1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (c) 2023 Rivos Inc
4 *
5 * Authors:
6 * Atish Patra <atishp@rivosinc.com>
7 */
8
9 #include <linux/errno.h>
10 #include <linux/err.h>
11 #include <linux/kvm_host.h>
12 #include <asm/csr.h>
13 #include <asm/sbi.h>
14 #include <asm/kvm_vcpu_sbi.h>
15
kvm_sbi_ext_pmu_handler(struct kvm_vcpu * vcpu,struct kvm_run * run,struct kvm_vcpu_sbi_return * retdata)16 static int kvm_sbi_ext_pmu_handler(struct kvm_vcpu *vcpu, struct kvm_run *run,
17 struct kvm_vcpu_sbi_return *retdata)
18 {
19 int ret = 0;
20 struct kvm_cpu_context *cp = &vcpu->arch.guest_context;
21 struct kvm_pmu *kvpmu = vcpu_to_pmu(vcpu);
22 unsigned long funcid = cp->a6;
23 u64 temp;
24
25 if (!kvpmu->init_done) {
26 retdata->err_val = SBI_ERR_NOT_SUPPORTED;
27 return 0;
28 }
29
30 switch (funcid) {
31 case SBI_EXT_PMU_NUM_COUNTERS:
32 ret = kvm_riscv_vcpu_pmu_num_ctrs(vcpu, retdata);
33 break;
34 case SBI_EXT_PMU_COUNTER_GET_INFO:
35 ret = kvm_riscv_vcpu_pmu_ctr_info(vcpu, cp->a0, retdata);
36 break;
37 case SBI_EXT_PMU_COUNTER_CFG_MATCH:
38 #if defined(CONFIG_32BIT)
39 temp = ((uint64_t)cp->a5 << 32) | cp->a4;
40 #else
41 temp = cp->a4;
42 #endif
43 /*
44 * This can fail if perf core framework fails to create an event.
45 * No need to forward the error to userspace and exit the guest.
46 * The operation can continue without profiling. Forward the
47 * appropriate SBI error to the guest.
48 */
49 ret = kvm_riscv_vcpu_pmu_ctr_cfg_match(vcpu, cp->a0, cp->a1,
50 cp->a2, cp->a3, temp, retdata);
51 break;
52 case SBI_EXT_PMU_COUNTER_START:
53 #if defined(CONFIG_32BIT)
54 temp = ((uint64_t)cp->a4 << 32) | cp->a3;
55 #else
56 temp = cp->a3;
57 #endif
58 ret = kvm_riscv_vcpu_pmu_ctr_start(vcpu, cp->a0, cp->a1, cp->a2,
59 temp, retdata);
60 break;
61 case SBI_EXT_PMU_COUNTER_STOP:
62 ret = kvm_riscv_vcpu_pmu_ctr_stop(vcpu, cp->a0, cp->a1, cp->a2, retdata);
63 break;
64 case SBI_EXT_PMU_COUNTER_FW_READ:
65 ret = kvm_riscv_vcpu_pmu_fw_ctr_read(vcpu, cp->a0, retdata);
66 break;
67 case SBI_EXT_PMU_COUNTER_FW_READ_HI:
68 if (IS_ENABLED(CONFIG_32BIT))
69 ret = kvm_riscv_vcpu_pmu_fw_ctr_read_hi(vcpu, cp->a0, retdata);
70 else
71 retdata->out_val = 0;
72 break;
73 case SBI_EXT_PMU_SNAPSHOT_SET_SHMEM:
74 ret = kvm_riscv_vcpu_pmu_snapshot_set_shmem(vcpu, cp->a0, cp->a1, cp->a2, retdata);
75 break;
76 default:
77 retdata->err_val = SBI_ERR_NOT_SUPPORTED;
78 }
79
80 return ret;
81 }
82
kvm_sbi_ext_pmu_probe(struct kvm_vcpu * vcpu)83 static unsigned long kvm_sbi_ext_pmu_probe(struct kvm_vcpu *vcpu)
84 {
85 struct kvm_pmu *kvpmu = vcpu_to_pmu(vcpu);
86
87 return kvpmu->init_done;
88 }
89
90 const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_pmu = {
91 .extid_start = SBI_EXT_PMU,
92 .extid_end = SBI_EXT_PMU,
93 .handler = kvm_sbi_ext_pmu_handler,
94 .probe = kvm_sbi_ext_pmu_probe,
95 };
96