In Mediatek SOCs, the uart can support DMA function.
Base on DMA engine formwork, we add the DMA code to support uart. And put the code under drivers/dma/mediatek.
This series contains document bindings, Kconfig to control the function enable or not,
device tree including interrupt and dma device node, the code of UART DMA
Changes compared to v9
-rename dt-bindings file
-remove direction from device_config
-simplified code
Changes compared to v8
-revise missing items
Changes compared to v7:
-modify apdma uart tx
Changes compared to v6:
-Correct spelling
Changes compared to v5:
-move 'requst irqs' to alloc channel
-remove tasklet.
Changes compared to v4:
-modify Kconfig depends on.
Changes compared to v3:
-fix CONFIG_PM, will cause build fail
Changes compared to v2:
-remove unimportant parameters
-instead of cookie, use APIs of virtual channel.
-use of_dma_xlate_by_chan_id.
Changes compared to v1:
-mian revised file, 8250_mtk_dma.c
--parameters renamed for standard
--remove atomic operation
Long Cheng (3):
dmaengine: 8250_mtk_dma: add MediaTek uart DMA support
arm: dts: mt2712: add uart APDMA to device tree
dt-bindings: dma: uart: rename binding
.../devicetree/bindings/dma/8250_mtk_dma.txt | 33 -
.../devicetree/bindings/dma/mtk-uart-apdma.txt | 33 +
arch/arm64/boot/dts/mediatek/mt2712e.dtsi | 51 ++
drivers/dma/mediatek/Kconfig | 11 +
drivers/dma/mediatek/Makefile | 1 +
drivers/dma/mediatek/mtk-uart-apdma.c | 669 ++++++++++++++++++++
6 files changed, 765 insertions(+), 33 deletions(-)
delete mode 100644 Documentation/devicetree/bindings/dma/8250_mtk_dma.txt
create mode 100644 Documentation/devicetree/bindings/dma/mtk-uart-apdma.txt
create mode 100644 drivers/dma/mediatek/mtk-uart-apdma.c
--
1.7.9.5
The filename matches mtk-uart-apdma.c.
So using "mtk-uart-apdma.txt" should be better.
Signed-off-by: Long Cheng <[email protected]>
---
.../devicetree/bindings/dma/8250_mtk_dma.txt | 33 --------------------
.../devicetree/bindings/dma/mtk-uart-apdma.txt | 33 ++++++++++++++++++++
2 files changed, 33 insertions(+), 33 deletions(-)
delete mode 100644 Documentation/devicetree/bindings/dma/8250_mtk_dma.txt
create mode 100644 Documentation/devicetree/bindings/dma/mtk-uart-apdma.txt
diff --git a/Documentation/devicetree/bindings/dma/8250_mtk_dma.txt b/Documentation/devicetree/bindings/dma/8250_mtk_dma.txt
deleted file mode 100644
index 3fe0961..0000000
--- a/Documentation/devicetree/bindings/dma/8250_mtk_dma.txt
+++ /dev/null
@@ -1,33 +0,0 @@
-* Mediatek UART APDMA Controller
-
-Required properties:
-- compatible should contain:
- * "mediatek,mt2712-uart-dma" for MT2712 compatible APDMA
- * "mediatek,mt6577-uart-dma" for MT6577 and all of the above
-
-- reg: The base address of the APDMA register bank.
-
-- interrupts: A single interrupt specifier.
-
-- clocks : Must contain an entry for each entry in clock-names.
- See ../clocks/clock-bindings.txt for details.
-- clock-names: The APDMA clock for register accesses
-
-Examples:
-
- apdma: dma-controller@11000380 {
- compatible = "mediatek,mt2712-uart-dma";
- reg = <0 0x11000380 0 0x400>;
- interrupts = <GIC_SPI 63 IRQ_TYPE_LEVEL_LOW>,
- <GIC_SPI 64 IRQ_TYPE_LEVEL_LOW>,
- <GIC_SPI 65 IRQ_TYPE_LEVEL_LOW>,
- <GIC_SPI 66 IRQ_TYPE_LEVEL_LOW>,
- <GIC_SPI 67 IRQ_TYPE_LEVEL_LOW>,
- <GIC_SPI 68 IRQ_TYPE_LEVEL_LOW>,
- <GIC_SPI 69 IRQ_TYPE_LEVEL_LOW>,
- <GIC_SPI 70 IRQ_TYPE_LEVEL_LOW>;
- clocks = <&pericfg CLK_PERI_AP_DMA>;
- clock-names = "apdma";
- #dma-cells = <1>;
- };
-
diff --git a/Documentation/devicetree/bindings/dma/mtk-uart-apdma.txt b/Documentation/devicetree/bindings/dma/mtk-uart-apdma.txt
new file mode 100644
index 0000000..3fe0961
--- /dev/null
+++ b/Documentation/devicetree/bindings/dma/mtk-uart-apdma.txt
@@ -0,0 +1,33 @@
+* Mediatek UART APDMA Controller
+
+Required properties:
+- compatible should contain:
+ * "mediatek,mt2712-uart-dma" for MT2712 compatible APDMA
+ * "mediatek,mt6577-uart-dma" for MT6577 and all of the above
+
+- reg: The base address of the APDMA register bank.
+
+- interrupts: A single interrupt specifier.
+
+- clocks : Must contain an entry for each entry in clock-names.
+ See ../clocks/clock-bindings.txt for details.
+- clock-names: The APDMA clock for register accesses
+
+Examples:
+
+ apdma: dma-controller@11000380 {
+ compatible = "mediatek,mt2712-uart-dma";
+ reg = <0 0x11000380 0 0x400>;
+ interrupts = <GIC_SPI 63 IRQ_TYPE_LEVEL_LOW>,
+ <GIC_SPI 64 IRQ_TYPE_LEVEL_LOW>,
+ <GIC_SPI 65 IRQ_TYPE_LEVEL_LOW>,
+ <GIC_SPI 66 IRQ_TYPE_LEVEL_LOW>,
+ <GIC_SPI 67 IRQ_TYPE_LEVEL_LOW>,
+ <GIC_SPI 68 IRQ_TYPE_LEVEL_LOW>,
+ <GIC_SPI 69 IRQ_TYPE_LEVEL_LOW>,
+ <GIC_SPI 70 IRQ_TYPE_LEVEL_LOW>;
+ clocks = <&pericfg CLK_PERI_AP_DMA>;
+ clock-names = "apdma";
+ #dma-cells = <1>;
+ };
+
--
1.7.9.5
1. add uart APDMA controller device node
2. add uart 0/1/2/3/4/5 DMA function
Signed-off-by: Long Cheng <[email protected]>
---
arch/arm64/boot/dts/mediatek/mt2712e.dtsi | 51 +++++++++++++++++++++++++++++
1 file changed, 51 insertions(+)
diff --git a/arch/arm64/boot/dts/mediatek/mt2712e.dtsi b/arch/arm64/boot/dts/mediatek/mt2712e.dtsi
index ee627a7..3469a6c 100644
--- a/arch/arm64/boot/dts/mediatek/mt2712e.dtsi
+++ b/arch/arm64/boot/dts/mediatek/mt2712e.dtsi
@@ -298,6 +298,9 @@
interrupts = <GIC_SPI 127 IRQ_TYPE_LEVEL_LOW>;
clocks = <&baud_clk>, <&sys_clk>;
clock-names = "baud", "bus";
+ dmas = <&apdma 10
+ &apdma 11>;
+ dma-names = "tx", "rx";
status = "disabled";
};
@@ -346,6 +349,39 @@
(GIC_CPU_MASK_RAW(0x13) | IRQ_TYPE_LEVEL_HIGH)>;
};
+ apdma: dma-controller@11000400 {
+ compatible = "mediatek,mt2712-uart-dma",
+ "mediatek,mt6577-uart-dma";
+ reg = <0 0x11000400 0 0x80>,
+ <0 0x11000480 0 0x80>,
+ <0 0x11000500 0 0x80>,
+ <0 0x11000580 0 0x80>,
+ <0 0x11000600 0 0x80>,
+ <0 0x11000680 0 0x80>,
+ <0 0x11000700 0 0x80>,
+ <0 0x11000780 0 0x80>,
+ <0 0x11000800 0 0x80>,
+ <0 0x11000880 0 0x80>,
+ <0 0x11000900 0 0x80>,
+ <0 0x11000980 0 0x80>;
+ interrupts = <GIC_SPI 103 IRQ_TYPE_LEVEL_LOW>,
+ <GIC_SPI 104 IRQ_TYPE_LEVEL_LOW>,
+ <GIC_SPI 105 IRQ_TYPE_LEVEL_LOW>,
+ <GIC_SPI 106 IRQ_TYPE_LEVEL_LOW>,
+ <GIC_SPI 107 IRQ_TYPE_LEVEL_LOW>,
+ <GIC_SPI 108 IRQ_TYPE_LEVEL_LOW>,
+ <GIC_SPI 109 IRQ_TYPE_LEVEL_LOW>,
+ <GIC_SPI 110 IRQ_TYPE_LEVEL_LOW>,
+ <GIC_SPI 111 IRQ_TYPE_LEVEL_LOW>,
+ <GIC_SPI 112 IRQ_TYPE_LEVEL_LOW>,
+ <GIC_SPI 113 IRQ_TYPE_LEVEL_LOW>,
+ <GIC_SPI 114 IRQ_TYPE_LEVEL_LOW>;
+ dma-requests = <12>;
+ clocks = <&pericfg CLK_PERI_AP_DMA>;
+ clock-names = "apdma";
+ #dma-cells = <1>;
+ };
+
auxadc: adc@11001000 {
compatible = "mediatek,mt2712-auxadc";
reg = <0 0x11001000 0 0x1000>;
@@ -362,6 +398,9 @@
interrupts = <GIC_SPI 91 IRQ_TYPE_LEVEL_LOW>;
clocks = <&baud_clk>, <&sys_clk>;
clock-names = "baud", "bus";
+ dmas = <&apdma 0
+ &apdma 1>;
+ dma-names = "tx", "rx";
status = "disabled";
};
@@ -372,6 +411,9 @@
interrupts = <GIC_SPI 92 IRQ_TYPE_LEVEL_LOW>;
clocks = <&baud_clk>, <&sys_clk>;
clock-names = "baud", "bus";
+ dmas = <&apdma 2
+ &apdma 3>;
+ dma-names = "tx", "rx";
status = "disabled";
};
@@ -382,6 +424,9 @@
interrupts = <GIC_SPI 93 IRQ_TYPE_LEVEL_LOW>;
clocks = <&baud_clk>, <&sys_clk>;
clock-names = "baud", "bus";
+ dmas = <&apdma 4
+ &apdma 5>;
+ dma-names = "tx", "rx";
status = "disabled";
};
@@ -392,6 +437,9 @@
interrupts = <GIC_SPI 94 IRQ_TYPE_LEVEL_LOW>;
clocks = <&baud_clk>, <&sys_clk>;
clock-names = "baud", "bus";
+ dmas = <&apdma 6
+ &apdma 7>;
+ dma-names = "tx", "rx";
status = "disabled";
};
@@ -402,6 +450,9 @@
interrupts = <GIC_SPI 126 IRQ_TYPE_LEVEL_LOW>;
clocks = <&baud_clk>, <&sys_clk>;
clock-names = "baud", "bus";
+ dmas = <&apdma 8
+ &apdma 9>;
+ dma-names = "tx", "rx";
status = "disabled";
};
--
1.7.9.5
On Fri, 18 Jan 2019 11:10:16 +0800, Long Cheng wrote:
> The filename matches mtk-uart-apdma.c.
