[PATCH v3 2/4] mmc: dw_mmc: exynos: support eMMC's HS400 mode
Jaehoon Chung
jh80.chung at samsung.com
Wed Jan 7 17:46:32 PST 2015
On 12/31/2014 03:43 PM, Alim Akhtar wrote:
> From: Seungwon Jeon <tgih.jun at samsung.com>
>
> Implements HS400 support for exynos host driver.
> And this patch includes some updates as new mode is added.
>
> 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 | 6 +
> drivers/mmc/host/dw_mmc-exynos.c | 177 +++++++++++++++-----
> drivers/mmc/host/dw_mmc-exynos.h | 17 +-
> drivers/mmc/host/dw_mmc.c | 16 +-
> drivers/mmc/host/dw_mmc.h | 2 +
> 5 files changed, 178 insertions(+), 40 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt b/Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt
> index 06455de..be30c94 100644
> --- a/Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt
> +++ b/Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt
> @@ -34,6 +34,7 @@ Required Properties:
> valid values.
>
> * samsung,dw-mshc-hs200-timing: Similar with dw-mshc-sdr-timing.
> +* samsung,dw-mshc-hs400-timing: Similar with dw-mshc-ddr-timing.
>
> Notes for the sdr-timing and ddr-timing values:
>
> @@ -51,6 +52,9 @@ Required Properties:
> - if CIU clock divider value is 0 (that is divide by 1), both tx and rx
> phase shift clocks should be 0.
>
> +* read-strobe-delay: RCLK (Data strobe) delay to control HS400 mode
> + (Latency value for delay line in Read path)
> +
> Required properties for a slot (Deprecated - Recommend to use one slot per host):
>
> * gpios: specifies a list of gpios used for command, clock and data bus. The
> @@ -83,5 +87,7 @@ Example:
> samsung,dw-mshc-sdr-timing = <2 3 3>;
> samsung,dw-mshc-ddr-timing = <1 2 3>;
> samsung,dw-mshc-hs200-timing = <0 2 3>;
> + samsung,dw-mshc-hs400-timing = <0 2 1>;
> + read-strobe-delay = <90>;
> bus-width = <8>;
> };
> diff --git a/drivers/mmc/host/dw_mmc-exynos.c b/drivers/mmc/host/dw_mmc-exynos.c
> index be6530e..d37a631 100644
> --- a/drivers/mmc/host/dw_mmc-exynos.c
> +++ b/drivers/mmc/host/dw_mmc-exynos.c
> @@ -41,7 +41,12 @@ struct dw_mci_exynos_priv_data {
> u32 sdr_timing;
> u32 ddr_timing;
> u32 hs200_timing;
> + u32 hs400_timing;
> + u32 tuned_sample;
> u32 cur_speed;
> + u32 dqs_delay;
> + u32 saved_dqs_en;
> + u32 saved_strobe_ctrl;
> };
>
> static struct dw_mci_exynos_compatible {
> @@ -101,6 +106,16 @@ static int dw_mci_exynos_priv_init(struct dw_mci *host)
> SDMMC_MPSCTRL_NON_SECURE_WRITE_BIT);
> }
>
> + if (priv->ctrl_type >= DW_MCI_TYPE_EXYNOS5420) {
> + priv->saved_strobe_ctrl = mci_readl(host, HS400_DLINE_CTRL);
> + priv->saved_dqs_en = mci_readl(host, HS400_DQS_EN);
> + priv->saved_dqs_en |= AXI_NON_BLOCKING_WR;
> + mci_writel(host, HS400_DQS_EN, priv->saved_dqs_en);
> + if (!priv->dqs_delay)
> + priv->dqs_delay =
> + DQS_CTRL_GET_RD_DELAY(priv->saved_strobe_ctrl);
> + }
> +
> priv->ciu_div = dw_mci_exynos_get_ciu_div(host);
>
> return 0;
> @@ -115,6 +130,25 @@ static int dw_mci_exynos_setup_clock(struct dw_mci *host)
> return 0;
> }
>
> +static void dw_mci_exynos_set_clksel_timing(struct dw_mci *host, u32 timing)
> +{
> + struct dw_mci_exynos_priv_data *priv = host->priv;
> + u32 clksel;
> +
> + if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
> + priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU)
> + clksel = mci_readl(host, CLKSEL64);
> + else
> + clksel = mci_readl(host, CLKSEL);
> +
> + clksel = (clksel & ~SDMMC_CLKSEL_TIMING_MASK) | timing;
> + if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
> + priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU)
> + mci_writel(host, CLKSEL64, clksel);
> + else
> + mci_writel(host, CLKSEL, clksel);
> +}
> +
> #ifdef CONFIG_PM_SLEEP
> static int dw_mci_exynos_suspend(struct device *dev)
> {
