LXR linux/arch/arm/plat-iop/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
  10static 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 */
  27static 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
  35void __init iop_init_cp6_handler(void)
  36{
  37        register_undef_hook(&cp6_hook);
  38}
  39