Re: [PATCH v5 08/15] scsi: ufs: add retries to dme_peer get and set attribute

From: Gilad Broner
Date: Tue Oct 27 2015 - 10:58:58 EST


Reviewed-by: Gilad Broner <gbroner@xxxxxxxxxxxxxx>

> The dme_peer get/set attribute commands are prone to errors, therefore
> we add three retries for the UIC command sending.
> Error code returned from ufshcd_send_uic_cmd() is checked, and unless
> it was successful or the retries have finished, another command will be
> sent.
>
> Signed-off-by: Lee Susman <lsusman@xxxxxxxxxxxxxx>
> Signed-off-by: Yaniv Gardi <ygardi@xxxxxxxxxxxxxx>
>
> ---
> drivers/scsi/ufs/ufshcd.c | 40 +++++++++++++++++++++++++++++-----------
> 1 file changed, 29 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
> index 8a04691..5005d12 100644
> --- a/drivers/scsi/ufs/ufshcd.c
> +++ b/drivers/scsi/ufs/ufshcd.c
> @@ -70,6 +70,9 @@
> /* Task management command timeout */
> #define TM_CMD_TIMEOUT 100 /* msecs */
>
> +/* maximum number of retries for a general UIC command */
> +#define UFS_UIC_COMMAND_RETRIES 3
> +
> /* maximum number of link-startup retries */
> #define DME_LINKSTARTUP_RETRIES 3
>
> @@ -2185,6 +2188,7 @@ int ufshcd_dme_set_attr(struct ufs_hba *hba, u32
> attr_sel,
> };
> const char *set = action[!!peer];
> int ret;
> + int retries = UFS_UIC_COMMAND_RETRIES;
>
> uic_cmd.command = peer ?
> UIC_CMD_DME_PEER_SET : UIC_CMD_DME_SET;
> @@ -2192,10 +2196,18 @@ int ufshcd_dme_set_attr(struct ufs_hba *hba, u32
> attr_sel,
> uic_cmd.argument2 = UIC_ARG_ATTR_TYPE(attr_set);
> uic_cmd.argument3 = mib_val;
>
> - ret = ufshcd_send_uic_cmd(hba, &uic_cmd);
> - if (ret)
> - dev_err(hba->dev, "%s: attr-id 0x%x val 0x%x error code %d\n",
> - set, UIC_GET_ATTR_ID(attr_sel), mib_val, ret);
> + do {
> + /* for peer attributes we retry upon failure */
> + ret = ufshcd_send_uic_cmd(hba, &uic_cmd);
> + if (ret)
> + dev_dbg(hba->dev, "%s: attr-id 0x%x val 0x%x error code %d\n",
> + set, UIC_GET_ATTR_ID(attr_sel), mib_val, ret);
> + } while (ret && peer && --retries);
> +
> + if (!retries)
> + dev_err(hba->dev, "%s: attr-id 0x%x val 0x%x failed %d retries\n",
> + set, UIC_GET_ATTR_ID(attr_sel), mib_val,
> + retries);
>
> return ret;
> }
> @@ -2220,6 +2232,7 @@ int ufshcd_dme_get_attr(struct ufs_hba *hba, u32
> attr_sel,
> };
> const char *get = action[!!peer];
> int ret;
> + int retries = UFS_UIC_COMMAND_RETRIES;
> struct ufs_pa_layer_attr orig_pwr_info;
> struct ufs_pa_layer_attr temp_pwr_info;
> bool pwr_mode_change = false;
> @@ -2250,14 +2263,19 @@ int ufshcd_dme_get_attr(struct ufs_hba *hba, u32
> attr_sel,
> UIC_CMD_DME_PEER_GET : UIC_CMD_DME_GET;
> uic_cmd.argument1 = attr_sel;
>
> - ret = ufshcd_send_uic_cmd(hba, &uic_cmd);
> - if (ret) {
> - dev_err(hba->dev, "%s: attr-id 0x%x error code %d\n",
> - get, UIC_GET_ATTR_ID(attr_sel), ret);
> - goto out;
> - }
> + do {
> + /* for peer attributes we retry upon failure */
> + ret = ufshcd_send_uic_cmd(hba, &uic_cmd);
> + if (ret)
> + dev_dbg(hba->dev, "%s: attr-id 0x%x error code %d\n",
> + get, UIC_GET_ATTR_ID(attr_sel), ret);
> + } while (ret && peer && --retries);
> +
> + if (!retries)
> + dev_err(hba->dev, "%s: attr-id 0x%x failed %d retries\n",
> + get, UIC_GET_ATTR_ID(attr_sel), retries);
>
> - if (mib_val)
> + if (mib_val && !ret)
> *mib_val = uic_cmd.argument3;
>
> if (peer && (hba->quirks & UFSHCD_QUIRK_DME_PEER_ACCESS_AUTO_MODE)
> --
> 1.8.5.2
>
> --
> QUALCOMM ISRAEL, on behalf of Qualcomm Innovation Center, Inc. is a member
> of Code Aurora Forum, hosted by The Linux Foundation
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--
Qualcomm Israel, on behalf of Qualcomm Innovation Center, Inc.
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project

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