> @@ -190,35 +224,37 @@ static void dw_mci_exynos_prepare_command(struct dw_mci *host, u32 *cmdr)
> }
> }
>
> -static void dw_mci_exynos_set_ios(struct dw_mci *host, struct mmc_ios *ios)
> +static void dw_mci_exynos_config_hs400(struct dw_mci *host, u32 timing)
> {
> struct dw_mci_exynos_priv_data *priv = host->priv;
> - unsigned int wanted = ios->clock;
> - unsigned long actual;
> + u32 dqs, strobe;
>
> - 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);
> - else
> - mci_writel(host, CLKSEL, priv->ddr_timing);
> - /* Should be double rate for DDR mode */
> - if (ios->bus_width == MMC_BUS_WIDTH_8)
> - wanted <<= 1;
> + /*
> + * Exynos5420 and above controller supports HS400 mode
> + */
> + if (priv->ctrl_type < DW_MCI_TYPE_EXYNOS5420)
> + return;
> +
> + dqs = priv->saved_dqs_en;
> + strobe = priv->saved_strobe_ctrl;
> +
> + if (timing == MMC_TIMING_MMC_HS400) {
> + dqs |= DATA_STROBE_EN;
> + strobe = DQS_CTRL_RD_DELAY(strobe, priv->dqs_delay);
> } else {
> - if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
> - priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU)
> - mci_writel(host, CLKSEL64, priv->sdr_timing);
> - else
> - mci_writel(host, CLKSEL, priv->sdr_timing);
> + dqs &= ~DATA_STROBE_EN;
> }
>
> + mci_writel(host, HS400_DQS_EN, dqs);
> + mci_writel(host, HS400_DLINE_CTRL, strobe);
> +}
> +
> +static void dw_mci_exynos_adjust_clock(struct dw_mci *host, unsigned int wanted)
> +{
> + struct dw_mci_exynos_priv_data *priv = host->priv;
> + unsigned long actual;
> + u8 div;
> + int ret;
> /*
> * Don't care if wanted clock is zero or
> * ciu clock is unavailable
> @@ -230,18 +266,55 @@ static void dw_mci_exynos_set_ios(struct dw_mci *host, struct mmc_ios *ios)
> if (wanted < EXYNOS_CCLKIN_MIN)
> 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,
> - "failed to set clk-rate %u error: %d\n",
> - wanted * div, ret);
> - actual = clk_get_rate(host->ciu_clk);
> - host->bus_hz = actual / div;
> - priv->cur_speed = wanted;
> - host->current_speed = 0;
> + if (wanted == priv->cur_speed)
> + return;
> +
> + div = dw_mci_exynos_get_ciu_div(host);
> + ret = clk_set_rate(host->ciu_clk, wanted * div);
> + if (ret)
> + dev_warn(host->dev,
> + "failed to set clk-rate %u error: %d\n",
> + wanted * div, ret);
> + actual = clk_get_rate(host->ciu_clk);
> + host->bus_hz = actual / div;
> + priv->cur_speed = wanted;
> + host->current_speed = 0;
> +}
> +
> +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;
> + u32 timing = ios->timing, clksel;
> +
> + switch (timing) {
> + case MMC_TIMING_MMC_HS400:
> + /* Update tuned sample timing */
> + clksel = SDMMC_CLKSEL_UP_SAMPLE(
> + priv->hs400_timing, priv->tuned_sample);
> + wanted <<= 1;
> + break;
> + case MMC_TIMING_MMC_HS200:
> + clksel = priv->hs200_timing;
> + break;
> + case MMC_TIMING_MMC_DDR52:
> + clksel = priv->ddr_timing;
> + /* Should be double rate for DDR mode */
> + if (ios->bus_width == MMC_BUS_WIDTH_8)
> + wanted <<= 1;
> + break;
> + default:
> + clksel = priv->sdr_timing;
> }
> +
> + /* Set clock timing for the requested speed mode*/
> + dw_mci_exynos_set_clksel_timing(host, clksel);
> +
> + /* Configure setting for HS400 */
> + dw_mci_exynos_config_hs400(host, timing);
> +
> + /* Configure clock rate */
> + dw_mci_exynos_adjust_clock(host, wanted);
> }
>
> static int dw_mci_exynos_dt_populate_timing(struct dw_mci *host,
> @@ -294,6 +367,14 @@ static int dw_mci_exynos_parse_dt(struct dw_mci *host)
>
> dw_mci_exynos_dt_populate_timing(host, priv->ctrl_type,
> "samsung,dw-mshc-hs200-timing", &priv->hs200_timing);
> +
> + ret = dw_mci_exynos_dt_populate_timing(host, priv->ctrl_type,
> + "samsung,dw-mshc-hs400-timing", &priv->hs400_timing);
> + if (!ret && of_property_read_u32(np,
