arch/powerpc/cpu/mpc86xx/speed.c

   1 /*
   2  * Copyright 2004 Freescale Semiconductor.
   3  * Jeff Brown
   4  * Srikanth Srinivasan (srikanth.srinivasan@freescale.com)
   5  *
   6  * (C) Copyright 2000-2002
   7  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
   8  *
   9  * SPDX-License-Identifier:     GPL-2.0+
  10  */
  11
  12 #include <common.h>
  13 #include <mpc86xx.h>
  14 #include <asm/processor.h>
  15 #include <asm/io.h>
  16
  17 DECLARE_GLOBAL_DATA_PTR;
  18
  19 /* used in some defintiions of CONFIG_SYS_CLK_FREQ */
  20 extern unsigned long get_board_sys_clk(unsigned long dummy);
  21
  22 void get_sys_info(sys_info_t *sys_info)
  23 {
  24         volatile immap_t *immap = (immap_t *) CONFIG_SYS_IMMR;
  25         volatile ccsr_gur_t *gur = &immap->im_gur;
  26         uint plat_ratio, e600_ratio;
  27
  28         plat_ratio = (gur->porpllsr) & 0x0000003e;
  29         plat_ratio >>= 1;
  30
  31         switch (plat_ratio) {
  32         case 0x0:
  33                 sys_info->freq_systembus = 16 * CONFIG_SYS_CLK_FREQ;
  34                 break;
  35         case 0x02:
  36         case 0x03:
  37         case 0x04:
  38         case 0x05:
  39         case 0x06:
  40         case 0x08:
  41         case 0x09:
  42         case 0x0a:
  43         case 0x0c:
  44         case 0x10:
  45                 sys_info->freq_systembus = plat_ratio * CONFIG_SYS_CLK_FREQ;
  46                 break;
  47         default:
  48                 sys_info->freq_systembus = 0;
  49                 break;
  50         }
  51
  52         e600_ratio = (gur->porpllsr) & 0x003f0000;
  53         e600_ratio >>= 16;
  54
  55         switch (e600_ratio) {
  56         case 0x10:
  57                 sys_info->freq_processor = 2 * sys_info->freq_systembus;
  58                 break;
  59         case 0x19:
  60                 sys_info->freq_processor = 5 * sys_info->freq_systembus / 2;
  61                 break;
  62         case 0x20:
  63                 sys_info->freq_processor = 3 * sys_info->freq_systembus;
  64                 break;
  65         case 0x39:
  66                 sys_info->freq_processor = 7 * sys_info->freq_systembus / 2;
  67                 break;
  68         case 0x28:
  69                 sys_info->freq_processor = 4 * sys_info->freq_systembus;
  70                 break;
  71         case 0x1d:
  72                 sys_info->freq_processor = 9 * sys_info->freq_systembus / 2;
  73                 break;
  74         default:
  75                 sys_info->freq_processor = e600_ratio +
  76                                                 sys_info->freq_systembus;
  77                 break;
  78         }
  79
  80         sys_info->freq_localbus = sys_info->freq_systembus;
  81 }
  82
  83
  84 /*
  85  * Measure CPU clock speed (core clock GCLK1, GCLK2)
  86  * (Approx. GCLK frequency in Hz)
  87  */
  88
  89 int get_clocks(void)
  90 {
  91         sys_info_t sys_info;
  92
  93         get_sys_info(&sys_info);
  94         gd->cpu_clk = sys_info.freq_processor;
  95         gd->bus_clk = sys_info.freq_systembus;
  96         gd->arch.lbc_clk = sys_info.freq_localbus;
  97
  98         /*
  99          * The base clock for I2C depends on the actual SOC.  Unfortunately,
 100          * there is no pattern that can be used to determine the frequency, so
 101          * the only choice is to look up the actual SOC number and use the value
 102          * for that SOC. This information is taken from application note
 103          * AN2919.
 104          */
 105 #ifdef CONFIG_ARCH_MPC8610
 106         gd->arch.i2c1_clk = sys_info.freq_systembus;
 107 #else
 108         gd->arch.i2c1_clk = sys_info.freq_systembus / 2;
 109 #endif
 110         gd->arch.i2c2_clk = gd->arch.i2c1_clk;
 111
 112         if (gd->cpu_clk != 0)
 113                 return 0;
 114         else
 115                 return 1;
 116 }
 117
 118
 119 /*
 120  * get_bus_freq
 121  *      Return system bus freq in Hz
 122  */
 123
 124 ulong get_bus_freq(ulong dummy)
 125 {
 126         ulong val;
 127         sys_info_t sys_info;
 128
 129         get_sys_info(&sys_info);
 130         val = sys_info.freq_systembus;
 131
 132         return val;
 133 }