Hi Hiago,
So, I've dumped the registers using downstream U-Boot and yes, Claude was right.
By default, downstream driver configures the PHY, so the PHY registers
have the following values:
# PHY_TX_RX_DLY
milkv_duo_256m# md.l 0x04310240 1
04310240: 01000100 ....
# PHY_CONFIG
milkv_duo_256m# md.l 0x0431024c 1
0431024c: 00000001 ....
With upstream U-Boot, the same registers are always 0.
Simply setting `PHY_TX_RX_DLY` to `0x01000100` is enough to get
the SD card working.
The attached patch contains the backported PHY configuration from the downstream
driver & upstream kernel. Could you please take a look and check if it
resolves the issue on your side when increasing the clock?
Thank you!
---
drivers/mmc/cv1800b_sdhci.c | 25 +++++++++++++++++++++++++
1 file changed, 25 insertions(+)
diff --git a/drivers/mmc/cv1800b_sdhci.c b/drivers/mmc/cv1800b_sdhci.c
index b756649f90f3..5c129682daba 100644
--- a/drivers/mmc/cv1800b_sdhci.c
+++ b/drivers/mmc/cv1800b_sdhci.c
@@ -8,11 +8,17 @@
#include <sdhci.h>
#include <linux/delay.h>
+#define CV18XX_SDHCI_MSHC_CTRL 0x200
+#define CV18XX_SDHCI_PHY_CONFIG 0x24c
#define SDHCI_PHY_TX_RX_DLY 0x240
#define MMC_MAX_CLOCK 375000000
#define TUNE_MAX_PHCODE 128
#define PHY_TX_SRC_INVERT BIT(8)
+#define PHY_RX_SRC_INVERT BIT(24)
+
+#define CV18XX_LATANCY_1T BIT(1)
+#define CV18XX_PHY_TX_BPS BIT(0)
struct cv1800b_sdhci_plat {
struct mmc_config cfg;
@@ -64,10 +70,29 @@ static int cv1800b_execute_tuning(struct mmc *mmc, u8
opcode)
}
#endif
+static int cv1800b_deferred_probe(struct sdhci_host *host)
+{
+ u32 val;
+
+ val = sdhci_readl(host, CV18XX_SDHCI_MSHC_CTRL);
+ val |= CV18XX_LATANCY_1T;
+ sdhci_writel(host, val, CV18XX_SDHCI_MSHC_CTRL);
+
+ val = sdhci_readl(host, CV18XX_SDHCI_PHY_CONFIG);
+ val |= CV18XX_PHY_TX_BPS;
+ sdhci_writel(host, val, CV18XX_SDHCI_PHY_CONFIG);
+
+ val = PHY_TX_SRC_INVERT | PHY_RX_SRC_INVERT;
+ sdhci_writel(host, val, SDHCI_PHY_TX_RX_DLY);
+
+ return 0;
+}
+
const struct sdhci_ops cv1800b_sdhci_sd_ops = {
#if CONFIG_IS_ENABLED(MMC_SUPPORTS_TUNING)
.platform_execute_tuning = cv1800b_execute_tuning,
#endif
+ .deferred_probe = cv1800b_deferred_probe,
};
static int cv1800b_sdhci_bind(struct udevice *dev)
--
2.55.0
--
Best regards,
Andrei Lalaev
