Skip to content

Commit d0b94bc

Browse files
xiaobo55xavpatel
xiaobo55x
authored and
avpatel
committed
KVM: riscv: selftests: Add sstc timer test
Add a KVM selftests to validate the Sstc timer functionality. The test was ported from arm64 arch timer test. Signed-off-by: Haibo Xu <haibo1.xu@intel.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Signed-off-by: Anup Patel <anup@brainfault.org>
1 parent 812806b commit d0b94bc

7 files changed

Lines changed: 210 additions & 10 deletions

File tree

‎tools/testing/selftests/kvm/Makefile‎

Lines changed: 1 addition & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -185,6 +185,7 @@ TEST_GEN_PROGS_s390x += rseq_test
185185
TEST_GEN_PROGS_s390x += set_memory_region_test
186186
TEST_GEN_PROGS_s390x += kvm_binary_stats_test
187187

188+
TEST_GEN_PROGS_riscv += arch_timer
188189
TEST_GEN_PROGS_riscv += demand_paging_test
189190
TEST_GEN_PROGS_riscv += dirty_log_test
190191
TEST_GEN_PROGS_riscv += get-reg-list

‎tools/testing/selftests/kvm/aarch64/arch_timer.c‎

Lines changed: 8 additions & 4 deletions
Original file line numberDiff line numberDiff line change
@@ -194,10 +194,14 @@ struct kvm_vm *test_vm_create(void)
194194
vm_init_descriptor_tables(vm);
195195
vm_install_exception_handler(vm, VECTOR_IRQ_CURRENT, guest_irq_handler);
196196

197-
if (!test_args.offset.reserved) {
198-
if (kvm_has_cap(KVM_CAP_COUNTER_OFFSET))
199-
vm_ioctl(vm, KVM_ARM_SET_COUNTER_OFFSET, &test_args.offset);
200-
else
197+
if (!test_args.reserved) {
198+
if (kvm_has_cap(KVM_CAP_COUNTER_OFFSET)) {
199+
struct kvm_arm_counter_offset offset = {
200+
.counter_offset = test_args.counter_offset,
201+
.reserved = 0,
202+
};
203+
vm_ioctl(vm, KVM_ARM_SET_COUNTER_OFFSET, &offset);
204+
} else
201205
TEST_FAIL("no support for global offset");
202206
}
203207

‎tools/testing/selftests/kvm/arch_timer.c‎

Lines changed: 6 additions & 4 deletions
Original file line numberDiff line numberDiff line change
@@ -36,7 +36,7 @@ struct test_args test_args = {
3636
.timer_period_ms = TIMER_TEST_PERIOD_MS_DEF,
3737
.migration_freq_ms = TIMER_TEST_MIGRATION_FREQ_MS,
3838
.timer_err_margin_us = TIMER_TEST_ERR_MARGIN_US,
39-
.offset = { .reserved = 1 },
39+
.reserved = 1,
4040
};
4141

4242
struct kvm_vcpu *vcpus[KVM_MAX_VCPUS];
@@ -75,6 +75,8 @@ static void *test_vcpu_run(void *arg)
7575
TEST_FAIL("Unexpected guest exit");
7676
}
7777

78+
pr_info("PASS(vCPU-%d).\n", vcpu_idx);
79+
7880
return NULL;
7981
}
8082

@@ -190,7 +192,7 @@ static void test_print_help(char *name)
190192
TIMER_TEST_PERIOD_MS_DEF);
191193
pr_info("\t-m: Frequency (in ms) of vCPUs to migrate to different pCPU. 0 to turn off (default: %u)\n",
192194
TIMER_TEST_MIGRATION_FREQ_MS);
193-
pr_info("\t-o: Counter offset (in counter cycles, default: 0)\n");
195+
pr_info("\t-o: Counter offset (in counter cycles, default: 0) [aarch64-only]\n");
194196
pr_info("\t-e: Interrupt arrival error margin (in us) of the guest timer (default: %u)\n",
195197
TIMER_TEST_ERR_MARGIN_US);
196198
pr_info("\t-h: print this help screen\n");
@@ -223,8 +225,8 @@ static bool parse_args(int argc, char *argv[])
223225
test_args.timer_err_margin_us = atoi_non_negative("Error Margin", optarg);
224226
break;
225227
case 'o':
226-
test_args.offset.counter_offset = strtol(optarg, NULL, 0);
227-
test_args.offset.reserved = 0;
228+
test_args.counter_offset = strtol(optarg, NULL, 0);
229+
test_args.reserved = 0;
228230
break;
229231
case 'h':
230232
default:

