[kvm-unit-tests PATCH v5 5/5] riscv: sbi: Add tests for HSM extension

[James Raphael Tiovalen <jamestiotio@gmail.com>]

Add some tests for all of the HSM extension functions. These tests
ensure that the HSM extension functions follow the behavior as described
in the SBI specification.

Signed-off-by: James Raphael Tiovalen <jamestiotio@gmail.com>
---
 riscv/sbi.c | 648 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 648 insertions(+)

diff --git a/riscv/sbi.c b/riscv/sbi.c
index b5147dee..cd1ed95b 100644
--- a/riscv/sbi.c
+++ b/riscv/sbi.c
@@ -6,6 +6,8 @@
  */
 #include <libcflat.h>
 #include <alloc_page.h>
+#include <cpumask.h>
+#include <on-cpus.h>
 #include <stdlib.h>
 #include <string.h>
 #include <limits.h>
@@ -16,12 +18,15 @@
 #include <asm/delay.h>
 #include <asm/io.h>
 #include <asm/mmu.h>
+#include <asm/page.h>
 #include <asm/processor.h>
 #include <asm/sbi.h>
 #include <asm/setup.h>
 #include <asm/smp.h>
 #include <asm/timer.h>
 
+#include "sbi-tests.h"
+
 #define	HIGH_ADDR_BOUNDARY	((phys_addr_t)1 << 32)
 
 static void help(void)
@@ -47,6 +52,11 @@ static struct sbiret sbi_dbcn_write_byte(uint8_t byte)
 	return sbi_ecall(SBI_EXT_DBCN, SBI_EXT_DBCN_CONSOLE_WRITE_BYTE, byte, 0, 0, 0, 0, 0);
 }
 
+static struct sbiret sbi_hart_suspend(uint32_t suspend_type, unsigned long resume_addr, unsigned long opaque)
+{
+	return sbi_ecall(SBI_EXT_HSM, SBI_EXT_HSM_HART_SUSPEND, suspend_type, resume_addr, opaque, 0, 0, 0);
+}
+
 static void split_phys_addr(phys_addr_t paddr, unsigned long *hi, unsigned long *lo)
 {
 	*lo = (unsigned long)paddr;
@@ -433,6 +443,643 @@ static void check_dbcn(void)
 unsigned char sbi_hsm_stop_hart[NR_CPUS];
 unsigned char sbi_hsm_hart_start_checks[NR_CPUS];
 unsigned char sbi_hsm_non_retentive_hart_suspend_checks[NR_CPUS];
+cpumask_t sbi_hsm_started_hart_checks;
+static bool sbi_hsm_invalid_hartid_check;
+static bool sbi_hsm_timer_fired;
+extern void sbi_hsm_check_hart_start(void);
+extern void sbi_hsm_check_non_retentive_suspend(void);
+
+static void hsm_timer_irq_handler(struct pt_regs *regs)
+{
+	sbi_hsm_timer_fired = true;
+	timer_stop();
+}
+
+static void hsm_timer_setup(void)
+{
+	install_irq_handler(IRQ_S_TIMER, hsm_timer_irq_handler);
+	local_irq_enable();
+	timer_irq_enable();
+}
+
+static void hsm_timer_teardown(void)
+{
+	timer_irq_disable();
+	local_irq_disable();
+	install_irq_handler(IRQ_S_TIMER, NULL);
+}
+
+static void hart_empty_fn(void *data) {}
+
+static void hart_execute(void *data)
+{
+	struct sbiret ret;
+	unsigned long hartid = current_thread_info()->hartid;
+	int me = smp_processor_id();
+
+	ret = sbi_hart_start(hartid, virt_to_phys(&hart_empty_fn), 0);
+
+	if (ret.error == SBI_ERR_ALREADY_AVAILABLE)
+		cpumask_set_cpu(me, &sbi_hsm_started_hart_checks);
+}
+
+static void hart_start_invalid_hartid(void *data)
+{
+	struct sbiret ret;
+
+	ret = sbi_hart_start(ULONG_MAX, virt_to_phys(&hart_empty_fn), 0);
+
+	if (ret.error == SBI_ERR_INVALID_PARAM)
+		sbi_hsm_invalid_hartid_check = true;
+}
+
