Add driver for arm pl353 static memory controller. This controller is
used in xilinx zynq soc for interfacing the nand and nor/sram memory
devices.
Signed-off-by: Punnaiah Choudary Kalluri <[email protected]>
---
Changes in v6:
- Fixed checkpatch.pl reported warnings
- fixed missing space and dont enable this driver default
Changes in v5:
- Added pl353_smc_get_clkrate function, made pl353_smc_set_cycles as public
API
- Removed nand timing parameter initialization and moved it to nand driver
Changes in v4:
- Modified driver to support multiple instances
- Used sleep instaed of busywait for delay
Changes in v3:
- None
Changes in v2:
- Since now the timing parameters are in nano seconds, added logic to convert
them to the cycles
---
drivers/memory/Kconfig | 7 +
drivers/memory/Makefile | 2 +-
drivers/memory/pl353-smc.c | 526 ++++++++++++++++++++++++++++++++++++++
include/linux/memory/pl353-smc.h | 37 +++
4 files changed, 571 insertions(+), 1 deletions(-)
create mode 100644 drivers/memory/pl353-smc.c
create mode 100644 include/linux/memory/pl353-smc.h
diff --git a/drivers/memory/Kconfig b/drivers/memory/Kconfig
index 191383d8..7db4f74 100644
--- a/drivers/memory/Kconfig
+++ b/drivers/memory/Kconfig
@@ -83,6 +83,13 @@ config FSL_IFC
bool
depends on FSL_SOC
+config PL353_SMC
+ bool "ARM PL353 Static Memory Controller (SMC) driver"
+ depends on ARM
+ help
+ This driver is for the ARM PL353 Static Memory Controller (SMC)
+ module.
+
source "drivers/memory/tegra/Kconfig"
endif
diff --git a/drivers/memory/Makefile b/drivers/memory/Makefile
index 6b65481..8a112ac 100644
--- a/drivers/memory/Makefile
+++ b/drivers/memory/Makefile
@@ -13,5 +13,5 @@ obj-$(CONFIG_FSL_CORENET_CF) += fsl-corenet-cf.o
obj-$(CONFIG_FSL_IFC) += fsl_ifc.o
obj-$(CONFIG_MVEBU_DEVBUS) += mvebu-devbus.o
obj-$(CONFIG_TEGRA20_MC) += tegra20-mc.o
-
+obj-$(CONFIG_PL353_SMC) += pl353-smc.o
obj-$(CONFIG_TEGRA_MC) += tegra/
diff --git a/drivers/memory/pl353-smc.c b/drivers/memory/pl353-smc.c
new file mode 100644
index 0000000..b407b47
--- /dev/null
+++ b/drivers/memory/pl353-smc.c
@@ -0,0 +1,526 @@
+/*
+ * ARM PL353 SMC Driver
+ *
+ * Copyright (C) 2012 - 2014 Xilinx, Inc.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * Currently only a single SMC instance is supported.
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/memory/pl353-smc.h>
+#include <linux/module.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+/* Register definitions */
+#define PL353_SMC_MEMC_STATUS_OFFS 0 /* Controller status reg, RO */
+#define PL353_SMC_CFG_CLR_OFFS 0xC /* Clear config reg, WO */
+#define PL353_SMC_DIRECT_CMD_OFFS 0x10 /* Direct command reg, WO */
+#define PL353_SMC_SET_CYCLES_OFFS 0x14 /* Set cycles register, WO */
+#define PL353_SMC_SET_OPMODE_OFFS 0x18 /* Set opmode register, WO */
+#define PL353_SMC_ECC_STATUS_OFFS 0x400 /* ECC status register */
+#define PL353_SMC_ECC_MEMCFG_OFFS 0x404 /* ECC mem config reg */
+#define PL353_SMC_ECC_MEMCMD1_OFFS 0x408 /* ECC mem cmd1 reg */
+#define PL353_SMC_ECC_MEMCMD2_OFFS 0x40C /* ECC mem cmd2 reg */
+#define PL353_SMC_ECC_VALUE0_OFFS 0x418 /* ECC value 0 reg */
+
+/* Controller status register specific constants */
