arch/sparc/prom/ranges.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * ranges.c: Handle ranges in newer proms for obio/sbus.
   4  *
   5  * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
   6  * Copyright (C) 1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
   7  */
   8
   9 #include <linux/init.h>
  10 #include <linux/module.h>
  11
  12 #include <asm/openprom.h>
  13 #include <asm/oplib.h>
  14 #include <asm/types.h>
  15
  16 static struct linux_prom_ranges promlib_obio_ranges[PROMREG_MAX];
  17 static int num_obio_ranges;
  18
  19 /* Adjust register values based upon the ranges parameters. */
  20 static void prom_adjust_regs(struct linux_prom_registers *regp, int nregs,
  21                              struct linux_prom_ranges *rangep, int nranges)
  22 {
  23         int regc, rngc;
  24
  25         for (regc = 0; regc < nregs; regc++) {
  26                 for (rngc = 0; rngc < nranges; rngc++)
  27                         if (regp[regc].which_io == rangep[rngc].ot_child_space)
  28                                 break; /* Fount it */
  29                 if (rngc == nranges) /* oops */
  30                         prom_printf("adjust_regs: Could not find range with matching bus type...\n");
  31                 regp[regc].which_io = rangep[rngc].ot_parent_space;
  32                 regp[regc].phys_addr -= rangep[rngc].ot_child_base;
  33                 regp[regc].phys_addr += rangep[rngc].ot_parent_base;
  34         }
  35 }
  36
  37 static void prom_adjust_ranges(struct linux_prom_ranges *ranges1, int nranges1,
  38                                struct linux_prom_ranges *ranges2, int nranges2)
  39 {
  40         int rng1c, rng2c;
  41
  42         for (rng1c = 0; rng1c < nranges1; rng1c++) {
  43                 for (rng2c = 0; rng2c < nranges2; rng2c++)
  44                         if (ranges1[rng1c].ot_parent_space == ranges2[rng2c].ot_child_space &&
  45                            ranges1[rng1c].ot_parent_base >= ranges2[rng2c].ot_child_base &&
  46                            ranges2[rng2c].ot_child_base + ranges2[rng2c].or_size - ranges1[rng1c].ot_parent_base > 0U)
  47                         break;
  48                 if (rng2c == nranges2) /* oops */
  49                         prom_printf("adjust_ranges: Could not find matching bus type...\n");
  50                 else if (ranges1[rng1c].ot_parent_base + ranges1[rng1c].or_size > ranges2[rng2c].ot_child_base + ranges2[rng2c].or_size)
  51                         ranges1[rng1c].or_size = ranges2[rng2c].ot_child_base + ranges2[rng2c].or_size - ranges1[rng1c].ot_parent_base;
  52                 ranges1[rng1c].ot_parent_space = ranges2[rng2c].ot_parent_space;
  53                 ranges1[rng1c].ot_parent_base += ranges2[rng2c].ot_parent_base;
  54         }
  55 }
  56
  57 /* Apply probed obio ranges to registers passed, if no ranges return. */
  58 void prom_apply_obio_ranges(struct linux_prom_registers *regs, int nregs)
  59 {
  60         if (num_obio_ranges)
  61                 prom_adjust_regs(regs, nregs, promlib_obio_ranges, num_obio_ranges);
  62 }
  63 EXPORT_SYMBOL(prom_apply_obio_ranges);
  64
  65 void __init prom_ranges_init(void)
  66 {
  67         phandle node, obio_node;
  68         int success;
  69
  70         num_obio_ranges = 0;
  71
  72         /* Check for obio and sbus ranges. */
  73         node = prom_getchild(prom_root_node);
  74         obio_node = prom_searchsiblings(node, "obio");
  75
  76         if (obio_node) {
  77                 success = prom_getproperty(obio_node, "ranges",
  78                                            (char *) promlib_obio_ranges,
  79                                            sizeof(promlib_obio_ranges));
  80                 if (success != -1)
  81                         num_obio_ranges = (success / sizeof(struct linux_prom_ranges));
  82         }
  83
  84         if (num_obio_ranges)
  85                 prom_printf("PROMLIB: obio_ranges %d\n", num_obio_ranges);
  86 }
  87
  88 void prom_apply_generic_ranges(phandle node, phandle parent,
  89                                struct linux_prom_registers *regs, int nregs)
  90 {
  91         int success;
  92         int num_ranges;
  93         struct linux_prom_ranges ranges[PROMREG_MAX];
  94
  95         success = prom_getproperty(node, "ranges",
  96                                    (char *) ranges,
  97                                    sizeof(ranges));
  98         if (success != -1) {
  99                 num_ranges = (success / sizeof(struct linux_prom_ranges));
 100                 if (parent) {
 101                         struct linux_prom_ranges parent_ranges[PROMREG_MAX];
 102                         int num_parent_ranges;
 103
 104                         success = prom_getproperty(parent, "ranges",
 105                                                    (char *) parent_ranges,
 106                                                    sizeof(parent_ranges));
 107                         if (success != -1) {
 108                                 num_parent_ranges = (success / sizeof(struct linux_prom_ranges));
 109                                 prom_adjust_ranges(ranges, num_ranges, parent_ranges, num_parent_ranges);
 110                         }
 111                 }
 112                 prom_adjust_regs(regs, nregs, ranges, num_ranges);
 113         }
 114 }