+static void hart_stop(void *data)
+{
+	unsigned long hartid = current_thread_info()->hartid;
+	struct sbiret ret = sbi_hart_stop();
+
+	report_fail("failed to stop hart %ld (error=%ld)", hartid, ret.error);
+}
+
+static void hart_retentive_suspend(void *data)
+{
+	unsigned long hartid = current_thread_info()->hartid;
+	struct sbiret ret = sbi_hart_suspend(SBI_EXT_HSM_HART_SUSPEND_RETENTIVE, 0, 0);
+
+	if (ret.error)
+		report_fail("failed to retentive suspend hart %ld (error=%ld)", hartid, ret.error);
+}
+
+static void hart_non_retentive_suspend(void *data)
+{
+	unsigned long hartid = current_thread_info()->hartid;
+
+	/* Set opaque as hartid so that we can check a0 == a1, ensuring that a0 is hartid and a1 is opaque */
+	struct sbiret ret = sbi_hart_suspend(SBI_EXT_HSM_HART_SUSPEND_NON_RETENTIVE,
+					     virt_to_phys(&sbi_hsm_check_non_retentive_suspend), hartid);
+
+	report_fail("failed to non-retentive suspend hart %ld (error=%ld)", hartid, ret.error);
+}
+
+static void hart_retentive_suspend_with_msb_set(void *data)
+{
+	unsigned long hartid = current_thread_info()->hartid;
+	unsigned long suspend_type = SBI_EXT_HSM_HART_SUSPEND_RETENTIVE | (_AC(1, UL) << (__riscv_xlen - 1));
+	struct sbiret ret = sbi_ecall(SBI_EXT_HSM, SBI_EXT_HSM_HART_SUSPEND, suspend_type, 0, 0, 0, 0, 0);
+
+	if (ret.error)
+		report_fail("failed to retentive suspend hart %ld with MSB set (error=%ld)", hartid, ret.error);
+}
+
+static void hart_non_retentive_suspend_with_msb_set(void *data)
+{
+	unsigned long hartid = current_thread_info()->hartid;
+	unsigned long suspend_type = SBI_EXT_HSM_HART_SUSPEND_NON_RETENTIVE | (_AC(1, UL) << (__riscv_xlen - 1));
+
+	/* Set opaque as hartid so that we can check a0 == a1, ensuring that a0 is hartid and a1 is opaque */
+	struct sbiret ret = sbi_ecall(SBI_EXT_HSM, SBI_EXT_HSM_HART_SUSPEND, suspend_type,
+				      virt_to_phys(&sbi_hsm_check_non_retentive_suspend), hartid, 0, 0, 0);
+
+	report_fail("failed to non-retentive suspend hart %ld with MSB set (error=%ld)", hartid, ret.error);
+}
+
+static bool hart_wait_on_status(unsigned long hartid, enum sbi_ext_hsm_sid status, unsigned long duration)
+{
+	struct sbiret ret;
+
+	sbi_hsm_timer_fired = false;
+	timer_start(duration);
+
+	ret = sbi_hart_get_status(hartid);
+
+	while (!ret.error && ret.value == status && !sbi_hsm_timer_fired) {
+		cpu_relax();
+		ret = sbi_hart_get_status(hartid);
+	}
+
+	timer_stop();
+
+	if (sbi_hsm_timer_fired)
+		report_info("timer fired while waiting on status %u for hart %ld", status, hartid);
+	else if (ret.error)
+		report_fail("got %ld while waiting on status %u for hart %ld\n", ret.error, status, hartid);
+
+	return sbi_hsm_timer_fired || ret.error;
+}
+
+static void check_hsm(void)
+{
+	struct sbiret ret;
+	unsigned long hartid;
+	cpumask_t secondary_cpus_mask, hsm_start, hsm_stop, hsm_suspend, hsm_resume, hsm_check;
+	bool ipi_unavailable = false;
+	bool suspend_with_msb = false, resume_with_msb = false, check_with_msb = false, stop_with_msb = false;