+#define PL353_SMC_MEMC_STATUS_RAW_INT_1_SHIFT 6
+
+/* Clear configuration register specific constants */
+#define PL353_SMC_CFG_CLR_INT_CLR_1 0x10
+#define PL353_SMC_CFG_CLR_ECC_INT_DIS_1 0x40
+#define PL353_SMC_CFG_CLR_INT_DIS_1 0x2
+#define PL353_SMC_CFG_CLR_DEFAULT_MASK (PL353_SMC_CFG_CLR_INT_CLR_1 | \
+ PL353_SMC_CFG_CLR_ECC_INT_DIS_1 | \
+ PL353_SMC_CFG_CLR_INT_DIS_1)
+
+/* Set cycles register specific constants */
+#define PL353_SMC_SET_CYCLES_T0_MASK 0xF
+#define PL353_SMC_SET_CYCLES_T0_SHIFT 0
+#define PL353_SMC_SET_CYCLES_T1_MASK 0xF
+#define PL353_SMC_SET_CYCLES_T1_SHIFT 4
+#define PL353_SMC_SET_CYCLES_T2_MASK 0x7
+#define PL353_SMC_SET_CYCLES_T2_SHIFT 8
+#define PL353_SMC_SET_CYCLES_T3_MASK 0x7
+#define PL353_SMC_SET_CYCLES_T3_SHIFT 11
+#define PL353_SMC_SET_CYCLES_T4_MASK 0x7
+#define PL353_SMC_SET_CYCLES_T4_SHIFT 14
+#define PL353_SMC_SET_CYCLES_T5_MASK 0x7
+#define PL353_SMC_SET_CYCLES_T5_SHIFT 17
+#define PL353_SMC_SET_CYCLES_T6_MASK 0xF
+#define PL353_SMC_SET_CYCLES_T6_SHIFT 20
+
+/* ECC status register specific constants */
+#define PL353_SMC_ECC_STATUS_BUSY (1 << 6)
+
+/* ECC memory config register specific constants */
+#define PL353_SMC_ECC_MEMCFG_MODE_MASK 0xC
+#define PL353_SMC_ECC_MEMCFG_MODE_SHIFT 2
+#define PL353_SMC_ECC_MEMCFG_PGSIZE_MASK 0xC
+
+#define PL353_SMC_DC_UPT_NAND_REGS ((4 << 23) | /* CS: NAND chip */ \
+ (2 << 21)) /* UpdateRegs operation */
+
+#define PL353_NAND_ECC_CMD1 ((0x80) | /* Write command */ \
+ (0 << 8) | /* Read command */ \
+ (0x30 << 16) | /* Read End command */ \
+ (1 << 24)) /* Read End command calid */
+
+#define PL353_NAND_ECC_CMD2 ((0x85) | /* Write col change cmd */ \
+ (5 << 8) | /* Read col change cmd */ \
+ (0xE0 << 16) | /* Read col change end cmd */ \
+ (1 << 24)) /* Read col change end cmd valid */
+#define PL353_NAND_ECC_BUSY_TIMEOUT (1 * HZ)
+
+/**
+ * struct pl353_smc_data - Private smc driver structure
+ * @base: SMC virtual register space
+ * @devclk: Pointer to the peripheral clock
+ * @aperclk: Pointer to the APER clock
+ */
+struct pl353_smc_data {
+ void __iomem *base;
+ struct clk *memclk;
+ struct clk *aclk;
+};
+
+/**
+ * pl353_smc_set_buswidth - Set memory buswidth
+ * @dev: Pointer to the device struct
+ * @bw: Memory buswidth (8 | 16)
+ * Return: 0 on success or negative errno.
+ */
+int pl353_smc_set_buswidth(struct device *dev, unsigned int bw)
+{
+ struct pl353_smc_data *pl353_smc = dev_get_drvdata(dev);
+
+ if (bw != PL353_SMC_MEM_WIDTH_8 && bw != PL353_SMC_MEM_WIDTH_16)
+ return -EINVAL;
+
+ writel(bw, pl353_smc->base + PL353_SMC_SET_OPMODE_OFFS);
+ writel(PL353_SMC_DC_UPT_NAND_REGS, pl353_smc->base +
+ PL353_SMC_DIRECT_CMD_OFFS);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(pl353_smc_set_buswidth);
+
+/**
+ * pl353_smc_set_cycles - Set memory timing parameters
+ * @dev: Pointer to the device struct
+ * @t0: t_rc read cycle time
+ * @t1: t_wc write cycle time
+ * @t2: t_rea/t_ceoe output enable assertion delay
+ * @t3: t_wp write enable deassertion delay
+ * @t4: t_clr/t_pc page cycle time
+ * @t5: t_ar/t_ta ID read time/turnaround time
+ * @t6: t_rr busy to RE timing
+ *
+ * Sets NAND chip specific timing parameters.
