If the "Page Mode" is not enabled on the device,
read operations from PSRAM may result in incorrect data.
Signed-off-by: Alexey Brodkin <abrodkin@xxxxxxxxxxxx>
---
board/synopsys/emsdp/emsdp.c | 37 +++++++++++++++++++++++++++++++++++++
configs/emsdp_defconfig | 1 +
2 files changed, 38 insertions(+)
diff --git a/board/synopsys/emsdp/emsdp.c b/board/synopsys/emsdp/emsdp.c
index c0770b58c1..3bf4a1879b 100644
--- a/board/synopsys/emsdp/emsdp.c
+++ b/board/synopsys/emsdp/emsdp.c
@@ -48,6 +48,43 @@ int mach_cpu_init(void)
return 0;
}
+int board_early_init_r(void)
+{
+#define EMSDP_PSRAM_BASE 0xf2001000
+#define PSRAM_FLASH_CONFIG_REG_0 (void *)(EMSDP_PSRAM_BASE + 0x10)
+#define PSRAM_FLASH_CONFIG_REG_1 (void *)(EMSDP_PSRAM_BASE + 0x14)
+#define CRE_ENABLE BIT(31)
+#define CRE_DRIVE_CMD BIT(6)
+
+#define PSRAM_RCR_DPD BIT(4)
+#define PSRAM_RCR_PAGE_MODE BIT(7)
+
+/*
+ * PSRAM_FLASH_CONFIG_REG_x[30:15] to the address lines[16:1] of flash,
+ * thus "<< 1".
+ */
+#define PSRAM_RCR_SETUP ((PSRAM_RCR_DPD | PSRAM_RCR_PAGE_MODE) << 1)
+
+ // Switch PSRAM controller to command mode
+ writel(CRE_ENABLE | CRE_DRIVE_CMD, PSRAM_FLASH_CONFIG_REG_0);
+ // Program Refresh Configuration Register (RCR) for BANK0
+ writew(0, (void *)(0x10000000 + PSRAM_RCR_SETUP));
+ // Switch PSRAM controller back to memory mode
+ writel(0, PSRAM_FLASH_CONFIG_REG_0);
+
+
+ // Switch PSRAM controller to command mode
+ writel(CRE_ENABLE | CRE_DRIVE_CMD, PSRAM_FLASH_CONFIG_REG_1);
+ // Program Refresh Configuration Register (RCR) for BANK1
+ writew(0, (void *)(0x10800000 + PSRAM_RCR_SETUP));
+ // Switch PSRAM controller back to memory mode
+ writel(0, PSRAM_FLASH_CONFIG_REG_1);
+
+ printf("PSRAM initialized.\n");
+
+ return 0;
+}
+
int board_mmc_init(bd_t *bis)
{
struct dwmci_host *host = NULL;
diff --git a/configs/emsdp_defconfig b/configs/emsdp_defconfig
index 64281d0529..5e55e3e2b2 100644
--- a/configs/emsdp_defconfig
+++ b/configs/emsdp_defconfig
@@ -7,6 +7,7 @@ CONFIG_ENV_SIZE=0x1000
CONFIG_SYS_CLK_FREQ=40000000
# CONFIG_ARCH_FIXUP_FDT_MEMORY is not set
CONFIG_VERSION_VARIABLE=y
+CONFIG_BOARD_EARLY_INIT_R=y
CONFIG_HUSH_PARSER=y
CONFIG_SYS_PROMPT="emsdp# "
# CONFIG_CMD_BOOTD is not set
--
2.16.2
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