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 #ifdef CONFIG_PPC_DCR_MMIO
  27 static struct device_node *find_dcr_parent(struct device_node *node)
  28 {
  29         struct device_node *par, *tmp;
  30         const u32 *p;
  31
  32         for (par = of_node_get(node); par;) {
  33                 if (of_get_property(par, "dcr-controller", NULL))
  34                         break;
  35                 p = of_get_property(par, "dcr-parent", NULL);
  36                 tmp = par;
  37                 if (p == NULL)
  38                         par = of_get_parent(par);
  39                 else
  40                         par = of_find_node_by_phandle(*p);
  41                 of_node_put(tmp);
  42         }
  43         return par;
  44 }
  45 #endif
  46
  47 #if defined(CONFIG_PPC_DCR_NATIVE) && defined(CONFIG_PPC_DCR_MMIO)
  48
  49 bool dcr_map_ok_generic(dcr_host_t host)
  50 {
  51         if (host.type == DCR_HOST_NATIVE)
  52                 return dcr_map_ok_native(host.host.native);
  53         else if (host.type == DCR_HOST_MMIO)
  54                 return dcr_map_ok_mmio(host.host.mmio);
  55         else
  56                 return 0;
  57 }
  58 EXPORT_SYMBOL_GPL(dcr_map_ok_generic);
  59
  60 dcr_host_t dcr_map_generic(struct device_node *dev,
  61                            unsigned int dcr_n,
  62                            unsigned int dcr_c)
  63 {
  64         dcr_host_t host;
  65         struct device_node *dp;
  66         const char *prop;
  67
  68         host.type = DCR_HOST_INVALID;
  69
  70         dp = find_dcr_parent(dev);
  71         if (dp == NULL)
  72                 return host;
  73
  74         prop = of_get_property(dp, "dcr-access-method", NULL);
  75
  76         pr_debug("dcr_map_generic(dcr-access-method = %s)\n", prop);
  77
  78         if (!strcmp(prop, "native")) {
  79                 host.type = DCR_HOST_NATIVE;
  80                 host.host.native = dcr_map_native(dev, dcr_n, dcr_c);
  81         } else if (!strcmp(prop, "mmio")) {
  82                 host.type = DCR_HOST_MMIO;
  83                 host.host.mmio = dcr_map_mmio(dev, dcr_n, dcr_c);
  84         }
  85
  86         of_node_put(dp);
  87         return host;
  88 }
  89 EXPORT_SYMBOL_GPL(dcr_map_generic);
  90
  91 void dcr_unmap_generic(dcr_host_t host, unsigned int dcr_c)
  92 {
  93         if (host.type == DCR_HOST_NATIVE)
  94                 dcr_unmap_native(host.host.native, dcr_c);
  95         else if (host.type == DCR_HOST_MMIO)
  96                 dcr_unmap_mmio(host.host.mmio, dcr_c);
  97         else /* host.type == DCR_HOST_INVALID */
  98                 WARN_ON(true);
  99 }
 100 EXPORT_SYMBOL_GPL(dcr_unmap_generic);
 101
 102 u32 dcr_read_generic(dcr_host_t host, unsigned int dcr_n)
 103 {
 104         if (host.type == DCR_HOST_NATIVE)
 105                 return dcr_read_native(host.host.native, dcr_n);
 106         else if (host.type == DCR_HOST_MMIO)
 107                 return dcr_read_mmio(host.host.mmio, dcr_n);
 108         else /* host.type == DCR_HOST_INVALID */
 109                 WARN_ON(true);
 110         return 0;
 111 }
 112 EXPORT_SYMBOL_GPL(dcr_read_generic);
 113
 114 void dcr_write_generic(dcr_host_t host, unsigned int dcr_n, u32 value)
 115 {
 116         if (host.type == DCR_HOST_NATIVE)
 117                 dcr_write_native(host.host.native, dcr_n, value);
 118         else if (host.type == DCR_HOST_MMIO)
 119                 dcr_write_mmio(host.host.mmio, dcr_n, value);
 120         else /* host.type == DCR_HOST_INVALID */
 121                 WARN_ON(true);
 122 }
 123 EXPORT_SYMBOL_GPL(dcr_write_generic);
 124
 125 #endif /* defined(CONFIG_PPC_DCR_NATIVE) && defined(CONFIG_PPC_DCR_MMIO) */
 126