+	int cpu, me = smp_processor_id();
+	int max_cpus = getenv("SBI_MAX_CPUS") ? strtol(getenv("SBI_MAX_CPUS"), NULL, 0) : nr_cpus;
+	unsigned long hsm_timer_duration = getenv("SBI_HSM_TIMER_DURATION")
+					 ? strtol(getenv("SBI_HSM_TIMER_DURATION"), NULL, 0) : 200000;
+
+	max_cpus = MIN(max_cpus, nr_cpus);
+
+	report_prefix_push("hsm");
+
+	if (!sbi_probe(SBI_EXT_HSM)) {
+		report_skip("hsm extension not available");
+		report_prefix_pop();
+		return;
+	}
+
+	report_prefix_push("hart_get_status");
+
+	hartid = current_thread_info()->hartid;
+	ret = sbi_hart_get_status(hartid);
+
+	if (ret.error) {
+		report_fail("failed to get status of current hart (error=%ld)", ret.error);
+		report_prefix_popn(2);
+		return;
+	} else if (ret.value != SBI_EXT_HSM_STARTED) {
+		report_fail("current hart is not started (ret.value=%ld)", ret.value);
+		report_prefix_popn(2);
+		return;
+	}
+
+	report_pass("status of current hart is started");
+
+	for_each_present_cpu(cpu) {
+		if (sbi_hart_get_status(cpus[cpu].hartid).error == SBI_ERR_INVALID_PARAM)
+			set_cpu_present(cpu, false);
+	}
+
+	report(cpumask_weight(&cpu_present_mask) == nr_cpus, "all present harts have valid hartids");
+
+	report_prefix_pop();
+
+	if (max_cpus < 2) {
+		report_skip("no other cpus to run the remaining hsm tests on");
+		report_prefix_pop();
+		return;
+	}
+
+	report_prefix_push("hart_start");
+
+	cpumask_copy(&secondary_cpus_mask, &cpu_present_mask);
+	cpumask_clear_cpu(me, &secondary_cpus_mask);
+	hsm_timer_setup();
+
+	cpumask_clear(&hsm_start);
+	cpumask_clear(&hsm_check);
+
+	for_each_cpu(cpu, &secondary_cpus_mask) {
+		hartid = cpus[cpu].hartid;
+		/* Set opaque as hartid so that we can check a0 == a1, ensuring that a0 is hartid and a1 is opaque */
+		ret = sbi_hart_start(hartid, virt_to_phys(&sbi_hsm_check_hart_start), hartid);
+		if (ret.error) {
+			report_fail("failed to start test hart %ld (error=%ld)", hartid, ret.error);
+			continue;
+		}
+
+		if (hart_wait_on_status(hartid, SBI_EXT_HSM_STOPPED, hsm_timer_duration))
+			continue;
+		if (hart_wait_on_status(hartid, SBI_EXT_HSM_START_PENDING, hsm_timer_duration))
+			continue;
+
+		ret = sbi_hart_get_status(hartid);
+		if (ret.error) {
+			report_info("hart %ld get status failed (error=%ld)", hartid, ret.error);
+			continue;
+		} else if (ret.value != SBI_EXT_HSM_STARTED) {
+			report_info("hart %ld status is not 'started' (ret.value=%ld)", hartid, ret.value);
+			continue;
+		} else {
+			cpumask_set_cpu(cpu, &hsm_start);
+		}
+
+		sbi_hsm_timer_fired = false;
+		timer_start(hsm_timer_duration);
+
+		while (!(READ_ONCE(sbi_hsm_hart_start_checks[cpu]) & SBI_HSM_TEST_DONE) && !sbi_hsm_timer_fired)
+			cpu_relax();
+
+		timer_stop();
+
+		if (sbi_hsm_timer_fired) {
+			report_info("hsm timer fired before hart %ld is done with start checks", hartid);
+			continue;
+		}
+
+		if (!(sbi_hsm_hart_start_checks[cpu] & SBI_HSM_TEST_SATP))
+			report_info("satp is not zero for test hart %ld", hartid);
+		else if (!(sbi_hsm_hart_start_checks[cpu] & SBI_HSM_TEST_SIE))
