[PATCH v3 2/4] mmc: dw_mmc: exynos: support eMMC's HS400 mode
Alim Akhtar
alim.akhtar at gmail.com
Thu Jan 8 06:17:15 PST 2015
Hi Jaehoon,
On Thu, Jan 8, 2015 at 7:16 AM, Jaehoon Chung <jh80.chung at samsung.com> wrote:
> 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."
>
Ok, will add
>> +#define AXI_NON_BLOCKING_WR BIT(7)
>
> I can't find this bit and comment..where?
>
This is Bit[7] of RCLK_EN register.
>> +
>> +/* Delay Line Control defines */
>> +#define DQS_CTRL_RD_DELAY(x, y) (((x) & ~0x3FF) | ((y) & 0x3FF))
>
> I'm not understanding this define... clear and set?
>
yes, clear default and set the one pass from Device Tree.
> 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_ */
>>
>
--
Regards,
Alim
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