‎tools/testing/selftests/kvm/include/riscv/arch_timer.h‎

Lines changed: 71 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,71 @@
1+
/* SPDX-License-Identifier: GPL-2.0 */
2+
/*
3+
* RISC-V Arch Timer(sstc) specific interface
4+
*
5+
* Copyright (c) 2024 Intel Corporation
6+
*/
7+
8+
#ifndef SELFTEST_KVM_ARCH_TIMER_H
9+
#define SELFTEST_KVM_ARCH_TIMER_H
10+
11+
#include <asm/csr.h>
12+
#include <asm/vdso/processor.h>
13+
14+
static unsigned long timer_freq;
15+
16+
#define msec_to_cycles(msec) \
17+
((timer_freq) * (uint64_t)(msec) / 1000)
18+
19+
#define usec_to_cycles(usec) \
20+
((timer_freq) * (uint64_t)(usec) / 1000000)
21+
22+
#define cycles_to_usec(cycles) \
23+
((uint64_t)(cycles) * 1000000 / (timer_freq))
24+
25+
static inline uint64_t timer_get_cycles(void)
26+
{
27+
return csr_read(CSR_TIME);
28+
}
29+
30+
static inline void timer_set_cmp(uint64_t cval)
31+
{
32+
csr_write(CSR_STIMECMP, cval);
33+
}
34+
35+
static inline uint64_t timer_get_cmp(void)
36+
{
37+
return csr_read(CSR_STIMECMP);
38+
}
39+
40+
static inline void timer_irq_enable(void)
41+
{
42+
csr_set(CSR_SIE, IE_TIE);
43+
}
44+
45+
static inline void timer_irq_disable(void)
46+
{
47+
csr_clear(CSR_SIE, IE_TIE);
48+
}
49+
50+
static inline void timer_set_next_cmp_ms(uint32_t msec)
51+
{
52+
uint64_t now_ct = timer_get_cycles();
53+
uint64_t next_ct = now_ct + msec_to_cycles(msec);
54+
55+
timer_set_cmp(next_ct);
56+
}
57+
58+
static inline void __delay(uint64_t cycles)
59+
{
60+
uint64_t start = timer_get_cycles();
61+
62+
while ((timer_get_cycles() - start) < cycles)
63+
cpu_relax();
64+
}
65+
66+
static inline void udelay(unsigned long usec)
67+
{
68+
__delay(usec_to_cycles(usec));
69+
}
70+
71+
#endif /* SELFTEST_KVM_ARCH_TIMER_H */

‎tools/testing/selftests/kvm/include/riscv/processor.h‎

Lines changed: 10 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -193,4 +193,14 @@ struct sbiret sbi_ecall(int ext, int fid, unsigned long arg0,
193193

194194
bool guest_sbi_probe_extension(int extid, long *out_val);
195195

196+
static inline void local_irq_enable(void)
197+
{
198+
csr_set(CSR_SSTATUS, SR_SIE);
199+
}
200+
201+
static inline void local_irq_disable(void)
202+
{
203+
csr_clear(CSR_SSTATUS, SR_SIE);
204+
}
205+
196206
#endif /* SELFTEST_KVM_PROCESSOR_H */

‎tools/testing/selftests/kvm/include/timer_test.h‎

Lines changed: 3 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -23,8 +23,9 @@ struct test_args {
2323
uint32_t timer_period_ms;
2424
uint32_t migration_freq_ms;
2525
uint32_t timer_err_margin_us;
26-
/* TODO: Change arm specific type to a common one */
27-
struct kvm_arm_counter_offset offset;
26+
/* Members of struct kvm_arm_counter_offset */
27+
uint64_t counter_offset;
28+
uint64_t reserved;
2829
};
2930

