Re: [PATCH v1] ufs: introduce UFSHCD_QUIRK_BROKEN_REQ_LIST_CLR quirk

[Subhash Jadavani <subhashj@codeaurora.org>]

On 2016-11-07 23:50, Kiwoong Kim wrote:
> Some UFS host controllers may clear a transfer request slot
> by setting an associated bit in UTLRCLR/UTMLRCLR to 1, not 0.

s/UTLRCLR/UTRLCLR
s/UTMLRCLR/UTMRLCLR


> That's opposite to what UFS spec decribes.
> 
> Signed-off-by: Kiwoong Kim <kwmad.kim@samsung.com>
> ---
>  drivers/scsi/ufs/ufshcd.c | 32 ++++++++++++++++++++++++++++----
>  drivers/scsi/ufs/ufshcd.h |  1 +
>  2 files changed, 29 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
> index 549e3e8..24d6ea7 100644
> --- a/drivers/scsi/ufs/ufshcd.c
> +++ b/drivers/scsi/ufs/ufshcd.c
> @@ -392,7 +392,31 @@ static inline void ufshcd_put_tm_slot(struct
> ufs_hba *hba, int slot)
>   */
>  static inline void ufshcd_utrl_clear(struct ufs_hba *hba, u32 pos)
>  {
> -	ufshcd_writel(hba, ~(1 << pos), REG_UTP_TRANSFER_REQ_LIST_CLEAR);
> +	u32 clear;
> +
> +	if (hba->quirks & UFSHCD_QUIRK_BROKEN_REQ_LIST_CLR)
> +		clear = (1 << pos);
> +	else
> +		clear = ~(1 << pos);
> +
> +	ufshcd_writel(hba, clear, REG_UTP_TRANSFER_REQ_LIST_CLEAR);
> +}
> +
> +/**
> + * ufshcd_utmrl_clear - Clear a bit in UTRMLCLR register
> + * @hba: per adapter instance
> + * @pos: position of the bit to be cleared
> + */
> +static inline void ufshcd_utmrl_clear(struct ufs_hba *hba, u32 pos)
> +{
> +	u32 clear;
> +
> +	if (hba->quirks & UFSHCD_QUIRK_BROKEN_REQ_LIST_CLR)
> +		clear = (1 << pos);
> +	else
> +		clear = ~(1 << pos);
> +
> +	ufshcd_writel(hba, clear, REG_UTP_TASK_REQ_LIST_CLEAR);
>  }
> 
>  /**
> @@ -1147,7 +1171,7 @@ ufshcd_send_uic_cmd(struct ufs_hba *hba, struct
> uic_command *uic_cmd)
>   *
>   * Returns 0 in case of success, non-zero value in case of failure
>   */
> -static int ufshcd_map_sg(struct ufshcd_lrb *lrbp)
> +static int ufshcd_map_sg(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)

unrelated change. Please remove it.

>  {
>  	struct ufshcd_sg_entry *prd_table;
>  	struct scatterlist *sg;
> @@ -1529,7 +1553,7 @@ static int ufshcd_queuecommand(struct Scsi_Host
> *host, struct scsi_cmnd *cmd)
> 
>  	ufshcd_comp_scsi_upiu(hba, lrbp);
> 
> -	err = ufshcd_map_sg(lrbp);
> +	err = ufshcd_map_sg(hba, lrbp);

unrelated change.  Please remove it.


>  	if (err) {
>  		lrbp->cmd = NULL;
>  		clear_bit_unlock(tag, &hba->lrb_in_use);
> @@ -4329,7 +4353,7 @@ static int ufshcd_clear_tm_cmd(struct ufs_hba
> *hba, int tag)
>  		goto out;
> 
>  	spin_lock_irqsave(hba->host->host_lock, flags);
> -	ufshcd_writel(hba, ~(1 << tag), REG_UTP_TASK_REQ_LIST_CLEAR);
> +	ufshcd_utmrl_clear(hba, tag);
>  	spin_unlock_irqrestore(hba->host->host_lock, flags);
> 
>  	/* poll for max. 1 sec to clear door bell register by h/w */
> diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
> index 565f005..c4abd76 100644
> --- a/drivers/scsi/ufs/ufshcd.h
> +++ b/drivers/scsi/ufs/ufshcd.h
> @@ -495,6 +495,7 @@ struct ufs_hba {
> 
>  	#define UFSHCD_QUIRK_GET_VS_RESULT			UFS_BIT(6)
>  	#define UFSHCD_QUIRK_BROKEN_DWORD_UTRD                  UFS_BIT(7)
> +	#define UFSHCD_QUIRK_BROKEN_REQ_LIST_CLR                UFS_BIT(8)
> 
> 
>  	unsigned int quirks;	/* Deviations from standard UFSHCI spec. */

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