Message ID | 20240822212418.982927-3-detlev.casanova@collabora.com (mailing list archive) |
---|---|
State | New |
Headers | show |
Series | Add dw_mmc support for rk3576 | expand |
Hello Detlev, Please see a comment below. On 2024-08-22 23:15, Detlev Casanova wrote: > From: Shawn Lin <shawn.lin@rock-chips.com> > > Some Rockchip devices put the phase settings into the dw_mmc > controller. > > When the feature is present, the ciu-drive and ciu-sample clocks are > not used and the phase configuration is done directly through the mmc > controller. > > Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com> > Signed-off-by: Detlev Casanova <detlev.casanova@collabora.com> > Acked-by: Shawn Lin <shawn.lin@rock-chips.com> > --- > drivers/mmc/host/dw_mmc-rockchip.c | 171 +++++++++++++++++++++++++++-- > 1 file changed, 160 insertions(+), 11 deletions(-) > > diff --git a/drivers/mmc/host/dw_mmc-rockchip.c > b/drivers/mmc/host/dw_mmc-rockchip.c > index b07190ba4b7a..2748f9bf2691 100644 > --- a/drivers/mmc/host/dw_mmc-rockchip.c > +++ b/drivers/mmc/host/dw_mmc-rockchip.c > @@ -15,7 +15,17 @@ > #include "dw_mmc.h" > #include "dw_mmc-pltfm.h" > > -#define RK3288_CLKGEN_DIV 2 > +#define RK3288_CLKGEN_DIV 2 > +#define SDMMC_TIMING_CON0 0x130 > +#define SDMMC_TIMING_CON1 0x134 > +#define ROCKCHIP_MMC_DELAY_SEL BIT(10) > +#define ROCKCHIP_MMC_DEGREE_MASK 0x3 > +#define ROCKCHIP_MMC_DEGREE_OFFSET 1 > +#define ROCKCHIP_MMC_DELAYNUM_OFFSET 2 > +#define ROCKCHIP_MMC_DELAYNUM_MASK (0xff << > ROCKCHIP_MMC_DELAYNUM_OFFSET) > +#define ROCKCHIP_MMC_DELAY_ELEMENT_PSEC 60 > +#define HIWORD_UPDATE(val, mask, shift) \ > + ((val) << (shift) | (mask) << ((shift) + 16)) > > static const unsigned int freqs[] = { 100000, 200000, 300000, 400000 > }; > > @@ -24,8 +34,143 @@ struct dw_mci_rockchip_priv_data { > struct clk *sample_clk; > int default_sample_phase; > int num_phases; > + int internal_phase; > }; It might be good to declare internal_phase as "unsigned int internal_phase:1", i.e. as a bit field, which isn't going to save some memory in this particular case, but it would show additional attention to detail.