> So using "mtk-uart-apdma.txt" should be better.
>
> Signed-off-by: Long Cheng <[email protected]>
> ---
> .../devicetree/bindings/dma/8250_mtk_dma.txt | 33 --------------------
> .../devicetree/bindings/dma/mtk-uart-apdma.txt | 33 ++++++++++++++++++++
> 2 files changed, 33 insertions(+), 33 deletions(-)
> delete mode 100644 Documentation/devicetree/bindings/dma/8250_mtk_dma.txt
> create mode 100644 Documentation/devicetree/bindings/dma/mtk-uart-apdma.txt
>
Reviewed-by: Rob Herring <[email protected]>
On Fri, 2019-01-18 at 11:10 +0800, Long Cheng wrote:
Hi Vinod Koul,
Just a gentle ping!
thanks.
> In DMA engine framework, add 8250 uart dma to support MediaTek uart.
> If MediaTek uart enabled(SERIAL_8250_MT6577), and want to improve
> the performance, can enable the function.
>
> Signed-off-by: Long Cheng <[email protected]>
> ---
> drivers/dma/mediatek/Kconfig | 11 +
> drivers/dma/mediatek/Makefile | 1 +
> drivers/dma/mediatek/mtk-uart-apdma.c | 669 +++++++++++++++++++++++++++++++++
> 3 files changed, 681 insertions(+)
> create mode 100644 drivers/dma/mediatek/mtk-uart-apdma.c
>
> diff --git a/drivers/dma/mediatek/Kconfig b/drivers/dma/mediatek/Kconfig
> index 680fc05..ac49eb6 100644
> --- a/drivers/dma/mediatek/Kconfig
> +++ b/drivers/dma/mediatek/Kconfig
> @@ -24,3 +24,14 @@ config MTK_CQDMA
>
> This controller provides the channels which is dedicated to
> memory-to-memory transfer to offload from CPU.
> +
> +config MTK_UART_APDMA
> + tristate "MediaTek SoCs APDMA support for UART"
> + depends on OF && SERIAL_8250_MT6577
> + select DMA_ENGINE
> + select DMA_VIRTUAL_CHANNELS
> + help
> + Support for the UART DMA engine found on MediaTek MTK SoCs.
> + When SERIAL_8250_MT6577 is enabled, and if you want to use DMA,
> + you can enable the config. The DMA engine can only be used
> + with MediaTek SoCs.
> diff --git a/drivers/dma/mediatek/Makefile b/drivers/dma/mediatek/Makefile
> index 41bb381..61a6d29 100644
> --- a/drivers/dma/mediatek/Makefile
> +++ b/drivers/dma/mediatek/Makefile
> @@ -1,2 +1,3 @@
> +obj-$(CONFIG_MTK_UART_APDMA) += mtk-uart-apdma.o
> obj-$(CONFIG_MTK_HSDMA) += mtk-hsdma.o
> obj-$(CONFIG_MTK_CQDMA) += mtk-cqdma.o
> diff --git a/drivers/dma/mediatek/mtk-uart-apdma.c b/drivers/dma/mediatek/mtk-uart-apdma.c
> new file mode 100644
> index 0000000..427db69
> --- /dev/null
> +++ b/drivers/dma/mediatek/mtk-uart-apdma.c
> @@ -0,0 +1,669 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * MediaTek Uart APDMA driver.
> + *
> + * Copyright (c) 2018 MediaTek Inc.
> + * Author: Long Cheng <[email protected]>
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/dmaengine.h>
> +#include <linux/dma-mapping.h>
> +#include <linux/err.h>
> +#include <linux/init.h>
> +#include <linux/interrupt.h>
> +#include <linux/iopoll.h>
> +#include <linux/kernel.h>
> +#include <linux/list.h>
> +#include <linux/module.h>
> +#include <linux/of_device.h>
> +#include <linux/of_dma.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/slab.h>
> +#include <linux/spinlock.h>
> +
> +#include "../virt-dma.h"
> +
> +/* The default number of virtual channel */
> +#define MTK_UART_APDMA_NR_VCHANS 8
> +
> +#define VFF_EN_B BIT(0)
> +#define VFF_STOP_B BIT(0)
> +#define VFF_FLUSH_B BIT(0)
> +#define VFF_4G_SUPPORT_B BIT(0)
> +#define VFF_RX_INT_EN0_B BIT(0) /* rx valid size >= vff thre */
> +#define VFF_RX_INT_EN1_B BIT(1)
> +#define VFF_TX_INT_EN_B BIT(0) /* tx left size >= vff thre */
> +#define VFF_WARM_RST_B BIT(0)
> +#define VFF_RX_INT_CLR_B (BIT(0) | BIT(1))
> +#define VFF_TX_INT_CLR_B 0
> +#define VFF_STOP_CLR_B 0
> +#define VFF_INT_EN_CLR_B 0
> +#define VFF_4G_SUPPORT_CLR_B 0
> +
> +/* interrupt trigger level for tx */
> +#define VFF_TX_THRE(n) ((n) * 7 / 8)
> +/* interrupt trigger level for rx */
> +#define VFF_RX_THRE(n) ((n) * 3 / 4)
> +
> +#define VFF_RING_SIZE 0xffffU
> +/* invert this bit when wrap ring head again */
> +#define VFF_RING_WRAP 0x10000U
> +
> +#define VFF_INT_FLAG 0x00
> +#define VFF_INT_EN 0x04
> +#define VFF_EN 0x08
> +#define VFF_RST 0x0c
> +#define VFF_STOP 0x10
> +#define VFF_FLUSH 0x14
> +#define VFF_ADDR 0x1c
> +#define VFF_LEN 0x24
> +#define VFF_THRE 0x28
> +#define VFF_WPT 0x2c
> +#define VFF_RPT 0x30
> +/* TX: the buffer size HW can read. RX: the buffer size SW can read. */
> +#define VFF_VALID_SIZE 0x3c
> +/* TX: the buffer size SW can write. RX: the buffer size HW can write. */
> +#define VFF_LEFT_SIZE 0x40
> +#define VFF_DEBUG_STATUS 0x50
> +#define VFF_4G_SUPPORT 0x54
> +
> +struct mtk_uart_apdmadev {
> + struct dma_device ddev;
> + struct clk *clk;
> + bool support_33bits;
> + unsigned int dma_requests;
> + unsigned int *dma_irq;
> +};
> +
> +struct mtk_uart_apdma_desc {
> + struct virt_dma_desc vd;
> +
> + unsigned int avail_len;
> +};
> +
> +struct mtk_chan {
> + struct virt_dma_chan vc;
> + struct dma_slave_config cfg;
> + void __iomem *base;
> + struct mtk_uart_apdma_desc *desc;
> +
> + enum dma_transfer_direction dir;
> +
> + bool requested;
> +
> + unsigned int rx_status;
> +};
> +
> +static inline struct mtk_uart_apdmadev *
> +to_mtk_uart_apdma_dev(struct dma_device *d)
> +{
> + return container_of(d, struct mtk_uart_apdmadev, ddev);
> +}
> +
> +static inline struct mtk_chan *to_mtk_uart_apdma_chan(struct dma_chan *c)
> +{
> + return container_of(c, struct mtk_chan, vc.chan);
> +}
> +
> +static inline struct mtk_uart_apdma_desc *to_mtk_uart_apdma_desc
> + (struct dma_async_tx_descriptor *t)
> +{
> + return container_of(t, struct mtk_uart_apdma_desc, vd.tx);
> +}
> +
> +static void mtk_uart_apdma_write(struct mtk_chan *c,
> + unsigned int reg, unsigned int val)
> +{
> + writel(val, c->base + reg);
> +}
> +
> +static unsigned int mtk_uart_apdma_read(struct mtk_chan *c, unsigned int reg)
> +{
> + return readl(c->base + reg);
> +}
> +
> +static void mtk_uart_apdma_desc_free(struct virt_dma_desc *vd)
> +{
> + struct dma_chan *chan = vd->tx.chan;
> + struct mtk_chan *c = to_mtk_uart_apdma_chan(chan);
> +
> + kfree(c->desc);
> +}
> +
> +static void mtk_uart_apdma_start_tx(struct mtk_chan *c)
> +{
> + unsigned int len, send, left, wpt, d_wpt, tmp;
> + int ret;
> +
> + left = mtk_uart_apdma_read(c, VFF_LEFT_SIZE);
> + if (!left) {
> + mtk_uart_apdma_write(c, VFF_INT_EN, VFF_TX_INT_EN_B);
> + return;
> + }
> +
> + /* Wait 1sec for flush, can't sleep */
> + ret = readx_poll_timeout(readl, c->base + VFF_FLUSH, tmp,
> + tmp != VFF_FLUSH_B, 0, 1000000);
> + if (ret)
> + dev_warn(c->vc.chan.device->dev, "tx: fail, debug=0x%x\n",
> + mtk_uart_apdma_read(c, VFF_DEBUG_STATUS));
> +
> + send = min_t(unsigned int, left, c->desc->avail_len);
> + wpt = mtk_uart_apdma_read(c, VFF_WPT);
> + len = mtk_uart_apdma_read(c, VFF_LEN);
> +
> + d_wpt = wpt + send;
> + if ((d_wpt & VFF_RING_SIZE) >= len) {
> + d_wpt = d_wpt - len;
> + d_wpt = d_wpt ^ VFF_RING_WRAP;
> + }
> + mtk_uart_apdma_write(c, VFF_WPT, d_wpt);
> +
> + c->desc->avail_len -= send;
> +
> + mtk_uart_apdma_write(c, VFF_INT_EN, VFF_TX_INT_EN_B);
> + if (mtk_uart_apdma_read(c, VFF_FLUSH) == 0U)
> + mtk_uart_apdma_write(c, VFF_FLUSH, VFF_FLUSH_B);
> +}
> +
> +static void mtk_uart_apdma_start_rx(struct mtk_chan *c)
> +{
> + struct mtk_uart_apdma_desc *d = c->desc;
> + unsigned int len, wg, rg;
> + int cnt;
> +
> + if ((mtk_uart_apdma_read(c, VFF_VALID_SIZE) == 0U) ||
> + !d || !vchan_next_desc(&c->vc))
> + return;
> +
> + len = mtk_uart_apdma_read(c, VFF_LEN);
> + rg = mtk_uart_apdma_read(c, VFF_RPT);
> + wg = mtk_uart_apdma_read(c, VFF_WPT);
> + cnt = (wg & VFF_RING_SIZE) - (rg & VFF_RING_SIZE);
> + /*
> + * The buffer is ring buffer. If wrap bit different,
> + * represents the start of the next cycle for WPT
> + */
> + if ((rg ^ wg) & VFF_RING_WRAP)
> + cnt += len;
> +
> + c->rx_status = cnt;
> + mtk_uart_apdma_write(c, VFF_RPT, wg);
> +
