[PATCH V2 3/4] scsi: ufs-debugfs: Add user-defined exception_event_mask

Adrian Hunter
2021-02-09T06:32:59Z

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.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
---
drivers/scsi/ufs/ufs-debugfs.c | 46 ++++++++++++++++++
drivers/scsi/ufs/ufshcd.c | 86 +++++++++++++++++++++-------------
drivers/scsi/ufs/ufshcd.h | 22 ++++++++-
3 files changed, 120 insertions(+), 34 deletions(-)

diff --git a/drivers/scsi/ufs/ufs-debugfs.c b/drivers/scsi/ufs/ufs-debugfs.c
index dee98dc72d29..59729073b569 100644
--- 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 d6fdce655388..065a662e7886 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -5160,6 +5160,46 @@ 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
@@ -5170,22 +5210,9 @@ 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);
}

/**
@@ -5198,22 +5225,9 @@ static int ufshcd_disable_ee(struct ufs_hba *hba, u16 mask)
*
* 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);
}

/**
@@ -5618,9 +5632,7 @@ 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:
@@ -7921,6 +7933,8 @@ 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);

@@ -8918,6 +8932,9 @@ 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))
@@ -9355,6 +9372,9 @@ 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 ee61f821f75d..9b7413f35def 100644
--- 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 */
--
2.17.1