scsi: ufs: ufs-debugfs: Add user-defined exception_event_mask

Allow users to enable specific exception events via debugfs.

The bits enabled by the driver ee_drv_ctrl are separated from the bits
enabled by the user ee_usr_ctrl. The control mask ee_mask_ctrl is the
logical-or of those two. A mutex is needed to ensure that the masks match
what was written to the device.

Link: https://lore.kernel.org/r/20210209062437.6954-4-adrian.hunter@intel.com
Acked-by: Bean Huo <beanhuo@micron.com>
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/ufs/ufs-debugfs.c b/drivers/scsi/ufs/ufs-debugfs.c
index dee98dc..5972907 100644 (file)
--- a/drivers/scsi/ufs/ufs-debugfs.c
+++ b/drivers/scsi/ufs/ufs-debugfs.c
@@ -44,10 +44,56 @@ static int ufs_debugfs_stats_show(struct seq_file *s, void *data)
 }
 DEFINE_SHOW_ATTRIBUTE(ufs_debugfs_stats);
 
+static int ee_usr_mask_get(void *data, u64 *val)
+{
+       struct ufs_hba *hba = data;
+
+       *val = hba->ee_usr_mask;
+       return 0;
+}
+
+static int ufs_debugfs_get_user_access(struct ufs_hba *hba)
+__acquires(&hba->host_sem)
+{
+       down(&hba->host_sem);
+       if (!ufshcd_is_user_access_allowed(hba)) {
+               up(&hba->host_sem);
+               return -EBUSY;
+       }
+       pm_runtime_get_sync(hba->dev);
+       return 0;
+}
+
+static void ufs_debugfs_put_user_access(struct ufs_hba *hba)
+__releases(&hba->host_sem)
+{
+       pm_runtime_put_sync(hba->dev);
+       up(&hba->host_sem);
+}
+
+static int ee_usr_mask_set(void *data, u64 val)
+{
+       struct ufs_hba *hba = data;
+       int err;
+
+       if (val & ~(u64)MASK_EE_STATUS)
+               return -EINVAL;
+       err = ufs_debugfs_get_user_access(hba);
+       if (err)
+               return err;
+       err = ufshcd_update_ee_usr_mask(hba, val, MASK_EE_STATUS);
+       ufs_debugfs_put_user_access(hba);
+       return err;
+}
+
+DEFINE_DEBUGFS_ATTRIBUTE(ee_usr_mask_fops, ee_usr_mask_get, ee_usr_mask_set, "%#llx\n");
+
 void ufs_debugfs_hba_init(struct ufs_hba *hba)
 {
        hba->debugfs_root = debugfs_create_dir(dev_name(hba->dev), ufs_debugfs_root);
        debugfs_create_file("stats", 0400, hba->debugfs_root, hba, &ufs_debugfs_stats_fops);
+       debugfs_create_file("exception_event_mask", 0600, hba->debugfs_root,
+                           hba, &ee_usr_mask_fops);
 }
 
 void ufs_debugfs_hba_exit(struct ufs_hba *hba)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 98b4cc0..ac16c9a 100644 (file)
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -5162,6 +5162,46 @@ static irqreturn_t ufshcd_transfer_req_compl(struct ufs_hba *hba)
        }
 }
 
+static int __ufshcd_write_ee_control(struct ufs_hba *hba, u32 ee_ctrl_mask)
+{
+       return ufshcd_query_attr_retry(hba, UPIU_QUERY_OPCODE_WRITE_ATTR,
+                                      QUERY_ATTR_IDN_EE_CONTROL, 0, 0,
+                                      &ee_ctrl_mask);
+}
+
+static int ufshcd_write_ee_control(struct ufs_hba *hba)
+{
+       int err;
+
+       mutex_lock(&hba->ee_ctrl_mutex);
+       err = __ufshcd_write_ee_control(hba, hba->ee_ctrl_mask);
+       mutex_unlock(&hba->ee_ctrl_mutex);
+       if (err)
+               dev_err(hba->dev, "%s: failed to write ee control %d\n",
+                       __func__, err);
+       return err;
+}
+
+int ufshcd_update_ee_control(struct ufs_hba *hba, u16 *mask, u16 *other_mask,
+                            u16 set, u16 clr)
+{
+       u16 new_mask, ee_ctrl_mask;
+       int err = 0;
+
+       mutex_lock(&hba->ee_ctrl_mutex);
+       new_mask = (*mask & ~clr) | set;
+       ee_ctrl_mask = new_mask | *other_mask;
+       if (ee_ctrl_mask != hba->ee_ctrl_mask)
+               err = __ufshcd_write_ee_control(hba, ee_ctrl_mask);
+       /* Still need to update 'mask' even if 'ee_ctrl_mask' was unchanged */
+       if (!err) {
+               hba->ee_ctrl_mask = ee_ctrl_mask;
+               *mask = new_mask;
+       }
+       mutex_unlock(&hba->ee_ctrl_mutex);
+       return err;
+}
+
 /**
  * ufshcd_disable_ee - disable exception event
  * @hba: per-adapter instance
@@ -5172,22 +5212,9 @@ static irqreturn_t ufshcd_transfer_req_compl(struct ufs_hba *hba)
  *
  * Returns zero on success, non-zero error value on failure.
  */
-static int ufshcd_disable_ee(struct ufs_hba *hba, u16 mask)
+static inline int ufshcd_disable_ee(struct ufs_hba *hba, u16 mask)
 {
-       int err = 0;
-       u32 val;
-
-       if (!(hba->ee_ctrl_mask & mask))
-               goto out;
-
-       val = hba->ee_ctrl_mask & ~mask;
-       val &= MASK_EE_STATUS;
-       err = ufshcd_query_attr_retry(hba, UPIU_QUERY_OPCODE_WRITE_ATTR,
-                       QUERY_ATTR_IDN_EE_CONTROL, 0, 0, &val);
-       if (!err)
-               hba->ee_ctrl_mask &= ~mask;
-out:
-       return err;
+       return ufshcd_update_ee_drv_mask(hba, 0, mask);
 }
 