> + list_del(&d->vd.node);
> + vchan_cookie_complete(&d->vd);
> +}
> +
> +static irqreturn_t mtk_uart_apdma_irq_handler(int irq, void *dev_id)
> +{
> + struct dma_chan *chan = (struct dma_chan *)dev_id;
> + struct mtk_chan *c = to_mtk_uart_apdma_chan(chan);
> + struct mtk_uart_apdma_desc *d;
> + unsigned long flags;
> +
> + spin_lock_irqsave(&c->vc.lock, flags);
> + if (c->dir == DMA_DEV_TO_MEM) {
> + mtk_uart_apdma_write(c, VFF_INT_FLAG, VFF_RX_INT_CLR_B);
> + mtk_uart_apdma_start_rx(c);
> + } else if (c->dir == DMA_MEM_TO_DEV) {
> + d = c->desc;
> +
> + mtk_uart_apdma_write(c, VFF_INT_FLAG, VFF_TX_INT_CLR_B);
> +
> + if (d->avail_len != 0U) {
> + mtk_uart_apdma_start_tx(c);
> + } else {
> + list_del(&d->vd.node);
> + vchan_cookie_complete(&d->vd);
> + }
> + }
> + spin_unlock_irqrestore(&c->vc.lock, flags);
> +
> + return IRQ_HANDLED;
> +}
> +
> +static int mtk_uart_apdma_alloc_chan_resources(struct dma_chan *chan)
> +{
> + struct mtk_uart_apdmadev *mtkd = to_mtk_uart_apdma_dev(chan->device);
> + struct mtk_chan *c = to_mtk_uart_apdma_chan(chan);
> + unsigned int tmp;
> + int ret;
> +
> + pm_runtime_get_sync(mtkd->ddev.dev);
> +
> + mtk_uart_apdma_write(c, VFF_ADDR, 0);
> + mtk_uart_apdma_write(c, VFF_THRE, 0);
> + mtk_uart_apdma_write(c, VFF_LEN, 0);
> + mtk_uart_apdma_write(c, VFF_RST, VFF_WARM_RST_B);
> +
> + ret = readx_poll_timeout(readl, c->base + VFF_EN, tmp, !tmp, 10, 100);
> + if (ret) {
> + dev_err(chan->device->dev, "dma reset: fail, timeout\n");
> + return ret;
> + }
> +
> + if (!c->requested) {
> + c->requested = true;
> + ret = request_irq(mtkd->dma_irq[chan->chan_id],
> + mtk_uart_apdma_irq_handler, IRQF_TRIGGER_NONE,
> + KBUILD_MODNAME, chan);
> + if (ret < 0) {
> + dev_err(chan->device->dev, "Can't request dma IRQ\n");
> + return -EINVAL;
> + }
> + }
> +
> + if (mtkd->support_33bits)
> + mtk_uart_apdma_write(c, VFF_4G_SUPPORT, VFF_4G_SUPPORT_CLR_B);
> +
> + return ret;
> +}
> +
> +static void mtk_uart_apdma_free_chan_resources(struct dma_chan *chan)
> +{
> + struct mtk_uart_apdmadev *mtkd = to_mtk_uart_apdma_dev(chan->device);
> + struct mtk_chan *c = to_mtk_uart_apdma_chan(chan);
> +
> + if (c->requested) {
> + c->requested = false;
> + free_irq(mtkd->dma_irq[chan->chan_id], chan);
> + }
> +
> + tasklet_kill(&c->vc.task);
> +
> + vchan_free_chan_resources(&c->vc);
> +
> + pm_runtime_put_sync(mtkd->ddev.dev);
> +}
> +
> +static enum dma_status mtk_uart_apdma_tx_status(struct dma_chan *chan,
> + dma_cookie_t cookie,
> + struct dma_tx_state *txstate)
> +{
> + struct mtk_chan *c = to_mtk_uart_apdma_chan(chan);
> + enum dma_status ret;
> + unsigned long flags;
> +
> + if (!txstate)
> + return DMA_ERROR;
> +
> + ret = dma_cookie_status(chan, cookie, txstate);
> + spin_lock_irqsave(&c->vc.lock, flags);
> + if (ret == DMA_IN_PROGRESS) {
> + c->rx_status = mtk_uart_apdma_read(c, VFF_RPT) & VFF_RING_SIZE;
> + dma_set_residue(txstate, c->rx_status);
> + } else if (ret == DMA_COMPLETE && c->dir == DMA_DEV_TO_MEM) {
> + dma_set_residue(txstate, c->rx_status);
> + } else {
> + dma_set_residue(txstate, 0);
> + }
> + spin_unlock_irqrestore(&c->vc.lock, flags);
> +
> + return ret;
> +}
> +
> +static void mtk_uart_apdma_config_write(struct dma_chan *chan,
> + struct dma_slave_config *cfg,
> + enum dma_transfer_direction dir)
> +{
> + struct mtk_chan *c = to_mtk_uart_apdma_chan(chan);
> + struct mtk_uart_apdmadev *mtkd =
> + to_mtk_uart_apdma_dev(c->vc.chan.device);
> + unsigned int tmp;
> +
> + if (mtk_uart_apdma_read(c, VFF_EN) == VFF_EN_B)
> + return;
> +
> + c->dir = dir;
> +
> + if (dir == DMA_DEV_TO_MEM) {
> + tmp = cfg->src_addr_width * 1024;
> +
> + mtk_uart_apdma_write(c, VFF_ADDR, cfg->src_addr);
> + mtk_uart_apdma_write(c, VFF_LEN, tmp);
> + mtk_uart_apdma_write(c, VFF_THRE, VFF_RX_THRE(tmp));
> + mtk_uart_apdma_write(c, VFF_INT_EN,
> + VFF_RX_INT_EN0_B | VFF_RX_INT_EN1_B);
> + mtk_uart_apdma_write(c, VFF_RPT, 0);
> + mtk_uart_apdma_write(c, VFF_INT_FLAG, VFF_RX_INT_CLR_B);
> + } else if (dir == DMA_MEM_TO_DEV) {
> + tmp = cfg->dst_addr_width * 1024;
> +
> + mtk_uart_apdma_write(c, VFF_ADDR, cfg->dst_addr);
> + mtk_uart_apdma_write(c, VFF_LEN, tmp);
> + mtk_uart_apdma_write(c, VFF_THRE, VFF_TX_THRE(tmp));
> + mtk_uart_apdma_write(c, VFF_WPT, 0);
> + mtk_uart_apdma_write(c, VFF_INT_FLAG, VFF_TX_INT_CLR_B);
> + }
> +
> + mtk_uart_apdma_write(c, VFF_EN, VFF_EN_B);
> +
> + if (mtkd->support_33bits)
> + mtk_uart_apdma_write(c, VFF_4G_SUPPORT, VFF_4G_SUPPORT_B);
> +
> + if (mtk_uart_apdma_read(c, VFF_EN) != VFF_EN_B)
> + dev_err(chan->device->dev, "dir[%d] fail\n", dir);
> +}
> +
> +/*
> + * dmaengine_prep_slave_single will call the function. and sglen is 1.
> + * 8250 uart using one ring buffer, and deal with one sg.
> + */
> +static struct dma_async_tx_descriptor *mtk_uart_apdma_prep_slave_sg
> + (struct dma_chan *chan, struct scatterlist *sgl,
> + unsigned int sglen, enum dma_transfer_direction dir,
> + unsigned long tx_flags, void *context)
> +{
> + struct mtk_chan *c = to_mtk_uart_apdma_chan(chan);
> + struct mtk_uart_apdma_desc *d;
> +
> + if (!is_slave_direction(dir))
> + return NULL;
> +
> + mtk_uart_apdma_config_write(chan, &c->cfg, dir);
> +
> + /* Now allocate and setup the descriptor */
> + d = kzalloc(sizeof(*d), GFP_ATOMIC);
> + if (!d)
> + return NULL;
> +
> + /* sglen is 1 */
> + d->avail_len = sg_dma_len(sgl);
> +
> + return vchan_tx_prep(&c->vc, &d->vd, tx_flags);
> +}
> +
> +static void mtk_uart_apdma_issue_pending(struct dma_chan *chan)
> +{
> + struct mtk_chan *c = to_mtk_uart_apdma_chan(chan);
> + struct virt_dma_desc *vd;
> + unsigned long flags;
> +
> + spin_lock_irqsave(&c->vc.lock, flags);
> + if (vchan_issue_pending(&c->vc)) {
> + vd = vchan_next_desc(&c->vc);
> + c->desc = to_mtk_uart_apdma_desc(&vd->tx);
> + }
> +
> + if (c->dir == DMA_DEV_TO_MEM)
> + mtk_uart_apdma_start_rx(c);
> + else if (c->dir == DMA_MEM_TO_DEV)
> + mtk_uart_apdma_start_tx(c);
> +
> + spin_unlock_irqrestore(&c->vc.lock, flags);
> +}
> +
> +static int mtk_uart_apdma_slave_config(struct dma_chan *chan,
> + struct dma_slave_config *config)
> +{
> + struct mtk_chan *c = to_mtk_uart_apdma_chan(chan);
> +
> + memcpy(&c->cfg, config, sizeof(*config));
> +
> + return 0;
> +}
> +
> +static int mtk_uart_apdma_terminate_all(struct dma_chan *chan)
> +{
> + struct mtk_chan *c = to_mtk_uart_apdma_chan(chan);
> + unsigned long flags;
> + unsigned int tmp;
> + int ret;
> +
> + spin_lock_irqsave(&c->vc.lock, flags);
> +
> + mtk_uart_apdma_write(c, VFF_FLUSH, VFF_FLUSH_B);
> + /* Wait 1sec for flush, can't sleep */
> + ret = readx_poll_timeout(readl, c->base + VFF_FLUSH, tmp,
> + tmp != VFF_FLUSH_B, 0, 1000000);
> + if (ret)
> + dev_err(c->vc.chan.device->dev, "flush: fail, debug=0x%x\n",
> + mtk_uart_apdma_read(c, VFF_DEBUG_STATUS));
> +
> + /* set stop as 1 -> wait until en is 0 -> set stop as 0 */
> + mtk_uart_apdma_write(c, VFF_STOP, VFF_STOP_B);
> + ret = readx_poll_timeout(readl, c->base + VFF_EN, tmp, !tmp, 10, 100);
> + if (ret)
> + dev_err(c->vc.chan.device->dev, "stop: fail, debug=0x%x\n",
> + mtk_uart_apdma_read(c, VFF_DEBUG_STATUS));
> +
> + mtk_uart_apdma_write(c, VFF_STOP, VFF_STOP_CLR_B);
> + mtk_uart_apdma_write(c, VFF_INT_EN, VFF_INT_EN_CLR_B);
> +
> + if (c->dir == DMA_DEV_TO_MEM)
> + mtk_uart_apdma_write(c, VFF_INT_FLAG, VFF_RX_INT_CLR_B);
> + else if (c->dir == DMA_MEM_TO_DEV)
> + mtk_uart_apdma_write(c, VFF_INT_FLAG, VFF_TX_INT_CLR_B);
> +
> + spin_unlock_irqrestore(&c->vc.lock, flags);
> +
> + return 0;
> +}
> +
> +static int mtk_uart_apdma_device_pause(struct dma_chan *chan)
> +{
> + /* just for check caps pass */
> + return 0;
> +}
> +
> +static void mtk_uart_apdma_free(struct mtk_uart_apdmadev *mtkd)
> +{
> + while (!list_empty(&mtkd->ddev.channels)) {
> + struct mtk_chan *c = list_first_entry(&mtkd->ddev.channels,
