The platform data can now specify which external memory banks to probe
for NAND chips, and in which order. Banks that contain a NAND are used
and the other banks are freed.
Squashed version of development done in jz-2.6.38 branch.
Original patch by Lars-Peter Clausen with some bug fixes from me.
Thanks to Paul Cercueil for the initial autodetection patch.
Signed-off-by: Maarten ter Huurne <maarten@xxxxxxxxxxxxxx>
---
arch/mips/include/asm/mach-jz4740/jz4740_nand.h | 4 +
arch/mips/jz4740/platform.c | 20 ++-
drivers/mtd/nand/jz4740_nand.c | 226 +++++++++++++++++++----
3 files changed, 214 insertions(+), 36 deletions(-)
diff --git a/arch/mips/include/asm/mach-jz4740/jz4740_nand.h b/arch/mips/include/asm/mach-jz4740/jz4740_nand.h
index bb5b9a4..986982d 100644
--- a/arch/mips/include/asm/mach-jz4740/jz4740_nand.h
+++ b/arch/mips/include/asm/mach-jz4740/jz4740_nand.h
@@ -19,6 +19,8 @@
#include <linux/mtd/nand.h>
#include <linux/mtd/partitions.h>
+#define JZ_NAND_NUM_BANKS 4
+
struct jz_nand_platform_data {
int num_partitions;
struct mtd_partition *partitions;
@@ -27,6 +29,8 @@ struct jz_nand_platform_data {
unsigned int busy_gpio;
+ unsigned char banks[JZ_NAND_NUM_BANKS];
+
void (*ident_callback)(struct platform_device *, struct nand_chip *,
struct mtd_partition **, int *num_partitions);
};
diff --git a/arch/mips/jz4740/platform.c b/arch/mips/jz4740/platform.c
index 10929e2..e342ed4 100644
--- a/arch/mips/jz4740/platform.c
+++ b/arch/mips/jz4740/platform.c
@@ -157,11 +157,29 @@ static struct resource jz4740_nand_resources[] = {
.flags = IORESOURCE_MEM,
},
{
- .name = "bank",
+ .name = "bank1",
.start = 0x18000000,
.end = 0x180C0000 - 1,
.flags = IORESOURCE_MEM,
},
+ {
+ .name = "bank2",
+ .start = 0x14000000,
+ .end = 0x140C0000 - 1,
+ .flags = IORESOURCE_MEM,
+ },
+ {
+ .name = "bank3",
+ .start = 0x0C000000,
+ .end = 0x0C0C0000 - 1,
+ .flags = IORESOURCE_MEM,
+ },
+ {
+ .name = "bank4",
+ .start = 0x08000000,
+ .end = 0x080C0000 - 1,
+ .flags = IORESOURCE_MEM,
+ },
};
struct platform_device jz4740_nand_device = {
diff --git a/drivers/mtd/nand/jz4740_nand.c b/drivers/mtd/nand/jz4740_nand.c
index ac3b9f2..7084a2b 100644
--- a/drivers/mtd/nand/jz4740_nand.c
+++ b/drivers/mtd/nand/jz4740_nand.c
@@ -52,9 +52,10 @@
#define JZ_NAND_CTRL_ENABLE_CHIP(x) BIT((x) << 1)
#define JZ_NAND_CTRL_ASSERT_CHIP(x) BIT(((x) << 1) + 1)
+#define JZ_NAND_CTRL_ASSERT_CHIP_MASK 0xaa
-#define JZ_NAND_MEM_ADDR_OFFSET 0x10000
#define JZ_NAND_MEM_CMD_OFFSET 0x08000
+#define JZ_NAND_MEM_ADDR_OFFSET 0x10000
struct jz_nand {
struct mtd_info mtd;
@@ -62,8 +63,11 @@ struct jz_nand {
void __iomem *base;
struct resource *mem;
- void __iomem *bank_base;
- struct resource *bank_mem;
+ unsigned char banks[JZ_NAND_NUM_BANKS];
+ void __iomem *bank_base[JZ_NAND_NUM_BANKS];
+ struct resource *bank_mem[JZ_NAND_NUM_BANKS];
+
+ int selected_bank;
struct jz_nand_platform_data *pdata;
bool is_reading;
@@ -74,26 +78,50 @@ static inline struct jz_nand *mtd_to_jz_nand(struct mtd_info *mtd)
return container_of(mtd, struct jz_nand, mtd);
}
+static void jz_nand_select_chip(struct mtd_info *mtd, int chipnr)
+{