+ */
+void pl353_smc_set_cycles(struct device *dev, u32 t0, u32 t1, u32 t2, u32 t3,
+ u32 t4, u32 t5, u32 t6)
+{
+ struct pl353_smc_data *pl353_smc = dev_get_drvdata(dev);
+
+ t0 &= PL353_SMC_SET_CYCLES_T0_MASK;
+ t1 = (t1 & PL353_SMC_SET_CYCLES_T1_MASK) <<
+ PL353_SMC_SET_CYCLES_T1_SHIFT;
+ t2 = (t2 & PL353_SMC_SET_CYCLES_T2_MASK) <<
+ PL353_SMC_SET_CYCLES_T2_SHIFT;
+ t3 = (t3 & PL353_SMC_SET_CYCLES_T3_MASK) <<
+ PL353_SMC_SET_CYCLES_T3_SHIFT;
+ t4 = (t4 & PL353_SMC_SET_CYCLES_T4_MASK) <<
+ PL353_SMC_SET_CYCLES_T4_SHIFT;
+ t5 = (t5 & PL353_SMC_SET_CYCLES_T5_MASK) <<
+ PL353_SMC_SET_CYCLES_T5_SHIFT;
+ t6 = (t6 & PL353_SMC_SET_CYCLES_T6_MASK) <<
+ PL353_SMC_SET_CYCLES_T6_SHIFT;
+
+ t0 |= t1 | t2 | t3 | t4 | t5 | t6;
+
+ writel(t0, pl353_smc->base + PL353_SMC_SET_CYCLES_OFFS);
+ writel(PL353_SMC_DC_UPT_NAND_REGS, pl353_smc->base +
+ PL353_SMC_DIRECT_CMD_OFFS);
+}
+EXPORT_SYMBOL_GPL(pl353_smc_set_cycles);
+
+/**
+ * pl353_smc_ecc_is_busy_noirq - Read ecc busy flag
+ * @dev: Pointer to the device struct
+ * Return: the ecc_status bit from the ecc_status register. 1 = busy, 0 = idle
+ */
+static int pl353_smc_ecc_is_busy_noirq(struct device *dev)
+{
+ struct pl353_smc_data *pl353_smc = dev_get_drvdata(dev);
+
+ return !!(readl(pl353_smc->base + PL353_SMC_ECC_STATUS_OFFS) &
+ PL353_SMC_ECC_STATUS_BUSY);
+}
+
+/**
+ * pl353_smc_ecc_is_busy - Read ecc busy flag
+ * @dev: Pointer to the device struct
+ * Return: the ecc_status bit from the ecc_status register. 1 = busy, 0 = idle
+ */
+int pl353_smc_ecc_is_busy(struct device *dev)
+{
+ int ret;
+
+ ret = pl353_smc_ecc_is_busy_noirq(dev);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(pl353_smc_ecc_is_busy);
+
+/**
+ * pl353_smc_get_ecc_val - Read ecc_valueN registers
+ * @dev: Pointer to the device struct
+ * @ecc_reg: Index of the ecc_value reg (0..3)
+ * Return: the content of the requested ecc_value register.
+ *
+ * There are four valid ecc_value registers. The argument is truncated to stay
+ * within this valid boundary.
+ */
+u32 pl353_smc_get_ecc_val(struct device *dev, int ecc_reg)
+{
+ struct pl353_smc_data *pl353_smc = dev_get_drvdata(dev);
+ u32 addr, reg;
+
+ ecc_reg &= 3;
+ addr = PL353_SMC_ECC_VALUE0_OFFS + (ecc_reg << 2);
+ reg = readl(pl353_smc->base + addr);
+
+ return reg;
+}
+EXPORT_SYMBOL_GPL(pl353_smc_get_ecc_val);
+
+/**
+ * pl353_smc_get_nand_int_status_raw - Get NAND interrupt status bit
+ * @dev: Pointer to the device struct
+ * Return: the raw_int_status1 bit from the memc_status register
+ */
+int pl353_smc_get_nand_int_status_raw(struct device *dev)
+{
+ struct pl353_smc_data *pl353_smc = dev_get_drvdata(dev);
+ u32 reg;
+
+ reg = readl(pl353_smc->base + PL353_SMC_MEMC_STATUS_OFFS);
+ reg >>= PL353_SMC_MEMC_STATUS_RAW_INT_1_SHIFT;
+ reg &= 1;
+
+ return reg;
+}
+EXPORT_SYMBOL_GPL(pl353_smc_get_nand_int_status_raw);
+
+/**
+ * pl353_smc_clr_nand_int - Clear NAND interrupt
+ * @dev: Pointer to the device struct
+ */
+void pl353_smc_clr_nand_int(struct device *dev)
+{
+ struct pl353_smc_data *pl353_smc = dev_get_drvdata(dev);
+
+ writel(PL353_SMC_CFG_CLR_INT_CLR_1,
+ pl353_smc->base + PL353_SMC_CFG_CLR_OFFS);
+}
+EXPORT_SYMBOL_GPL(pl353_smc_clr_nand_int);
+
+/**
+ * pl353_smc_set_ecc_mode - Set SMC ECC mode
+ * @dev: Pointer to the device struct
+ * @mode: ECC mode (BYPASS, APB, MEM)
+ * Return: 0 on success or negative errno.
