diff options
| author | Etienne Carriere <etienne.carriere@linaro.org> | 2017-11-08 14:38:33 +0100 |
|---|---|---|
| committer | Etienne Carriere <etienne.carriere@linaro.org> | 2017-11-08 14:38:33 +0100 |
| commit | 64cc6e91e819ccbf5fe3bf8a5c177b8fa8012d8c (patch) | |
| tree | 6cc714edf449c3e44fde7840598d30089edd9f57 /include/common | |
| parent | 51b992ecec92b9dcca410a2c3716f45daca5afd1 (diff) | |
ARMv7 may not support Virtualization Extensions
ARMv7-A Virtualization extensions brings new instructions and resources
that were supported by later architectures. Reference ARM ARM Issue C.c
[DDI0406C_C].
ERET and extended MSR/MRS instructions, as specified in [DDI0406C_C] in
ID_PFR1 description of bits[15:12] (Virtualization Extensions):
A value of 0b0001 implies implementation of the HVC, ERET, MRS
(Banked register), and MSR (Banked register) instructions. The ID_ISARs
do not identify whether these instructions are implemented.
UDIV/SDIV were introduced with the Virtualization extensions, even if
not strictly related to the virtualization extensions.
If ARMv7 based platform does not set ARM_CORTEX_Ax=yes, platform
shall define ARMV7_SUPPORTS_VIRTUALIZATION to enable virtualization
extension related resources.
Signed-off-by: Etienne Carriere <etienne.carriere@linaro.org>
Diffstat (limited to 'include/common')
| -rw-r--r-- | include/common/aarch32/asm_macros.S | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/include/common/aarch32/asm_macros.S b/include/common/aarch32/asm_macros.S index 0d1a37d1..74322228 100644 --- a/include/common/aarch32/asm_macros.S +++ b/include/common/aarch32/asm_macros.S @@ -79,6 +79,16 @@ ldr r0, =(\_name + \_size) .endm +#if ARM_ARCH_MAJOR == 7 && !defined(ARMV7_SUPPORTS_VIRTUALIZATION) + /* + * ARMv7 cores without Virtualization extension do not support the + * eret instruction. + */ + .macro eret + movs pc, lr + .endm +#endif + #if (ARM_ARCH_MAJOR == 7) /* ARMv7 does not support stl instruction */ .macro stl _reg, _write_lock |