[PATCH v2 4/9] mtd: rawnand: jz4780: Add support for the JZ4740

Paul Cercueil
2019-02-02T23:20:14Z

Add support for probing the jz4780-nand driver on the JZ4740 SoC from
Ingenic.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
---

Changes:

v2: - Add support for the JZ4740 and not the JZ4725B: they behave the
same, and JZ4740 is fully upstream while JZ4725B is not. The
JZ4725B devicetree will then simply use the "ingenic,jz4740-nand"
compatible string.
- Fix the number of bytes for the ECC when the ECC strength is 4.
This is needed for the JZ4740, which uses Reed-Solomon instead of
BCH.

drivers/mtd/nand/raw/ingenic/jz4780_nand.c | 48 +++++++++++++++++-----
1 file changed, 37 insertions(+), 11 deletions(-)

diff --git a/drivers/mtd/nand/raw/ingenic/jz4780_nand.c b/drivers/mtd/nand/raw/ingenic/jz4780_nand.c
index 7f55358b860f..c0855fef7735 100644
--- a/drivers/mtd/nand/raw/ingenic/jz4780_nand.c
+++ b/drivers/mtd/nand/raw/ingenic/jz4780_nand.c
@@ -13,6 +13,7 @@
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_address.h>
+#include <linux/of_device.h>
#include <linux/gpio/consumer.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
@@ -26,13 +27,15 @@

#define DRV_NAME "jz4780-nand"

-#define OFFSET_DATA 0x00000000
-#define OFFSET_CMD 0x00400000
-#define OFFSET_ADDR 0x00800000
-
/* Command delay when there is no R/B pin. */
#define RB_DELAY_US 100

+struct jz_soc_info {
+ unsigned long data_offset;
+ unsigned long addr_offset;
+ unsigned long cmd_offset;
+};
+
struct jz4780_nand_cs {
unsigned int bank;
void __iomem *base;
@@ -40,6 +43,7 @@ struct jz4780_nand_cs {

struct jz4780_nand_controller {
struct device *dev;
+ const struct jz_soc_info *soc_info;
struct jz4780_bch *bch;
struct nand_controller controller;
unsigned int num_banks;
@@ -101,9 +105,9 @@ static void jz4780_nand_cmd_ctrl(struct nand_chip *chip, int cmd,
return;

if (ctrl & NAND_ALE)
- writeb(cmd, cs->base + OFFSET_ADDR);
+ writeb(cmd, cs->base + nfc->soc_info->addr_offset);
else if (ctrl & NAND_CLE)
- writeb(cmd, cs->base + OFFSET_CMD);
+ writeb(cmd, cs->base + nfc->soc_info->cmd_offset);
}

static int jz4780_nand_dev_ready(struct nand_chip *chip)
@@ -161,8 +165,13 @@ static int jz4780_nand_attach_chip(struct nand_chip *chip)
struct jz4780_nand_controller *nfc = to_jz4780_nand_controller(chip->controller);
int eccbytes;

- chip->ecc.bytes = fls((1 + 8) * chip->ecc.size) *
- (chip->ecc.strength / 8);
+ if (chip->ecc.strength == 4) {
+ /* JZ4740 uses 9 bytes of ECC to correct maximum 4 errors */
+ chip->ecc.bytes = 9;
+ } else {
+ chip->ecc.bytes = fls((1 + 8) * chip->ecc.size) *
+ (chip->ecc.strength / 8);
+ }

switch (chip->ecc.mode) {
case NAND_ECC_HW:
@@ -272,8 +281,8 @@ static int jz4780_nand_init_chip(struct platform_device *pdev,
return -ENOMEM;
mtd->dev.parent = dev;

- chip->legacy.IO_ADDR_R = cs->base + OFFSET_DATA;
- chip->legacy.IO_ADDR_W = cs->base + OFFSET_DATA;
+ chip->legacy.IO_ADDR_R = cs->base + nfc->soc_info->data_offset;
+ chip->legacy.IO_ADDR_W = cs->base + nfc->soc_info->data_offset;
chip->legacy.chip_delay = RB_DELAY_US;
chip->options = NAND_NO_SUBPAGE_WRITE;
chip->legacy.select_chip = jz4780_nand_select_chip;
@@ -353,6 +362,10 @@ static int jz4780_nand_probe(struct platform_device *pdev)
if (!nfc)
return -ENOMEM;

+ nfc->soc_info = device_get_match_data(dev);
+ if (!nfc->soc_info)
+ return -EINVAL;
+
/*
* Check for BCH HW before we call nand_scan_ident, to prevent us from
* having to call it again if the BCH driver returns -EPROBE_DEFER.
@@ -390,8 +403,21 @@ static int jz4780_nand_remove(struct platform_device *pdev)
return 0;
}

+static const struct jz_soc_info jz4740_soc_info = {
+ .data_offset = 0x00000000,
+ .cmd_offset = 0x00008000,
+ .addr_offset = 0x00010000,
+};
+
+static const struct jz_soc_info jz4780_soc_info = {
+ .data_offset = 0x00000000,
+ .cmd_offset = 0x00400000,
+ .addr_offset = 0x00800000,
+};
+
static const struct of_device_id jz4780_nand_dt_match[] = {
- { .compatible = "ingenic,jz4780-nand" },
+ { .compatible = "ingenic,jz4740-nand", .data = &jz4740_soc_info },
+ { .compatible = "ingenic,jz4780-nand", .data = &jz4780_soc_info },
{},
};
MODULE_DEVICE_TABLE(of, jz4780_nand_dt_match);
--
2.20.1