count low for both DMA and PIO
> + *
> + * sending large chunks result either in timeout
> + * or render the MMC controller unresponsive
> + * (status register 0 on consecutive read retries,
> + * also see comments in moxart_send_command)
> + *
> + * obviously, DMA is quicker and can handle
> + * larger chunks but setting it higher than 16
> + * can still bug the controller
> + */
> + mmc->max_blk_count = 16;
> + }
> +
> + devm_request_irq(dev, irq, moxart_irq, 0, "moxart-mmc", host);
> +
> + if (ret)
> + goto out;

Presumably you meant to record the return code of devm_request_irq?

> +
> + dev_set_drvdata(dev, mmc);
> + mmc_add_host(mmc);
> +
> + dev_dbg(dev, "%s: IRQ=%d\n", __func__, irq);
> +
> + return 0;
> +
> +out:
> + if (mmc)
> + mmc_free_host(mmc);
> + return ret;
> +}

[...]

> +struct moxart_reg {
> +
> +#define MSD_SDC_RST BIT(10)
> +#define MSD_CMD_EN BIT(9)
> +#define MSD_APP_CMD BIT(8)
> +#define MSD_LONG_RSP BIT(7)
> +#define MSD_NEED_RSP BIT(6)
> +#define MSD_CMD_IDX_MASK 0x3f
> + unsigned int command;
> +
> + unsigned int argument;
> + unsigned int response0;
> + unsigned int response1;
> + unsigned int response2;
> + unsigned int response3;
> +
> +#define MSD_RSP_CMD_APP BIT(6)
> +#define MSD_RSP_CMD_IDX_MASK 0x3f
> + unsigned int response_command;
> +
> +#define MSD_DATA_EN BIT(6)
> +#define MSD_DMA_EN BIT(5)
> +#define MSD_DATA_WRITE BIT(4)
> +#define MSD_BLK_SIZE_MASK 0x0f
> + unsigned int data_control;
> +
> + unsigned int data_timer;
> +
> +#define MSD_DATA_LEN_MASK 0xffffff
> + unsigned int data_length;
> +
> +#define MSD_WRITE_PROT BIT(12)
> +#define MSD_CARD_DETECT BIT(11)
> +/* 1-10 below can be sent to interrupt or clear register */
> +#define MSD_CARD_CHANGE BIT(10)
> +#define MSD_FIFO_ORUN BIT(9)
> +#define MSD_FIFO_URUN BIT(8)
> +#define MSD_DATA_END BIT(7)
> +#define MSD_CMD_SENT BIT(6)
> +#define MSD_DATA_CRC_OK BIT(5)
> +#define MSD_RSP_CRC_OK BIT(4)
> +#define MSD_DATA_TIMEOUT BIT(3)
> +#define MSD_RSP_TIMEOUT BIT(2)
> +#define MSD_DATA_CRC_FAIL BIT(1)
> +#define MSD_RSP_CRC_FAIL BIT(0)
> + unsigned int status;
> +
> + unsigned int clear;
> + unsigned int interrupt_mask;
> +
> +#define MSD_SD_POWER_ON BIT(4)
> +#define MSD_SD_POWER_MASK 0x0f
> + unsigned int power_control;
> +
> +#define MSD_CLK_DIS BIT(8)
> +#define MSD_CLK_SD BIT(7)
> +#define MSD_CLK_DIV_MASK 0x7f
> + unsigned int clock_control;
> +
> +#define MSD_WIDE_BUS_SUPPORT BIT(3)
> +#define MSD_WIDE_BUS BIT(2) /* bus width is 4 bytes */
> +#define MSD_SINGLE_BUS BIT(0) /* bus width is 1 byte */
> + unsigned int bus_width;
> +
> + unsigned int data_window;
> +
> +#define MSD_CPRM_FUNCTION BIT(8)
> + unsigned int feature;
> +
> + unsigned int revision;
> +};

I see you're using this to handle your register offsets. This isn't
necessarily portable, as you're relying on the size of unsigned int
being 4 bytes, and that elements aren't padded to a larger size. At the
very least unsigned int should be replaced with u32.

Thanks,
Mark.

2013-08-06 13:57:47

by Jonas Jensen

Subject: [PATCH v4] mmc: sdhci-moxart: Add MOXA ART SDHCI driver

Add SDHCI driver for MOXA ART SoCs.

Signed-off-by: Jonas Jensen <[email protected]>
---

Notes:
Changes since v3:

1. don't rely on structs for register offsets
2. use DT probed DMA, remove extern bool moxart_filter_fn()
3. remove unnecessary ternary operator in moxart_get_ro
4. check return value of devm_request_irq

device tree bindings document:
5. add description of DT DMA node

Applies to next-20130806

.../devicetree/bindings/mmc/moxa,moxart-mmc.txt | 28 +
drivers/mmc/host/Kconfig | 9 +
drivers/mmc/host/Makefile | 1 +
drivers/mmc/host/sdhci-moxart.c | 917 +++++++++++++++++++++
4 files changed, 955 insertions(+)
create mode 100644 Documentation/devicetree/bindings/mmc/moxa,moxart-mmc.txt
create mode 100644 drivers/mmc/host/sdhci-moxart.c

