Re: [PATCH 2/3] scsi: ufs: initialize max_lu_supported while booting

From: asutoshd
Date: Mon Jan 13 2020 - 13:44:59 EST


On 2020-01-10 10:36, Bean Huo wrote:
From: Bean Huo <beanhuo@xxxxxxxxxx>

This patch is to add a new function ufshcd_init_device_param() for
initialization of UFS device related parameters which are used by
driver. In this version patch, there is only dev_info.max_lu_supported
being initialized.

Signed-off-by: Bean Huo <beanhuo@xxxxxxxxxx>
---
drivers/scsi/ufs/ufshcd.c | 47 ++++++++++++++++++++++++++++++++++++++-
1 file changed, 46 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 1b97f2dc0b63..a297fe55e36a 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -3158,6 +3158,11 @@ static int ufshcd_read_device_desc(struct
ufs_hba *hba, u8 *buf, u32 size)
return ufshcd_read_desc(hba, QUERY_DESC_IDN_DEVICE, 0, buf, size);
}

+static int ufshcd_read_geometry_desc(struct ufs_hba *hba, u8 *buf, u32 size)
+{
+ return ufshcd_read_desc(hba, QUERY_DESC_IDN_GEOMETRY, 0, buf, size);
+}
+
/**
* struct uc_string_id - unicode string
*
@@ -6827,6 +6832,37 @@ static void ufshcd_clear_dbg_ufs_stats(struct
ufs_hba *hba)
hba->req_abort_count = 0;
}

+static int ufshcd_init_device_param(struct ufs_hba *hba)
+{
+ int err;
+ size_t buff_len;
+ u8 *desc_buf;
+
+ buff_len = QUERY_DESC_MAX_SIZE;
+ desc_buf = kmalloc(buff_len, GFP_KERNEL);
+ if (!desc_buf) {
+ err = -ENOMEM;
+ goto out;
+ }
+
+ err = ufshcd_read_geometry_desc(hba, desc_buf,
+ hba->desc_size.geom_desc);
+ if (err) {
+ dev_err(hba->dev, "%s: Failed reading Geometry Desc. err = %d\n",
+ __func__, err);
+ goto out;
+ }
+
+ if (desc_buf[GEOMETRY_DESC_PARAM_MAX_NUM_LUN] == 1)
+ hba->dev_info.max_lu_supported = 32;
+ else if (desc_buf[GEOMETRY_DESC_PARAM_MAX_NUM_LUN] == 0)
+ hba->dev_info.max_lu_supported = 8;
+
+out:
+ kfree(desc_buf);
+ return err;
+}
+
static void ufshcd_init_desc_sizes(struct ufs_hba *hba)
{
int err;
@@ -7016,13 +7052,22 @@ static int ufshcd_probe_hba(struct ufs_hba *hba)

/*
* If we are in error handling context or in power management callbacks
- * context, no need to scan the host
+ * context, no need to scan the host and to reinitialize the parameters
*/
if (!ufshcd_eh_in_progress(hba) && !hba->pm_op_in_progress) {
bool flag;

/* clear any previous UFS device information */
memset(&hba->dev_info, 0, sizeof(hba->dev_info));
+ /* Init parameters according to UFS relevant descriptors */
+ ret = ufshcd_init_device_param(hba);
+ if (ret) {
+ dev_err(hba->dev,
+ "%s: Init of device param failed. err = %d\n",
+ __func__, ret);
+ goto out;
+ }
+
if (!ufshcd_query_flag_retry(hba, UPIU_QUERY_OPCODE_READ_FLAG,
QUERY_FLAG_IDN_PWR_ON_WPE, &flag))
hba->dev_info.f_power_on_wp_en = flag;

Looks good to me.
Reviewed-by: Asutosh Das <asutoshd@xxxxxxxxxxxxxx>