On 5/2/2013 12:49 PM, Santosh Y wrote:
-static inline void
-ufshcd_send_uic_command(struct ufs_hba *hba, struct uic_command *uic_cmnd)
+static int ufshcd_send_uic_command(struct ufs_hba *hba,
+ struct uic_command *uic_cmnd, int retries)
{
+ int err = 0;
+ unsigned long flags;
+
+ if (unlikely(mutex_trylock(&hba->uic_cmd_mutex))) {
+ mutex_unlock(&hba->uic_cmd_mutex);
+ dev_err(hba->dev, "%s: called without prepare command\n",
+ __func__);
+ BUG();
+ }
+
+retry:
+ /* check if controller is ready to accept UIC commands */
+ if (!(readl(hba->mmio_base + REG_CONTROLLER_STATUS) &
+ UIC_COMMAND_READY)) {
+ dev_err(hba->dev, "Controller not ready to accept UIC commands\n");
+ err = -EIO;
+ goto out;
+ }
+
+ init_completion(&uic_cmnd->completion);
+
+ spin_lock_irqsave(hba->host->host_lock, flags);
+
+ /* enable UIC related interrupts */
+ if (!(hba->int_enable_mask & UIC_COMMAND_COMPL)) {
+ hba->int_enable_mask |= UIC_COMMAND_COMPL;
+ ufshcd_int_config(hba, UFSHCD_INT_ENABLE);
+ }
+
No need to check if the interrupt is already enabled, it can be
directly enabled.
That would be unnecessary device access (writel) every time we send a
UIC command.
/* Write Args */
writel(uic_cmnd->argument1,
(hba->mmio_base + REG_UIC_COMMAND_ARG_1));
@@ -415,6 +491,45 @@ ufshcd_send_uic_command(struct ufs_hba *hba, struct uic_command *uic_cmnd)
/* Write UIC Cmd */
writel((uic_cmnd->command & COMMAND_OPCODE_MASK),
(hba->mmio_base + REG_UIC_COMMAND));
+
+ /* flush to make sure h/w sees the write */
+ readl(hba->mmio_base + REG_UIC_COMMAND);
+
+ spin_unlock_irqrestore(hba->host->host_lock, flags);
+
mutex lock/unlock can be done in the send_uic_command, It will
simplify the process for the caller.
ufshcd_dme_get_attr()
{
1) ufshcd_prepare_uic_command_lck();
2) ufshcd_send_uic_command();
3) Read arg3 to know the value of Uni-pro attribute.
4) ufshcd_unprepare_uic_command_unlck();
}
Step 3 above is optional for some of the UIC commands but when it is
required it should be done with mutex lock held as the
hba->active_uic_cmd might be modified by some one else before value
present hba->active_uic_cmd->argument3 is read.
But thinking more on this holding lock only in send_uic_command() is
feasible.
+ err = wait_for_completion_timeout(
+ &uic_cmnd->completion, UIC_COMMAND_TIMEOUT);
+ if (!err) {
+ err = -ETIMEDOUT;
+ } else if (uic_cmnd->argument2 & MASK_UIC_COMMAND_RESULT) {
+ /* something bad with h/w or arguments, try again */
+ if (--retries)
+ goto retry;
+
--
Regards,
Sujit
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