Hi Dragan, On Friday, 23 August 2024 01:41:44 EDT Dragan Simic wrote: > Hello Detlev, > > Please see a comment below. > > On 2024-08-22 23:15, Detlev Casanova wrote: > > From: Shawn Lin <shawn.lin@rock-chips.com> > > > > Some Rockchip devices put the phase settings into the dw_mmc > > controller. > > > > When the feature is present, the ciu-drive and ciu-sample clocks are > > not used and the phase configuration is done directly through the mmc > > controller. > > > > Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com> > > Signed-off-by: Detlev Casanova <detlev.casanova@collabora.com> > > Acked-by: Shawn Lin <shawn.lin@rock-chips.com> > > --- > > > > drivers/mmc/host/dw_mmc-rockchip.c | 171 +++++++++++++++++++++++++++-- > > 1 file changed, 160 insertions(+), 11 deletions(-) > > > > diff --git a/drivers/mmc/host/dw_mmc-rockchip.c > > b/drivers/mmc/host/dw_mmc-rockchip.c > > index b07190ba4b7a..2748f9bf2691 100644 > > --- a/drivers/mmc/host/dw_mmc-rockchip.c > > +++ b/drivers/mmc/host/dw_mmc-rockchip.c > > @@ -15,7 +15,17 @@ > > > > #include "dw_mmc.h" > > #include "dw_mmc-pltfm.h" > > > > -#define RK3288_CLKGEN_DIV 2 > > +#define RK3288_CLKGEN_DIV 2 > > +#define SDMMC_TIMING_CON0 0x130 > > +#define SDMMC_TIMING_CON1 0x134 > > +#define ROCKCHIP_MMC_DELAY_SEL BIT(10) > > +#define ROCKCHIP_MMC_DEGREE_MASK 0x3 > > +#define ROCKCHIP_MMC_DEGREE_OFFSET 1 > > +#define ROCKCHIP_MMC_DELAYNUM_OFFSET 2 > > +#define ROCKCHIP_MMC_DELAYNUM_MASK (0xff << > > ROCKCHIP_MMC_DELAYNUM_OFFSET) > > +#define ROCKCHIP_MMC_DELAY_ELEMENT_PSEC 60 > > +#define HIWORD_UPDATE(val, mask, shift) \ > > + ((val) << (shift) | (mask) << ((shift) + 16)) > > > > static const unsigned int freqs[] = { 100000, 200000, 300000, 400000 > > > > }; > > > > @@ -24,8 +34,143 @@ struct dw_mci_rockchip_priv_data { > > > > struct clk *sample_clk; > > int default_sample_phase; > > int num_phases; > > > > + int internal_phase; > > > > }; > > It might be good to declare internal_phase as "unsigned int > internal_phase:1", > i.e. as a bit field, which isn't going to save some memory in this > particular > case, but it would show additional attention to detail. In that case, I would go with a bool instead of int, that makes things even clearer.
Hello Detlev, On 2024-08-23 15:34, Detlev Casanova wrote: > On Friday, 23 August 2024 01:41:44 EDT Dragan Simic wrote: >> Hello Detlev, >> >> Please see a comment below. >> >> On 2024-08-22 23:15, Detlev Casanova wrote: >> > From: Shawn Lin <shawn.lin@rock-chips.com> >> > >> > Some Rockchip devices put the phase settings into the dw_mmc >> > controller. >> > >> > When the feature is present, the ciu-drive and ciu-sample clocks are >> > not used and the phase configuration is done directly through the mmc >> > controller. >> > >> > Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com> >> > Signed-off-by: Detlev Casanova <detlev.casanova@collabora.com> >> > Acked-by: Shawn Lin <shawn.lin@rock-chips.com> >> > --- >> > >> > drivers/mmc/host/dw_mmc-rockchip.c | 171 +++++++++++++++++++++++++++-- >> > 1 file changed, 160 insertions(+), 11 deletions(-) >> > >> > diff --git a/drivers/mmc/host/dw_mmc-rockchip.c >> > b/drivers/mmc/host/dw_mmc-rockchip.c >> > index b07190ba4b7a..2748f9bf2691 100644 >> > --- a/drivers/mmc/host/dw_mmc-rockchip.c >> > +++ b/drivers/mmc/host/dw_mmc-rockchip.c >> > @@ -15,7 +15,17 @@ >> > >> > #include "dw_mmc.h" >> > #include "dw_mmc-pltfm.h" >> > >> > -#define RK3288_CLKGEN_DIV 2 >> > +#define RK3288_CLKGEN_DIV 2 >> > +#define SDMMC_TIMING_CON0 0x130 >> > +#define SDMMC_TIMING_CON1 0x134 >> > +#define ROCKCHIP_MMC_DELAY_SEL BIT(10) >> > +#define ROCKCHIP_MMC_DEGREE_MASK 0x3 >> > +#define ROCKCHIP_MMC_DEGREE_OFFSET 1 >> > +#define ROCKCHIP_MMC_DELAYNUM_OFFSET 2 >> > +#define ROCKCHIP_MMC_DELAYNUM_MASK (0xff << >> > ROCKCHIP_MMC_DELAYNUM_OFFSET) >> > +#define ROCKCHIP_MMC_DELAY_ELEMENT_PSEC 60 >> > +#define HIWORD_UPDATE(val, mask, shift) \ >> > + ((val) << (shift) | (mask) << ((shift) + 16)) >> > >> > static const unsigned int freqs[] = { 100000, 200000, 300000, 400000 >> > >> > }; >> > >> > @@ -24,8 +34,143 @@ struct dw_mci_rockchip_priv_data { >> > >> > struct clk *sample_clk; >> > int default_sample_phase; >> > int num_phases; >> > >> > + int internal_phase; >> > >> > }; >> >> It might be good to declare internal_phase as "unsigned int >> internal_phase:1", >> i.e. as a bit field, which isn't going to save some memory in this >> particular >> case, but it would show additional attention to detail. > > In that case, I would go with a bool instead of int, that makes things > even clearer. My suggestion to use "unsigned int internal_phase:1" actually takes inspiration from the ASoC code, in which such bit fields are used quite a lot, even when using them actually doesn't save space. In this particular case, using plain bool would make sense, but I still think that using an "unsigned int internal_phase:1" bit field would fit better, because it would show the intention to possibly save a bit of RAM at some point. OTOH, I don't think that using bool with such bit fields would actually work cleanly, because bool actually resolves to int that's a signed type.
On Monday, 26 August 2024 10:39:58 EDT Dragan Simic wrote: > Hello Detlev, > > On 2024-08-23 15:34, Detlev Casanova wrote: > > On Friday, 23 August 2024 01:41:44 EDT Dragan Simic wrote: > >> Hello Detlev, > >> > >> Please see a comment below. > >> > >> On 2024-08-22 23:15, Detlev Casanova wrote: > >> > From: Shawn Lin <shawn.lin@rock-chips.com> > >> > > >> > Some Rockchip devices put the phase settings into the dw_mmc > >> > controller. > >> > > >> > When the feature is present, the ciu-drive and ciu-sample clocks are > >> > not used and the phase configuration is done directly through the mmc > >> > controller. > >> > > >> > Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com> > >> > Signed-off-by: Detlev Casanova <detlev.casanova@collabora.com> > >> > Acked-by: Shawn Lin <shawn.lin@rock-chips.com> > >> > --- > >> > > >> > drivers/mmc/host/dw_mmc-rockchip.c | 171 +++++++++++++++++++++++++++-- > >> > 1 file changed, 160 insertions(+), 11 deletions(-) > >> > > >> > diff --git a/drivers/mmc/host/dw_mmc-rockchip.c > >> > b/drivers/mmc/host/dw_mmc-rockchip.c > >> > index b07190ba4b7a..2748f9bf2691 100644 > >> > --- a/drivers/mmc/host/dw_mmc-rockchip.c > >> > +++ b/drivers/mmc/host/dw_mmc-rockchip.c > >> > @@ -15,7 +15,17 @@ > >> > > >> > #include "dw_mmc.h" > >> > #include "dw_mmc-pltfm.h" > >> > > >> > -#define RK3288_CLKGEN_DIV 2 > >> > +#define RK3288_CLKGEN_DIV 2 > >> > +#define SDMMC_TIMING_CON0 0x130 > >> > +#define SDMMC_TIMING_CON1 