arch/ppc/platforms/4xx/oak.c

   1 /*
   2  *
   3  *    Copyright (c) 1999-2000 Grant Erickson <grant@lcse.umn.edu>
   4  *
   5  *    Module name: oak.c
   6  *
   7  *    Description:
   8  *      Architecture- / platform-specific boot-time initialization code for
   9  *      the IBM PowerPC 403GCX "Oak" evaluation board. Adapted from original
  10  *      code by Gary Thomas, Cort Dougan <cort@fsmlabs.com>, and Dan Malek
  11  *      <dan@net4x.com>.
  12  *
  13  */
  14
  15 #include <linux/config.h>
  16 #include <linux/init.h>
  17 #include <linux/smp.h>
  18 #include <linux/threads.h>
  19 #include <linux/param.h>
  20 #include <linux/string.h>
  21 #include <linux/initrd.h>
  22 #include <linux/irq.h>
  23 #include <linux/seq_file.h>
  24
  25 #include <asm/board.h>
  26 #include <asm/machdep.h>
  27 #include <asm/page.h>
  28 #include <asm/bootinfo.h>
  29 #include <asm/ppc4xx_pic.h>
  30 #include <asm/time.h>
  31
  32 #include "oak.h"
  33
  34 /* Function Prototypes */
  35
  36 extern void abort(void);
  37
  38 /* Global Variables */
  39
  40 unsigned char __res[sizeof(bd_t)];
  41
  42
  43 /*
  44  * void __init oak_init()
  45  *
  46  * Description:
  47  *   This routine...
  48  *
  49  * Input(s):
  50  *   r3 - Optional pointer to a board information structure.
  51  *   r4 - Optional pointer to the physical starting address of the init RAM
  52  *        disk.
  53  *   r5 - Optional pointer to the physical ending address of the init RAM
  54  *        disk.
  55  *   r6 - Optional pointer to the physical starting address of any kernel
  56  *        command-line parameters.
  57  *   r7 - Optional pointer to the physical ending address of any kernel
  58  *        command-line parameters.
  59  *
  60  * Output(s):
  61  *   N/A
  62  *
  63  * Returns:
  64  *   N/A
  65  *
  66  */
  67 void __init
  68 platform_init(unsigned long r3, unsigned long r4, unsigned long r5,
  69               unsigned long r6, unsigned long r7)
  70 {
  71         parse_bootinfo(find_bootinfo());
  72
  73         /*
  74          * If we were passed in a board information, copy it into the
  75          * residual data area.
  76          */
  77         if (r3) {
  78                 memcpy((void *)__res, (void *)(r3 + KERNELBASE), sizeof(bd_t));
  79         }
  80
  81 #if defined(CONFIG_BLK_DEV_INITRD)
  82         /*
  83          * If the init RAM disk has been configured in, and there's a valid
  84          * starting address for it, set it up.
  85          */
  86         if (r4) {
  87                 initrd_start = r4 + KERNELBASE;
  88                 initrd_end = r5 + KERNELBASE;
  89         }
  90 #endif /* CONFIG_BLK_DEV_INITRD */
  91
  92         /* Copy the kernel command line arguments to a safe place. */
  93
  94         if (r6) {
  95                 *(char *)(r7 + KERNELBASE) = 0;
  96                 strcpy(cmd_line, (char *)(r6 + KERNELBASE));
  97         }
  98
  99         /* Initialize machine-dependency vectors */
 100
 101         ppc_md.setup_arch               = oak_setup_arch;
 102         ppc_md.show_percpuinfo          = oak_show_percpuinfo;
 103         ppc_md.irq_canonicalize         = NULL;
 104         ppc_md.init_IRQ                 = ppc4xx_pic_init;
 105         ppc_md.get_irq                  = NULL;  /* Set in ppc4xx_pic_init() */
 106         ppc_md.init                     = NULL;
 107
 108         ppc_md.restart                  = oak_restart;
 109         ppc_md.power_off                = oak_power_off;
 110         ppc_md.halt                     = oak_halt;
 111
 112         ppc_md.time_init                = oak_time_init;
 113         ppc_md.set_rtc_time             = oak_set_rtc_time;
 114         ppc_md.get_rtc_time             = oak_get_rtc_time;
 115         ppc_md.calibrate_decr           = oak_calibrate_decr;
 116 }
 117
 118 /*
 119  * Document me.