diff --git a/Documentation/devicetree/bindings/mmc/moxa,moxart-mmc.txt b/Documentation/devicetree/bindings/mmc/moxa,moxart-mmc.txt
new file mode 100644
index 0000000..c9ad588
--- /dev/null
+++ b/Documentation/devicetree/bindings/mmc/moxa,moxart-mmc.txt
@@ -0,0 +1,28 @@
+MOXA ART SD Host Controller Interface
+
+Required properties:
+
+- compatible : Must be "moxa,moxart-mmc"
+- reg : Should contain registers location and length
+- interrupts : Should contain the interrupt number
+- clocks : Should contain phandle for the clock feeding the SDHCI controller
+
+Optional properties:
+
+These are optional but required to enable DMA transfer mode:
+
+- dmas : Should contain two DMA channels, line request number must be 5 for
+ both channels
+- dma-names : Must be "tx", "rx"
+
+Example:
+
+ mmc: mmc@98e00000 {
+ compatible = "moxa,moxart-mmc";
+ reg = <0x98e00000 0x5C>;
+ interrupts = <5 0>;
+ clocks = <&coreclk>;
+ dmas = <&dma 0 5>,
+ <&dma 1 5>;
+ dma-names = "tx", "rx";
+ };
diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
index 8a4c066..3c246390 100644
--- a/drivers/mmc/host/Kconfig
+++ b/drivers/mmc/host/Kconfig
@@ -271,6 +271,15 @@ config MMC_SDHCI_BCM2835

If unsure, say N.

+config MMC_SDHCI_MOXART
+ tristate "MOXART SD Host Controller Interface support"
+ depends on ARCH_MOXART && MMC
+ help
+ This selects the MOXART SD Host Controller Interface.
+ MOXA provides one multi-functional card reader which can
+ be found on some embedded hardware such as UC-7112-LX.
+ If you have a controller with this interface, say Y here.
+
config MMC_OMAP
tristate "TI OMAP Multimedia Card Interface support"
depends on ARCH_OMAP
diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
index d422e21..c91317f 100644
--- a/drivers/mmc/host/Makefile
+++ b/drivers/mmc/host/Makefile
@@ -63,6 +63,7 @@ obj-$(CONFIG_MMC_SDHCI_OF_ESDHC) += sdhci-of-esdhc.o
obj-$(CONFIG_MMC_SDHCI_OF_HLWD) += sdhci-of-hlwd.o
obj-$(CONFIG_MMC_SDHCI_BCM_KONA) += sdhci-bcm-kona.o
obj-$(CONFIG_MMC_SDHCI_BCM2835) += sdhci-bcm2835.o
+obj-$(CONFIG_MMC_SDHCI_MOXART) += sdhci-moxart.o

