diff options
| author | Furquan Shaikh <furquan@google.com> | 2014-08-31 12:21:37 -0700 |
|---|---|---|
| committer | Patrick Georgi <pgeorgi@google.com> | 2015-03-28 07:04:26 +0100 |
| commit | 2157ba76f2fe238cb6bcc97957ac5481df599415 (patch) | |
| tree | 113983986fbffe55988f6c68e8d68fe9af30a66d /src/arch/arm64 | |
| parent | 159aa125ab86a09e2c31f9f1b09eaa6ec8fd396a (diff) | |
arm64: Add support for read and write registers at current EL in assembly
In order to ease the process of reading and writing any register at current EL,
provide read_current and write_current assembly macros. These are included in
arch/lib_helpers.h under the __ASSEMBLY__ macro condition. This is done to allow
the same header file to be included by .c and .S files.
BUG=chrome-os-partner:30785
BRANCH=None
TEST=Compiles successfully
Change-Id: I51749b6e4ae7b1ffbaae28d915cd100a28959f26
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: c11c7287f507fa398cbbee75abc2bd11140ef19b
Original-Change-Id: I1258850438624abfe3b1ed7240df0db0e7905be6
Original-Signed-off-by: Furquan Shaikh <furquan@google.com>
Original-Reviewed-on: https://chromium-review.googlesource.com/216373
Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Original-Reviewed-by: Tom Warren <twarren@nvidia.com>
Original-Tested-by: Furquan Shaikh <furquan@chromium.org>
Original-Commit-Queue: Furquan Shaikh <furquan@chromium.org>
Reviewed-on: http://review.coreboot.org/9062
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Diffstat (limited to 'src/arch/arm64')
| -rw-r--r-- | src/arch/arm64/include/armv8/arch/lib_helpers.h | 97 |
1 files changed, 97 insertions, 0 deletions
diff --git a/src/arch/arm64/include/armv8/arch/lib_helpers.h b/src/arch/arm64/include/armv8/arch/lib_helpers.h index 57b63d8684..958b8e7206 100644 --- a/src/arch/arm64/include/armv8/arch/lib_helpers.h +++ b/src/arch/arm64/include/armv8/arch/lib_helpers.h @@ -22,6 +22,9 @@ * file. */ +#ifndef __ARCH_LIB_HELPERS_H__ +#define __ARCH_LIB_HELPERS_H__ + #define EL0 0 #define EL1 1 #define EL2 2 @@ -30,6 +33,96 @@ #define CURRENT_EL_MASK 0x3 #define CURRENT_EL_SHIFT 2 +#ifdef __ASSEMBLY__ + +/* Macro to switch to label based on current el */ +.macro switch_el xreg label1 label2 label3 + mrs \xreg, CurrentEL + /* Currently at EL1 */ + cmp \xreg, #(EL1 << CURRENT_EL_SHIFT) + b.eq \label1 + /* Currently at EL2 */ + cmp \xreg, #(EL2 << CURRENT_EL_SHIFT) + b.eq \label2 + /* Currently at EL3 */ + cmp \xreg, #(EL3 << CURRENT_EL_SHIFT) + b.eq \label3 +.endm + +/* Macro to read sysreg at current EL + xreg - reg in which read value needs to be stored + sysreg - system reg that is to be read +*/ +.macro read_current xreg sysreg + switch_el \xreg, 101f, 102f, 103f +101: + mrs \xreg, \sysreg\()_el1 + b 104f +102: + mrs \xreg, \sysreg\()_el2 + b 104f +103: + mrs \xreg, \sysreg\()_el3 + b 104f +104: +.endm + +/* Macro to write sysreg at current EL + xreg - reg from which value needs to be written + sysreg - system reg that is to be written + temp - temp reg that can be used to read current EL +*/ +.macro write_current sysreg xreg temp + switch_el \temp, 101f, 102f, 103f +101: + msr \sysreg\()_el1, \xreg + b 104f +102: + msr \sysreg\()_el2, \xreg + b 104f +103: + msr \sysreg\()_el3, \xreg + b 104f +104: +.endm + +/* Macro to read sysreg at current EL - 1 + xreg - reg in which read value needs to be stored + sysreg - system reg that is to be read +*/ +.macro read_lower xreg sysreg + switch_el \xreg, 101f, 102f, 103f +101: + b 104f +102: + mrs \xreg, \sysreg\()_el1 + b 104f +103: + mrs \xreg, \sysreg\()_el2 + b 104f +104: +.endm + +/* Macro to write sysreg at current EL - 1 + xreg - reg from which value needs to be written + sysreg - system reg that is to be written + temp - temp reg that can be used to read current EL +*/ +.macro write_lower sysreg xreg temp + switch_el \temp, 101f, 102f, 103f +101: + b 104f +102: + msr \sysreg\()_el1, \xreg + b 104f +103: + msr \sysreg\()_el2, \xreg + b 104f +104: +.endm + +#else + #define DAIF_DBG_BIT (1<<3) #define DAIF_ABT_BIT (1<<2) #define DAIF_IRQ_BIT (1<<1) @@ -290,3 +383,7 @@ void tlbiallis_el2(void); void tlbiallis_el3(void); void tlbiallis_current(void); void tlbivaa_el1(uint64_t va); + +#endif // __ASSEMBLY__ + +#endif // __ARCH_LIB_HELPERS_H__ |