 /**
@@ -5200,22 +5227,9 @@ out:
  *
  * Returns zero on success, non-zero error value on failure.
  */
-static int ufshcd_enable_ee(struct ufs_hba *hba, u16 mask)
+static inline int ufshcd_enable_ee(struct ufs_hba *hba, u16 mask)
 {
-       int err = 0;
-       u32 val;
-
-       if (hba->ee_ctrl_mask & mask)
-               goto out;
-
-       val = hba->ee_ctrl_mask | mask;
-       val &= MASK_EE_STATUS;
-       err = ufshcd_query_attr_retry(hba, UPIU_QUERY_OPCODE_WRITE_ATTR,
-                       QUERY_ATTR_IDN_EE_CONTROL, 0, 0, &val);
-       if (!err)
-               hba->ee_ctrl_mask |= mask;
-out:
-       return err;
+       return ufshcd_update_ee_drv_mask(hba, mask, 0);
 }
 
 /**
@@ -5620,9 +5634,7 @@ static void ufshcd_exception_event_handler(struct work_struct *work)
 
        trace_ufshcd_exception_event(dev_name(hba->dev), status);
 
-       status &= hba->ee_ctrl_mask;
-
-       if (status & MASK_EE_URGENT_BKOPS)
+       if (status & hba->ee_drv_mask & MASK_EE_URGENT_BKOPS)
                ufshcd_bkops_exception_event_handler(hba);
 
 out:
@@ -7923,6 +7935,8 @@ static int ufshcd_probe_hba(struct ufs_hba *hba, bool async)
        ufshcd_set_active_icc_lvl(hba);
 
        ufshcd_wb_config(hba);
+       if (hba->ee_usr_mask)
+               ufshcd_write_ee_control(hba);
        /* Enable Auto-Hibernate if configured */
        ufshcd_auto_hibern8_enable(hba);
 
@@ -8920,6 +8934,9 @@ static int ufshcd_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
                 */
                ufshcd_urgent_bkops(hba);
 
+       if (hba->ee_usr_mask)
+               ufshcd_write_ee_control(hba);
+
        hba->clk_gating.is_suspended = false;
 
        if (ufshcd_is_clkscaling_supported(hba))
@@ -9357,6 +9374,9 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq)
        /* Initialize mutex for device management commands */
        mutex_init(&hba->dev_cmd.lock);
 
+       /* Initialize mutex for exception event control */
+       mutex_init(&hba->ee_ctrl_mutex);
+
        init_rwsem(&hba->clk_scaling_lock);
 
        ufshcd_init_clk_gating(hba);

diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index 18e56c1..9011a6d 100644 (file)
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -773,7 +773,10 @@ struct ufs_hba {
        u32 ufshcd_state;
        u32 eh_flags;
        u32 intr_mask;
-       u16 ee_ctrl_mask;
+       u16 ee_ctrl_mask; /* Exception event mask */
+       u16 ee_drv_mask;  /* Exception event mask for driver */
+       u16 ee_usr_mask;  /* Exception event mask for user (via debugfs) */
+       struct mutex ee_ctrl_mutex;
        bool is_powered;
        bool shutting_down;
        struct semaphore host_sem;
@@ -1285,4 +1288,21 @@ static inline u8 ufshcd_scsi_to_upiu_lun(unsigned int scsi_lun)
 int ufshcd_dump_regs(struct ufs_hba *hba, size_t offset, size_t len,
                     const char *prefix);
 
+int ufshcd_update_ee_control(struct ufs_hba *hba, u16 *mask, u16 *other_mask,
+                            u16 set, u16 clr);
+
+static inline int ufshcd_update_ee_drv_mask(struct ufs_hba *hba,
+                                           u16 set, u16 clr)
+{
+       return ufshcd_update_ee_control(hba, &hba->ee_drv_mask,
+                                       &hba->ee_usr_mask, set, clr);
+}
+
+static inline int ufshcd_update_ee_usr_mask(struct ufs_hba *hba,
+                                           u16 set, u16 clr)
+{
+       return ufshcd_update_ee_control(hba, &hba->ee_usr_mask,
+                                       &hba->ee_drv_mask, set, clr);
+}
+
 #endif /* End of Header */