arch/arm/mach-iop32x/cp6.c

   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
  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
  35 void __init iop_init_cp6_handler(void)
  36 {
  37         register_undef_hook(&cp6_hook);
  38 }