csky: pgtable.h: Coding convention

C-SKY page table attributes only have 'Dirty' and 'Valid' to
emulate 'PRESENT, READ, WRITE, EXEC, DIRTY, ACCESSED'.

This patch cleanup unnecessary definition.
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Cc: Arnd Bergmann <arnd@arndb.de>

arch/csky/abiv1/inc/abi/pgtable-bits.h

@@ -5,33 +5,24 @@
 #define __ASM_CSKY_PGTABLE_BITS_H
 
 /* implemented in software */
-#define _PAGE_ACCESSED		(1<<3)
-#define PAGE_ACCESSED_BIT	(3)
-
+#define _PAGE_PRESENT		(1<<0)
 #define _PAGE_READ		(1<<1)
 #define _PAGE_WRITE		(1<<2)
-#define _PAGE_PRESENT		(1<<0)
-
+#define _PAGE_ACCESSED		(1<<3)
 #define _PAGE_MODIFIED		(1<<4)
-#define PAGE_MODIFIED_BIT	(4)
 
 /* implemented in hardware */
 #define _PAGE_GLOBAL		(1<<6)
-
 #define _PAGE_VALID		(1<<7)
-#define PAGE_VALID_BIT		(7)
-
 #define _PAGE_DIRTY		(1<<8)
-#define PAGE_DIRTY_BIT		(8)
 
 #define _PAGE_CACHE		(3<<9)
 #define _PAGE_UNCACHE		(2<<9)
 #define _PAGE_SO		_PAGE_UNCACHE
-
 #define _CACHE_MASK		(7<<9)
 
-#define _CACHE_CACHED		(_PAGE_VALID | _PAGE_CACHE)
-#define _CACHE_UNCACHED		(_PAGE_VALID | _PAGE_UNCACHE)
+#define _CACHE_CACHED		_PAGE_CACHE
+#define _CACHE_UNCACHED		_PAGE_UNCACHE
 
 #define HAVE_ARCH_UNMAPPED_AREA
 

arch/csky/abiv2/inc/abi/pgtable-bits.h

@@ -6,32 +6,22 @@
 
 /* implemented in software */
 #define _PAGE_ACCESSED		(1<<7)
-#define PAGE_ACCESSED_BIT	(7)
-
 #define _PAGE_READ		(1<<8)
 #define _PAGE_WRITE		(1<<9)
 #define _PAGE_PRESENT		(1<<10)
-
 #define _PAGE_MODIFIED		(1<<11)
-#define PAGE_MODIFIED_BIT	(11)
 
 /* implemented in hardware */
 #define _PAGE_GLOBAL		(1<<0)
-
 #define _PAGE_VALID		(1<<1)
-#define PAGE_VALID_BIT		(1)
-
 #define _PAGE_DIRTY		(1<<2)
-#define PAGE_DIRTY_BIT		(2)
 
 #define _PAGE_SO		(1<<5)
 #define _PAGE_BUF		(1<<6)
-
 #define _PAGE_CACHE		(1<<3)
-
 #define _CACHE_MASK		_PAGE_CACHE
 
-#define _CACHE_CACHED		(_PAGE_VALID | _PAGE_CACHE | _PAGE_BUF)
-#define _CACHE_UNCACHED		(_PAGE_VALID)
+#define _CACHE_CACHED		(_PAGE_CACHE | _PAGE_BUF)
+#define _CACHE_UNCACHED		(0)
 
 #endif /* __ASM_CSKY_PGTABLE_BITS_H */

arch/csky/include/asm/pgtable.h

@@ -41,9 +41,6 @@
 #define pfn_pte(pfn, prot) __pte(((unsigned long long)(pfn) << PAGE_SHIFT) \
 				| pgprot_val(prot))
 
-#define __READABLE	(_PAGE_READ | _PAGE_VALID | _PAGE_ACCESSED)
-#define __WRITEABLE	(_PAGE_WRITE | _PAGE_DIRTY | _PAGE_MODIFIED)
-
 #define _PAGE_CHG_MASK	(PAGE_MASK | _PAGE_ACCESSED | _PAGE_MODIFIED | \
 			 _CACHE_MASK)
 
