On Mar 7, 2013, at 8:57 PM, Chunhe Lan wrote: > On 03/08/2013 12:30 AM, Gala Kumar-B11780 wrote: >> On Mar 7, 2013, at 2:05 AM, Chunhe Lan wrote: >> >>> This patch fixes timeout problems on t4240's sdhci controller: >>> >>> mmc0: Too large timeout requested for CMD25! >>> mmc0: Too large timeout requested for CMD25! >>> mmc0: Too large timeout requested for CMD25! >>> >>> Signed-off-by: Chunhe Lan <chunhe....@freescale.com> >>> --- >>> drivers/mmc/host/sdhci-pltfm.c | 1 + >>> 1 files changed, 1 insertions(+), 0 deletions(-) >>> >>> diff --git a/drivers/mmc/host/sdhci-pltfm.c b/drivers/mmc/host/sdhci-pltfm.c >>> index 3145a78..9db7b12 100644 >>> --- a/drivers/mmc/host/sdhci-pltfm.c >>> +++ b/drivers/mmc/host/sdhci-pltfm.c >>> @@ -94,6 +94,7 @@ void sdhci_get_of_property(struct platform_device *pdev) >>> >>> if (of_device_is_compatible(np, "fsl,p2020-esdhc") || >>> of_device_is_compatible(np, "fsl,p1010-esdhc") || >>> + of_device_is_compatible(np, "fsl,t4240-esdhc") || >>> of_device_is_compatible(np, "fsl,mpc8536-esdhc")) >>> host->quirks |= SDHCI_QUIRK_BROKEN_TIMEOUT_VAL; >>> >>> -- >>> 1.7.6.5 >>> >> >> Why does this occur? Is it a board issue? Is it a silicon issue? Is it >> due to some erratum? Why T4 only? > It would be the property of T4 hardware, and please see below the patch > which locates > the mail list of freescale: > > eSDHC: mmc:host host need long time to generate command complete interrupt > > According to Spec 2.0, command complete interrupt will generate within 150 > SD-CLK. > But this was not enough on T4240 board. So give it sufficient time to detect > command > timeout. 1000 * HZ will be enough, this value was test on all T4 board, all > worked well. > > Signed-off-by: Jerry Huang <chang-ming.hu...@freescale.com> > Signed-off-by: Haijun Zhang <haijun.zh...@freescale.com>
I still don't understand the explanation of the issue on T4. Why doesn't P4080, P5020, etc suffer from the issue? - k _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
