1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * IOP Coprocessor-6 access handler
4 * Copyright (c) 2006, Intel Corporation.
5 */
6 #include <linux/init.h>
7 #include <asm/traps.h>
8 #include <asm/ptrace.h>
9
cp6_trap(struct pt_regs * regs,unsigned int instr)10 static int cp6_trap(struct pt_regs *regs, unsigned int instr)
11 {
12 u32 temp;
13
14 /* enable cp6 access */
15 asm volatile (
16 "mrc p15, 0, %0, c15, c1, 0\n\t"
17 "orr %0, %0, #(1 << 6)\n\t"
18 "mcr p15, 0, %0, c15, c1, 0\n\t"
19 : "=r"(temp));
20
21 return 0;
22 }
23
24 /* permit kernel space cp6 access
25 * deny user space cp6 access
26 */
27 static struct undef_hook cp6_hook = {
28 .instr_mask = 0x0f000ff0,
29 .instr_val = 0x0e000610,
30 .cpsr_mask = MODE_MASK,
31 .cpsr_val = SVC_MODE,
32 .fn = cp6_trap,
33 };
34
iop_init_cp6_handler(void)35 void __init iop_init_cp6_handler(void)
36 {
37 register_undef_hook(&cp6_hook);
38 }
39