Before, we used syscon to achieve tuning, but the actual measurement showed little effect, so the tuning implementation was modified here, and it was realized by reading and writing the UHS_REG_EXT register. Signed-off-by: William Qiu <william.qiu@xxxxxxxxxxxxxxxx> --- drivers/mmc/host/dw_mmc-starfive.c | 131 ++++++++--------------------- 1 file changed, 37 insertions(+), 94 deletions(-) diff --git a/drivers/mmc/host/dw_mmc-starfive.c b/drivers/mmc/host/dw_mmc-starfive.c index fd05a648a8bb..593c995e49f5 100644 --- a/drivers/mmc/host/dw_mmc-starfive.c +++ b/drivers/mmc/host/dw_mmc-starfive.c @@ -20,14 +20,6 @@ #define ALL_INT_CLR 0x1ffff #define MAX_DELAY_CHAIN 32 -struct starfive_priv { - struct device *dev; - struct regmap *reg_syscon; - u32 syscon_offset; - u32 syscon_shift; - u32 syscon_mask; -}; - static void dw_mci_starfive_set_ios(struct dw_mci *host, struct mmc_ios *ios) { int ret; @@ -44,117 +36,68 @@ static void dw_mci_starfive_set_ios(struct dw_mci *host, struct mmc_ios *ios) } } +static void dw_mci_starfive_hs_set_bits(struct dw_mci *host, u32 smpl_phase) +{ + /* change driver phase and sample phase */ + u32 mask = 0x1f; + u32 reg_value; + + reg_value = mci_readl(host, UHS_REG_EXT); + + /* In UHS_REG_EXT, only 5 bits valid in DRV_PHASE and SMPL_PHASE */ + reg_value &= ~(mask << 16); + reg_value |= (smpl_phase << 16); + mci_writel(host, UHS_REG_EXT, reg_value); + + /* We should delay 1ms wait for timing setting finished. */ + mdelay(1); +} + static int dw_mci_starfive_execute_tuning(struct dw_mci_slot *slot, u32 opcode) { static const int grade = MAX_DELAY_CHAIN; struct dw_mci *host = slot->host; - struct starfive_priv *priv = host->priv; - int rise_point = -1, fall_point = -1; - int err, prev_err = 0; + int err = -1; + int smpl_phase, smpl_raise = -1, smpl_fall = -1; int i; - bool found = 0; - u32 regval; - - /* - * Use grade as the max delay chain, and use the rise_point and - * fall_point to ensure the best sampling point of a data input - * signals. - */ + for (i = 0; i < grade; i++) { - regval = i << priv->syscon_shift; - err = regmap_update_bits(priv->reg_syscon, priv->syscon_offset, - priv->syscon_mask, regval); - if (err) - return err; + smpl_phase = i; + dw_mci_starfive_hs_set_bits(host, smpl_phase); mci_writel(host, RINTSTS, ALL_INT_CLR); err = mmc_send_tuning(slot->mmc, opcode, NULL); - if (!err) - found = 1; - - if (i > 0) { - if (err && !prev_err) - fall_point = i - 1; - if (!err && prev_err) - rise_point = i; - } - if (rise_point != -1 && fall_point != -1) - goto tuning_out; - - prev_err = err; - err = 0; - } - -tuning_out: - if (found) { - if (rise_point == -1) - rise_point = 0; - if (fall_point == -1) - fall_point = grade - 1; - if (fall_point < rise_point) { - if ((rise_point + fall_point) > - (grade - 1)) - i = fall_point / 2; - else - i = (rise_point + grade - 1) / 2; - } else { - i = (rise_point + fall_point) / 2; + if (!err && smpl_raise < 0) { + smpl_raise = i; + } else if (err && smpl_raise >= 0) { + smpl_fall = i - 1; + break; } + } - regval = i << priv->syscon_shift; - err = regmap_update_bits(priv->reg_syscon, priv->syscon_offset, - priv->syscon_mask, regval); - if (err) - return err; - mci_writel(host, RINTSTS, ALL_INT_CLR); + if (i >= grade && smpl_raise >= 0) + smpl_fall = grade - 1; - dev_info(host->dev, "Found valid delay chain! use it [delay=%d]\n", i); - } else { + if (smpl_raise < 0) { dev_err(host->dev, "No valid delay chain! use default\n"); + dw_mci_starfive_hs_set_bits(host, 0); err = -EINVAL; + } else { + smpl_phase = (smpl_raise + smpl_fall) / 2; + dw_mci_starfive_hs_set_bits(host, smpl_phase); + dev_dbg(host->dev, "Found valid delay chain! use it [delay=%d]\n", smpl_phase); + err = 0; } mci_writel(host, RINTSTS, ALL_INT_CLR); return err; } -static int dw_mci_starfive_parse_dt(struct dw_mci *host) -{ - struct of_phandle_args args; - struct starfive_priv *priv; - int ret; - - priv = devm_kzalloc(host->dev, sizeof(*priv), GFP_KERNEL); - if (!priv) - return -ENOMEM; - - ret = of_parse_phandle_with_fixed_args(host->dev->of_node, - "starfive,sysreg", 3, 0, &args); - if (ret) { - dev_err(host->dev, "Failed to parse starfive,sysreg\n"); - return -EINVAL; - } - - priv->reg_syscon = syscon_node_to_regmap(args.np); - of_node_put(args.np); - if (IS_ERR(priv->reg_syscon)) - return PTR_ERR(priv->reg_syscon); - - priv->syscon_offset = args.args[0]; - priv->syscon_shift = args.args[1]; - priv->syscon_mask = args.args[2]; - - host->priv = priv; - - return 0; -} - static const struct dw_mci_drv_data starfive_data = { .common_caps = MMC_CAP_CMD23, .set_ios = dw_mci_starfive_set_ios, - .parse_dt = dw_mci_starfive_parse_dt, .execute_tuning = dw_mci_starfive_execute_tuning, }; -- 2.34.1