@@ -59,43 +56,46 @@
 					pgprot_val(pgprot))
 
 /*
- * CSKY can't do page protection for execute, and considers that the same like
- * read. Also, write permissions imply read permissions. This is the closest
- * we can get by reasonable means..
+ * C-SKY only has VALID and DIRTY bit in hardware. So we need to use the
+ * two bits emulate PRESENT, READ, WRITE, EXEC, MODIFIED, ACCESSED.
  */
 #define _PAGE_BASE	(_PAGE_PRESENT | _PAGE_ACCESSED)
 
-#define PAGE_NONE	__pgprot(_PAGE_BASE | _CACHE_CACHED)
-#define PAGE_SHARED	__pgprot(_PAGE_BASE | _PAGE_READ | _PAGE_WRITE | \
+#define PAGE_NONE	__pgprot(_PAGE_BASE | \
+				_CACHE_CACHED)
+#define PAGE_READ	__pgprot(_PAGE_BASE | _PAGE_READ | \
 				_CACHE_CACHED)
-#define PAGE_COPY	__pgprot(_PAGE_BASE | _PAGE_READ | _CACHE_CACHED)
-#define PAGE_READONLY	__pgprot(_PAGE_BASE | _PAGE_READ | _CACHE_CACHED)
-#define PAGE_KERNEL	__pgprot(_PAGE_BASE | __READABLE | __WRITEABLE | \
-				_PAGE_GLOBAL | _CACHE_CACHED)
-#define PAGE_USERIO	__pgprot(_PAGE_BASE | _PAGE_READ | _PAGE_WRITE | \
+#define PAGE_WRITE	__pgprot(_PAGE_BASE | _PAGE_READ | _PAGE_WRITE | \
+				_CACHE_CACHED)
+#define PAGE_SHARED PAGE_WRITE
+
+#define PAGE_KERNEL	__pgprot(_PAGE_BASE | _PAGE_READ | _PAGE_VALID | \
+				_PAGE_WRITE | _PAGE_DIRTY | _PAGE_MODIFIED | \
+				_PAGE_GLOBAL | \
 				_CACHE_CACHED)
 
-#define _PAGE_IOREMAP \
-	(_PAGE_BASE | __READABLE | __WRITEABLE | _PAGE_GLOBAL | \
-	 _CACHE_UNCACHED | _PAGE_SO)
+#define _PAGE_IOREMAP		(_PAGE_BASE | _PAGE_READ | _PAGE_VALID | \
+				_PAGE_WRITE | _PAGE_DIRTY | _PAGE_MODIFIED | \
+				_PAGE_GLOBAL | \
+				_CACHE_UNCACHED | _PAGE_SO)
 
 #define __P000	PAGE_NONE
-#define __P001	PAGE_READONLY
-#define __P010	PAGE_COPY
-#define __P011	PAGE_COPY
-#define __P100	PAGE_READONLY
-#define __P101	PAGE_READONLY
-#define __P110	PAGE_COPY
-#define __P111	PAGE_COPY
+#define __P001	PAGE_READ
+#define __P010	PAGE_READ
+#define __P011	PAGE_READ
+#define __P100	PAGE_READ
+#define __P101	PAGE_READ
+#define __P110	PAGE_READ
+#define __P111	PAGE_READ
 
 #define __S000	PAGE_NONE
-#define __S001	PAGE_READONLY
-#define __S010	PAGE_SHARED
-#define __S011	PAGE_SHARED
-#define __S100	PAGE_READONLY
-#define __S101	PAGE_READONLY
-#define __S110	PAGE_SHARED
-#define __S111	PAGE_SHARED
+#define __S001	PAGE_READ
+#define __S010	PAGE_WRITE
+#define __S011	PAGE_WRITE
+#define __S100	PAGE_READ
+#define __S101	PAGE_READ
+#define __S110	PAGE_WRITE
+#define __S111	PAGE_WRITE
 
 extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
 #define ZERO_PAGE(vaddr)	(virt_to_page(empty_zero_page))