1 files changed, 377 insertions, 0 deletions
diff --git a/tools/testing/selftests/riscv/hwprobe/cbo.c b/tools/testing/selftests/riscv/hwprobe/cbo.c
new file mode 100644
index 000000000000..f254b2edd6ce
--- /dev/null
+++ b/tools/testing/selftests/riscv/hwprobe/cbo.c
@@ -0,0 +1,377 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2023 Ventana Micro Systems Inc.
+ *
+ * Run with 'taskset -c <cpu-list> cbo' to only execute hwprobe on a
+ * subset of cpus, as well as only executing the tests on those cpus.
+ */
+#define _GNU_SOURCE
+#include <stdbool.h>
+#include <stdint.h>
+#include <string.h>
+#include <sched.h>
+#include <signal.h>
+#include <assert.h>
+#include <linux/compiler.h>
+#include <linux/kernel.h>
+#include <asm/ucontext.h>
+#include <getopt.h>
+
+#include "hwprobe.h"
+#include "kselftest.h"
+
+#define MK_CBO(fn) le32_bswap((uint32_t)(fn) << 20 | 10 << 15 | 2 << 12 | 0 << 7 | 15)
+#define MK_PREFETCH(fn) \
+	le32_bswap(0 << 25 | (uint32_t)(fn) << 20 | 10 << 15 | 6 << 12 | 0 << 7 | 19)
+
+static char mem[4096] __aligned(4096) = { [0 ... 4095] = 0xa5 };
+
+static bool got_fault;
+
+static void fault_handler(int sig, siginfo_t *info, void *context)
+{
+	unsigned long *regs = (unsigned long *)&((ucontext_t *)context)->uc_mcontext;
+	uint32_t insn = *(uint32_t *)regs[0];
+
+	if (sig == SIGILL)
+		assert(insn == MK_CBO(regs[11]));
+
+	if (sig == SIGSEGV || sig == SIGBUS)
+		assert(insn == MK_PREFETCH(regs[11]));
+
+	got_fault = true;
+	regs[0] += 4;
+}
+
+#define cbo_insn(base, fn)							\
+({										\
+	asm volatile(								\
+	"mv	a0, %0\n"							\
+	"li	a1, %1\n"							\
+	".4byte	%2\n"								\
+	: : "r" (base), "i" (fn), "i" (MK_CBO(fn)) : "a0", "a1", "memory");	\
+})
+
+#define prefetch_insn(base, fn)							\
+({										\
+	asm volatile(								\
+	"mv	a0, %0\n"							\
+	"li	a1, %1\n"							\
+	".4byte	%2\n"								\
+	: : "r" (base), "i" (fn), "i" (MK_PREFETCH(fn)) : "a0", "a1");		\
+})
+
+static void cbo_inval(char *base) { cbo_insn(base, 0); }
+static void cbo_clean(char *base) { cbo_insn(base, 1); }
+static void cbo_flush(char *base) { cbo_insn(base, 2); }
+static void cbo_zero(char *base)  { cbo_insn(base, 4); }
+static void prefetch_i(char *base) { prefetch_insn(base, 0); }
+static void prefetch_r(char *base) { prefetch_insn(base, 1); }
+static void prefetch_w(char *base) { prefetch_insn(base, 3); }
+
+static void test_no_cbo_inval(void *arg)
+{
+	ksft_print_msg("Testing cbo.inval instruction remain privileged\n");
+	got_fault = false;
+	cbo_inval(&mem[0]);
