[PATCH 2/2] mmc: host: sunxi: add support for A64 mmc controller

Hans de Goede hdegoede at redhat.com
Sat Jul 30 04:40:42 PDT 2016


Hi,

On 30-07-16 13:35, Icenowy Zheng wrote:
>
>
> 30.07.2016, 18:30, "Hans de Goede" <hdegoede at redhat.com>:
>> Hi,
>>
>> On 30-07-16 11:36, Icenowy Zheng wrote:
>>>  A64 SoC features a MMC controller which need only the mod clock, and can
>>>  calibrate delay by itself. This patch adds support for the new MMC
>>>  controller IP core.
>>>
>>>  Signed-off-by: Icenowy Zheng <icenowy at aosc.xyz>
>>
>> Cool stuff, thanks for your work on this!
>>
>>>  ---
>>>   drivers/mmc/host/sunxi-mmc.c | 166 +++++++++++++++++++++++++++++++------------
>>>   1 file changed, 122 insertions(+), 44 deletions(-)
>>>
>>>  diff --git a/drivers/mmc/host/sunxi-mmc.c b/drivers/mmc/host/sunxi-mmc.c
>>>  index 2ee4c21..ac56bcf 100644
>>>  --- a/drivers/mmc/host/sunxi-mmc.c
>>>  +++ b/drivers/mmc/host/sunxi-mmc.c
>>>  @@ -72,6 +72,14 @@
>>>   #define SDXC_REG_CHDA (0x90)
>>>   #define SDXC_REG_CBDA (0x94)
>>>
>>>  +/* New registers introduced in A64 */
>>>  +#define SDXC_REG_A12A 0x058 /* SMC Auto Command 12 Register */
>>>  +#define SDXC_REG_SD_NTSR 0x05C /* SMC New Timing Set Register */
>>>  +#define SDXC_REG_DRV_DL 0x140 /* Drive Delay Control Register */
>>>  +#define SDXC_REG_SAMP_DL_REG 0x144 /* SMC sample delay control */
>>>  +#define SDXC_REG_DS_DL_REG 0x148 /* SMC data strobe delay control */
>>>  +
>>>  +
>>>   #define mmc_readl(host, reg) \
>>>           readl((host)->reg_base + SDXC_##reg)
>>>   #define mmc_writel(host, reg, value) \
>>>  @@ -217,6 +225,15 @@
>>>   #define SDXC_CLK_50M_DDR 3
>>>   #define SDXC_CLK_50M_DDR_8BIT 4
>>>
>>>  +#define SDXC_2X_TIMING_MODE BIT(31)
>>>  +
>>>  +#define SDXC_CAL_START BIT(15)
>>>  +#define SDXC_CAL_DONE BIT(14)
>>>  +#define SDXC_CAL_DL_SHIFT 8
>>>  +#define SDXC_CAL_DL_SW_EN BIT(7)
>>>  +#define SDXC_CAL_DL_SW_SHIFT 0
>>>  +#define SDXC_CAL_DL_MASK 0x3f
>>>  +
>>>   struct sunxi_mmc_clk_delay {
>>>           u32 output;
>>>           u32 sample;
>>>  @@ -261,6 +278,9 @@ struct sunxi_mmc_host {
>>>
>>>           /* vqmmc */
>>>           bool vqmmc_enabled;
>>>  +
>>>  + /* does the IP block support autocalibration? */
>>>  + bool can_calibrate;
>>>   };
>>>
>>>   static int sunxi_mmc_reset_host(struct sunxi_mmc_host *host)
>>>  @@ -653,10 +673,66 @@ static int sunxi_mmc_oclk_onoff(struct sunxi_mmc_host *host, u32 oclk_en)
>>>           return 0;
>>>   }
>>>
>>>  +static int sunxi_mmc_calibrate(struct sunxi_mmc_host *host,
>>>  + struct mmc_ios *ios, int reg_off)
>>>  +{
>>>  + u32 reg = readl(host->reg_base + reg_off);
>>>  + u32 delay;
>>>  +
>>>  + reg &= ~(SDXC_CAL_DL_MASK << SDXC_CAL_DL_SW_SHIFT);
>>>  + reg &= ~SDXC_CAL_DL_SW_EN;
>>>  +
>>>  + writel(reg | SDXC_CAL_START, host->reg_base + reg_off);
>>>  +
>>>  + dev_dbg(mmc_dev(host->mmc), "calibration started\n");
>>>  +
>>>  + while (!((reg = readl(host->reg_base + reg_off)) & SDXC_CAL_DONE))
>>>  + cpu_relax();
>>>  +
>>>  + delay = (reg >> SDXC_CAL_DL_SHIFT) & SDXC_CAL_DL_MASK;
>>>  +
>>>  + reg &= ~SDXC_CAL_START;
>>>  + reg |= (delay << SDXC_CAL_DL_SW_SHIFT) | SDXC_CAL_DL_SW_EN;
>>>  +
>>>  + writel(reg, host->reg_base + reg_off);
>>>  +
>>>  + dev_dbg(mmc_dev(host->mmc), "calibration ended, res is 0x%x\n", reg);
>>>  +
>>>  + return 0;
>>>  +}
>>>  +
>>>  +static int sunxi_mmc_determine_delays(struct sunxi_mmc_host *host,
>>>  + struct mmc_ios *ios, int rate)
>>>  +{
>>>  + int index;
>>>  +
>>>  + if (rate <= 400000) {
>>>  + index = SDXC_CLK_400K;
>>>  + } else if (rate <= 25000000) {
>>>  + index = SDXC_CLK_25M;
>>>  + } else if (rate <= 52000000) {
>>>  + if (ios->timing != MMC_TIMING_UHS_DDR50 &&
>>>  + ios->timing != MMC_TIMING_MMC_DDR52) {
>>>  + index = SDXC_CLK_50M;
>>>  + } else if (ios->bus_width == MMC_BUS_WIDTH_8) {
>>>  + index = SDXC_CLK_50M_DDR_8BIT;
>>>  + } else {
>>>  + index = SDXC_CLK_50M_DDR;
>>>  + }
>>>  + } else {
>>>  + return -EINVAL;
>>>  + }
>>>  +
>>>  + clk_set_phase(host->clk_sample, host->clk_delays[index].sample);
>>>  + clk_set_phase(host->clk_output, host->clk_delays[index].output);
>>>  +
>>>  + return 0;
>>>  +}
>>>  +
>>
>> The factoring out of this into a function really should be done in
>> a separate preparation patch, that will also make the patch making
>> the actual functional changes much easier to read.
>
> Thanks.
>
> And I forgot add the infomation that the patch is based on apritzel's
> work...
>
> I will soon send a PATCH v2.
>
> If your A10/13 mmc clock driver can be merged ASAP, then I will be
> able to drop some bits from the patch.

