| Message ID | 1453354002-28366-6-git-send-email-wens@csie.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi, On 21-01-16 06:26, Chen-Yu Tsai wrote: > DDR transfer modes include UHS-1 DDR50 and MMC HS-DDR (or MMC_DDR52). > Consider MMC_DDR52 when setting clock delays. > > Signed-off-by: Chen-Yu Tsai <wens@csie.org> > --- > drivers/mmc/host/sunxi-mmc.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/drivers/mmc/host/sunxi-mmc.c b/drivers/mmc/host/sunxi-mmc.c > index 4bec87458317..b403a2433eec 100644 > --- a/drivers/mmc/host/sunxi-mmc.c > +++ b/drivers/mmc/host/sunxi-mmc.c > @@ -687,7 +687,8 @@ static int sunxi_mmc_clk_set_rate(struct sunxi_mmc_host *host, > oclk_dly = host->clk_delays[SDXC_CLK_25M].output; > sclk_dly = host->clk_delays[SDXC_CLK_25M].sample; > } else if (rate <= 50000000) { Shouldn't this be <= 52000000 then, considering that we may at one point get some PLL setup where we may actually be able to do 52000000 for MMC_TIMING_MMC_DDR52 ? > - if (ios->timing == MMC_TIMING_UHS_DDR50) { > + if (ios->timing == MMC_TIMING_UHS_DDR50 || > + ios->timing == MMC_TIMING_MMC_DDR52) { > oclk_dly = host->clk_delays[SDXC_CLK_50M_DDR].output; > sclk_dly = host->clk_delays[SDXC_CLK_50M_DDR].sample; > } else { > @@ -762,7 +763,8 @@ static void sunxi_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) > > /* set ddr mode */ > rval = mmc_readl(host, REG_GCTRL); > - if (ios->timing == MMC_TIMING_UHS_DDR50) > + if (ios->timing == MMC_TIMING_UHS_DDR50 || > + ios->timing == MMC_TIMING_MMC_DDR52) > rval |= SDXC_DDR_MODE; > else > rval &= ~SDXC_DDR_MODE; > Regards, Hans -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, Jan 21, 2016 at 7:14 PM, Hans de Goede <hdegoede@redhat.com> wrote: > Hi, > > On 21-01-16 06:26, Chen-Yu Tsai wrote: >> >> DDR transfer modes include UHS-1 DDR50 and MMC HS-DDR (or MMC_DDR52). >> Consider MMC_DDR52 when setting clock delays. >> >> Signed-off-by: Chen-Yu Tsai <wens@csie.org> >> --- >> drivers/mmc/host/sunxi-mmc.c | 6 ++++-- >> 1 file changed, 4 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/mmc/host/sunxi-mmc.c b/drivers/mmc/host/sunxi-mmc.c >> index 4bec87458317..b403a2433eec 100644 >> --- a/drivers/mmc/host/sunxi-mmc.c >> +++ b/drivers/mmc/host/sunxi-mmc.c >> @@ -687,7 +687,8 @@ static int sunxi_mmc_clk_set_rate(struct >> sunxi_mmc_host *host, >> oclk_dly = host->clk_delays[SDXC_CLK_25M].output; >> sclk_dly = host->clk_delays[SDXC_CLK_25M].sample; >> } else if (rate <= 50000000) { > > > Shouldn't this be <= 52000000 then, considering that we may at one point get > some PLL setup where we may actually be able to do 52000000 for > MMC_TIMING_MMC_DDR52 ? Given that mmc->f_max = 50000000, the core will never try any clock rate higher than 50 MHz, and iirc clk_round_rate always rounds down. We could increase both numbers at the same time when we actually encounter such hardware. Or we could increase both now, which I actually did in an earlier version, but it really made no difference with current hardware. Regards ChenYu > >> - if (ios->timing == MMC_TIMING_UHS_DDR50) { >> + if (ios->timing == MMC_TIMING_UHS_DDR50 || >> + ios->timing == MMC_TIMING_MMC_DDR52) { >> oclk_dly = >> host->clk_delays[SDXC_CLK_50M_DDR].output; >> sclk_dly = >> host->clk_delays[SDXC_CLK_50M_DDR].sample; >> } else { >> @@ -762,7 +763,8 @@ static void sunxi_mmc_set_ios(struct mmc_host *mmc, >> struct mmc_ios *ios) >> >> /* set ddr mode */ >> rval = mmc_readl(host, REG_GCTRL); >> - if (ios->timing == MMC_TIMING_UHS_DDR50) >> + if (ios->timing == MMC_TIMING_UHS_DDR50 || >> + ios->timing == MMC_TIMING_MMC_DDR52) >> rval |= SDXC_DDR_MODE; >> else >> rval &= ~SDXC_DDR_MODE; >> > > Regards, > > Hans -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi, On 21-01-16 12:55, Chen-Yu Tsai wrote: > On Thu, Jan 21, 2016 at 7:14 PM, Hans de Goede <hdegoede@redhat.com> wrote: >> Hi, >> >> On 21-01-16 06:26, Chen-Yu Tsai wrote: >>> >>> DDR transfer modes include UHS-1 DDR50 and MMC HS-DDR (or MMC_DDR52). >>> Consider MMC_DDR52 when setting clock delays. >>> >>> Signed-off-by: Chen-Yu Tsai <wens@csie.org> >>> --- >>> drivers/mmc/host/sunxi-mmc.c | 6 ++++-- >>> 1 file changed, 4 insertions(+), 2 deletions(-) >>> >>> diff --git a/drivers/mmc/host/sunxi-mmc.c b/drivers/mmc/host/sunxi-mmc.c >>> index 4bec87458317..b403a2433eec 100644 >>> --- a/drivers/mmc/host/sunxi-mmc.c >>> +++ b/drivers/mmc/host/sunxi-mmc.c >>> @@ -687,7 +687,8 @@ static int sunxi_mmc_clk_set_rate(struct >>> sunxi_mmc_host *host, >>> oclk_dly = host->clk_delays[SDXC_CLK_25M].output; >>> sclk_dly = host->clk_delays[SDXC_CLK_25M].sample; >>> } else if (rate <= 50000000) { >> >> >> Shouldn't this be <= 52000000 then, considering that we may at one point get >> some PLL setup where we may actually be able to do 52000000 for >> MMC_TIMING_MMC_DDR52 ? > > Given that mmc->f_max = 50000000, the core will never try any clock rate higher > than 50 MHz, and iirc clk_round_rate always rounds down. We could increase both > numbers at the same time when we actually encounter such hardware. I'm afraid that someone may increase mmc->f_max = 50000000 at one point without adjusting the rate checks above at the same time, so lets update both of them now. Regards, Hans -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/mmc/host/sunxi-mmc.c b/drivers/mmc/host/sunxi-mmc.c index 4bec87458317..b403a2433eec 100644 --- a/drivers/mmc/host/sunxi-mmc.c +++ b/drivers/mmc/host/sunxi-mmc.c @@ -687,7 +687,8 @@ static int sunxi_mmc_clk_set_rate(struct sunxi_mmc_host *host, oclk_dly = host->clk_delays[SDXC_CLK_25M].output; sclk_dly = host->clk_delays[SDXC_CLK_25M].sample; } else if (rate <= 50000000) { - if (ios->timing == MMC_TIMING_UHS_DDR50) { + if (ios->timing == MMC_TIMING_UHS_DDR50 || + ios->timing == MMC_TIMING_MMC_DDR52) { oclk_dly = host->clk_delays[SDXC_CLK_50M_DDR].output; sclk_dly = host->clk_delays[SDXC_CLK_50M_DDR].sample; } else { @@ -762,7 +763,8 @@ static void sunxi_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) /* set ddr mode */ rval = mmc_readl(host, REG_GCTRL); - if (ios->timing == MMC_TIMING_UHS_DDR50) + if (ios->timing == MMC_TIMING_UHS_DDR50 || + ios->timing == MMC_TIMING_MMC_DDR52) rval |= SDXC_DDR_MODE; else rval &= ~SDXC_DDR_MODE;
DDR transfer modes include UHS-1 DDR50 and MMC HS-DDR (or MMC_DDR52). Consider MMC_DDR52 when setting clock delays. Signed-off-by: Chen-Yu Tsai <wens@csie.org> --- drivers/mmc/host/sunxi-mmc.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)