> + struct mtk_chan, vc.chan.device_node);
> +
> + list_del(&c->vc.chan.device_node);
> + tasklet_kill(&c->vc.task);
> + }
> +}
> +
> +static const struct of_device_id mtk_uart_apdma_match[] = {
> + { .compatible = "mediatek,mt6577-uart-dma", },
> + { /* sentinel */ },
> +};
> +MODULE_DEVICE_TABLE(of, mtk_uart_apdma_match);
> +
> +static int mtk_uart_apdma_probe(struct platform_device *pdev)
> +{
> + struct device_node *np = pdev->dev.of_node;
> + struct mtk_uart_apdmadev *mtkd;
> + struct resource *res;
> + struct mtk_chan *c;
> + int bit_mask = 32, rc;
> + unsigned int i;
> +
> + mtkd = devm_kzalloc(&pdev->dev, sizeof(*mtkd), GFP_KERNEL);
> + if (!mtkd)
> + return -ENOMEM;
> +
> + mtkd->clk = devm_clk_get(&pdev->dev, NULL);
> + if (IS_ERR(mtkd->clk)) {
> + dev_err(&pdev->dev, "No clock specified\n");
> + rc = PTR_ERR(mtkd->clk);
> + return rc;
> + }
> +
> + if (of_property_read_bool(np, "dma-33bits"))
> + mtkd->support_33bits = true;
> +
> + if (mtkd->support_33bits)
> + bit_mask = 33;
> +
> + rc = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(bit_mask));
> + if (rc)
> + return rc;
> +
> + dma_cap_set(DMA_SLAVE, mtkd->ddev.cap_mask);
> + mtkd->ddev.device_alloc_chan_resources =
> + mtk_uart_apdma_alloc_chan_resources;
> + mtkd->ddev.device_free_chan_resources =
> + mtk_uart_apdma_free_chan_resources;
> + mtkd->ddev.device_tx_status = mtk_uart_apdma_tx_status;
> + mtkd->ddev.device_issue_pending = mtk_uart_apdma_issue_pending;
> + mtkd->ddev.device_prep_slave_sg = mtk_uart_apdma_prep_slave_sg;
> + mtkd->ddev.device_config = mtk_uart_apdma_slave_config;
> + mtkd->ddev.device_pause = mtk_uart_apdma_device_pause;
> + mtkd->ddev.device_terminate_all = mtk_uart_apdma_terminate_all;
> + mtkd->ddev.src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE);
> + mtkd->ddev.dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE);
> + mtkd->ddev.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
> + mtkd->ddev.residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT;
> + mtkd->ddev.dev = &pdev->dev;
> + INIT_LIST_HEAD(&mtkd->ddev.channels);
> +
> + mtkd->dma_requests = MTK_UART_APDMA_NR_VCHANS;
> + if (of_property_read_u32(np, "dma-requests", &mtkd->dma_requests)) {
> + dev_info(&pdev->dev,
> + "Using %u as missing dma-requests property\n",
> + MTK_UART_APDMA_NR_VCHANS);
> + }
> +
> + mtkd->dma_irq = devm_kcalloc(&pdev->dev, mtkd->dma_requests,
> + sizeof(*mtkd->dma_irq), GFP_KERNEL);
> + if (!mtkd->dma_irq)
> + return -ENOMEM;
> +
> + for (i = 0; i < mtkd->dma_requests; i++) {
> + c = devm_kzalloc(mtkd->ddev.dev, sizeof(*c), GFP_KERNEL);
> + if (!c) {
> + rc = -ENODEV;
> + goto err_no_dma;
> + }
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, i);
> + if (!res) {
> + rc = -ENODEV;
> + goto err_no_dma;
> + }
> +
> + c->base = devm_ioremap_resource(&pdev->dev, res);
> + if (IS_ERR(c->base)) {
> + rc = PTR_ERR(c->base);
> + goto err_no_dma;
> + }
> + c->requested = false;
> + c->vc.desc_free = mtk_uart_apdma_desc_free;
> + vchan_init(&c->vc, &mtkd->ddev);
> +
> + mtkd->dma_irq[i] = platform_get_irq(pdev, i);
> + if ((int)mtkd->dma_irq[i] < 0) {
> + dev_err(&pdev->dev, "failed to get IRQ[%d]\n", i);
> + rc = -EINVAL;
> + goto err_no_dma;
> + }
> + }
> +
> + pm_runtime_enable(&pdev->dev);
> + pm_runtime_set_active(&pdev->dev);
> +
> + rc = dma_async_device_register(&mtkd->ddev);
> + if (rc)
> + goto rpm_disable;
> +
> + platform_set_drvdata(pdev, mtkd);
> +
> + /* Device-tree DMA controller registration */
> + rc = of_dma_controller_register(np, of_dma_xlate_by_chan_id, mtkd);
> + if (rc)
> + goto dma_remove;
> +
> + return rc;
> +
> +dma_remove:
> + dma_async_device_unregister(&mtkd->ddev);
> +rpm_disable:
> + pm_runtime_disable(&pdev->dev);
> +err_no_dma:
> + mtk_uart_apdma_free(mtkd);
> + return rc;
> +}
> +
> +static int mtk_uart_apdma_remove(struct platform_device *pdev)
> +{
> + struct mtk_uart_apdmadev *mtkd = platform_get_drvdata(pdev);
> +
> + if (pdev->dev.of_node)
> + of_dma_controller_free(pdev->dev.of_node);
> +
> + pm_runtime_disable(&pdev->dev);
> + pm_runtime_put_noidle(&pdev->dev);
> +
> + dma_async_device_unregister(&mtkd->ddev);
> + mtk_uart_apdma_free(mtkd);
> +
> + return 0;
> +}
> +
> +#ifdef CONFIG_PM_SLEEP
> +static int mtk_uart_apdma_suspend(struct device *dev)
> +{
> + struct mtk_uart_apdmadev *mtkd = dev_get_drvdata(dev);
> +
> + if (!pm_runtime_suspended(dev))
> + clk_disable_unprepare(mtkd->clk);
> +
> + return 0;
> +}
> +
> +static int mtk_uart_apdma_resume(struct device *dev)
> +{
> + int ret;
> + struct mtk_uart_apdmadev *mtkd = dev_get_drvdata(dev);
> +
> + if (!pm_runtime_suspended(dev)) {
> + ret = clk_prepare_enable(mtkd->clk);
> + if (ret)
> + return ret;
> + }
> +
> + return 0;
> +}
> +#endif /* CONFIG_PM_SLEEP */
> +
> +#ifdef CONFIG_PM
> +static int mtk_uart_apdma_runtime_suspend(struct device *dev)
> +{
> + struct mtk_uart_apdmadev *mtkd = dev_get_drvdata(dev);
> +
> + clk_disable_unprepare(mtkd->clk);
> +
> + return 0;
> +}
> +
> +static int mtk_uart_apdma_runtime_resume(struct device *dev)
> +{
> + int ret;
> + struct mtk_uart_apdmadev *mtkd = dev_get_drvdata(dev);
> +
> + ret = clk_prepare_enable(mtkd->clk);
> + if (ret)
> + return ret;
> +
> + return 0;
> +}
> +#endif /* CONFIG_PM */
> +
> +static const struct dev_pm_ops mtk_uart_apdma_pm_ops = {
> + SET_SYSTEM_SLEEP_PM_OPS(mtk_uart_apdma_suspend, mtk_uart_apdma_resume)
> + SET_RUNTIME_PM_OPS(mtk_uart_apdma_runtime_suspend,
> + mtk_uart_apdma_runtime_resume, NULL)
> +};
> +
> +static struct platform_driver mtk_uart_apdma_driver = {
> + .probe = mtk_uart_apdma_probe,
> + .remove = mtk_uart_apdma_remove,
> + .driver = {
> + .name = KBUILD_MODNAME,
> + .pm = &mtk_uart_apdma_pm_ops,
> + .of_match_table = of_match_ptr(mtk_uart_apdma_match),
> + },
> +};
> +
> +module_platform_driver(mtk_uart_apdma_driver);
> +
> +MODULE_DESCRIPTION("MediaTek UART APDMA Controller Driver");
> +MODULE_AUTHOR("Long Cheng <[email protected]>");
> +MODULE_LICENSE("GPL v2");
> +
In DMA engine framework, add 8250 uart dma to support MediaTek uart.
If MediaTek uart enabled(SERIAL_8250_MT6577), and want to improve
the performance, can enable the function.
Signed-off-by: Long Cheng <[email protected]>
---
drivers/dma/mediatek/Kconfig | 11 +
drivers/dma/mediatek/Makefile | 1 +
drivers/dma/mediatek/mtk-uart-apdma.c | 669 +++++++++++++++++++++++++++++++++
3 files changed, 681 insertions(+)
create mode 100644 drivers/dma/mediatek/mtk-uart-apdma.c
diff --git a/drivers/dma/mediatek/Kconfig b/drivers/dma/mediatek/Kconfig
index 680fc05..ac49eb6 100644
--- a/drivers/dma/mediatek/Kconfig
+++ b/drivers/dma/mediatek/Kconfig
@@ -24,3 +24,14 @@ config MTK_CQDMA
This controller provides the channels which is dedicated to
memory-to-memory transfer to offload from CPU.
+
+config MTK_UART_APDMA
+ tristate "MediaTek SoCs APDMA support for UART"
+ depends on OF && SERIAL_8250_MT6577
+ select DMA_ENGINE
+ select DMA_VIRTUAL_CHANNELS
+ help
+ Support for the UART DMA engine found on MediaTek MTK SoCs.
+ When SERIAL_8250_MT6577 is enabled, and if you want to use DMA,
+ you can enable the config. The DMA engine can only be used
+ with MediaTek SoCs.
diff --git a/drivers/dma/mediatek/Makefile b/drivers/dma/mediatek/Makefile
index 41bb381..61a6d29 100644
--- a/drivers/dma/mediatek/Makefile
+++ b/drivers/dma/mediatek/Makefile
@@ -1,2 +1,3 @@
+obj-$(CONFIG_MTK_UART_APDMA) += mtk-uart-apdma.o
obj-$(CONFIG_MTK_HSDMA) += mtk-hsdma.o
obj-$(CONFIG_MTK_CQDMA) += mtk-cqdma.o
diff --git a/drivers/dma/mediatek/mtk-uart-apdma.c b/drivers/dma/mediatek/mtk-uart-apdma.c
new file mode 100644
index 0000000..427db69
--- /dev/null
+++ b/drivers/dma/mediatek/mtk-uart-apdma.c
@@ -0,0 +1,669 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * MediaTek Uart APDMA driver.
