mirror of https://gitee.com/openkylin/linux.git
45 lines
1.2 KiB
C
45 lines
1.2 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
#include <linux/init.h>
|
|
#include <linux/module.h>
|
|
#include <linux/sizes.h>
|
|
#include <asm/page.h>
|
|
#include <asm/addrspace.h>
|
|
|
|
/*
|
|
* This is the offset of the uncached section from its cached alias.
|
|
*
|
|
* Legacy platforms handle trivial transitions between cached and
|
|
* uncached segments by making use of the 1:1 mapping relationship in
|
|
* 512MB lowmem, others via a special uncached mapping.
|
|
*
|
|
* Default value only valid in 29 bit mode, in 32bit mode this will be
|
|
* updated by the early PMB initialization code.
|
|
*/
|
|
unsigned long cached_to_uncached = SZ_512M;
|
|
unsigned long uncached_size = SZ_512M;
|
|
unsigned long uncached_start, uncached_end;
|
|
EXPORT_SYMBOL(uncached_start);
|
|
EXPORT_SYMBOL(uncached_end);
|
|
|
|
int virt_addr_uncached(unsigned long kaddr)
|
|
{
|
|
return (kaddr >= uncached_start) && (kaddr < uncached_end);
|
|
}
|
|
EXPORT_SYMBOL(virt_addr_uncached);
|
|
|
|
void __init uncached_init(void)
|
|
{
|
|
#if defined(CONFIG_29BIT) || !defined(CONFIG_MMU)
|
|
uncached_start = P2SEG;
|
|
#else
|
|
uncached_start = memory_end;
|
|
#endif
|
|
uncached_end = uncached_start + uncached_size;
|
|
}
|
|
|
|
void __init uncached_resize(unsigned long size)
|
|
{
|
|
uncached_size = size;
|
|
uncached_end = uncached_start + uncached_size;
|
|
}
|