ifeq ($(CONFIG_CB710_DEBUG),y)
CFLAGS-cb710-mmc += -DDEBUG
diff --git a/drivers/mmc/host/sdhci-moxart.c b/drivers/mmc/host/sdhci-moxart.c
new file mode 100644
index 0000000..c8c1807
--- /dev/null
+++ b/drivers/mmc/host/sdhci-moxart.c
@@ -0,0 +1,917 @@
+/*
+ * MOXA ART MMC host driver.
+ *
+ * Copyright (C) 2013 Jonas Jensen
+ *
+ * Jonas Jensen <[email protected]>
+ *
+ * Based on code from
+ * Moxa Technology Co., Ltd. <http://www.moxa.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/version.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/ioport.h>
+#include <linux/platform_device.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/blkdev.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
+#include <linux/mmc/host.h>
+#include <linux/mmc/sd.h>
+#include <linux/mmc/mmc.h>
+#include <linux/sched.h>
+#include <linux/io.h>
+#include <linux/gpio.h>
+#include <linux/sizes.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/clk.h>
+#include <linux/bitops.h>
+#include <linux/of_dma.h>
+
+#include <asm/dma.h>
+#include <asm/irq.h>
+
+#define MSD_CMD_REG 0
+#define MSD_ARG_REG 4
+#define MSD_RESP0_REG 8
+#define MSD_RESP1_REG 0x0c
+#define MSD_RESP2_REG 0x10
+#define MSD_RESP3_REG 0x14
+#define MSD_RESP_CMD_REG 0x18
+#define MSD_DATA_CTRL_REG 0x1c
+#define MSD_DATA_TIMER_REG 0x20
+#define MSD_DATA_LEN_REG 0x24
+#define MSD_STATUS_REG 0x28
+#define MSD_CLEAR_REG 0x2c
+#define MSD_INT_MASK_REG 0x30
+#define MSD_POWER_CTRL_REG 0x34
+#define MSD_CLOCK_CTRL_REG 0x38
+#define MSD_BUS_WIDTH_REG 0x3c
+#define MSD_DATA_WIN_REG 0x40
+#define MSD_FEATURE_REG 0x44
+#define MSD_REVISION_REG 0x48
+
+#define MMC_RSP_SHORT 1
+#define MMC_RSP_LONG 2
+#define MMC_RSP_MASK 3
+#define MMC_ERR_NONE 0
+#define MMC_ERR_TIMEOUT 1
+#define MMC_MODE_MMC 0
+#define MMC_MODE_SD 1
+#define MMC_ERR_BADCRC 2
+#define MMC_VDD_360 23
+
+#define MSD_RETRY_COUNT 10
+
+#define REG_COMMAND 0
+#define REG_ARGUMENT 4
+#define REG_RESPONSE0 8
+#define REG_RESPONSE1 12
+#define REG_RESPONSE2 16
+#define REG_RESPONSE3 20
+#define REG_RESPONSE_COMMAND 24
+#define REG_DATA_CONTROL 28
+#define REG_DATA_TIMER 32
+#define REG_DATA_LENGTH 36
+#define REG_STATUS 40
+#define REG_CLEAR 44
+#define REG_INTERRUPT_MASK 48
+#define REG_POWER_CONTROL 52
+#define REG_CLOCK_CONTROL 56
+#define REG_BUS_WIDTH 60
+#define REG_DATA_WINDOW 64
+#define REG_FEATURE 68
+#define REG_REVISION 72
+
+/* REG_COMMAND */
+#define MSD_SDC_RST BIT(10)
+#define MSD_CMD_EN BIT(9)
+#define MSD_APP_CMD BIT(8)
+#define MSD_LONG_RSP BIT(7)
+#define MSD_NEED_RSP BIT(6)
+#define MSD_CMD_IDX_MASK 0x3f
+
+/* REG_RESPONSE_COMMAND */
+#define MSD_RSP_CMD_APP BIT(6)
+#define MSD_RSP_CMD_IDX_MASK 0x3f
+
+/* REG_DATA_CONTROL */
+#define MSD_DATA_EN BIT(6)
+#define MSD_DMA_EN BIT(5)
+#define MSD_DATA_WRITE BIT(4)
+#define MSD_BLK_SIZE_MASK 0x0f
+
+/* REG_DATA_LENGTH */
+#define MSD_DATA_LEN_MASK 0xffffff
+
+/* REG_STATUS */
+#define MSD_WRITE_PROT BIT(12)
+#define MSD_CARD_DETECT BIT(11)
+/* 1-10 below can be sent to interrupt or clear register */
+#define MSD_CARD_CHANGE BIT(10)
+#define MSD_FIFO_ORUN BIT(9)
+#define MSD_FIFO_URUN BIT(8)
+#define MSD_DATA_END BIT(7)
+#define MSD_CMD_SENT BIT(6)
+#define MSD_DATA_CRC_OK BIT(5)
+#define MSD_RSP_CRC_OK BIT(4)
+#define MSD_DATA_TIMEOUT BIT(3)
+#define MSD_RSP_TIMEOUT BIT(2)
+#define MSD_DATA_CRC_FAIL BIT(1)
+#define MSD_RSP_CRC_FAIL BIT(0)
+
+/* REG_POWER_CONTROL */
+#define MSD_SD_POWER_ON BIT(4)
+#define MSD_SD_POWER_MASK 0x0f
+
+/* REG_CLOCK_CONTROL */
+#define MSD_CLK_DIS BIT(8)
+#define MSD_CLK_SD BIT(7)
+#define MSD_CLK_DIV_MASK 0x7f
+
+/* REG_BUS_WIDTH */
+#define MSD_WIDE_BUS_SUPPORT BIT(3)
+#define MSD_WIDE_BUS BIT(2) /* bus width is 4 bytes */
+#define MSD_SINGLE_BUS BIT(0) /* bus width is 1 byte */
+
+/* REG_FEATURE */
+#define MSD_CPRM_FUNCTION BIT(8)
+
+struct moxart_host {
+ spinlock_t lock;
+ void __iomem *base;
+ phys_addr_t reg_phys;
+
+ struct dma_chan *dma_chan_rx;
+ struct dma_chan *dma_chan_tx;
+ struct dma_chan *dma_chan_cur;