+ */
+int pl353_smc_set_ecc_mode(struct device *dev, enum pl353_smc_ecc_mode mode)
+{
+ struct pl353_smc_data *pl353_smc = dev_get_drvdata(dev);
+ u32 reg;
+ int ret = 0;
+
+ switch (mode) {
+ case PL353_SMC_ECCMODE_BYPASS:
+ case PL353_SMC_ECCMODE_APB:
+ case PL353_SMC_ECCMODE_MEM:
+
+ reg = readl(pl353_smc->base + PL353_SMC_ECC_MEMCFG_OFFS);
+ reg &= ~PL353_SMC_ECC_MEMCFG_MODE_MASK;
+ reg |= mode << PL353_SMC_ECC_MEMCFG_MODE_SHIFT;
+ writel(reg, pl353_smc->base + PL353_SMC_ECC_MEMCFG_OFFS);
+
+ break;
+ default:
+ ret = -EINVAL;
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(pl353_smc_set_ecc_mode);
+
+/**
+ * pl353_smc_set_ecc_pg_size - Set SMC ECC page size
+ * @dev: Pointer to the device struct
+ * @pg_sz: ECC page size
+ * Return: 0 on success or negative errno.
+ */
+int pl353_smc_set_ecc_pg_size(struct device *dev, unsigned int pg_sz)
+{
+ struct pl353_smc_data *pl353_smc = dev_get_drvdata(dev);
+ u32 reg, sz;
+
+ switch (pg_sz) {
+ case 0:
+ sz = 0;
+ break;
+ case 512:
+ sz = 1;
+ break;
+ case 1024:
+ sz = 2;
+ break;
+ case 2048:
+ sz = 3;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ reg = readl(pl353_smc->base + PL353_SMC_ECC_MEMCFG_OFFS);
+ reg &= ~PL353_SMC_ECC_MEMCFG_PGSIZE_MASK;
+ reg |= sz;
+ writel(reg, pl353_smc->base + PL353_SMC_ECC_MEMCFG_OFFS);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(pl353_smc_set_ecc_pg_size);
+
+
+/**
+ * pl353_smc_get_clkrate - Obtain the current clock rate
+ * @dev: Pointer to the device struct
+ * Return: the current clock rate.
+ */
+ulong pl353_smc_get_clkrate(struct device *dev)
+{
+ struct pl353_smc_data *pl353_smc = dev_get_drvdata(dev);
+
+ return clk_get_rate(pl353_smc->memclk);
+}
+EXPORT_SYMBOL_GPL(pl353_smc_get_clkrate);
+
+static int __maybe_unused pl353_smc_suspend(struct device *dev)
+{
+ struct pl353_smc_data *pl353_smc = dev_get_drvdata(dev);
+
+ clk_disable(pl353_smc->memclk);
+ clk_disable(pl353_smc->aclk);
+
+ return 0;
+}
+
+static int __maybe_unused pl353_smc_resume(struct device *dev)
+{
+ int ret;
+ struct pl353_smc_data *pl353_smc = dev_get_drvdata(dev);
+
+ ret = clk_enable(pl353_smc->aclk);
+ if (ret) {
+ dev_err(dev, "Cannot enable axi domain clock.\n");
+ return ret;
+ }
+
+ ret = clk_enable(pl353_smc->memclk);
+ if (ret) {
+ dev_err(dev, "Cannot enable memory clock.\n");
+ clk_disable(pl353_smc->aclk);
+ return ret;
+ }
+ return ret;
+}
+
+static SIMPLE_DEV_PM_OPS(pl353_smc_dev_pm_ops, pl353_smc_suspend,
+ pl353_smc_resume);
+
+/**
+ * pl353_smc_init_nand_interface - Initialize the NAND interface
+ * @pdev: Pointer to the platform_device struct
+ * @nand_node: Pointer to the pl353_nand device_node struct
+ */
+static void pl353_smc_init_nand_interface(struct platform_device *pdev,
+ struct device_node *nand_node)
+{
+ unsigned long timeout = jiffies + PL353_NAND_ECC_BUSY_TIMEOUT;
+ struct pl353_smc_data *pl353_smc = platform_get_drvdata(pdev);
+
+ pl353_smc_set_buswidth(&pdev->dev, PL353_SMC_MEM_WIDTH_8);
+
+ writel(PL353_SMC_CFG_CLR_INT_CLR_1,
+ pl353_smc->base + PL353_SMC_CFG_CLR_OFFS);
+ writel(PL353_SMC_DC_UPT_NAND_REGS, pl353_smc->base +
+ PL353_SMC_DIRECT_CMD_OFFS);
+ /* Wait till the ECC operation is complete */
+ do {
+ if (pl353_smc_ecc_is_busy_noirq(&pdev->dev))
+ msleep(1);
+ else
+ break;
+ } while (!time_after_eq(jiffies, timeout));
+
+ if (time_after_eq(jiffies, timeout))
+ dev_err(&pdev->dev, "nand ecc busy status timed out");
+ /* Set the command1 and command2 register */
+ writel(PL353_NAND_ECC_CMD1,
+ pl353_smc->base + PL353_SMC_ECC_MEMCMD1_OFFS);
+ writel(PL353_NAND_ECC_CMD2,