+ struct jz_nand *nand = mtd_to_jz_nand(mtd);
+ struct nand_chip *chip = mtd->priv;
+ uint32_t ctrl;
+ int banknr;
+
+ ctrl = readl(nand->base + JZ_REG_NAND_CTRL);
+ ctrl &= ~JZ_NAND_CTRL_ASSERT_CHIP_MASK;
+
+ if (chipnr == -1) {
+ banknr = -1;
+ } else {
+ banknr = nand->banks[chipnr] - 1;
+ chip->IO_ADDR_R = nand->bank_base[banknr];
+ chip->IO_ADDR_W = nand->bank_base[banknr];
+ }
+ writel(ctrl, nand->base + JZ_REG_NAND_CTRL);
+
+ nand->selected_bank = banknr;
+}
+
static void jz_nand_cmd_ctrl(struct mtd_info *mtd, int dat, unsigned int ctrl)
{
struct jz_nand *nand = mtd_to_jz_nand(mtd);
struct nand_chip *chip = mtd->priv;
uint32_t reg;
+ void __iomem *bank_base = nand->bank_base[nand->selected_bank];
+
+ BUG_ON(nand->selected_bank < 0);
if (ctrl & NAND_CTRL_CHANGE) {
BUG_ON((ctrl & NAND_ALE) && (ctrl & NAND_CLE));
if (ctrl & NAND_ALE)
- chip->IO_ADDR_W = nand->bank_base + JZ_NAND_MEM_ADDR_OFFSET;
+ bank_base += JZ_NAND_MEM_ADDR_OFFSET;
else if (ctrl & NAND_CLE)
- chip->IO_ADDR_W = nand->bank_base + JZ_NAND_MEM_CMD_OFFSET;
- else
- chip->IO_ADDR_W = nand->bank_base;
+ bank_base += JZ_NAND_MEM_CMD_OFFSET;
+ chip->IO_ADDR_W = bank_base;
reg = readl(nand->base + JZ_REG_NAND_CTRL);
if (ctrl & NAND_NCE)
- reg |= JZ_NAND_CTRL_ASSERT_CHIP(0);
+ reg |= JZ_NAND_CTRL_ASSERT_CHIP(nand->selected_bank);
else
- reg &= ~JZ_NAND_CTRL_ASSERT_CHIP(0);
+ reg &= ~JZ_NAND_CTRL_ASSERT_CHIP(nand->selected_bank);
writel(reg, nand->base + JZ_REG_NAND_CTRL);
}
if (dat != NAND_CMD_NONE)
@@ -252,7 +280,7 @@ static int jz_nand_correct_ecc_rs(struct mtd_info *mtd, uint8_t *dat,
}
static int jz_nand_ioremap_resource(struct platform_device *pdev,
- const char *name, struct resource **res, void __iomem **base)
+ const char *name, struct resource **res, void *__iomem *base)
{
int ret;
@@ -288,6 +316,90 @@ err:
return ret;
}
+static inline void jz_nand_iounmap_resource(struct resource *res, void __iomem *base)
+{
+ iounmap(base);
+ release_mem_region(res->start, resource_size(res));
+}
+
+static int __devinit jz_nand_detect_bank(struct platform_device *pdev, struct jz_nand *nand, unsigned char bank, size_t chipnr, uint8_t *nand_maf_id, uint8_t *nand_dev_id) {
+ int ret;
+ int gpio;
+ char gpio_name[9];
+ char res_name[6];
+ uint32_t ctrl;
+ struct mtd_info *mtd = &nand->mtd;
+ struct nand_chip *chip = &nand->chip;
+
+ /* Request GPIO port. */
+ gpio = JZ_GPIO_MEM_CS0 + bank - 1;
+ sprintf(gpio_name, "NAND CS%d", bank);
+ ret = gpio_request(gpio, gpio_name);
+ if (ret) {
+ dev_warn(&pdev->dev,
+ "Failed to request %s gpio %d: %d\n",
+ gpio_name, gpio, ret);
+ goto notfound_gpio;
+ }
+
+ /* Request I/O resource. */
+ sprintf(res_name, "bank%d", bank);
+ ret = jz_nand_ioremap_resource(pdev, res_name,
+ &nand->bank_mem[bank - 1],
+ &nand->bank_base[bank - 1]);
+ if (ret)
+ goto notfound_resource;
+
+ /* Enable chip in bank. */
+ jz_gpio_set_function(gpio, JZ_GPIO_FUNC_MEM_CS0);
+ ctrl = readl(nand->base + JZ_REG_NAND_CTRL);
+ ctrl |= JZ_NAND_CTRL_ENABLE_CHIP(bank - 1);
+ writel(ctrl, nand->base + JZ_REG_NAND_CTRL);
+
+ if (chipnr == 0) {
+ /* Detect first chip. */
+ ret = nand_scan_ident(mtd, 1, NULL);