+ unsigned int dma_direction;
+ bool have_dma;
+ struct completion dma_complete;
+ struct completion pio_complete;
+
+ struct mmc_host *mmc;
+ struct mmc_request *mrq;
+
+ struct scatterlist *cur_sg;
+ unsigned int num_sg;
+ unsigned int remain;
+ int size;
+
+ unsigned int wait_for;
+ unsigned int timeout;
+ long sysclk;
+ bool removed;
+};
+
+#define MSD_FIFO_LENW 4 /* 4 words, total 4 * 4 = 16 bytes */
+#define MSD_FIFO_LENB 16 /* 16 bytes */
+
+#define DMA_FIFO_LEN_FORCE 0
+#define MIN_POWER (MMC_VDD_360 - MSD_SD_POWER_MASK)
+
+static inline void moxart_init_sg(struct moxart_host *host,
+ struct mmc_data *data)
+{
+ host->cur_sg = data->sg;
+ host->num_sg = data->sg_len;
+ host->remain = host->cur_sg->length;
+
+ if (host->remain > host->size)
+ host->remain = host->size;
+
+ data->error = MMC_ERR_NONE;
+}
+
+static inline int moxart_next_sg(struct moxart_host *host)
+{
+ int remain;
+ struct mmc_data *data = host->mrq->cmd->data;
+
+ host->cur_sg++;
+ host->num_sg--;
+
+ if (host->num_sg > 0) {
+ host->remain = host->cur_sg->length;
+ remain = host->size - data->bytes_xfered;
+ if (remain > 0 && remain < host->remain)
+ host->remain = remain;
+ }
+
+ return host->num_sg;
+}
+
+static void moxart_send_command(struct moxart_host *host,
+ struct mmc_command *cmd)
+{
+ unsigned int status, cmdctrl;
+ int retry = 0;
+
+ dev_dbg(mmc_dev(host->mmc), "%s: cmd->opcode=%d\n",
+ __func__, cmd->opcode);
+
+ cmd->error = MMC_ERR_TIMEOUT;
+
+ writel(MSD_RSP_TIMEOUT | MSD_RSP_CRC_OK |
+ MSD_RSP_CRC_FAIL | MSD_CMD_SENT, host->base + REG_CLEAR);
+ writel(cmd->arg, host->base + REG_ARGUMENT);
+
+ cmdctrl = cmd->opcode & MSD_CMD_IDX_MASK;
+ if (cmdctrl == SD_APP_SET_BUS_WIDTH || cmdctrl == SD_APP_OP_COND ||
+ cmdctrl == SD_APP_SEND_SCR || cmdctrl == SD_APP_SD_STATUS ||
+ cmdctrl == SD_APP_SEND_NUM_WR_BLKS)
+ cmdctrl |= MSD_APP_CMD;
+
+ if (cmd->flags & MMC_RSP_136)
+ cmdctrl |= (MSD_LONG_RSP | MSD_NEED_RSP);
+ else
+ cmdctrl |= MSD_NEED_RSP;
+
+ writel(cmdctrl | MSD_CMD_EN, host->base + REG_COMMAND);
+
+ while (retry++ < MSD_RETRY_COUNT) {
+ udelay(10);
+ status = readl(host->base + REG_STATUS);
+ if (status & MSD_CARD_DETECT) {
+ dev_dbg(mmc_dev(host->mmc), "%s: MSD_CARD_DETECT\n",
+ __func__);
+ cmd->error = MMC_ERR_TIMEOUT;
+ break;
+ }
+ if (cmdctrl & MSD_NEED_RSP) {
+ dev_dbg(mmc_dev(host->mmc), "%s: MSD_NEED_RSP\n",
+ __func__);
+ if (status & MSD_RSP_TIMEOUT) {
+ dev_dbg(mmc_dev(host->mmc), "%s: MSD_RSP_TIMEOUT\n",
+ __func__);
+ writel(MSD_RSP_TIMEOUT, host->base + REG_CLEAR);
+ cmd->error = MMC_ERR_TIMEOUT;
+ break;
+ }
+ if ((cmd->flags & MMC_RSP_CRC) &&
+ (status & MSD_RSP_CRC_FAIL)) {
+ dev_dbg(mmc_dev(host->mmc), "%s: MSD_RSP_CRC_FAIL\n",
+ __func__);
+ writel(MSD_RSP_CRC_FAIL, host->base +
+ REG_CLEAR);
+ cmd->error = MMC_ERR_BADCRC;
+ break;
+ }
+ if (status & MSD_RSP_CRC_OK) {
+ dev_dbg(mmc_dev(host->mmc), "%s: MSD_RSP_CRC_OK\n",
+ __func__);
+ writel(MSD_RSP_CRC_OK, host->base + REG_CLEAR);
+
+ if (cmd->flags & MMC_RSP_136) {
+ cmd->resp[3] =
+ readl(host->base +
+ REG_RESPONSE0);
+ cmd->resp[2] =
+ readl(host->base +
+ REG_RESPONSE1);
+ cmd->resp[1] =
+ readl(host->base +
+ REG_RESPONSE2);
+ cmd->resp[0] =
+ readl(host->base +
+ REG_RESPONSE3);
+ } else {
+ cmd->resp[0] =
+ readl(host->base +
+ REG_RESPONSE0);
+ }
+
+ cmd->error = MMC_ERR_NONE;
+ break;
+ }
+ } else {
+ dev_dbg(mmc_dev(host->mmc), "%s: !(cmdctrl & MSD_NEED_RSP)\n",
+ __func__);
+ if (status & MSD_CMD_SENT) {
+ writel(MSD_CMD_SENT, host->base + REG_CLEAR);
+ cmd->error = MMC_ERR_NONE;
+ break;
+ }
+ }
+ }
+
+ if (retry >= (MSD_RETRY_COUNT - 1)) {
+ /*
+ * this seems to happen a lot on or after CMD25
+ * (MMC_WRITE_MULTIPLE_BLOCK) with more than 4 blocks
+ * (>4096), possibly because the transfer is too big
+ * or takes too long to complete.
+ * when this happens the controller is usually rendered
+ * unresponsive and can only be recovered with reboot.
+ */
+ dev_dbg(mmc_dev(host->mmc), "%s: WARNING! no valid status found!\n",
+ __func__);
+ }
+}
+
