[PATCH v3 1/4] mmc: dw_mmc: exynos: incorporate ciu_div into timing property
Jaehoon Chung
jh80.chung at samsung.com
Wed Jan 7 17:36:32 PST 2015
Hi,
On 12/31/2014 03:43 PM, Alim Akhtar wrote:
> From: Seungwon Jeon <tgih.jun at samsung.com>
>
> ciu_div may not be common value for all speed mode.
> So, it needs to be attached to CLKSEL timing.
> This also introduce a new compatibale 'dw-mshc-hs200-timing'
> for selecting hs200 timing value
>
> Signed-off-by: Seungwon Jeon <tgih.jun at samsung.com>
> Signed-off-by: Alim Akhtar <alim.akhtar at samsung.com>
> ---
> .../devicetree/bindings/mmc/exynos-dw-mshc.txt | 15 ++--
> drivers/mmc/host/dw_mmc-exynos.c | 81 ++++++++++++++------
> drivers/mmc/host/dw_mmc-exynos.h | 1 +
> 3 files changed, 67 insertions(+), 30 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt b/Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt
> index ee4fc05..06455de 100644
> --- a/Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt
> +++ b/Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt
> @@ -23,10 +23,6 @@ Required Properties:
> - "samsung,exynos7-dw-mshc-smu": for controllers with Samsung Exynos7
> specific extensions having an SMU.
>
> -* samsung,dw-mshc-ciu-div: Specifies the divider value for the card interface
> - unit (ciu) clock. This property is applicable only for Exynos5 SoC's and
> - ignored for Exynos4 SoC's. The valid range of divider value is 0 to 7.
> -
> * samsung,dw-mshc-sdr-timing: Specifies the value of CIU clock phase shift value
> in transmit mode and CIU clock phase shift value in receive mode for single
> data rate mode operation. Refer notes below for the order of the cells and the
> @@ -37,11 +33,16 @@ Required Properties:
> data rate mode operation. Refer notes below for the order of the cells and the
> valid values.
>
> +* samsung,dw-mshc-hs200-timing: Similar with dw-mshc-sdr-timing.
What does this comment mean? "Similar with dw-mshc-sdr-timing"
how about adding the comment "optional"?
And i think this timing doesn't need, we can reuse the sdr-timing or ddr-timing.
Because it's re-configurated at tuning time, isn't?
> +
> Notes for the sdr-timing and ddr-timing values:
>
> The order of the cells should be
> - First Cell: CIU clock phase shift value for tx mode.
> - Second Cell: CIU clock phase shift value for rx mode.
> + - Thrid Cell: Specifies the divider value for the card interface
> + unit (ciu) clock. This property is applicable only for Exynos5 SoC's and
> + ignored for Exynos4 SoC's. The valid range of divider value is 0 to 7.
>
> Valid values for SDR and DDR CIU clock timing for Exynos5250:
> - valid value for tx phase shift and rx phase shift is 0 to 7.
> @@ -79,8 +80,8 @@ Example:
> broken-cd;
> fifo-depth = <0x80>;
> card-detect-delay = <200>;
> - samsung,dw-mshc-ciu-div = <3>;
> - samsung,dw-mshc-sdr-timing = <2 3>;
> - samsung,dw-mshc-ddr-timing = <1 2>;
> + samsung,dw-mshc-sdr-timing = <2 3 3>;
> + samsung,dw-mshc-ddr-timing = <1 2 3>;
> + samsung,dw-mshc-hs200-timing = <0 2 3>;
> bus-width = <8>;
> };
> diff --git a/drivers/mmc/host/dw_mmc-exynos.c b/drivers/mmc/host/dw_mmc-exynos.c
> index 12a5eaa..be6530e 100644
> --- a/drivers/mmc/host/dw_mmc-exynos.c
> +++ b/drivers/mmc/host/dw_mmc-exynos.c
> @@ -40,6 +40,7 @@ struct dw_mci_exynos_priv_data {
> u8 ciu_div;
> u32 sdr_timing;
> u32 ddr_timing;
> + u32 hs200_timing;
> u32 cur_speed;
> };
>
> @@ -71,6 +72,21 @@ static struct dw_mci_exynos_compatible {
> },
> };
>
> +static inline u8 dw_mci_exynos_get_ciu_div(struct dw_mci *host)
> +{
> + struct dw_mci_exynos_priv_data *priv = host->priv;
> +
> + if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS4412)
> + return EXYNOS4412_FIXED_CIU_CLK_DIV;
> + else if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS4210)
> + return EXYNOS4210_FIXED_CIU_CLK_DIV;
> + else if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
> + priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU)
> + return SDMMC_CLKSEL_GET_DIV(mci_readl(host, CLKSEL64)) + 1;
> + else
> + return SDMMC_CLKSEL_GET_DIV(mci_readl(host, CLKSEL)) + 1;
If need this, I think more readable that use the switch-case statement. how about?
