arch/arm/include/asm/virt.h

   1 /*
   2  * Copyright (c) 2012 Linaro Limited.
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   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 along
  15  * with this program; if not, write to the Free Software Foundation, Inc.,
  16  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  17  */
  18
  19 #ifndef VIRT_H
  20 #define VIRT_H
  21
  22 #include <asm/ptrace.h>
  23
  24 /*
  25  * Flag indicating that the kernel was not entered in the same mode on every
  26  * CPU.  The zImage loader stashes this value in an SPSR, so we need an
  27  * architecturally defined flag bit here.
  28  */
  29 #define BOOT_CPU_MODE_MISMATCH  PSR_N_BIT
  30
  31 #ifndef __ASSEMBLY__
  32
  33 #ifdef CONFIG_ARM_VIRT_EXT
  34 /*
  35  * __boot_cpu_mode records what mode the primary CPU was booted in.
  36  * A correctly-implemented bootloader must start all CPUs in the same mode:
  37  * if it fails to do this, the flag BOOT_CPU_MODE_MISMATCH is set to indicate
  38  * that some CPU(s) were booted in a different mode.
  39  *
  40  * This allows the kernel to flag an error when the secondaries have come up.
  41  */
  42 extern int __boot_cpu_mode;
  43
  44 void __hyp_set_vectors(unsigned long phys_vector_base);
  45 unsigned long __hyp_get_vectors(void);
  46 #else
  47 #define __boot_cpu_mode (SVC_MODE)
  48 #endif
  49
  50 #ifndef ZIMAGE
  51 void hyp_mode_check(void);
  52
  53 /* Reports the availability of HYP mode */
  54 static inline bool is_hyp_mode_available(void)
  55 {
  56         return ((__boot_cpu_mode & MODE_MASK) == HYP_MODE &&
  57                 !(__boot_cpu_mode & BOOT_CPU_MODE_MISMATCH));
  58 }
  59
  60 /* Check if the bootloader has booted CPUs in different modes */
  61 static inline bool is_hyp_mode_mismatched(void)
  62 {
  63         return !!(__boot_cpu_mode & BOOT_CPU_MODE_MISMATCH);
  64 }
  65 #endif
  66
  67 #endif /* __ASSEMBLY__ */
  68
  69 #endif /* ! VIRT_H */