It might be that something goes wrong during tuning so the MMC core will
immediately trigger a retune. In our case it was:
- we sent a tuning block
- there was an error so we need to send an abort cmd to the eMMC
- the abort cmd had a CRC error
- retune was set by the MMC core
This lead to a vicious circle causing a performance regression of 75%.
So, clear retuning flags before we enable retuning to start with a known
cleared state.
Reported-by Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>
Suggested-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Signed-off-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
---
drivers/mmc/core/core.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index 4e52eb14198a..f397cf051b8d 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -937,11 +937,14 @@ int mmc_execute_tuning(struct mmc_card *card)
err = host->ops->execute_tuning(host, opcode);
- if (err)
+ if (err) {
pr_err("%s: tuning execution failed: %d\n",
mmc_hostname(host), err);
- else
+ } else {
+ host->retune_now = 0;
+ host->need_retune = 0;
mmc_retune_enable(host);
+ }
return err;
}
--
2.30.2
