> -----Original Message----- > From: Adrian Hunter [mailto:adrian.hunter@xxxxxxxxx] > Sent: 2018年12月20日 22:01 > To: BOUGH CHEN <haibo.chen@xxxxxxx>; ulf.hansson@xxxxxxxxxx > Cc: linux-mmc@xxxxxxxxxxxxxxx; dl-linux-imx <linux-imx@xxxxxxx> > Subject: Re: [PATCH] mmc: sdhci: make DDR50 tuning optionally > > On 20/12/18 1:38 PM, BOUGH CHEN wrote: > > DDR50 tuning is optinally defined in sd 3.0 spec. For example, i.MX > > uSDHC internally already uses a fixed optimized timing for DDR50, > > normally does not require tuning for DDR50 mode. > > > > So this patch make DDR50 tuning optionally and platform can claim > > SDHCI_DDR50_NEEDS_TUNING to support if it wants tuning. > > It is optional to call sdhci_execute_tuning(). Consider > xenon_execute_tuning() for example. > Replace the sdhci_execute_tuning(), this seems to be reasonable, I will use this method and send a new patch. Thanks! Bough Chen > > > > Signed-off-by: Haibo Chen <haibo.chen@xxxxxxx> > > --- > > drivers/mmc/host/sdhci.c | 6 +++++- > > drivers/mmc/host/sdhci.h | 1 + > > 2 files changed, 6 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index > > 67e43ec..144418e 100644 > > --- a/drivers/mmc/host/sdhci.c > > +++ b/drivers/mmc/host/sdhci.c > > @@ -2429,9 +2429,13 @@ int sdhci_execute_tuning(struct mmc_host > *mmc, u32 opcode) > > break; > > > > case MMC_TIMING_UHS_SDR104: > > - case MMC_TIMING_UHS_DDR50: > > break; > > > > + case MMC_TIMING_UHS_DDR50: > > + if (host->flags & SDHCI_DDR50_NEEDS_TUNING) > > + break; > > + /* FALLTHROUGH */ > > + > > case MMC_TIMING_UHS_SDR50: > > if (host->flags & SDHCI_SDR50_NEEDS_TUNING) > > break; > > diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h index > > 6cc9a3c..58b363b 100644 > > --- a/drivers/mmc/host/sdhci.h > > +++ b/drivers/mmc/host/sdhci.h > > @@ -506,6 +506,7 @@ struct sdhci_host { > > #define SDHCI_REQ_USE_DMA (1<<2) /* Use DMA for this req. */ > > #define SDHCI_DEVICE_DEAD (1<<3) /* Device unresponsive */ > > #define SDHCI_SDR50_NEEDS_TUNING (1<<4) /* SDR50 needs tuning > */ > > +#define SDHCI_DDR50_NEEDS_TUNING (1<<5) /* DDR50 needs tuning */ > > #define SDHCI_AUTO_CMD12 (1<<6) /* Auto CMD12 support */ > > #define SDHCI_AUTO_CMD23 (1<<7) /* Auto CMD23 support */ > > #define SDHCI_PV_ENABLED (1<<8) /* Preset value enabled */ > >
