cacheflush.h
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _METAG_CACHEFLUSH_H
#define _METAG_CACHEFLUSH_H
#include <linux/mm.h>
#include <linux/sched.h>
#include <linux/io.h>
#include <asm/l2cache.h>
#include <asm/metag_isa.h>
#include <asm/metag_mem.h>
void metag_cache_probe(void);
void metag_data_cache_flush_all(const void *start);
void metag_code_cache_flush_all(const void *start);
/*
* Routines to flush physical cache lines that may be used to cache data or code
* normally accessed via the linear address range supplied. The region flushed
* must either lie in local or global address space determined by the top bit of
* the pStart address. If Bytes is >= 4K then the whole of the related cache
* state will be flushed rather than a limited range.
*/
void metag_data_cache_flush(const void *start, int bytes);
void metag_code_cache_flush(const void *start, int bytes);
#ifdef CONFIG_METAG_META12
/* Write through, virtually tagged, split I/D cache. */
static inline void __flush_cache_all(void)
{
metag_code_cache_flush_all((void *) PAGE_OFFSET);
metag_data_cache_flush_all((void *) PAGE_OFFSET);
}
#define flush_cache_all() __flush_cache_all()
/* flush the entire user address space referenced in this mm structure */
static inline void flush_cache_mm(struct mm_struct *mm)
{
if (mm == current->mm)
__flush_cache_all();
}
#define flush_cache_dup_mm(mm) flush_cache_mm(mm)
/* flush a range of addresses from this mm */
static inline void flush_cache_range(struct vm_area_struct *vma,
unsigned long start, unsigned long end)
{
flush_cache_mm(vma->vm_mm);
}
static inline void flush_cache_page(struct vm_area_struct *vma,
unsigned long vmaddr, unsigned long pfn)
{
flush_cache_mm(vma->vm_mm);
}
#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
static inline void flush_dcache_page(struct page *page)
{
metag_data_cache_flush_all((void *) PAGE_OFFSET);
}
#define flush_dcache_mmap_lock(mapping) do { } while (0)
#define flush_dcache_mmap_unlock(mapping) do { } while (0)
static inline void flush_icache_page(struct vm_area_struct *vma,
struct page *page)
{
metag_code_cache_flush(page_to_virt(page), PAGE_SIZE);
}
static inline void flush_cache_vmap(unsigned long start, unsigned long end)
{
metag_data_cache_flush_all((void *) PAGE_OFFSET);
}
static inline void flush_cache_vunmap(unsigned long start, unsigned long end)
{
metag_data_cache_flush_all((void *) PAGE_OFFSET);
}
#else
/* Write through, physically tagged, split I/D cache. */
#define flush_cache_all() do { } while (0)
#define flush_cache_mm(mm) do { } while (0)
#define flush_cache_dup_mm(mm) do { } while (0)
#define flush_cache_range(vma, start, end) do { } while (0)
#define flush_cache_page(vma, vmaddr, pfn) do { } while (0)
#define flush_dcache_mmap_lock(mapping) do { } while (0)
#define flush_dcache_mmap_unlock(mapping) do { } while (0)
#define flush_icache_page(vma, pg) do { } while (0)
#define flush_cache_vmap(start, end) do { } while (0)
#define flush_cache_vunmap(start, end) do { } while (0)
#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
static inline void flush_dcache_page(struct page *page)
{
/* FIXME: We can do better than this. All we are trying to do is
* make the i-cache coherent, we should use the PG_arch_1 bit like
* e.g. powerpc.
*/
#ifdef CONFIG_SMP
metag_out32(1, SYSC_ICACHE_FLUSH);
#else
metag_code_cache_flush_all((void *) PAGE_OFFSET);
#endif
}
#endif
/* Push n pages at kernel virtual address and clear the icache */
static inline void flush_icache_range(unsigned long address,
unsigned long endaddr)
{
#ifdef CONFIG_SMP
metag_out32(1, SYSC_ICACHE_FLUSH);
#else
metag_code_cache_flush((void *) address, endaddr - address);
#endif
}
static inline void flush_cache_sigtramp(unsigned long addr, int size)
{
/*
* Flush the icache in case there was previously some code
* fetched from this address, perhaps a previous sigtramp.
