[PATCH v1 1/5] mtd: rawnand: meson: fix NAND access for read/write

Arseniy Krasnov
2023-04-12T06:21:26Z

This fixes read/write functionality. New command sequences were ported
from old vendor's driver. Without this patch driver works unstable. This
change is tested with 'nanddump'/'nandwrite' utilities and mounting
JFFS2 filesystem on AXG family (A113X SoC).

Fixes: 8fae856c5350 ("mtd: rawnand: meson: add support for Amlogic NAND flash controller")
Signed-off-by: Arseniy Krasnov <AVKrasnov@sberdevices.ru>
---
drivers/mtd/nand/raw/meson_nand.c | 116 ++++++++++++++++++++++++++----
1 file changed, 101 insertions(+), 15 deletions(-)

diff --git a/drivers/mtd/nand/raw/meson_nand.c b/drivers/mtd/nand/raw/meson_nand.c
index 074e14225c06..256c37c76526 100644
--- a/drivers/mtd/nand/raw/meson_nand.c
+++ b/drivers/mtd/nand/raw/meson_nand.c
@@ -26,6 +26,7 @@
#define NFC_CMD_IDLE (0xc << 14)
#define NFC_CMD_CLE (0x5 << 14)
#define NFC_CMD_ALE (0x6 << 14)
+#define NFC_CMD_DRD (0x8 << 14)
#define NFC_CMD_ADL ((0 << 16) | (3 << 20))
#define NFC_CMD_ADH ((1 << 16) | (3 << 20))
#define NFC_CMD_AIL ((2 << 16) | (3 << 20))
@@ -84,6 +85,7 @@

#define DMA_BUSY_TIMEOUT 0x100000
#define CMD_FIFO_EMPTY_TIMEOUT 1000
+#define DEVICE_READY_TIMEOUT 1000

#define MAX_CE_NUM 2

@@ -255,8 +257,26 @@ static void meson_nfc_select_chip(struct nand_chip *nand, int chip)
}
}

+static int meson_nfc_wait_cmd_finish(struct meson_nfc *nfc,
+ unsigned int timeout_ms)
+{
+ u32 cmd_size = 0;
+ int ret;
+
+ /* wait cmd fifo is empty */
+ ret = readl_relaxed_poll_timeout(nfc->reg_base + NFC_REG_CMD, cmd_size,
+ !NFC_CMD_GET_SIZE(cmd_size),
+ 10, timeout_ms * 1000);
+ if (ret)
+ dev_err(nfc->dev, "wait for empty CMD FIFO timed out\n");
+
+ return ret;
+}
+
static void meson_nfc_cmd_idle(struct meson_nfc *nfc, u32 time)
{
+ meson_nfc_wait_cmd_finish(nfc, 0);
+
writel(nfc->param.chip_select | NFC_CMD_IDLE | (time & 0x3ff),
nfc->reg_base + NFC_REG_CMD);
}
@@ -308,23 +328,9 @@ static void meson_nfc_drain_cmd(struct meson_nfc *nfc)
*/
meson_nfc_cmd_idle(nfc, 0);
meson_nfc_cmd_idle(nfc, 0);
+ meson_nfc_wait_cmd_finish(nfc, 1000);
}

-static int meson_nfc_wait_cmd_finish(struct meson_nfc *nfc,
- unsigned int timeout_ms)
-{
- u32 cmd_size = 0;
- int ret;
-
- /* wait cmd fifo is empty */
- ret = readl_relaxed_poll_timeout(nfc->reg_base + NFC_REG_CMD, cmd_size,
- !NFC_CMD_GET_SIZE(cmd_size),
- 10, timeout_ms * 1000);
- if (ret)
- dev_err(nfc->dev, "wait for empty CMD FIFO time out\n");
-
- return ret;
-}

static int meson_nfc_wait_dma_finish(struct meson_nfc *nfc)
{
@@ -631,6 +637,48 @@ static int meson_nfc_rw_cmd_prepare_and_execute(struct nand_chip *nand,
return 0;
}

