arch/arm/mm/cache-v4wb.S - linux - Git at Google

 /* SPDX-License-Identifier: GPL-2.0-only */
 /*
  *  linux/arch/arm/mm/cache-v4wb.S
  *
  *  Copyright (C) 1997-2002 Russell king
  */
 #include <linux/linkage.h>
 #include <linux/init.h>
 #include <asm/assembler.h>
 #include <asm/memory.h>
 #include <asm/page.h>
 #include "proc-macros.S"

 /*
  * The size of one data cache line.
  */
 #define CACHE_DLINESIZE	32

 /*
  * The total size of the data cache.
  */
 #if defined(CONFIG_CPU_SA110)
 # define CACHE_DSIZE	16384
 #elif defined(CONFIG_CPU_SA1100)
 # define CACHE_DSIZE	8192
 #else
 # error Unknown cache size
 #endif

 /*
  * This is the size at which it becomes more efficient to
  * clean the whole cache, rather than using the individual
  * cache line maintenance instructions.
  *
  *  Size  Clean (ticks) Dirty (ticks)
  *   4096   21  20  21    53  55  54
  *   8192   40  41  40   106 100 102
  *  16384   77  77  76   140 140 138
  *  32768  150 149 150   214 216 212 <---
  *  65536  296 297 296   351 358 361
  * 131072  591 591 591   656 657 651
  *  Whole  132 136 132   221 217 207 <---
  */
 #define CACHE_DLIMIT	(CACHE_DSIZE * 4)

 	.data
 	.align	2
 flush_base:
 	.long	FLUSH_BASE
 	.text

 /*
  *	flush_icache_all()
  *
  *	Unconditionally clean and invalidate the entire icache.
  */
 ENTRY(v4wb_flush_icache_all)
 	mov	r0, #0
 	mcr	p15, 0, r0, c7, c5, 0		@ invalidate I cache
 	ret	lr
 ENDPROC(v4wb_flush_icache_all)

 /*
  *	flush_user_cache_all()
  *
  *	Clean and invalidate all cache entries in a particular address
  *	space.
  */
 ENTRY(v4wb_flush_user_cache_all)
 	/* FALLTHROUGH */
 /*
  *	flush_kern_cache_all()
  *
  *	Clean and invalidate the entire cache.
  */
 ENTRY(v4wb_flush_kern_cache_all)
 	mov	ip, #0
 	mcr	p15, 0, ip, c7, c5, 0		@ invalidate I cache
 __flush_whole_cache:
 	ldr	r3, =flush_base
 	ldr	r1, [r3, #0]
 	eor	r1, r1, #CACHE_DSIZE
 	str	r1, [r3, #0]
 	add	r2, r1, #CACHE_DSIZE
 1:	ldr	r3, [r1], #32
 	cmp	r1, r2
 	blo	1b
 #ifdef FLUSH_BASE_MINICACHE
 	add	r2, r2, #FLUSH_BASE_MINICACHE - FLUSH_BASE
 	sub	r1, r2, #512			@ only 512 bytes
 1:	ldr	r3, [r1], #32
 	cmp	r1, r2
 	blo	1b
 #endif
 	mcr	p15, 0, ip, c7, c10, 4		@ drain write buffer
 	ret	lr

 /*
  *	flush_user_cache_range(start, end, flags)
  *
  *	Invalidate a range of cache entries in the specified
  *	address space.
  *
  *	- start - start address (inclusive, page aligned)
  *	- end	- end address (exclusive, page aligned)
  *	- flags	- vma_area_struct flags describing address space
  */
 ENTRY(v4wb_flush_user_cache_range)
 	mov	ip, #0
 	sub	r3, r1, r0			@ calculate total size
 	tst	r2, #VM_EXEC			@ executable region?
 	mcrne	p15, 0, ip, c7, c5, 0		@ invalidate I cache

 	cmp	r3, #CACHE_DLIMIT		@ total size >= limit?
 	bhs	__flush_whole_cache		@ flush whole D cache

 1:	mcr	p15, 0, r0, c7, c10, 1		@ clean D entry
 	mcr	p15, 0, r0, c7, c6, 1		@ invalidate D entry
 	add	r0, r0, #CACHE_DLINESIZE
 	cmp	r0, r1
 	blo	1b
 	tst	r2, #VM_EXEC
 	mcrne	p15, 0, ip, c7, c10, 4		@ drain write buffer
 	ret	lr

