Re: [U-Boot] [PATCH v2] mmc: sdhci: Add the programmable clock mode support

Hi Kever,

On 09/30/2016 07:05 PM, Kever Yang wrote:

Hi Wenyou,

I can not enable my emmc device  on my evb-rk3399 with this patch, could you help to fix it?

Here is the debug info may help:

mmc->cfg->f_max is 200000000;

[with this patch] I get host->clk_mul 16 ; When driver want to set clock to 400000, always get div 1024, and then write 0x21 to SDHCI_CLOCK_CONTROL register, mmc controller can not work because of the wrong clock rate;

[without this patch] we don't use host->clk_mul; When driver want to set clock to 400000, get div 250, and then write 0xfa01 to SDHCI_CLOCK_CONTROL register, mmc controller works OK.

If you don't use host->clk_mul, then your host controller is the lower version than V3.0..?

host->clk_mul is assigned to dummy value? Could you check this?

When i have checked Whenyou's patch, there is only difference about "host->clk_mul".

Best Regards, Jaehoon Chung

Thanks,

• Kever

On 09/18/2016 09:01 AM, Wenyou Yang wrote:

...

Add the programmable clock mode for the clock generator.

Signed-off-by: Wenyou Yang wenyou.yang@atmel.com

Changes in v2:

• Rebase on the latest u-boot-mmc.
• Fix the typo Muliplier->Multiplier.

drivers/mmc/sdhci.c | 50 ++++++++++++++++++++++++++++++++++++++++---------- include/sdhci.h | 2 ++ 2 files changed, 42 insertions(+), 10 deletions(-)

diff --git a/drivers/mmc/sdhci.c b/drivers/mmc/sdhci.c index 504f2d2..b2bf5a0 100644 --- a/drivers/mmc/sdhci.c +++ b/drivers/mmc/sdhci.c @@ -294,7 +294,7 @@ static int sdhci_send_command(struct mmc *mmc, struct mmc_cmd *cmd, static int sdhci_set_clock(struct mmc *mmc, unsigned int clock) { struct sdhci_host *host = mmc->priv;

• unsigned int div, clk, timeout, reg;

• unsigned int div, clk = 0, timeout, reg; /* Wait max 20 ms */ timeout = 200;

@@ -318,14 +318,36 @@ static int sdhci_set_clock(struct mmc *mmc, unsigned int clock) return 0; if (SDHCI_GET_VERSION(host) >= SDHCI_SPEC_300) {

•    /* Version 3.00 divisors must be a multiple of 2. */
  

•    if (mmc->cfg->f_max <= clock)
  

•        div = 1;
  

•    else {
  

•        for (div = 2; div < SDHCI_MAX_DIV_SPEC_300; div += 2) {
  

•            if ((mmc->cfg->f_max / div) <= clock)
  

•    /*
  

•     * Check if the Host Controller supports Programmable Clock
  

•     * Mode.
  

•     */
  

•    if (host->clk_mul) {
  

•        for (div = 1; div <= 1024; div++) {
  

•            if ((mmc->cfg->f_max * host->clk_mul / div)
  

•                <= clock)
                  break;
          }
  

•        /*
  

•         * Set Programmable Clock Mode in the Clock
  

•         * Control register.
  

•         */
  

•        clk = SDHCI_PROG_CLOCK_MODE;
  

•        div--;
  

•    } else {
  

•        /* Version 3.00 divisors must be a multiple of 2. */
  

•        if (mmc->cfg->f_max <= clock) {
  

•            div = 1;
  

•        } else {
  

•            for (div = 2;
  

•                 div < SDHCI_MAX_DIV_SPEC_300;
  

•                 div += 2) {
  

•                if ((mmc->cfg->f_max / div) <= clock)
  

•                    break;
  

•            }
  

•        }
  

•        div >>= 1;
      }
  } else {
      /* Version 2.00 divisors must be a power of 2. */
  

@@ -333,13 +355,13 @@ static int sdhci_set_clock(struct mmc *mmc, unsigned int clock) if ((mmc->cfg->f_max / div) <= clock) break; }

•    div >>= 1;
  }
  

• div >>= 1; if (host->set_clock) host->set_clock(host->index, div);
  • clk = (div & SDHCI_DIV_MASK) << SDHCI_DIVIDER_SHIFT;

• clk |= (div & SDHCI_DIV_MASK) << SDHCI_DIVIDER_SHIFT; clk |= ((div & SDHCI_DIV_HI_MASK) >> SDHCI_DIV_MASK_LEN) << SDHCI_DIVIDER_HI_SHIFT; clk |= SDHCI_CLOCK_INT_EN;

@@ -513,7 +535,7 @@ static const struct mmc_ops sdhci_ops = { int sdhci_setup_cfg(struct mmc_config *cfg, struct sdhci_host *host, u32 max_clk, u32 min_clk) {

• u32 caps;

• u32 caps, caps_1; caps = sdhci_readl(host, SDHCI_CAPABILITIES); @@ -577,6 +599,14 @@ int sdhci_setup_cfg(struct mmc_config *cfg, struct sdhci_host *host, cfg->b_max = CONFIG_SYS_MMC_MAX_BLK_COUNT;
  • /*

• * In case of Host Controller v3.00, find out whether clock
  

• * multiplier is supported.
  

• */
  

• caps_1 = sdhci_readl(host, SDHCI_CAPABILITIES_1);
• host->clk_mul = (caps_1 & SDHCI_CLOCK_MUL_MASK) >>

•        SDHCI_CLOCK_MUL_SHIFT;
  

• return 0;
  

  } diff --git a/include/sdhci.h b/include/sdhci.h

index 6844c73..144570f 100644 --- a/include/sdhci.h +++ b/include/sdhci.h @@ -97,6 +97,7 @@ #define SDHCI_DIV_MASK 0xFF #define SDHCI_DIV_MASK_LEN 8 #define SDHCI_DIV_HI_MASK 0x300 +#define SDHCI_PROG_CLOCK_MODE 0x0020 #define SDHCI_CLOCK_CARD_EN 0x0004 #define SDHCI_CLOCK_INT_STABLE 0x0002 #define SDHCI_CLOCK_INT_EN 0x0001 @@ -242,6 +243,7 @@ struct sdhci_host { unsigned int quirks; unsigned int host_caps; unsigned int version;

• unsigned int clk_mul; /* Clock Multiplier value */ unsigned int clock; struct mmc *mmc; const struct sdhci_ops *ops;