1 /* 2 * Copyright (c) 2015 François Tigeot 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/io.h> 32 33 struct io_mapping { 34 resource_size_t base; 35 unsigned long size; 36 unsigned long prot; 37 void *vaddr; 38 }; 39 40 static inline struct io_mapping * 41 io_mapping_create_wc(resource_size_t base, unsigned long size) 42 { 43 struct io_mapping *map; 44 45 map = kmalloc(sizeof(struct io_mapping), M_DRM, M_WAITOK); 46 map->base = base; 47 map->size = size; 48 map->prot = VM_MEMATTR_WRITE_COMBINING; 49 50 map->vaddr = pmap_mapdev_attr(base, size, 51 VM_MEMATTR_WRITE_COMBINING); 52 if (map->vaddr == NULL) 53 return NULL; 54 55 return map; 56 } 57 58 static inline void io_mapping_free(struct io_mapping *mapping) 59 { 60 /* Default memory attribute is write-back */ 61 pmap_mapdev_attr(mapping->base, mapping->size, VM_MEMATTR_WRITE_BACK); 62 kfree(mapping); 63 } 64 65 static inline void * 66 io_mapping_map_atomic_wc(struct io_mapping *mapping, unsigned long offset) 67 { 68 return (void *)PHYS_TO_DMAP(mapping->base + offset); 69 } 70 71 static inline void * 72 io_mapping_map_wc(struct io_mapping *mapping, unsigned long offset) 73 { 74 return io_mapping_map_atomic_wc(mapping, offset); 75 } 76 77 static inline void io_mapping_unmap_atomic(void *vaddr) 78 { 79 } 80 81 #endif /* _LINUX_IOMAPPING_H_ */ 82