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

Liang Yang liang.yang at amlogic.com
Wed Apr 12 06:30:42 PDT 2023


Hi,

On 2023/4/12 20:03, Arseniy Krasnov wrote:
> [ EXTERNAL EMAIL ]
> 
> 
> 
> On 12.04.2023 13:24, Arseniy Krasnov wrote:
>>
>>
>> On 12.04.2023 12:37, Liang Yang wrote:
>>> Hi Arseniy,
>>>
>>> Thanks for pointing out this problem. also comment inline.
>>>
>>> On 2023/4/12 14:16, Arseniy Krasnov wrote:
>>>> [ EXTERNAL EMAIL ]
>>>>
>>>> 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 at 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;
>>>> +}
>>>> +
>>>
>>> it already calls meson_nfc_queue_rb() in meson_nfc_rw_cmd_prepare_and_execute(). Could you implements this in meson_nfc_queue_rb()? and we can use the irq method.
>>> also without Ready/Busy pin, the meson_nfc_queue_rb() should change like below:
>>>      ......
>>>      #define NFC_CMD_RB_INT    ((0xb << 10) | BIT(18))
> 
> Sorry, I can see this define as (and it is used in the driver):
> #define NFC_CMD_RB_INT          BIT(14)
> 
> in drivers/mtd/nand/raw/meson_nand.c
> 
> Which one is correct ?

we need to modify the define 'NFC_CMD_RB_INT' as ((0xb << 10) | BIT(18)).

> 
> Thanks, Arseniy
> 
>>>
>>>      meson_nfc_cmd_idle(nfc, 0);
>>>      cmd = nfc->param.chip_select | NFC_CMD_CLE | NAND_CMD_STATUS;
>>>      writel(cmd, nfc->reg_base + NFC_REG_CMD);
>>>      meson_nfc_cmd_idle(nfc, 5);
>>>      cmd = NFC_CMD_RB | NFC_CMD_RB_INT | nfc->timing.tbers_max;
>>>      writel(cmd, nfc->reg_base + NFC_REG_CMD);
>>>
>>>      ret = wait_for_completion_timeout(&nfc->completion,
>>>                        msecs_to_jiffies(timeout_ms));
>>>      if (ret == 0)
>>>          ret = -1;
>>>
>>>      writel(cs | NFC_CMD_CLE | NAND_CMD_READ0, nfc->reg_base + NFC_REG_CMD);
>>>      ......
>>>
>>
>>      
>> Thanks for reply! I'll try this code! One more question about OOB processing in this
>> driver (as You are author of it):
>>
>>     OOB size is 64 bytes, but for example if I have 1K ECC, 2 bytes user bytes and 14
>>     bytes for ECC code for each 1K. In this case I have access to only 32 bytes of OOB:
>>     2 x (2 user bytes + 14 ECC bytes). Correct me if i'm wrong, but rest of OOB (next
>>     32 bytes) become unavailable (in both raw and ECC modes) ?
>>
>> Thanks, Arseniy
>>
>>>>    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);
>>>
> 

-- 
Thanks,
Liang



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