1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Copyright (c) 2021 Western Digital Corporation or its affiliates.
  4 *
  5 * Authors:
  6 *     Atish Patra <atish.patra@wdc.com>
  7 */
  8
  9#include <linux/errno.h>
 10#include <linux/err.h>
 11#include <linux/kvm_host.h>
 12#include <asm/sbi.h>
 13#include <asm/kvm_vcpu_timer.h>
 14#include <asm/kvm_vcpu_pmu.h>
 15#include <asm/kvm_vcpu_sbi.h>
 16
 17static int kvm_sbi_ext_time_handler(struct kvm_vcpu *vcpu, struct kvm_run *run,
 18				    struct kvm_vcpu_sbi_return *retdata)
 19{
 20	struct kvm_cpu_context *cp = &vcpu->arch.guest_context;
 21	u64 next_cycle;
 22
 23	if (cp->a6 != SBI_EXT_TIME_SET_TIMER) {
 24		retdata->err_val = SBI_ERR_NOT_SUPPORTED;
 25		return 0;
 26	}
 27
 28	kvm_riscv_vcpu_pmu_incr_fw(vcpu, SBI_PMU_FW_SET_TIMER);
 29#if __riscv_xlen == 32
 30	next_cycle = ((u64)cp->a1 << 32) | (u64)cp->a0;
 31#else
 32	next_cycle = (u64)cp->a0;
 33#endif
 34	kvm_riscv_vcpu_timer_next_event(vcpu, next_cycle);
 35
 36	return 0;
 37}
 38
 39const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_time = {
 40	.extid_start = SBI_EXT_TIME,
 41	.extid_end = SBI_EXT_TIME,
 42	.handler = kvm_sbi_ext_time_handler,
 43};
 44
 45static int kvm_sbi_ext_ipi_handler(struct kvm_vcpu *vcpu, struct kvm_run *run,
 46				   struct kvm_vcpu_sbi_return *retdata)
 47{
 48	int ret = 0;
 49	unsigned long i;
 50	struct kvm_vcpu *tmp;
 51	struct kvm_cpu_context *cp = &vcpu->arch.guest_context;
 52	unsigned long hmask = cp->a0;
 53	unsigned long hbase = cp->a1;
 54	unsigned long hart_bit = 0, sentmask = 0;
 55
 56	if (cp->a6 != SBI_EXT_IPI_SEND_IPI) {
 57		retdata->err_val = SBI_ERR_NOT_SUPPORTED;
 58		return 0;
 59	}
 60
 61	kvm_riscv_vcpu_pmu_incr_fw(vcpu, SBI_PMU_FW_IPI_SENT);
 62	kvm_for_each_vcpu(i, tmp, vcpu->kvm) {
 63		if (hbase != -1UL) {
 64			if (tmp->vcpu_id < hbase)
 65				continue;
 66			hart_bit = tmp->vcpu_id - hbase;
 67			if (hart_bit >= __riscv_xlen)
 68				goto done;
 69			if (!(hmask & (1UL << hart_bit)))
 70				continue;
 71		}
 72		ret = kvm_riscv_vcpu_set_interrupt(tmp, IRQ_VS_SOFT);
 73		if (ret < 0)
 74			break;
 75		sentmask |= 1UL << hart_bit;
 76		kvm_riscv_vcpu_pmu_incr_fw(tmp, SBI_PMU_FW_IPI_RCVD);
 77	}
 78
 79done:
 80	if (hbase != -1UL && (hmask ^ sentmask))
 81		retdata->err_val = SBI_ERR_INVALID_PARAM;
 82
 83	return ret;
 84}
 85
 86const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_ipi = {
 87	.extid_start = SBI_EXT_IPI,
 88	.extid_end = SBI_EXT_IPI,
 89	.handler = kvm_sbi_ext_ipi_handler,
 90};
 91
 92static int kvm_sbi_ext_rfence_handler(struct kvm_vcpu *vcpu, struct kvm_run *run,
 93				      struct kvm_vcpu_sbi_return *retdata)
 94{
 95	struct kvm_cpu_context *cp = &vcpu->arch.guest_context;
 96	unsigned long hmask = cp->a0;
 97	unsigned long hbase = cp->a1;
 98	unsigned long funcid = cp->a6;
 99
100	switch (funcid) {
101	case SBI_EXT_RFENCE_REMOTE_FENCE_I:
102		kvm_riscv_fence_i(vcpu->kvm, hbase, hmask);
103		kvm_riscv_vcpu_pmu_incr_fw(vcpu, SBI_PMU_FW_FENCE_I_SENT);
104		break;
105	case SBI_EXT_RFENCE_REMOTE_SFENCE_VMA:
106		if (cp->a2 == 0 && cp->a3 == 0)
107			kvm_riscv_hfence_vvma_all(vcpu->kvm, hbase, hmask);
108		else
