Hi Ulf
On 3/6/19 10:00 AM, Ulf Hansson wrote:
On Tue, 5 Mar 2019 at 17:10, Ludovic Barre <ludovic.Barre@xxxxxx> wrote:
From: Ludovic Barre <ludovic.barre@xxxxxx>
The busy status bit could occurred even if no busy response is
expected (example cmd11). On sdmmc variant, the busy_detect_flag
reflects inverted value of d0 state, it's sampled at the end of a
CMD response and a second time 2 clk cycles after the CMD response.
To avoid a fake busy, the busy status could be checked and polled
only if the command has RSP_BUSY flag.
Signed-off-by: Ludovic Barre <ludovic.barre@xxxxxx>
Before I review this, can you tell what HW you have tested this on?
I tested on stm32mp157c (stm32_sdmmc variant)
Kind regards
Uffe
---
drivers/mmc/host/mmci.c | 19 +++++++++++++------
1 file changed, 13 insertions(+), 6 deletions(-)
diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index 387ff14..4901b73 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -1220,12 +1220,13 @@ mmci_cmd_irq(struct mmci_host *host, struct mmc_command *cmd,
unsigned int status)
{
void __iomem *base = host->base;
- bool sbc;
+ bool sbc, busy_resp;
if (!cmd)
return;
sbc = (cmd == host->mrq->sbc);
+ busy_resp = !!(cmd->flags & MMC_RSP_BUSY);
/*
* We need to be one of these interrupts to be considered worth
@@ -1239,8 +1240,7 @@ mmci_cmd_irq(struct mmci_host *host, struct mmc_command *cmd,
/*
* ST Micro variant: handle busy detection.
*/
- if (host->variant->busy_detect) {
- bool busy_resp = !!(cmd->flags & MMC_RSP_BUSY);
+ if (busy_resp && host->variant->busy_detect) {
/* We are busy with a command, return */
if (host->busy_status &&
@@ -1253,7 +1253,7 @@ mmci_cmd_irq(struct mmci_host *host, struct mmc_command *cmd,
* that the special busy status bit is still set before
* proceeding.
*/
- if (!host->busy_status && busy_resp &&
+ if (!host->busy_status &&
!(status & (MCI_CMDCRCFAIL|MCI_CMDTIMEOUT)) &&
(readl(base + MMCISTATUS) & host->variant->busy_detect_flag)) {
@@ -1508,6 +1508,7 @@ static irqreturn_t mmci_irq(int irq, void *dev_id)
{
struct mmci_host *host = dev_id;
u32 status;
+ bool busy_resp;
int ret = 0;
spin_lock(&host->lock);
@@ -1550,9 +1551,15 @@ static irqreturn_t mmci_irq(int irq, void *dev_id)
}
/*
- * Don't poll for busy completion in irq context.
+ * Don't poll for:
+ * -busy completion in irq context.
+ * -no busy response expected.
*/
- if (host->variant->busy_detect && host->busy_status)
+ busy_resp = host->cmd ?
+ !!(host->cmd->flags & MMC_RSP_BUSY) : false;
+
+ if (host->variant->busy_detect &&
+ (!busy_resp || host->busy_status))
status &= ~host->variant->busy_detect_flag;
ret = 1;
--
2.7.4
