1*4882a593Smuzhiyun /*
2*4882a593Smuzhiyun * This file is subject to the terms and conditions of the GNU General Public
3*4882a593Smuzhiyun * License. See the file "COPYING" in the main directory of this archive
4*4882a593Smuzhiyun * for more details.
5*4882a593Smuzhiyun *
6*4882a593Smuzhiyun * KVM/MIPS: Hypercall handling.
7*4882a593Smuzhiyun *
8*4882a593Smuzhiyun * Copyright (C) 2015 Imagination Technologies Ltd.
9*4882a593Smuzhiyun */
10*4882a593Smuzhiyun
11*4882a593Smuzhiyun #include <linux/kernel.h>
12*4882a593Smuzhiyun #include <linux/kvm_host.h>
13*4882a593Smuzhiyun #include <linux/kvm_para.h>
14*4882a593Smuzhiyun
15*4882a593Smuzhiyun #define MAX_HYPCALL_ARGS 4
16*4882a593Smuzhiyun
kvm_mips_emul_hypcall(struct kvm_vcpu * vcpu,union mips_instruction inst)17*4882a593Smuzhiyun enum emulation_result kvm_mips_emul_hypcall(struct kvm_vcpu *vcpu,
18*4882a593Smuzhiyun union mips_instruction inst)
19*4882a593Smuzhiyun {
20*4882a593Smuzhiyun unsigned int code = (inst.co_format.code >> 5) & 0x3ff;
21*4882a593Smuzhiyun
22*4882a593Smuzhiyun kvm_debug("[%#lx] HYPCALL %#03x\n", vcpu->arch.pc, code);
23*4882a593Smuzhiyun
24*4882a593Smuzhiyun switch (code) {
25*4882a593Smuzhiyun case 0:
26*4882a593Smuzhiyun return EMULATE_HYPERCALL;
27*4882a593Smuzhiyun default:
28*4882a593Smuzhiyun return EMULATE_FAIL;
29*4882a593Smuzhiyun };
30*4882a593Smuzhiyun }
31*4882a593Smuzhiyun
kvm_mips_hypercall(struct kvm_vcpu * vcpu,unsigned long num,const unsigned long * args,unsigned long * hret)32*4882a593Smuzhiyun static int kvm_mips_hypercall(struct kvm_vcpu *vcpu, unsigned long num,
33*4882a593Smuzhiyun const unsigned long *args, unsigned long *hret)
34*4882a593Smuzhiyun {
35*4882a593Smuzhiyun /* Report unimplemented hypercall to guest */
36*4882a593Smuzhiyun *hret = -KVM_ENOSYS;
37*4882a593Smuzhiyun return RESUME_GUEST;
38*4882a593Smuzhiyun }
39*4882a593Smuzhiyun
kvm_mips_handle_hypcall(struct kvm_vcpu * vcpu)40*4882a593Smuzhiyun int kvm_mips_handle_hypcall(struct kvm_vcpu *vcpu)
41*4882a593Smuzhiyun {
42*4882a593Smuzhiyun unsigned long num, args[MAX_HYPCALL_ARGS];
43*4882a593Smuzhiyun
44*4882a593Smuzhiyun /* read hypcall number and arguments */
45*4882a593Smuzhiyun num = vcpu->arch.gprs[2]; /* v0 */
46*4882a593Smuzhiyun args[0] = vcpu->arch.gprs[4]; /* a0 */
47*4882a593Smuzhiyun args[1] = vcpu->arch.gprs[5]; /* a1 */
48*4882a593Smuzhiyun args[2] = vcpu->arch.gprs[6]; /* a2 */
49*4882a593Smuzhiyun args[3] = vcpu->arch.gprs[7]; /* a3 */
50*4882a593Smuzhiyun
51*4882a593Smuzhiyun return kvm_mips_hypercall(vcpu, num,
52*4882a593Smuzhiyun args, &vcpu->arch.gprs[2] /* v0 */);
53*4882a593Smuzhiyun }
54