> + "read-strobe-delay", &priv->dqs_delay))
> + dev_info(host->dev,
> + "read-strobe-delay is not found, assuming usage of default value\n");
> +
> host->priv = priv;
>
> return 0;
> @@ -320,7 +401,9 @@ static inline void dw_mci_exynos_set_clksmpl(struct dw_mci *host, u8 sample)
> clksel = mci_readl(host, CLKSEL64);
> else
> clksel = mci_readl(host, CLKSEL);
> - clksel = (clksel & ~0x7) | SDMMC_CLKSEL_CCLK_SAMPLE(sample);
> +
> + clksel = SDMMC_CLKSEL_UP_SAMPLE(clksel, sample);
> +
> if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
> priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU)
> mci_writel(host, CLKSEL64, clksel);
> @@ -339,13 +422,16 @@ static inline u8 dw_mci_exynos_move_next_clksmpl(struct dw_mci *host)
> clksel = mci_readl(host, CLKSEL64);
> else
> clksel = mci_readl(host, CLKSEL);
> +
> sample = (clksel + 1) & 0x7;
> - clksel = (clksel & ~0x7) | sample;
> + clksel = SDMMC_CLKSEL_UP_SAMPLE(clksel, sample);
> +
> if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
> priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU)
> mci_writel(host, CLKSEL64, clksel);
> else
> mci_writel(host, CLKSEL, clksel);
> +
> return sample;
> }
>
> @@ -378,6 +464,7 @@ out:
> static int dw_mci_exynos_execute_tuning(struct dw_mci_slot *slot)
> {
> struct dw_mci *host = slot->host;
> + struct dw_mci_exynos_priv_data *priv = host->priv;
> struct mmc_host *mmc = slot->mmc;
> u8 start_smpl, smpl, candiates = 0;
> s8 found = -1;
> @@ -395,14 +482,27 @@ static int dw_mci_exynos_execute_tuning(struct dw_mci_slot *slot)
> } while (start_smpl != smpl);
>
> found = dw_mci_exynos_get_best_clksmpl(candiates);
> - if (found >= 0)
> + if (found >= 0) {
> dw_mci_exynos_set_clksmpl(host, found);
> - else
> + priv->tuned_sample = found;
> + } else {
> ret = -EIO;
> + }
>
> return ret;
> }
>
> +int dw_mci_exynos_prepare_hs400_tuning(struct dw_mci *host,
> + struct mmc_ios *ios)
> +{
> + struct dw_mci_exynos_priv_data *priv = host->priv;
> +
> + dw_mci_exynos_set_clksel_timing(host, priv->hs400_timing);
> + dw_mci_exynos_adjust_clock(host, (ios->clock) << 1);
> +
> + return 0;
> +}
> +
> /* Common capabilities of Exynos4/Exynos5 SoC */
> static unsigned long exynos_dwmmc_caps[4] = {
> MMC_CAP_1_8V_DDR | MMC_CAP_8_BIT_DATA | MMC_CAP_CMD23,
> @@ -419,6 +519,7 @@ static const struct dw_mci_drv_data exynos_drv_data = {
> .set_ios = dw_mci_exynos_set_ios,
> .parse_dt = dw_mci_exynos_parse_dt,
> .execute_tuning = dw_mci_exynos_execute_tuning,
> + .prepare_hs400_tuning = dw_mci_exynos_prepare_hs400_tuning,
> };
>
> static const struct of_device_id dw_mci_exynos_match[] = {
> diff --git a/drivers/mmc/host/dw_mmc-exynos.h b/drivers/mmc/host/dw_mmc-exynos.h
> index c04ecef..e7faffe 100644
> --- a/drivers/mmc/host/dw_mmc-exynos.h
> +++ b/drivers/mmc/host/dw_mmc-exynos.h
> @@ -12,21 +12,36 @@
> #ifndef _DW_MMC_EXYNOS_H_
> #define _DW_MMC_EXYNOS_H_
>
> -/* Extended Register's Offset */
> #define SDMMC_CLKSEL 0x09C
> #define SDMMC_CLKSEL64 0x0A8
>
> +/* Extended Register's Offset */
> +#define SDMMC_HS400_DQS_EN 0x180
> +#define SDMMC_HS400_ASYNC_FIFO_CTRL 0x184
> +#define SDMMC_HS400_DLINE_CTRL 0x188
> +
> /* CLKSEL register defines */
> #define SDMMC_CLKSEL_CCLK_SAMPLE(x) (((x) & 7) << 0)
> #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_UP_SAMPLE(x, y) (((x) & ~SDMMC_CLKSEL_CCLK_SAMPLE(7)) |\
> + SDMMC_CLKSEL_CCLK_SAMPLE(y))
> #define SDMMC_CLKSEL_TIMING(x, y, z) (SDMMC_CLKSEL_CCLK_SAMPLE(x) | \
> SDMMC_CLKSEL_CCLK_DRIVE(y) | \
> SDMMC_CLKSEL_CCLK_DIVIDER(z))
> +#define SDMMC_CLKSEL_TIMING_MASK SDMMC_CLKSEL_TIMING(0x7, 0x7, 0x7)
> #define SDMMC_CLKSEL_WAKEUP_INT BIT(11)
>
> +/* HS400 control defines */
> +#define DATA_STROBE_EN BIT(0)
Add comment "xxx register defines."
