On 05/10/16 17:40, Ritesh Harjani wrote:
> From: Venkat Gopalakrishnan <venkatg@xxxxxxxxxxxxxx>
>
> The following msm platform specific changes are added to support HS400.
> - Allow tuning for HS400 mode.
> - Configure HS400 timing mode using the VENDOR_SPECIFIC_FUNC register.
>
> Signed-off-by: Venkat Gopalakrishnan <venkatg@xxxxxxxxxxxxxx>
> Signed-off-by: Ritesh Harjani <riteshh@xxxxxxxxxxxxxx>
> ---
> drivers/mmc/host/sdhci-msm.c | 124 +++++++++++++++++++++++++++++++++++++++----
> 1 file changed, 113 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
> index eb1a9e3..612fa82 100644
> --- a/drivers/mmc/host/sdhci-msm.c
> +++ b/drivers/mmc/host/sdhci-msm.c
> @@ -31,6 +31,7 @@
> #define HC_MODE_EN 0x1
> #define CORE_POWER 0x0
> #define CORE_SW_RST BIT(7)
> +#define FF_CLK_SW_RST_DIS BIT(13)
>
> #define CORE_PWRCTL_STATUS 0xdc
> #define CORE_PWRCTL_MASK 0xe0
> @@ -64,11 +65,18 @@
>
> #define CORE_VENDOR_SPEC 0x10c
> #define CORE_CLK_PWRSAVE BIT(1)
> +#define CORE_HC_MCLK_SEL_DFLT (2 << 8)
> +#define CORE_HC_MCLK_SEL_HS400 (3 << 8)
> +#define CORE_HC_MCLK_SEL_MASK (3 << 8)
> +#define CORE_HC_SELECT_IN_EN (1 << 18)
> +#define CORE_HC_SELECT_IN_HS400 (6 << 19)
> +#define CORE_HC_SELECT_IN_MASK (7 << 19)
>
> #define CORE_VENDOR_SPEC_CAPABILITIES0 0x11c
>
> #define TCXO_FREQ 19200000
> #define SDHCI_MSM_MIN_CLOCK 400000
> +#define CORE_FREQ_100MHZ (100 * 1000 * 1000)
>
> #define CDR_SELEXT_SHIFT 20
> #define CDR_SELEXT_MASK (0xf << CDR_SELEXT_SHIFT)
> @@ -87,6 +95,8 @@ struct sdhci_msm_host {
> u32 clk_rate;
> struct mmc_host *mmc;
> bool use_14lpp_dll_reset;
> + bool tuning_done;
> + bool calibration_done;
> };
>
> /* Platform specific tuning */
> @@ -175,8 +185,8 @@ out:
> * Find out the greatest range of consecuitive selected
> * DLL clock output phases that can be used as sampling
> * setting for SD3.0 UHS-I card read operation (in SDR104
> - * timing mode) or for eMMC4.5 card read operation (in HS200
> - * timing mode).
> + * timing mode) or for eMMC4.5 card read operation (in
> + * HS400/HS200 timing mode).
> * Select the 3/4 of the range and configure the DLL with the
> * selected DLL clock output phase.
> */
> @@ -428,9 +438,10 @@ static int sdhci_msm_execute_tuning(struct sdhci_host *host, u32 opcode)
> * Tuning is required for SDR104, HS200 and HS400 cards and
> * if clock frequency is greater than 100MHz in these modes.
