swh:1:snp:77163734605b0ec556b01d897b7bb4a7e30d46b6
Tip revision: 4fe89d07dcc2804c8b562f6c7896a45643d34b2f authored by Linus Torvalds on 02 October 2022, 21:09:07 UTC
Linux 6.0
Linux 6.0
Tip revision: 4fe89d0
memory.c
// SPDX-License-Identifier: GPL-2.0
/*
* linux/arch/m68k/mm/memory.c
*
* Copyright (C) 1995 Hamish Macdonald
*/
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/init.h>
#include <linux/pagemap.h>
#include <linux/gfp.h>
#include <asm/setup.h>
#include <asm/page.h>
#include <asm/traps.h>
#include <asm/machdep.h>
/* invalidate page in both caches */
static inline void clear040(unsigned long paddr)
{
asm volatile (
"nop\n\t"
".chip 68040\n\t"
"cinvp %%bc,(%0)\n\t"
".chip 68k"
: : "a" (paddr));
}
/* invalidate page in i-cache */
static inline void cleari040(unsigned long paddr)
{
asm volatile (
"nop\n\t"
".chip 68040\n\t"
"cinvp %%ic,(%0)\n\t"
".chip 68k"
: : "a" (paddr));
}
/* push page in both caches */
/* RZ: cpush %bc DOES invalidate %ic, regardless of DPI */
static inline void push040(unsigned long paddr)
{
asm volatile (
"nop\n\t"
".chip 68040\n\t"
"cpushp %%bc,(%0)\n\t"
".chip 68k"
: : "a" (paddr));
}
/* push and invalidate page in both caches, must disable ints
* to avoid invalidating valid data */
static inline void pushcl040(unsigned long paddr)
{
unsigned long flags;
local_irq_save(flags);
push040(paddr);
if (CPU_IS_060)
clear040(paddr);
local_irq_restore(flags);
}
/*
* 040: Hit every page containing an address in the range paddr..paddr+len-1.
* (Low order bits of the ea of a CINVP/CPUSHP are "don't care"s).
* Hit every page until there is a page or less to go. Hit the next page,
* and the one after that if the range hits it.
*/
/* ++roman: A little bit more care is required here: The CINVP instruction
* invalidates cache entries WITHOUT WRITING DIRTY DATA BACK! So the beginning
* and the end of the region must be treated differently if they are not
* exactly at the beginning or end of a page boundary. Else, maybe too much
* data becomes invalidated and thus lost forever. CPUSHP does what we need:
* it invalidates the page after pushing dirty data to memory. (Thanks to Jes
* for discovering the problem!)
*/
/* ... but on the '060, CPUSH doesn't invalidate (for us, since we have set
* the DPI bit in the CACR; would it cause problems with temporarily changing
* this?). So we have to push first and then additionally to invalidate.
*/
/*
* cache_clear() semantics: Clear any cache entries for the area in question,
* without writing back dirty entries first. This is useful if the data will
* be overwritten anyway, e.g. by DMA to memory. The range is defined by a
* _physical_ address.
*/
void cache_clear (unsigned long paddr, int len)
{
if (CPU_IS_COLDFIRE) {
clear_cf_bcache(0, DCACHE_MAX_ADDR);
} else if (CPU_IS_040_OR_060) {
int tmp;
/*
* We need special treatment for the first page, in case it
* is not page-aligned. Page align the addresses to work
* around bug I17 in the 68060.
*/
if ((tmp = -paddr & (PAGE_SIZE - 1))) {
pushcl040(paddr & PAGE_MASK);
if ((len -= tmp) <= 0)
return;
paddr += tmp;
}
tmp = PAGE_SIZE;
paddr &= PAGE_MASK;
while ((len -= tmp) >= 0) {
clear040(paddr);
paddr += tmp;
}
if ((len += tmp))
/* a page boundary gets crossed at the end */
pushcl040(paddr);
}
else /* 68030 or 68020 */
asm volatile ("movec %/cacr,%/d0\n\t"
"oriw %0,%/d0\n\t"
"movec %/d0,%/cacr"
: : "i" (FLUSH_I_AND_D)
: "d0");
#ifdef CONFIG_M68K_L2_CACHE
if(mach_l2_flush)
mach_l2_flush(0);
#endif
}
EXPORT_SYMBOL(cache_clear);
/*
* cache_push() semantics: Write back any dirty cache data in the given area,
* and invalidate the range in the instruction cache. It needs not (but may)
* invalidate those entries also in the data cache. The range is defined by a
* _physical_ address.
*/
void cache_push (unsigned long paddr, int len)
{
if (CPU_IS_COLDFIRE) {
flush_cf_bcache(0, DCACHE_MAX_ADDR);
} else if (CPU_IS_040_OR_060) {
int tmp = PAGE_SIZE;
/*
* on 68040 or 68060, push cache lines for pages in the range;
* on the '040 this also invalidates the pushed lines, but not on
* the '060!
*/
len += paddr & (PAGE_SIZE - 1);
/*
* Work around bug I17 in the 68060 affecting some instruction
* lines not being invalidated properly.
*/
paddr &= PAGE_MASK;
do {
push040(paddr);
paddr += tmp;
} while ((len -= tmp) > 0);
}
/*
* 68030/68020 have no writeback cache. On the other hand,
* cache_push is actually a superset of cache_clear (the lines
* get written back and invalidated), so we should make sure
* to perform the corresponding actions. After all, this is getting
* called in places where we've just loaded code, or whatever, so
* flushing the icache is appropriate; flushing the dcache shouldn't
* be required.
*/
else /* 68030 or 68020 */
asm volatile ("movec %/cacr,%/d0\n\t"
"oriw %0,%/d0\n\t"
"movec %/d0,%/cacr"
: : "i" (FLUSH_I)
: "d0");
#ifdef CONFIG_M68K_L2_CACHE
if(mach_l2_flush)
mach_l2_flush(1);
#endif
}
EXPORT_SYMBOL(cache_push);