3031
/* Shared variables between host and guest */

‎tools/testing/selftests/kvm/riscv/arch_timer.c‎

Lines changed: 111 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,111 @@
1+
// SPDX-License-Identifier: GPL-2.0-only
2+
/*
3+
* arch_timer.c - Tests the riscv64 sstc timer IRQ functionality
4+
*
5+
* The test validates the sstc timer IRQs using vstimecmp registers.
6+
* It's ported from the aarch64 arch_timer test.
7+
*
8+
* Copyright (c) 2024, Intel Corporation.
9+
*/
10+
11+
#define _GNU_SOURCE
12+
13+
#include "arch_timer.h"
14+
#include "kvm_util.h"
15+
#include "processor.h"
16+
#include "timer_test.h"
17+
18+
static int timer_irq = IRQ_S_TIMER;
19+
20+
static void guest_irq_handler(struct ex_regs *regs)
21+
{
22+
uint64_t xcnt, xcnt_diff_us, cmp;
23+
unsigned int intid = regs->cause & ~CAUSE_IRQ_FLAG;
24+
uint32_t cpu = guest_get_vcpuid();
25+
struct test_vcpu_shared_data *shared_data = &vcpu_shared_data[cpu];
26+
27+
timer_irq_disable();
28+
29+
xcnt = timer_get_cycles();
30+
cmp = timer_get_cmp();
31+
xcnt_diff_us = cycles_to_usec(xcnt - shared_data->xcnt);
32+
33+
/* Make sure we are dealing with the correct timer IRQ */
34+
GUEST_ASSERT_EQ(intid, timer_irq);
35+
36+
__GUEST_ASSERT(xcnt >= cmp,
37+
"xcnt = 0x%"PRIx64", cmp = 0x%"PRIx64", xcnt_diff_us = 0x%" PRIx64,
38+
xcnt, cmp, xcnt_diff_us);
39+
40+
WRITE_ONCE(shared_data->nr_iter, shared_data->nr_iter + 1);
41+
}
42+
43+
static void guest_run(struct test_vcpu_shared_data *shared_data)
44+
{
45+
uint32_t irq_iter, config_iter;
46+
47+
shared_data->nr_iter = 0;
48+
shared_data->guest_stage = 0;
49+
50+
for (config_iter = 0; config_iter < test_args.nr_iter; config_iter++) {
51+
/* Setup the next interrupt */
52+
timer_set_next_cmp_ms(test_args.timer_period_ms);
53+
shared_data->xcnt = timer_get_cycles();
54+
timer_irq_enable();
55+
56+
/* Setup a timeout for the interrupt to arrive */
57+
udelay(msecs_to_usecs(test_args.timer_period_ms) +
58+
test_args.timer_err_margin_us);
59+
60+
irq_iter = READ_ONCE(shared_data->nr_iter);
61+
__GUEST_ASSERT(config_iter + 1 == irq_iter,
62+
"config_iter + 1 = 0x%x, irq_iter = 0x%x.\n"
63+
" Guest timer interrupt was not trigged within the specified\n"
64+
" interval, try to increase the error margin by [-e] option.\n",
65+
config_iter + 1, irq_iter);
66+
}
67+
}
68+
69+
static void guest_code(void)
70+
{
71+
uint32_t cpu = guest_get_vcpuid();
72+
struct test_vcpu_shared_data *shared_data = &vcpu_shared_data[cpu];
73+
74+
timer_irq_disable();
75+
local_irq_enable();
76+
77+
guest_run(shared_data);
78+
79+
GUEST_DONE();
80+
}
81+
82+
struct kvm_vm *test_vm_create(void)
83+
{
84+
struct kvm_vm *vm;
85+
int nr_vcpus = test_args.nr_vcpus;
86+
87+
vm = vm_create_with_vcpus(nr_vcpus, guest_code, vcpus);
88+
__TEST_REQUIRE(__vcpu_has_ext(vcpus[0], RISCV_ISA_EXT_REG(KVM_RISCV_ISA_EXT_SSTC)),
89+
"SSTC not available, skipping test\n");
90+
91+
vm_init_vector_tables(vm);
92+
vm_install_interrupt_handler(vm, guest_irq_handler);
93+
94+
for (int i = 0; i < nr_vcpus; i++)
95+
vcpu_init_vector_tables(vcpus[i]);
96+
97+
/* Initialize guest timer frequency. */
98+
vcpu_get_reg(vcpus[0], RISCV_TIMER_REG(frequency), &timer_freq);
99+
sync_global_to_guest(vm, timer_freq);
100+
pr_debug("timer_freq: %lu\n", timer_freq);
101+
102+
/* Make all the test's cmdline args visible to the guest */
103+
sync_global_to_guest(vm, test_args);
104+
105+
return vm;
106+
}
107+
108+
void test_vm_cleanup(struct kvm_vm *vm)
109+
{
110+
kvm_vm_free(vm);
111+
}

0 commit comments

Comments
 (0)