On Fri, 2015-08-07 at 10:56 +0800, Yangbo Lu wrote: > For eSDHC(version < 2.3), the pre divider only could divide base clock > by 2 at least. Add workaround for this to avoid unexpected issue.
This works for me, I get my 50 MHz bus :) I would rather se you used the proper register than that SDHCI_SLOT_INT_STATUS hack. I replaced: temp = in_be32(host->ioaddr + SDHCI_SLOT_INT_STATUS); with temp = esdhc_readw(host, SDHCI_HOST_VERSION); which yields the same working result for me. With that change: Acked-by: Joakim Tjernlund <[email protected]> > Signed-off-by: Yangbo Lu <[email protected]> > --- > drivers/mmc/host/sdhci-of-esdhc.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/drivers/mmc/host/sdhci-of-esdhc.c > b/drivers/mmc/host/sdhci-of-esdhc.c > index 797be75..46edf2c 100644 > --- a/drivers/mmc/host/sdhci-of-esdhc.c > +++ b/drivers/mmc/host/sdhci-of-esdhc.c > @@ -208,6 +208,12 @@ static void esdhc_of_set_clock(struct sdhci_host *host, > unsigned int clock) > if (clock == 0) > return; > > + /* Workaround to start pre_div at 2 for VNN < VENDOR_V_23 */ > + temp = in_be32(host->ioaddr + SDHCI_SLOT_INT_STATUS); > + temp = (temp & SDHCI_VENDOR_VER_MASK) >> SDHCI_VENDOR_VER_SHIFT; > + if (temp < VENDOR_V_23) > + pre_div = 2; > + > /* Workaround to reduce the clock frequency for p1010 esdhc */ > if (of_find_compatible_node(NULL, NULL, "fsl,p1010-esdhc")) { > if (clock > 20000000) -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