+	ksft_test_result(got_fault, "No cbo.inval\n");
+}
+
+static void test_no_zicbom(void *arg)
+{
+	ksft_print_msg("Testing Zicbom instructions remain privileged\n");
+
+	got_fault = false;
+	cbo_clean(&mem[0]);
+	ksft_test_result(got_fault, "No cbo.clean\n");
+
+	got_fault = false;
+	cbo_flush(&mem[0]);
+	ksft_test_result(got_fault, "No cbo.flush\n");
+}
+
+static void test_no_zicboz(void *arg)
+{
+	ksft_print_msg("No Zicboz, testing cbo.zero remains privileged\n");
+
+	got_fault = false;
+	cbo_zero(&mem[0]);
+	ksft_test_result(got_fault, "No cbo.zero\n");
+}
+
+static bool is_power_of_2(__u64 n)
+{
+	return n != 0 && (n & (n - 1)) == 0;
+}
+
+static void test_zicbop(void *arg)
+{
+	struct riscv_hwprobe pair = {
+		.key = RISCV_HWPROBE_KEY_ZICBOP_BLOCK_SIZE,
+	};
+	struct sigaction act = {
+		.sa_sigaction = &fault_handler,
+		.sa_flags = SA_SIGINFO
+	};
+	struct sigaction dfl = {
+		.sa_handler = SIG_DFL
+	};
+	cpu_set_t *cpus = (cpu_set_t *)arg;
+	__u64 block_size;
+	long rc;
+
+	rc = sigaction(SIGSEGV, &act, NULL);
+	assert(rc == 0);
+	rc = sigaction(SIGBUS, &act, NULL);
+	assert(rc == 0);
+
+	rc = riscv_hwprobe(&pair, 1, sizeof(cpu_set_t), (unsigned long *)cpus, 0);
+	block_size = pair.value;
+	ksft_test_result(rc == 0 && pair.key == RISCV_HWPROBE_KEY_ZICBOP_BLOCK_SIZE &&
+			 is_power_of_2(block_size), "Zicbop block size\n");
+	ksft_print_msg("Zicbop block size: %llu\n", block_size);
+
+	got_fault = false;
+	prefetch_i(&mem[0]);
+	prefetch_r(&mem[0]);
+	prefetch_w(&mem[0]);
+	ksft_test_result(!got_fault, "Zicbop prefetch.* on valid address\n");
+
+	got_fault = false;
+	prefetch_i(NULL);
+	prefetch_r(NULL);
+	prefetch_w(NULL);
+	ksft_test_result(!got_fault, "Zicbop prefetch.* on NULL\n");
+
+	rc = sigaction(SIGBUS, &dfl, NULL);
+	assert(rc == 0);
+	rc = sigaction(SIGSEGV, &dfl, NULL);
+	assert(rc == 0);
+}
+
+static void test_zicbom(void *arg)
+{
+	struct riscv_hwprobe pair = {
+		.key = RISCV_HWPROBE_KEY_ZICBOM_BLOCK_SIZE,
+	};
+	cpu_set_t *cpus = (cpu_set_t *)arg;
+	__u64 block_size;
+	long rc;
+
+	rc = riscv_hwprobe(&pair, 1, sizeof(cpu_set_t), (unsigned long *)cpus, 0);
+	block_size = pair.value;
+	ksft_test_result(rc == 0 && pair.key == RISCV_HWPROBE_KEY_ZICBOM_BLOCK_SIZE &&
+			 is_power_of_2(block_size), "Zicbom block size\n");
+	ksft_print_msg("Zicbom block size: %llu\n", block_size);
+
+	got_fault = false;
+	cbo_clean(&mem[block_size]);
+	ksft_test_result(!got_fault, "cbo.clean\n");
+
+	got_fault = false;
+	cbo_flush(&mem[block_size]);
+	ksft_test_result(!got_fault, "cbo.flush\n");
+}
+
+static void test_zicboz(void *arg)
