drivers/core/regmap.c

   1 /*
   2  * Copyright (c) 2015 Google, Inc
   3  * Written by Simon Glass <sjg@chromium.org>
   4  *
   5  * SPDX-License-Identifier:     GPL-2.0+
   6  */
   7
   8 #include <common.h>
   9 #include <dm.h>
  10 #include <errno.h>
  11 #include <libfdt.h>
  12 #include <malloc.h>
  13 #include <mapmem.h>
  14 #include <regmap.h>
  15
  16 #include <asm/io.h>
  17
  18 DECLARE_GLOBAL_DATA_PTR;
  19
  20 static struct regmap *regmap_alloc_count(int count)
  21 {
  22         struct regmap *map;
  23
  24         map = malloc(sizeof(struct regmap));
  25         if (!map)
  26                 return NULL;
  27         if (count <= 1) {
  28                 map->range = &map->base_range;
  29         } else {
  30                 map->range = malloc(count * sizeof(struct regmap_range));
  31                 if (!map->range) {
  32                         free(map);
  33                         return NULL;
  34                 }
  35         }
  36         map->range_count = count;
  37
  38         return map;
  39 }
  40
  41 #if CONFIG_IS_ENABLED(OF_PLATDATA)
  42 int regmap_init_mem_platdata(struct udevice *dev, u32 *reg, int count,
  43                              struct regmap **mapp)
  44 {
  45         struct regmap_range *range;
  46         struct regmap *map;
  47
  48         map = regmap_alloc_count(count);
  49         if (!map)
  50                 return -ENOMEM;
  51
  52         map->base = *reg;
  53         for (range = map->range; count > 0; reg += 2, range++, count--) {
  54                 range->start = *reg;
  55                 range->size = reg[1];
  56         }
  57
  58         *mapp = map;
  59
  60         return 0;
  61 }
  62 #else
  63 int regmap_init_mem(struct udevice *dev, struct regmap **mapp)
  64 {
  65         const void *blob = gd->fdt_blob;
  66         struct regmap_range *range;
  67         const fdt32_t *cell;
  68         struct regmap *map;
  69         int count;
  70         int addr_len, size_len, both_len;
  71         int parent;
  72         int len;
  73
  74         parent = dev->parent->of_offset;
  75         addr_len = fdt_address_cells(blob, parent);
  76         size_len = fdt_size_cells(blob, parent);
  77         both_len = addr_len + size_len;
  78
  79         cell = fdt_getprop(blob, dev->of_offset, "reg", &len);
  80         len /= sizeof(*cell);
  81         count = len / both_len;
  82         if (!cell || !count)
  83                 return -EINVAL;
  84
  85         map = regmap_alloc_count(count);
  86         if (!map)
  87                 return -ENOMEM;
  88
  89         map->base = fdtdec_get_number(cell, addr_len);
  90
  91         for (range = map->range; count > 0;
  92              count--, cell += both_len, range++) {
  93                 range->start = fdtdec_get_number(cell, addr_len);
  94                 range->size = fdtdec_get_number(cell + addr_len, size_len);
  95         }
  96
  97         *mapp = map;
  98
  99         return 0;
 100 }
 101 #endif
 102
 103 void *regmap_get_range(struct regmap *map, unsigned int range_num)
 104 {
 105         struct regmap_range *range;
 106
 107         if (range_num >= map->range_count)
 108                 return NULL;
 109         range = &map->range[range_num];
 110
 111         return map_sysmem(range->start, range->size);
 112 }
 113
 114 int regmap_uninit(struct regmap *map)
 115 {
 116         if (map->range_count > 1)
 117                 free(map->range);
 118         free(map);
 119
 120         return 0;
 121 }
 122
 123 int regmap_read(struct regmap *map, uint offset, uint *valp)
 124 {
 125         uint32_t *ptr = map_physmem(map->base + offset, 4, MAP_NOCACHE);
 126
 127         *valp = le32_to_cpu(readl(ptr));
 128
 129         return 0;
 130 }
 131
 132 int regmap_write(struct regmap *map, uint offset, uint val)
 133 {
 134         uint32_t *ptr = map_physmem(map->base + offset, 4, MAP_NOCACHE);
 135
 136         writel(cpu_to_le32(val), ptr);
 137
 138         return 0;
 139 }