linux_dsm_epyc7002/arch/arm/include/asm/cacheflush.h
Lorenzo Pieralisi 031bd879f7 ARM: mm: implement LoUIS API for cache maintenance ops
ARM v7 architecture introduced the concept of cache levels and related
control registers. New processors like A7 and A15 embed an L2 unified cache
controller that becomes part of the cache level hierarchy. Some operations in
the kernel like cpu_suspend and __cpu_disable do not require a flush of the
entire cache hierarchy to DRAM but just the cache levels belonging to the
Level of Unification Inner Shareable (LoUIS), which in most of ARM v7 systems
correspond to L1.

The current cache flushing API used in cpu_suspend and __cpu_disable,
flush_cache_all(), ends up flushing the whole cache hierarchy since for
v7 it cleans and invalidates all cache levels up to Level of Coherency
(LoC) which cripples system performance when used in hot paths like hotplug
and cpuidle.

Therefore a new kernel cache maintenance API must be added to cope with
latest ARM system requirements.

This patch adds flush_cache_louis() to the ARM kernel cache maintenance API.

This function cleans and invalidates all data cache levels up to the
Level of Unification Inner Shareable (LoUIS) and invalidates the instruction
cache for processors that support it (> v7).

This patch also creates an alias of the cache LoUIS function to flush_kern_all
for all processor versions prior to v7, so that the current cache flushing
behaviour is unchanged for those processors.

v7 cache maintenance code implements a cache LoUIS function that cleans and
invalidates the D-cache up to LoUIS and invalidates the I-cache, according
to the new API.

Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
2012-09-25 11:20:25 +01:00

367 lines
12 KiB
C

/*
* arch/arm/include/asm/cacheflush.h
*
* Copyright (C) 1999-2002 Russell King
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#ifndef _ASMARM_CACHEFLUSH_H
#define _ASMARM_CACHEFLUSH_H
#include <linux/mm.h>
#include <asm/glue-cache.h>
#include <asm/shmparam.h>
#include <asm/cachetype.h>
#include <asm/outercache.h>
#define CACHE_COLOUR(vaddr) ((vaddr & (SHMLBA - 1)) >> PAGE_SHIFT)
/*
* This flag is used to indicate that the page pointed to by a pte is clean
* and does not require cleaning before returning it to the user.
*/
#define PG_dcache_clean PG_arch_1
/*
* MM Cache Management
* ===================
*
* The arch/arm/mm/cache-*.S and arch/arm/mm/proc-*.S files
* implement these methods.
*
* Start addresses are inclusive and end addresses are exclusive;
* start addresses should be rounded down, end addresses up.
*
* See Documentation/cachetlb.txt for more information.
* Please note that the implementation of these, and the required
* effects are cache-type (VIVT/VIPT/PIPT) specific.
*
* flush_icache_all()
*
* Unconditionally clean and invalidate the entire icache.
* Currently only needed for cache-v6.S and cache-v7.S, see
* __flush_icache_all for the generic implementation.
*
* flush_kern_all()
*
* Unconditionally clean and invalidate the entire cache.
*
* flush_kern_louis()
*
* Flush data cache levels up to the level of unification
* inner shareable and invalidate the I-cache.
* Only needed from v7 onwards, falls back to flush_cache_all()
* for all other processor versions.
*
* flush_user_all()
*
* Clean and invalidate all user space cache entries
* before a change of page tables.
*
* flush_user_range(start, end, flags)
*
* Clean and invalidate a range of cache entries in the
* specified address space before a change of page tables.
* - start - user start address (inclusive, page aligned)
* - end - user end address (exclusive, page aligned)
* - flags - vma->vm_flags field
*
* coherent_kern_range(start, end)
*
* Ensure coherency between the Icache and the Dcache in the
* region described by start, end. If you have non-snooping
* Harvard caches, you need to implement this function.
* - start - virtual start address
* - end - virtual end address
*
* coherent_user_range(start, end)
*
* Ensure coherency between the Icache and the Dcache in the
* region described by start, end. If you have non-snooping
* Harvard caches, you need to implement this function.
* - start - virtual start address
* - end - virtual end address
*
* flush_kern_dcache_area(kaddr, size)
*
* Ensure that the data held in page is written back.
* - kaddr - page address
* - size - region size
*
* DMA Cache Coherency
* ===================
*
* dma_flush_range(start, end)
*
* Clean and invalidate the specified virtual address range.
* - start - virtual start address
* - end - virtual end address
*/
struct cpu_cache_fns {
void (*flush_icache_all)(void);
void (*flush_kern_all)(void);
void (*flush_kern_louis)(void);
void (*flush_user_all)(void);
void (*flush_user_range)(unsigned long, unsigned long, unsigned int);
void (*coherent_kern_range)(unsigned long, unsigned long);
int (*coherent_user_range)(unsigned long, unsigned long);
void (*flush_kern_dcache_area)(void *, size_t);
void (*dma_map_area)(const void *, size_t, int);
void (*dma_unmap_area)(const void *, size_t, int);
void (*dma_flush_range)(const void *, const void *);
};
/*
* Select the calling method
*/
#ifdef MULTI_CACHE
extern struct cpu_cache_fns cpu_cache;
#define __cpuc_flush_icache_all cpu_cache.flush_icache_all
#define __cpuc_flush_kern_all cpu_cache.flush_kern_all
#define __cpuc_flush_kern_louis cpu_cache.flush_kern_louis
#define __cpuc_flush_user_all cpu_cache.flush_user_all
#define __cpuc_flush_user_range cpu_cache.flush_user_range
#define __cpuc_coherent_kern_range cpu_cache.coherent_kern_range
#define __cpuc_coherent_user_range cpu_cache.coherent_user_range
#define __cpuc_flush_dcache_area cpu_cache.flush_kern_dcache_area
/*
* These are private to the dma-mapping API. Do not use directly.
* Their sole purpose is to ensure that data held in the cache
* is visible to DMA, or data written by DMA to system memory is
* visible to the CPU.
*/
#define dmac_map_area cpu_cache.dma_map_area
#define dmac_unmap_area cpu_cache.dma_unmap_area
#define dmac_flush_range cpu_cache.dma_flush_range
#else
extern void __cpuc_flush_icache_all(void);
extern void __cpuc_flush_kern_all(void);
extern void __cpuc_flush_kern_louis(void);
extern void __cpuc_flush_user_all(void);
extern void __cpuc_flush_user_range(unsigned long, unsigned long, unsigned int);
extern void __cpuc_coherent_kern_range(unsigned long, unsigned long);
extern int __cpuc_coherent_user_range(unsigned long, unsigned long);
extern void __cpuc_flush_dcache_area(void *, size_t);
/*
* These are private to the dma-mapping API. Do not use directly.
* Their sole purpose is to ensure that data held in the cache
* is visible to DMA, or data written by DMA to system memory is
* visible to the CPU.
*/
extern void dmac_map_area(const void *, size_t, int);
extern void dmac_unmap_area(const void *, size_t, int);
extern void dmac_flush_range(const void *, const void *);
#endif
/*
* Copy user data from/to a page which is mapped into a different
* processes address space. Really, we want to allow our "user
* space" model to handle this.
*/
extern void copy_to_user_page(struct vm_area_struct *, struct page *,
unsigned long, void *, const void *, unsigned long);
#define copy_from_user_page(vma, page, vaddr, dst, src, len) \
do { \
memcpy(dst, src, len); \
} while (0)
/*
* Convert calls to our calling convention.