+			report_info("sstatus.SIE is not zero for test hart %ld", hartid);
+		else if (!(sbi_hsm_hart_start_checks[cpu] & SBI_HSM_TEST_HARTID_A1))
+			report_info("either a0 or a1 is not hartid for test hart %ld", hartid);
+		else
+			cpumask_set_cpu(cpu, &hsm_check);
+	}
+
+	report(cpumask_weight(&hsm_start) == max_cpus - 1, "all secondary harts started");
+	report(cpumask_weight(&hsm_check) == max_cpus - 1,
+	       "all secondary harts have expected register values after hart start");
+
+	report_prefix_pop();
+
+	report_prefix_push("hart_stop");
+
+	memset(sbi_hsm_stop_hart, 1, sizeof(sbi_hsm_stop_hart));
+
+	cpumask_clear(&hsm_stop);
+
+	for_each_cpu(cpu, &secondary_cpus_mask) {
+		hartid = cpus[cpu].hartid;
+		if (hart_wait_on_status(hartid, SBI_EXT_HSM_STARTED, hsm_timer_duration))
+			continue;
+		if (hart_wait_on_status(hartid, SBI_EXT_HSM_STOP_PENDING, hsm_timer_duration))
+			continue;
+
+		ret = sbi_hart_get_status(hartid);
+		if (ret.error)
+			report_info("hart %ld get status failed (error=%ld)", hartid, ret.error);
+		else if (ret.value != SBI_EXT_HSM_STOPPED)
+			report_info("hart %ld status is not 'stopped' (ret.value=%ld)", hartid, ret.value);
+		else
+			cpumask_set_cpu(cpu, &hsm_stop);
+	}
+
+	report(cpumask_weight(&hsm_stop) == max_cpus - 1, "all secondary harts stopped");
+
+	/* Reset the stop flags so that we can reuse them after suspension tests */
+	memset(sbi_hsm_stop_hart, 0, sizeof(sbi_hsm_stop_hart));
+
+	report_prefix_pop();
+
+	report_prefix_push("hart_start");
+
+	/* Select just one secondary cpu to run the invalid hartid test */
+	on_cpu(cpumask_next(-1, &secondary_cpus_mask), hart_start_invalid_hartid, NULL);
+
+	report(sbi_hsm_invalid_hartid_check, "secondary hart refuse to start with invalid hartid");
+
+	on_cpumask_async(&secondary_cpus_mask, hart_execute, NULL);
+
+	cpumask_clear(&hsm_start);
+
+	for_each_cpu(cpu, &secondary_cpus_mask) {
+		hartid = cpus[cpu].hartid;
+		if (hart_wait_on_status(hartid, SBI_EXT_HSM_STOPPED, hsm_timer_duration))
+			continue;
+		if (hart_wait_on_status(hartid, SBI_EXT_HSM_START_PENDING, hsm_timer_duration))
+			continue;
+
+		ret = sbi_hart_get_status(hartid);
+		if (ret.error)
+			report_info("hart %ld get status failed (error=%ld)", hartid, ret.error);
+		else if (ret.value != SBI_EXT_HSM_STARTED)
+			report_info("hart %ld status is not 'started' (ret.value=%ld)", hartid, ret.value);
+		else
+			cpumask_set_cpu(cpu, &hsm_start);
+	}
+
+	report(cpumask_weight(&hsm_start) == max_cpus - 1, "all secondary harts started");
+
+	sbi_hsm_timer_fired = false;
+	timer_start(hsm_timer_duration);
+
+	while (cpumask_weight(&cpu_idle_mask) != max_cpus - 1 && !sbi_hsm_timer_fired)
+		cpu_relax();
+
+	timer_stop();
+
+	if (sbi_hsm_timer_fired)
+		report_info("hsm timer fired before all secondary harts started");
+
+	report(cpumask_weight(&cpu_idle_mask) == max_cpus - 1,
+	       "all secondary harts successfully executed code after start");
