sysmo-bts
/
barebox
9
0
Fork 0
Code Releases Activity

MCI: imx-esdhc: implement workaround for errata ENGcm12360 

At least i.MX53 has errata ENGcm12360:

Occurs when a pending command which issues busy is completed.
For a command with R1b response, the proper software sequence
is to poll the DLA for R1b commands to determine busy
state completion. The DLA polling is not working properly for
the ESDHC module. This is relevant for all eSDHC ports (eSDHC1-4 ports)

DLA bit in PRSSTAT register cannot be
polled to wait for busy state completion.

Updated block guide to reflect that DLA is not applicable to detect
busy state, instead, should poll bit 24 in PRSSTAT register (DLSL[0] bit)
to check that wait busy state is over.

Signed-off-by: Markus Niebel <Markus.Niebel@tqs.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
This commit is contained in:
Markus Niebel 2013-09-05 15:31:20 +02:00 committed by Sascha Hauer
parent f0b68f0008
commit e3ab3078dc
2 changed files with 16 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

15
drivers/mci/imx-esdhc.c
View File

@ -266,6 +266,21 @@ esdhc_send_cmd(struct mci_host *mci, struct mci_cmd *cmd, struct mci_data *data)
if (irqstat & IRQSTAT_CTOE)
return -ETIMEDOUT;
/* Workaround for ESDHC errata ENGcm03648 / ENGcm12360 */
if (!data && (cmd->resp_type & MMC_RSP_BUSY)) {
/*
* Poll on DATA0 line for cmd with busy signal for
* timout / 10 usec since DLA polling can be insecure.
*/
ret = wait_on_timeout(2500 * MSECOND,
(esdhc_read32(regs + SDHCI_PRESENT_STATE) & PRSSTAT_DAT0));
if (ret) {
dev_err(host->dev, "timeout PRSSTAT_DAT0\n");
return -ETIMEDOUT;
}
}
/* Copy the response to the response buffer */
if (cmd->resp_type & MMC_RSP_136) {
u32 cmdrsp3, cmdrsp2, cmdrsp1, cmdrsp0;

1
drivers/mci/sdhci.h
View File

@ -77,6 +77,7 @@
#define IRQSTATEN_TC 0x00000002
#define IRQSTATEN_CC 0x00000001
#define PRSSTAT_DAT0 0x01000000
#define PRSSTAT_CLSL 0x00800000
#define PRSSTAT_WPSPL 0x00080000
#define PRSSTAT_CDPL 0x00040000