diff options
Diffstat (limited to 'arch/powerpc/xmon/spr_access.S')
| -rw-r--r-- | arch/powerpc/xmon/spr_access.S | 47 |
1 files changed, 47 insertions, 0 deletions
diff --git a/arch/powerpc/xmon/spr_access.S b/arch/powerpc/xmon/spr_access.S new file mode 100644 index 000000000..c308ddf26 --- /dev/null +++ b/arch/powerpc/xmon/spr_access.S @@ -0,0 +1,47 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#include <asm/ppc_asm.h> +#include <asm/asm-compat.h> + +/* unsigned long xmon_mfspr(sprn, default_value) */ +_GLOBAL(xmon_mfspr) + LOAD_REG_ADDR(r5, .Lmfspr_table) + b xmon_mxspr + +/* void xmon_mtspr(sprn, new_value) */ +_GLOBAL(xmon_mtspr) + LOAD_REG_ADDR(r5, .Lmtspr_table) + b xmon_mxspr + +/* + * r3 = sprn + * r4 = default or new value + * r5 = table base + */ +xmon_mxspr: + /* + * To index into the table of mxsprs we need: + * i = (sprn & 0x3ff) * 8 + * or using rwlinm: + * i = (sprn << 3) & (0x3ff << 3) + */ + rlwinm r3, r3, 3, 0x3ff << 3 + add r5, r5, r3 + mtctr r5 + mr r3, r4 /* put default_value in r3 for mfspr */ + bctr + +.Lmfspr_table: + spr = 0 + .rept 1024 + mfspr r3, spr + blr + spr = spr + 1 + .endr + +.Lmtspr_table: + spr = 0 + .rept 1024 + mtspr spr, r4 + blr + spr = spr + 1 + .endr |