 /*
  *	flush_kern_dcache_area(void *addr, size_t size)
  *
  *	Ensure no D cache aliasing occurs, either with itself or
  *	the I cache
  *
  *	- addr	- kernel address
  *	- size	- region size
  */
 ENTRY(v4wb_flush_kern_dcache_area)
 	add	r1, r0, r1
 	/* fall through */

 /*
  *	coherent_kern_range(start, end)
  *
  *	Ensure coherency between the Icache and the Dcache in the
  *	region described by start.  If you have non-snooping
  *	Harvard caches, you need to implement this function.
  *
  *	- start  - virtual start address
  *	- end	 - virtual end address
  */
 ENTRY(v4wb_coherent_kern_range)
 	/* fall through */

 /*
  *	coherent_user_range(start, end)
  *
  *	Ensure coherency between the Icache and the Dcache in the
  *	region described by start.  If you have non-snooping
  *	Harvard caches, you need to implement this function.
  *
  *	- start  - virtual start address
  *	- end	 - virtual end address
  */
 ENTRY(v4wb_coherent_user_range)
 	bic	r0, r0, #CACHE_DLINESIZE - 1
 1:	mcr	p15, 0, r0, c7, c10, 1		@ clean D entry
 	mcr	p15, 0, r0, c7, c6, 1		@ invalidate D entry
 	add	r0, r0, #CACHE_DLINESIZE
 	cmp	r0, r1
 	blo	1b
 	mov	r0, #0
 	mcr	p15, 0, r0, c7, c5, 0		@ invalidate I cache
 	mcr	p15, 0, r0, c7, c10, 4		@ drain WB
 	ret	lr


 /*
  *	dma_inv_range(start, end)
  *
  *	Invalidate (discard) the specified virtual address range.
  *	May not write back any entries.  If 'start' or 'end'
  *	are not cache line aligned, those lines must be written
  *	back.
  *
  *	- start  - virtual start address
  *	- end	 - virtual end address
  */
 v4wb_dma_inv_range:
 	tst	r0, #CACHE_DLINESIZE - 1
 	bic	r0, r0, #CACHE_DLINESIZE - 1
 	mcrne	p15, 0, r0, c7, c10, 1		@ clean D entry
 	tst	r1, #CACHE_DLINESIZE - 1
 	mcrne	p15, 0, r1, c7, c10, 1		@ clean D entry
 1:	mcr	p15, 0, r0, c7, c6, 1		@ invalidate D entry
 	add	r0, r0, #CACHE_DLINESIZE
 	cmp	r0, r1
 	blo	1b
 	mcr	p15, 0, r0, c7, c10, 4		@ drain write buffer
 	ret	lr

 /*
  *	dma_clean_range(start, end)
  *
  *	Clean (write back) the specified virtual address range.
  *
  *	- start  - virtual start address
  *	- end	 - virtual end address
  */
 v4wb_dma_clean_range:
 	bic	r0, r0, #CACHE_DLINESIZE - 1
 1:	mcr	p15, 0, r0, c7, c10, 1		@ clean D entry
 	add	r0, r0, #CACHE_DLINESIZE
 	cmp	r0, r1
 	blo	1b
 	mcr	p15, 0, r0, c7, c10, 4		@ drain write buffer
 	ret	lr

 /*
  *	dma_flush_range(start, end)
  *
  *	Clean and invalidate the specified virtual address range.
  *
  *	- start  - virtual start address
  *	- end	 - virtual end address
  *
  *	This is actually the same as v4wb_coherent_kern_range()
  */
 	.globl	v4wb_dma_flush_range
 	.set	v4wb_dma_flush_range, v4wb_coherent_kern_range

 /*
  *	dma_map_area(start, size, dir)
  *	- start	- kernel virtual start address
  *	- size	- size of region
  *	- dir	- DMA direction
  */
 ENTRY(v4wb_dma_map_area)
 	add	r1, r1, r0
 	cmp	r2, #DMA_TO_DEVICE
 	beq	v4wb_dma_clean_range
 	bcs	v4wb_dma_inv_range
 	b	v4wb_dma_flush_range
 ENDPROC(v4wb_dma_map_area)