switch (priv->ctrl_type) {
case DW_MCI_TYPE_EXYNOS4412:
return EXYNOS4412_FIXED_CIU_CLK_DIV;
case DW_MCI_TYPE_EXYNOS4210:
return EXYNOS4210_FIXED_CIU_CLK_DIV;
case DW_MCI_TYPE_EXYNOS7:
case DW_MCI_TYPE_EXYNOS7_SMU:
return SDMMC_CLKSEL_GET_DIV(mci_readl(host, CLKSEL64)) + 1;
default:
return SDMMC_CLKSEL_GET_DIV(mci_readl(host, CLKSEL)) + 1;
}
> +}
> +
> static int dw_mci_exynos_priv_init(struct dw_mci *host)
> {
> struct dw_mci_exynos_priv_data *priv = host->priv;
> @@ -85,6 +101,8 @@ static int dw_mci_exynos_priv_init(struct dw_mci *host)
> SDMMC_MPSCTRL_NON_SECURE_WRITE_BIT);
> }
>
> + priv->ciu_div = dw_mci_exynos_get_ciu_div(host);
> +
> return 0;
> }
>
> @@ -92,7 +110,7 @@ static int dw_mci_exynos_setup_clock(struct dw_mci *host)
> {
> struct dw_mci_exynos_priv_data *priv = host->priv;
>
> - host->bus_hz /= (priv->ciu_div + 1);
> + host->bus_hz /= priv->ciu_div;
>
> return 0;
> }
> @@ -177,9 +195,14 @@ static void dw_mci_exynos_set_ios(struct dw_mci *host, struct mmc_ios *ios)
> struct dw_mci_exynos_priv_data *priv = host->priv;
> unsigned int wanted = ios->clock;
> unsigned long actual;
> - u8 div = priv->ciu_div + 1;
>
> - if (ios->timing == MMC_TIMING_MMC_DDR52) {
> + if (ios->timing == MMC_TIMING_MMC_HS200) {
> + if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
> + priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU)
> + mci_writel(host, CLKSEL64, priv->hs200_timing);
> + else
> + mci_writel(host, CLKSEL, priv->hs200_timing);
> + } else if (ios->timing == MMC_TIMING_MMC_DDR52) {
> if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
> priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU)
> mci_writel(host, CLKSEL64, priv->ddr_timing);
> @@ -208,6 +231,7 @@ static void dw_mci_exynos_set_ios(struct dw_mci *host, struct mmc_ios *ios)
> wanted = EXYNOS_CCLKIN_MIN;
>
> if (wanted != priv->cur_speed) {
> + u8 div = dw_mci_exynos_get_ciu_div(host);
> int ret = clk_set_rate(host->ciu_clk, wanted * div);
> if (ret)
> dev_warn(host->dev,
> @@ -220,14 +244,34 @@ static void dw_mci_exynos_set_ios(struct dw_mci *host, struct mmc_ios *ios)
> }
> }
>
> +static int dw_mci_exynos_dt_populate_timing(struct dw_mci *host,
> + unsigned int ctrl_type,
> + const char *propname,
> + u32 *out_values)
> +{
> + struct device_node *np = host->dev->of_node;
> + u32 timing[3];
> + int ret;
> +
> + ret = of_property_read_u32_array(np, propname, timing, 3);
> + if (ret)
> + return ret;
> +
> + if (ctrl_type == DW_MCI_TYPE_EXYNOS4412 ||
> + ctrl_type == DW_MCI_TYPE_EXYNOS4210)
> + timing[2] = 0;
Is it set to 0 into dt-file?
