drivers/gpu/drm/nouveau/nouveau_volt.c

   1 /*
   2  * Copyright 2010 Red Hat Inc.
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice shall be included in
  12  * all copies or substantial portions of the Software.
  13  *
  14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  17  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
  18  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  19  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  20  * OTHER DEALINGS IN THE SOFTWARE.
  21  *
  22  * Authors: Ben Skeggs
  23  */
  24
  25 #include "drmP.h"
  26
  27 #include "nouveau_drv.h"
  28 #include "nouveau_pm.h"
  29
  30 static const enum dcb_gpio_tag vidtag[] = { 0x04, 0x05, 0x06, 0x1a };
  31 static int nr_vidtag = sizeof(vidtag) / sizeof(vidtag[0]);
  32
  33 int
  34 nouveau_voltage_gpio_get(struct drm_device *dev)
  35 {
  36         struct drm_nouveau_private *dev_priv = dev->dev_private;
  37         struct nouveau_gpio_engine *gpio = &dev_priv->engine.gpio;
  38         struct nouveau_pm_voltage *volt = &dev_priv->engine.pm.voltage;
  39         u8 vid = 0;
  40         int i;
  41
  42         for (i = 0; i < nr_vidtag; i++) {
  43                 if (!(volt->vid_mask & (1 << i)))
  44                         continue;
  45
  46                 vid |= gpio->get(dev, vidtag[i]) << i;
  47         }
  48
  49         return nouveau_volt_lvl_lookup(dev, vid);
  50 }
  51
  52 int
  53 nouveau_voltage_gpio_set(struct drm_device *dev, int voltage)
  54 {
  55         struct drm_nouveau_private *dev_priv = dev->dev_private;
  56         struct nouveau_gpio_engine *gpio = &dev_priv->engine.gpio;
  57         struct nouveau_pm_voltage *volt = &dev_priv->engine.pm.voltage;
  58         int vid, i;
  59
  60         vid = nouveau_volt_vid_lookup(dev, voltage);
  61         if (vid < 0)
  62                 return vid;
  63
  64         for (i = 0; i < nr_vidtag; i++) {
  65                 if (!(volt->vid_mask & (1 << i)))
  66                         continue;
  67
  68                 gpio->set(dev, vidtag[i], !!(vid & (1 << i)));
  69         }
  70
  71         return 0;
  72 }
  73
  74 int
  75 nouveau_volt_vid_lookup(struct drm_device *dev, int voltage)
  76 {
  77         struct drm_nouveau_private *dev_priv = dev->dev_private;
  78         struct nouveau_pm_voltage *volt = &dev_priv->engine.pm.voltage;
  79         int i;
  80
  81         for (i = 0; i < volt->nr_level; i++) {
  82                 if (volt->level[i].voltage == voltage)
  83                         return volt->level[i].vid;
  84         }
  85
  86         return -ENOENT;
  87 }
  88
  89 int
  90 nouveau_volt_lvl_lookup(struct drm_device *dev, int vid)
  91 {
  92         struct drm_nouveau_private *dev_priv = dev->dev_private;
  93         struct nouveau_pm_voltage *volt = &dev_priv->engine.pm.voltage;
  94         int i;
  95
  96         for (i = 0; i < volt->nr_level; i++) {
  97                 if (volt->level[i].vid == vid)
  98                         return volt->level[i].voltage;
  99         }
 100
 101         return -ENOENT;
 102 }
 103
 104 void
 105 nouveau_volt_init(struct drm_device *dev)
 106 {
 107         struct drm_nouveau_private *dev_priv = dev->dev_private;
 108         struct nouveau_pm_engine *pm = &dev_priv->engine.pm;
 109         struct nouveau_pm_voltage *voltage = &pm->voltage;
 110         struct nvbios *bios = &dev_priv->vbios;
 111         struct bit_entry P;
 112         u8 *volt = NULL, *entry;
 113         int i, headerlen, recordlen, entries, vidmask, vidshift;
 114
 115         if (bios->type == NVBIOS_BIT) {
 116                 if (bit_table(dev, 'P', &P))
 117                         return;
 118
 119                 if (P.version == 1)
 120                         volt = ROMPTR(bios, P.data[16]);
 121                 else
 122                 if (P.version == 2)
 123                         volt = ROMPTR(bios, P.data[12]);
 124                 else {
 125                         NV_WARN(dev, "unknown volt for BIT P %d\n", P.version);
 126                 }
 127         } else {
 128                 if (bios->data[bios->offset + 6] < 0x27) {
 129                         NV_DEBUG(dev, "BMP version too old for voltage\n");
 130                         return;
 131                 }
 132
 133                 volt = ROMPTR(bios, bios->data[bios->offset + 0x98]);
 134         }
 135
 136         if (!volt) {
 137                 NV_DEBUG(dev, "voltage table pointer invalid\n");
 138                 return;
 139         }
 140
 141         switch (volt[0]) {
 142         case 0x10:
 143         case 0x11:
 144         case 0x12:
 145                 headerlen = 5;
 146                 recordlen = volt[1];
 147                 entries   = volt[2];
 148                 vidshift  = 0;
 149                 vidmask   = volt[4];
 150                 break;
 151         case 0x20:
 152                 headerlen = volt[1];
 153                 recordlen = volt[3];
 154                 entries   = volt[2];
 155                 vidshift  = 0; /* could be vidshift like 0x30? */
 156                 vidmask   = volt[5];
 157                 break;
 158         case 0x30:
 159                 headerlen = volt[1];
 160                 recordlen = volt[2];
 161                 entries   = volt[3];
 162                 vidmask   = volt[4];
 163                 /* no longer certain what volt[5] is, if it's related to
 164                  * the vid shift then it's definitely not a function of
 165                  * how many bits are set.
 166                  *
 167                  * after looking at a number of nva3+ vbios images, they
 168                  * all seem likely to have a static shift of 2.. lets
 169                  * go with that for now until proven otherwise.
 170                  */
 171                 vidshift  = 2;
 172                 break;
 173         default:
 174                 NV_WARN(dev, "voltage table 0x%02x unknown\n", volt[0]);
 175                 return;
 176         }
 177
 178         /* validate vid mask */
 179         voltage->vid_mask = vidmask;
 180         if (!voltage->vid_mask)
 181                 return;
 182
 183         i = 0;
 184         while (vidmask) {
 185                 if (i > nr_vidtag) {
 186                         NV_DEBUG(dev, "vid bit %d unknown\n", i);
 187                         return;
 188                 }
 189
 190                 if (!nouveau_bios_gpio_entry(dev, vidtag[i])) {
 191                         NV_DEBUG(dev, "vid bit %d has no gpio tag\n", i);
 192                         return;
 193                 }
 194
 195                 vidmask >>= 1;
 196                 i++;
 197         }
 198
 199         /* parse vbios entries into common format */
 200         voltage->level = kcalloc(entries, sizeof(*voltage->level), GFP_KERNEL);
 201         if (!voltage->level)
 202                 return;
 203
 204         entry = volt + headerlen;
 205         for (i = 0; i < entries; i++, entry += recordlen) {
 206                 voltage->level[i].voltage = entry[0];
 207                 voltage->level[i].vid     = entry[1] >> vidshift;
 208         }
 209         voltage->nr_level  = entries;
 210         voltage->supported = true;
 211 }
 212
 213 void
 214 nouveau_volt_fini(struct drm_device *dev)
 215 {
 216         struct drm_nouveau_private *dev_priv = dev->dev_private;
 217         struct nouveau_pm_voltage *volt = &dev_priv->engine.pm.voltage;
 218
 219         kfree(volt->level);
 220 }