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authorLee Leahy <leroy.p.leahy@intel.com>2017-05-11 14:51:25 -0700
committerLee Leahy <leroy.p.leahy@intel.com>2017-05-12 18:20:08 +0200
commitf542aca0908ead68314a6d9603dde8849abcff19 (patch)
tree778ddd24e4ea3b5ca888ee1826b0dd153df9dba0
parent77231330739962e4a76ae23f42a840558a0c675f (diff)
downloadcoreboot-f542aca0908ead68314a6d9603dde8849abcff19.tar.xz
drivers/storage: Delay after SD SWITCH operations
Delay for a while after the switch operations to let the card recover. TEST=Build and run on Galileo Gen2 Change-Id: I938e227a142e43ed6afda80d56af90df0bae1b05 Signed-off-by: Lee Leahy <Leroy.P.Leahy@intel.com> Reviewed-on: https://review.coreboot.org/19671 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Patrick Georgi <pgeorgi@google.com>
-rw-r--r--src/drivers/storage/sd.c13
1 files changed, 13 insertions, 0 deletions
diff --git a/src/drivers/storage/sd.c b/src/drivers/storage/sd.c
index 18d2c0e245..6f4887a1a1 100644
--- a/src/drivers/storage/sd.c
+++ b/src/drivers/storage/sd.c
@@ -136,6 +136,7 @@ static void sd_recalculate_clock(struct storage_media *media)
int sd_change_freq(struct storage_media *media)
{
+ int delay;
int err, timeout;
struct mmc_command cmd;
struct sd_mmc_ctrlr *ctrlr = media->ctrlr;
@@ -225,11 +226,23 @@ int sd_change_freq(struct storage_media *media)
if (!((ctrlr->caps & DRVR_CAP_HS52) && (ctrlr->caps & DRVR_CAP_HS)))
goto out;
+ /* Give the card time to recover afer the switch operation. Wait for
+ * 9 (>= 8) clock cycles receiving the switch status.
+ */
+ delay = (9000000 + ctrlr->bus_hz - 1) / ctrlr->bus_hz;
+ udelay(delay);
+
+ /* Switch to high speed */
err = sd_switch(ctrlr, SD_SWITCH_SWITCH, 0, 1,
(uint8_t *)switch_status);
if (err)
return err;
+ /* Give the card time to perform the switch operation. Wait for 9
+ * (>= 8) clock cycles receiving the switch status.
+ */
+ udelay(delay);
+
if ((ntohl(switch_status[4]) & 0x0f000000) == 0x01000000) {
media->caps |= DRVR_CAP_HS;
SET_TIMING(ctrlr, BUS_TIMING_SD_HS);