On 31 July 2018 at 16:05, Adrian Hunter <adrian.hunter@xxxxxxxxx> wrote:
> On 31/07/18 10:04, Chunyan Zhang wrote:
>> Hi Adrian,
>>
>> On 30 July 2018 at 21:06, Adrian Hunter <adrian.hunter@xxxxxxxxx> wrote:
>>> On 23/07/18 13:08, Chunyan Zhang wrote:
>>>> As SD Host Controller Specification v4.10 documents:
>>>> Host Controller Version 4.10 defines this "Auto CMD Auto Select" mode.
>>>> Selection of Auto CMD depends on setting of CMD23 Enable in the Host
>>>> Control 2 register which indicates whether card supports CMD23. If CMD23
>>>> Enable =1, Auto CMD23 is used and if CMD23 Enable =0, Auto CMD12 is
>>>> used. In case of Version 4.10 or later, use of Auto CMD Auto Select is
>>>> recommended rather than use of Auto CMD12 Enable or Auto CMD23
>>>> Enable.
>>>>
>>>> This patch add this new mode support.
>>>>
>>>> Signed-off-by: Chunyan Zhang <zhang.chunyan@xxxxxxxxxx>
>>>> ---
>>>> drivers/mmc/host/sdhci.c | 61 +++++++++++++++++++++++++++++++++++++++---------
>>>> drivers/mmc/host/sdhci.h | 2 ++
>>>> 2 files changed, 52 insertions(+), 11 deletions(-)
>>>>
>>>> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
>>>> index 5acea3d..5c60590 100644
>>>> --- a/drivers/mmc/host/sdhci.c
>>>> +++ b/drivers/mmc/host/sdhci.c
>>>> @@ -311,6 +311,23 @@ static void sdhci_config_dma(struct sdhci_host *host)
>>>> sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL);
>>>> }
>>>>
>>>> +static void sdhci_enable_cmd23(struct sdhci_host *host)
>>>> +{
>>>> + u16 ctrl2;
>>>> +
>>>> + /*
>>>> + * This is used along with "Auto CMD Auto Select" feature,
>>>> + * which is introduced from v4.10, if card supports CMD23,
>>>> + * Auto CMD23 should be used instead of Auto CMD12.
>>>> + */
>>>> + if (host->version >= SDHCI_SPEC_410 &&
>>>> + (host->mmc->caps & MMC_CAP_CMD23)) {
>>>
>>> That is the host capability. It needs to be the card capability.
>>
>> Could you please elaborate the issue?
>>
>> I thought we're setting for host here. Do you mean we need to see the
>> card capability?
>
> Yes. SDHCI_TRNS_AUTO_SEL selects auto-CMD23 or auto-CMD12 based on this
> setting, so this must reflect the card's capability.
Got it, but how to know if the card supports CMD23?
>
>>
>>>
>>>> + ctrl2 = sdhci_readw(host, SDHCI_HOST_CONTROL2);
>>>> + ctrl2 |= SDHCI_CMD23_ENABLE;
>>>> + sdhci_writew(host, ctrl2, SDHCI_HOST_CONTROL2);
>>>> + }
>>>> +}
>>>> +
>>>> static void sdhci_init(struct sdhci_host *host, int soft)
>>>> {
>>>> struct mmc_host *mmc = host->mmc;
>>>> @@ -329,6 +346,8 @@ static void sdhci_init(struct sdhci_host *host, int soft)
>>>> host->clock = 0;
>>>> mmc->ops->set_ios(mmc, &mmc->ios);
>>>> }
>>>> +
>>>> + sdhci_enable_cmd23(host);
>>>> }
>>>>
>>>> static void sdhci_reinit(struct sdhci_host *host)
>>>> @@ -1093,6 +1112,36 @@ static inline bool sdhci_auto_cmd12(struct sdhci_host *host,
>>>> !mrq->cap_cmd_during_tfr;
>>>> }
>>>>
>>>> +static inline void sdhci_auto_cmd_select(struct sdhci_host *host,
>>>> + struct mmc_command *cmd,
>>>> + u16 *mode)
>>>> +{
>>>> + bool use_cmd12 = sdhci_auto_cmd12(host, cmd->mrq) &&
>>>> + (cmd->opcode != SD_IO_RW_EXTENDED);
>>>> + bool use_cmd23 = cmd->mrq->sbc && (host->flags & SDHCI_AUTO_CMD23);
>>>> +
>>>> + /*
>>>> + * In case of Version 4.10 or later, use of 'Auto CMD Auto
>>>> + * Select' is recommended rather than use of 'Auto CMD12
>>>> + * Enable' or 'Auto CMD23 Enable'.
