On Tue, July 17, 2012 11:16 pm, Adrian Hunter wrote:
> On 17/07/12 15:58, Jaehoon Chung wrote:
>> On 07/17/2012 09:30 PM, Adrian Hunter wrote:
>>> On 17/07/12 05:44, Jaehoon Chung wrote:
>>>
>>> <snip>
>>>
>>>> +/**
>>>> + * mmc_start_bkops - start BKOPS for supported cards
>>>> + * @card: MMC card to start BKOPS
>>>> + *
>>>> + * Start background operations whenever requested.
>>>> + * when the urgent BKOPS bit is set in a R1 command response
>>>> + * then background operations should be started immediately.
>>>> +*/
>>>> +void mmc_start_bkops(struct mmc_card *card)
>>>> +{
>>>> + int err;
>>>> + int timeout;
>>>> + u8 use_busy_signal;
>>>> +
>>>> + BUG_ON(!card);
>>>> + if (!card->ext_csd.bkops_en || !(card->host->caps2 &
>>>> MMC_CAP2_BKOPS))
>>>> + return;
>>>> +
>>>> + if (mmc_is_exception_event(card, EXT_CSD_URGENT_BKOPS))
>>>> + if (card->ext_csd.raw_bkops_status)
>>>> + mmc_card_set_need_bkops(card);
>>>> +
>>>> + /*
>>>> + * If card is already doing bkops or need for
>>>> + * bkops flag is not set, then do nothing just
>>>> + * return
>>>> + */
>>>> + if (mmc_card_doing_bkops(card) || !mmc_card_need_bkops(card))
>>>> + return;
>>>> +
>>>> + mmc_claim_host(card->host);
>>>> + if (card->ext_csd.raw_bkops_status >= EXT_CSD_BKOPS_LEVEL_2) {
>>>> + timeout = MMC_BKOPS_MAX_TIMEOUT;
>>>> + use_busy_signal = 0;
>>>> + } else {
>>>> + timeout = 0;
>>>> + use_busy_signal = 1;
>>>> + }
>>>
>>> Is this the right way around?
>>
>> use the mmc_switch() with R1B..
>> this case is no problem, because after sending bkops, repeat the
>> checking card status until prg-done.
>> But, at sdhci controller, be occurred data timeout error.
>> Because response type is r1b, and timeout value is too large.
>> (Actually, i think that is controller's problem..but just its my test
>> environment.)
>>
>> if other sdhci controller working well with R1b, use_busy_signal need
>> not.
>> Just use the mmc_switch().
>>
>> But When running bkops level2/3 use with R1 type, also no problem.
>> Because the also checking status in mmc_switch() until prg-done.
>
> You added:
>
> + /*
> + * For urgent bkops status (LEVEL_2 and more)
> + * bkops executed synchronously, otherwise
> + * the operation is in progress
> + */
> + if (card->ext_csd.raw_bkops_status < EXT_CSD_BKOPS_LEVEL_2)
> + mmc_card_set_doing_bkops(card);
>
> But:
> status < 2 => use_busy_signal = 1
> use_busy_signal = 1 => waiting
> waiting => the operation is NOT in progress
>
> Hence my question: Is this the right way around?
Good catch.
in mmc_start_bkops, use_busy_signal should be set to 1 in case
card->ext_csd.raw_bkops_status >= EXT_CSD_BKOPS_LEVEL_2
>
> Also this change is needed for the addition of 'use_busy_signal' to
> mmc_switch:
>
> diff --git a/drivers/mmc/core/mmc_ops.c b/drivers/mmc/core/mmc_ops.c
> index baf90e0..e202a5e 100644
> --- a/drivers/mmc/core/mmc_ops.c
> +++ b/drivers/mmc/core/mmc_ops.c
> @@ -417,7 +417,7 @@ int __mmc_switch(struct mmc_card *card, u8 set, u8
> index, u8 value,
> err = mmc_send_status(card, &status);
> if (err)
> return err;
> - if (card->host->caps & MMC_CAP_WAIT_WHILE_BUSY)
> + if (use_busy_signal && (card->host->caps &
> MMC_CAP_WAIT_WHILE_BUSY))
> break;
> if (mmc_host_is_spi(card->host))
> break;
>
>
--
Sent by consultant of Qualcomm Innovation Center, Inc.
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum
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