+ *
+ * Copyright (c) 2018 MediaTek Inc.
+ * Author: Long Cheng <[email protected]>
+ */
+
+#include <linux/clk.h>
+#include <linux/dmaengine.h>
+#include <linux/dma-mapping.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/iopoll.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/of_dma.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+
+#include "../virt-dma.h"
+
+/* The default number of virtual channel */
+#define MTK_UART_APDMA_NR_VCHANS 8
+
+#define VFF_EN_B BIT(0)
+#define VFF_STOP_B BIT(0)
+#define VFF_FLUSH_B BIT(0)
+#define VFF_4G_SUPPORT_B BIT(0)
+#define VFF_RX_INT_EN0_B BIT(0) /* rx valid size >= vff thre */
+#define VFF_RX_INT_EN1_B BIT(1)
+#define VFF_TX_INT_EN_B BIT(0) /* tx left size >= vff thre */
+#define VFF_WARM_RST_B BIT(0)
+#define VFF_RX_INT_CLR_B (BIT(0) | BIT(1))
+#define VFF_TX_INT_CLR_B 0
+#define VFF_STOP_CLR_B 0
+#define VFF_INT_EN_CLR_B 0
+#define VFF_4G_SUPPORT_CLR_B 0
+
+/* interrupt trigger level for tx */
+#define VFF_TX_THRE(n) ((n) * 7 / 8)
+/* interrupt trigger level for rx */
+#define VFF_RX_THRE(n) ((n) * 3 / 4)
+
+#define VFF_RING_SIZE 0xffffU
+/* invert this bit when wrap ring head again */
+#define VFF_RING_WRAP 0x10000U
+
+#define VFF_INT_FLAG 0x00
+#define VFF_INT_EN 0x04
+#define VFF_EN 0x08
+#define VFF_RST 0x0c
+#define VFF_STOP 0x10
+#define VFF_FLUSH 0x14
+#define VFF_ADDR 0x1c
+#define VFF_LEN 0x24
+#define VFF_THRE 0x28
+#define VFF_WPT 0x2c
+#define VFF_RPT 0x30
+/* TX: the buffer size HW can read. RX: the buffer size SW can read. */
+#define VFF_VALID_SIZE 0x3c
+/* TX: the buffer size SW can write. RX: the buffer size HW can write. */
+#define VFF_LEFT_SIZE 0x40
+#define VFF_DEBUG_STATUS 0x50
+#define VFF_4G_SUPPORT 0x54
+
+struct mtk_uart_apdmadev {
+ struct dma_device ddev;
+ struct clk *clk;
+ bool support_33bits;
+ unsigned int dma_requests;
+ unsigned int *dma_irq;
+};
+
+struct mtk_uart_apdma_desc {
+ struct virt_dma_desc vd;
+
+ unsigned int avail_len;
+};
+
+struct mtk_chan {
+ struct virt_dma_chan vc;
+ struct dma_slave_config cfg;
+ void __iomem *base;
+ struct mtk_uart_apdma_desc *desc;
+
+ enum dma_transfer_direction dir;
+
+ bool requested;
+
+ unsigned int rx_status;
+};
+
+static inline struct mtk_uart_apdmadev *
+to_mtk_uart_apdma_dev(struct dma_device *d)
+{
+ return container_of(d, struct mtk_uart_apdmadev, ddev);
+}
+
+static inline struct mtk_chan *to_mtk_uart_apdma_chan(struct dma_chan *c)
+{
+ return container_of(c, struct mtk_chan, vc.chan);
+}
+
+static inline struct mtk_uart_apdma_desc *to_mtk_uart_apdma_desc
+ (struct dma_async_tx_descriptor *t)
+{
+ return container_of(t, struct mtk_uart_apdma_desc, vd.tx);
+}
+
+static void mtk_uart_apdma_write(struct mtk_chan *c,
+ unsigned int reg, unsigned int val)
+{
+ writel(val, c->base + reg);
+}
+
+static unsigned int mtk_uart_apdma_read(struct mtk_chan *c, unsigned int reg)
+{
+ return readl(c->base + reg);
+}
+
+static void mtk_uart_apdma_desc_free(struct virt_dma_desc *vd)
+{
+ struct dma_chan *chan = vd->tx.chan;
+ struct mtk_chan *c = to_mtk_uart_apdma_chan(chan);
+
+ kfree(c->desc);
+}
+
+static void mtk_uart_apdma_start_tx(struct mtk_chan *c)
+{
+ unsigned int len, send, left, wpt, d_wpt, tmp;
+ int ret;
+
+ left = mtk_uart_apdma_read(c, VFF_LEFT_SIZE);
+ if (!left) {
+ mtk_uart_apdma_write(c, VFF_INT_EN, VFF_TX_INT_EN_B);
+ return;
+ }
+
+ /* Wait 1sec for flush, can't sleep */
+ ret = readx_poll_timeout(readl, c->base + VFF_FLUSH, tmp,
+ tmp != VFF_FLUSH_B, 0, 1000000);
+ if (ret)
+ dev_warn(c->vc.chan.device->dev, "tx: fail, debug=0x%x\n",
+ mtk_uart_apdma_read(c, VFF_DEBUG_STATUS));
+
+ send = min_t(unsigned int, left, c->desc->avail_len);
+ wpt = mtk_uart_apdma_read(c, VFF_WPT);
+ len = mtk_uart_apdma_read(c, VFF_LEN);
+
+ d_wpt = wpt + send;
+ if ((d_wpt & VFF_RING_SIZE) >= len) {
+ d_wpt = d_wpt - len;
+ d_wpt = d_wpt ^ VFF_RING_WRAP;
+ }
+ mtk_uart_apdma_write(c, VFF_WPT, d_wpt);
+
+ c->desc->avail_len -= send;
+
+ mtk_uart_apdma_write(c, VFF_INT_EN, VFF_TX_INT_EN_B);
+ if (mtk_uart_apdma_read(c, VFF_FLUSH) == 0U)
+ mtk_uart_apdma_write(c, VFF_FLUSH, VFF_FLUSH_B);
+}
+
+static void mtk_uart_apdma_start_rx(struct mtk_chan *c)
+{
+ struct mtk_uart_apdma_desc *d = c->desc;
+ unsigned int len, wg, rg;
+ int cnt;
+
+ if ((mtk_uart_apdma_read(c, VFF_VALID_SIZE) == 0U) ||
+ !d || !vchan_next_desc(&c->vc))
+ return;
+
+ len = mtk_uart_apdma_read(c, VFF_LEN);
+ rg = mtk_uart_apdma_read(c, VFF_RPT);
+ wg = mtk_uart_apdma_read(c, VFF_WPT);
+ cnt = (wg & VFF_RING_SIZE) - (rg & VFF_RING_SIZE);
+ /*
+ * The buffer is ring buffer. If wrap bit different,
+ * represents the start of the next cycle for WPT
+ */
+ if ((rg ^ wg) & VFF_RING_WRAP)
+ cnt += len;
+
+ c->rx_status = cnt;
+ mtk_uart_apdma_write(c, VFF_RPT, wg);
+
+ list_del(&d->vd.node);
+ vchan_cookie_complete(&d->vd);
+}
+
+static irqreturn_t mtk_uart_apdma_irq_handler(int irq, void *dev_id)
+{
+ struct dma_chan *chan = (struct dma_chan *)dev_id;
+ struct mtk_chan *c = to_mtk_uart_apdma_chan(chan);
+ struct mtk_uart_apdma_desc *d;
+ unsigned long flags;
+
+ spin_lock_irqsave(&c->vc.lock, flags);
+ if (c->dir == DMA_DEV_TO_MEM) {
+ mtk_uart_apdma_write(c, VFF_INT_FLAG, VFF_RX_INT_CLR_B);
+ mtk_uart_apdma_start_rx(c);
+ } else if (c->dir == DMA_MEM_TO_DEV) {
+ d = c->desc;
+
+ mtk_uart_apdma_write(c, VFF_INT_FLAG, VFF_TX_INT_CLR_B);
+
+ if (d->avail_len != 0U) {
+ mtk_uart_apdma_start_tx(c);
+ } else {
+ list_del(&d->vd.node);
+ vchan_cookie_complete(&d->vd);
+ }
+ }
+ spin_unlock_irqrestore(&c->vc.lock, flags);
+
+ return IRQ_HANDLED;
+}
+
+static int mtk_uart_apdma_alloc_chan_resources(struct dma_chan *chan)
+{
+ struct mtk_uart_apdmadev *mtkd = to_mtk_uart_apdma_dev(chan->device);
+ struct mtk_chan *c = to_mtk_uart_apdma_chan(chan);
+ unsigned int tmp;
+ int ret;
+
+ pm_runtime_get_sync(mtkd->ddev.dev);
+
+ mtk_uart_apdma_write(c, VFF_ADDR, 0);
+ mtk_uart_apdma_write(c, VFF_THRE, 0);
+ mtk_uart_apdma_write(c, VFF_LEN, 0);
+ mtk_uart_apdma_write(c, VFF_RST, VFF_WARM_RST_B);
+
+ ret = readx_poll_timeout(readl, c->base + VFF_EN, tmp, !tmp, 10, 100);
+ if (ret) {
+ dev_err(chan->device->dev, "dma reset: fail, timeout\n");
+ return ret;
+ }
+
+ if (!c->requested) {
+ c->requested = true;
+ ret = request_irq(mtkd->dma_irq[chan->chan_id],
+ mtk_uart_apdma_irq_handler, IRQF_TRIGGER_NONE,
+ KBUILD_MODNAME, chan);
+ if (ret < 0) {
+ dev_err(chan->device->dev, "Can't request dma IRQ\n");
+ return -EINVAL;
+ }
+ }
+
+ if (mtkd->support_33bits)
+ mtk_uart_apdma_write(c, VFF_4G_SUPPORT, VFF_4G_SUPPORT_CLR_B);
+
+ return ret;
+}
+
+static void mtk_uart_apdma_free_chan_resources(struct dma_chan *chan)
+{
+ struct mtk_uart_apdmadev *mtkd = to_mtk_uart_apdma_dev(chan->device);
+ struct mtk_chan *c = to_mtk_uart_apdma_chan(chan);
+
+ if (c->requested) {
+ c->requested = false;
+ free_irq(mtkd->dma_irq[chan->chan_id], chan);
+ }
+
+ tasklet_kill(&c->vc.task);
+
+ vchan_free_chan_resources(&c->vc);
+
+ pm_runtime_put_sync(mtkd->ddev.dev);
+}
+
+static enum dma_status mtk_uart_apdma_tx_status(struct dma_chan *chan,
+ dma_cookie_t cookie,
+ struct dma_tx_state *txstate)
+{
+ struct mtk_chan *c = to_mtk_uart_apdma_chan(chan);
+ enum dma_status ret;
+ unsigned long flags;
+
+ if (!txstate)
+ return DMA_ERROR;
+
+ ret = dma_cookie_status(chan, cookie, txstate);
+ spin_lock_irqsave(&c->vc.lock, flags);
+ if (ret == DMA_IN_PROGRESS) {
+ c->rx_status = mtk_uart_apdma_read(c, VFF_RPT) & VFF_RING_SIZE;
+ dma_set_residue(txstate, c->rx_status);
+ } else if (ret == DMA_COMPLETE && c->dir == DMA_DEV_TO_MEM) {
+ dma_set_residue(txstate, c->rx_status);
+ } else {
+ dma_set_residue(txstate, 0);
+ }
+ spin_unlock_irqrestore(&c->vc.lock, flags);
+
+ return ret;
+}
+
+static void mtk_uart_apdma_config_write(struct dma_chan *chan,
+ struct dma_slave_config *cfg,
+ enum dma_transfer_direction dir)
+{
+ struct mtk_chan *c = to_mtk_uart_apdma_chan(chan);
+ struct mtk_uart_apdmadev *mtkd =
+ to_mtk_uart_apdma_dev(c->vc.chan.device);
+ unsigned int tmp;
+
+ if (mtk_uart_apdma_read(c, VFF_EN) == VFF_EN_B)
+ return;
+
+ c->dir = dir;
+
+ if (dir == DMA_DEV_TO_MEM) {
+ tmp = cfg->src_addr_width * 1024;
+
+ mtk_uart_apdma_write(c, VFF_ADDR, cfg->src_addr);
+ mtk_uart_apdma_write(c, VFF_LEN, tmp);
+ mtk_uart_apdma_write(c, VFF_THRE, VFF_RX_THRE(tmp));
+ mtk_uart_apdma_write(c, VFF_INT_EN,
+ VFF_RX_INT_EN0_B | VFF_RX_INT_EN1_B);
+ mtk_uart_apdma_write(c, VFF_RPT, 0);
+ mtk_uart_apdma_write(c, VFF_INT_FLAG, VFF_RX_INT_CLR_B);
+ } else if (dir == DMA_MEM_TO_DEV) {
+ tmp = cfg->dst_addr_width * 1024;
+
+ mtk_uart_apdma_write(c, VFF_ADDR, cfg->dst_addr);
+ mtk_uart_apdma_write(c, VFF_LEN, tmp);
+ mtk_uart_apdma_write(c, VFF_THRE, VFF_TX_THRE(tmp));
+ mtk_uart_apdma_write(c, VFF_WPT, 0);
+ mtk_uart_apdma_write(c, VFF_INT_FLAG, VFF_TX_INT_CLR_B);
+ }
+
+ mtk_uart_apdma_write(c, VFF_EN, VFF_EN_B);
+
+ if (mtkd->support_33bits)
+ mtk_uart_apdma_write(c, VFF_4G_SUPPORT, VFF_4G_SUPPORT_B);
+
+ if (mtk_uart_apdma_read(c, VFF_EN) != VFF_EN_B)
+ dev_err(chan->device->dev, "dir[%d] fail\n", dir);
+}
+
+/*
+ * dmaengine_prep_slave_single will call the function. and sglen is 1.
