ARM: EXYNOS: Create virtual I/O mapping for Chip-ID controller using device tree

On device tree enabled exynos platforms, retrieve the physical base address
of the chip-id controller from device tree and create a virtual I/O mapping
for the chip-id controller. This helps to remove the chip-id controller entry
from the statically defined I/O mapping tables.

Signed-off-by: Thomas Abraham <thomas.abraham@linaro.org>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>

2 files changed, 30 insertions, 24 deletions

diff --git a/arch/arm/mach-exynos/common.c b/arch/arm/mach-exynos/common.c
index 02e35abd136b..e720352f85cb 100644
--- a/arch/arm/mach-exynos/common.c
+++ b/arch/arm/mach-exynos/common.c
@@ -119,17 +119,6 @@ static struct map_desc exynos_iodesc[] __initdata = {
         },
 };
 
-#ifdef CONFIG_ARCH_EXYNOS5
-static struct map_desc exynos5440_iodesc[] __initdata = {
-        {
-                .virtual        = (unsigned long)S5P_VA_CHIPID,
-                .pfn            = __phys_to_pfn(EXYNOS5440_PA_CHIPID),
-                .length         = SZ_4K,
-                .type           = MT_DEVICE,
-        },
-};
-#endif
-
 static struct map_desc exynos4_iodesc[] __initdata = {
         {
                 .virtual        = (unsigned long)S3C_VA_SYS,
@@ -320,6 +309,31 @@ void __init exynos_init_late(void)
         exynos_pm_late_initcall();
 }
 
+#ifdef CONFIG_OF
+int __init exynos_fdt_map_chipid(unsigned long node, const char *uname,
+                                        int depth, void *data)
+{
+        struct map_desc iodesc;
+        __be32 *reg;
+        unsigned long len;
+
+        if (!of_flat_dt_is_compatible(node, "samsung,exynos4210-chipid") &&
+                !of_flat_dt_is_compatible(node, "samsung,exynos5440-clock"))
+                return 0;
+
+        reg = of_get_flat_dt_prop(node, "reg", &len);
+        if (reg == NULL || len != (sizeof(unsigned long) * 2))
+                return 0;
+
+        iodesc.pfn = __phys_to_pfn(be32_to_cpu(reg[0]));
+        iodesc.length = be32_to_cpu(reg[1]) - 1;
+        iodesc.virtual = (unsigned long)S5P_VA_CHIPID;
+        iodesc.type = MT_DEVICE;
+        iotable_init(&iodesc, 1);
+        return 1;
+}
+#endif
+
 /*
  * exynos_map_io
  *
@@ -328,19 +342,12 @@ void __init exynos_init_late(void)
 
 void __init exynos_init_io(struct map_desc *mach_desc, int size)
 {
-        struct map_desc *iodesc = exynos_iodesc;
-        int iodesc_sz = ARRAY_SIZE(exynos_iodesc);
-#if defined(CONFIG_OF) && defined(CONFIG_ARCH_EXYNOS5)
-        unsigned long root = of_get_flat_dt_root();
-
-        /* initialize the io descriptors we need for initialization */
-        if (of_flat_dt_is_compatible(root, "samsung,exynos5440")) {
-                iodesc = exynos5440_iodesc;
-                iodesc_sz = ARRAY_SIZE(exynos5440_iodesc);
-        }
+#ifdef CONFIG_OF
+        if (initial_boot_params)
+                of_scan_flat_dt(exynos_fdt_map_chipid, NULL);
+        else
 #endif
-
-        iotable_init(iodesc, iodesc_sz);
+                iotable_init(exynos_iodesc, ARRAY_SIZE(exynos_iodesc));
 
         if (mach_desc)
                 iotable_init(mach_desc, size);
diff --git a/arch/arm/mach-exynos/include/mach/map.h b/arch/arm/mach-exynos/include/mach/map.h
index 7f99b7b187d6..be7abc7ceb67 100644
--- a/arch/arm/mach-exynos/include/mach/map.h
+++ b/arch/arm/mach-exynos/include/mach/map.h
@@ -53,7 +53,6 @@
 #define EXYNOS4_PA_ONENAND_DMA          0x0C600000
 
 #define EXYNOS_PA_CHIPID                0x10000000
-#define EXYNOS5440_PA_CHIPID            0x00160000
 
 #define EXYNOS4_PA_SYSCON               0x10010000
 #define EXYNOS5_PA_SYSCON               0x10050100