+ pl353_smc->base + PL353_SMC_ECC_MEMCMD2_OFFS);
+}
+
+static const struct of_device_id matches_nor[] = {
+ { .compatible = "cfi-flash" },
+ {}
+};
+
+static const struct of_device_id matches_nand[] = {
+ { .compatible = "arm,pl353-nand-r2p1" },
+ {}
+};
+
+static int pl353_smc_probe(struct platform_device *pdev)
+{
+ struct pl353_smc_data *pl353_smc;
+ struct device_node *child;
+ struct resource *res;
+ int err;
+ struct device_node *of_node = pdev->dev.of_node;
+ const struct of_device_id *matches = NULL;
+
+ pl353_smc = devm_kzalloc(&pdev->dev, sizeof(*pl353_smc), GFP_KERNEL);
+ if (!pl353_smc)
+ return -ENOMEM;
+
+ /* Get the NAND controller virtual address */
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ pl353_smc->base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(pl353_smc->base))
+ return PTR_ERR(pl353_smc->base);
+
+ pl353_smc->aclk = devm_clk_get(&pdev->dev, "aclk");
+ if (IS_ERR(pl353_smc->aclk)) {
+ dev_err(&pdev->dev, "aclk clock not found.\n");
+ return PTR_ERR(pl353_smc->aclk);
+ }
+
+ pl353_smc->memclk = devm_clk_get(&pdev->dev, "memclk");
+ if (IS_ERR(pl353_smc->memclk)) {
+ dev_err(&pdev->dev, "memclk clock not found.\n");
+ return PTR_ERR(pl353_smc->memclk);
+ }
+
+ err = clk_prepare_enable(pl353_smc->aclk);
+ if (err) {
+ dev_err(&pdev->dev, "Unable to enable AXI clock.\n");
+ return err;
+ }
+
+ err = clk_prepare_enable(pl353_smc->memclk);
+ if (err) {
+ dev_err(&pdev->dev, "Unable to enable memory clock.\n");
+ goto out_clk_dis_aper;
+ }
+
+ platform_set_drvdata(pdev, pl353_smc);
+
+ /* clear interrupts */
+ writel(PL353_SMC_CFG_CLR_DEFAULT_MASK,
+ pl353_smc->base + PL353_SMC_CFG_CLR_OFFS);
+
+ /* Find compatible children. Only a single child is supported */
+ for_each_available_child_of_node(of_node, child) {
+ if (of_match_node(matches_nand, child)) {
+ pl353_smc_init_nand_interface(pdev, child);
+ if (!matches) {
+ matches = matches_nand;
+ } else {
+ dev_err(&pdev->dev,
+ "incompatible configuration\n");
+ goto out_clk_disable;
+ }
+ }
+
+ if (of_match_node(matches_nor, child)) {
+ static int counts;
+
+ if (!matches) {
+ matches = matches_nor;
+ } else {
+ if (matches != matches_nor || counts > 1) {
+ dev_err(&pdev->dev,
+ "incompatible configuration\n");
+ goto out_clk_disable;
+ }
+ }
+ counts++;
+ }
+ }
+
+ if (matches)
+ of_platform_populate(of_node, matches, NULL, &pdev->dev);
+
+ return 0;
+
+out_clk_disable:
+ clk_disable_unprepare(pl353_smc->memclk);
+out_clk_dis_aper:
+ clk_disable_unprepare(pl353_smc->aclk);
+
+ return err;
+}
+
+static int pl353_smc_remove(struct platform_device *pdev)
+{
+ struct pl353_smc_data *pl353_smc = platform_get_drvdata(pdev);
+
+ clk_disable_unprepare(pl353_smc->memclk);
+ clk_disable_unprepare(pl353_smc->aclk);
+
+ return 0;
+}
+
+/* Match table for device tree binding */
+static const struct of_device_id pl353_smc_of_match[] = {
+ { .compatible = "arm,pl353-smc-r2p1" },
+ { },
+};
+MODULE_DEVICE_TABLE(of, pl353_smc_of_match);
+
+static struct platform_driver pl353_smc_driver = {
+ .probe = pl353_smc_probe,
+ .remove = pl353_smc_remove,
+ .driver = {
+ .name = "pl353-smc",
+ .owner = THIS_MODULE,
+ .pm = &pl353_smc_dev_pm_ops,
+ .of_match_table = pl353_smc_of_match,
+ },
+};
+
+module_platform_driver(pl353_smc_driver);
+
+MODULE_AUTHOR("Xilinx, Inc.");
+MODULE_DESCRIPTION("ARM PL353 SMC Driver");
+MODULE_LICENSE("GPL v2");
diff --git a/include/linux/memory/pl353-smc.h b/include/linux/memory/pl353-smc.h
new file mode 100644
index 0000000..cdc31bf
--- /dev/null
+++ b/include/linux/memory/pl353-smc.h
@@ -0,0 +1,37 @@
+/*
