arch/sh/boards/overdrive/time.c

   1 /*
   2  * arch/sh/boards/overdrive/time.c
   3  *
   4  * Copyright (C) 2000 Stuart Menefy (stuart.menefy@st.com)
   5  * Copyright (C) 2002 Paul Mundt (lethal@chaoticdreams.org)
   6  *
   7  * May be copied or modified under the terms of the GNU General Public
   8  * License.  See linux/COPYING for more information.
   9  *
  10  * STMicroelectronics Overdrive Support.
  11  */
  12
  13 void od_time_init(void)
  14 {
  15         struct frqcr_data {
  16                 unsigned short frqcr;
  17                 struct {
  18                         unsigned char multiplier;
  19                         unsigned char divisor;
  20                 } factor[3];
  21         };
  22
  23         static struct frqcr_data st40_frqcr_table[] = {
  24                 { 0x000, {{1,1}, {1,1}, {1,2}}},
  25                 { 0x002, {{1,1}, {1,1}, {1,4}}},
  26                 { 0x004, {{1,1}, {1,1}, {1,8}}},
  27                 { 0x008, {{1,1}, {1,2}, {1,2}}},
  28                 { 0x00A, {{1,1}, {1,2}, {1,4}}},
  29                 { 0x00C, {{1,1}, {1,2}, {1,8}}},
  30                 { 0x011, {{1,1}, {2,3}, {1,6}}},
  31                 { 0x013, {{1,1}, {2,3}, {1,3}}},
  32                 { 0x01A, {{1,1}, {1,2}, {1,4}}},
  33                 { 0x01C, {{1,1}, {1,2}, {1,8}}},
  34                 { 0x023, {{1,1}, {2,3}, {1,3}}},
  35                 { 0x02C, {{1,1}, {1,2}, {1,8}}},
  36                 { 0x048, {{1,2}, {1,2}, {1,4}}},
  37                 { 0x04A, {{1,2}, {1,2}, {1,6}}},
  38                 { 0x04C, {{1,2}, {1,2}, {1,8}}},
  39                 { 0x05A, {{1,2}, {1,3}, {1,6}}},
  40                 { 0x05C, {{1,2}, {1,3}, {1,6}}},
  41                 { 0x063, {{1,2}, {1,4}, {1,4}}},
  42                 { 0x06C, {{1,2}, {1,4}, {1,8}}},
  43                 { 0x091, {{1,3}, {1,3}, {1,6}}},
  44                 { 0x093, {{1,3}, {1,3}, {1,6}}},
  45                 { 0x0A3, {{1,3}, {1,6}, {1,6}}},
  46                 { 0x0DA, {{1,4}, {1,4}, {1,8}}},
  47                 { 0x0DC, {{1,4}, {1,4}, {1,8}}},
  48                 { 0x0EC, {{1,4}, {1,8}, {1,8}}},
  49                 { 0x123, {{1,4}, {1,4}, {1,8}}},
  50                 { 0x16C, {{1,4}, {1,8}, {1,8}}},
  51         };
  52
  53         struct memclk_data {
  54                 unsigned char multiplier;
  55                 unsigned char divisor;
  56         };
  57         static struct memclk_data st40_memclk_table[8] = {
  58                 {1,1},  // 000
  59                 {1,2},  // 001
  60                 {1,3},  // 010
  61                 {2,3},  // 011
  62                 {1,4},  // 100
  63                 {1,6},  // 101
  64                 {1,8},  // 110
  65                 {1,8}   // 111
  66         };
  67
  68         unsigned long pvr;
  69
  70         /*
  71          * This should probably be moved into the SH3 probing code, and then
  72          * use the processor structure to determine which CPU we are running
  73          * on.
  74          */
  75         pvr = ctrl_inl(CCN_PVR);
  76         printk("PVR %08x\n", pvr);
  77
  78         if (((pvr >> CCN_PVR_CHIP_SHIFT) & CCN_PVR_CHIP_MASK) == CCN_PVR_CHIP_ST40STB1) {
  79                 /*
  80                  * Unfortunatly the STB1 FRQCR values are different from the
  81                  * 7750 ones.
  82                  */
  83                 struct frqcr_data *d;
  84                 int a;
  85                 unsigned long memclkcr;
  86                 struct memclk_data *e;
  87
  88                 for (a=0; a<ARRAY_SIZE(st40_frqcr_table); a++) {
  89                         d = &st40_frqcr_table[a];
  90                         if (d->frqcr == (frqcr & 0x1ff))
  91                                 break;
  92                 }
  93                 if (a == ARRAY_SIZE(st40_frqcr_table)) {
  94                         d = st40_frqcr_table;
  95                         printk("ERROR: Unrecognised FRQCR value, using default multipliers\n");
  96                 }
  97
  98                 memclkcr = ctrl_inl(CLOCKGEN_MEMCLKCR);
  99                 e = &st40_memclk_table[memclkcr & MEMCLKCR_RATIO_MASK];
 100
 101                 printk("Clock multipliers: CPU: %d/%d Bus: %d/%d Mem: %d/%d Periph: %d/%d\n",
 102                        d->factor[0].multiplier, d->factor[0].divisor,
 103                        d->factor[1].multiplier, d->factor[1].divisor,
 104                        e->multiplier,           e->divisor,
 105                        d->factor[2].multiplier, d->factor[2].divisor);
 106
 107                 current_cpu_data.master_clock = current_cpu_data.module_clock *
 108                                                 d->factor[2].divisor /
 109                                                 d->factor[2].multiplier;
 110                 current_cpu_data.bus_clock    = current_cpu_data.master_clock *
 111                                                 d->factor[1].multiplier /
 112                                                 d->factor[1].divisor;
 113                 current_cpu_data.memory_clock = current_cpu_data.master_clock *
 114                                                 e->multiplier / e->divisor;
 115                 current_cpu_data.cpu_clock    = current_cpu_data.master_clock *
 116                                                 d->factor[0].multiplier /
 117                                                 d->factor[0].divisor;
 118 }
 119