kernel/drivers/video/fbdev/via/via_clock.c

   1 /*
   2  * Copyright 1998-2008 VIA Technologies, Inc. All Rights Reserved.
   3  * Copyright 2001-2008 S3 Graphics, Inc. All Rights Reserved.
   4  * Copyright 2011 Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public
   8  * License as published by the Free Software Foundation;
   9  * either version 2, or (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTIES OR REPRESENTATIONS; without even
  13  * the implied warranty of MERCHANTABILITY or FITNESS FOR
  14  * A PARTICULAR PURPOSE.See the GNU General Public License
  15  * for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc.,
  20  * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  21  */
  22 /*
  23  * clock and PLL management functions
  24  */
  25
  26 #include <linux/kernel.h>
  27 #include <linux/via-core.h>
  28 #include <asm/olpc.h>
  29 #include "via_clock.h"
  30 #include "global.h"
  31 #include "debug.h"
  32
  33 static const char *via_slap = "Please slap VIA Technologies to motivate them "
  34         "releasing full documentation for your platform!\n";
  35
  36 static inline u32 cle266_encode_pll(struct via_pll_config pll)
  37 {
  38         return (pll.multiplier << 8)
  39                 | (pll.rshift << 6)
  40                 | pll.divisor;
  41 }
  42
  43 static inline u32 k800_encode_pll(struct via_pll_config pll)
  44 {
  45         return ((pll.divisor - 2) << 16)
  46                 | (pll.rshift << 10)
  47                 | (pll.multiplier - 2);
  48 }
  49
  50 static inline u32 vx855_encode_pll(struct via_pll_config pll)
  51 {
  52         return (pll.divisor << 16)
  53                 | (pll.rshift << 10)
  54                 | pll.multiplier;
  55 }
  56
  57 static inline void cle266_set_primary_pll_encoded(u32 data)
  58 {
  59         via_write_reg_mask(VIASR, 0x40, 0x02, 0x02); /* enable reset */
  60         via_write_reg(VIASR, 0x46, data & 0xFF);
  61         via_write_reg(VIASR, 0x47, (data >> 8) & 0xFF);
  62         via_write_reg_mask(VIASR, 0x40, 0x00, 0x02); /* disable reset */
  63 }
  64
  65 static inline void k800_set_primary_pll_encoded(u32 data)
  66 {
  67         via_write_reg_mask(VIASR, 0x40, 0x02, 0x02); /* enable reset */
  68         via_write_reg(VIASR, 0x44, data & 0xFF);
  69         via_write_reg(VIASR, 0x45, (data >> 8) & 0xFF);
  70         via_write_reg(VIASR, 0x46, (data >> 16) & 0xFF);
  71         via_write_reg_mask(VIASR, 0x40, 0x00, 0x02); /* disable reset */
  72 }
  73
  74 static inline void cle266_set_secondary_pll_encoded(u32 data)
  75 {
  76         via_write_reg_mask(VIASR, 0x40, 0x04, 0x04); /* enable reset */
  77         via_write_reg(VIASR, 0x44, data & 0xFF);
  78         via_write_reg(VIASR, 0x45, (data >> 8) & 0xFF);
  79         via_write_reg_mask(VIASR, 0x40, 0x00, 0x04); /* disable reset */
  80 }
  81
  82 static inline void k800_set_secondary_pll_encoded(u32 data)
  83 {
  84         via_write_reg_mask(VIASR, 0x40, 0x04, 0x04); /* enable reset */
  85         via_write_reg(VIASR, 0x4A, data & 0xFF);
  86         via_write_reg(VIASR, 0x4B, (data >> 8) & 0xFF);
  87         via_write_reg(VIASR, 0x4C, (data >> 16) & 0xFF);
  88         via_write_reg_mask(VIASR, 0x40, 0x00, 0x04); /* disable reset */
  89 }
  90
  91 static inline void set_engine_pll_encoded(u32 data)
  92 {
  93         via_write_reg_mask(VIASR, 0x40, 0x01, 0x01); /* enable reset */
  94         via_write_reg(VIASR, 0x47, data & 0xFF);
  95         via_write_reg(VIASR, 0x48, (data >> 8) & 0xFF);
  96         via_write_reg(VIASR, 0x49, (data >> 16) & 0xFF);
  97         via_write_reg_mask(VIASR, 0x40, 0x00, 0x01); /* disable reset */
  98 }
  99
 100 static void cle266_set_primary_pll(struct via_pll_config config)
 101 {
 102         cle266_set_primary_pll_encoded(cle266_encode_pll(config));
 103 }
 104
 105 static void k800_set_primary_pll(struct via_pll_config config)
 106 {
 107         k800_set_primary_pll_encoded(k800_encode_pll(config));
 108 }
 109
 110 static void vx855_set_primary_pll(struct via_pll_config config)
 111 {
 112         k800_set_primary_pll_encoded(vx855_encode_pll(config));
 113 }
 114
 115 static void cle266_set_secondary_pll(struct via_pll_config config)
 116 {
 117         cle266_set_secondary_pll_encoded(cle266_encode_pll(config));