+static void moxart_dma_complete(void *param)
+{
+ struct moxart_host *host = param;
+
+ dev_dbg(mmc_dev(host->mmc), "%s: host=%p\n", __func__, host);
+ complete(&host->dma_complete);
+}
+
+static void moxart_transfer_dma(struct mmc_data *data, struct moxart_host *host)
+{
+ unsigned int len, direction_dev;
+ struct dma_async_tx_descriptor *desc = NULL;
+
+ if (host->size == data->bytes_xfered)
+ return;
+
+ direction_dev = (data->flags & MMC_DATA_WRITE) ?
+ DMA_MEM_TO_DEV : DMA_DEV_TO_MEM;
+
+ /*
+ * because dma_map_sg takes both sg and sg_len as arguments
+ * (and maps the entire list of buffers) data->sg does not
+ * have to be incremented between calls (as is required
+ * in moxart_transfer_pio)
+ */
+ len = dma_map_sg(host->dma_chan_cur->device->dev, data->sg,
+ data->sg_len, host->dma_direction);
+
+ if (len > 0) {
+ desc = dmaengine_prep_slave_sg(host->dma_chan_cur, data->sg,
+ len, direction_dev,
+ DMA_PREP_INTERRUPT |
+ DMA_CTRL_ACK);
+ } else {
+ pr_err("%s: dma_map_sg returned zero length\n",
+ __func__);
+ }
+
+ if (desc) {
+ desc->callback = moxart_dma_complete;
+ desc->callback_param = host;
+ dmaengine_submit(desc);
+ dma_async_issue_pending(host->dma_chan_cur);
+ }
+
+ data->bytes_xfered += host->remain;
+}
+
+/* when DMA is available this is used only for SD_APP_SEND_SCR */
+static void moxart_transfer_pio(struct moxart_host *host)
+{
+ unsigned char *buffer;
+ unsigned int wcnt, i;
+ struct mmc_data *data = host->mrq->cmd->data;
+
+ if (host->size == data->bytes_xfered)
+ goto transfer_complete;
+
+ buffer = sg_virt(host->cur_sg);
+ wcnt = host->remain >> 2;
+
+ if (data->flags & MMC_DATA_WRITE) {
+ for (i = 0; i < wcnt; i++, buffer += 4) {
+ writel(*(unsigned int *)buffer,
+ host->base + REG_DATA_WINDOW);
+ udelay(10);
+ }
+ } else {
+ for (i = 0; i < wcnt; i++, buffer += 4) {
+ /* byte order reversed only when reading SCR */
+ if (data->mrq->cmd->opcode == SD_APP_SEND_SCR) {
+ *(unsigned int *)buffer = ioread32be(
+ host->base + REG_DATA_WINDOW);
+ } else {
+ *(unsigned int *)buffer =
+ readl(host->base + REG_DATA_WINDOW);
+ }
+ udelay(10);
+ }
+ }
+ wcnt <<= 2;
+ host->remain -= wcnt;
+ data->bytes_xfered += wcnt;
+
+ if (host->size != data->bytes_xfered) {
+ moxart_next_sg(host);
+ /*
+ * used to goto "transfer_start" label here,
+ * there is no need, this function will be
+ * called again from interrupt.
+ *
+ * compare with DMA where sg increment is
+ * redundant thanks to dma_map_sg
+ */
+ } else {
+ complete(&host->pio_complete);
+ }
+
+transfer_complete:
+ dev_dbg(mmc_dev(host->mmc), "%s: host->size=%d host->remain=%u\n",
+ __func__, host->size, host->remain);
+}
+
+static void moxart_prepare_data(struct moxart_host *host)
+{
+ struct mmc_data *data = host->mrq->cmd->data;
+ unsigned int timeout, datactrl;
+ int blksz_bits;
+
+ dev_dbg(mmc_dev(host->mmc), "%s\n", __func__);
+
+ if (!data)
+ return;
+
+ host->size = data->blocks * data->blksz;
+ blksz_bits = ffs(data->blksz) - 1;
+ BUG_ON(1 << blksz_bits != data->blksz);
+
+ moxart_init_sg(host, data);
+
+ timeout = (host->mmc->f_max / 1000) * (data->timeout_ns / 1000);
+ timeout *= 2;
+
+ datactrl = (blksz_bits & MSD_BLK_SIZE_MASK) | MSD_DATA_EN;
+
+ if (data->flags & MMC_DATA_WRITE)
+ datactrl |= MSD_DATA_WRITE;
+
+ if (((host->size > MSD_FIFO_LENB) || DMA_FIFO_LEN_FORCE)
+ && host->have_dma) {
+ datactrl |= MSD_DMA_EN;
+ }
+
+ dev_dbg(mmc_dev(host->mmc), "%s: blocks=%d blksz=%d datactrl=0x%08x\n",
+ __func__, data->blocks, data->blksz, datactrl);
+ dev_dbg(mmc_dev(host->mmc), "%s: timeout=%u timeout_ns=%u\n",
+ __func__, timeout, data->timeout_ns);
+
+ writel(timeout, host->base + REG_DATA_TIMER);
+ writel(host->size, host->base + REG_DATA_LENGTH);
+ writel(datactrl, host->base + REG_DATA_CONTROL);
+}
+
+static void moxart_transfer_check(struct mmc_data *data,
+ struct moxart_host *host)
+{
+ unsigned int status, count = 0;
+
+ dev_dbg(mmc_dev(host->mmc), "%s\n", __func__);
+
+ while (1) {
+ udelay(10);
+ status = readl(host->base + REG_STATUS);
