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author | Catalin Marinas <catalin.marinas@arm.com> | 2012-03-05 12:49:32 +0100 |
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committer | Catalin Marinas <catalin.marinas@arm.com> | 2012-09-17 14:42:13 +0200 |
commit | 53631b54c8704fe5de435582c82ddbc0bfabf06a (patch) | |
tree | 3bca49152b4e2eeaf7a96f2405ed963ce17da1e5 /arch/arm64/kernel/entry-fpsimd.S | |
parent | arm64: 32-bit (compat) applications support (diff) | |
download | linux-53631b54c8704fe5de435582c82ddbc0bfabf06a.tar.xz linux-53631b54c8704fe5de435582c82ddbc0bfabf06a.zip |
arm64: Floating point and SIMD
This patch adds support for FP/ASIMD register bank saving and restoring
during context switch and FP exception handling to generate SIGFPE.
There are 32 128-bit registers and the context switching is currently
done non-lazily. Benchmarks on real hardware are required before
implementing lazy FP state saving/restoring.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Olof Johansson <olof@lixom.net>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Diffstat (limited to 'arch/arm64/kernel/entry-fpsimd.S')
-rw-r--r-- | arch/arm64/kernel/entry-fpsimd.S | 80 |
1 files changed, 80 insertions, 0 deletions
diff --git a/arch/arm64/kernel/entry-fpsimd.S b/arch/arm64/kernel/entry-fpsimd.S new file mode 100644 index 000000000000..17988a6e7ea2 --- /dev/null +++ b/arch/arm64/kernel/entry-fpsimd.S @@ -0,0 +1,80 @@ +/* + * FP/SIMD state saving and restoring + * + * Copyright (C) 2012 ARM Ltd. + * Author: Catalin Marinas <catalin.marinas@arm.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <linux/linkage.h> + +#include <asm/assembler.h> + +/* + * Save the FP registers. + * + * x0 - pointer to struct fpsimd_state + */ +ENTRY(fpsimd_save_state) + stp q0, q1, [x0, #16 * 0] + stp q2, q3, [x0, #16 * 2] + stp q4, q5, [x0, #16 * 4] + stp q6, q7, [x0, #16 * 6] + stp q8, q9, [x0, #16 * 8] + stp q10, q11, [x0, #16 * 10] + stp q12, q13, [x0, #16 * 12] + stp q14, q15, [x0, #16 * 14] + stp q16, q17, [x0, #16 * 16] + stp q18, q19, [x0, #16 * 18] + stp q20, q21, [x0, #16 * 20] + stp q22, q23, [x0, #16 * 22] + stp q24, q25, [x0, #16 * 24] + stp q26, q27, [x0, #16 * 26] + stp q28, q29, [x0, #16 * 28] + stp q30, q31, [x0, #16 * 30]! + mrs x8, fpsr + str w8, [x0, #16 * 2] + mrs x8, fpcr + str w8, [x0, #16 * 2 + 4] + ret +ENDPROC(fpsimd_save_state) + +/* + * Load the FP registers. + * + * x0 - pointer to struct fpsimd_state + */ +ENTRY(fpsimd_load_state) + ldp q0, q1, [x0, #16 * 0] + ldp q2, q3, [x0, #16 * 2] + ldp q4, q5, [x0, #16 * 4] + ldp q6, q7, [x0, #16 * 6] + ldp q8, q9, [x0, #16 * 8] + ldp q10, q11, [x0, #16 * 10] + ldp q12, q13, [x0, #16 * 12] + ldp q14, q15, [x0, #16 * 14] + ldp q16, q17, [x0, #16 * 16] + ldp q18, q19, [x0, #16 * 18] + ldp q20, q21, [x0, #16 * 20] + ldp q22, q23, [x0, #16 * 22] + ldp q24, q25, [x0, #16 * 24] + ldp q26, q27, [x0, #16 * 26] + ldp q28, q29, [x0, #16 * 28] + ldp q30, q31, [x0, #16 * 30]! + ldr w8, [x0, #16 * 2] + ldr w9, [x0, #16 * 2 + 4] + msr fpsr, x8 + msr fpcr, x9 + ret +ENDPROC(fpsimd_load_state) |