cpu/mpc85xx/speed.c

   1 /*
   2  * Copyright 2004 Freescale Semiconductor.
   3  * (C) Copyright 2003 Motorola Inc.
   4  * Xianghua Xiao, (X.Xiao@motorola.com)
   5  *
   6  * (C) Copyright 2000
   7  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
   8  *
   9  * See file CREDITS for list of people who contributed to this
  10  * project.
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License as
  14  * published by the Free Software Foundation; either version 2 of
  15  * the License, or (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with this program; if not, write to the Free Software
  24  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  25  * MA 02111-1307 USA
  26  */
  27
  28 #include <common.h>
  29 #include <ppc_asm.tmpl>
  30 #include <asm/processor.h>
  31
  32 DECLARE_GLOBAL_DATA_PTR;
  33
  34 /* --------------------------------------------------------------- */
  35
  36 void get_sys_info (sys_info_t * sysInfo)
  37 {
  38         volatile immap_t    *immap = (immap_t *)CFG_IMMR;
  39         volatile ccsr_gur_t *gur = &immap->im_gur;
  40         uint plat_ratio,e500_ratio;
  41
  42         plat_ratio = (gur->porpllsr) & 0x0000003e;
  43         plat_ratio >>= 1;
  44         switch(plat_ratio) {
  45         case 0x02:
  46         case 0x03:
  47         case 0x04:
  48         case 0x05:
  49         case 0x06:
  50         case 0x08:
  51         case 0x09:
  52         case 0x0a:
  53         case 0x0c:
  54         case 0x10:
  55                 sysInfo->freqSystemBus = plat_ratio * CONFIG_SYS_CLK_FREQ;
  56                 break;
  57         default:
  58                 sysInfo->freqSystemBus = 0;
  59                 break;
  60         }
  61
  62         e500_ratio = (gur->porpllsr) & 0x003f0000;
  63         e500_ratio >>= 16;
  64         switch(e500_ratio) {
  65         case 0x04:
  66                 sysInfo->freqProcessor = 2*sysInfo->freqSystemBus;
  67                 break;
  68         case 0x05:
  69                 sysInfo->freqProcessor = 5*sysInfo->freqSystemBus/2;
  70                 break;
  71         case 0x06:
  72                 sysInfo->freqProcessor = 3*sysInfo->freqSystemBus;
  73                 break;
  74         case 0x07:
  75                 sysInfo->freqProcessor = 7*sysInfo->freqSystemBus/2;
  76                 break;
  77         default:
  78                 sysInfo->freqProcessor = 0;
  79                 break;
  80         }
  81 }
  82
  83 int get_clocks (void)
  84 {
  85         sys_info_t sys_info;
  86 #if defined(CONFIG_CPM2)
  87         volatile immap_t *immap = (immap_t *) CFG_IMMR;
  88         uint sccr, dfbrg;
  89
  90         /* set VCO = 4 * BRG */
  91         immap->im_cpm.im_cpm_intctl.sccr &= 0xfffffffc;
  92         sccr = immap->im_cpm.im_cpm_intctl.sccr;
  93         dfbrg = (sccr & SCCR_DFBRG_MSK) >> SCCR_DFBRG_SHIFT;
  94 #endif
  95         get_sys_info (&sys_info);
  96         gd->cpu_clk = sys_info.freqProcessor;
  97         gd->bus_clk = sys_info.freqSystemBus;
  98 #if defined(CONFIG_CPM2)
  99         gd->vco_out = 2*sys_info.freqSystemBus;
 100         gd->cpm_clk = gd->vco_out / 2;
 101         gd->scc_clk = gd->vco_out / 4;
 102         gd->brg_clk = gd->vco_out / (1 << (2 * (dfbrg + 1)));
 103 #endif
 104
 105         if(gd->cpu_clk != 0) return (0);
 106         else return (1);
 107 }
 108
 109
 110 /********************************************
 111  * get_bus_freq
 112  * return system bus freq in Hz
 113  *********************************************/
 114 ulong get_bus_freq (ulong dummy)
 115 {
 116         ulong val;
 117
 118         sys_info_t sys_info;
 119
 120         get_sys_info (&sys_info);
 121         val = sys_info.freqSystemBus;
 122
 123         return val;
 124 }