+ if (status & (MSD_DATA_CRC_OK | MSD_DATA_CRC_FAIL
+ | MSD_DATA_END) || count > 10)
+ break;
+ dev_dbg(mmc_dev(host->mmc), "%s: waiting for status=%08x ..\n",
+ __func__, status);
+ count++;
+ }
+ if (status & MSD_DATA_CRC_OK) {
+ dev_dbg(mmc_dev(host->mmc), "%s: MSD_DATA_CRC_OK\n", __func__);
+ writel(MSD_DATA_CRC_OK, host->base + REG_CLEAR);
+ }
+ if (status & MSD_DATA_CRC_FAIL) {
+ dev_dbg(mmc_dev(host->mmc), "%s: MSD_DATA_CRC_FAIL\n",
+ __func__);
+ writel(MSD_DATA_CRC_FAIL, host->base + REG_CLEAR);
+ data->error = MMC_ERR_TIMEOUT;
+ }
+ if (status & MSD_DATA_END) {
+ dev_dbg(mmc_dev(host->mmc), "%s: MSD_DATA_END\n",
+ __func__);
+ writel(MSD_DATA_END, host->base + REG_CLEAR);
+ }
+ if (status & MSD_DATA_TIMEOUT) {
+ dev_dbg(mmc_dev(host->mmc), "%s: MSD_DATA_TIMEOUT\n",
+ __func__);
+ writel(MSD_DATA_TIMEOUT, host->base + REG_CLEAR);
+ }
+}
+
+static void moxart_card_change(struct moxart_host *host)
+{
+ int delay;
+ unsigned long flags;
+
+ spin_lock_irqsave(&host->lock, flags);
+
+ if (readl(host->base + REG_STATUS) & MSD_CARD_DETECT) {
+ dev_dbg(mmc_dev(host->mmc), "%s: card removed\n", __func__);
+ if (host->have_dma && host->size > MSD_FIFO_LENB) {
+ dev_dbg(mmc_dev(host->mmc), "%s: call dmaengine_terminate_all\n",
+ __func__);
+ dmaengine_terminate_all(host->dma_chan_rx);
+ dmaengine_terminate_all(host->dma_chan_tx);
+ }
+ host->removed = true;
+ delay = 0;
+ } else {
+ dev_dbg(mmc_dev(host->mmc), "%s: card inserted\n", __func__);
+ host->removed = false;
+ delay = 500;
+ }
+
+ /*
+ * clearing FIFO interrupts here does not stop a follow up
+ * MSD_FIFO_*RUN after MSD_CARD_CHANGE. instead, check
+ * host->mrq != NULL in moxart_irq to avoid unnecessary calls
+ * to moxart_transfer_pio
+ * if this happens during transfer the mmc_request in
+ * moxart_request should still be valid
+ * (which is why host->mrq can be set NULL here)
+ */
+ host->mrq = NULL;
+ writel(MSD_CARD_CHANGE | MSD_FIFO_ORUN | MSD_FIFO_URUN,
+ host->base + REG_CLEAR);
+ writel(MSD_CARD_CHANGE, host->base + REG_INTERRUPT_MASK);
+
+ spin_unlock_irqrestore(&host->lock, flags);
+ dev_dbg(mmc_dev(host->mmc), "%s: call mmc_detect_change\n", __func__);
+ mmc_detect_change(host->mmc, msecs_to_jiffies(delay));
+}
+
+static void moxart_request(struct mmc_host *mmc, struct mmc_request *mrq)
+{
+ struct moxart_host *host = mmc_priv(mmc);
+ unsigned long dma_time, pio_time, flags;
+ unsigned int status;
+
+ dev_dbg(mmc_dev(host->mmc), "%s\n", __func__);
+
+ spin_lock_irqsave(&host->lock, flags);
+
+ init_completion(&host->dma_complete);
+ init_completion(&host->pio_complete);
+
+ host->mrq = mrq;
+
+ if (readl(host->base + REG_STATUS) & MSD_CARD_DETECT) {
+ mrq->cmd->error = MMC_ERR_TIMEOUT;
+ goto request_done;
+ }
+
+ moxart_prepare_data(host);
+ moxart_send_command(host, host->mrq->cmd);
+
+ if (mrq->cmd->data) {
+ /* only use DMA/PIO (and wait) when there is data */
+ if (((host->size > MSD_FIFO_LENB) || DMA_FIFO_LEN_FORCE)
+ && host->have_dma) {
+
+ writel(MSD_CARD_CHANGE, host->base +
+ REG_INTERRUPT_MASK);
+
+ spin_unlock_irqrestore(&host->lock, flags);
+
+ host->dma_direction = (mrq->cmd->data->flags
+ & MMC_DATA_WRITE) ?
+ DMA_TO_DEVICE : DMA_FROM_DEVICE;
+ host->dma_chan_cur = (mrq->cmd->data->flags
+ & MMC_DATA_WRITE) ?
+ host->dma_chan_tx :
+ host->dma_chan_rx;
+ moxart_transfer_dma(mrq->cmd->data, host);
+
+ dma_time = wait_for_completion_interruptible_timeout(
+ &host->dma_complete, host->timeout);
+ dev_dbg(mmc_dev(host->mmc), "%s: dma_time=%lu (DMA wait time)\n",
+ __func__, dma_time);
+
+ dma_unmap_sg(host->dma_chan_cur->device->dev,
+ mrq->cmd->data->sg, mrq->cmd->data->sg_len,
+ host->dma_direction);
+
+ spin_lock_irqsave(&host->lock, flags);
+ } else {
+
+ writel(MSD_FIFO_URUN | MSD_FIFO_ORUN | MSD_CARD_CHANGE,
+ host->base + REG_INTERRUPT_MASK);
+
+ status = readl(host->base + REG_STATUS);
+ dev_dbg(mmc_dev(host->mmc), "%s: status=%08x\n",
+ __func__, status);
+
+ spin_unlock_irqrestore(&host->lock, flags);
+