I need to do a v2 of that, I will hopefully send that out today.

Regards,

Hans




>
>>
>> Regards,
>>
>> Hans
>>
>>>   static int sunxi_mmc_clk_set_rate(struct sunxi_mmc_host *host,
>>>                                     struct mmc_ios *ios)
>>>   {
>>>  - u32 rate, oclk_dly, rval, sclk_dly;
>>>  + u32 rate, rval;
>>>           u32 clock = ios->clock;
>>>           int ret;
>>>
>>>  @@ -692,32 +768,18 @@ static int sunxi_mmc_clk_set_rate(struct sunxi_mmc_host *host,
>>>           }
>>>           mmc_writel(host, REG_CLKCR, rval);
>>>
>>>  - /* determine delays */
>>>  - if (rate <= 400000) {
>>>  - oclk_dly = host->clk_delays[SDXC_CLK_400K].output;
>>>  - sclk_dly = host->clk_delays[SDXC_CLK_400K].sample;
>>>  - } else if (rate <= 25000000) {
>>>  - oclk_dly = host->clk_delays[SDXC_CLK_25M].output;
>>>  - sclk_dly = host->clk_delays[SDXC_CLK_25M].sample;
>>>  - } else if (rate <= 52000000) {
>>>  - if (ios->timing != MMC_TIMING_UHS_DDR50 &&
>>>  - ios->timing != MMC_TIMING_MMC_DDR52) {
>>>  - oclk_dly = host->clk_delays[SDXC_CLK_50M].output;
>>>  - sclk_dly = host->clk_delays[SDXC_CLK_50M].sample;
>>>  - } else if (ios->bus_width == MMC_BUS_WIDTH_8) {
>>>  - oclk_dly = host->clk_delays[SDXC_CLK_50M_DDR_8BIT].output;
>>>  - sclk_dly = host->clk_delays[SDXC_CLK_50M_DDR_8BIT].sample;
>>>  - } else {
>>>  - oclk_dly = host->clk_delays[SDXC_CLK_50M_DDR].output;
>>>  - sclk_dly = host->clk_delays[SDXC_CLK_50M_DDR].sample;
>>>  - }
>>>  + if (host->can_calibrate) {
>>>  + ret = sunxi_mmc_calibrate(host, ios, SDXC_REG_SAMP_DL_REG);
>>>  + if (ret)
>>>  + return ret;
>>>  +
>>>  + /* TODO: enable calibrate on sdc2 SDXC_REG_DS_DL_REG of A64 */
>>>           } else {
>>>  - return -EINVAL;
>>>  + ret = sunxi_mmc_determine_delays(host, ios, rate);
>>>  + if (ret)
>>>  + return ret;
>>>           }
>>>
>>>  - clk_set_phase(host->clk_sample, sclk_dly);
>>>  - clk_set_phase(host->clk_output, oclk_dly);
>>>  -
>>>           return sunxi_mmc_oclk_onoff(host, 1);
>>>   }
>>>
>>>  @@ -942,6 +1004,7 @@ static const struct of_device_id sunxi_mmc_of_match[] = {
>>>           { .compatible = "allwinner,sun4i-a10-mmc", },
>>>           { .compatible = "allwinner,sun5i-a13-mmc", },
>>>           { .compatible = "allwinner,sun9i-a80-mmc", },
>>>  + { .compatible = "allwinner,sun50i-a64-mmc", },
>>>           { /* sentinel */ }
>>>   };
>>>   MODULE_DEVICE_TABLE(of, sunxi_mmc_of_match);
>>>  @@ -990,6 +1053,11 @@ static int sunxi_mmc_resource_request(struct sunxi_mmc_host *host,
>>>           else
>>>                   host->clk_delays = sunxi_mmc_clk_delays;
>>>
>>>  + if (of_device_is_compatible(np, "allwinner,sun50i-a64-mmc"))
>>>  + host->can_calibrate = true;
>>>  + else
>>>  + host->can_calibrate = false;
>>>  +
>>>           ret = mmc_regulator_get_supply(host->mmc);
>>>           if (ret) {
>>>                   if (ret != -EPROBE_DEFER)
