ram: rk3399: debug: Add sdram_print_stride

Add code to print the channel stride, this would help to
print the stride of associated channel.

Here is sample print on LPDDR4, 50MHz.
256B stride

Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
Signed-off-by: YouMin Chen <cym@rock-chips.com>
Reviewed-by: Kever Yang <Kever.yang@rock-chips.com>
diff --git a/arch/arm/include/asm/arch-rockchip/sdram_common.h b/arch/arm/include/asm/arch-rockchip/sdram_common.h
index cfbb511..b7549f5 100644
--- a/arch/arm/include/asm/arch-rockchip/sdram_common.h
+++ b/arch/arm/include/asm/arch-rockchip/sdram_common.h
@@ -102,10 +102,15 @@
 				 struct sdram_base_params *base)
 {
 }
+
+inline void sdram_print_stride(unsigned int stride)
+{
+}
 #else
 void sdram_print_dram_type(unsigned char dramtype);
 void sdram_print_ddr_info(struct sdram_cap_info *cap_info,
 			  struct sdram_base_params *base);
+void sdram_print_stride(unsigned int stride);
 #endif /* CONFIG_RAM_ROCKCHIP_DEBUG */
 
 #endif
diff --git a/drivers/ram/rockchip/sdram_debug.c b/drivers/ram/rockchip/sdram_debug.c
index 19e9225..9cf6626 100644
--- a/drivers/ram/rockchip/sdram_debug.c
+++ b/drivers/ram/rockchip/sdram_debug.c
@@ -116,3 +116,32 @@
 	printdec(cap >> 20);
 	printascii("MB\n");
 }
+
+void sdram_print_stride(unsigned int stride)
+{
+	switch (stride) {
+	case 0xc:
+		printf("128B stride\n");
+		break;
+	case 5:
+	case 9:
+	case 0xd:
+	case 0x11:
+	case 0x19:
+		printf("256B stride\n");
+		break;
+	case 0xa:
+	case 0xe:
+	case 0x12:
+		printf("512B stride\n");
+		break;
+	case 0xf:
+		printf("4K stride\n");
+		break;
+	case 0x1f:
+		printf("32MB + 256B stride\n");
+		break;
+	default:
+		printf("no stride\n");
+	}
+}