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Diffstat (limited to 'arch/csky/include/asm/page.h')
-rw-r--r--arch/csky/include/asm/page.h39
1 files changed, 16 insertions, 23 deletions
diff --git a/arch/csky/include/asm/page.h b/arch/csky/include/asm/page.h
index 73cf2bd66a13..9738eacefdc7 100644
--- a/arch/csky/include/asm/page.h
+++ b/arch/csky/include/asm/page.h
@@ -8,7 +8,7 @@
#include <linux/const.h>
/*
- * PAGE_SHIFT determines the page size
+ * PAGE_SHIFT determines the page size: 4KB
*/
#define PAGE_SHIFT 12
#define PAGE_SIZE (_AC(1, UL) << PAGE_SHIFT)
@@ -17,12 +17,18 @@
#define THREAD_MASK (~(THREAD_SIZE - 1))
#define THREAD_SHIFT (PAGE_SHIFT + 1)
+
/*
- * NOTE: virtual isn't really correct, actually it should be the offset into the
- * memory node, but we have no highmem, so that works for now.
- * TODO: implement (fast) pfn<->pgdat_idx conversion functions, this makes lots
- * of the shifts unnecessary.
+ * For C-SKY "User-space:Kernel-space" is "2GB:2GB" fixed by hardware and there
+ * are two segment registers (MSA0 + MSA1) to mapping 512MB + 512MB physical
+ * address region. We use them mapping kernel 1GB direct-map address area and
+ * for more than 1GB of memory we use highmem.
*/
+#define PAGE_OFFSET 0x80000000
+#define SSEG_SIZE 0x20000000
+#define LOWMEM_LIMIT (SSEG_SIZE * 2)
+
+#define PHYS_OFFSET_OFFSET (CONFIG_RAM_BASE & (SSEG_SIZE - 1))
#ifndef __ASSEMBLY__
@@ -50,9 +56,6 @@ struct page;
struct vm_area_struct;
-/*
- * These are used to make use of C type-checking..
- */
typedef struct { unsigned long pte_low; } pte_t;
#define pte_val(x) ((x).pte_low)
@@ -69,18 +72,13 @@ typedef struct page *pgtable_t;
#define __pgd(x) ((pgd_t) { (x) })
#define __pgprot(x) ((pgprot_t) { (x) })
-#endif /* !__ASSEMBLY__ */
+extern unsigned long va_pa_offset;
-#define PHYS_OFFSET (CONFIG_RAM_BASE & ~(LOWMEM_LIMIT - 1))
-#define PHYS_OFFSET_OFFSET (CONFIG_RAM_BASE & (LOWMEM_LIMIT - 1))
-#define ARCH_PFN_OFFSET PFN_DOWN(CONFIG_RAM_BASE)
+#define ARCH_PFN_OFFSET PFN_DOWN(va_pa_offset + PHYS_OFFSET_OFFSET)
-#define PAGE_OFFSET 0x80000000
-#define LOWMEM_LIMIT 0x40000000
+#define __pa(x) ((unsigned long)(x) - PAGE_OFFSET + va_pa_offset)
+#define __va(x) ((void *)((unsigned long)(x) + PAGE_OFFSET - va_pa_offset))
-#define __pa(x) ((unsigned long)(x) - PAGE_OFFSET + PHYS_OFFSET)
-#define __va(x) ((void *)((unsigned long)(x) + PAGE_OFFSET - \
- PHYS_OFFSET))
#define __pa_symbol(x) __pa(RELOC_HIDE((unsigned long)(x), 0))
#define MAP_NR(x) PFN_DOWN((unsigned long)(x) - PAGE_OFFSET - \
@@ -90,15 +88,10 @@ typedef struct page *pgtable_t;
#define VM_DATA_DEFAULT_FLAGS (VM_READ | VM_WRITE | VM_EXEC | \
VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
-/*
- * main RAM and kernel working space are coincident at 0x80000000, but to make
- * life more interesting, there's also an uncached virtual shadow at 0xb0000000
- * - these mappings are fixed in the MMU
- */
-
#define pfn_to_kaddr(x) __va(PFN_PHYS(x))
#include <asm-generic/memory_model.h>
#include <asm-generic/getorder.h>
+#endif /* !__ASSEMBLY__ */
#endif /* __ASM_CSKY_PAGE_H */