mmc: sdhci-esdhc-imx: add tuning-step setting support
tuning-step is the delay cell steps in tuning procedure. The default value
of tuning-step is 1. Some boards or cards need another value to pass the
tuning procedure. For example, imx7d-sdb board need the tuning-step value
as 2, otherwise it can't pass the tuning procedure.
So this patch add the tuning-step setting in driver, so that user can set
the tuning-step value in dts.
Signed-off-by: Haibo Chen <haibo.chen@freescale.com>
Acked-by: Dong Aisheng <aisheng.dong@freescale.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-esdhc-imx.c
index b8b7e88..298551d 100644
--- a/drivers/mmc/host/sdhci-esdhc-imx.c
+++ b/drivers/mmc/host/sdhci-esdhc-imx.c
@@ -75,6 +75,7 @@
#define ESDHC_STD_TUNING_EN (1 << 24)
/* NOTE: the minimum valid tuning start tap for mx6sl is 1 */
#define ESDHC_TUNING_START_TAP 0x1
+#define ESDHC_TUNING_STEP_SHIFT 16
/* pinctrl state */
#define ESDHC_PINCTRL_STATE_100MHZ "state_100mhz"
@@ -474,6 +475,7 @@
} else if (imx_data->socdata->flags & ESDHC_FLAG_STD_TUNING) {
u32 v = readl(host->ioaddr + SDHCI_ACMD12_ERR);
u32 m = readl(host->ioaddr + ESDHC_MIX_CTRL);
+ u32 tuning_ctrl;
if (val & SDHCI_CTRL_TUNED_CLK) {
v |= ESDHC_MIX_CTRL_SMPCLK_SEL;
} else {
@@ -484,6 +486,11 @@
if (val & SDHCI_CTRL_EXEC_TUNING) {
v |= ESDHC_MIX_CTRL_EXE_TUNE;
m |= ESDHC_MIX_CTRL_FBCLK_SEL;
+ tuning_ctrl = readl(host->ioaddr + ESDHC_TUNING_CTRL);
+ tuning_ctrl |= ESDHC_STD_TUNING_EN | ESDHC_TUNING_START_TAP;
+ if (imx_data->boarddata.tuning_step)
+ tuning_ctrl |= imx_data->boarddata.tuning_step << ESDHC_TUNING_STEP_SHIFT;
+ writel(tuning_ctrl, host->ioaddr + ESDHC_TUNING_CTRL);
} else {
v &= ~ESDHC_MIX_CTRL_EXE_TUNE;
}
@@ -963,6 +970,8 @@
if (gpio_is_valid(boarddata->wp_gpio))
boarddata->wp_type = ESDHC_WP_GPIO;
+ of_property_read_u32(np, "fsl,tuning-step", &boarddata->tuning_step);
+
if (of_find_property(np, "no-1-8-v", NULL))
boarddata->support_vsel = false;
else