 /*
  *	dma_unmap_area(start, size, dir)
  *	- start	- kernel virtual start address
  *	- size	- size of region
  *	- dir	- DMA direction
  */
 ENTRY(v4wb_dma_unmap_area)
 	ret	lr
 ENDPROC(v4wb_dma_unmap_area)

 	.globl	v4wb_flush_kern_cache_louis
 	.equ	v4wb_flush_kern_cache_louis, v4wb_flush_kern_cache_all

 	__INITDATA

 	@ define struct cpu_cache_fns (see <asm/cacheflush.h> and proc-macros.S)
 	define_cache_functions v4wb
	/* SPDX-License-Identifier: GPL-2.0-only */
	/*
	* linux/arch/arm/mm/cache-v4wb.S
	*
	* Copyright (C) 1997-2002 Russell king
	*/
	#include <linux/linkage.h>
	#include <linux/init.h>
	#include <asm/assembler.h>
	#include <asm/memory.h>
	#include <asm/page.h>
	#include "proc-macros.S"

	/*
	* The size of one data cache line.
	*/
	#define CACHE_DLINESIZE 32

	/*
	* The total size of the data cache.
	*/
	#if defined(CONFIG_CPU_SA110)
	# define CACHE_DSIZE 16384
	#elif defined(CONFIG_CPU_SA1100)
	# define CACHE_DSIZE 8192
	#else
	# error Unknown cache size
	#endif

	/*
	* This is the size at which it becomes more efficient to
	* clean the whole cache, rather than using the individual
	* cache line maintenance instructions.
	*
	* Size Clean (ticks) Dirty (ticks)
	* 4096 21 20 21 53 55 54
	* 8192 40 41 40 106 100 102
	* 16384 77 77 76 140 140 138
	* 32768 150 149 150 214 216 212 <---
	* 65536 296 297 296 351 358 361
	* 131072 591 591 591 656 657 651
	* Whole 132 136 132 221 217 207 <---
	*/
	#define CACHE_DLIMIT (CACHE_DSIZE * 4)

	.data
	.align 2
	flush_base:
	.long FLUSH_BASE
	.text

	/*
	* flush_icache_all()
	*
	* Unconditionally clean and invalidate the entire icache.
	*/
	ENTRY(v4wb_flush_icache_all)
	mov r0, #0
	mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache
	ret lr
	ENDPROC(v4wb_flush_icache_all)

	/*
	* flush_user_cache_all()
	*
	* Clean and invalidate all cache entries in a particular address
	* space.
	*/
	ENTRY(v4wb_flush_user_cache_all)
	/* FALLTHROUGH */
	/*
	* flush_kern_cache_all()
	*
	* Clean and invalidate the entire cache.
	*/
	ENTRY(v4wb_flush_kern_cache_all)
	mov ip, #0
	mcr p15, 0, ip, c7, c5, 0 @ invalidate I cache
	__flush_whole_cache:
	ldr r3, =flush_base
	ldr r1, [r3, #0]
	eor r1, r1, #CACHE_DSIZE
	str r1, [r3, #0]
	add r2, r1, #CACHE_DSIZE
	1: ldr r3, [r1], #32
	cmp r1, r2
	blo 1b
	#ifdef FLUSH_BASE_MINICACHE
	add r2, r2, #FLUSH_BASE_MINICACHE - FLUSH_BASE
	sub r1, r2, #512 @ only 512 bytes
	1: ldr r3, [r1], #32
	cmp r1, r2
	blo 1b
	#endif
	mcr p15, 0, ip, c7, c10, 4 @ drain write buffer
	ret lr

	/*
	* flush_user_cache_range(start, end, flags)
	*
	* Invalidate a range of cache entries in the specified
	* address space.
	*
	* - start - start address (inclusive, page aligned)
	* - end - end address (exclusive, page aligned)
	* - flags - vma_area_struct flags describing address space
	*/
	ENTRY(v4wb_flush_user_cache_range)
	mov ip, #0
	sub r3, r1, r0 @ calculate total size
	tst r2, #VM_EXEC @ executable region?
	mcrne p15, 0, ip, c7, c5, 0 @ invalidate I cache

	cmp r3, #CACHE_DLIMIT @ total size >= limit?
	bhs __flush_whole_cache @ flush whole D cache

	1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
	mcr p15, 0, r0, c7, c6, 1 @ invalidate D entry
	add r0, r0, #CACHE_DLINESIZE
	cmp r0, r1
	blo 1b
	tst r2, #VM_EXEC
	mcrne p15, 0, ip, c7, c10, 4 @ drain write buffer
	ret lr

