1/* SPDX-License-Identifier: GPL-2.0 */
2#include <asm/ppc_asm.h>
3#include <asm/asm-compat.h>
4
5/* unsigned long xmon_mfspr(sprn, default_value) */
6_GLOBAL(xmon_mfspr)
7 LOAD_REG_ADDR(r5, .Lmfspr_table)
8 b xmon_mxspr
9
10/* void xmon_mtspr(sprn, new_value) */
11_GLOBAL(xmon_mtspr)
12 LOAD_REG_ADDR(r5, .Lmtspr_table)
13 b xmon_mxspr
14
15/*
16 * r3 = sprn
17 * r4 = default or new value
18 * r5 = table base
19 */
20xmon_mxspr:
21 /*
22 * To index into the table of mxsprs we need:
23 * i = (sprn & 0x3ff) * 8
24 * or using rwlinm:
25 * i = (sprn << 3) & (0x3ff << 3)
26 */
27 rlwinm r3, r3, 3, 0x3ff << 3
28 add r5, r5, r3
29 mtctr r5
30 mr r3, r4 /* put default_value in r3 for mfspr */
31 bctr
32
33.Lmfspr_table:
34 spr = 0
35 .rept 1024
36 mfspr r3, spr
37 blr
38 spr = spr + 1
39 .endr
40
41.Lmtspr_table:
42 spr = 0
43 .rept 1024
44 mtspr spr, r4
45 blr
46 spr = spr + 1
47 .endr
48

source code of linux/arch/powerpc/xmon/spr_access.S