> Because WB performs write in SLC mode, it is difficult to use WB infinitely.
>
> Vendors can set the Lifetime limit value to the device.
> If Lifetime exceeds the limit value, the device itself can disable the WB feature.
>
> WB feature supports "bWriteBoosterBufferLifeTimeEst (IDN = 1E)" attribute.
>
> With Lifetime exceeding the limit value, the current driver continuously performs
> the following query.
>
> - Write Flag: WB_ENABLE / DISABLE
> - Read attr: Available Buffer Size
> - Read attr: Current Buffer Size
>
> This patch recognizes that WriteBooster is no longer supported by the device,
> and prevent unnecessary query issues.
>
> Signed-off-by: Jinyoung Choi <j-young.choi@xxxxxxxxxxx>
Acked-by: Avri Altman <avri.altman@xxxxxxx>
> ---
> drivers/scsi/ufs/ufs.h | 6 +++++
> drivers/scsi/ufs/ufshcd.c | 52 +++++++++++++++++++++++++++++++++++++++
> 2 files changed, 58 insertions(+)
>
> diff --git a/drivers/scsi/ufs/ufs.h b/drivers/scsi/ufs/ufs.h index
> 0bfdca3e648e..4a00c24a3209 100644
> --- a/drivers/scsi/ufs/ufs.h
> +++ b/drivers/scsi/ufs/ufs.h
> @@ -43,6 +43,12 @@
> /* WriteBooster buffer is available only for the logical unit from 0 to 7 */
> #define UFS_UPIU_MAX_WB_LUN_ID 8
>
> +/*
> + * WriteBooster buffer lifetime has a limit setted by vendor.
> + * If it is over the limit, WriteBooster feature will be disabled.
> + */
> +#define UFS_WB_EXCEED_LIFETIME 0x0B
> +
> /* Well known logical unit id in LUN field of UPIU */ enum {
> UFS_UPIU_REPORT_LUNS_WLUN = 0x81,
> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index
> 460d2b440d2e..41d85b69fa50 100644
> --- a/drivers/scsi/ufs/ufshcd.c
> +++ b/drivers/scsi/ufs/ufshcd.c
> @@ -5778,6 +5778,47 @@ static bool
> ufshcd_wb_presrv_usrspc_keep_vcc_on(struct ufs_hba *hba,
> return false;
> }
>
> +static void ufshcd_wb_force_disable(struct ufs_hba *hba) {
> + if (!(hba->quirks & UFSHCI_QUIRK_SKIP_MANUAL_WB_FLUSH_CTRL))
> + ufshcd_wb_toggle_flush(hba, false);
> +
> + ufshcd_wb_toggle_flush_during_h8(hba, false);
> + ufshcd_wb_toggle(hba, false);
> + hba->caps &= ~UFSHCD_CAP_WB_EN;
> +
> + dev_info(hba->dev, "%s: WB force disabled\n", __func__); }
> +
> +static bool ufshcd_is_wb_buf_lifetime_available(struct ufs_hba *hba) {
> + u32 lifetime;
> + int ret;
> + u8 index;
> +
> + index = ufshcd_wb_get_query_index(hba);
> + ret = ufshcd_query_attr_retry(hba, UPIU_QUERY_OPCODE_READ_ATTR,
> + QUERY_ATTR_IDN_WB_BUFF_LIFE_TIME_EST,
> + index, 0, &lifetime);
> + if (ret) {
> + dev_err(hba->dev,
> + "%s: bWriteBoosterBufferLifeTimeEst read failed %d\n",
> + __func__, ret);
> + return false;
> + }
> +
> + if (lifetime == UFS_WB_EXCEED_LIFETIME) {
> + dev_err(hba->dev, "%s: WB buf lifetime is exhausted 0x%02X\n",
> + __func__, lifetime);
> + return false;
> + }
> +
> + dev_dbg(hba->dev, "%s: WB buf lifetime is 0x%02X\n",
> + __func__, lifetime);
> +
> + return true;
> +}
> +
> static bool ufshcd_wb_need_flush(struct ufs_hba *hba) {
> int ret;
> @@ -5786,6 +5827,12 @@ static bool ufshcd_wb_need_flush(struct ufs_hba
> *hba)
>
> if (!ufshcd_is_wb_allowed(hba))
> return false;
> +
> + if (!ufshcd_is_wb_buf_lifetime_available(hba)) {
> + ufshcd_wb_force_disable(hba);
> + return false;
> + }
> +
> /*
> * The ufs device needs the vcc to be ON to flush.
> * With user-space reduction enabled, it's enough to enable flush @@ -
> 7486,6 +7533,7 @@ static void ufshcd_wb_probe(struct ufs_hba *hba, u8
> *desc_buf)
>
> if (!ufshcd_is_wb_allowed(hba))
> return;
> +
> /*
> * Probe WB only for UFS-2.2 and UFS-3.1 (and later) devices or
> * UFS devices with quirk
> UFS_DEVICE_QUIRK_SUPPORT_EXTENDED_FEATURES
> @@ -7537,6 +7585,10 @@ static void ufshcd_wb_probe(struct ufs_hba *hba,
> u8 *desc_buf)
> if (!d_lu_wb_buf_alloc)
> goto wb_disabled;
> }
> +
> + if (!ufshcd_is_wb_buf_lifetime_available(hba))
> + goto wb_disabled;
> +
> return;
>
> wb_disabled:
> --
> 2.25.1
