scsi: ufs: Introduce quirk to extend PA_HIBERN8TIME for UFS devices

Samsung UFS devices require additional time in hibern8 mode before
exiting, beyond the negotiated handshaking phase between the host and
device.  Introduce a quirk to increase the PA_HIBERN8TIME parameter by
100 µs, a value derived from experiments, to ensure a proper hibernation
process.

Signed-off-by: Manish Pandey <quic_mapa@quicinc.com>
Link: https://lore.kernel.org/r/20250411121630.21330-3-quic_mapa@quicinc.com
Reviewed-by: Bean Huo <beanhuo@micron.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index 44156041d88f20605c0d945c79ddc90a056726d3..ca2b0aae9d11ccaf79f6c002f7896eceb6198a9c 100644 (file)
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -278,6 +278,7 @@ static const struct ufs_dev_quirk ufs_fixups[] = {
          .model = UFS_ANY_MODEL,
          .quirk = UFS_DEVICE_QUIRK_DELAY_BEFORE_LPM |
                   UFS_DEVICE_QUIRK_HOST_PA_TACTIVATE |
+                  UFS_DEVICE_QUIRK_PA_HIBER8TIME |
                   UFS_DEVICE_QUIRK_RECOVERY_FROM_DL_NAC_ERRORS },
        { .wmanufacturerid = UFS_VENDOR_SKHYNIX,
          .model = UFS_ANY_MODEL,
@@ -8470,6 +8471,31 @@ out:
        return ret;
 }
 
+/**
+ * ufshcd_quirk_override_pa_h8time - Ensures proper adjustment of PA_HIBERN8TIME.
+ * @hba: per-adapter instance
+ *
+ * Some UFS devices require specific adjustments to the PA_HIBERN8TIME parameter
+ * to ensure proper hibernation timing. This function retrieves the current
+ * PA_HIBERN8TIME value and increments it by 100us.
+ */
+static void ufshcd_quirk_override_pa_h8time(struct ufs_hba *hba)
+{
+       u32 pa_h8time;
+       int ret;
+
+       ret = ufshcd_dme_get(hba, UIC_ARG_MIB(PA_HIBERN8TIME), &pa_h8time);
+       if (ret) {
+               dev_err(hba->dev, "Failed to get PA_HIBERN8TIME: %d\n", ret);
+               return;
+       }
+
+       /* Increment by 1 to increase hibernation time by 100 µs */
+       ret = ufshcd_dme_set(hba, UIC_ARG_MIB(PA_HIBERN8TIME), pa_h8time + 1);
+       if (ret)
+               dev_err(hba->dev, "Failed updating PA_HIBERN8TIME: %d\n", ret);
+}
+
 static void ufshcd_tune_unipro_params(struct ufs_hba *hba)
 {
        ufshcd_vops_apply_dev_quirks(hba);
@@ -8480,6 +8506,9 @@ static void ufshcd_tune_unipro_params(struct ufs_hba *hba)
 
        if (hba->dev_quirks & UFS_DEVICE_QUIRK_HOST_PA_TACTIVATE)
                ufshcd_quirk_tune_host_pa_tactivate(hba);
+
+       if (hba->dev_quirks & UFS_DEVICE_QUIRK_PA_HIBER8TIME)
+               ufshcd_quirk_override_pa_h8time(hba);
 }
 
 static void ufshcd_clear_dbg_ufs_stats(struct ufs_hba *hba)

diff --git a/include/ufs/ufs_quirks.h b/include/ufs/ufs_quirks.h
index 41ff44dfa1db3f293d16d8c917effcf6ef5bd792..f52de5ed1b3b6ebf7475d5cd42b6cb9967278d26 100644 (file)
--- a/include/ufs/ufs_quirks.h
+++ b/include/ufs/ufs_quirks.h
@@ -107,4 +107,10 @@ struct ufs_dev_quirk {
  */
 #define UFS_DEVICE_QUIRK_DELAY_AFTER_LPM        (1 << 11)
 
+/*
+ * Some ufs devices may need more time to be in hibern8 before exiting.
+ * Enable this quirk to give it an additional 100us.
+ */
+#define UFS_DEVICE_QUIRK_PA_HIBER8TIME          (1 << 12)
+
 #endif /* UFS_QUIRKS_H_ */