+ * ARM PL353 SMC Driver Header
+ *
+ * Copyright (C) 2012 Xilinx, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License version 2 as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ */
+
+#ifndef __LINUX_MEMORY_PL353_SMC_H
+#define __LINUX_MEMORY_PL353_SMC_H
+
+enum pl353_smc_ecc_mode {
+ PL353_SMC_ECCMODE_BYPASS = 0,
+ PL353_SMC_ECCMODE_APB = 1,
+ PL353_SMC_ECCMODE_MEM = 2
+};
+
+enum pl353_smc_mem_width {
+ PL353_SMC_MEM_WIDTH_8 = 0,
+ PL353_SMC_MEM_WIDTH_16 = 1
+};
+
+u32 pl353_smc_get_ecc_val(struct device *dev, int ecc_reg);
+int pl353_smc_ecc_is_busy(struct device *dev);
+int pl353_smc_get_nand_int_status_raw(struct device *dev);
+void pl353_smc_clr_nand_int(struct device *dev);
+int pl353_smc_set_ecc_mode(struct device *dev, enum pl353_smc_ecc_mode mode);
+int pl353_smc_set_ecc_pg_size(struct device *dev, unsigned int pg_sz);
+int pl353_smc_set_buswidth(struct device *dev, unsigned int bw);
+void pl353_smc_set_cycles(struct device *dev, u32 t0, u32 t1, u32 t2, u32 t3,
+ u32 t4, u32 t5, u32 t6);
+ulong pl353_smc_get_clkrate(struct device *dev);
+
+#endif
--
1.7.4
On Mon, 2015-04-13 at 21:41 +0530, Punnaiah Choudary Kalluri wrote:
> --- a/drivers/memory/Kconfig
> +++ b/drivers/memory/Kconfig
> +config PL353_SMC
> + bool "ARM PL353 Static Memory Controller (SMC) driver"
> + depends on ARM
> + help
> + This driver is for the ARM PL353 Static Memory Controller (SMC)
> + module.
This adds a bool symbol.
> --- a/drivers/memory/Makefile
> +++ b/drivers/memory/Makefile
> +obj-$(CONFIG_PL353_SMC) += pl353-smc.o
Which means pl353-smc.o can never be part of a module, right?
(If that's not right you can stop reading here.)
> --- /dev/null
> +++ b/drivers/memory/pl353-smc.c
> + * This program is free software: you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation, either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
This states the license is GPL v2 or later.
> +#include <linux/module.h>
I wonder whether this include is needed, since this is built-in only
code.
> +MODULE_DEVICE_TABLE(of, pl353_smc_of_match);
According to include/linux/module.h this will be preprocessed away for
built-in code.
> +static struct platform_driver pl353_smc_driver = {
> + .probe = pl353_smc_probe,
> + .remove = pl353_smc_remove,
> + .driver = {
> + .name = "pl353-smc",
> + .owner = THIS_MODULE,
THIS_MODULE will be equivalent to NULL for built-in code, according to
include/linux/export.h.
> + .pm = &pl353_smc_dev_pm_ops,
> + .of_match_table = pl353_smc_of_match,
> + },
> +};
> +module_platform_driver(pl353_smc_driver);
Speaking from memory: for built-in only code this is equivalent to
having a wrapper that only does
register_platform_driver(&pl353_smc_driver);
and mark that wrapper with device_initcall().
> +MODULE_AUTHOR("Xilinx, Inc.");
> +MODULE_DESCRIPTION("ARM PL353 SMC Driver");
> +MODULE_LICENSE("GPL v2");
For built-in only code these macros will be effectively preprocessed
away.
(Would you make PL353_SMC a tristate symbol then you should note that
according to include/linux/module.h "GPL" is the license ident that
matches the license stated in the comment at the top of this file.)
Thanks,
Paul Bolle
Hi Paul Bolle
On Tue, Apr 14, 2015 at 12:19 AM, Paul Bolle <[email protected]> wrote:
> On Mon, 2015-04-13 at 21:41 +0530, Punnaiah Choudary Kalluri wrote:
>> --- a/drivers/memory/Kconfig
>> +++ b/drivers/memory/Kconfig
>
>> +config PL353_SMC
>> + bool "ARM PL353 Static Memory Controller (SMC) driver"
>> + depends on ARM
>> + help
>> + This driver is for the ARM PL353 Static Memory Controller (SMC)
>> + module.
