ARMV7: OMAP4: Calculate SDRAM size

Calculate the SDRAM size from DMM configuration registers instead of using
hard-coded values. This gives correct values for all different boards.

It's assumed that DMM sections do not overlap memory areas.

Signed-off-by: Aneesh V <aneesh@ti.com>
Tested-by: Steve Sakoman <steve@sakoman.com>
Signed-off-by: Sandeep Paulraj <s-paulraj@ti.com>

diff --git a/arch/arm/cpu/armv7/omap4/board.c b/arch/arm/cpu/armv7/omap4/board.c
index 195be6eea134234f7d2e7ce93941581cda070e35..8c1f3953edd49153e6048f123d8e65db0310b9ab 100644 (file)
--- a/arch/arm/cpu/armv7/omap4/board.c
+++ b/arch/arm/cpu/armv7/omap4/board.c
@@ -30,6 +30,7 @@
 #include <common.h>
 #include <asm/arch/cpu.h>
 #include <asm/arch/sys_proto.h>
+#include <asm/sizes.h>
 
 /*
  * Routine: s_init
@@ -66,6 +67,33 @@ void watchdog_init(void)
        writel(WD_UNLOCK2, &wd2_base->wspr);
 }
 
+
+/*
+ * This function finds the SDRAM size available in the system
+ * based on DMM section configurations
+ * This is needed because the size of memory installed may be
+ * different on different versions of the board
+ */
+u32 sdram_size(void)
+{
+       u32 section, i, total_size = 0, size, addr;
+       for (i = 0; i < 4; i++) {
+               section = __raw_readl(DMM_LISA_MAP_BASE + i*4);
+               addr = section & DMM_LISA_MAP_SYS_ADDR_MASK;
+               /* See if the address is valid */
+               if ((addr >= OMAP44XX_DRAM_ADDR_SPACE_START) &&
+                   (addr < OMAP44XX_DRAM_ADDR_SPACE_END)) {
+                       size    = ((section & DMM_LISA_MAP_SYS_SIZE_MASK) >>
+                                   DMM_LISA_MAP_SYS_SIZE_SHIFT);
+                       size    = 1 << size;
+                       size    *= SZ_16M;
+                       total_size += size;
+               }
+       }
+       return total_size;
+}
+
+
 /*
  * Routine: dram_init
  * Description: sets uboots idea of sdram size
@@ -75,7 +103,7 @@ int dram_init(void)
        DECLARE_GLOBAL_DATA_PTR;
 
        gd->bd->bi_dram[0].start = 0x80000000;
-       gd->bd->bi_dram[0].size = 512 << 20;
+       gd->bd->bi_dram[0].size = sdram_size();
        return 0;
 }
 

diff --git a/arch/arm/include/asm/arch-omap4/omap4.h b/arch/arm/include/asm/arch-omap4/omap4.h
index d0c808d1217cbbbf190adb48bd7eccf5df57a324..a30bb332e8be83988d7fd0c8978e970f54f355e7 100644 (file)
--- a/arch/arm/include/asm/arch-omap4/omap4.h
+++ b/arch/arm/include/asm/arch-omap4/omap4.h
@@ -42,6 +42,10 @@
 #define OMAP44XX_L4_WKUP_BASE  0x4A300000
 #define OMAP44XX_L4_PER_BASE   0x48000000
 
+#define OMAP44XX_DRAM_ADDR_SPACE_START 0x80000000
+#define OMAP44XX_DRAM_ADDR_SPACE_END   0xD0000000
+
+
 /* CONTROL */
 #define CTRL_BASE              (OMAP44XX_L4_CORE_BASE + 0x2000)
 #define CONTROL_PADCONF_CORE   (OMAP44XX_L4_CORE_BASE + 0x100000)
@@ -66,6 +70,12 @@
 /* GPMC */
 #define OMAP44XX_GPMC_BASE     0x50000000
 
+/* DMM */
+#define OMAP44XX_DMM_BASE              0x4E000000
+#define DMM_LISA_MAP_BASE              (OMAP44XX_DMM_BASE + 0x40)
+#define DMM_LISA_MAP_SYS_SIZE_MASK     (7 << 20)
+#define DMM_LISA_MAP_SYS_SIZE_SHIFT    20
+#define DMM_LISA_MAP_SYS_ADDR_MASK     (0xFF << 24)
 /*
  * Hardware Register Details
  */