git.sur5r.net Git - u-boot/blob - arch/powerpc/cpu/mpc86xx/speed.c

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