+ /* PIO transfer started from interrupt */
+ pio_time = wait_for_completion_interruptible_timeout(
+ &host->pio_complete, host->timeout);
+ dev_dbg(mmc_dev(host->mmc), "%s: pio_time=%lu (PIO wait time)\n",
+ __func__, pio_time);
+
+ spin_lock_irqsave(&host->lock, flags);
+ }
+
+ /* removed during transfer? (interrupts were just enabled..) */
+ if (host->removed) {
+ dev_dbg(mmc_dev(host->mmc), "%s: host removed during transfer!\n",
+ __func__);
+ mrq->cmd->error = MMC_ERR_TIMEOUT;
+ }
+
+ moxart_transfer_check(mrq->cmd->data, host);
+
+ if (mrq->cmd->data->stop)
+ moxart_send_command(host, mrq->cmd->data->stop);
+ }
+
+request_done:
+ spin_unlock_irqrestore(&host->lock, flags);
+ mmc_request_done(host->mmc, mrq);
+}
+
+static irqreturn_t moxart_irq(int irq, void *devid)
+{
+ struct moxart_host *host = (struct moxart_host *)devid;
+ unsigned int status;
+ unsigned long flags;
+
+ status = readl(host->base + REG_STATUS);
+
+ dev_dbg(mmc_dev(host->mmc), "%s: host=%p status=%08x\n",
+ __func__, host, status);
+
+ if (status & MSD_CARD_CHANGE) {
+ dev_dbg(mmc_dev(host->mmc), "%s: call moxart_card_change\n",
+ __func__);
+ moxart_card_change(host);
+ }
+ if (status & (MSD_FIFO_ORUN | MSD_FIFO_URUN) && host->mrq) {
+ writel(status & (MSD_FIFO_ORUN | MSD_FIFO_URUN),
+ host->base + REG_CLEAR);
+ dev_dbg(mmc_dev(host->mmc), "%s: call moxart_transfer_pio\n",
+ __func__);
+ spin_lock_irqsave(&host->lock, flags);
+ moxart_transfer_pio(host);
+ spin_unlock_irqrestore(&host->lock, flags);
+ }
+
+ return IRQ_HANDLED;
+}
+
+static void moxart_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
+{
+ struct moxart_host *host = mmc_priv(mmc);
+ unsigned long flags;
+ unsigned short power;
+ int div;
+
+ spin_lock_irqsave(&host->lock, flags);
+ if (ios->clock) {
+ div = (host->sysclk / (host->mmc->f_max * 2)) - 1;
+
+ if (div > MSD_CLK_DIV_MASK)
+ div = MSD_CLK_DIV_MASK;
+ else if (div < 0)
+ div = 0;
+
+ div |= MSD_CLK_SD;
+ writel(div, host->base + REG_CLOCK_CONTROL);
+ } else if (!(readl(host->base + REG_CLOCK_CONTROL) & MSD_CLK_DIS)) {
+ writel(readl(host->base + REG_CLOCK_CONTROL) | MSD_CLK_DIS,
+ host->base + REG_CLOCK_CONTROL);
+ }
+
+ if (ios->power_mode == MMC_POWER_OFF) {
+ writel(readl(host->base + REG_POWER_CONTROL) & ~MSD_SD_POWER_ON,
+ host->base + REG_POWER_CONTROL);
+ } else {
+ if (ios->vdd < MIN_POWER)
+ power = 0;
+ else
+ power = ios->vdd - MIN_POWER;
+
+ writel(MSD_SD_POWER_ON | (unsigned int) power,
+ host->base + REG_POWER_CONTROL);
+ }
+
+ if (ios->bus_width == MMC_BUS_WIDTH_1)
+ writel(MSD_SINGLE_BUS, host->base + REG_BUS_WIDTH);
+ else
+ writel(MSD_WIDE_BUS, host->base + REG_BUS_WIDTH);
+
+ spin_unlock_irqrestore(&host->lock, flags);
+}
+
+
+static int moxart_get_ro(struct mmc_host *mmc)
+{
+ struct moxart_host *host = mmc_priv(mmc);
+
+ return readl(host->base + REG_STATUS) & MSD_WRITE_PROT;
+}
+
+static struct mmc_host_ops moxart_ops = {
+ .request = moxart_request,
+ .set_ios = moxart_set_ios,
+ .get_ro = moxart_get_ro,
+};
+
+static int moxart_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct device_node *node = dev->of_node;
+ struct resource res_mmc;
+ struct mmc_host *mmc;
+ struct moxart_host *host = NULL;
+ void __iomem *reg_mmc;
+ dma_cap_mask_t mask;
+ int ret;
+ struct dma_slave_config cfg;
+ unsigned int irq;
+ struct clk *clk;
+
+ mmc = mmc_alloc_host(sizeof(struct moxart_host), dev);
+ if (!mmc) {
+ dev_err(dev, "%s: mmc_alloc_host failed\n", __func__);
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ ret = of_address_to_resource(node, 0, &res_mmc);
+ if (ret) {
+ dev_err(dev, "%s: could not get MMC base resource\n", __func__);
+ goto out;
+ }
+
+ irq = irq_of_parse_and_map(node, 0);
+
+ reg_mmc = devm_ioremap_resource(dev, &res_mmc);
+ if (IS_ERR(reg_mmc)) {
+ dev_err(dev, "%s: devm_ioremap_resource res_mmc failed\n",
+ __func__);
+ return PTR_ERR(reg_mmc);
+ }
+
+ mmc->ops = &moxart_ops;
+
+ /*
+ * hardware does not support MMC_CAP_SD_HIGHSPEED
+ * CMD6 will timeout and make things not work
+ */
