cpu/mpc5xxx/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 <mpc5xxx.h>
  26 #include <asm/processor.h>
  27
  28 /* ------------------------------------------------------------------------- */
  29
  30 /* Bus-to-Core Multipliers */
  31
  32 static int bus2core[] = {
  33         0,  0,  0,  10, 20, 20, 25, 45,
  34         30, 55, 40, 50, 0,  60, 35, 0,
  35         30, 25, 65, 10, 70, 20, 75, 45,
  36         0,  55, 40, 50, 80, 60, 35, 0
  37 };
  38 /* ------------------------------------------------------------------------- */
  39
  40 /*
  41  *
  42  */
  43
  44 int get_clocks (void)
  45 {
  46         DECLARE_GLOBAL_DATA_PTR;
  47
  48         ulong val, vco;
  49
  50 #if !defined(CFG_MPC5XXX_CLKIN)
  51 #error clock measuring not implemented yet - define CFG_MPC5XXX_CLKIN
  52 #endif
  53
  54         val = *(vu_long *)MPC5XXX_CDM_PORCFG;
  55         if (val & (1 << 6)) {
  56                 vco = CFG_MPC5XXX_CLKIN * 12;
  57         } else {
  58                 vco = CFG_MPC5XXX_CLKIN * 16;
  59         }
  60         if (val & (1 << 5)) {
  61                 gd->bus_clk = vco / 8;
  62         } else {
  63                 gd->bus_clk = vco / 4;
  64         }
  65         gd->cpu_clk = gd->bus_clk * bus2core[val & 0x1f] / 10;
  66
  67         val = *(vu_long *)MPC5XXX_CDM_CFG;
  68         if (val & (1 << 8)) {
  69                 gd->ipb_clk = gd->bus_clk / 2;
  70         } else {
  71                 gd->ipb_clk = gd->bus_clk;
  72         }
  73         switch (val & 3) {
  74                 case 0: gd->pci_clk = gd->ipb_clk; break;
  75                 case 1: gd->pci_clk = gd->ipb_clk / 2; break;
  76                 default: gd->pci_clk = gd->bus_clk / 4; break;
  77         }
  78
  79         return (0);
  80 }
  81
  82 int prt_mpc5xxx_clks (void)
  83 {
  84         DECLARE_GLOBAL_DATA_PTR;
  85
  86         printf("       Bus %ld MHz, IPB %ld MHz, PCI %ld MHz\n",
  87                         gd->bus_clk / 1000000, gd->ipb_clk / 1000000,
  88                         gd->pci_clk / 1000000);
  89
  90         return (0);
  91 }
  92
  93 /* ------------------------------------------------------------------------- */