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| author | Markus Niebel <Markus.Niebel@tqs.de> | 2013-09-05 15:31:20 +0200 |
|---|---|---|
| committer | Sascha Hauer <s.hauer@pengutronix.de> | 2013-09-11 12:20:01 +0200 |
| commit | e3ab3078dca6f84c40ed39830ff351015e6b3914 (patch) | |
| tree | 0ff8e851ebd384e445bb83085ad5212feeca3be6 /drivers/mci/imx-esdhc.c | |
| parent | f0b68f0008f94606f6b927590d1fafb34b1abc55 (diff) | |
| download | barebox-e3ab3078dca6f84c40ed39830ff351015e6b3914.tar.gz barebox-e3ab3078dca6f84c40ed39830ff351015e6b3914.tar.xz | |
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>
Diffstat (limited to 'drivers/mci/imx-esdhc.c')
| -rw-r--r-- | drivers/mci/imx-esdhc.c | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/drivers/mci/imx-esdhc.c b/drivers/mci/imx-esdhc.c index 8cf3e641c1..8da7097c43 100644 --- a/drivers/mci/imx-esdhc.c +++ b/drivers/mci/imx-esdhc.c @@ -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; |