1 /* 2 * Copyright (c) 2015-2019 François Tigeot <ftigeot@wolfpond.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice unmodified, this list of conditions, and the following 10 * disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 27 #ifndef _LINUX_IOMAPPING_H_ 28 #define _LINUX_IOMAPPING_H_ 29 30 #include <linux/types.h> 31 #include <linux/slab.h> 32 #include <linux/bug.h> 33 #include <linux/io.h> 34 #include <asm/page.h> 35 36 struct io_mapping { 37 resource_size_t base; 38 unsigned long size; 39 unsigned long prot; 40 void *vaddr; 41 }; 42 43 static inline struct io_mapping * 44 io_mapping_create_wc(resource_size_t base, unsigned long size) 45 { 46 struct io_mapping *map; 47 48 map = kmalloc(sizeof(struct io_mapping), M_DRM, M_WAITOK); 49 map->base = base; 50 map->size = size; 51 map->prot = VM_MEMATTR_WRITE_COMBINING; 52 53 map->vaddr = pmap_mapdev_attr(base, size, 54 VM_MEMATTR_WRITE_COMBINING); 55 if (map->vaddr == NULL) 56 return NULL; 57 58 return map; 59 } 60 61 static inline void io_mapping_free(struct io_mapping *mapping) 62 { 63 /* Default memory attribute is write-back */ 64 pmap_mapdev_attr(mapping->base, mapping->size, VM_MEMATTR_WRITE_BACK); 65 kfree(mapping); 66 } 67 68 static inline void * 69 io_mapping_map_atomic_wc(struct io_mapping *mapping, unsigned long offset) 70 { 71 return (void *)PHYS_TO_DMAP(mapping->base + offset); 72 } 73 74 static inline void * 75 io_mapping_map_wc(struct io_mapping *mapping, 76 unsigned long offset, 77 unsigned long size) 78 { 79 return (void *)PHYS_TO_DMAP(mapping->base + offset); 80 } 81 82 static inline void 83 io_mapping_unmap(void *vaddr) 84 { 85 } 86 87 static inline void 88 io_mapping_unmap_atomic(void *vaddr) 89 { 90 } 91 92 #endif /* _LINUX_IOMAPPING_H_ */ 93