+	report(cpumask_weight(&cpu_online_mask) == max_cpus, "all secondary harts online");
+	report(cpumask_weight(&sbi_hsm_started_hart_checks) == max_cpus - 1,
+	       "all secondary harts are already started");
+
+	report_prefix_pop();
+
+	report_prefix_push("hart_suspend");
+
+	if (!sbi_probe(SBI_EXT_IPI)) {
+		report_skip("skipping suspension tests since ipi extension is unavailable");
+		report_prefix_pop();
+		ipi_unavailable = true;
+		goto sbi_hsm_hart_stop_tests;
+	}
+
+	on_cpumask_async(&secondary_cpus_mask, hart_retentive_suspend, NULL);
+
+	cpumask_clear(&hsm_suspend);
+
+	for_each_cpu(cpu, &secondary_cpus_mask) {
+		hartid = cpus[cpu].hartid;
+		if (hart_wait_on_status(hartid, SBI_EXT_HSM_STARTED, hsm_timer_duration))
+			continue;
+		if (hart_wait_on_status(hartid, SBI_EXT_HSM_SUSPEND_PENDING, hsm_timer_duration))
+			continue;
+
+		ret = sbi_hart_get_status(hartid);
+		if (ret.error)
+			report_info("hart %ld get status failed (error=%ld)", hartid, ret.error);
+		else if (ret.value != SBI_EXT_HSM_SUSPENDED)
+			report_info("hart %ld status is not 'suspended' (ret.value=%ld)", hartid, ret.value);
+		else
+			cpumask_set_cpu(cpu, &hsm_suspend);
+	}
+
+	report(cpumask_weight(&hsm_suspend) == max_cpus - 1, "all secondary harts retentive suspended");
+
+	/* Ignore the return value since we check the status of each hart anyway */
+	sbi_send_ipi_cpumask(&secondary_cpus_mask);
+
+	cpumask_clear(&hsm_resume);
+
+	for_each_cpu(cpu, &secondary_cpus_mask) {
+		hartid = cpus[cpu].hartid;
+		if (hart_wait_on_status(hartid, SBI_EXT_HSM_SUSPENDED, hsm_timer_duration))
+			continue;
+		if (hart_wait_on_status(hartid, SBI_EXT_HSM_RESUME_PENDING, hsm_timer_duration))
+			continue;
+
+		ret = sbi_hart_get_status(hartid);
+		if (ret.error)
+			report_info("hart %ld get status failed (error=%ld)", hartid, ret.error);
+		else if (ret.value != SBI_EXT_HSM_STARTED)
+			report_info("hart %ld status is not 'started' (ret.value=%ld)", hartid, ret.value);
+		else
+			cpumask_set_cpu(cpu, &hsm_resume);
+	}
+
+	report(cpumask_weight(&hsm_resume) == max_cpus - 1, "all secondary harts retentive resumed");
+
+	sbi_hsm_timer_fired = false;
+	timer_start(hsm_timer_duration);
+
+	while (cpumask_weight(&cpu_idle_mask) != max_cpus - 1 && !sbi_hsm_timer_fired)
+		cpu_relax();
+
+	timer_stop();
+
+	if (sbi_hsm_timer_fired)
+		report_info("hsm timer fired before all secondary harts retentive resumed");
+
+	report(cpumask_weight(&cpu_idle_mask) == max_cpus - 1,
+	       "all secondary harts successfully executed code after retentive suspend");
+	report(cpumask_weight(&cpu_online_mask) == max_cpus,
+	       "all secondary harts online");
+
+	on_cpumask_async(&secondary_cpus_mask, hart_non_retentive_suspend, NULL);
+
+	cpumask_clear(&hsm_suspend);
+
+	for_each_cpu(cpu, &secondary_cpus_mask) {
+		hartid = cpus[cpu].hartid;
+		if (hart_wait_on_status(hartid, SBI_EXT_HSM_STARTED, hsm_timer_duration))
+			continue;
+		if (hart_wait_on_status(hartid, SBI_EXT_HSM_SUSPEND_PENDING, hsm_timer_duration))
+			continue;
+