0x134 > >> > +#define ROCKCHIP_MMC_DELAY_SEL BIT(10) > >> > +#define ROCKCHIP_MMC_DEGREE_MASK 0x3 > >> > +#define ROCKCHIP_MMC_DEGREE_OFFSET 1 > >> > +#define ROCKCHIP_MMC_DELAYNUM_OFFSET 2 > >> > +#define ROCKCHIP_MMC_DELAYNUM_MASK (0xff << > >> > ROCKCHIP_MMC_DELAYNUM_OFFSET) > >> > +#define ROCKCHIP_MMC_DELAY_ELEMENT_PSEC 60 > >> > +#define HIWORD_UPDATE(val, mask, shift) \ > >> > + ((val) << (shift) | (mask) << ((shift) + 16)) > >> > > >> > static const unsigned int freqs[] = { 100000, 200000, 300000, 400000 > >> > > >> > }; > >> > > >> > @@ -24,8 +34,143 @@ struct dw_mci_rockchip_priv_data { > >> > > >> > struct clk *sample_clk; > >> > int default_sample_phase; > >> > int num_phases; > >> > > >> > + int internal_phase; > >> > > >> > }; > >> > >> It might be good to declare internal_phase as "unsigned int > >> internal_phase:1", > >> i.e. as a bit field, which isn't going to save some memory in this > >> particular > >> case, but it would show additional attention to detail. > > > > In that case, I would go with a bool instead of int, that makes things > > even clearer. > > My suggestion to use "unsigned int internal_phase:1" actually takes > inspiration from the ASoC code, in which such bit fields are used > quite a lot, even when using them actually doesn't save space. > > In this particular case, using plain bool would make sense, but I > still think that using an "unsigned int internal_phase:1" bit field > would fit better, because it would show the intention to possibly > save a bit of RAM at some point. OTOH, I don't think that using > bool with such bit fields would actually work cleanly, because bool > actually resolves to int that's a signed type. I wouldn't use bool with a bit field of course. I've always considered using bit fileds only for structs that must have a certain format, like a header format definition. For me, it is better to use "bool internal_phase" so that it is obvious that the feature can be on or off when reading the code. When using bit fields with a struct that is not marked as "__packed", I immediately think that there could be a bug there and wonder why the bit field is used, not really thinking "the dev wanted to show they cared about memory usage". But I guess that is all about preferences. In the end, it won't change how it works. Detlev.
diff --git a/drivers/mmc/host/dw_mmc-rockchip.c b/drivers/mmc/host/dw_mmc-rockchip.c index b07190ba4b7a..2748f9bf2691 100644 --- a/drivers/mmc/host/dw_mmc-rockchip.c +++ b/drivers/mmc/host/dw_mmc-rockchip.c @@ -15,7 +15,17 @@ #include "dw_mmc.h" #include "dw_mmc-pltfm.h" -#define RK3288_CLKGEN_DIV 2 +#define RK3288_CLKGEN_DIV 2 +#define SDMMC_TIMING_CON0 0x130 +#define SDMMC_TIMING_CON1 0x134 +#define ROCKCHIP_MMC_DELAY_SEL BIT(10) +#define ROCKCHIP_MMC_DEGREE_MASK 0x3 +#define ROCKCHIP_MMC_DEGREE_OFFSET 1 +#define ROCKCHIP_MMC_DELAYNUM_OFFSET 2 +#define ROCKCHIP_MMC_DELAYNUM_MASK (0xff << ROCKCHIP_MMC_DELAYNUM_OFFSET) +#define ROCKCHIP_MMC_DELAY_ELEMENT_PSEC 60 +#define HIWORD_UPDATE(val, mask, shift) \ + ((val) << (shift) | (mask) << ((shift) + 16)) static const unsigned int freqs[] = { 100000, 200000, 300000, 400000 }; @@ -24,8 +34,143 @@ struct dw_mci_rockchip_priv_data { struct clk *sample_clk; int default_sample_phase; int num_phases; + int internal_phase; }; +/* + * Each