 127 unsigned int dcr_resource_start(const struct device_node *np,
 128                                 unsigned int index)
 129 {
 130         unsigned int ds;
 131         const u32 *dr = of_get_property(np, "dcr-reg", &ds);
 132
 133         if (dr == NULL || ds & 1 || index >= (ds / 8))
 134                 return 0;
 135
 136         return dr[index * 2];
 137 }
 138 EXPORT_SYMBOL_GPL(dcr_resource_start);
 139
 140 unsigned int dcr_resource_len(const struct device_node *np, unsigned int index)
 141 {
 142         unsigned int ds;
 143         const u32 *dr = of_get_property(np, "dcr-reg", &ds);
 144
 145         if (dr == NULL || ds & 1 || index >= (ds / 8))
 146                 return 0;
 147
 148         return dr[index * 2 + 1];
 149 }
 150 EXPORT_SYMBOL_GPL(dcr_resource_len);
 151
 152 #ifdef CONFIG_PPC_DCR_MMIO
 153
 154 u64 of_translate_dcr_address(struct device_node *dev,
 155                              unsigned int dcr_n,
 156                              unsigned int *out_stride)
 157 {
 158         struct device_node *dp;
 159         const u32 *p;
 160         unsigned int stride;
 161         u64 ret = OF_BAD_ADDR;
 162
 163         dp = find_dcr_parent(dev);
 164         if (dp == NULL)
 165                 return OF_BAD_ADDR;
 166
 167         /* Stride is not properly defined yet, default to 0x10 for Axon */
 168         p = of_get_property(dp, "dcr-mmio-stride", NULL);
 169         stride = (p == NULL) ? 0x10 : *p;
 170
 171         /* XXX FIXME: Which property name is to use of the 2 following ? */
 172         p = of_get_property(dp, "dcr-mmio-range", NULL);
 173         if (p == NULL)
 174                 p = of_get_property(dp, "dcr-mmio-space", NULL);
 175         if (p == NULL)
 176                 goto done;
 177
 178         /* Maybe could do some better range checking here */
 179         ret = of_translate_address(dp, p);
 180         if (ret != OF_BAD_ADDR)
 181                 ret += (u64)(stride) * (u64)dcr_n;
 182         if (out_stride)
 183                 *out_stride = stride;
 184
 185  done:
 186         of_node_put(dp);
 187         return ret;
 188 }
 189
 190 dcr_host_mmio_t dcr_map_mmio(struct device_node *dev,
 191                              unsigned int dcr_n,
 192                              unsigned int dcr_c)
 193 {
 194         dcr_host_mmio_t ret = { .token = NULL, .stride = 0, .base = dcr_n };
 195         u64 addr;
 196
 197         pr_debug("dcr_map(%s, 0x%x, 0x%x)\n",
 198                  dev->full_name, dcr_n, dcr_c);
 199
 200         addr = of_translate_dcr_address(dev, dcr_n, &ret.stride);
 201         pr_debug("translates to addr: 0x%llx, stride: 0x%x\n",
 202                  (unsigned long long) addr, ret.stride);
 203         if (addr == OF_BAD_ADDR)
 204                 return ret;
 205         pr_debug("mapping 0x%x bytes\n", dcr_c * ret.stride);
 206         ret.token = ioremap(addr, dcr_c * ret.stride);
 207         if (ret.token == NULL)
 208                 return ret;
 209         pr_debug("mapped at 0x%p -> base is 0x%p\n",
 210                  ret.token, ret.token - dcr_n * ret.stride);
 211         ret.token -= dcr_n * ret.stride;
 212         return ret;
 213 }
 214 EXPORT_SYMBOL_GPL(dcr_map_mmio);
 215
 216 void dcr_unmap_mmio(dcr_host_mmio_t host, unsigned int dcr_c)
 217 {
 218         dcr_host_mmio_t h = host;
 219
 220         if (h.token == NULL)
 221                 return;
 222         h.token += host.base * h.stride;
 223         iounmap(h.token);
 224         h.token = NULL;
 225 }
 226 EXPORT_SYMBOL_GPL(dcr_unmap_mmio);
 227
 228 #endif /* defined(CONFIG_PPC_DCR_MMIO) */
 229
 230 #ifdef CONFIG_PPC_DCR_NATIVE
 231 DEFINE_SPINLOCK(dcr_ind_lock);
 232 #endif  /* defined(CONFIG_PPC_DCR_NATIVE) */
 233