+ if (ret)
+ goto notfound_id;
+
+ /* Retrieve the IDs from the first chip. */
+ chip->select_chip(mtd, 0);
+ chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1);
+ chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1);
+ *nand_maf_id = chip->read_byte(mtd);
+ *nand_dev_id = chip->read_byte(mtd);
+ } else {
+ /* Detect additional chip. */
+ chip->select_chip(mtd, chipnr);
+ chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1);
+ chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1);
+ if (*nand_maf_id != chip->read_byte(mtd)
+ || *nand_dev_id != chip->read_byte(mtd)) {
+ ret = -ENODEV;
+ goto notfound_id;
+ }
+
+ /* Update size of the MTD. */
+ chip->numchips++;
+ mtd->size += chip->chipsize;
+ }
+
+ dev_info(&pdev->dev, "Found chip %i on bank %i\n", chipnr, bank);
+ return 0;
+
+notfound_id:
+ dev_info(&pdev->dev, "No chip found on bank %i\n", bank);
+ ctrl &= ~(JZ_NAND_CTRL_ENABLE_CHIP(bank - 1));
+ writel(ctrl, nand->base + JZ_REG_NAND_CTRL);
+ jz_gpio_set_function(gpio, JZ_GPIO_FUNC_NONE);
+ jz_nand_iounmap_resource(nand->bank_mem[bank - 1],
+ nand->bank_base[bank - 1]);
+notfound_resource:
+ gpio_free(gpio);
+notfound_gpio:
+ return ret;
+}
+
static int __devinit jz_nand_probe(struct platform_device *pdev)
{
int ret;
@@ -295,6 +407,8 @@ static int __devinit jz_nand_probe(struct platform_device *pdev)
struct nand_chip *chip;
struct mtd_info *mtd;
struct jz_nand_platform_data *pdata = pdev->dev.platform_data;
+ size_t chipnr, bank_idx;
+ uint8_t nand_maf_id = 0, nand_dev_id = 0;
nand = kzalloc(sizeof(*nand), GFP_KERNEL);
if (!nand) {
@@ -305,10 +419,6 @@ static int __devinit jz_nand_probe(struct platform_device *pdev)
ret = jz_nand_ioremap_resource(pdev, "mmio", &nand->mem, &nand->base);
if (ret)
goto err_free;
- ret = jz_nand_ioremap_resource(pdev, "bank", &nand->bank_mem,
- &nand->bank_base);
- if (ret)
- goto err_iounmap_mmio;
if (pdata && gpio_is_valid(pdata->busy_gpio)) {
ret = gpio_request(pdata->busy_gpio, "NAND busy pin");
@@ -316,7 +426,7 @@ static int __devinit jz_nand_probe(struct platform_device *pdev)
dev_err(&pdev->dev,
"Failed to request busy gpio %d: %d\n",
pdata->busy_gpio, ret);
- goto err_iounmap_mem;
+ goto err_iounmap_mmio;
}
}
@@ -338,22 +448,51 @@ static int __devinit jz_nand_probe(struct platform_device *pdev)
chip->chip_delay = 50;
chip->cmd_ctrl = jz_nand_cmd_ctrl;
+ chip->select_chip = jz_nand_select_chip;
if (pdata && gpio_is_valid(pdata->busy_gpio))
chip->dev_ready = jz_nand_dev_ready;
- chip->IO_ADDR_R = nand->bank_base;
- chip->IO_ADDR_W = nand->bank_base;
-
nand->pdata = pdata;
platform_set_drvdata(pdev, nand);
- writel(JZ_NAND_CTRL_ENABLE_CHIP(0), nand->base + JZ_REG_NAND_CTRL);
+ /* We are going to autodetect NAND chips in the banks specified in the
+ * platform data. Although nand_scan_ident() can detect multiple chips,
+ * it requires those chips to be numbered consecuitively, which is not
+ * always the case for external memory banks. And a fixed chip-to-bank
+ * mapping is not practical either, since for example Dingoo units
+ * produced at different times have NAND chips in different banks.
