Re: [PATCH v2] ufs: introduce UFSHCI_QUIRK_SKIP_RESET_INTR_AGGR quirk

[Subhash Jadavani <subhashj@codeaurora.org>]

On 2016-11-15 02:57, Kiwoong Kim wrote:
> If UFS driver resets interrupt aggregation timer and counter
> when there are some pended tasks, an IO competion interrupt
> of any corresponing task may be issued.
> That would casue a command timeout.
> 
> One thing you should mind to use interrupt aggreation
> with this quirk is that the host controller should be
> able to refresh interrupt aggreation counter or timer
> in other way, such as doing it automatically when receiving
> any response.
> 
> V2

As Martin mentioned in other email, please separate this version history 
from commit text with line having "----" before the start of version 
history.
Rest all looks good but i will wait for updated patch fixing above 
before giving Reviewed-By.

> - modify the commit message
> - change the name of the quirk
> (s/ UFSHCI_QUIRK_SKIP_INTR_AGGR/UFSHCI_QUIRK_SKIP_RESET_INTR_AGGR)
> 
> Signed-off-by: Kiwoong Kim <kwmad.kim@samsung.com>
> ---
>  drivers/scsi/ufs/ufshcd.c | 3 ++-
>  drivers/scsi/ufs/ufshcd.h | 7 +++++++
>  2 files changed, 9 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
> index 8aac98f..7b62d8b 100644
> --- a/drivers/scsi/ufs/ufshcd.c
> +++ b/drivers/scsi/ufs/ufshcd.c
> @@ -3713,7 +3713,8 @@ static void ufshcd_transfer_req_compl(struct 
> ufs_hba *hba)
>  	 * false interrupt if device completes another request after 
> resetting
>  	 * aggregation and before reading the DB.
>  	 */
> -	if (ufshcd_is_intr_aggr_allowed(hba))
> +	if ((ufshcd_is_intr_aggr_allowed(hba))
> +		&& !(hba->quirks & UFSHCI_QUIRK_SKIP_RESET_INTR_AGGR))
>  		ufshcd_reset_intr_aggr(hba);
> 
>  	tr_doorbell = ufshcd_readl(hba, REG_UTP_TRANSFER_REQ_DOOR_BELL);
> diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
> index dfa17ac..d6861ed 100644
> --- a/drivers/scsi/ufs/ufshcd.h
> +++ b/drivers/scsi/ufs/ufshcd.h
> @@ -505,6 +505,13 @@ struct ufs_hba {
>  	 */
>  	#define UFSHCD_QUIRK_BROKEN_HCE				UFS_BIT(9)
> 
> +	/*
> +	 * This quirk is only not to reset interrupt aggregation logic
> +	 * in ISR. The reset can make the host controller miss an event
> +	 * of previously completed IO.
> +	 */
> +	#define UFSHCI_QUIRK_SKIP_RESET_INTR_AGGR		UFS_BIT(10)
> +
>  	unsigned int quirks;	/* Deviations from standard UFSHCI spec. */
> 
>  	/* Device deviations from standard UFS device spec. */

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