On Tue, Jul 17, 2018 at 04:52:15PM +0200, Niklas Söderlund wrote: > When tuning each tap is issued CMD19 twice and the result of both runs > recorded in host->taps. If the result is different between the two runs > the wrong sampling clock position was selected. Fix this by merging the > two runs and only keep the result for each tap if it was good in both > sets. > > Signed-off-by: Niklas Söderlund <[email protected]>
Reviewed-by: Simon Horman <[email protected]> > > --- > > * Changes since v2 > - Rewrote the change to use a less clumsy loop. The patch is now > completely changed from Hayakawa-sans version and therefor I have also > claimed authorship. > - Fixed spelling in comment as suggested by Geert. > > * Changes since v1 > - Updated commit message after discussion with Wolfram. > - Expanded comment in code to better explain why the results are merged. > --- > drivers/mmc/host/renesas_sdhi_core.c | 12 ++++++++++++ > 1 file changed, 12 insertions(+) > > diff --git a/drivers/mmc/host/renesas_sdhi_core.c > b/drivers/mmc/host/renesas_sdhi_core.c > index 384ae6cfa289e22c..777e32b0e410e850 100644 > --- a/drivers/mmc/host/renesas_sdhi_core.c > +++ b/drivers/mmc/host/renesas_sdhi_core.c > @@ -384,6 +384,18 @@ static int renesas_sdhi_select_tuning(struct > tmio_mmc_host *host) > /* Clear SCC_RVSREQ */ > sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_RVSREQ, 0); > > + /* > + * When tuning CMD19 is issued twice for each tap, merge the > + * result requiring the tap to be good in both runs before > + * considering it for tuning selection. > + */ > + for (i = 0; i < host->tap_num * 2; i++) { > + int offset = host->tap_num * (i < host->tap_num ? 1 : -1); > + > + if (!test_bit(i, host->taps)) > + clear_bit(i + offset, host->taps); > + } > + > /* > * Find the longest consecutive run of successful probes. If that > * is more than SH_MOBILE_SDHI_MAX_TAP probes long then use the > -- > 2.18.0 >
