From f4b297bbfde3ab53e5682ff779a13c61c6e12b37 Mon Sep 17 00:00:00 2001 From: Ashok Reddy Soma Date: Fri, 23 Oct 2020 04:59:01 -0600 Subject: [PATCH] mmc: zynq_sdhci: Set tapdelays based on clk phase delays Define and use functions for setting input and output tapdelays based on clk phase delays. Signed-off-by: Ashok Reddy Soma Signed-off-by: Michal Simek Reviewed-by: Peng Fan Reviewed-by: Jaehoon Chung --- drivers/mmc/zynq_sdhci.c | 128 +++++++++++++++++++++++++++++++++++++-- 1 file changed, 123 insertions(+), 5 deletions(-) diff --git a/drivers/mmc/zynq_sdhci.c b/drivers/mmc/zynq_sdhci.c index e69f375cce..8871765711 100644 --- a/drivers/mmc/zynq_sdhci.c +++ b/drivers/mmc/zynq_sdhci.c @@ -166,17 +166,135 @@ static int arasan_sdhci_execute_tuning(struct mmc *mmc, u8 opcode) return 0; } +/** + * sdhci_zynqmp_sdcardclk_set_phase - Set the SD Output Clock Tap Delays + * + * Set the SD Output Clock Tap Delays for Output path + * + * @host: Pointer to the sdhci_host structure. + * @degrees: The clock phase shift between 0 - 359. + * Return: 0 on success and error value on error + */ +static int sdhci_zynqmp_sdcardclk_set_phase(struct sdhci_host *host, + int degrees) +{ + struct arasan_sdhci_priv *priv = dev_get_priv(host->mmc->dev); + struct mmc *mmc = (struct mmc *)host->mmc; + u8 tap_delay, tap_max = 0; + int ret; + int timing = mode2timing[mmc->selected_mode]; + + /* + * This is applicable for SDHCI_SPEC_300 and above + * ZynqMP does not set phase for <=25MHz clock. + * If degrees is zero, no need to do anything. + */ + if (SDHCI_GET_VERSION(host) < SDHCI_SPEC_300 || + timing == MMC_TIMING_LEGACY || + timing == MMC_TIMING_UHS_SDR12 || !degrees) + return 0; + + switch (timing) { + case MMC_TIMING_MMC_HS: + case MMC_TIMING_SD_HS: + case MMC_TIMING_UHS_SDR25: + case MMC_TIMING_UHS_DDR50: + case MMC_TIMING_MMC_DDR52: + /* For 50MHz clock, 30 Taps are available */ + tap_max = 30; + break; + case MMC_TIMING_UHS_SDR50: + /* For 100MHz clock, 15 Taps are available */ + tap_max = 15; + break; + case MMC_TIMING_UHS_SDR104: + case MMC_TIMING_MMC_HS200: + /* For 200MHz clock, 8 Taps are available */ + tap_max = 8; + default: + break; + } + + tap_delay = (degrees * tap_max) / 360; + + arasan_zynqmp_set_tapdelay(priv->deviceid, 0, tap_delay); + + return ret; +} + +/** + * sdhci_zynqmp_sampleclk_set_phase - Set the SD Input Clock Tap Delays + * + * Set the SD Input Clock Tap Delays for Input path + * + * @host: Pointer to the sdhci_host structure. + * @degrees: The clock phase shift between 0 - 359. + * Return: 0 on success and error value on error + */ +static int sdhci_zynqmp_sampleclk_set_phase(struct sdhci_host *host, + int degrees) +{ + struct arasan_sdhci_priv *priv = dev_get_priv(host->mmc->dev); + struct mmc *mmc = (struct mmc *)host->mmc; + u8 tap_delay, tap_max = 0; + int ret; + int timing = mode2timing[mmc->selected_mode]; + + /* + * This is applicable for SDHCI_SPEC_300 and above + * ZynqMP does not set phase for <=25MHz clock. + * If degrees is zero, no need to do anything. + */ + if (SDHCI_GET_VERSION(host) < SDHCI_SPEC_300 || + timing == MMC_TIMING_LEGACY || + timing == MMC_TIMING_UHS_SDR12 || !degrees) + return 0; + + switch (timing) { + case MMC_TIMING_MMC_HS: + case MMC_TIMING_SD_HS: + case MMC_TIMING_UHS_SDR25: + case MMC_TIMING_UHS_DDR50: + case MMC_TIMING_MMC_DDR52: + /* For 50MHz clock, 120 Taps are available */ + tap_max = 120; + break; + case MMC_TIMING_UHS_SDR50: + /* For 100MHz clock, 60 Taps are available */ + tap_max = 60; + break; + case MMC_TIMING_UHS_SDR104: + case MMC_TIMING_MMC_HS200: + /* For 200MHz clock, 30 Taps are available */ + tap_max = 30; + default: + break; + } + + tap_delay = (degrees * tap_max) / 360; + + arasan_zynqmp_set_tapdelay(priv->deviceid, tap_delay, 0); + + return ret; +} + static void arasan_sdhci_set_tapdelay(struct sdhci_host *host) { struct arasan_sdhci_priv *priv = dev_get_priv(host->mmc->dev); + struct arasan_sdhci_clk_data *clk_data = &priv->clk_data; struct mmc *mmc = (struct mmc *)host->mmc; - u8 uhsmode; + struct udevice *dev = mmc->dev; + u8 timing = mode2timing[mmc->selected_mode]; + u32 iclk_phase = clk_data->clk_phase_in[timing]; + u32 oclk_phase = clk_data->clk_phase_out[timing]; - uhsmode = mode2timing[mmc->selected_mode]; + dev_dbg(dev, "%s, host:%s, mode:%d\n", __func__, host->name, timing); - if (uhsmode >= UHS_SDR25_BUS_SPEED) - arasan_zynqmp_set_tapdelay(priv->deviceid, uhsmode, - priv->bank); + if (IS_ENABLED(CONFIG_ARCH_ZYNQMP) && + device_is_compatible(dev, "xlnx,zynqmp-8.9a")) { + sdhci_zynqmp_sampleclk_set_phase(host, iclk_phase); + sdhci_zynqmp_sdcardclk_set_phase(host, oclk_phase); + } } static void arasan_dt_read_clk_phase(struct udevice *dev, unsigned char timing, -- 2.39.5