sparc/prom/ranges.c

0001 // SPDX-License-Identifier: GPL-2.0
0002 /*
0003  * ranges.c: Handle ranges in newer proms for obio/sbus.
0004  *
0005  * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
0006  * Copyright (C) 1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
0007  */
0008
0009 #include <linux/init.h>
0010 #include <linux/module.h>
0011
0012 #include <asm/openprom.h>
0013 #include <asm/oplib.h>
0014 #include <asm/types.h>
0015
0016 static struct linux_prom_ranges promlib_obio_ranges[PROMREG_MAX];
0017 static int num_obio_ranges;
0018
0019 /* Adjust register values based upon the ranges parameters. */
0020 static void prom_adjust_regs(struct linux_prom_registers *regp, int nregs,
0021                  struct linux_prom_ranges *rangep, int nranges)
0022 {
0023     int regc, rngc;
0024
0025     for (regc = 0; regc < nregs; regc++) {
0026         for (rngc = 0; rngc < nranges; rngc++)
0027             if (regp[regc].which_io == rangep[rngc].ot_child_space)
0028                 break; /* Fount it */
0029         if (rngc == nranges) /* oops */
0030             prom_printf("adjust_regs: Could not find range with matching bus type...\n");
0031         regp[regc].which_io = rangep[rngc].ot_parent_space;
0032         regp[regc].phys_addr -= rangep[rngc].ot_child_base;
0033         regp[regc].phys_addr += rangep[rngc].ot_parent_base;
0034     }
0035 }
0036
0037 static void prom_adjust_ranges(struct linux_prom_ranges *ranges1, int nranges1,
0038                    struct linux_prom_ranges *ranges2, int nranges2)
0039 {
0040     int rng1c, rng2c;
0041
0042     for (rng1c = 0; rng1c < nranges1; rng1c++) {
0043         for (rng2c = 0; rng2c < nranges2; rng2c++)
0044             if (ranges1[rng1c].ot_parent_space == ranges2[rng2c].ot_child_space &&
0045                ranges1[rng1c].ot_parent_base >= ranges2[rng2c].ot_child_base &&
0046                ranges2[rng2c].ot_child_base + ranges2[rng2c].or_size - ranges1[rng1c].ot_parent_base > 0U)
0047             break;
0048         if (rng2c == nranges2) /* oops */
0049             prom_printf("adjust_ranges: Could not find matching bus type...\n");
0050         else if (ranges1[rng1c].ot_parent_base + ranges1[rng1c].or_size > ranges2[rng2c].ot_child_base + ranges2[rng2c].or_size)
0051             ranges1[rng1c].or_size = ranges2[rng2c].ot_child_base + ranges2[rng2c].or_size - ranges1[rng1c].ot_parent_base;
0052         ranges1[rng1c].ot_parent_space = ranges2[rng2c].ot_parent_space;
0053         ranges1[rng1c].ot_parent_base += ranges2[rng2c].ot_parent_base;
0054     }
0055 }
0056
0057 /* Apply probed obio ranges to registers passed, if no ranges return. */
0058 void prom_apply_obio_ranges(struct linux_prom_registers *regs, int nregs)
0059 {
0060     if (num_obio_ranges)
0061         prom_adjust_regs(regs, nregs, promlib_obio_ranges, num_obio_ranges);
0062 }
0063 EXPORT_SYMBOL(prom_apply_obio_ranges);
0064
0065 void __init prom_ranges_init(void)
0066 {
0067     phandle node, obio_node;
0068     int success;
0069
0070     num_obio_ranges = 0;
0071
0072     /* Check for obio and sbus ranges. */
0073     node = prom_getchild(prom_root_node);
0074     obio_node = prom_searchsiblings(node, "obio");
0075
0076     if (obio_node) {
0077         success = prom_getproperty(obio_node, "ranges",
0078                        (char *) promlib_obio_ranges,
0079                        sizeof(promlib_obio_ranges));
0080         if (success != -1)
0081             num_obio_ranges = (success / sizeof(struct linux_prom_ranges));
0082     }
0083
0084     if (num_obio_ranges)
0085         prom_printf("PROMLIB: obio_ranges %d\n", num_obio_ranges);
0086 }
0087
0088 void prom_apply_generic_ranges(phandle node, phandle parent,
0089                    struct linux_prom_registers *regs, int nregs)
0090 {
0091     int success;
0092     int num_ranges;
0093     struct linux_prom_ranges ranges[PROMREG_MAX];
0094
0095     success = prom_getproperty(node, "ranges",
0096                    (char *) ranges,
0097                    sizeof(ranges));
0098     if (success != -1) {
0099         num_ranges = (success / sizeof(struct linux_prom_ranges));
0100         if (parent) {
0101             struct linux_prom_ranges parent_ranges[PROMREG_MAX];
0102             int num_parent_ranges;
0103
0104             success = prom_getproperty(parent, "ranges",
0105                            (char *) parent_ranges,
0106                            sizeof(parent_ranges));
0107             if (success != -1) {
0108                 num_parent_ranges = (success / sizeof(struct linux_prom_ranges));
0109                 prom_adjust_ranges(ranges, num_ranges, parent_ranges, num_parent_ranges);
0110             }
0111         }
0112         prom_adjust_regs(regs, nregs, ranges, num_ranges);
0113     }
0114 }