> +
> + *out_values = SDMMC_CLKSEL_TIMING(timing[0], timing[1], timing[2]);
> +
> + return 0;
> +}
> +
> +
> static int dw_mci_exynos_parse_dt(struct dw_mci *host)
> {
> struct dw_mci_exynos_priv_data *priv;
> struct device_node *np = host->dev->of_node;
> - u32 timing[2];
> - u32 div = 0;
> - int idx;
> - int ret;
> + int idx, ret;
>
> priv = devm_kzalloc(host->dev, sizeof(*priv), GFP_KERNEL);
> if (!priv)
> @@ -238,29 +282,20 @@ static int dw_mci_exynos_parse_dt(struct dw_mci *host)
> priv->ctrl_type = exynos_compat[idx].ctrl_type;
> }
>
> - if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS4412)
> - priv->ciu_div = EXYNOS4412_FIXED_CIU_CLK_DIV - 1;
> - else if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS4210)
> - priv->ciu_div = EXYNOS4210_FIXED_CIU_CLK_DIV - 1;
> - else {
> - of_property_read_u32(np, "samsung,dw-mshc-ciu-div", &div);
> - priv->ciu_div = div;
> - }
> -
> - ret = of_property_read_u32_array(np,
> - "samsung,dw-mshc-sdr-timing", timing, 2);
> + ret = dw_mci_exynos_dt_populate_timing(host, priv->ctrl_type,
> + "samsung,dw-mshc-sdr-timing", &priv->sdr_timing);
> if (ret)
> return ret;
>
> - priv->sdr_timing = SDMMC_CLKSEL_TIMING(timing[0], timing[1], div);
> -
> - ret = of_property_read_u32_array(np,
> - "samsung,dw-mshc-ddr-timing", timing, 2);
> + ret = dw_mci_exynos_dt_populate_timing(host, priv->ctrl_type,
> + "samsung,dw-mshc-ddr-timing", &priv->ddr_timing);
> if (ret)
> return ret;
>
> - priv->ddr_timing = SDMMC_CLKSEL_TIMING(timing[0], timing[1], div);
> + dw_mci_exynos_dt_populate_timing(host, priv->ctrl_type,
> + "samsung,dw-mshc-hs200-timing", &priv->hs200_timing);
hs200-timing is optional, so it needs not to check return value, right?
Best Regards,
Jaehoon Chung
> host->priv = priv;
> +
> return 0;
> }
>
> diff --git a/drivers/mmc/host/dw_mmc-exynos.h b/drivers/mmc/host/dw_mmc-exynos.h
> index 7872ce5..c04ecef 100644
> --- a/drivers/mmc/host/dw_mmc-exynos.h
> +++ b/drivers/mmc/host/dw_mmc-exynos.h
> @@ -21,6 +21,7 @@
> #define SDMMC_CLKSEL_CCLK_DRIVE(x) (((x) & 7) << 16)
> #define SDMMC_CLKSEL_CCLK_DIVIDER(x) (((x) & 7) << 24)
> #define SDMMC_CLKSEL_GET_DRV_WD3(x) (((x) >> 16) & 0x7)
> +#define SDMMC_CLKSEL_GET_DIV(x) (((x) >> 24) & 0x7)
> #define SDMMC_CLKSEL_TIMING(x, y, z) (SDMMC_CLKSEL_CCLK_SAMPLE(x) | \
> SDMMC_CLKSEL_CCLK_DRIVE(y) | \
> SDMMC_CLKSEL_CCLK_DIVIDER(z))
>
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