Commit 49886aa9 authored by Mark Brown's avatar Mark Brown Committed by Catalin Marinas
Browse files

kselftest/arm64: Add SME2 coverage to syscall-abi 



Verify that ZT0 is preserved over syscalls when it is present and
PSTATE.ZA is set.

Signed-off-by: default avatarMark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20221208-arm64-sme2-v4-19-f2fa0aef982f@kernel.org


Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
parent 18f8729a

tools/testing/selftests/arm64/abi/syscall-abi-asm.S

+42 −1
Original line number Diff line number Diff line
@@ -23,6 +23,9 @@ 


.arch_extension sve



#define ID_AA64SMFR0_EL1_SMEver_SHIFT           56

#define ID_AA64SMFR0_EL1_SMEver_WIDTH           4



/*

 * LDR (vector to ZA array):

 *	LDR ZA[\nw, #\offset], [X\nxbase, #\offset, MUL VL]
@@ -45,6 +48,26 @@ 
		| ((\offset) & 7)

.endm



/*

 * LDR (ZT0)

 *

 *	LDR ZT0, nx

 */

.macro _ldr_zt nx

	.inst	0xe11f8000			\

		| (((\nx) & 0x1f) << 5)

.endm



/*

 * STR (ZT0)

 *

 *	STR ZT0, nx

 */

.macro _str_zt nx

	.inst	0xe13f8000			\

		| (((\nx) & 0x1f) << 5)

.endm



.globl do_syscall

do_syscall:

	// Store callee saved registers x19-x29 (80 bytes) plus x0 and x1
@@ -64,7 +87,7 @@ do_syscall: 
	msr	S3_3_C4_C2_2, x2

1:



	// Load ZA if it's enabled - uses x12 as scratch due to SME LDR

	// Load ZA and ZT0 if enabled - uses x12 as scratch due to SME LDR

	tbz	x2, #SVCR_ZA_SHIFT, 1f

	mov	w12, #0

	ldr	x2, =za_in
@@ -73,6 +96,15 @@ do_syscall: 
	add	x12, x12, #1

	cmp	x1, x12

	bne	2b



	// ZT0

	mrs	x2, S3_0_C0_C4_5	// ID_AA64SMFR0_EL1

	ubfx	x2, x2, #ID_AA64SMFR0_EL1_SMEver_SHIFT, \

			 #ID_AA64SMFR0_EL1_SMEver_WIDTH

	cbz	x2, 1f

	adrp	x2, zt_in

	add	x2, x2, :lo12:zt_in

	_ldr_zt 2

1:



	// Load GPRs x8-x28, and save our SP/FP for later comparison
@@ -235,6 +267,15 @@ do_syscall: 
	add	x12, x12, #1

	cmp	x1, x12

	bne	2b



	// ZT0

	mrs	x2, S3_0_C0_C4_5	// ID_AA64SMFR0_EL1

	ubfx	x2, x2, #ID_AA64SMFR0_EL1_SMEver_SHIFT, \

			#ID_AA64SMFR0_EL1_SMEver_WIDTH

	cbz	x2, 1f

	adrp	x2, zt_out

	add	x2, x2, :lo12:zt_out

	_str_zt 2

1:



	// Save the SVE state if we have some

tools/testing/selftests/arm64/abi/syscall-abi.c

+38 −2
Original line number Diff line number Diff line
@@ -311,6 +311,35 @@ static int check_za(struct syscall_cfg *cfg, int sve_vl, int sme_vl, 
	return errors;

}



uint8_t zt_in[ZT_SIG_REG_BYTES] __attribute__((aligned(16)));

uint8_t zt_out[ZT_SIG_REG_BYTES] __attribute__((aligned(16)));



static void setup_zt(struct syscall_cfg *cfg, int sve_vl, int sme_vl,

		     uint64_t svcr)

{

	fill_random(zt_in, sizeof(zt_in));

	memset(zt_out, 0, sizeof(zt_out));

}



static int check_zt(struct syscall_cfg *cfg, int sve_vl, int sme_vl,

		    uint64_t svcr)

{

	int errors = 0;



	if (!(getauxval(AT_HWCAP2) & HWCAP2_SME2))

		return 0;



	if (!(svcr & SVCR_ZA_MASK))

		return 0;



	if (memcmp(zt_in, zt_out, sizeof(zt_in)) != 0) {

		ksft_print_msg("SME VL %d ZT does not match\n", sme_vl);

		errors++;

	}



	return errors;

}



typedef void (*setup_fn)(struct syscall_cfg *cfg, int sve_vl, int sme_vl,

			 uint64_t svcr);

typedef int (*check_fn)(struct syscall_cfg *cfg, int sve_vl, int sme_vl,
@@ -334,6 +363,7 @@ static struct { 
	{ setup_ffr, check_ffr },

	{ setup_svcr, check_svcr },

	{ setup_za, check_za },

	{ setup_zt, check_zt },

};



static bool do_test(struct syscall_cfg *cfg, int sve_vl, int sme_vl,
@@ -474,6 +504,7 @@ int main(void) 
{

	int i;

	int tests = 1;  /* FPSIMD */

	int sme_ver;



	srandom(getpid());
@@ -482,10 +513,15 @@ int main(void) 
	tests += (sve_count_vls() * sme_count_vls()) * 3;

	ksft_set_plan(ARRAY_SIZE(syscalls) * tests);



	if (getauxval(AT_HWCAP2) & HWCAP2_SME2)

		sme_ver = 2;

	else

		sme_ver = 1;



	if (getauxval(AT_HWCAP2) & HWCAP2_SME_FA64)

		ksft_print_msg("SME with FA64\n");

		ksft_print_msg("SME%d with FA64\n", sme_ver);

	else if (getauxval(AT_HWCAP2) & HWCAP2_SME)

		ksft_print_msg("SME without FA64\n");

		ksft_print_msg("SME%d without FA64\n", sme_ver);



	for (i = 0; i < ARRAY_SIZE(syscalls); i++)

		test_one_syscall(&syscalls[i]);