highmem.c (1480B)
1/* 2 * High memory support for Xtensa architecture 3 * 4 * This file is subject to the terms and conditions of the GNU General 5 * Public License. See the file "COPYING" in the main directory of 6 * this archive for more details. 7 * 8 * Copyright (C) 2014 Cadence Design Systems Inc. 9 */ 10 11#include <linux/export.h> 12#include <linux/highmem.h> 13#include <asm/tlbflush.h> 14 15#if DCACHE_WAY_SIZE > PAGE_SIZE 16unsigned int last_pkmap_nr_arr[DCACHE_N_COLORS]; 17wait_queue_head_t pkmap_map_wait_arr[DCACHE_N_COLORS]; 18 19static void __init kmap_waitqueues_init(void) 20{ 21 unsigned int i; 22 23 for (i = 0; i < ARRAY_SIZE(pkmap_map_wait_arr); ++i) 24 init_waitqueue_head(pkmap_map_wait_arr + i); 25} 26 27static inline enum fixed_addresses kmap_idx(int type, unsigned long color) 28{ 29 int idx = (type + KM_MAX_IDX * smp_processor_id()) * DCACHE_N_COLORS; 30 31 /* 32 * The fixmap operates top down, so the color offset needs to be 33 * reverse as well. 34 */ 35 return idx + DCACHE_N_COLORS - 1 - color; 36} 37 38enum fixed_addresses kmap_local_map_idx(int type, unsigned long pfn) 39{ 40 return kmap_idx(type, DCACHE_ALIAS(pfn << PAGE_SHIFT)); 41} 42 43enum fixed_addresses kmap_local_unmap_idx(int type, unsigned long addr) 44{ 45 return kmap_idx(type, DCACHE_ALIAS(addr)); 46} 47 48#else 49static inline void kmap_waitqueues_init(void) { } 50#endif 51 52void __init kmap_init(void) 53{ 54 /* Check if this memory layout is broken because PKMAP overlaps 55 * page table. 56 */ 57 BUILD_BUG_ON(PKMAP_BASE < TLBTEMP_BASE_1 + TLBTEMP_SIZE); 58 kmap_waitqueues_init(); 59}