[PATCH v2 2/2] mmc: host: sunxi: add support for A64 mmc controller
Hans de Goede
hdegoede at redhat.com
Sun Jul 31 07:30:29 PDT 2016
Hi,
On 31-07-16 13:02, 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.
>
> Based on work by Andre Przywara <andre.przywara at arm.com>.
>
> Signed-off-by: Icenowy Zheng <icenowy at aosc.xyz>
Looks good, some minor remarks (see comments inline) after those
are addressed this is ready to be merged IMHO.
> ---
> drivers/mmc/host/sunxi-mmc.c | 106 ++++++++++++++++++++++++++++++++++++-------
> 1 file changed, 90 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/mmc/host/sunxi-mmc.c b/drivers/mmc/host/sunxi-mmc.c
> index 2ec91ce..aa2abf3 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 */
> +
> +
Please drop 1 empty line here.
> #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;
> @@ -232,6 +249,9 @@ struct sunxi_idma_des {
> struct sunxi_mmc_cfg {
> u32 idma_des_size_bits;
> const struct sunxi_mmc_clk_delay *clk_delays;
> +
I would not insert an empty line here.
> + /* does the IP block support autocalibration? */
> + bool can_calibrate;
> };
>
> struct sunxi_mmc_host {
> @@ -657,6 +677,34 @@ 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;
> +
I would add:
if (!host->cfg->can_calibrate)
return 0;
Here; and ...
> + 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);
Add:
/* TODO: enable calibrate on sdc2 SDXC_REG_DS_DL_REG of A64 */
here; and ...
> +
> + return 0;
> +}
> +
> static int sunxi_mmc_clk_set_phase(struct sunxi_mmc_host *host,
> struct mmc_ios *ios, u32 rate)
> {
> @@ -727,9 +775,17 @@ static int sunxi_mmc_clk_set_rate(struct sunxi_mmc_host *host,
> }
> mmc_writel(host, REG_CLKCR, rval);
>
> - ret = sunxi_mmc_clk_set_phase(host, ios, rate);
> - if (ret)
> - return ret;
Keep this as is; and add:
ret = sunxi_mmc_calibrate(host, ios, SDXC_REG_SAMP_DL_REG);
if (ret)
return ret;
Instead of:
> + if (host->cfg->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 {
> + ret = sunxi_mmc_clk_set_phase(host, ios, rate);
> + if (ret)
> + return ret;
> + }
>
> return sunxi_mmc_oclk_onoff(host, 1);
> }
> @@ -982,21 +1038,31 @@ static const struct sunxi_mmc_clk_delay sun9i_mmc_clk_delays[] = {
> static const struct sunxi_mmc_cfg sun4i_a10_cfg = {
> .idma_des_size_bits = 13,
> .clk_delays = NULL,
> + .can_calibrate = false,
> };
>
> static const struct sunxi_mmc_cfg sun5i_a13_cfg = {
> .idma_des_size_bits = 16,
> .clk_delays = NULL,
> + .can_calibrate = false,
> };
>
> static const struct sunxi_mmc_cfg sun7i_a20_cfg = {
> .idma_des_size_bits = 16,
> .clk_delays = sunxi_mmc_clk_delays,
> + .can_calibrate = false,
> };
>
> static const struct sunxi_mmc_cfg sun9i_a80_cfg = {
> .idma_des_size_bits = 16,
> .clk_delays = sun9i_mmc_clk_delays,
> + .can_calibrate = false,
> +};
> +
> +static const struct sunxi_mmc_cfg sun50i_a64_cfg = {
> + .idma_des_size_bits = 16,
> + .clk_delays = NULL,
> + .can_calibrate = true,
> };
>
> static const struct of_device_id sunxi_mmc_of_match[] = {
> @@ -1004,6 +1070,7 @@ static const struct of_device_id sunxi_mmc_of_match[] = {
> { .compatible = "allwinner,sun5i-a13-mmc", .data = &sun5i_a13_cfg },
> { .compatible = "allwinner,sun7i-a20-mmc", .data = &sun7i_a20_cfg },
> { .compatible = "allwinner,sun9i-a80-mmc", .data = &sun9i_a80_cfg },
> + { .compatible = "allwinner,sun50i-a64-mmc", .data = &sun50i_a64_cfg },
> { /* sentinel */ }
> };
> MODULE_DEVICE_TABLE(of, sunxi_mmc_of_match);
Not sure why all the below hunks are here, they certainly do not belong
in this patch; and they are not necessary. As I mentioned in the
commit msg of "mmc: sunxi: sun4i / sun5i do not have sample clocks" :
"Note this patch leaves the clk_prepare_enable() / clk_disable_unprepare()
calls to the sample clks as-is, without adding checks for them being
NULL. All the clk_foo calls accept a NULL clk and will return success when
called with a NULL clk."
So please drop these.
Thanks & Regards,
Hans
> @@ -1071,16 +1138,18 @@ 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->cfg->clk_delays) {
> + 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)) {
> @@ -1107,9 +1176,11 @@ 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->cfg->clk_delays)
> + clk_disable_unprepare(host->clk_sample);
> error_disable_clk_output:
> - clk_disable_unprepare(host->clk_output);
> + if (host->cfg->clk_delays)
> + clk_disable_unprepare(host->clk_output);
> error_disable_clk_mmc:
> clk_disable_unprepare(host->clk_mmc);
> error_disable_clk_ahb:
> @@ -1191,8 +1262,11 @@ static int sunxi_mmc_remove(struct platform_device *pdev)
> if (!IS_ERR(host->reset))
> reset_control_assert(host->reset);
>
> - clk_disable_unprepare(host->clk_sample);
> - clk_disable_unprepare(host->clk_output);
> + if (host->cfg->clk_delays) {
> + clk_disable_unprepare(host->clk_sample);
> + clk_disable_unprepare(host->clk_output);
> + }
> +
> clk_disable_unprepare(host->clk_mmc);
> clk_disable_unprepare(host->clk_ahb);
>
>
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