The MMCISTATUS register is read from the IRQ handler, mmci_irq(). For
processing, its value is then passed as an in-parameter to mmci_cmd_irq().
When dealing with busy detection, the MMCISTATUS register is being re-read,
as to retrieve an updated value. However, this operation is likely costing
more than it benefits, as the value was read only a few cycles ago. For
this reason, let's simply drop the re-read and use the value from the
in-parameter instead.
Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
---
drivers/mmc/host/mmci.c | 8 +++-----
1 file changed, 3 insertions(+), 5 deletions(-)
diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index 356833a606d5..5f35afc4dbf9 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -1233,14 +1233,12 @@ mmci_cmd_irq(struct mmci_host *host, struct mmc_command *cmd,
return;
/*
- * We were not busy, but we now got a busy response on
- * something that was not an error, and we double-check
- * that the special busy status bit is still set before
- * proceeding.
+ * Before unmasking for the busy end IRQ, confirm that the
+ * command was sent successfully.
*/
if (!host->busy_status &&
!(status & (MCI_CMDCRCFAIL|MCI_CMDTIMEOUT)) &&
- (readl(base + MMCISTATUS) & host->variant->busy_detect_flag)) {
+ (status & host->variant->busy_detect_flag)) {
/* Clear the busy start IRQ */
writel(host->variant->busy_detect_mask,
--
2.17.1