+ mmc->caps = MMC_CAP_4_BIT_DATA;
+
+ mmc->f_min = 400000;
+ mmc->f_max = 25000000;
+ mmc->ocr_avail = 0xffff00; /* support 2.0v - 3.6v power */
+ mmc->max_segs = 32;
+ mmc->max_blk_size = 512;
+ mmc->max_blk_count = mmc->max_req_size / mmc->max_blk_size;
+ mmc->max_seg_size = mmc->max_req_size;
+
+ host = mmc_priv(mmc);
+ host->mmc = mmc;
+ host->base = reg_mmc;
+ host->reg_phys = res_mmc.start;
+ host->timeout = msecs_to_jiffies(1000);
+
+ dma_cap_zero(mask);
+ dma_cap_set(DMA_SLAVE, mask);
+
+ clk = of_clk_get(node, 0);
+ if (IS_ERR(clk)) {
+ dev_err(dev, "%s: of_clk_get failed\n", __func__);
+ return PTR_ERR(clk);
+ }
+ host->sysclk = clk_get_rate(clk);
+
+ spin_lock_init(&host->lock);
+
+ /* disable all interrupt */
+ writel(0, host->base + REG_INTERRUPT_MASK);
+
+ /* reset chip */
+ writel(MSD_SDC_RST, host->base + REG_COMMAND);
+
+ /* wait for reset finished */
+ while (readl(host->base + REG_COMMAND) & MSD_SDC_RST)
+ udelay(10);
+
+ host->dma_chan_tx = of_dma_request_slave_channel(node, "tx");
+ host->dma_chan_rx = of_dma_request_slave_channel(node, "rx");
+
+ if (!host->dma_chan_rx || !host->dma_chan_tx) {
+ dev_dbg(dev, "%s: using PIO mode transfer\n", __func__);
+
+ host->have_dma = false;
+ mmc->max_blk_count = 1;
+ } else {
+ dev_dbg(dev, "%s: using 2 DMA channels rx=%p tx=%p\n",
+ __func__, host->dma_chan_rx, host->dma_chan_tx);
+
+ cfg.direction = DMA_MEM_TO_DEV;
+ cfg.src_addr = 0;
+ cfg.dst_addr = (unsigned int)host->reg_phys + MSD_DATA_WIN_REG;
+ cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+ dmaengine_slave_config(host->dma_chan_tx, &cfg);
+
+ cfg.direction = DMA_DEV_TO_MEM;
+ cfg.src_addr = (unsigned int)host->reg_phys + MSD_DATA_WIN_REG;
+ cfg.dst_addr = 0;
+ cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+ dmaengine_slave_config(host->dma_chan_rx, &cfg);
+
+ host->have_dma = true;
+
+ /*
+ * there seems to be a max size on transfers so
+ * set max_blk_count low for both DMA and PIO
+ *
+ * sending large chunks result either in timeout
+ * or render the MMC controller unresponsive
+ * (status register 0 on consecutive read retries,
+ * also see comments in moxart_send_command)
+ *
+ * obviously, DMA is quicker and can handle
+ * larger chunks but setting it higher than 16
+ * can still bug the controller
+ */
+ mmc->max_blk_count = 16;
+ }
+
+ ret = devm_request_irq(dev, irq, moxart_irq, 0, "moxart-mmc", host);
+
+ if (ret)
+ goto out;
+
+ dev_set_drvdata(dev, mmc);
+ mmc_add_host(mmc);
+
+ dev_dbg(dev, "%s: IRQ=%d\n", __func__, irq);
+
+ return 0;
+
+out:
+ if (mmc)
+ mmc_free_host(mmc);
+ return ret;
+}
+
+static void moxart_release_dma(struct moxart_host *host)
+{
+ if (host->dma_chan_tx) {
+ struct dma_chan *chan = host->dma_chan_tx;
+ host->dma_chan_tx = NULL;
+ dma_release_channel(chan);
+ }
+ if (host->dma_chan_rx) {
+ struct dma_chan *chan = host->dma_chan_rx;
+ host->dma_chan_rx = NULL;
+ dma_release_channel(chan);
+ }
+}
+
+static int moxart_remove(struct platform_device *pdev)
+{
+ struct mmc_host *mmc = dev_get_drvdata(&pdev->dev);
+ struct moxart_host *host = mmc_priv(mmc);
+
+ dev_set_drvdata(&pdev->dev, NULL);
+
+ if (mmc) {
+ moxart_release_dma(host);
+ mmc_remove_host(mmc);
+ mmc_free_host(mmc);
+
+ writel(0, host->base + REG_INTERRUPT_MASK);
+ writel(0, host->base + REG_POWER_CONTROL);
+ writel(readl(host->base + REG_CLOCK_CONTROL) | MSD_CLK_DIS,
+ host->base + REG_CLOCK_CONTROL);
+ }
+
+ kfree(host);
+
+ return 0;
+}
+
+static const struct of_device_id moxart_mmc_match[] = {
+ { .compatible = "moxa,moxart-mmc" },
+ { }
+};
+
+static struct platform_driver moxart_mmc_driver = {
+ .probe = moxart_probe,
+ .remove = moxart_remove,
+ .driver = {
+ .name = "sdhci-moxart",
+ .owner = THIS_MODULE,
+ .of_match_table = moxart_mmc_match,
+ },
+};
+module_platform_driver(moxart_mmc_driver);
+
+MODULE_ALIAS("platform:sdhci-moxart");
+MODULE_DESCRIPTION("MOXART SDHCI driver");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Jonas Jensen <[email protected]>");
--
1.8.2.1