+		ret = sbi_hart_get_status(hartid);
+		if (ret.error)
+			report_info("hart %ld get status failed (error=%ld)", hartid, ret.error);
+		else if (ret.value != SBI_EXT_HSM_SUSPENDED)
+			report_info("hart %ld status is not 'suspended' (ret.value=%ld)", hartid, ret.value);
+		else
+			cpumask_set_cpu(cpu, &hsm_suspend);
+	}
+
+	report(cpumask_weight(&hsm_suspend) == max_cpus - 1, "all secondary harts non-retentive suspended");
+
+	/* Ignore the return value since we check the status of each hart anyway */
+	sbi_send_ipi_cpumask(&secondary_cpus_mask);
+
+	cpumask_clear(&hsm_resume);
+	cpumask_clear(&hsm_check);
+
+	for_each_cpu(cpu, &secondary_cpus_mask) {
+		hartid = cpus[cpu].hartid;
+		if (hart_wait_on_status(hartid, SBI_EXT_HSM_SUSPENDED, hsm_timer_duration))
+			continue;
+		if (hart_wait_on_status(hartid, SBI_EXT_HSM_RESUME_PENDING, hsm_timer_duration))
+			continue;
+
+		ret = sbi_hart_get_status(hartid);
+		if (ret.error) {
+			report_info("hart %ld get status failed (error=%ld)", hartid, ret.error);
+			continue;
+		} else if (ret.value != SBI_EXT_HSM_STARTED) {
+			report_info("hart %ld status is not 'started' (ret.value=%ld)", hartid, ret.value);
+			continue;
+		} else {
+			cpumask_set_cpu(cpu, &hsm_resume);
+		}
+
+		sbi_hsm_timer_fired = false;
+		timer_start(hsm_timer_duration);
+
+		while (!((READ_ONCE(sbi_hsm_non_retentive_hart_suspend_checks[cpu])) & SBI_HSM_TEST_DONE)
+			&& !sbi_hsm_timer_fired)
+			cpu_relax();
+
+		timer_stop();
+
+		if (sbi_hsm_timer_fired) {
+			report_info("hsm timer fired before hart %ld is done with non-retentive resume checks",
+				    hartid);
+			continue;
+		}
+
+		if (!(sbi_hsm_non_retentive_hart_suspend_checks[cpu] & SBI_HSM_TEST_SATP))
+			report_info("satp is not zero for test hart %ld", hartid);
+		else if (!(sbi_hsm_non_retentive_hart_suspend_checks[cpu] & SBI_HSM_TEST_SIE))
+			report_info("sstatus.SIE is not zero for test hart %ld", hartid);
+		else if (!(sbi_hsm_non_retentive_hart_suspend_checks[cpu] & SBI_HSM_TEST_HARTID_A1))
+			report_info("either a0 or a1 is not hartid for test hart %ld", hartid);
+		else
+			cpumask_set_cpu(cpu, &hsm_check);
+	}
+
+	report(cpumask_weight(&hsm_resume) == max_cpus - 1, "all secondary harts non-retentive resumed");
+	report(cpumask_weight(&hsm_check) == max_cpus - 1,
+	       "all secondary harts have expected register values after non-retentive resume");
+
+	report_prefix_pop();
+
+sbi_hsm_hart_stop_tests:
+	report_prefix_push("hart_stop");
+
+	if (ipi_unavailable)
+		on_cpumask_async(&secondary_cpus_mask, hart_stop, NULL);
+	else
+		memset(sbi_hsm_stop_hart, 1, sizeof(sbi_hsm_stop_hart));
+
+	cpumask_clear(&hsm_stop);
+
+	for_each_cpu(cpu, &secondary_cpus_mask) {
+		hartid = cpus[cpu].hartid;
+		if (hart_wait_on_status(hartid, SBI_EXT_HSM_STARTED, hsm_timer_duration))
+			continue;
+		if (hart_wait_on_status(hartid, SBI_EXT_HSM_STOP_PENDING, hsm_timer_duration))
+			continue;
+
+		ret = sbi_hart_get_status(hartid);
+		if (ret.error)