	/*
	* flush_kern_dcache_area(void *addr, size_t size)
	*
	* Ensure no D cache aliasing occurs, either with itself or
	* the I cache
	*
	* - addr - kernel address
	* - size - region size
	*/
	ENTRY(v4wb_flush_kern_dcache_area)
	add r1, r0, r1
	/* fall through */

	/*
	* coherent_kern_range(start, end)
	*
	* Ensure coherency between the Icache and the Dcache in the
	* region described by start. If you have non-snooping
	* Harvard caches, you need to implement this function.
	*
	* - start - virtual start address
	* - end - virtual end address
	*/
	ENTRY(v4wb_coherent_kern_range)
	/* fall through */

	/*
	* coherent_user_range(start, end)
	*
	* Ensure coherency between the Icache and the Dcache in the
	* region described by start. If you have non-snooping
	* Harvard caches, you need to implement this function.
	*
	* - start - virtual start address
	* - end - virtual end address
	*/
	ENTRY(v4wb_coherent_user_range)
	bic r0, r0, #CACHE_DLINESIZE - 1
	1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
	mcr p15, 0, r0, c7, c6, 1 @ invalidate D entry
	add r0, r0, #CACHE_DLINESIZE
	cmp r0, r1
	blo 1b
	mov r0, #0
	mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache
	mcr p15, 0, r0, c7, c10, 4 @ drain WB
	ret lr


	/*
	* dma_inv_range(start, end)
	*
	* Invalidate (discard) the specified virtual address range.
	* May not write back any entries. If 'start' or 'end'
	* are not cache line aligned, those lines must be written
	* back.
	*
	* - start - virtual start address
	* - end - virtual end address
	*/
	v4wb_dma_inv_range:
	tst r0, #CACHE_DLINESIZE - 1
	bic r0, r0, #CACHE_DLINESIZE - 1
	mcrne p15, 0, r0, c7, c10, 1 @ clean D entry
	tst r1, #CACHE_DLINESIZE - 1
	mcrne p15, 0, r1, c7, c10, 1 @ clean D entry
	1: mcr p15, 0, r0, c7, c6, 1 @ invalidate D entry
	add r0, r0, #CACHE_DLINESIZE
	cmp r0, r1
	blo 1b
	mcr p15, 0, r0, c7, c10, 4 @ drain write buffer
	ret lr

	/*
	* dma_clean_range(start, end)
	*
	* Clean (write back) the specified virtual address range.
	*
	* - start - virtual start address
	* - end - virtual end address
	*/
	v4wb_dma_clean_range:
	bic r0, r0, #CACHE_DLINESIZE - 1
	1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
	add r0, r0, #CACHE_DLINESIZE
	cmp r0, r1
	blo 1b
	mcr p15, 0, r0, c7, c10, 4 @ drain write buffer
	ret lr

	/*
	* dma_flush_range(start, end)
	*
	* Clean and invalidate the specified virtual address range.
	*
	* - start - virtual start address
	* - end - virtual end address
	*
	* This is actually the same as v4wb_coherent_kern_range()
	*/
	.globl v4wb_dma_flush_range
	.set v4wb_dma_flush_range, v4wb_coherent_kern_range

	/*
	* dma_map_area(start, size, dir)
	* - start - kernel virtual start address
	* - size - size of region
	* - dir - DMA direction
	*/
	ENTRY(v4wb_dma_map_area)
	add r1, r1, r0
	cmp r2, #DMA_TO_DEVICE
	beq v4wb_dma_clean_range
	bcs v4wb_dma_inv_range
	b v4wb_dma_flush_range
	ENDPROC(v4wb_dma_map_area)

	/*
	* dma_unmap_area(start, size, dir)
	* - start - kernel virtual start address
	* - size - size of region
	* - dir - DMA direction
	*/
	ENTRY(v4wb_dma_unmap_area)
	ret lr
	ENDPROC(v4wb_dma_unmap_area)

	.globl v4wb_flush_kern_cache_louis
	.equ v4wb_flush_kern_cache_louis, v4wb_flush_kern_cache_all

	__INITDATA

	@ define struct cpu_cache_fns (see <asm/cacheflush.h> and proc-macros.S)
	define_cache_functions v4wb