[PATCH] scsi: ufs: Add retry flow for failed hba enabling

[Can Guo]

On 2020-11-12 13:45, Stanley Chu wrote:
> Once hba enabling is failed, add retry mechanism and in the
> meanwhile allow vendors to apply specific handlings before
> the next retry. For example, vendors can do vendor-specific
> host reset flow in variant function "ufshcd_vops_hce_enable_notify()".
> 
> Signed-off-by: Stanley Chu <stanley.chu at mediatek.com>

Reviewed-by: Can Guo <cang at codeaurora.org>

> ---
>  drivers/scsi/ufs/ufshcd.c | 14 ++++++++++----
>  1 file changed, 10 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
> index 8001bbfec5c0..9186ee01379a 100644
> --- a/drivers/scsi/ufs/ufshcd.c
> +++ b/drivers/scsi/ufs/ufshcd.c
> @@ -4328,8 +4328,10 @@ static inline void ufshcd_hba_stop(struct 
> ufs_hba *hba)
>   */
>  static int ufshcd_hba_execute_hce(struct ufs_hba *hba)
>  {
> -	int retry;
> +	int retry_outer = 3;
> +	int retry_inner;
> 
> +start:
>  	if (!ufshcd_is_hba_active(hba))
>  		/* change controller state to "reset state" */
>  		ufshcd_hba_stop(hba);
> @@ -4355,13 +4357,17 @@ static int ufshcd_hba_execute_hce(struct 
> ufs_hba *hba)
>  	ufshcd_delay_us(hba->vps->hba_enable_delay_us, 100);
> 
>  	/* wait for the host controller to complete initialization */
> -	retry = 50;
> +	retry_inner = 50;
>  	while (ufshcd_is_hba_active(hba)) {
> -		if (retry) {
> -			retry--;
> +		if (retry_inner) {
> +			retry_inner--;
>  		} else {
>  			dev_err(hba->dev,
>  				"Controller enable failed\n");
> +			if (retry_outer) {
> +				retry_outer--;
> +				goto start;
> +			}
>  			return -EIO;
>  		}
>  		usleep_range(1000, 1100);