> +#define AXI_NON_BLOCKING_WR BIT(7)
I can't find this bit and comment..where?
> +
> +/* Delay Line Control defines */
> +#define DQS_CTRL_RD_DELAY(x, y) (((x) & ~0x3FF) | ((y) & 0x3FF))
I'm not understanding this define... clear and set?
Best Regards,
Jaehoon Chung
> +#define DQS_CTRL_GET_RD_DELAY(x) ((x) & 0x3FF)
> +
> /* Protector Register */
> #define SDMMC_EMMCP_BASE 0x1000
> #define SDMMC_MPSECURITY (SDMMC_EMMCP_BASE + 0x0010)
> diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
> index 2e8abc8..43a3a5b 100644
> --- a/drivers/mmc/host/dw_mmc.c
> +++ b/drivers/mmc/host/dw_mmc.c
> @@ -1084,7 +1084,8 @@ static void dw_mci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
> regs = mci_readl(slot->host, UHS_REG);
>
> /* DDR mode set */
> - if (ios->timing == MMC_TIMING_MMC_DDR52)
> + if (ios->timing == MMC_TIMING_MMC_DDR52 ||
> + ios->timing == MMC_TIMING_MMC_HS400)
> regs |= ((0x1 << slot->id) << 16);
> else
> regs &= ~((0x1 << slot->id) << 16);
> @@ -1321,6 +1322,18 @@ static int dw_mci_execute_tuning(struct mmc_host *mmc, u32 opcode)
> return err;
> }
>
> +int dw_mci_prepare_hs400_tuning(struct mmc_host *mmc, struct mmc_ios *ios)
> +{
> + struct dw_mci_slot *slot = mmc_priv(mmc);
> + struct dw_mci *host = slot->host;
> + const struct dw_mci_drv_data *drv_data = host->drv_data;
> +
> + if (drv_data && drv_data->prepare_hs400_tuning)
> + return drv_data->prepare_hs400_tuning(host, ios);
> +
> + return 0;
> +}
> +
> static const struct mmc_host_ops dw_mci_ops = {
> .request = dw_mci_request,
> .pre_req = dw_mci_pre_req,
> @@ -1333,6 +1346,7 @@ static const struct mmc_host_ops dw_mci_ops = {
> .card_busy = dw_mci_card_busy,
> .start_signal_voltage_switch = dw_mci_switch_voltage,
> .init_card = dw_mci_init_card,
> + .prepare_hs400_tuning = dw_mci_prepare_hs400_tuning,
> };
>
> static void dw_mci_request_end(struct dw_mci *host, struct mmc_request *mrq)
> diff --git a/drivers/mmc/host/dw_mmc.h b/drivers/mmc/host/dw_mmc.h
> index 18c4afe..d239867 100644
> --- a/drivers/mmc/host/dw_mmc.h
> +++ b/drivers/mmc/host/dw_mmc.h
> @@ -271,5 +271,7 @@ struct dw_mci_drv_data {
> void (*set_ios)(struct dw_mci *host, struct mmc_ios *ios);
> int (*parse_dt)(struct dw_mci *host);
> int (*execute_tuning)(struct dw_mci_slot *slot);
> + int (*prepare_hs400_tuning)(struct dw_mci *host,
> + struct mmc_ios *ios);
> };
> #endif /* _DW_MMC_H_ */
>
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