arch/powerpc/sysdev/dcr.c

   1 /*
   2  * (c) Copyright 2006 Benjamin Herrenschmidt, IBM Corp.
   3  *                    <benh@kernel.crashing.org>
   4  *
   5  *   This program is free software;  you can redistribute it and/or modify
   6  *   it under the terms of the GNU General Public License as published by
   7  *   the Free Software Foundation; either version 2 of the License, or
   8  *   (at your option) any later version.
   9  *
  10  *   This program is distributed in the hope that it will be useful,
  11  *   but WITHOUT ANY WARRANTY;  without even the implied warranty of
  12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
  13  *   the GNU General Public License for more details.
  14  *
  15  *   You should have received a copy of the GNU General Public License
  16  *   along with this program;  if not, write to the Free Software
  17  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  18  */
  19
  20 #undef DEBUG
  21
  22 #include <linux/kernel.h>
  23 #include <asm/prom.h>
  24 #include <asm/dcr.h>
  25
  26 static struct device_node *find_dcr_parent(struct device_node *node)
  27 {
  28         struct device_node *par, *tmp;
  29         const u32 *p;
  30
  31         for (par = of_node_get(node); par;) {
  32                 if (of_get_property(par, "dcr-controller", NULL))
  33                         break;
  34                 p = of_get_property(par, "dcr-parent", NULL);
  35                 tmp = par;
  36                 if (p == NULL)
  37                         par = of_get_parent(par);
  38                 else
  39                         par = of_find_node_by_phandle(*p);
  40                 of_node_put(tmp);
  41         }
  42         return par;
  43 }
  44
  45 #if defined(CONFIG_PPC_DCR_NATIVE) && defined(CONFIG_PPC_DCR_MMIO)
  46
  47 bool dcr_map_ok_generic(dcr_host_t host)
  48 {
  49         if (host.type == DCR_HOST_NATIVE)
  50                 return dcr_map_ok_native(host.host.native);
  51         else if (host.type == DCR_HOST_MMIO)
  52                 return dcr_map_ok_mmio(host.host.mmio);
  53         else
  54                 return 0;
  55 }
  56 EXPORT_SYMBOL_GPL(dcr_map_ok_generic);
  57
  58 dcr_host_t dcr_map_generic(struct device_node *dev,
  59                            unsigned int dcr_n,
  60                            unsigned int dcr_c)
  61 {
  62         dcr_host_t host;
  63         struct device_node *dp;
  64         const char *prop;
  65
  66         host.type = DCR_HOST_INVALID;
  67
  68         dp = find_dcr_parent(dev);
  69         if (dp == NULL)
  70                 return host;
  71
  72         prop = of_get_property(dp, "dcr-access-method", NULL);
  73
  74         pr_debug("dcr_map_generic(dcr-access-method = %s)\n", prop);
  75
  76         if (!strcmp(prop, "native")) {
  77                 host.type = DCR_HOST_NATIVE;
  78                 host.host.native = dcr_map_native(dev, dcr_n, dcr_c);
  79         } else if (!strcmp(prop, "mmio")) {
  80                 host.type = DCR_HOST_MMIO;
  81                 host.host.mmio = dcr_map_mmio(dev, dcr_n, dcr_c);
  82         }
  83
  84         of_node_put(dp);
  85         return host;
  86 }
  87 EXPORT_SYMBOL_GPL(dcr_map_generic);
  88
  89 void dcr_unmap_generic(dcr_host_t host, unsigned int dcr_c)
  90 {
  91         if (host.type == DCR_HOST_NATIVE)
  92                 dcr_unmap_native(host.host.native, dcr_c);
  93         else if (host.type == DCR_HOST_MMIO)
  94                 dcr_unmap_mmio(host.host.mmio, dcr_c);
  95         else /* host.type == DCR_HOST_INVALID */
  96                 WARN_ON(true);
  97 }
  98 EXPORT_SYMBOL_GPL(dcr_unmap_generic);
  99
 100 u32 dcr_read_generic(dcr_host_t host, unsigned int dcr_n)
 101 {
 102         if (host.type == DCR_HOST_NATIVE)
 103                 return dcr_read_native(host.host.native, dcr_n);
 104         else if (host.type == DCR_HOST_MMIO)
 105                 return dcr_read_mmio(host.host.mmio, dcr_n);
 106         else /* host.type == DCR_HOST_INVALID */
 107                 WARN_ON(true);
 108         return 0;
 109 }
 110 EXPORT_SYMBOL_GPL(dcr_read_generic);
 111
 112 void dcr_write_generic(dcr_host_t host, unsigned int dcr_n, u32 value)