 118 }
 119
 120 static void k800_set_secondary_pll(struct via_pll_config config)
 121 {
 122         k800_set_secondary_pll_encoded(k800_encode_pll(config));
 123 }
 124
 125 static void vx855_set_secondary_pll(struct via_pll_config config)
 126 {
 127         k800_set_secondary_pll_encoded(vx855_encode_pll(config));
 128 }
 129
 130 static void k800_set_engine_pll(struct via_pll_config config)
 131 {
 132         set_engine_pll_encoded(k800_encode_pll(config));
 133 }
 134
 135 static void vx855_set_engine_pll(struct via_pll_config config)
 136 {
 137         set_engine_pll_encoded(vx855_encode_pll(config));
 138 }
 139
 140 static void set_primary_pll_state(u8 state)
 141 {
 142         u8 value;
 143
 144         switch (state) {
 145         case VIA_STATE_ON:
 146                 value = 0x20;
 147                 break;
 148         case VIA_STATE_OFF:
 149                 value = 0x00;
 150                 break;
 151         default:
 152                 return;
 153         }
 154
 155         via_write_reg_mask(VIASR, 0x2D, value, 0x30);
 156 }
 157
 158 static void set_secondary_pll_state(u8 state)
 159 {
 160         u8 value;
 161
 162         switch (state) {
 163         case VIA_STATE_ON:
 164                 value = 0x08;
 165                 break;
 166         case VIA_STATE_OFF:
 167                 value = 0x00;
 168                 break;
 169         default:
 170                 return;
 171         }
 172
 173         via_write_reg_mask(VIASR, 0x2D, value, 0x0C);
 174 }
 175
 176 static void set_engine_pll_state(u8 state)
 177 {
 178         u8 value;
 179
 180         switch (state) {
 181         case VIA_STATE_ON:
 182                 value = 0x02;
 183                 break;
 184         case VIA_STATE_OFF:
 185                 value = 0x00;
 186                 break;
 187         default:
 188                 return;
 189         }
 190
 191         via_write_reg_mask(VIASR, 0x2D, value, 0x03);
 192 }
 193
 194 static void set_primary_clock_state(u8 state)
 195 {
 196         u8 value;
 197
 198         switch (state) {
 199         case VIA_STATE_ON:
 200                 value = 0x20;
 201                 break;
 202         case VIA_STATE_OFF:
 203                 value = 0x00;
 204                 break;
 205         default:
 206                 return;
 207         }
 208
 209         via_write_reg_mask(VIASR, 0x1B, value, 0x30);
 210 }
 211
 212 static void set_secondary_clock_state(u8 state)
 213 {
 214         u8 value;
 215
 216         switch (state) {
 217         case VIA_STATE_ON:
 218                 value = 0x80;
 219                 break;
 220         case VIA_STATE_OFF:
 221                 value = 0x00;
 222                 break;
 223         default:
 224                 return;
 225         }
 226
 227         via_write_reg_mask(VIASR, 0x1B, value, 0xC0);
 228 }
 229
 230 static inline u8 set_clock_source_common(enum via_clksrc source, bool use_pll)
 231 {
 232         u8 data = 0;
 233
 234         switch (source) {
 235         case VIA_CLKSRC_X1:
 236                 data = 0x00;
 237                 break;
 238         case VIA_CLKSRC_TVX1:
 239                 data = 0x02;
 240                 break;
 241         case VIA_CLKSRC_TVPLL:
 242                 data = 0x04; /* 0x06 should be the same */
 243                 break;
 244         case VIA_CLKSRC_DVP1TVCLKR:
 245                 data = 0x0A;
 246                 break;
 247         case VIA_CLKSRC_CAP0:
 248                 data = 0xC;
 249                 break;
 250         case VIA_CLKSRC_CAP1:
 251                 data = 0x0E;
 252                 break;
 253         }
 254
 255         if (!use_pll)
 256                 data |= 1;
 257
 258         return data;
 259 }
 260
 261 static void set_primary_clock_source(enum via_clksrc source, bool use_pll)
 262 {
 263         u8 data = set_clock_source_common(source, use_pll) << 4;
 264         via_write_reg_mask(VIACR, 0x6C, data, 0xF0);
 265 }
 266
 267 static void set_secondary_clock_source(enum via_clksrc source, bool use_pll)
 268 {
 269         u8 data = set_clock_source_common(source, use_pll);
 270         via_write_reg_mask(VIACR, 0x6C, data, 0x0F);
 271 }
 272
 273 static void dummy_set_clock_state(u8 state)
 274 {
 275         printk(KERN_INFO "Using undocumented set clock state.\n%s", via_slap);