> */
> - if (host->clock <= 100 * 1000 * 1000 ||
> - !((ios.timing == MMC_TIMING_MMC_HS200) ||
> - (ios.timing == MMC_TIMING_UHS_SDR104)))
> + if (host->clock <= CORE_FREQ_100MHZ ||
> + !((ios.timing == MMC_TIMING_MMC_HS400) ||
> + (ios.timing == MMC_TIMING_MMC_HS200) ||
> + (ios.timing == MMC_TIMING_UHS_SDR104)))
Don't need () around ios.timing == MMC_TIMING_MMC_HS400 etc
> return 0;
>
> retry:
> @@ -488,7 +499,10 @@ static void sdhci_msm_set_uhs_signaling(struct sdhci_host *host,
> unsigned int uhs)
> {
> struct mmc_host *mmc = host->mmc;
> + struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> + struct sdhci_msm_host *msm_host = sdhci_pltfm_priv(pltfm_host);
> u16 ctrl_2;
> + u32 config;
>
> ctrl_2 = sdhci_readw(host, SDHCI_HOST_CONTROL2);
> /* Select Bus Speed Mode for host */
> @@ -503,6 +517,7 @@ static void sdhci_msm_set_uhs_signaling(struct sdhci_host *host,
> case MMC_TIMING_UHS_SDR50:
> ctrl_2 |= SDHCI_CTRL_UHS_SDR50;
> break;
> + case MMC_TIMING_MMC_HS400:
> case MMC_TIMING_MMC_HS200:
> case MMC_TIMING_UHS_SDR104:
> ctrl_2 |= SDHCI_CTRL_UHS_SDR104;
> @@ -519,11 +534,33 @@ static void sdhci_msm_set_uhs_signaling(struct sdhci_host *host,
> * provide feedback clock, the mode selection can be any value less
> * than 3'b011 in bits [2:0] of HOST CONTROL2 register.
> */
> - if (host->clock <= 100000000 &&
> - (uhs == MMC_TIMING_MMC_HS400 ||
> - uhs == MMC_TIMING_MMC_HS200 ||
> - uhs == MMC_TIMING_UHS_SDR104))
> - ctrl_2 &= ~SDHCI_CTRL_UHS_MASK;
> + if (host->clock <= CORE_FREQ_100MHZ) {
> + if ((uhs == MMC_TIMING_MMC_HS400) ||
> + (uhs == MMC_TIMING_MMC_HS200) ||
> + (uhs == MMC_TIMING_UHS_SDR104))
> + ctrl_2 &= ~SDHCI_CTRL_UHS_MASK;
> + /*
> + * Make sure DLL is disabled when not required
> + *
> + * Write 1 to DLL_RST bit of DLL_CONFIG register
> + */
> + config = readl_relaxed(host->ioaddr + CORE_DLL_CONFIG);
> + config |= CORE_DLL_RST;
> + writel_relaxed(config, host->ioaddr + CORE_DLL_CONFIG);
> +
> + /* Write 1 to DLL_PDN bit of DLL_CONFIG register */
> + config = readl_relaxed(host->ioaddr + CORE_DLL_CONFIG);
> + config |= CORE_DLL_PDN;
> + writel_relaxed(config, host->ioaddr + CORE_DLL_CONFIG);
> +
> + wmb(); /* drain writebuffer */
Memory barrier could use more explanation.
> +
> + /*
> + * The DLL needs to be restored and CDCLP533 recalibrated
> + * when the clock frequency is set back to 400MHz.
> + */
> + msm_host->calibration_done = false;
> + }
>
> dev_dbg(mmc_dev(mmc), "%s: clock=%u uhs=%u ctrl_2=0x%x\n",
> mmc_hostname(host->mmc), host->clock, uhs, ctrl_2);
> @@ -670,7 +707,7 @@ static void sdhci_msm_set_clock(struct sdhci_host *host, unsigned int clock)
> struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> struct sdhci_msm_host *msm_host = sdhci_pltfm_priv(pltfm_host);
> struct mmc_ios curr_ios = host->mmc->ios;
> - u32 msm_clock;
> + u32 msm_clock, config;
> int rc;
>
> if (!clock)
> @@ -691,6 +728,66 @@ static void sdhci_msm_set_clock(struct sdhci_host *host, unsigned int clock)
> }
> msm_clock = sdhci_msm_get_msm_clk_rate(host, clock);
>
> + /*
> + * In general all timing modes are controlled via UHS mode select in
> + * Host Control2 register. eMMC specific HS200/HS400 doesn't have
> + * their respective modes defined here, hence we use these values.