+ * 8250 uart using one ring buffer, and deal with one sg.
+ */
+static struct dma_async_tx_descriptor *mtk_uart_apdma_prep_slave_sg
+ (struct dma_chan *chan, struct scatterlist *sgl,
+ unsigned int sglen, enum dma_transfer_direction dir,
+ unsigned long tx_flags, void *context)
+{
+ struct mtk_chan *c = to_mtk_uart_apdma_chan(chan);
+ struct mtk_uart_apdma_desc *d;
+
+ if (!is_slave_direction(dir))
+ return NULL;
+
+ mtk_uart_apdma_config_write(chan, &c->cfg, dir);
+
+ /* Now allocate and setup the descriptor */
+ d = kzalloc(sizeof(*d), GFP_ATOMIC);
+ if (!d)
+ return NULL;
+
+ /* sglen is 1 */
+ d->avail_len = sg_dma_len(sgl);
+
+ return vchan_tx_prep(&c->vc, &d->vd, tx_flags);
+}
+
+static void mtk_uart_apdma_issue_pending(struct dma_chan *chan)
+{
+ struct mtk_chan *c = to_mtk_uart_apdma_chan(chan);
+ struct virt_dma_desc *vd;
+ unsigned long flags;
+
+ spin_lock_irqsave(&c->vc.lock, flags);
+ if (vchan_issue_pending(&c->vc)) {
+ vd = vchan_next_desc(&c->vc);
+ c->desc = to_mtk_uart_apdma_desc(&vd->tx);
+ }
+
+ if (c->dir == DMA_DEV_TO_MEM)
+ mtk_uart_apdma_start_rx(c);
+ else if (c->dir == DMA_MEM_TO_DEV)
+ mtk_uart_apdma_start_tx(c);
+
+ spin_unlock_irqrestore(&c->vc.lock, flags);
+}
+
+static int mtk_uart_apdma_slave_config(struct dma_chan *chan,
+ struct dma_slave_config *config)
+{
+ struct mtk_chan *c = to_mtk_uart_apdma_chan(chan);
+
+ memcpy(&c->cfg, config, sizeof(*config));
+
+ return 0;
+}
+
+static int mtk_uart_apdma_terminate_all(struct dma_chan *chan)
+{
+ struct mtk_chan *c = to_mtk_uart_apdma_chan(chan);
+ unsigned long flags;
+ unsigned int tmp;
+ int ret;
+
+ spin_lock_irqsave(&c->vc.lock, flags);
+
+ mtk_uart_apdma_write(c, VFF_FLUSH, VFF_FLUSH_B);
+ /* Wait 1sec for flush, can't sleep */
+ ret = readx_poll_timeout(readl, c->base + VFF_FLUSH, tmp,
+ tmp != VFF_FLUSH_B, 0, 1000000);
+ if (ret)
+ dev_err(c->vc.chan.device->dev, "flush: fail, debug=0x%x\n",
+ mtk_uart_apdma_read(c, VFF_DEBUG_STATUS));
+
+ /* set stop as 1 -> wait until en is 0 -> set stop as 0 */
+ mtk_uart_apdma_write(c, VFF_STOP, VFF_STOP_B);
+ ret = readx_poll_timeout(readl, c->base + VFF_EN, tmp, !tmp, 10, 100);
+ if (ret)
+ dev_err(c->vc.chan.device->dev, "stop: fail, debug=0x%x\n",
+ mtk_uart_apdma_read(c, VFF_DEBUG_STATUS));
+
+ mtk_uart_apdma_write(c, VFF_STOP, VFF_STOP_CLR_B);
+ mtk_uart_apdma_write(c, VFF_INT_EN, VFF_INT_EN_CLR_B);
+
+ if (c->dir == DMA_DEV_TO_MEM)
+ mtk_uart_apdma_write(c, VFF_INT_FLAG, VFF_RX_INT_CLR_B);
+ else if (c->dir == DMA_MEM_TO_DEV)
+ mtk_uart_apdma_write(c, VFF_INT_FLAG, VFF_TX_INT_CLR_B);
+
+ spin_unlock_irqrestore(&c->vc.lock, flags);
+
+ return 0;
+}
+
+static int mtk_uart_apdma_device_pause(struct dma_chan *chan)
+{
+ /* just for check caps pass */
+ return 0;
+}
+
+static void mtk_uart_apdma_free(struct mtk_uart_apdmadev *mtkd)
+{
+ while (!list_empty(&mtkd->ddev.channels)) {
+ struct mtk_chan *c = list_first_entry(&mtkd->ddev.channels,
+ struct mtk_chan, vc.chan.device_node);
+
+ list_del(&c->vc.chan.device_node);
+ tasklet_kill(&c->vc.task);
+ }
+}
+
+static const struct of_device_id mtk_uart_apdma_match[] = {
+ { .compatible = "mediatek,mt6577-uart-dma", },
+ { /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, mtk_uart_apdma_match);
+
+static int mtk_uart_apdma_probe(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct mtk_uart_apdmadev *mtkd;
+ struct resource *res;
+ struct mtk_chan *c;
+ int bit_mask = 32, rc;
+ unsigned int i;
+
+ mtkd = devm_kzalloc(&pdev->dev, sizeof(*mtkd), GFP_KERNEL);
+ if (!mtkd)
+ return -ENOMEM;
+
+ mtkd->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(mtkd->clk)) {
+ dev_err(&pdev->dev, "No clock specified\n");
+ rc = PTR_ERR(mtkd->clk);
+ return rc;
+ }
+
+ if (of_property_read_bool(np, "dma-33bits"))
+ mtkd->support_33bits = true;
+
+ if (mtkd->support_33bits)
+ bit_mask = 33;
+
+ rc = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(bit_mask));
+ if (rc)
+ return rc;
+
+ dma_cap_set(DMA_SLAVE, mtkd->ddev.cap_mask);
+ mtkd->ddev.device_alloc_chan_resources =
+ mtk_uart_apdma_alloc_chan_resources;
+ mtkd->ddev.device_free_chan_resources =
+ mtk_uart_apdma_free_chan_resources;
+ mtkd->ddev.device_tx_status = mtk_uart_apdma_tx_status;
+ mtkd->ddev.device_issue_pending = mtk_uart_apdma_issue_pending;
+ mtkd->ddev.device_prep_slave_sg = mtk_uart_apdma_prep_slave_sg;
+ mtkd->ddev.device_config = mtk_uart_apdma_slave_config;
+ mtkd->ddev.device_pause = mtk_uart_apdma_device_pause;
+ mtkd->ddev.device_terminate_all = mtk_uart_apdma_terminate_all;
+ mtkd->ddev.src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE);
+ mtkd->ddev.dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE);
+ mtkd->ddev.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
+ mtkd->ddev.residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT;
+ mtkd->ddev.dev = &pdev->dev;
+ INIT_LIST_HEAD(&mtkd->ddev.channels);
+
+ mtkd->dma_requests = MTK_UART_APDMA_NR_VCHANS;
+ if (of_property_read_u32(np, "dma-requests", &mtkd->dma_requests)) {
+ dev_info(&pdev->dev,
+ "Using %u as missing dma-requests property\n",
+ MTK_UART_APDMA_NR_VCHANS);
+ }
+
+ mtkd->dma_irq = devm_kcalloc(&pdev->dev, mtkd->dma_requests,
+ sizeof(*mtkd->dma_irq), GFP_KERNEL);
+ if (!mtkd->dma_irq)
+ return -ENOMEM;
+
+ for (i = 0; i < mtkd->dma_requests; i++) {
+ c = devm_kzalloc(mtkd->ddev.dev, sizeof(*c), GFP_KERNEL);
+ if (!c) {
+ rc = -ENODEV;
+ goto err_no_dma;
+ }
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, i);
+ if (!res) {
+ rc = -ENODEV;
+ goto err_no_dma;
+ }
+
+ c->base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(c->base)) {
+ rc = PTR_ERR(c->base);
+ goto err_no_dma;
+ }
+ c->requested = false;
+ c->vc.desc_free = mtk_uart_apdma_desc_free;
+ vchan_init(&c->vc, &mtkd->ddev);
+
+ mtkd->dma_irq[i] = platform_get_irq(pdev, i);
+ if ((int)mtkd->dma_irq[i] < 0) {
+ dev_err(&pdev->dev, "failed to get IRQ[%d]\n", i);
+ rc = -EINVAL;
+ goto err_no_dma;
+ }
+ }
+
+ pm_runtime_enable(&pdev->dev);
+ pm_runtime_set_active(&pdev->dev);
+
+ rc = dma_async_device_register(&mtkd->ddev);
+ if (rc)
+ goto rpm_disable;
+
+ platform_set_drvdata(pdev, mtkd);
+
+ /* Device-tree DMA controller registration */
+ rc = of_dma_controller_register(np, of_dma_xlate_by_chan_id, mtkd);
+ if (rc)
+ goto dma_remove;
+
+ return rc;
+
+dma_remove:
+ dma_async_device_unregister(&mtkd->ddev);
+rpm_disable:
+ pm_runtime_disable(&pdev->dev);
+err_no_dma:
+ mtk_uart_apdma_free(mtkd);
+ return rc;
+}
+
+static int mtk_uart_apdma_remove(struct platform_device *pdev)
+{
+ struct mtk_uart_apdmadev *mtkd = platform_get_drvdata(pdev);
+
+ if (pdev->dev.of_node)
+ of_dma_controller_free(pdev->dev.of_node);
+
+ pm_runtime_disable(&pdev->dev);
+ pm_runtime_put_noidle(&pdev->dev);
+
+ dma_async_device_unregister(&mtkd->ddev);
+ mtk_uart_apdma_free(mtkd);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int mtk_uart_apdma_suspend(struct device *dev)
+{
+ struct mtk_uart_apdmadev *mtkd = dev_get_drvdata(dev);
+
+ if (!pm_runtime_suspended(dev))
+ clk_disable_unprepare(mtkd->clk);
+
+ return 0;
+}
+
+static int mtk_uart_apdma_resume(struct device *dev)
+{
+ int ret;
+ struct mtk_uart_apdmadev *mtkd = dev_get_drvdata(dev);
+
+ if (!pm_runtime_suspended(dev)) {