 120  */
 121 void __init
 122 oak_setup_arch(void)
 123 {
 124         /* XXX - Implement me */
 125 }
 126
 127 /*
 128  * int oak_show_percpuinfo()
 129  *
 130  * Description:
 131  *   This routine pretty-prints the platform's internal CPU and bus clock
 132  *   frequencies into the buffer for usage in /proc/cpuinfo.
 133  *
 134  * Input(s):
 135  *  *buffer - Buffer into which CPU and bus clock frequencies are to be
 136  *            printed.
 137  *
 138  * Output(s):
 139  *  *buffer - Buffer with the CPU and bus clock frequencies.
 140  *
 141  * Returns:
 142  *   The number of bytes copied into 'buffer' if OK, otherwise zero or less
 143  *   on error.
 144  */
 145 int
 146 oak_show_percpuinfo(struct seq_file *m, int i)
 147 {
 148         bd_t *bp = (bd_t *)__res;
 149
 150         seq_printf(m, "clock\t\t: %dMHz\n"
 151                    "bus clock\t\t: %dMHz\n",
 152                    bp->bi_intfreq / 1000000,
 153                    bp->bi_busfreq / 1000000);
 154
 155         return 0;
 156 }
 157
 158 /*
 159  * Document me.
 160  */
 161 void
 162 oak_restart(char *cmd)
 163 {
 164         abort();
 165 }
 166
 167 /*
 168  * Document me.
 169  */
 170 void
 171 oak_power_off(void)
 172 {
 173         oak_restart(NULL);
 174 }
 175
 176 /*
 177  * Document me.
 178  */
 179 void
 180 oak_halt(void)
 181 {
 182         oak_restart(NULL);
 183 }
 184
 185 /*
 186  * Document me.
 187  */
 188 long __init
 189 oak_time_init(void)
 190 {
 191         /* XXX - Implement me */
 192         return 0;
 193 }
 194
 195 /*
 196  * Document me.
 197  */
 198 int __init
 199 oak_set_rtc_time(unsigned long time)
 200 {
 201         /* XXX - Implement me */
 202
 203         return (0);
 204 }
 205
 206 /*
 207  * Document me.
 208  */
 209 unsigned long __init
 210 oak_get_rtc_time(void)
 211 {
 212         /* XXX - Implement me */
 213
 214         return (0);
 215 }
 216
 217 /*
 218  * void __init oak_calibrate_decr()
 219  *
 220  * Description:
 221  *   This routine retrieves the internal processor frequency from the board
 222  *   information structure, sets up the kernel timer decrementer based on
 223  *   that value, enables the 403 programmable interval timer (PIT) and sets
 224  *   it up for auto-reload.
 225  *
 226  * Input(s):
 227  *   N/A
 228  *
 229  * Output(s):
 230  *   N/A
 231  *
 232  * Returns:
 233  *   N/A
 234  *
 235  */
 236 void __init
 237 oak_calibrate_decr(void)
 238 {
 239         unsigned int freq;
 240         bd_t *bip = (bd_t *)__res;
 241
 242         freq = bip->bi_intfreq;
 243
 244         decrementer_count = freq / HZ;
 245         count_period_num = 1;
 246         count_period_den = freq;
 247
 248         /* Enable the PIT and set auto-reload of its value */
 249
 250         mtspr(SPRN_TCR, TCR_PIE | TCR_ARE);
 251
 252         /* Clear any pending timer interrupts */
 253
 254         mtspr(SPRN_TSR, TSR_ENW | TSR_WIS | TSR_PIS | TSR_FIS);
 255 }