[PATCH 1/3] mmc: sdhci: Tuning should not change max_blk_count

Adrian Hunter
2014-12-01T13:19:52Z

Re-tuning requires that the maximum data length
is limited to 4MiB. The code currently changes
max_blk_count in an attempt to achieve that.
This is wrong because max_blk_count is a different
limit, but it is also un-necessary because
max_req_size is 512KiB anyway. Consequently, the
changes to max_blk_count are removed and the
comment for max_req_size adjusted accordingly.
The comment is also tweaked to show that the 512KiB
limit is a SDMA limit not an ADMA limit.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
---
drivers/mmc/host/sdhci.c | 9 +++------
1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 73de62a..b3d68e0 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -259,8 +259,6 @@ static void sdhci_reinit(struct sdhci_host *host)

del_timer_sync(&host->tuning_timer);
host->flags &= ~SDHCI_NEEDS_RETUNING;
- host->mmc->max_blk_count =
- (host->quirks & SDHCI_QUIRK_NO_MULTIBLOCK) ? 1 : 65535;
}
sdhci_enable_card_detection(host);
}
@@ -2048,8 +2046,6 @@ out:
host->flags |= SDHCI_USING_RETUNING_TIMER;
mod_timer(&host->tuning_timer, jiffies +
host->tuning_count * HZ);
- /* Tuning mode 1 limits the maximum data length to 4MB */
- mmc->max_blk_count = (4 * 1024 * 1024) / mmc->max_blk_size;
} else if (host->flags & SDHCI_USING_RETUNING_TIMER) {
host->flags &= ~SDHCI_NEEDS_RETUNING;
/* Reload the new initial value for timer */
@@ -3263,8 +3259,9 @@ int sdhci_add_host(struct sdhci_host *host)
mmc->max_segs = SDHCI_MAX_SEGS;

/*
- * Maximum number of sectors in one transfer. Limited by DMA boundary
- * size (512KiB).
+ * Maximum number of sectors in one transfer. Limited by SDMA boundary
+ * size (512KiB). Note some tuning modes impose a 4MiB limit, but this
+ * is less anyway.
*/
mmc->max_req_size = 524288;

--
1.9.1