*
* We don't need to flush the dcache, it's write through and
* we just wrote the sigtramp code through it.
*/
#ifdef CONFIG_SMP
metag_out32(1, SYSC_ICACHE_FLUSH);
#else
metag_code_cache_flush((void *) addr, size);
#endif
}
#ifdef CONFIG_METAG_L2C
/*
* Perform a single specific CACHEWD operation on an address, masking lower bits
* of address first.
*/
static inline void cachewd_line(void *addr, unsigned int data)
{
unsigned long masked = (unsigned long)addr & -0x40;
__builtin_meta2_cachewd((void *)masked, data);
}
/* Perform a certain CACHEW op on each cache line in a range */
static inline void cachew_region_op(void *start, unsigned long size,
unsigned int op)
{
unsigned long offset = (unsigned long)start & 0x3f;
int i;
if (offset) {
size += offset;
start -= offset;
}
i = (size - 1) >> 6;
do {
__builtin_meta2_cachewd(start, op);
start += 0x40;
} while (i--);
}
/* prevent write fence and flushbacks being reordered in L2 */
static inline void l2c_fence_flush(void *addr)
{
/*
* Synchronise by reading back and re-flushing.
* It is assumed this access will miss, as the caller should have just
* flushed the cache line.
*/
(void)(volatile u8 *)addr;
cachewd_line(addr, CACHEW_FLUSH_L1D_L2);
}
/* prevent write fence and writebacks being reordered in L2 */
static inline void l2c_fence(void *addr)
{
/*
* A write back has occurred, but not necessarily an invalidate, so the
* readback in l2c_fence_flush() would hit in the cache and have no
* effect. Therefore fully flush the line first.
*/
cachewd_line(addr, CACHEW_FLUSH_L1D_L2);
l2c_fence_flush(addr);
}
/* Used to keep memory consistent when doing DMA. */
static inline void flush_dcache_region(void *start, unsigned long size)
{
/* metag_data_cache_flush won't flush L2 cache lines if size >= 4096 */
if (meta_l2c_is_enabled()) {
cachew_region_op(start, size, CACHEW_FLUSH_L1D_L2);
if (meta_l2c_is_writeback())
l2c_fence_flush(start + size - 1);
} else {
metag_data_cache_flush(start, size);
}
}
/* Write back dirty lines to memory (or do nothing if no writeback caches) */
static inline void writeback_dcache_region(void *start, unsigned long size)
{
if (meta_l2c_is_enabled() && meta_l2c_is_writeback()) {
cachew_region_op(start, size, CACHEW_WRITEBACK_L1D_L2);
l2c_fence(start + size - 1);
}
}
/* Invalidate (may also write back if necessary) */
static inline void invalidate_dcache_region(void *start, unsigned long size)
{
if (meta_l2c_is_enabled())
cachew_region_op(start, size, CACHEW_INVALIDATE_L1D_L2);
else
metag_data_cache_flush(start, size);
}
#else
#define flush_dcache_region(s, l) metag_data_cache_flush((s), (l))
#define writeback_dcache_region(s, l) do {} while (0)
#define invalidate_dcache_region(s, l) flush_dcache_region((s), (l))
#endif
static inline void copy_to_user_page(struct vm_area_struct *vma,
struct page *page, unsigned long vaddr,
void *dst, const void *src,
unsigned long len)
{
memcpy(dst, src, len);
flush_icache_range((unsigned long)dst, (unsigned long)dst + len);
}
static inline void copy_from_user_page(struct vm_area_struct *vma,
struct page *page, unsigned long vaddr,
void *dst, const void *src,
unsigned long len)
{
memcpy(dst, src, len);
}
#endif /* _METAG_CACHEFLUSH_H */