The card timing and the bus frequency are not changed atomically with
respect to calls to the set_clock() callback in the driver. The result
is the driver sees a transient state where there's a mismatch between
the two and thus the inputs to the phase correction calculation
formula are garbage.
Switch from dev_warn() to dev_dbg() to avoid noise in the normal case,
though the change does make bad configurations less likely to be
noticed.
Reported-by: Joel Stanley <[email protected]>
Signed-off-by: Andrew Jeffery <[email protected]>
---
drivers/mmc/host/sdhci-of-aspeed.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/mmc/host/sdhci-of-aspeed.c b/drivers/mmc/host/sdhci-of-aspeed.c
index d001c51074a0..e4665a438ec5 100644
--- a/drivers/mmc/host/sdhci-of-aspeed.c
+++ b/drivers/mmc/host/sdhci-of-aspeed.c
@@ -150,7 +150,7 @@ static int aspeed_sdhci_phase_to_tap(struct device *dev, unsigned long rate_hz,
tap = div_u64(phase_period_ps, prop_delay_ps);
if (tap > ASPEED_SDHCI_NR_TAPS) {
- dev_warn(dev,
+ dev_dbg(dev,
"Requested out of range phase tap %d for %d degrees of phase compensation at %luHz, clamping to tap %d\n",
tap, phase_deg, rate_hz, ASPEED_SDHCI_NR_TAPS);
tap = ASPEED_SDHCI_NR_TAPS;
--
2.30.2
On Mon, 7 Jun 2021 at 01:30, Andrew Jeffery <[email protected]> wrote:
>
> The card timing and the bus frequency are not changed atomically with
> respect to calls to the set_clock() callback in the driver. The result
> is the driver sees a transient state where there's a mismatch between
> the two and thus the inputs to the phase correction calculation
> formula are garbage.
>
> Switch from dev_warn() to dev_dbg() to avoid noise in the normal case,
> though the change does make bad configurations less likely to be
> noticed.
>
> Reported-by: Joel Stanley <[email protected]>
> Signed-off-by: Andrew Jeffery <[email protected]>
Reviewed-by: Joel Stanley <[email protected]>
> ---
> drivers/mmc/host/sdhci-of-aspeed.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/mmc/host/sdhci-of-aspeed.c b/drivers/mmc/host/sdhci-of-aspeed.c
> index d001c51074a0..e4665a438ec5 100644
> --- a/drivers/mmc/host/sdhci-of-aspeed.c
> +++ b/drivers/mmc/host/sdhci-of-aspeed.c
> @@ -150,7 +150,7 @@ static int aspeed_sdhci_phase_to_tap(struct device *dev, unsigned long rate_hz,
>
> tap = div_u64(phase_period_ps, prop_delay_ps);
> if (tap > ASPEED_SDHCI_NR_TAPS) {
> - dev_warn(dev,
> + dev_dbg(dev,
> "Requested out of range phase tap %d for %d degrees of phase compensation at %luHz, clamping to tap %d\n",
> tap, phase_deg, rate_hz, ASPEED_SDHCI_NR_TAPS);
> tap = ASPEED_SDHCI_NR_TAPS;
> --
> 2.30.2
>
On Mon, 7 Jun 2021 at 03:30, Andrew Jeffery <[email protected]> wrote:
>
> The card timing and the bus frequency are not changed atomically with
> respect to calls to the set_clock() callback in the driver. The result
> is the driver sees a transient state where there's a mismatch between
> the two and thus the inputs to the phase correction calculation
> formula are garbage.
>
> Switch from dev_warn() to dev_dbg() to avoid noise in the normal case,
> though the change does make bad configurations less likely to be
> noticed.
>
> Reported-by: Joel Stanley <[email protected]>
> Signed-off-by: Andrew Jeffery <[email protected]>
Applied for next, thanks!
Kind regards
Uffe
> ---
> drivers/mmc/host/sdhci-of-aspeed.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/mmc/host/sdhci-of-aspeed.c b/drivers/mmc/host/sdhci-of-aspeed.c
> index d001c51074a0..e4665a438ec5 100644
> --- a/drivers/mmc/host/sdhci-of-aspeed.c
> +++ b/drivers/mmc/host/sdhci-of-aspeed.c
> @@ -150,7 +150,7 @@ static int aspeed_sdhci_phase_to_tap(struct device *dev, unsigned long rate_hz,
>
> tap = div_u64(phase_period_ps, prop_delay_ps);
> if (tap > ASPEED_SDHCI_NR_TAPS) {
> - dev_warn(dev,
> + dev_dbg(dev,
> "Requested out of range phase tap %d for %d degrees of phase compensation at %luHz, clamping to tap %d\n",
> tap, phase_deg, rate_hz, ASPEED_SDHCI_NR_TAPS);
> tap = ASPEED_SDHCI_NR_TAPS;
> --
> 2.30.2
>