+ ret = clk_prepare_enable(mtkd->clk);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+#endif /* CONFIG_PM_SLEEP */
+
+#ifdef CONFIG_PM
+static int mtk_uart_apdma_runtime_suspend(struct device *dev)
+{
+ struct mtk_uart_apdmadev *mtkd = dev_get_drvdata(dev);
+
+ clk_disable_unprepare(mtkd->clk);
+
+ return 0;
+}
+
+static int mtk_uart_apdma_runtime_resume(struct device *dev)
+{
+ int ret;
+ struct mtk_uart_apdmadev *mtkd = dev_get_drvdata(dev);
+
+ ret = clk_prepare_enable(mtkd->clk);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+#endif /* CONFIG_PM */
+
+static const struct dev_pm_ops mtk_uart_apdma_pm_ops = {
+ SET_SYSTEM_SLEEP_PM_OPS(mtk_uart_apdma_suspend, mtk_uart_apdma_resume)
+ SET_RUNTIME_PM_OPS(mtk_uart_apdma_runtime_suspend,
+ mtk_uart_apdma_runtime_resume, NULL)
+};
+
+static struct platform_driver mtk_uart_apdma_driver = {
+ .probe = mtk_uart_apdma_probe,
+ .remove = mtk_uart_apdma_remove,
+ .driver = {
+ .name = KBUILD_MODNAME,
+ .pm = &mtk_uart_apdma_pm_ops,
+ .of_match_table = of_match_ptr(mtk_uart_apdma_match),
+ },
+};
+
+module_platform_driver(mtk_uart_apdma_driver);
+
+MODULE_DESCRIPTION("MediaTek UART APDMA Controller Driver");
+MODULE_AUTHOR("Long Cheng <[email protected]>");
+MODULE_LICENSE("GPL v2");
+
--
1.7.9.5
On 18-01-19, 11:10, Long Cheng wrote:
> +static enum dma_status mtk_uart_apdma_tx_status(struct dma_chan *chan,
> + dma_cookie_t cookie,
> + struct dma_tx_state *txstate)
> +{
> + struct mtk_chan *c = to_mtk_uart_apdma_chan(chan);
> + enum dma_status ret;
> + unsigned long flags;
> +
> + if (!txstate)
> + return DMA_ERROR;
Why, it is not a mandatory arg!
> + ret = dma_cookie_status(chan, cookie, txstate);
> + spin_lock_irqsave(&c->vc.lock, flags);
> + if (ret == DMA_IN_PROGRESS) {
> + c->rx_status = mtk_uart_apdma_read(c, VFF_RPT) & VFF_RING_SIZE;
> + dma_set_residue(txstate, c->rx_status);
> + } else if (ret == DMA_COMPLETE && c->dir == DMA_DEV_TO_MEM) {
> + dma_set_residue(txstate, c->rx_status);
what is the point is setting residue to comleted txn, it is zero!
> + } else {
> + dma_set_residue(txstate, 0);
naah that doesnt sound correct!
> +static void mtk_uart_apdma_config_write(struct dma_chan *chan,
> + struct dma_slave_config *cfg,
> + enum dma_transfer_direction dir)
> +{
> + struct mtk_chan *c = to_mtk_uart_apdma_chan(chan);
> + struct mtk_uart_apdmadev *mtkd =
> + to_mtk_uart_apdma_dev(c->vc.chan.device);
> + unsigned int tmp;
> +
> + if (mtk_uart_apdma_read(c, VFF_EN) == VFF_EN_B)
> + return;
> +
> + c->dir = dir;
> +
> + if (dir == DMA_DEV_TO_MEM) {
> + tmp = cfg->src_addr_width * 1024;
why multiply by 1024?
> +static int mtk_uart_apdma_device_pause(struct dma_chan *chan)
> +{
> + /* just for check caps pass */
> + return 0;
> +}
please remove, this is not a mandatory fn
--
~Vinod
On Mon, 2019-02-04 at 12:51 +0530, Vinod Koul wrote:
Hi Vinod sir,
> On 18-01-19, 11:10, Long Cheng wrote:
> > +static enum dma_status mtk_uart_apdma_tx_status(struct dma_chan *chan,
> > + dma_cookie_t cookie,
> > + struct dma_tx_state *txstate)
> > +{
> > + struct mtk_chan *c = to_mtk_uart_apdma_chan(chan);
> > + enum dma_status ret;
> > + unsigned long flags;
> > +
> > + if (!txstate)
> > + return DMA_ERROR;
>
> Why, it is not a mandatory arg!
Next version, I will remove it.
>
> > + ret = dma_cookie_status(chan, cookie, txstate);
> > + spin_lock_irqsave(&c->vc.lock, flags);
> > + if (ret == DMA_IN_PROGRESS) {
> > + c->rx_status = mtk_uart_apdma_read(c, VFF_RPT) & VFF_RING_SIZE;
> > + dma_set_residue(txstate, c->rx_status);
> > + } else if (ret == DMA_COMPLETE && c->dir == DMA_DEV_TO_MEM) {
> > + dma_set_residue(txstate, c->rx_status);
>
> what is the point is setting residue to comleted txn, it is zero!
>
> > + } else {
> > + dma_set_residue(txstate, 0);
>
> naah that doesnt sound correct!
>
Next version, I will modify the function.
> > +static void mtk_uart_apdma_config_write(struct dma_chan *chan,
> > + struct dma_slave_config *cfg,
> > + enum dma_transfer_direction dir)
> > +{
> > + struct mtk_chan *c = to_mtk_uart_apdma_chan(chan);
> > + struct mtk_uart_apdmadev *mtkd =
> > + to_mtk_uart_apdma_dev(c->vc.chan.device);
> > + unsigned int tmp;
> > +
> > + if (mtk_uart_apdma_read(c, VFF_EN) == VFF_EN_B)
> > + return;
> > +
> > + c->dir = dir;
> > +
> > + if (dir == DMA_DEV_TO_MEM) {
> > + tmp = cfg->src_addr_width * 1024;
>
> why multiply by 1024?
>
Next version, I will modify the this, with 'src_port_window_size' &&
'dst_port_window_size'.
> > +static int mtk_uart_apdma_device_pause(struct dma_chan *chan)
> > +{
> > + /* just for check caps pass */
> > + return 0;
> > +}
>
> please remove, this is not a mandatory fn
Can't remove it. Before the mail, i had explained it. in 8250 uart
framework, will check the function..
thanks.
On 18/01/2019 04:10, Long Cheng wrote:
> In DMA engine framework, add 8250 uart dma to support MediaTek uart.
> If MediaTek uart enabled(SERIAL_8250_MT6577), and want to improve
> the performance, can enable the function.
>
> Signed-off-by: Long Cheng <[email protected]>
> ---
> drivers/dma/mediatek/Kconfig | 11 +
> drivers/dma/mediatek/Makefile | 1 +
> drivers/dma/mediatek/mtk-uart-apdma.c | 669 +++++++++++++++++++++++++++++++++
> 3 files changed, 681 insertions(+)
> create mode 100644 drivers/dma/mediatek/mtk-uart-apdma.c
>
[...]
> +
> +static int mtk_uart_apdma_probe(struct platform_device *pdev)
> +{
> + struct device_node *np = pdev->dev.of_node;
> + struct mtk_uart_apdmadev *mtkd;
> + struct resource *res;
> + struct mtk_chan *c;
> + int bit_mask = 32, rc;
> + unsigned int i;
> +
> + mtkd = devm_kzalloc(&pdev->dev, sizeof(*mtkd), GFP_KERNEL);
> + if (!mtkd)
> + return -ENOMEM;
> +
> + mtkd->clk = devm_clk_get(&pdev->dev, NULL);
> + if (IS_ERR(mtkd->clk)) {
> + dev_err(&pdev->dev, "No clock specified\n");
> + rc = PTR_ERR(mtkd->clk);
> + return rc;
> + }
> +
> + if (of_property_read_bool(np, "dma-33bits"))
> + mtkd->support_33bits = true;
dma-33bits not defined in the binding description.
> +
> + if (mtkd->support_33bits)
> + bit_mask = 33;
> +
> + rc = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(bit_mask));
> + if (rc)
> + return rc;
> +
> + dma_cap_set(DMA_SLAVE, mtkd->ddev.cap_mask);
> + mtkd->ddev.device_alloc_chan_resources =
> + mtk_uart_apdma_alloc_chan_resources;
> + mtkd->ddev.device_free_chan_resources =
> + mtk_uart_apdma_free_chan_resources;
> + mtkd->ddev.device_tx_status = mtk_uart_apdma_tx_status;
> + mtkd->ddev.device_issue_pending = mtk_uart_apdma_issue_pending;
> + mtkd->ddev.device_prep_slave_sg = mtk_uart_apdma_prep_slave_sg;
> + mtkd->ddev.device_config = mtk_uart_apdma_slave_config;
> + mtkd->ddev.device_pause = mtk_uart_apdma_device_pause;
> + mtkd->ddev.device_terminate_all = mtk_uart_apdma_terminate_all;
> + mtkd->ddev.src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE);
> + mtkd->ddev.dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE);
> + mtkd->ddev.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
> + mtkd->ddev.residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT;
> + mtkd->ddev.dev = &pdev->dev;
> + INIT_LIST_HEAD(&mtkd->ddev.channels);
> +
> + mtkd->dma_requests = MTK_UART_APDMA_NR_VCHANS;
Do this if dma-requests property is not present.