>>>> + */
>>>> + if (host->version >= SDHCI_SPEC_410 && (use_cmd12 || use_cmd23)) {
>>>> + *mode |= SDHCI_TRNS_AUTO_SEL;
>>>
>>> As noted in patch 4, the CMD23 argument is not just the block count for eMMC.
>>
>> Probably I haven't got your point...
>>
>>>From what I understand, auto_sel mode doesn't need argument2. Doesn't
>> this work for eMMC?
>
> CMD23 always needs an argument
But setting argument for CMD23 will cover the block count value we set
before, that will lead mounting emmc to fail.
>
>>
>> The test platform I used was just eMMC only, haven't found problem.
>
> Because the bits that are missing from the CMD23 argument (reliable write,
> context id, etc) will not make the command fail.
>
>>
>> Thanks,
>> Chunyan
>>
>>>
>>>> + return;
>>>> + }
>>>> +
>>>> + /*
>>>> + * If we are sending CMD23, CMD12 never gets sent
>>>> + * on successful completion (so no Auto-CMD12).
>>>> + */
>>>> + if (use_cmd12) {
>>>> + *mode |= SDHCI_TRNS_AUTO_CMD12;
>>>> + } else if (use_cmd23) {
>>>> + *mode |= SDHCI_TRNS_AUTO_CMD23;
>>>> + sdhci_writel(host, cmd->mrq->sbc->arg, SDHCI_ARGUMENT2);
>>>> + }
>>>> +}
>>>> +
>>>> static void sdhci_set_transfer_mode(struct sdhci_host *host,
>>>> struct mmc_command *cmd)
>>>> {
>>>> @@ -1119,17 +1168,7 @@ static void sdhci_set_transfer_mode(struct sdhci_host *host,
>>>>
>>>> if (mmc_op_multi(cmd->opcode) || data->blocks > 1) {
>>>> mode = SDHCI_TRNS_BLK_CNT_EN | SDHCI_TRNS_MULTI;
>>>> - /*
>>>> - * If we are sending CMD23, CMD12 never gets sent
>>>> - * on successful completion (so no Auto-CMD12).
>>>> - */
>>>> - if (sdhci_auto_cmd12(host, cmd->mrq) &&
>>>> - (cmd->opcode != SD_IO_RW_EXTENDED))
>>>> - mode |= SDHCI_TRNS_AUTO_CMD12;
>>>> - else if (cmd->mrq->sbc && (host->flags & SDHCI_AUTO_CMD23)) {
>>>> - mode |= SDHCI_TRNS_AUTO_CMD23;
>>>> - sdhci_writel(host, cmd->mrq->sbc->arg, SDHCI_ARGUMENT2);
>>>> - }
>>>> + sdhci_auto_cmd_select(host, cmd, &mode);
>>>> }
>>>>
>>>> if (data->flags & MMC_DATA_READ)
>>>> diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
>>>> index 81aae07..a8f4ec2 100644
>>>> --- a/drivers/mmc/host/sdhci.h
>>>> +++ b/drivers/mmc/host/sdhci.h
>>>> @@ -42,6 +42,7 @@
>>>> #define SDHCI_TRNS_BLK_CNT_EN 0x02
>>>> #define SDHCI_TRNS_AUTO_CMD12 0x04
>>>> #define SDHCI_TRNS_AUTO_CMD23 0x08
>>>> +#define SDHCI_TRNS_AUTO_SEL 0x0C
>>>> #define SDHCI_TRNS_READ 0x10
>>>> #define SDHCI_TRNS_MULTI 0x20
>>>>
>>>> @@ -185,6 +186,7 @@
>>>> #define SDHCI_CTRL_DRV_TYPE_D 0x0030
>>>> #define SDHCI_CTRL_EXEC_TUNING 0x0040
>>>> #define SDHCI_CTRL_TUNED_CLK 0x0080
>>>> +#define SDHCI_CMD23_ENABLE 0x0800
>>>> #define SDHCI_CTRL_V4_MODE 0x1000
>>>> #define SDHCI_CTRL_64BIT_ADDR 0x2000
>>>> #define SDHCI_CTRL_PRESET_VAL_ENABLE 0x8000
>>>>
>>>
>>
>
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