+{
+	struct riscv_hwprobe pair = {
+		.key = RISCV_HWPROBE_KEY_ZICBOZ_BLOCK_SIZE,
+	};
+	cpu_set_t *cpus = (cpu_set_t *)arg;
+	__u64 block_size;
+	int i, j;
+	long rc;
+
+	rc = riscv_hwprobe(&pair, 1, sizeof(cpu_set_t), (unsigned long *)cpus, 0);
+	block_size = pair.value;
+	ksft_test_result(rc == 0 && pair.key == RISCV_HWPROBE_KEY_ZICBOZ_BLOCK_SIZE &&
+			 is_power_of_2(block_size), "Zicboz block size\n");
+	ksft_print_msg("Zicboz block size: %llu\n", block_size);
+
+	got_fault = false;
+	cbo_zero(&mem[block_size]);
+	ksft_test_result(!got_fault, "cbo.zero\n");
+
+	if (got_fault || !is_power_of_2(block_size)) {
+		ksft_test_result_skip("cbo.zero check\n");
+		return;
+	}
+
+	assert(block_size <= 1024);
+
+	for (i = 0; i < 4096 / block_size; ++i) {
+		if (i % 2)
+			cbo_zero(&mem[i * block_size]);
+	}
+
+	for (i = 0; i < 4096 / block_size; ++i) {
+		char expected = i % 2 ? 0x0 : 0xa5;
+
+		for (j = 0; j < block_size; ++j) {
+			if (mem[i * block_size + j] != expected) {
+				ksft_test_result_fail("cbo.zero check\n");
+				ksft_print_msg("cbo.zero check: mem[%llu] != 0x%x\n",
+					       i * block_size + j, expected);
+				return;
+			}
+		}
+	}
+
+	ksft_test_result_pass("cbo.zero check\n");
+}
+
+static void check_no_zicbo_cpus(cpu_set_t *cpus, __u64 cbo)
+{
+	struct riscv_hwprobe pair = {
+		.key = RISCV_HWPROBE_KEY_IMA_EXT_0,
+	};
+	cpu_set_t one_cpu;
+	int i = 0, c = 0;
+	long rc;
+	char *cbostr;
+
+	while (i++ < CPU_COUNT(cpus)) {
+		while (!CPU_ISSET(c, cpus))
+			++c;
+
+		CPU_ZERO(&one_cpu);
+		CPU_SET(c, &one_cpu);
+
+		rc = riscv_hwprobe(&pair, 1, sizeof(cpu_set_t), (unsigned long *)&one_cpu, 0);
+		assert(rc == 0 && pair.key == RISCV_HWPROBE_KEY_IMA_EXT_0);
+
+		switch (cbo) {
+		case RISCV_HWPROBE_EXT_ZICBOZ:
+			cbostr = "Zicboz";
+			break;
+		case RISCV_HWPROBE_EXT_ZICBOM:
+			cbostr = "Zicbom";
+			break;
+		case RISCV_HWPROBE_EXT_ZICBOP:
+			cbostr = "Zicbop";
+			break;
+		default:
+			ksft_exit_fail_msg("Internal error: invalid cbo %llu\n", cbo);
+		}
+
+		if (pair.value & cbo)
+			ksft_exit_fail_msg("%s is only present on a subset of harts.\n"
+					   "Use taskset to select a set of harts where %s\n"
+					   "presence (present or not) is consistent for each hart\n",
+					   cbostr, cbostr);
+		++c;
+	}
+}
+
+enum {
+	TEST_ZICBOZ,
+	TEST_NO_ZICBOZ,
+	TEST_ZICBOM,
+	TEST_NO_ZICBOM,
+	TEST_NO_CBO_INVAL,
+	TEST_ZICBOP,
+};
+
+static struct test_info {
+	bool enabled;
+	unsigned int nr_tests;
+	void (*test_fn)(void *arg);
+} tests[] = {
+	[TEST_ZICBOZ]		= { .nr_tests = 3, test_zicboz },