> + if (of_property_read_u32(np, "dma-requests", &mtkd->dma_requests)) {
It's quite obvious what this does, but IMHO it should be reflected in the binding.
Regards,
Matthias
> + dev_info(&pdev->dev,
> + "Using %u as missing dma-requests property\n",
> + MTK_UART_APDMA_NR_VCHANS);
> + }
> +
> + mtkd->dma_irq = devm_kcalloc(&pdev->dev, mtkd->dma_requests,
> + sizeof(*mtkd->dma_irq), GFP_KERNEL);
> + if (!mtkd->dma_irq)
> + return -ENOMEM;
> +
> + for (i = 0; i < mtkd->dma_requests; i++) {
> + c = devm_kzalloc(mtkd->ddev.dev, sizeof(*c), GFP_KERNEL);
> + if (!c) {
> + rc = -ENODEV;
> + goto err_no_dma;
> + }
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, i);
> + if (!res) {
> + rc = -ENODEV;
> + goto err_no_dma;
> + }
> +
> + c->base = devm_ioremap_resource(&pdev->dev, res);
> + if (IS_ERR(c->base)) {
> + rc = PTR_ERR(c->base);
> + goto err_no_dma;
> + }
> + c->requested = false;
> + c->vc.desc_free = mtk_uart_apdma_desc_free;
> + vchan_init(&c->vc, &mtkd->ddev);
> +
> + mtkd->dma_irq[i] = platform_get_irq(pdev, i);
> + if ((int)mtkd->dma_irq[i] < 0) {
> + dev_err(&pdev->dev, "failed to get IRQ[%d]\n", i);
> + rc = -EINVAL;
> + goto err_no_dma;
> + }
> + }
> +
> + pm_runtime_enable(&pdev->dev);
> + pm_runtime_set_active(&pdev->dev);
> +
> + rc = dma_async_device_register(&mtkd->ddev);
> + if (rc)
> + goto rpm_disable;
> +
> + platform_set_drvdata(pdev, mtkd);
> +
> + /* Device-tree DMA controller registration */
> + rc = of_dma_controller_register(np, of_dma_xlate_by_chan_id, mtkd);
> + if (rc)
> + goto dma_remove;
> +
> + return rc;
> +
> +dma_remove:
> + dma_async_device_unregister(&mtkd->ddev);
> +rpm_disable:
> + pm_runtime_disable(&pdev->dev);
> +err_no_dma:
> + mtk_uart_apdma_free(mtkd);
> + return rc;
> +}
> +
> +static int mtk_uart_apdma_remove(struct platform_device *pdev)
> +{
> + struct mtk_uart_apdmadev *mtkd = platform_get_drvdata(pdev);
> +
> + if (pdev->dev.of_node)
> + of_dma_controller_free(pdev->dev.of_node);
> +
> + pm_runtime_disable(&pdev->dev);
> + pm_runtime_put_noidle(&pdev->dev);
> +
> + dma_async_device_unregister(&mtkd->ddev);
> + mtk_uart_apdma_free(mtkd);
> +
> + return 0;
> +}
> +
> +#ifdef CONFIG_PM_SLEEP
> +static int mtk_uart_apdma_suspend(struct device *dev)
> +{
> + struct mtk_uart_apdmadev *mtkd = dev_get_drvdata(dev);
> +
> + if (!pm_runtime_suspended(dev))
> + clk_disable_unprepare(mtkd->clk);
> +
> + return 0;
> +}
> +
> +static int mtk_uart_apdma_resume(struct device *dev)
> +{
> + int ret;
> + struct mtk_uart_apdmadev *mtkd = dev_get_drvdata(dev);
> +
> + if (!pm_runtime_suspended(dev)) {
> + ret = clk_prepare_enable(mtkd->clk);
> + if (ret)
> + return ret;
> + }
> +
> + return 0;
> +}
> +#endif /* CONFIG_PM_SLEEP */
> +
> +#ifdef CONFIG_PM
> +static int mtk_uart_apdma_runtime_suspend(struct device *dev)
> +{
> + struct mtk_uart_apdmadev *mtkd = dev_get_drvdata(dev);
> +
> + clk_disable_unprepare(mtkd->clk);
> +
> + return 0;
> +}
> +
> +static int mtk_uart_apdma_runtime_resume(struct device *dev)
> +{
> + int ret;
> + struct mtk_uart_apdmadev *mtkd = dev_get_drvdata(dev);
> +
> + ret = clk_prepare_enable(mtkd->clk);
> + if (ret)
> + return ret;
> +
> + return 0;
> +}
> +#endif /* CONFIG_PM */
> +
> +static const struct dev_pm_ops mtk_uart_apdma_pm_ops = {
> + SET_SYSTEM_SLEEP_PM_OPS(mtk_uart_apdma_suspend, mtk_uart_apdma_resume)
> + SET_RUNTIME_PM_OPS(mtk_uart_apdma_runtime_suspend,
> + mtk_uart_apdma_runtime_resume, NULL)
> +};
> +
> +static struct platform_driver mtk_uart_apdma_driver = {
> + .probe = mtk_uart_apdma_probe,
> + .remove = mtk_uart_apdma_remove,
> + .driver = {
> + .name = KBUILD_MODNAME,
> + .pm = &mtk_uart_apdma_pm_ops,
> + .of_match_table = of_match_ptr(mtk_uart_apdma_match),
> + },
> +};
> +
> +module_platform_driver(mtk_uart_apdma_driver);
> +
> +MODULE_DESCRIPTION("MediaTek UART APDMA Controller Driver");
> +MODULE_AUTHOR("Long Cheng <[email protected]>");
> +MODULE_LICENSE("GPL v2");
> +
>
On 18/01/2019 04:10, Long Cheng wrote:
> The filename matches mtk-uart-apdma.c.
> So using "mtk-uart-apdma.txt" should be better.
>
> Signed-off-by: Long Cheng <[email protected]>
> ---
> .../devicetree/bindings/dma/8250_mtk_dma.txt | 33 --------------------
> .../devicetree/bindings/dma/mtk-uart-apdma.txt | 33 ++++++++++++++++++++
> 2 files changed, 33 insertions(+), 33 deletions(-)
> delete mode 100644 Documentation/devicetree/bindings/dma/8250_mtk_dma.txt
> create mode 100644 Documentation/devicetree/bindings/dma/mtk-uart-apdma.txt
>
> diff --git a/Documentation/devicetree/bindings/dma/8250_mtk_dma.txt b/Documentation/devicetree/bindings/dma/8250_mtk_dma.txt
> deleted file mode 100644
> index 3fe0961..0000000
> --- a/Documentation/devicetree/bindings/dma/8250_mtk_dma.txt
> +++ /dev/null
> @@ -1,33 +0,0 @@
> -* Mediatek UART APDMA Controller
> -
> -Required properties:
> -- compatible should contain:
> - * "mediatek,mt2712-uart-dma" for MT2712 compatible APDMA
> - * "mediatek,mt6577-uart-dma" for MT6577 and all of the above
> -
> -- reg: The base address of the APDMA register bank.> -
> -- interrupts: A single interrupt specifier.
One interrupt per dma-request, or 8 if no dma-requests property is present.
> -
> -- clocks : Must contain an entry for each entry in clock-names.
> - See ../clocks/clock-bindings.txt for details.
> -- clock-names: The APDMA clock for register accesses> -
> -Examples:
> -
> - apdma: dma-controller@11000380 {
> - compatible = "mediatek,mt2712-uart-dma";
> - reg = <0 0x11000380 0 0x400>;
> - interrupts = <GIC_SPI 63 IRQ_TYPE_LEVEL_LOW>,
> - <GIC_SPI 64 IRQ_TYPE_LEVEL_LOW>,
> - <GIC_SPI 65 IRQ_TYPE_LEVEL_LOW>,
> - <GIC_SPI 66 IRQ_TYPE_LEVEL_LOW>,
> - <GIC_SPI 67 IRQ_TYPE_LEVEL_LOW>,
> - <GIC_SPI 68 IRQ_TYPE_LEVEL_LOW>,
> - <GIC_SPI 69 IRQ_TYPE_LEVEL_LOW>,
> - <GIC_SPI 70 IRQ_TYPE_LEVEL_LOW>;
> - clocks = <&pericfg CLK_PERI_AP_DMA>;
> - clock-names = "apdma";
> - #dma-cells = <1>;
> - };
> -
> diff --git a/Documentation/devicetree/bindings/dma/mtk-uart-apdma.txt b/Documentation/devicetree/bindings/dma/mtk-uart-apdma.txt
> new file mode 100644
> index 0000000..3fe0961
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/dma/mtk-uart-apdma.txt
> @@ -0,0 +1,33 @@
> +* Mediatek UART APDMA Controller
> +
> +Required properties:
> +- compatible should contain:
> + * "mediatek,mt2712-uart-dma" for MT2712 compatible APDMA
> + * "mediatek,mt6577-uart-dma" for MT6577 and all of the above
> +
> +- reg: The base address of the APDMA register bank.
> +
There is one address needed for every dma-request or 8 if dma-requests property
is not present. As already mentioned in the driver review dma-requests property
is missing.
> +- interrupts: A single interrupt specifier.
> +
> +- clocks : Must contain an entry for each entry in clock-names.
> + See ../clocks/clock-bindings.txt for details.
> +- clock-names: The APDMA clock for register accesses
> +
Missing option property dma-33bits (should be mtk,dma-33bits?).
> +Examples:
> +
> + apdma: dma-controller@11000380 {
> + compatible = "mediatek,mt2712-uart-dma";
> + reg = <0 0x11000380 0 0x400>;
We are missing the io mem areas here, right?
Regards,
Matthias
> + interrupts = <GIC_SPI 63 IRQ_TYPE_LEVEL_LOW>,
> + <GIC_SPI 64 IRQ_TYPE_LEVEL_LOW>,
> + <GIC_SPI 65 IRQ_TYPE_LEVEL_LOW>,
> + <GIC_SPI 66 IRQ_TYPE_LEVEL_LOW>,
> + <GIC_SPI 67 IRQ_TYPE_LEVEL_LOW>,
> + <GIC_SPI 68 IRQ_TYPE_LEVEL_LOW>,
> + <GIC_SPI 69 IRQ_TYPE_LEVEL_LOW>,
> + <GIC_SPI 70 IRQ_TYPE_LEVEL_LOW>;
> + clocks = <&pericfg CLK_PERI_AP_DMA>;
> + clock-names = "apdma";
> + #dma-cells = <1>;
> + };
> +
>
On 14-02-19, 10:44, Long Cheng wrote:
> On Mon, 2019-02-04 at 12:51 +0530, Vinod Koul wrote:
> > > +static int mtk_uart_apdma_device_pause(struct dma_chan *chan)
> > > +{
> > > + /* just for check caps pass */
> > > + return 0;
> > > +}
> >
> > please remove, this is not a mandatory fn
>
> Can't remove it. Before the mail, i had explained it. in 8250 uart
> framework, will check the function..
I think you should fix the 8250 uart to handle driver not having a
pause. Keeping a dummy pause is just wrong and sets wrong expectations
for uart..
--
~Vinod