>
> This adds a bool symbol.
>
>> --- a/drivers/memory/Makefile
>> +++ b/drivers/memory/Makefile
>
>> +obj-$(CONFIG_PL353_SMC) += pl353-smc.o
>
> Which means pl353-smc.o can never be part of a module, right?
>
> (If that's not right you can stop reading here.)
>
>> --- /dev/null
>> +++ b/drivers/memory/pl353-smc.c
>
>> + * This program is free software: you can redistribute it and/or modify
>> + * it under the terms of the GNU General Public License as published by
>> + * the Free Software Foundation, either version 2 of the License, or
>> + * (at your option) any later version.
>> + *
>> + * This program is distributed in the hope that it will be useful,
>> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
>> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
>> + * GNU General Public License for more details.
>
> This states the license is GPL v2 or later.
>
>> +#include <linux/module.h>
>
> I wonder whether this include is needed, since this is built-in only
> code.
>
>> +MODULE_DEVICE_TABLE(of, pl353_smc_of_match);
>
> According to include/linux/module.h this will be preprocessed away for
> built-in code.
>
>> +static struct platform_driver pl353_smc_driver = {
>> + .probe = pl353_smc_probe,
>> + .remove = pl353_smc_remove,
>> + .driver = {
>> + .name = "pl353-smc",
>> + .owner = THIS_MODULE,
>
> THIS_MODULE will be equivalent to NULL for built-in code, according to
> include/linux/export.h.
>
>> + .pm = &pl353_smc_dev_pm_ops,
>> + .of_match_table = pl353_smc_of_match,
>> + },
>> +};
>
>> +module_platform_driver(pl353_smc_driver);
>
> Speaking from memory: for built-in only code this is equivalent to
> having a wrapper that only does
> register_platform_driver(&pl353_smc_driver);
>
> and mark that wrapper with device_initcall().
>
>> +MODULE_AUTHOR("Xilinx, Inc.");
>> +MODULE_DESCRIPTION("ARM PL353 SMC Driver");
>> +MODULE_LICENSE("GPL v2");
>
> For built-in only code these macros will be effectively preprocessed
> away.
>
> (Would you make PL353_SMC a tristate symbol then you should note that
> according to include/linux/module.h "GPL" is the license ident that
> matches the license stated in the comment at the top of this file.)
Ok. I will make PL353_SMC as tristate symbol and also i will change the
licence ident to "GPL".
Thanks for the review.
I will wait some time for further functional comments on this driver before
sending the next version of patches
Thanks,
Punnaiah
>
> Thanks,
>
>
> Paul Bolle
>
Hi Punnaiah,
> +/**
> + * pl353_smc_set_cycles - Set memory timing parameters
> + * @dev: Pointer to the device struct
> + * @t0: t_rc read cycle time
> + * @t1: t_wc write cycle time
> + * @t2: t_rea/t_ceoe output enable assertion delay
> + * @t3: t_wp write enable deassertion delay
> + * @t4: t_clr/t_pc page cycle time
> + * @t5: t_ar/t_ta ID read time/turnaround time
> + * @t6: t_rr busy to RE timing
> + *
> + * Sets NAND chip specific timing parameters.
> + */
> +void pl353_smc_set_cycles(struct device *dev, u32 t0, u32 t1, u32 t2, u32 t3,
> + u32 t4, u32 t5, u32 t6)
> +{
> + struct pl353_smc_data *pl353_smc = dev_get_drvdata(dev);
> +
> + t0 &= PL353_SMC_SET_CYCLES_T0_MASK;
> + t1 = (t1 & PL353_SMC_SET_CYCLES_T1_MASK) <<
> + PL353_SMC_SET_CYCLES_T1_SHIFT;
> + t2 = (t2 & PL353_SMC_SET_CYCLES_T2_MASK) <<
> + PL353_SMC_SET_CYCLES_T2_SHIFT;
> + t3 = (t3 & PL353_SMC_SET_CYCLES_T3_MASK) <<
> + PL353_SMC_SET_CYCLES_T3_SHIFT;
> + t4 = (t4 & PL353_SMC_SET_CYCLES_T4_MASK) <<
> + PL353_SMC_SET_CYCLES_T4_SHIFT;
> + t5 = (t5 & PL353_SMC_SET_CYCLES_T5_MASK) <<
> + PL353_SMC_SET_CYCLES_T5_SHIFT;
> + t6 = (t6 & PL353_SMC_SET_CYCLES_T6_MASK) <<
> + PL353_SMC_SET_CYCLES_T6_SHIFT;
Right now, if the caller (i.e. the PL353 NAND driver) passes in a value for any
of the timing parameters that is too large, it will be truncated with the
corresponding mask and then saved, resulting in unexpected behavior. I saw
this when the PL353 NAND driver tried to set t_rc and t_wc to 17 cycles, which
does not fit in the 4-bit fields for those values -- it got clipped to 4 bits
and stored as 1 cycle, which made communication with the NAND chip fail and
time out.
