LXR linux/arch/arm64/include/asm/virt.h

   1/*
   2 * Copyright (C) 2012 ARM Ltd.
   3 * Author: Marc Zyngier <marc.zyngier@arm.com>
   4 *
   5 * This program is free software: you can redistribute it and/or modify
   6 * it under the terms of the GNU General Public License version 2 as
   7 * published by the Free Software Foundation.
   8 *
   9 * This program is distributed in the hope that it will be useful,
  10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 * GNU General Public License for more details.
  13 *
  14 * You should have received a copy of the GNU General Public License
  15 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16 */
  17
  18#ifndef __ASM__VIRT_H
  19#define __ASM__VIRT_H
  20
  21/*
  22 * The arm64 hcall implementation uses x0 to specify the hcall
  23 * number. A value less than HVC_STUB_HCALL_NR indicates a special
  24 * hcall, such as set vector. Any other value is handled in a
  25 * hypervisor specific way.
  26 *
  27 * The hypercall is allowed to clobber any of the caller-saved
  28 * registers (x0-x18), so it is advisable to use it through the
  29 * indirection of a function call (as implemented in hyp-stub.S).
  30 */
  31
  32/*
  33 * HVC_SET_VECTORS - Set the value of the vbar_el2 register.
  34 *
  35 * @x1: Physical address of the new vector table.
  36 */
  37#define HVC_SET_VECTORS 0
  38
  39/*
  40 * HVC_SOFT_RESTART - CPU soft reset, used by the cpu_soft_restart routine.
  41 */
  42#define HVC_SOFT_RESTART 1
  43
  44/*
  45 * HVC_RESET_VECTORS - Restore the vectors to the original HYP stubs
  46 */
  47#define HVC_RESET_VECTORS 2
  48
  49/* Max number of HYP stub hypercalls */
  50#define HVC_STUB_HCALL_NR 3
  51
  52/* Error returned when an invalid stub number is passed into x0 */
  53#define HVC_STUB_ERR    0xbadca11
  54
  55#define BOOT_CPU_MODE_EL1       (0xe11)
  56#define BOOT_CPU_MODE_EL2       (0xe12)
  57
  58#ifndef __ASSEMBLY__
  59
  60#include <asm/ptrace.h>
  61#include <asm/sections.h>
  62#include <asm/sysreg.h>
  63#include <asm/cpufeature.h>
  64
  65/*
  66 * __boot_cpu_mode records what mode CPUs were booted in.
  67 * A correctly-implemented bootloader must start all CPUs in the same mode:
  68 * In this case, both 32bit halves of __boot_cpu_mode will contain the
  69 * same value (either 0 if booted in EL1, BOOT_CPU_MODE_EL2 if booted in EL2).
  70 *
  71 * Should the bootloader fail to do this, the two values will be different.
  72 * This allows the kernel to flag an error when the secondaries have come up.
  73 */
  74extern u32 __boot_cpu_mode[2];
  75
  76void __hyp_set_vectors(phys_addr_t phys_vector_base);
  77void __hyp_reset_vectors(void);
  78
  79/* Reports the availability of HYP mode */
  80static inline bool is_hyp_mode_available(void)
  81{
  82        return (__boot_cpu_mode[0] == BOOT_CPU_MODE_EL2 &&
  83                __boot_cpu_mode[1] == BOOT_CPU_MODE_EL2);
  84}
  85
  86/* Check if the bootloader has booted CPUs in different modes */
  87static inline bool is_hyp_mode_mismatched(void)
  88{
  89        return __boot_cpu_mode[0] != __boot_cpu_mode[1];
  90}
  91
  92static inline bool is_kernel_in_hyp_mode(void)
  93{
  94        return read_sysreg(CurrentEL) == CurrentEL_EL2;
  95}
  96
  97static inline bool has_vhe(void)
  98{
  99        if (cpus_have_const_cap(ARM64_HAS_VIRT_HOST_EXTN))
 100                return true;
 101
 102        return false;
 103}
 104
 105#ifdef CONFIG_ARM64_VHE
 106extern void verify_cpu_run_el(void);
 107#else
 108static inline void verify_cpu_run_el(void) {}
 109#endif
 110
 111#endif /* __ASSEMBLY__ */
 112
 113#endif /* ! __ASM__VIRT_H */
 114