> + *
> + * HS200 - SDR104 (Since they both are equivalent in functionality)
> + * HS400 - This involves multiple configurations
> + * Initially SDR104 - when tuning is required as HS200
> + * Then when switching to DDR @ 400MHz (HS400) we use
> + * the vendor specific HC_SELECT_IN to control the mode.
> + *
> + * In addition to controlling the modes we also need to select the
> + * correct input clock for DLL depending on the mode.
> + *
> + * HS400 - divided clock (free running MCLK/2)
> + * All other modes - default (free running MCLK)
> + */
> + if (curr_ios.timing == MMC_TIMING_MMC_HS400) {
> + /* Select the divided clock (free running MCLK/2) */
> + config = readl_relaxed(host->ioaddr + CORE_VENDOR_SPEC);
> + config &= ~CORE_HC_MCLK_SEL_MASK;
> + config |= CORE_HC_MCLK_SEL_HS400;
> +
> + writel_relaxed(config, host->ioaddr + CORE_VENDOR_SPEC);
> + /*
> + * Select HS400 mode using the HC_SELECT_IN from VENDOR SPEC
> + * register
> + */
> + if (msm_host->tuning_done && !msm_host->calibration_done) {
In this patch, tuning_done and calibration_done are never true. Is that
intended?
> + /*
> + * Write 0x6 to HC_SELECT_IN and 1 to HC_SELECT_IN_EN
> + * field in VENDOR_SPEC_FUNC
> + */
> + config = readl_relaxed(host->ioaddr + CORE_VENDOR_SPEC);
> + config |= CORE_HC_SELECT_IN_HS400;
> + config |= CORE_HC_SELECT_IN_EN;
> + writel_relaxed(config, host->ioaddr + CORE_VENDOR_SPEC);
> + }
> + } else {
> + /* Select the default clock (free running MCLK) */
> + config = readl_relaxed(host->ioaddr + CORE_VENDOR_SPEC);
> + config &= ~CORE_HC_MCLK_SEL_MASK;
> + config |= CORE_HC_MCLK_SEL_DFLT;
> + writel_relaxed(config, host->ioaddr + CORE_VENDOR_SPEC);
> +
> + /*
> + * Disable HC_SELECT_IN to be able to use the UHS mode select
> + * configuration from Host Control2 register for all other
> + * modes.
> + *
> + * Write 0 to HC_SELECT_IN and HC_SELECT_IN_EN field
> + * in VENDOR_SPEC_FUNC
> + */
> + config = readl_relaxed(host->ioaddr + CORE_VENDOR_SPEC);
> + config &= ~CORE_HC_SELECT_IN_EN;
> + config &= ~CORE_HC_SELECT_IN_MASK;
> + writel_relaxed(config, host->ioaddr + CORE_VENDOR_SPEC);
> + }
> + wmb(); /* drain writebuffer */
Memory barrier could use more explanation.
> +
> if ((msm_clock != msm_host->clk_rate) && msm_host->clk_table) {
> rc = clk_set_rate(msm_host->clk, msm_clock);
> if (rc) {
> @@ -876,6 +973,11 @@ static int sdhci_msm_probe(struct platform_device *pdev)
> /* Set HC_MODE_EN bit in HC_MODE register */
> writel_relaxed(HC_MODE_EN, (msm_host->core_mem + CORE_HC_MODE));
>
> + /* Set FF_CLK_SW_RST_DIS bit in HC_MODE register */
> + config = readl_relaxed(msm_host->core_mem + CORE_HC_MODE);
> + config |= FF_CLK_SW_RST_DIS;
> + writel_relaxed(config, msm_host->core_mem + CORE_HC_MODE);
> +
> host_version = readw_relaxed((host->ioaddr + SDHCI_HOST_VERSION));
> dev_dbg(&pdev->dev, "Host Version: 0x%x Vendor Version 0x%x\n",
> host_version, ((host_version & SDHCI_VENDOR_VER_MASK) >>
>
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
