On 04.07.2023 16:07, Arseniy Krasnov wrote:
>
>
> On 04.07.2023 16:12, Miquel Raynal wrote:
>> Hi Arseniy,
>>
>> avkrasnov@xxxxxxxxxxxxxx wrote on Tue, 4 Jul 2023 15:46:18 +0300:
>>
>>> On 04.07.2023 15:43, Miquel Raynal wrote:
>>>> Hi Arseniy,
>>>>
>>>> AVKrasnov@xxxxxxxxxxxxxx wrote on Thu, 8 Jun 2023 07:47:28 +0300:
>>>>
>>>>> If there is no wired ready/busy pin, classic way to wait for command
>>>>> completion is to use function 'nand_soft_waitrdy()'. Meson NAND has
>>>>> special command which allows to wait for NAND_STATUS_READY bit without
>>>>> reading status in a software loop (as 'nand_soft_waitrdy()' does). To
>>>>> use it send this command along with NAND_CMD_STATUS, then wait for an
>>>>> interrupt, and after interrupt send NAND_CMD_READ0. So this feature
>>>>> allows to use interrupt driven waiting without wired ready/busy pin.
>>>>>
>>>>> Suggested-by: Liang Yang <liang.yang@xxxxxxxxxxx>
>>>>> Signed-off-by: Arseniy Krasnov <AVKrasnov@xxxxxxxxxxxxxx>
>>>>> ---
>>>>> drivers/mtd/nand/raw/meson_nand.c | 77 +++++++++++++++++++++++++++++--
>>>>> 1 file changed, 73 insertions(+), 4 deletions(-)
>>>>>
>>>>> diff --git a/drivers/mtd/nand/raw/meson_nand.c b/drivers/mtd/nand/raw/meson_nand.c
>>>>> index 074e14225c06..9f05e113b4ea 100644
>>>>> --- a/drivers/mtd/nand/raw/meson_nand.c
>>>>> +++ b/drivers/mtd/nand/raw/meson_nand.c
>>>>> @@ -38,6 +38,7 @@
>>>>> #define NFC_CMD_SCRAMBLER_DISABLE 0
>>>>> #define NFC_CMD_SHORTMODE_DISABLE 0
>>>>> #define NFC_CMD_RB_INT BIT(14)
>>>>> +#define NFC_CMD_RB_INT_NO_PIN ((0xb << 10) | BIT(18) | BIT(16))
>>>>>
>>>>> #define NFC_CMD_GET_SIZE(x) (((x) >> 22) & GENMASK(4, 0))
>>>>>
>>>>> @@ -179,6 +180,7 @@ struct meson_nfc {
>>>>> u32 info_bytes;
>>>>>
>>>>> unsigned long assigned_cs;
>>>>> + bool no_rb_pin;
>>>>> };
>>>>>
>>>>> enum {
>>>>> @@ -392,7 +394,42 @@ static void meson_nfc_set_data_oob(struct nand_chip *nand,
>>>>> }
>>>>> }
>>>>>
>>>>> -static int meson_nfc_queue_rb(struct meson_nfc *nfc, int timeout_ms)
>>>>> +static int meson_nfc_wait_no_rb_pin(struct meson_nfc *nfc, int timeout_ms,
>>>>> + bool need_cmd_read0)
>>>>> +{
>>>>> + u32 cmd, cfg;
>>>>> +
>>>>> + meson_nfc_cmd_idle(nfc, nfc->timing.twb);
>>>>> + meson_nfc_drain_cmd(nfc);
>>>>> + meson_nfc_wait_cmd_finish(nfc, CMD_FIFO_EMPTY_TIMEOUT);
>>>>> +
>>>>> + cfg = readl(nfc->reg_base + NFC_REG_CFG);
>>>>> + cfg |= NFC_RB_IRQ_EN;
>>>>> + writel(cfg, nfc->reg_base + NFC_REG_CFG);
>>>>> +
>>>>> + reinit_completion(&nfc->completion);
>>>>> + cmd = nfc->param.chip_select | NFC_CMD_CLE | NAND_CMD_STATUS;
>>>>> + writel(cmd, nfc->reg_base + NFC_REG_CMD);
>>>>> +
>>>>> + /* use the max erase time as the maximum clock for waiting R/B */
>>>>> + cmd = NFC_CMD_RB | NFC_CMD_RB_INT_NO_PIN | nfc->timing.tbers_max;
>>>>> + writel(cmd, nfc->reg_base + NFC_REG_CMD);
>>>>> +
>>>>> + if (!wait_for_completion_timeout(&nfc->completion,
>>>>> + msecs_to_jiffies(timeout_ms)))
>>>>> + return -ETIMEDOUT;
>>>>> +
>>>>> + if (need_cmd_read0) {
>>>>> + cmd = nfc->param.chip_select | NFC_CMD_CLE | NAND_CMD_READ0;
>>>>> + writel(cmd, nfc->reg_base + NFC_REG_CMD);
>>>>> + meson_nfc_drain_cmd(nfc);
>>>>> + meson_nfc_wait_cmd_finish(nfc, CMD_FIFO_EMPTY_TIMEOUT);
>>>>> + }
>>>>
>>>> I forgot about this, you should avoid open coding core helpers, can you
>>>> please send a followup patch to use nand_status_op() and
>>>> nand_exit_status_op() ?
>>>
>>> A ok, so:
>>> 1) Sending NAND_CMD_STATUS goes to nand_status_op()
>>> 2) Sending NAND_CMD_READ0 goes to nand_exit_status_op()
>>>
>>> Ok, no problem! I'll prepare and send it on this week!
>>
>> Exactly. Sorry I had this in mind but I likely forgot to write it
>> down.
>
> Ok, got it!
Hm, seems 'int nand_exit_status_op(struct nand_chip *chip)' is not exported,
so I can't use it in the Meson module. While 'nand_status_op()' works ok.
May I can export 'nand_exit_status_op()?'
Thanks, Arseniy
>
> Thanks, Arseniy
>
>>
>> Thanks,
>> Miquèl