+static uint8_t meson_nfc_read_byte(struct nand_chip *nand)
+{
+ struct meson_nfc *nfc = nand_get_controller_data(nand);
+
+ writel(NFC_CMD_DRD, nfc->reg_base + NFC_REG_CMD);
+ meson_nfc_cmd_idle(nfc, nfc->timing.twb);
+ meson_nfc_drain_cmd(nfc);
+
+ return readl(nfc->reg_base + NFC_REG_BUF);
+}
+
+static int meson_nfc_wait_dev_ready(struct nand_chip *nand)
+{
+ struct meson_nfc *nfc = nand_get_controller_data(nand);
+ u32 cs = nfc->param.chip_select;
+ unsigned long cnt = 0;
+
+ meson_nfc_drain_cmd(nfc);
+
+ writel(cs | NFC_CMD_CLE | NAND_CMD_STATUS, nfc->reg_base + NFC_REG_CMD);
+
+ /* 10 ms. */
+ while (cnt < DEVICE_READY_TIMEOUT) {
+ uint8_t status;
+
+ status = meson_nfc_read_byte(nand);
+
+ if (status & NAND_STATUS_READY)
+ break;
+
+ usleep_range(10, 11);
+ cnt++;
+ }
+
+ if (cnt == DEVICE_READY_TIMEOUT) {
+ dev_err(nfc->dev, "device ready timeout\n");
+ return -ETIMEDOUT;
+ }
+
+ return 0;
+}
+
static int meson_nfc_write_page_sub(struct nand_chip *nand,
int page, int raw)
{
@@ -643,6 +691,10 @@ static int meson_nfc_write_page_sub(struct nand_chip *nand,
u32 cmd;
int ret;

+ ret = meson_nfc_wait_dev_ready(nand);
+ if (ret)
+ return ret;
+
meson_nfc_select_chip(nand, nand->cur_cs);

data_len = mtd->writesize + mtd->oobsize;
@@ -667,12 +719,20 @@ static int meson_nfc_write_page_sub(struct nand_chip *nand,
NFC_CMD_SCRAMBLER_DISABLE);
}

+ ret = meson_nfc_wait_dma_finish(nfc);
+ if (ret)
+ return ret;
+
cmd = nfc->param.chip_select | NFC_CMD_CLE | NAND_CMD_PAGEPROG;
writel(cmd, nfc->reg_base + NFC_REG_CMD);
meson_nfc_queue_rb(nfc, PSEC_TO_MSEC(sdr->tPROG_max));

meson_nfc_dma_buffer_release(nand, data_len, info_len, DMA_TO_DEVICE);

+ ret = meson_nfc_wait_dev_ready(nand);
+ if (ret)
+ return ret;
+
return ret;
}

@@ -720,6 +780,21 @@ static void meson_nfc_check_ecc_pages_valid(struct meson_nfc *nfc,
} while (!ret);
}

+static inline int meson_nfc_send_read(struct nand_chip *nand)
+{
+ struct meson_nfc *nfc = nand_get_controller_data(nand);
+ u32 cs = nfc->param.chip_select;
+ int ret;
+
+ ret = meson_nfc_wait_dev_ready(nand);
+ if (ret)
+ return ret;
+
+ writel(cs | NFC_CMD_CLE | NAND_CMD_READ0, nfc->reg_base + NFC_REG_CMD);
+
+ return 0;
+}
+
static int meson_nfc_read_page_sub(struct nand_chip *nand,
int page, int raw)
{
@@ -734,10 +809,18 @@ static int meson_nfc_read_page_sub(struct nand_chip *nand,
data_len = mtd->writesize + mtd->oobsize;
info_len = nand->ecc.steps * PER_INFO_BYTE;

+ ret = meson_nfc_wait_dev_ready(nand);
+ if (ret)
+ return ret;
+
ret = meson_nfc_rw_cmd_prepare_and_execute(nand, page, DIRREAD);
if (ret)
return ret;

+ ret = meson_nfc_send_read(nand);
+ if (ret)
+ return ret;
+
ret = meson_nfc_dma_buffer_setup(nand, meson_chip->data_buf,
data_len, meson_chip->info_buf,
info_len, DMA_FROM_DEVICE);
@@ -754,6 +837,9 @@ static int meson_nfc_read_page_sub(struct nand_chip *nand,
}

ret = meson_nfc_wait_dma_finish(nfc);
+ if (ret)
+ return ret;
+
meson_nfc_check_ecc_pages_valid(nfc, nand, raw);

meson_nfc_dma_buffer_release(nand, data_len, info_len, DMA_FROM_DEVICE);
--
2.35.0