+ */
+ chipnr = 0;
+ for (bank_idx = 0; bank_idx < JZ_NAND_NUM_BANKS; bank_idx++) {
+ unsigned char bank;
- ret = nand_scan_ident(mtd, 1, NULL);
- if (ret) {
- dev_err(&pdev->dev, "Failed to scan nand\n");
- goto err_gpio_free;
+ /* If there is no platform data, look for NAND in bank 1,
+ * which is the most likely bank since it is the only one
+ * that can be booted from.
+ */
+ bank = pdata ? pdata->banks[bank_idx] : bank_idx ^ 1;
+ if (bank == 0)
+ break;
+ if (bank > JZ_NAND_NUM_BANKS) {
+ dev_warn(&pdev->dev,
+ "Skipping non-existing bank: %d\n", bank);
+ continue;
+ }
+ /* The detection routine will directly or indirectly call
+ * jz_nand_select_chip(), so nand->banks has to contain the
+ * bank we're checking.
+ */
+ nand->banks[chipnr] = bank;
+ if (jz_nand_detect_bank(pdev, nand, bank, chipnr,
+ &nand_maf_id, &nand_dev_id) == 0)
+ chipnr++;
+ else
+ nand->banks[chipnr] = 0;
+ }
+ if (chipnr == 0) {
+ dev_err(&pdev->dev, "No NAND chips found\n");
+ goto err_gpio_busy;
}
if (pdata && pdata->ident_callback) {
@@ -363,8 +502,8 @@ static int __devinit jz_nand_probe(struct platform_device *pdev)
ret = nand_scan_tail(mtd);
if (ret) {
- dev_err(&pdev->dev, "Failed to scan nand\n");
- goto err_gpio_free;
+ dev_err(&pdev->dev, "Failed to scan NAND\n");
+ goto err_unclaim_banks;
}
ret = mtd_device_parse_register(mtd, NULL, 0,
@@ -381,14 +520,21 @@ static int __devinit jz_nand_probe(struct platform_device *pdev)
return 0;
err_nand_release:
- nand_release(&nand->mtd);
-err_gpio_free:
+ nand_release(mtd);
+err_unclaim_banks:
+ while (chipnr--) {
+ unsigned char bank = nand->banks[chipnr];
+ gpio_free(JZ_GPIO_MEM_CS0 + bank - 1);
+ jz_nand_iounmap_resource(nand->bank_mem[bank - 1],
+ nand->bank_base[bank - 1]);
+ }
+ writel(0, nand->base + JZ_REG_NAND_CTRL);
+err_gpio_busy:
+ if (pdata && gpio_is_valid(pdata->busy_gpio))
+ gpio_free(pdata->busy_gpio);
platform_set_drvdata(pdev, NULL);
- gpio_free(pdata->busy_gpio);
-err_iounmap_mem:
- iounmap(nand->bank_base);
err_iounmap_mmio:
- iounmap(nand->base);
+ jz_nand_iounmap_resource(nand->mem, nand->base);
err_free:
kfree(nand);
return ret;
@@ -397,16 +543,26 @@ err_free:
static int __devexit jz_nand_remove(struct platform_device *pdev)
{
struct jz_nand *nand = platform_get_drvdata(pdev);
+ struct jz_nand_platform_data *pdata = pdev->dev.platform_data;
+ size_t i;
nand_release(&nand->mtd);
/* Deassert and disable all chips */
writel(0, nand->base + JZ_REG_NAND_CTRL);
- iounmap(nand->bank_base);
- release_mem_region(nand->bank_mem->start, resource_size(nand->bank_mem));
- iounmap(nand->base);
- release_mem_region(nand->mem->start, resource_size(nand->mem));
+ for (i = 0; i < JZ_NAND_NUM_BANKS; ++i) {
+ unsigned char bank = nand->banks[i];
+ if (bank != 0) {
+ jz_nand_iounmap_resource(nand->bank_mem[bank - 1],
+ nand->bank_base[bank - 1]);
+ gpio_free(JZ_GPIO_MEM_CS0 + bank - 1);
+ }
+ }
+ if (pdata && gpio_is_valid(pdata->busy_gpio))
+ gpio_free(pdata->busy_gpio);
+
+ jz_nand_iounmap_resource(nand->mem, nand->base);
platform_set_drvdata(pdev, NULL);
kfree(nand);
--
1.7.7