*/
/* Invalidate I-cache */
#define __flush_icache_all_generic() \
asm("mcr p15, 0, %0, c7, c5, 0" \
: : "r" (0));
/* Invalidate I-cache inner shareable */
#define __flush_icache_all_v7_smp() \
asm("mcr p15, 0, %0, c7, c1, 0" \
: : "r" (0));
/*
* Optimized __flush_icache_all for the common cases. Note that UP ARMv7
* will fall through to use __flush_icache_all_generic.
*/
#if (defined(CONFIG_CPU_V7) && \
(defined(CONFIG_CPU_V6) || defined(CONFIG_CPU_V6K))) || \
defined(CONFIG_SMP_ON_UP)
#define __flush_icache_preferred __cpuc_flush_icache_all
#elif __LINUX_ARM_ARCH__ >= 7 && defined(CONFIG_SMP)
#define __flush_icache_preferred __flush_icache_all_v7_smp
#elif __LINUX_ARM_ARCH__ == 6 && defined(CONFIG_ARM_ERRATA_411920)
#define __flush_icache_preferred __cpuc_flush_icache_all
#else
#define __flush_icache_preferred __flush_icache_all_generic
#endif
static inline void __flush_icache_all(void)
{
__flush_icache_preferred();
}
/*
* Flush caches up to Level of Unification Inner Shareable
*/
#define flush_cache_louis() __cpuc_flush_kern_louis()
#define flush_cache_all() __cpuc_flush_kern_all()
static inline void vivt_flush_cache_mm(struct mm_struct *mm)
{
if (cpumask_test_cpu(smp_processor_id(), mm_cpumask(mm)))
__cpuc_flush_user_all();
}
static inline void
vivt_flush_cache_range(struct vm_area_struct *vma, unsigned long start, unsigned long end)
{
struct mm_struct *mm = vma->vm_mm;
if (!mm || cpumask_test_cpu(smp_processor_id(), mm_cpumask(mm)))
__cpuc_flush_user_range(start & PAGE_MASK, PAGE_ALIGN(end),
vma->vm_flags);
}
static inline void
vivt_flush_cache_page(struct vm_area_struct *vma, unsigned long user_addr, unsigned long pfn)
{
struct mm_struct *mm = vma->vm_mm;
if (!mm || cpumask_test_cpu(smp_processor_id(), mm_cpumask(mm))) {
unsigned long addr = user_addr & PAGE_MASK;
__cpuc_flush_user_range(addr, addr + PAGE_SIZE, vma->vm_flags);
}
}
#ifndef CONFIG_CPU_CACHE_VIPT
#define flush_cache_mm(mm) \
vivt_flush_cache_mm(mm)
#define flush_cache_range(vma,start,end) \
vivt_flush_cache_range(vma,start,end)
#define flush_cache_page(vma,addr,pfn) \
vivt_flush_cache_page(vma,addr,pfn)
#else
extern void flush_cache_mm(struct mm_struct *mm);
extern void flush_cache_range(struct vm_area_struct *vma, unsigned long start, unsigned long end);
extern void flush_cache_page(struct vm_area_struct *vma, unsigned long user_addr, unsigned long pfn);
#endif
#define flush_cache_dup_mm(mm) flush_cache_mm(mm)
/*
* flush_cache_user_range is used when we want to ensure that the
* Harvard caches are synchronised for the user space address range.
* This is used for the ARM private sys_cacheflush system call.
*/
#define flush_cache_user_range(start,end) \
__cpuc_coherent_user_range((start) & PAGE_MASK, PAGE_ALIGN(end))
/*
* Perform necessary cache operations to ensure that data previously
* stored within this range of addresses can be executed by the CPU.
*/
#define flush_icache_range(s,e) __cpuc_coherent_kern_range(s,e)
/*
* Perform necessary cache operations to ensure that the TLB will
* see data written in the specified area.
*/
#define clean_dcache_area(start,size) cpu_dcache_clean_area(start, size)
/*
* flush_dcache_page is used when the kernel has written to the page
* cache page at virtual address page->virtual.
*
* If this page isn't mapped (ie, page_mapping == NULL), or it might
* have userspace mappings, then we _must_ always clean + invalidate
* the dcache entries associated with the kernel mapping.
*
* Otherwise we can defer the operation, and clean the cache when we are
* about to change to user space. This is the same method as used on SPARC64.
* See update_mmu_cache for the user space part.
*/
#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
extern void flush_dcache_page(struct page *);
static inline void flush_kernel_vmap_range(void *addr, int size)
{
if ((cache_is_vivt() || cache_is_vipt_aliasing()))
__cpuc_flush_dcache_area(addr, (size_t)size);
}
static inline void invalidate_kernel_vmap_range(void *addr, int size)
{
if ((cache_is_vivt() || cache_is_vipt_aliasing()))
__cpuc_flush_dcache_area(addr, (size_t)size);
}
#define ARCH_HAS_FLUSH_ANON_PAGE
static inline void flush_anon_page(struct vm_area_struct *vma,
struct page *page, unsigned long vmaddr)
{
extern void __flush_anon_page(struct vm_area_struct *vma,
struct page *, unsigned long);
if (PageAnon(page))
__flush_anon_page(vma, page, vmaddr);
}
#define ARCH_HAS_FLUSH_KERNEL_DCACHE_PAGE
static inline void flush_kernel_dcache_page(struct page *page)
{
}
#define flush_dcache_mmap_lock(mapping) \
spin_lock_irq(&(mapping)->tree_lock)
#define flush_dcache_mmap_unlock(mapping) \
spin_unlock_irq(&(mapping)->tree_lock)
#define flush_icache_user_range(vma,page,addr,len) \
flush_dcache_page(page)
/*
* We don't appear to need to do anything here. In fact, if we did, we'd
* duplicate cache flushing elsewhere performed by flush_dcache_page().
*/
#define flush_icache_page(vma,page) do { } while (0)
/*
* flush_cache_vmap() is used when creating mappings (eg, via vmap,
* vmalloc, ioremap etc) in kernel space for pages. On non-VIPT
* caches, since the direct-mappings of these pages may contain cached
* data, we need to do a full cache flush to ensure that writebacks
* don't corrupt data placed into these pages via the new mappings.
*/
static inline void flush_cache_vmap(unsigned long start, unsigned long end)
{
if (!cache_is_vipt_nonaliasing())
flush_cache_all();
else
/*
* set_pte_at() called from vmap_pte_range() does not
* have a DSB after cleaning the cache line.
*/
dsb();
}
static inline void flush_cache_vunmap(unsigned long start, unsigned long end)
{
if (!cache_is_vipt_nonaliasing())
flush_cache_all();
}
#endif