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         uint lcrr_div;
  28
  29         plat_ratio = (gur->porpllsr) & 0x0000003e;
  30         plat_ratio >>= 1;
  31
  32         switch (plat_ratio) {
  33         case 0x0:
  34                 sys_info->freq_systembus = 16 * CONFIG_SYS_CLK_FREQ;
  35                 break;
  36         case 0x02:
  37         case 0x03:
  38         case 0x04:
  39         case 0x05:
  40         case 0x06:
  41         case 0x08:
  42         case 0x09:
  43         case 0x0a:
  44         case 0x0c:
  45         case 0x10:
  46                 sys_info->freq_systembus = plat_ratio * CONFIG_SYS_CLK_FREQ;
  47                 break;
  48         default:
  49                 sys_info->freq_systembus = 0;
  50                 break;
  51         }
  52
  53         e600_ratio = (gur->porpllsr) & 0x003f0000;
  54         e600_ratio >>= 16;
  55
  56         switch (e600_ratio) {
  57         case 0x10:
  58                 sys_info->freq_processor = 2 * sys_info->freq_systembus;
  59                 break;
  60         case 0x19:
  61                 sys_info->freq_processor = 5 * sys_info->freq_systembus / 2;
  62                 break;
  63         case 0x20:
  64                 sys_info->freq_processor = 3 * sys_info->freq_systembus;
  65                 break;
  66         case 0x39:
  67                 sys_info->freq_processor = 7 * sys_info->freq_systembus / 2;
  68                 break;
  69         case 0x28:
  70                 sys_info->freq_processor = 4 * sys_info->freq_systembus;
  71                 break;
  72         case 0x1d:
  73                 sys_info->freq_processor = 9 * sys_info->freq_systembus / 2;
  74                 break;
  75         default:
  76                 sys_info->freq_processor = e600_ratio +
  77                                                 sys_info->freq_systembus;
  78                 break;
  79         }
  80
  81 #if defined(CONFIG_SYS_LBC_LCRR)
  82         /* We will program LCRR to this value later */
  83         lcrr_div = CONFIG_SYS_LBC_LCRR & LCRR_CLKDIV;
  84 #else
  85         lcrr_div = in_be32(&immap->im_lbc.lcrr) & LCRR_CLKDIV;
  86 #endif
  87         if (lcrr_div == 2 || lcrr_div == 4 || lcrr_div == 8) {
  88                 sys_info->freq_localbus = sys_info->freq_systembus
  89                                                         / (lcrr_div * 2);
  90         } else {
  91                 /* In case anyone cares what the unknown value is */
  92                 sys_info->freq_localbus = lcrr_div;
  93         }
  94 }
  95
  96
  97 /*
  98  * Measure CPU clock speed (core clock GCLK1, GCLK2)
  99  * (Approx. GCLK frequency in Hz)
 100  */
 101
 102 int get_clocks(void)
 103 {
 104         sys_info_t sys_info;
 105
 106         get_sys_info(&sys_info);
 107         gd->cpu_clk = sys_info.freq_processor;
 108         gd->bus_clk = sys_info.freq_systembus;
 109         gd->arch.lbc_clk = sys_info.freq_localbus;
 110
 111         /*
 112          * The base clock for I2C depends on the actual SOC.  Unfortunately,
 113          * there is no pattern that can be used to determine the frequency, so
 114          * the only choice is to look up the actual SOC number and use the value
 115          * for that SOC. This information is taken from application note
 116          * AN2919.
 117          */
 118 #ifdef CONFIG_MPC8610
 119         gd->arch.i2c1_clk = sys_info.freq_systembus;
 120 #else
 121         gd->arch.i2c1_clk = sys_info.freq_systembus / 2;
 122 #endif
 123         gd->arch.i2c2_clk = gd->arch.i2c1_clk;
 124
 125         if (gd->cpu_clk != 0)
 126                 return 0;
 127         else
 128                 return 1;
 129 }
 130
 131
 132 /*
 133  * get_bus_freq
 134  *      Return system bus freq in Hz
 135  */
 136
 137 ulong get_bus_freq(ulong dummy)
 138 {
 139         ulong val;
 140         sys_info_t sys_info;
 141
 142         get_sys_info(&sys_info);
 143         val = sys_info.freq_systembus;
 144
 145         return val;
 146 }