It would be good to sanity-check each timing here, and rather than returning
void, return a return code indicating success or failure (e.g. -EINVAL for
invalid timings).
Note also that truncation isn't the only thing to check for here. The PL350
r2p1 datasheet lists a "Minimum permitted value" for each of these timing
values.
> +
> + t0 |= t1 | t2 | t3 | t4 | t5 | t6;
> +
> + writel(t0, pl353_smc->base + PL353_SMC_SET_CYCLES_OFFS);
> + writel(PL353_SMC_DC_UPT_NAND_REGS, pl353_smc->base +
> + PL353_SMC_DIRECT_CMD_OFFS);
> +}
> +EXPORT_SYMBOL_GPL(pl353_smc_set_cycles);
> +
Thanks,
Ben
Hi Ben,
I will take care of the boundary conditions for both lower and upper
limits and update the patches accordingly.
Thanks,
Punnaiah
On Tue, Apr 28, 2015 at 8:41 PM, Ben Shelton <[email protected]> wrote:
> Hi Punnaiah,
>
>> +/**
>> + * pl353_smc_set_cycles - Set memory timing parameters
>> + * @dev: Pointer to the device struct
>> + * @t0: t_rc read cycle time
>> + * @t1: t_wc write cycle time
>> + * @t2: t_rea/t_ceoe output enable assertion delay
>> + * @t3: t_wp write enable deassertion delay
>> + * @t4: t_clr/t_pc page cycle time
>> + * @t5: t_ar/t_ta ID read time/turnaround time
>> + * @t6: t_rr busy to RE timing
>> + *
>> + * Sets NAND chip specific timing parameters.
>> + */
>> +void pl353_smc_set_cycles(struct device *dev, u32 t0, u32 t1, u32 t2, u32 t3,
>> + u32 t4, u32 t5, u32 t6)
>> +{
>> + struct pl353_smc_data *pl353_smc = dev_get_drvdata(dev);
>> +
>> + t0 &= PL353_SMC_SET_CYCLES_T0_MASK;
>> + t1 = (t1 & PL353_SMC_SET_CYCLES_T1_MASK) <<
>> + PL353_SMC_SET_CYCLES_T1_SHIFT;
>> + t2 = (t2 & PL353_SMC_SET_CYCLES_T2_MASK) <<
>> + PL353_SMC_SET_CYCLES_T2_SHIFT;
>> + t3 = (t3 & PL353_SMC_SET_CYCLES_T3_MASK) <<
>> + PL353_SMC_SET_CYCLES_T3_SHIFT;
>> + t4 = (t4 & PL353_SMC_SET_CYCLES_T4_MASK) <<
>> + PL353_SMC_SET_CYCLES_T4_SHIFT;
>> + t5 = (t5 & PL353_SMC_SET_CYCLES_T5_MASK) <<
>> + PL353_SMC_SET_CYCLES_T5_SHIFT;
>> + t6 = (t6 & PL353_SMC_SET_CYCLES_T6_MASK) <<
>> + PL353_SMC_SET_CYCLES_T6_SHIFT;
>
> Right now, if the caller (i.e. the PL353 NAND driver) passes in a value for any
> of the timing parameters that is too large, it will be truncated with the
> corresponding mask and then saved, resulting in unexpected behavior. I saw
> this when the PL353 NAND driver tried to set t_rc and t_wc to 17 cycles, which
> does not fit in the 4-bit fields for those values -- it got clipped to 4 bits
> and stored as 1 cycle, which made communication with the NAND chip fail and
> time out.
>
> It would be good to sanity-check each timing here, and rather than returning
> void, return a return code indicating success or failure (e.g. -EINVAL for
> invalid timings).
>
> Note also that truncation isn't the only thing to check for here. The PL350
> r2p1 datasheet lists a "Minimum permitted value" for each of these timing
> values.
>
>> +
>> + t0 |= t1 | t2 | t3 | t4 | t5 | t6;
>> +
>> + writel(t0, pl353_smc->base + PL353_SMC_SET_CYCLES_OFFS);
>> + writel(PL353_SMC_DC_UPT_NAND_REGS, pl353_smc->base +
>> + PL353_SMC_DIRECT_CMD_OFFS);
>> +}
>> +EXPORT_SYMBOL_GPL(pl353_smc_set_cycles);
>> +
>
> Thanks,
> Ben