+			report_info("hart %ld get status failed (error=%ld)", hartid, ret.error);
+		else if (ret.value != SBI_EXT_HSM_STOPPED)
+			report_info("hart %ld status is not 'stopped' (ret.value=%ld)", hartid, ret.value);
+		else
+			cpumask_set_cpu(cpu, &hsm_stop);
+	}
+
+	report(cpumask_weight(&hsm_stop) == max_cpus - 1, "all secondary harts stopped");
+
+	/* Reset the state of the secondary cpus since they did not have a chance to clean up after stopping */
+	for_each_cpu(cpu, &secondary_cpus_mask) {
+		on_cpu_clear_func(cpu);
+		set_cpu_online(cpu, false);
+		set_cpu_started(cpu, false);
+	}
+
+	if (__riscv_xlen == 32 || ipi_unavailable) {
+		hsm_timer_teardown();
+		report_prefix_popn(2);
+		return;
+	}
+
+	report_prefix_pop();
+
+	report_prefix_push("hart_suspend");
+
+	/* Select just one secondary cpu to run suspension tests with MSB of suspend type being set */
+	cpu = cpumask_next(-1, &secondary_cpus_mask);
+	hartid = cpus[cpu].hartid;
+
+	/* Boot up the secondary cpu and let it proceed to the idle loop */
+	on_cpu(cpu, hart_empty_fn, NULL);
+
+	on_cpu_async(cpu, hart_retentive_suspend_with_msb_set, NULL);
+
+	if (!hart_wait_on_status(hartid, SBI_EXT_HSM_STARTED, hsm_timer_duration) &&
+	    !hart_wait_on_status(hartid, SBI_EXT_HSM_SUSPEND_PENDING, hsm_timer_duration)) {
+		ret = sbi_hart_get_status(hartid);
+		if (ret.error)
+			report_info("hart %ld get status failed (error=%ld)", hartid, ret.error);
+		else if (ret.value != SBI_EXT_HSM_SUSPENDED)
+			report_info("hart %ld status is not 'suspended' (ret.value=%ld)", hartid, ret.value);
+		else
+			suspend_with_msb = true;
+	}
+
+	report(suspend_with_msb, "secondary hart retentive suspended with MSB set");
+
+	/* Ignore the return value since we manually validate the status of the hart anyway */
+	sbi_send_ipi_cpu(cpu);
+
+	if (!hart_wait_on_status(hartid, SBI_EXT_HSM_SUSPENDED, hsm_timer_duration) &&
+	    !hart_wait_on_status(hartid, SBI_EXT_HSM_RESUME_PENDING, hsm_timer_duration)) {
+		ret = sbi_hart_get_status(hartid);
+		if (ret.error)
+			report_info("hart %ld get status failed (error=%ld)", hartid, ret.error);
+		else if (ret.value != SBI_EXT_HSM_STARTED)
+			report_info("hart %ld status is not 'started' (ret.value=%ld)", hartid, ret.value);
+		else
+			resume_with_msb = true;
+	}
+
+	report(resume_with_msb, "secondary hart retentive resumed with MSB set");
+
+	/* Reset these flags so that we can reuse them for the non-retentive suspension test */
+	suspend_with_msb = false;
+	resume_with_msb = false;
+	sbi_hsm_stop_hart[cpu] = 0;
+	sbi_hsm_non_retentive_hart_suspend_checks[cpu] = 0;
+
+	on_cpu_async(cpu, hart_non_retentive_suspend_with_msb_set, NULL);
+
+	if (!hart_wait_on_status(hartid, SBI_EXT_HSM_STARTED, hsm_timer_duration) &&
+	    !hart_wait_on_status(hartid, SBI_EXT_HSM_SUSPEND_PENDING, hsm_timer_duration)) {
+		ret = sbi_hart_get_status(hartid);
+		if (ret.error)
+			report_info("hart %ld get status failed (error=%ld)", hartid, ret.error);
+		else if (ret.value != SBI_EXT_HSM_SUSPENDED)
