arch/powerpc/cpu/74xx_7xx/speed.c

   1 /*
   2  * (C) Copyright 2000-2002
   3  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
   4  *
   5  * See file CREDITS for list of people who contributed to this
   6  * project.
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License as
  10  * published by the Free Software Foundation; either version 2 of
  11  * the License, or (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  21  * MA 02111-1307 USA
  22  */
  23
  24 #include <common.h>
  25 #include <74xx_7xx.h>
  26 #include <asm/processor.h>
  27
  28 #ifdef CONFIG_AMIGAONEG3SE
  29 #include "../board/MAI/AmigaOneG3SE/via686.h"
  30 #endif
  31
  32 DECLARE_GLOBAL_DATA_PTR;
  33
  34 extern unsigned long get_board_bus_clk (void);
  35
  36 static const int hid1_multipliers_x_10[] = {
  37         25,     /* 0000 - 2.5x */
  38         75,     /* 0001 - 7.5x */
  39         70,     /* 0010 - 7x */
  40         10,     /* 0011 - bypass */
  41         20,     /* 0100 - 2x */
  42         65,     /* 0101 - 6.5x */
  43         100,    /* 0110 - 10x */
  44         45,     /* 0111 - 4.5x */
  45         30,     /* 1000 - 3x */
  46         55,     /* 1001 - 5.5x */
  47         40,     /* 1010 - 4x */
  48         50,     /* 1011 - 5x */
  49         80,     /* 1100 - 8x */
  50         60,     /* 1101 - 6x */
  51         35,     /* 1110 - 3.5x */
  52         0       /* 1111 - off */
  53 };
  54
  55 /* PLL_CFG[0:4] table for cpu 7448/7447A/7455/7457 */
  56 static const int hid1_74xx_multipliers_x_10[] = {
  57         115,    /* 00000 - 11.5x  */
  58         170,    /* 00001 - 17x    */
  59         75,     /* 00010 -  7.5x  */
  60         150,    /* 00011 - 15x    */
  61         70,     /* 00100 -  7x    */
  62         180,    /* 00101 - 18x    */
  63         10,     /* 00110 - bypass */
  64         200,    /* 00111 - 20x    */
  65         20,     /* 01000 -  2x    */
  66         210,    /* 01001 - 21x    */
  67         65,     /* 01010 -  6.5x  */
  68         130,    /* 01011 - 13x    */
  69         85,     /* 01100 -  8.5x  */
  70         240,    /* 01101 - 24x    */
  71         95,     /* 01110 -  9.5x  */
  72         90,     /* 01111 -  9x    */
  73         30,     /* 10000 -  3x    */
  74         105,    /* 10001 - 10.5x  */
  75         55,     /* 10010 -  5.5x  */
  76         110,    /* 10011 - 11x    */
  77         40,     /* 10100 -  4x    */
  78         100,    /* 10101 - 10x    */
  79         50,     /* 10110 -  5x    */
  80         120,    /* 10111 - 12x    */
  81         80,     /* 11000 -  8x    */
  82         140,    /* 11001 - 14x    */
  83         60,     /* 11010 -  6x    */
  84         160,    /* 11011 - 16x    */
  85         135,    /* 11100 - 13.5x  */
  86         280,    /* 11101 - 28x    */
  87         0,      /* 11110 - off    */
  88         125     /* 11111 - 12.5x  */
  89 };
  90
  91 static const int hid1_fx_multipliers_x_10[] = {
  92         00,     /* 0000 - off */
  93         00,     /* 0001 - off */
  94         10,     /* 0010 - bypass */
  95         10,     /* 0011 - bypass */
  96         20,     /* 0100 - 2x */
  97         25,     /* 0101 - 2.5x */
  98         30,     /* 0110 - 3x */
  99         35,     /* 0111 - 3.5x */
 100         40,     /* 1000 - 4x */
 101         45,     /* 1001 - 4.5x */
 102         50,     /* 1010 - 5x */
 103         55,     /* 1011 - 5.5x */
 104         60,     /* 1100 - 6x */
 105         65,     /* 1101 - 6.5x */
 106         70,     /* 1110 - 7x */
 107         75,     /* 1111 - 7.5 */
 108         80,     /* 10000 - 8x */
 109         85,     /* 10001 - 8.5x */
 110         90,     /* 10010 - 9x */
 111         95,     /* 10011 - 9.5x */
 112         100,    /* 10100 - 10x */
 113         110,    /* 10101 - 11x */
 114         120,    /* 10110 - 12x */
 115 };
 116
 117
 118 /* ------------------------------------------------------------------------- */
 119
 120 /*
 121  * Measure CPU clock speed (core clock GCLK1, GCLK2)
 122  *
 123  * (Approx. GCLK frequency in Hz)
 124  */
 125
 126 int get_clocks (void)
 127 {
 128         ulong clock = 0;
 129
 130 #ifdef CONFIG_SYS_BUS_CLK
 131         gd->bus_clk = CONFIG_SYS_BUS_CLK;       /* bus clock is a fixed frequency */
 132 #else
 133         gd->bus_clk = get_board_bus_clk ();     /* bus clock is configurable */
 134 #endif
 135
 136         /* calculate the clock frequency based upon the CPU type */
 137         switch (get_cpu_type()) {
 138         case CPU_7447A:
 139         case CPU_7448:
 140         case CPU_7455:
 141         case CPU_7457:
 142                 /*
 143                  * Make sure division is done before multiplication to prevent 32-bit
 144                  * arithmetic overflows which will cause a negative number
 145                  */
 146                 clock = (gd->bus_clk / 10) *
 147                         hid1_74xx_multipliers_x_10[(get_hid1 () >> 12) & 0x1F];
 148                 break;
 149
 150         case CPU_750GX:
 151         case CPU_750FX:
 152                 clock = (gd->bus_clk / 10) *
 153                         hid1_fx_multipliers_x_10[get_hid1 () >> 27];
 154                 break;
 155
 156         case CPU_7450:
 157         case CPU_740:
 158         case CPU_740P:
 159         case CPU_745:
 160         case CPU_750CX:
 161         case CPU_750:
 162         case CPU_750P:
 163         case CPU_755:
 164         case CPU_7400:
 165         case CPU_7410:
 166                 /*
 167                  * Make sure division is done before multiplication to prevent 32-bit
 168                  * arithmetic overflows which will cause a negative number
 169                  */
 170                 clock = (gd->bus_clk / 10) *
 171                         hid1_multipliers_x_10[get_hid1 () >> 28];
 172                 break;
 173
 174         case CPU_UNKNOWN:
 175                printf ("get_gclk_freq(): unknown CPU type\n");
 176                clock = 0;
 177                return (1);
 178         }
 179
 180         gd->cpu_clk = clock;
 181
 182         return (0);
 183 }
 184
 185 /* ------------------------------------------------------------------------- */