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