+			report_info("hart %ld status is not 'suspended' (ret.value=%ld)", hartid, ret.value);
+		else
+			suspend_with_msb = true;
+	}
+
+	report(suspend_with_msb, "secondary hart non-retentive suspended with MSB set");
+
+	/* Ignore the return value since we manually validate the status of the hart anyway */
+	sbi_send_ipi_cpu(cpu);
+
+	if (!hart_wait_on_status(hartid, SBI_EXT_HSM_SUSPENDED, hsm_timer_duration) &&
+	    !hart_wait_on_status(hartid, SBI_EXT_HSM_RESUME_PENDING, hsm_timer_duration)) {
+		ret = sbi_hart_get_status(hartid);
+		if (ret.error)
+			report_info("hart %ld get status failed (error=%ld)", hartid, ret.error);
+		else if (ret.value != SBI_EXT_HSM_STARTED)
+			report_info("hart %ld status is not 'started' (ret.value=%ld)", hartid, ret.value);
+		else
+			resume_with_msb = true;
+
+		sbi_hsm_timer_fired = false;
+		timer_start(hsm_timer_duration);
+
+		while (!((READ_ONCE(sbi_hsm_non_retentive_hart_suspend_checks[cpu])) & SBI_HSM_TEST_DONE)
+			&& !sbi_hsm_timer_fired)
+			cpu_relax();
+
+		timer_stop();
+
+		if (sbi_hsm_timer_fired) {
+			report_info("hsm timer fired before hart %ld is done with non-retentive resume checks",
+				    hartid);
+		} else {
+			if (!(sbi_hsm_non_retentive_hart_suspend_checks[cpu] & SBI_HSM_TEST_SATP))
+				report_info("satp is not zero for test hart %ld", hartid);
+			else if (!(sbi_hsm_non_retentive_hart_suspend_checks[cpu] & SBI_HSM_TEST_SIE))
+				report_info("sstatus.SIE is not zero for test hart %ld", hartid);
+			else if (!(sbi_hsm_non_retentive_hart_suspend_checks[cpu] & SBI_HSM_TEST_HARTID_A1))
+				report_info("either a0 or a1 is not hartid for test hart %ld", hartid);
+			else
+				check_with_msb = true;
+		}
+	}
+
+	report(resume_with_msb, "secondary hart non-retentive resumed with MSB set");
+	report(check_with_msb,
+	       "secondary hart has expected register values after non-retentive resume with MSB set");
+
+	report_prefix_pop();
+
+	report_prefix_push("hart_stop");
+
+	sbi_hsm_stop_hart[cpu] = 1;
+
+	if (!hart_wait_on_status(hartid, SBI_EXT_HSM_STARTED, hsm_timer_duration) &&
+	    !hart_wait_on_status(hartid, SBI_EXT_HSM_STOP_PENDING, hsm_timer_duration)) {
+		ret = sbi_hart_get_status(hartid);
+		if (ret.error)
+			report_info("hart %ld get status failed (error=%ld)", hartid, ret.error);
+		else if (ret.value != SBI_EXT_HSM_STOPPED)
+			report_info("hart %ld status is not 'stopped' (ret.value=%ld)", hartid, ret.value);
+		else
+			stop_with_msb = true;
+	}
+
+	report(stop_with_msb, "secondary hart stopped after suspension tests with MSB set");
+
+	/* Reset the state of the secondary cpu since it did not have a chance to clean up after stopping */
+	on_cpu_clear_func(cpu);
+	set_cpu_online(cpu, false);
+	set_cpu_started(cpu, false);
+
+	hsm_timer_teardown();
+	report_prefix_popn(2);
+}
 
 int main(int argc, char **argv)
 {
@@ -444,6 +1091,7 @@ int main(int argc, char **argv)
 	report_prefix_push("sbi");
 	check_base();
 	check_time();
+	check_hsm();
 	check_dbcn();
 
 	return report_summary();
-- 
2.43.0