 276 }
 277
 278 static void dummy_set_clock_source(enum via_clksrc source, bool use_pll)
 279 {
 280         printk(KERN_INFO "Using undocumented set clock source.\n%s", via_slap);
 281 }
 282
 283 static void dummy_set_pll_state(u8 state)
 284 {
 285         printk(KERN_INFO "Using undocumented set PLL state.\n%s", via_slap);
 286 }
 287
 288 static void dummy_set_pll(struct via_pll_config config)
 289 {
 290         printk(KERN_INFO "Using undocumented set PLL.\n%s", via_slap);
 291 }
 292
 293 static void noop_set_clock_state(u8 state)
 294 {
 295 }
 296
 297 void via_clock_init(struct via_clock *clock, int gfx_chip)
 298 {
 299         switch (gfx_chip) {
 300         case UNICHROME_CLE266:
 301         case UNICHROME_K400:
 302                 clock->set_primary_clock_state = dummy_set_clock_state;
 303                 clock->set_primary_clock_source = dummy_set_clock_source;
 304                 clock->set_primary_pll_state = dummy_set_pll_state;
 305                 clock->set_primary_pll = cle266_set_primary_pll;
 306
 307                 clock->set_secondary_clock_state = dummy_set_clock_state;
 308                 clock->set_secondary_clock_source = dummy_set_clock_source;
 309                 clock->set_secondary_pll_state = dummy_set_pll_state;
 310                 clock->set_secondary_pll = cle266_set_secondary_pll;
 311
 312                 clock->set_engine_pll_state = dummy_set_pll_state;
 313                 clock->set_engine_pll = dummy_set_pll;
 314                 break;
 315         case UNICHROME_K800:
 316         case UNICHROME_PM800:
 317         case UNICHROME_CN700:
 318         case UNICHROME_CX700:
 319         case UNICHROME_CN750:
 320         case UNICHROME_K8M890:
 321         case UNICHROME_P4M890:
 322         case UNICHROME_P4M900:
 323         case UNICHROME_VX800:
 324                 clock->set_primary_clock_state = set_primary_clock_state;
 325                 clock->set_primary_clock_source = set_primary_clock_source;
 326                 clock->set_primary_pll_state = set_primary_pll_state;
 327                 clock->set_primary_pll = k800_set_primary_pll;
 328
 329                 clock->set_secondary_clock_state = set_secondary_clock_state;
 330                 clock->set_secondary_clock_source = set_secondary_clock_source;
 331                 clock->set_secondary_pll_state = set_secondary_pll_state;
 332                 clock->set_secondary_pll = k800_set_secondary_pll;
 333
 334                 clock->set_engine_pll_state = set_engine_pll_state;
 335                 clock->set_engine_pll = k800_set_engine_pll;
 336                 break;
 337         case UNICHROME_VX855:
 338         case UNICHROME_VX900:
 339                 clock->set_primary_clock_state = set_primary_clock_state;
 340                 clock->set_primary_clock_source = set_primary_clock_source;
 341                 clock->set_primary_pll_state = set_primary_pll_state;
 342                 clock->set_primary_pll = vx855_set_primary_pll;
 343
 344                 clock->set_secondary_clock_state = set_secondary_clock_state;
 345                 clock->set_secondary_clock_source = set_secondary_clock_source;
 346                 clock->set_secondary_pll_state = set_secondary_pll_state;
 347                 clock->set_secondary_pll = vx855_set_secondary_pll;
 348
 349                 clock->set_engine_pll_state = set_engine_pll_state;
 350                 clock->set_engine_pll = vx855_set_engine_pll;
 351                 break;
 352
 353         }
 354
 355         if (machine_is_olpc()) {
 356                 /* The OLPC XO-1.5 cannot suspend/resume reliably if the
 357                  * IGA1/IGA2 clocks are set as on or off (memory rot
 358                  * occasionally happens during suspend under such
 359                  * configurations).
 360                  *
 361                  * The only known stable scenario is to leave this bits as-is,
 362                  * which in their default states are documented to enable the
 363                  * clock only when it is needed.
 364                  */
 365                 clock->set_primary_clock_state = noop_set_clock_state;
 366                 clock->set_secondary_clock_state = noop_set_clock_state;
 367         }
 368 }