+	[TEST_NO_ZICBOZ]	= { .nr_tests = 1, test_no_zicboz },
+	[TEST_ZICBOM]		= { .nr_tests = 3, test_zicbom },
+	[TEST_NO_ZICBOM]	= { .nr_tests = 2, test_no_zicbom },
+	[TEST_NO_CBO_INVAL]	= { .nr_tests = 1, test_no_cbo_inval },
+	[TEST_ZICBOP]		= { .nr_tests = 3, test_zicbop },
+};
+
+static const struct option long_opts[] = {
+	{"zicbom-raises-sigill", no_argument, 0, 'm'},
+	{"zicboz-raises-sigill", no_argument, 0, 'z'},
+	{0, 0, 0, 0}
+};
+
+int main(int argc, char **argv)
+{
+	struct sigaction act = {
+		.sa_sigaction = &fault_handler,
+		.sa_flags = SA_SIGINFO,
+	};
+	struct riscv_hwprobe pair;
+	unsigned int plan = 0;
+	cpu_set_t cpus;
+	long rc;
+	int i, opt, long_index;
+
+	long_index = 0;
+
+	while ((opt = getopt_long(argc, argv, "mz", long_opts, &long_index)) != -1) {
+		switch (opt) {
+		case 'm':
+			tests[TEST_NO_ZICBOM].enabled = true;
+			tests[TEST_NO_CBO_INVAL].enabled = true;
+			rc = sigaction(SIGILL, &act, NULL);
+			assert(rc == 0);
+			break;
+		case 'z':
+			tests[TEST_NO_ZICBOZ].enabled = true;
+			tests[TEST_NO_CBO_INVAL].enabled = true;
+			rc = sigaction(SIGILL, &act, NULL);
+			assert(rc == 0);
+			break;
+		case '?':
+			fprintf(stderr,
+				"Usage: %s [--zicbom-raises-sigill|-m] [--zicboz-raises-sigill|-z]\n",
+				argv[0]);
+			exit(1);
+		default:
+			break;
+		}
+	}
+
+	rc = sched_getaffinity(0, sizeof(cpu_set_t), &cpus);
+	assert(rc == 0);
+
+	ksft_print_header();
+
+	pair.key = RISCV_HWPROBE_KEY_IMA_EXT_0;
+	rc = riscv_hwprobe(&pair, 1, sizeof(cpu_set_t), (unsigned long *)&cpus, 0);
+	if (rc < 0)
+		ksft_exit_fail_msg("hwprobe() failed with %ld\n", rc);
+	assert(rc == 0 && pair.key == RISCV_HWPROBE_KEY_IMA_EXT_0);
+
+	if (pair.value & RISCV_HWPROBE_EXT_ZICBOZ) {
+		tests[TEST_ZICBOZ].enabled = true;
+		tests[TEST_NO_ZICBOZ].enabled = false;
+	} else {
+		check_no_zicbo_cpus(&cpus, RISCV_HWPROBE_EXT_ZICBOZ);
+	}
+
+	if (pair.value & RISCV_HWPROBE_EXT_ZICBOM) {
+		tests[TEST_ZICBOM].enabled = true;
+		tests[TEST_NO_ZICBOM].enabled = false;
+	} else {
+		check_no_zicbo_cpus(&cpus, RISCV_HWPROBE_EXT_ZICBOM);
+	}
+
+	if (pair.value & RISCV_HWPROBE_EXT_ZICBOP)
+		tests[TEST_ZICBOP].enabled = true;
+	else
+		check_no_zicbo_cpus(&cpus, RISCV_HWPROBE_EXT_ZICBOP);
+
+	for (i = 0; i < ARRAY_SIZE(tests); ++i)
+		plan += tests[i].enabled ? tests[i].nr_tests : 0;
+
+	if (plan == 0)
+		ksft_print_msg("No tests enabled.\n");
+	else
+		ksft_set_plan(plan);
+
+	for (i = 0; i < ARRAY_SIZE(tests); ++i) {
+		if (tests[i].enabled)
+			tests[i].test_fn(&cpus);
+	}
+
+	ksft_finished();
+}