linux-zen-desktop/arch/xtensa/mm/highmem.c

60 lines
1.4 KiB
C

/*
* High memory support for Xtensa architecture
*
* This file is subject to the terms and conditions of the GNU General
* Public License. See the file "COPYING" in the main directory of
* this archive for more details.
*
* Copyright (C) 2014 Cadence Design Systems Inc.
*/
#include <linux/export.h>
#include <linux/highmem.h>
#include <asm/tlbflush.h>
#if DCACHE_WAY_SIZE > PAGE_SIZE
unsigned int last_pkmap_nr_arr[DCACHE_N_COLORS];
wait_queue_head_t pkmap_map_wait_arr[DCACHE_N_COLORS];
static void __init kmap_waitqueues_init(void)
{
unsigned int i;
for (i = 0; i < ARRAY_SIZE(pkmap_map_wait_arr); ++i)
init_waitqueue_head(pkmap_map_wait_arr + i);
}
static inline enum fixed_addresses kmap_idx(int type, unsigned long color)
{
int idx = (type + KM_MAX_IDX * smp_processor_id()) * DCACHE_N_COLORS;
/*
* The fixmap operates top down, so the color offset needs to be
* reverse as well.
*/
return idx + DCACHE_N_COLORS - 1 - color;
}
enum fixed_addresses kmap_local_map_idx(int type, unsigned long pfn)
{
return kmap_idx(type, DCACHE_ALIAS(pfn << PAGE_SHIFT));
}
enum fixed_addresses kmap_local_unmap_idx(int type, unsigned long addr)
{
return kmap_idx(type, DCACHE_ALIAS(addr));
}
#else
static inline void kmap_waitqueues_init(void) { }
#endif
void __init kmap_init(void)
{
/* Check if this memory layout is broken because PKMAP overlaps
* page table.
*/
BUILD_BUG_ON(PKMAP_BASE < TLBTEMP_BASE_1 + TLBTEMP_SIZE);
kmap_waitqueues_init();
}