>>>  @@ -1014,16 +1082,22 @@ static int sunxi_mmc_resource_request(struct sunxi_mmc_host *host,
>>>                   return PTR_ERR(host->clk_mmc);
>>>           }
>>>
>>>  - host->clk_output = devm_clk_get(&pdev->dev, "output");
>>>  - if (IS_ERR(host->clk_output)) {
>>>  - dev_err(&pdev->dev, "Could not get output clock\n");
>>>  - return PTR_ERR(host->clk_output);
>>>  - }
>>>  + /* self-calibrate version of the IP block needs no output/sample */
>>>  + if (!host->can_calibrate) {
>>>  + host->clk_output = devm_clk_get(&pdev->dev, "output");
>>>  + if (IS_ERR(host->clk_output)) {
>>>  + dev_err(&pdev->dev, "Could not get output clock\n");
>>>  + return PTR_ERR(host->clk_output);
>>>  + }
>>>
>>>  - host->clk_sample = devm_clk_get(&pdev->dev, "sample");
>>>  - if (IS_ERR(host->clk_sample)) {
>>>  - dev_err(&pdev->dev, "Could not get sample clock\n");
>>>  - return PTR_ERR(host->clk_sample);
>>>  + host->clk_sample = devm_clk_get(&pdev->dev, "sample");
>>>  + if (IS_ERR(host->clk_sample)) {
>>>  + dev_err(&pdev->dev, "Could not get sample clock\n");
>>>  + return PTR_ERR(host->clk_sample);
>>>  + }
>>>  + } else {
>>>  + host->clk_sample = NULL;
>>>  + host->clk_output = NULL;
>>>           }
>>>
>>>           host->reset = devm_reset_control_get_optional(&pdev->dev, "ahb");
>>>  @@ -1042,16 +1116,18 @@ static int sunxi_mmc_resource_request(struct sunxi_mmc_host *host,
>>>                   goto error_disable_clk_ahb;
>>>           }
>>>
>>>  - ret = clk_prepare_enable(host->clk_output);
>>>  - if (ret) {
>>>  - dev_err(&pdev->dev, "Enable output clk err %d\n", ret);
>>>  - goto error_disable_clk_mmc;
>>>  - }
>>>  + if (!host->can_calibrate) {
>>>  + ret = clk_prepare_enable(host->clk_output);
>>>  + if (ret) {
>>>  + dev_err(&pdev->dev, "Enable output clk err %d\n", ret);
>>>  + goto error_disable_clk_mmc;
>>>  + }
>>>
>>>  - ret = clk_prepare_enable(host->clk_sample);
>>>  - if (ret) {
>>>  - dev_err(&pdev->dev, "Enable sample clk err %d\n", ret);
>>>  - goto error_disable_clk_output;
>>>  + ret = clk_prepare_enable(host->clk_sample);
>>>  + if (ret) {
>>>  + dev_err(&pdev->dev, "Enable sample clk err %d\n", ret);
>>>  + goto error_disable_clk_output;
>>>  + }
>>>           }
>>>
>>>           if (!IS_ERR(host->reset)) {
>>>  @@ -1078,9 +1154,11 @@ error_assert_reset:
>>>           if (!IS_ERR(host->reset))
>>>                   reset_control_assert(host->reset);
>>>   error_disable_clk_sample:
>>>  - clk_disable_unprepare(host->clk_sample);
>>>  + if (!host->can_calibrate)
>>>  + clk_disable_unprepare(host->clk_sample);
>>>   error_disable_clk_output:
>>>  - clk_disable_unprepare(host->clk_output);
>>>  + if (!host->can_calibrate)
>>>  + clk_disable_unprepare(host->clk_output);
>>>   error_disable_clk_mmc:
>>>           clk_disable_unprepare(host->clk_mmc);
>>>   error_disable_clk_ahb:



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