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. */
prom_adjust_regs(struct linux_prom_registers * regp,int nregs,struct linux_prom_ranges * rangep,int nranges)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
prom_adjust_ranges(struct linux_prom_ranges * ranges1,int nranges1,struct linux_prom_ranges * ranges2,int nranges2)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. */
prom_apply_obio_ranges(struct linux_prom_registers * regs,int nregs)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
prom_ranges_init(void)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
prom_apply_generic_ranges(phandle node,phandle parent,struct linux_prom_registers * regs,int nregs)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 }
115