sh: Free up some and document PTEL flags. (ef48e8e3) · Commits · 戴 / test

include/asm-sh/pgtable.h

+45 −31

Original line number	Diff line number	Diff line
		@@ -54,8 +54,31 @@ extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
		#define VMALLOC_START (P3SEG+0x00100000)
		#define VMALLOC_END (FIXADDR_START-2*PAGE_SIZE)

		/*
		* Linux PTEL encoding.
		*
		* Hardware and software bit definitions for the PTEL value:
		*
		* - Bits 0 and 7 are reserved on SH-3 (_PAGE_WT and _PAGE_SZ1 on SH-4).
		*
		* - Bit 1 is the SH-bit, but is unused on SH-3 due to an MMU bug (the
		* hardware PTEL value can't have the SH-bit set when MMUCR.IX is set,
		* which is the default in cpu-sh3/mmu_context.h:MMU_CONTROL_INIT).
		*
		* In order to keep this relatively clean, do not use these for defining
		* SH-3 specific flags until all of the other unused bits have been
		* exhausted.
		*
		* - Bit 9 is reserved by everyone and used by _PAGE_PROTNONE.
		*
		* - Bits 10 and 11 are low bits of the PPN that are reserved on >= 4K pages.
		* Bit 10 is used for _PAGE_ACCESSED, bit 11 remains unused.
		*
		* - Bits 31, 30, and 29 remain unused by everyone and can be used for future
		* software flags, although care must be taken to update _PAGE_CLEAR_FLAGS.
		*/
		#define _PAGE_WT 0x001 /* WT-bit on SH-4, 0 on SH-3 */
		#define _PAGE_HW_SHARED 0x002 /* SH-bit : page is shared among processes */
		#define _PAGE_HW_SHARED 0x002 /* SH-bit : shared among processes */
		#define _PAGE_DIRTY 0x004 /* D-bit : page changed */
		#define _PAGE_CACHABLE 0x008 /* C-bit : cachable */
		#define _PAGE_SZ0 0x010 /* SZ0-bit : Size of page */
		@@ -65,8 +88,6 @@ extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
		#define _PAGE_PRESENT 0x100 /* V-bit : page is valid */
		#define _PAGE_PROTNONE 0x200 /* software: if not present */
		#define _PAGE_ACCESSED 0x400 /* software: page referenced */
		#define _PAGE_U0_SHARED 0x800 /* software: page is shared in user space */

		#define _PAGE_FILE _PAGE_WT /* software: pagecache or swap? */

		/* software: moves to PTEA.TC (Timing Control) */
		@@ -82,22 +103,17 @@ extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
		#define _PAGE_PCC_ATR8 0x60000000 /* Attribute Memory space, 8 bit bus */
		#define _PAGE_PCC_ATR16 0x60000001 /* Attribute Memory space, 6 bit bus */

		/* Mask which drop software flags
		* We also drop WT bit since it is used for _PAGE_FILE
		* bit in this implementation.
		*/
		#define _PAGE_CLEAR_FLAGS (_PAGE_WT \| _PAGE_PROTNONE \| _PAGE_ACCESSED \| _PAGE_U0_SHARED)

		#if defined(CONFIG_CPU_SH3)
		/*
		* MMU on SH-3 has bug on SH-bit: We can't use it if MMUCR.IX=1.
		* Work around: Just drop SH-bit.
		*/
		#define _PAGE_FLAGS_HARDWARE_MASK (0x1fffffff & ~(_PAGE_CLEAR_FLAGS \| _PAGE_HW_SHARED))
		/* Mask which drops unused bits from the PTEL value */
		#ifdef CONFIG_CPU_SH3
		#define _PAGE_CLEAR_FLAGS (_PAGE_PROTNONE \| _PAGE_ACCESSED\| \
		_PAGE_FILE \| _PAGE_SZ1 \| \
		_PAGE_HW_SHARED)
		#else
		#define _PAGE_FLAGS_HARDWARE_MASK (0x1fffffff & ~(_PAGE_CLEAR_FLAGS))
		#define _PAGE_CLEAR_FLAGS (_PAGE_PROTNONE \| _PAGE_ACCESSED \| _PAGE_FILE)
		#endif

		#define _PAGE_FLAGS_HARDWARE_MASK (0x1fffffff & ~(_PAGE_CLEAR_FLAGS))

		/* Hardware flags: SZ0=1 (4k-byte) */
		#define _PAGE_FLAGS_HARD _PAGE_SZ0

		@@ -107,17 +123,15 @@ extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
		#define _PAGE_SZHUGE (_PAGE_SZ0 \| _PAGE_SZ1)
		#endif

		#define _PAGE_SHARED _PAGE_U0_SHARED

		#define _PAGE_TABLE (_PAGE_PRESENT \| _PAGE_RW \| _PAGE_USER \| _PAGE_ACCESSED \| _PAGE_DIRTY)
		#define _KERNPG_TABLE (_PAGE_PRESENT \| _PAGE_RW \| _PAGE_ACCESSED \| _PAGE_DIRTY)
		#define _PAGE_CHG_MASK (PTE_MASK \| _PAGE_ACCESSED \| _PAGE_CACHABLE \| _PAGE_DIRTY \| _PAGE_SHARED)
		#define _PAGE_CHG_MASK (PTE_MASK \| _PAGE_ACCESSED \| _PAGE_CACHABLE \| _PAGE_DIRTY)

		#ifndef __ASSEMBLY__

		#ifdef CONFIG_MMU
		#define PAGE_NONE __pgprot(_PAGE_PROTNONE \| _PAGE_CACHABLE \|_PAGE_ACCESSED \| _PAGE_FLAGS_HARD)
		#define PAGE_SHARED __pgprot(_PAGE_PRESENT \| _PAGE_RW \| _PAGE_USER \| _PAGE_CACHABLE \|_PAGE_ACCESSED \| _PAGE_SHARED \| _PAGE_FLAGS_HARD)
		#define PAGE_SHARED __pgprot(_PAGE_PRESENT \| _PAGE_RW \| _PAGE_USER \| _PAGE_CACHABLE \|_PAGE_ACCESSED \| _PAGE_FLAGS_HARD)
		#define PAGE_COPY __pgprot(_PAGE_PRESENT \| _PAGE_USER \| _PAGE_CACHABLE \| _PAGE_ACCESSED \| _PAGE_FLAGS_HARD)
		#define PAGE_READONLY __pgprot(_PAGE_PRESENT \| _PAGE_USER \| _PAGE_CACHABLE \| _PAGE_ACCESSED \| _PAGE_FLAGS_HARD)
		#define PAGE_KERNEL __pgprot(_PAGE_PRESENT \| _PAGE_RW \| _PAGE_CACHABLE \| _PAGE_DIRTY \| _PAGE_ACCESSED \| _PAGE_HW_SHARED \| _PAGE_FLAGS_HARD)

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