 113 {
 114         if (host.type == DCR_HOST_NATIVE)
 115                 dcr_write_native(host.host.native, dcr_n, value);
 116         else if (host.type == DCR_HOST_MMIO)
 117                 dcr_write_mmio(host.host.mmio, dcr_n, value);
 118         else /* host.type == DCR_HOST_INVALID */
 119                 WARN_ON(true);
 120 }
 121 EXPORT_SYMBOL_GPL(dcr_write_generic);
 122
 123 #endif /* defined(CONFIG_PPC_DCR_NATIVE) && defined(CONFIG_PPC_DCR_MMIO) */
 124
 125 unsigned int dcr_resource_start(struct device_node *np, unsigned int index)
 126 {
 127         unsigned int ds;
 128         const u32 *dr = of_get_property(np, "dcr-reg", &ds);
 129
 130         if (dr == NULL || ds & 1 || index >= (ds / 8))
 131                 return 0;
 132
 133         return dr[index * 2];
 134 }
 135 EXPORT_SYMBOL_GPL(dcr_resource_start);
 136
 137 unsigned int dcr_resource_len(struct device_node *np, unsigned int index)
 138 {
 139         unsigned int ds;
 140         const u32 *dr = of_get_property(np, "dcr-reg", &ds);
 141
 142         if (dr == NULL || ds & 1 || index >= (ds / 8))
 143                 return 0;
 144
 145         return dr[index * 2 + 1];
 146 }
 147 EXPORT_SYMBOL_GPL(dcr_resource_len);
 148
 149 #ifdef CONFIG_PPC_DCR_MMIO
 150
 151 u64 of_translate_dcr_address(struct device_node *dev,
 152                              unsigned int dcr_n,
 153                              unsigned int *out_stride)
 154 {
 155         struct device_node *dp;
 156         const u32 *p;
 157         unsigned int stride;
 158         u64 ret = OF_BAD_ADDR;
 159
 160         dp = find_dcr_parent(dev);
 161         if (dp == NULL)
 162                 return OF_BAD_ADDR;
 163
 164         /* Stride is not properly defined yet, default to 0x10 for Axon */
 165         p = of_get_property(dp, "dcr-mmio-stride", NULL);
 166         stride = (p == NULL) ? 0x10 : *p;
 167
 168         /* XXX FIXME: Which property name is to use of the 2 following ? */
 169         p = of_get_property(dp, "dcr-mmio-range", NULL);
 170         if (p == NULL)
 171                 p = of_get_property(dp, "dcr-mmio-space", NULL);
 172         if (p == NULL)
 173                 goto done;
 174
 175         /* Maybe could do some better range checking here */
 176         ret = of_translate_address(dp, p);
 177         if (ret != OF_BAD_ADDR)
 178                 ret += (u64)(stride) * (u64)dcr_n;
 179         if (out_stride)
 180                 *out_stride = stride;
 181
 182  done:
 183         of_node_put(dp);
 184         return ret;
 185 }
 186
 187 dcr_host_mmio_t dcr_map_mmio(struct device_node *dev,
 188                              unsigned int dcr_n,
 189                              unsigned int dcr_c)
 190 {
 191         dcr_host_mmio_t ret = { .token = NULL, .stride = 0, .base = dcr_n };
 192         u64 addr;
 193
 194         pr_debug("dcr_map(%s, 0x%x, 0x%x)\n",
 195                  dev->full_name, dcr_n, dcr_c);
 196
 197         addr = of_translate_dcr_address(dev, dcr_n, &ret.stride);
 198         pr_debug("translates to addr: 0x%llx, stride: 0x%x\n",
 199                  (unsigned long long) addr, ret.stride);
 200         if (addr == OF_BAD_ADDR)
 201                 return ret;
 202         pr_debug("mapping 0x%x bytes\n", dcr_c * ret.stride);
 203         ret.token = ioremap(addr, dcr_c * ret.stride);
 204         if (ret.token == NULL)
 205                 return ret;
 206         pr_debug("mapped at 0x%p -> base is 0x%p\n",
 207                  ret.token, ret.token - dcr_n * ret.stride);
 208         ret.token -= dcr_n * ret.stride;
 209         return ret;
 210 }
 211 EXPORT_SYMBOL_GPL(dcr_map_mmio);
 212
 213 void dcr_unmap_mmio(dcr_host_mmio_t host, unsigned int dcr_c)
 214 {
 215         dcr_host_mmio_t h = host;
 216
 217         if (h.token == NULL)
 218                 return;
 219         h.token += host.base * h.stride;
 220         iounmap(h.token);
 221         h.token = NULL;
 222 }
 223 EXPORT_SYMBOL_GPL(dcr_unmap_mmio);
 224
 225 #endif /* defined(CONFIG_PPC_DCR_MMIO) */
 226
 227 #ifdef CONFIG_PPC_DCR_NATIVE
 228 DEFINE_SPINLOCK(dcr_ind_lock);
 229 #endif  /* defined(CONFIG_PPC_DCR_NATIVE) */
 230