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authorFranck Bui-Huu <fbuihuu@gmail.com>2007-01-10 09:44:05 +0100
committerRalf Baechle <ralf@linux-mips.org>2007-02-06 16:53:13 +0000
commit6f284a2ce7b8bc49cb8455b1763357897a899abb (patch)
treeabf59702fad617780f59594aa8939db7ec4c76d6 /include/asm-mips
parentdb84dc61552ae0d198a8133d28b80c3838930ba8 (diff)
[MIPS] FLATMEM: introduce PHYS_OFFSET.
The old code was assuming that min_low_pfn was always 0. This means that platforms having a big hole at their memory start paid the price of wasting some memory for the allocation of unused entries in mem_map[]. This patch prevents this waste. It introduces PHYS_OFFSET define which is the start of the physical memory and uses it wherever needed. Specially when converting physical/virtual addresses into virtual/physical ones. Currently all platforms defines PHYS_OFFSET to 0. Signed-off-by: Franck Bui-Huu <fbuihuu@gmail.com> Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'include/asm-mips')
-rw-r--r--include/asm-mips/io.h4
-rw-r--r--include/asm-mips/page.h25
2 files changed, 23 insertions, 6 deletions
diff --git a/include/asm-mips/io.h b/include/asm-mips/io.h
index d77b657c09c..67f08107890 100644
--- a/include/asm-mips/io.h
+++ b/include/asm-mips/io.h
@@ -115,7 +115,7 @@ static inline void set_io_port_base(unsigned long base)
*/
static inline unsigned long virt_to_phys(volatile const void *address)
{
- return (unsigned long)address - PAGE_OFFSET;
+ return (unsigned long)address - PAGE_OFFSET + PHYS_OFFSET;
}
/*
@@ -132,7 +132,7 @@ static inline unsigned long virt_to_phys(volatile const void *address)
*/
static inline void * phys_to_virt(unsigned long address)
{
- return (void *)(address + PAGE_OFFSET);
+ return (void *)(address + PAGE_OFFSET - PHYS_OFFSET);
}
/*
diff --git a/include/asm-mips/page.h b/include/asm-mips/page.h
index 2f9e1a9ec51..d3fbd83ff54 100644
--- a/include/asm-mips/page.h
+++ b/include/asm-mips/page.h
@@ -34,6 +34,20 @@
#ifndef __ASSEMBLY__
+/*
+ * This gives the physical RAM offset.
+ */
+#ifndef PHYS_OFFSET
+#define PHYS_OFFSET 0UL
+#endif
+
+/*
+ * It's normally defined only for FLATMEM config but it's
+ * used in our early mem init code for all memory models.
+ * So always define it.
+ */
+#define ARCH_PFN_OFFSET PFN_UP(PHYS_OFFSET)
+
#include <linux/pfn.h>
#include <asm/io.h>
@@ -132,20 +146,23 @@ typedef struct { unsigned long pgprot; } pgprot_t;
/* to align the pointer to the (next) page boundary */
#define PAGE_ALIGN(addr) (((addr) + PAGE_SIZE - 1) & PAGE_MASK)
+/*
+ * __pa()/__va() should be used only during mem init.
+ */
#if defined(CONFIG_64BIT) && !defined(CONFIG_BUILD_ELF64)
#define __pa_page_offset(x) ((unsigned long)(x) < CKSEG0 ? PAGE_OFFSET : CKSEG0)
#else
#define __pa_page_offset(x) PAGE_OFFSET
#endif
-#define __pa(x) ((unsigned long)(x) - __pa_page_offset(x))
-#define __pa_symbol(x) __pa(RELOC_HIDE((unsigned long)(x),0))
-#define __va(x) ((void *)((unsigned long)(x) + PAGE_OFFSET))
+#define __pa(x) ((unsigned long)(x) - __pa_page_offset(x) + 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 pfn_to_kaddr(pfn) __va((pfn) << PAGE_SHIFT)
#ifdef CONFIG_FLATMEM
-#define pfn_valid(pfn) ((pfn) < max_mapnr)
+#define pfn_valid(pfn) ((pfn) >= ARCH_PFN_OFFSET && (pfn) < max_mapnr)
#elif defined(CONFIG_SPARSEMEM)