diff options
Diffstat (limited to 'lib/crypto/powerpc/chacha-p10-glue.c')
| -rw-r--r-- | lib/crypto/powerpc/chacha-p10-glue.c | 100 | 
1 files changed, 100 insertions, 0 deletions
| diff --git a/lib/crypto/powerpc/chacha-p10-glue.c b/lib/crypto/powerpc/chacha-p10-glue.c new file mode 100644 index 000000000000..fcd23c6f1590 --- /dev/null +++ b/lib/crypto/powerpc/chacha-p10-glue.c @@ -0,0 +1,100 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * ChaCha stream cipher (P10 accelerated) + * + * Copyright 2023- IBM Corp. All rights reserved. + */ + +#include <crypto/chacha.h> +#include <crypto/internal/simd.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/cpufeature.h> +#include <linux/sizes.h> +#include <asm/simd.h> +#include <asm/switch_to.h> + +asmlinkage void chacha_p10le_8x(const struct chacha_state *state, u8 *dst, +				const u8 *src, unsigned int len, int nrounds); + +static __ro_after_init DEFINE_STATIC_KEY_FALSE(have_p10); + +static void vsx_begin(void) +{ +	preempt_disable(); +	enable_kernel_vsx(); +} + +static void vsx_end(void) +{ +	disable_kernel_vsx(); +	preempt_enable(); +} + +static void chacha_p10_do_8x(struct chacha_state *state, u8 *dst, const u8 *src, +			     unsigned int bytes, int nrounds) +{ +	unsigned int l = bytes & ~0x0FF; + +	if (l > 0) { +		chacha_p10le_8x(state, dst, src, l, nrounds); +		bytes -= l; +		src += l; +		dst += l; +		state->x[12] += l / CHACHA_BLOCK_SIZE; +	} + +	if (bytes > 0) +		chacha_crypt_generic(state, dst, src, bytes, nrounds); +} + +void hchacha_block_arch(const struct chacha_state *state, +			u32 out[HCHACHA_OUT_WORDS], int nrounds) +{ +	hchacha_block_generic(state, out, nrounds); +} +EXPORT_SYMBOL(hchacha_block_arch); + +void chacha_crypt_arch(struct chacha_state *state, u8 *dst, const u8 *src, +		       unsigned int bytes, int nrounds) +{ +	if (!static_branch_likely(&have_p10) || bytes <= CHACHA_BLOCK_SIZE || +	    !crypto_simd_usable()) +		return chacha_crypt_generic(state, dst, src, bytes, nrounds); + +	do { +		unsigned int todo = min_t(unsigned int, bytes, SZ_4K); + +		vsx_begin(); +		chacha_p10_do_8x(state, dst, src, todo, nrounds); +		vsx_end(); + +		bytes -= todo; +		src += todo; +		dst += todo; +	} while (bytes); +} +EXPORT_SYMBOL(chacha_crypt_arch); + +bool chacha_is_arch_optimized(void) +{ +	return static_key_enabled(&have_p10); +} +EXPORT_SYMBOL(chacha_is_arch_optimized); + +static int __init chacha_p10_init(void) +{ +	if (cpu_has_feature(CPU_FTR_ARCH_31)) +		static_branch_enable(&have_p10); +	return 0; +} +subsys_initcall(chacha_p10_init); + +static void __exit chacha_p10_exit(void) +{ +} +module_exit(chacha_p10_exit); + +MODULE_DESCRIPTION("ChaCha stream cipher (P10 accelerated)"); +MODULE_AUTHOR("Danny Tsen <dtsen@linux.ibm.com>"); +MODULE_LICENSE("GPL v2"); | 