fine delay is between 44ps-77ps. Assume each fine delay is 60ps to + * simplify calculations. So 45degs could be anywhere between 33deg and 57.8deg. + */ +static int rockchip_mmc_get_internal_phase(struct dw_mci *host, bool sample) +{ + unsigned long rate = clk_get_rate(host->ciu_clk); + u32 raw_value; + u16 degrees; + u32 delay_num = 0; + + /* Constant signal, no measurable phase shift */ + if (!rate) + return 0; + + if (sample) + raw_value = mci_readl(host, TIMING_CON1); + else + raw_value = mci_readl(host, TIMING_CON0); + + raw_value >>= ROCKCHIP_MMC_DEGREE_OFFSET; + degrees = (raw_value & ROCKCHIP_MMC_DEGREE_MASK) * 90; + + if (raw_value & ROCKCHIP_MMC_DELAY_SEL) { + /* degrees/delaynum * 1000000 */ + unsigned long factor = (ROCKCHIP_MMC_DELAY_ELEMENT_PSEC / 10) * + 36 * (rate / 10000); + + delay_num = (raw_value & ROCKCHIP_MMC_DELAYNUM_MASK); + delay_num >>= ROCKCHIP_MMC_DELAYNUM_OFFSET; + degrees += DIV_ROUND_CLOSEST(delay_num * factor, 1000000); + } + + return degrees % 360; +} + +static int rockchip_mmc_get_phase(struct dw_mci *host, bool sample) +{ + struct dw_mci_rockchip_priv_data *priv = host->priv; + struct clk *clock = sample ? priv->sample_clk : priv->drv_clk; + + if (priv->internal_phase) + return rockchip_mmc_get_internal_phase(host, sample); + else + return clk_get_phase(clock); +} + +static int rockchip_mmc_set_internal_phase(struct dw_mci *host, bool sample, int degrees) +{ + unsigned long rate = clk_get_rate(host->ciu_clk); + u8 nineties, remainder; + u8 delay_num; + u32 raw_value; + u32 delay; + + /* + * The below calculation is based on the output clock from + * MMC host to the card, which expects the phase clock inherits + * the clock rate from its parent, namely the output clock + * provider of MMC host. However, things may go wrong if + * (1) It is orphan. + * (2) It is assigned to the wrong parent. + * + * This check help debug the case (1), which seems to be the + * most likely problem we often face and which makes it difficult + * for people to debug unstable mmc tuning results. + */ + if (!rate) { + dev_err(host->dev, "%s: invalid clk rate\n", __func__); + return -EINVAL; + } + + nineties = degrees / 90; + remainder = (degrees % 90); + + /* + * Due to the inexact nature of the "fine" delay, we might + * actually go non-monotonic. We don't go _too_ monotonic + * though, so we should be OK. Here are options of how we may + * work: + * + * Ideally we end up with: + * 1.0, 2.0, ..., 69.0, 70.0, ..., 89.0, 90.0 + * + * On one extreme (if delay is actually 44ps): + * .73, 1.5, ..., 50.6, 51.3, ..., 65.3, 90.0 + * The other (if delay is actually 77ps): + * 1.3, 2.6, ..., 88.6. 89.8, ..., 114.0, 90 + * + * It's possible we might make a delay that is up to 25 + * degrees off from what we think we're making. That's OK + * though because we should be REALLY far from any bad range. + */ + + /* + * Convert to delay; do a little extra work to make sure we + * don't overflow 32-bit / 64-bit numbers. + */ + delay = 10000000; /* PSECS_PER_SEC / 10000 / 10 */ + delay *= remainder; + delay = DIV_ROUND_CLOSEST(delay, + (rate / 1000) * 36 * + (ROCKCHIP_MMC_DELAY_ELEMENT_PSEC / 10)); + + delay_num = (u8) min_t(u32, delay, 255); + + raw_value = delay_num ? ROCKCHIP_MMC_DELAY_SEL : 0; + raw_value |= delay_num << ROCKCHIP_MMC_DELAYNUM_OFFSET; + raw_value |= nineties; + + if (sample) + mci_writel(host, TIMING_CON1, HIWORD_UPDATE(raw_value, 0x07ff, 1)); + else + mci_writel(host, TIMING_CON0, HIWORD_UPDATE(raw_value, 0x07ff, 1)); + + dev_dbg(host->dev, "set %s_phase(%d) delay_nums=%u actual_degrees=%d\n", + sample ? "sample" : "drv", degrees, delay_num, + rockchip_mmc_get_phase(host, sample) + ); + + return 0; +} + +static int rockchip_mmc_set_phase(struct dw_mci *host, bool sample, int degrees) +{ + struct dw_mci_rockchip_priv_data *priv = host->priv; + struct clk *clock = sample ? priv->sample_clk : priv->drv_clk; + + if (priv->internal_phase) + return rockchip_mmc_set_internal_phase(host, sample, degrees); + else + return clk_set_phase(clock, degrees); +} + static void dw_mci_rk3288_set_ios(struct dw_mci *host, struct mmc_ios *ios) { struct dw_mci_rockchip_priv_data *priv = host->priv; @@ -64,7 +209,7 @@ static void dw_mci_rk3288_set_ios(struct dw_mci *host, struct mmc_ios *ios) /* Make sure we use phases which we can enumerate with */ if (!IS_ERR(priv->sample_clk) && ios->timing <= MMC_TIMING_SD_HS) - clk_set_phase(priv->sample_clk, priv->default_sample_phase); + rockchip_mmc_set_phase(host, true, priv->default_sample_phase); /* * Set the drive phase offset based on speed mode to achieve hold times. @@ -127,7 +272,7 @@ static void dw_mci_rk3288_set_ios(struct dw_mci *host, struct mmc_ios *ios) break; } - clk_set_phase(priv->drv_clk, phase); + rockchip_mmc_set_phase(host, false, phase); } } @@ -151,6 +296,7 @@ static int dw_mci_rk3288_execute_tuning(struct dw_mci_slot *slot, u32 opcode) int longest_range_len = -1; int longest_range = -1; int middle_phase; + int phase; if (IS_ERR(priv->sample_clk)) { dev_err(host->dev, "Tuning clock (sample_clk) not defined.\n"); @@ -164,8 +310,10 @@ static int dw_mci_rk3288_execute_tuning(struct dw_mci_slot *slot, u32 opcode) /* Try each phase and extract good ranges */ for (i = 0; i < priv->num_phases; ) { - clk_set_phase(priv->sample_clk, - TUNING_ITERATION_TO_PHASE(i, priv->num_phases)); + rockchip_mmc_set_phase(host, true, + TUNING_ITERATION_TO_PHASE( + i, + priv->num_phases)); v = !mmc_send_tuning(mmc, opcode, NULL); @@ -211,7 +359,8 @@ static int dw_mci_rk3288_execute_tuning(struct dw_mci_slot *slot, u32 opcode) } if (ranges[0].start == 0 && ranges[0].end == priv->num_phases - 1) { - clk_set_phase(priv->sample_clk, priv->default_sample_phase); + rockchip_mmc_set_phase(host, true, priv->default_sample_phase); + dev_info(host->dev, "All phases work, using default phase %d.", priv->default_sample_phase); goto free; @@ -248,12 +397,10 @@ static int dw_mci_rk3288_execute_tuning(struct dw_mci_slot *slot, u32 opcode) middle_phase = ranges[longest_range].start + longest_range_len / 2; middle_phase %= priv->num_phases; - dev_info(host->dev, "Successfully tuned phase to %d\n", - TUNING_ITERATION_TO_PHASE(middle_phase, priv->num_phases)); + phase = TUNING_ITERATION_TO_PHASE(middle_phase, priv->num_phases); + dev_info(host->dev, "Successfully tuned phase to %d\n", phase); - clk_set_phase(priv->sample_clk, - TUNING_ITERATION_TO_PHASE(middle_phase, - priv->num_phases)); + rockchip_mmc_set_phase(host, true, phase); free: kfree(ranges); @@ -287,6 +434,8 @@ static int dw_mci_rk3288_parse_dt(struct dw_mci *host) host->priv = priv; + priv->internal_phase = false; + return 0; }