109			kvm_riscv_hfence_vvma_gva(vcpu->kvm, hbase, hmask,
110						  cp->a2, cp->a3, PAGE_SHIFT);
111		kvm_riscv_vcpu_pmu_incr_fw(vcpu, SBI_PMU_FW_HFENCE_VVMA_SENT);
112		break;
113	case SBI_EXT_RFENCE_REMOTE_SFENCE_VMA_ASID:
114		if (cp->a2 == 0 && cp->a3 == 0)
115			kvm_riscv_hfence_vvma_asid_all(vcpu->kvm,
116						       hbase, hmask, cp->a4);
117		else
118			kvm_riscv_hfence_vvma_asid_gva(vcpu->kvm,
119						       hbase, hmask,
120						       cp->a2, cp->a3,
121						       PAGE_SHIFT, cp->a4);
122		kvm_riscv_vcpu_pmu_incr_fw(vcpu, SBI_PMU_FW_HFENCE_VVMA_ASID_SENT);
123		break;
124	case SBI_EXT_RFENCE_REMOTE_HFENCE_GVMA:
125	case SBI_EXT_RFENCE_REMOTE_HFENCE_GVMA_VMID:
126	case SBI_EXT_RFENCE_REMOTE_HFENCE_VVMA:
127	case SBI_EXT_RFENCE_REMOTE_HFENCE_VVMA_ASID:
128		/*
129		 * Until nested virtualization is implemented, the
130		 * SBI HFENCE calls should be treated as NOPs
131		 */
132		break;
133	default:
134		retdata->err_val = SBI_ERR_NOT_SUPPORTED;
135	}
136
137	return 0;
138}
139
140const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_rfence = {
141	.extid_start = SBI_EXT_RFENCE,
142	.extid_end = SBI_EXT_RFENCE,
143	.handler = kvm_sbi_ext_rfence_handler,
144};
145
146static int kvm_sbi_ext_srst_handler(struct kvm_vcpu *vcpu,
147				    struct kvm_run *run,
148				    struct kvm_vcpu_sbi_return *retdata)
149{
150	struct kvm_cpu_context *cp = &vcpu->arch.guest_context;
151	unsigned long funcid = cp->a6;
152	u32 reason = cp->a1;
153	u32 type = cp->a0;
154
155	switch (funcid) {
156	case SBI_EXT_SRST_RESET:
157		switch (type) {
158		case SBI_SRST_RESET_TYPE_SHUTDOWN:
159			kvm_riscv_vcpu_sbi_system_reset(vcpu, run,
160						KVM_SYSTEM_EVENT_SHUTDOWN,
161						reason);
162			retdata->uexit = true;
163			break;
164		case SBI_SRST_RESET_TYPE_COLD_REBOOT:
165		case SBI_SRST_RESET_TYPE_WARM_REBOOT:
166			kvm_riscv_vcpu_sbi_system_reset(vcpu, run,
167						KVM_SYSTEM_EVENT_RESET,
168						reason);
169			retdata->uexit = true;
170			break;
171		default:
172			retdata->err_val = SBI_ERR_NOT_SUPPORTED;
173		}
174		break;
175	default:
176		retdata->err_val = SBI_ERR_NOT_SUPPORTED;
177	}
178
179	return 0;
180}
181
182const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_srst = {
183	.extid_start = SBI_EXT_SRST,
184	.extid_end = SBI_EXT_SRST,
185	.handler = kvm_sbi_ext_srst_handler,
186};
187
188static int kvm_sbi_ext_dbcn_handler(struct kvm_vcpu *vcpu,
189				    struct kvm_run *run,
190				    struct kvm_vcpu_sbi_return *retdata)
191{
192	struct kvm_cpu_context *cp = &vcpu->arch.guest_context;
193	unsigned long funcid = cp->a6;
194
195	switch (funcid) {
196	case SBI_EXT_DBCN_CONSOLE_WRITE:
197	case SBI_EXT_DBCN_CONSOLE_READ:
198	case SBI_EXT_DBCN_CONSOLE_WRITE_BYTE:
199		/*
200		 * The SBI debug console functions are unconditionally
201		 * forwarded to the userspace.
202		 */
203		kvm_riscv_vcpu_sbi_forward(vcpu, run);
204		retdata->uexit = true;
205		break;
206	default:
207		retdata->err_val = SBI_ERR_NOT_SUPPORTED;
208	}
209
210	return 0;
211}
212
213const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_dbcn = {
214	.extid_start = SBI_EXT_DBCN,
215	.extid_end = SBI_EXT_DBCN,
216	.default_disabled = true,
217	.handler = kvm_sbi_ext_dbcn_handler,
218};