Implement LoongArch vcpu get registers and set registers operations, it
is called when user space use the ioctl interface to get or set regs.
Reviewed-by: Bibo Mao <maobibo@xxxxxxxxxxx>
Signed-off-by: Tianrui Zhao <zhaotianrui@xxxxxxxxxxx>
---
arch/loongarch/kvm/csr_ops.S | 76 +++++++++++++
arch/loongarch/kvm/vcpu.c | 206 +++++++++++++++++++++++++++++++++++
2 files changed, 282 insertions(+)
create mode 100644 arch/loongarch/kvm/csr_ops.S
diff --git a/arch/loongarch/kvm/csr_ops.S b/arch/loongarch/kvm/csr_ops.S
new file mode 100644
index 000000000000..8a149af3241b
--- /dev/null
+++ b/arch/loongarch/kvm/csr_ops.S
@@ -0,0 +1,76 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2020-2023 Loongson Technology Corporation Limited
+ */
+
+#include <asm/regdef.h>
+#include <linux/linkage.h>
+ .text
+ .section .text
+ .cfi_sections .debug_frame
+/*
+ * we have splited hw gcsr into three parts, so we can
+ * calculate the code offset by gcsrid and jump here to
+ * run the gcsrwr instruction.
+ */
+SYM_FUNC_START(set_hw_gcsr)
+ addi.d t0, a0, 0
+ addi.w t1, zero, 96
+ bltu t1, t0, 1f
+ la.pcrel t0, 10f
+ alsl.d t0, a0, t0, 3
+ jr t0
+1:
+ addi.w t1, a0, -128
+ addi.w t2, zero, 15
+ bltu t2, t1, 2f
+ la.pcrel t0, 11f
+ alsl.d t0, t1, t0, 3
+ jr t0
+2:
+ addi.w t1, a0, -384
+ addi.w t2, zero, 3
+ bltu t2, t1, 3f
+ la.pcrel t0, 12f
+ alsl.d t0, t1, t0, 3
+ jr t0
+3:
+ addi.w a0, zero, -1
+ jr ra
+/*
+ * write guest csr
+ * 0x05000000 | (LOONGARCH_CSR_XXX << 10) | 1 << 5 | a1
+ * range from 0x0(KVM_CSR_CRMD) to 0x60 (KVM_CSR_LLBCTL)
+ */
+10:
+ csrnum = 0
+ .rept 0x61
+ .word 0x05000020 | csrnum << 10 | 5
+ jr ra
+ csrnum = csrnum + 1
+ .endr
+/*
+ * write guest csr
+ * 0x05000000 | (LOONGARCH_CSR_XXX << 10) | 1<<5 | a1
+ * range from 0x80 (KVM_CSR_IMPCTL1) to 0x8f (KVM_CSR_TLBRPRMD)
+ */
+11:
+ csrnum = 0x80
+ .rept 0x10
+ .word 0x05000020 | csrnum << 10 | 5
+ jr ra
+ csrnum = csrnum + 1
+ .endr
+/*
+ * write guest csr
+ * 0x05000000 | (LOONGARCH_CSR_XXX << 10) | 1<<5 | a1
+ * range from 0x180(KVM_CSR_DMWIN0) to 0x183(KVM_CSR_DMWIN3)
+ */
+12:
+ csrnum = 0x180
+ .rept 0x4
+ .word 0x05000020 | csrnum << 10 | 5
+ jr ra
+ csrnum = csrnum + 1
+ .endr
+SYM_FUNC_END(set_hw_gcsr)
diff --git a/arch/loongarch/kvm/vcpu.c b/arch/loongarch/kvm/vcpu.c
index a45e9d9efe5b..b0cce413762d 100644
--- a/arch/loongarch/kvm/vcpu.c
+++ b/arch/loongarch/kvm/vcpu.c
@@ -12,6 +12,212 @@
#define CREATE_TRACE_POINTS
#include "trace.h"
+int _kvm_getcsr(struct kvm_vcpu *vcpu, unsigned int id, u64 *v)
+{
+ unsigned long val;
+ struct loongarch_csrs *csr = vcpu->arch.csr;
+
+ if (get_gcsr_flag(id) & INVALID_GCSR)
+ return -EINVAL;
+
+ if (id == LOONGARCH_CSR_ESTAT) {
+ /* interrupt status IP0 -- IP7 from GINTC */
+ val = kvm_read_sw_gcsr(csr, LOONGARCH_CSR_GINTC) & 0xff;
+ *v = kvm_read_sw_gcsr(csr, id) | (val << 2);
+ return 0;
+ }
+
+ /*
+ * get software csr state if csrid is valid, since software
+ * csr state is consistent with hardware
+ */
+ *v = kvm_read_sw_gcsr(csr, id);
+
+ return 0;
+}
+
+int _kvm_setcsr(struct kvm_vcpu *vcpu, unsigned int id, u64 val)
+{
+ struct loongarch_csrs *csr = vcpu->arch.csr;
+ int ret = 0, gintc;
+
+ if (get_gcsr_flag(id) & INVALID_GCSR)
+ return -EINVAL;
+
+ if (id == LOONGARCH_CSR_ESTAT) {
+ /* estat IP0~IP7 inject through guestexcept */
+ gintc = (val >> 2) & 0xff;
+ write_csr_gintc(gintc);
+ kvm_set_sw_gcsr(csr, LOONGARCH_CSR_GINTC, gintc);
+
+ gintc = val & ~(0xffUL << 2);
+ write_gcsr_estat(gintc);
+ kvm_set_sw_gcsr(csr, LOONGARCH_CSR_ESTAT, gintc);
+
+ return ret;
+ }
+
+ if (get_gcsr_flag(id) & HW_GCSR) {
+ set_hw_gcsr(id, val);
+ /* write sw gcsr to keep consistent with hardware */
+ kvm_write_sw_gcsr(csr, id, val);
+ } else
+ kvm_write_sw_gcsr(csr, id, val);
+
+ return ret;
+}
+
+static int _kvm_get_one_reg(struct kvm_vcpu *vcpu,
+ const struct kvm_one_reg *reg, s64 *v)
+{
+ int reg_idx, ret = 0;
+
+ if ((reg->id & KVM_REG_LOONGARCH_MASK) == KVM_REG_LOONGARCH_CSR) {
+ reg_idx = KVM_GET_IOC_CSRIDX(reg->id);
+ ret = _kvm_getcsr(vcpu, reg_idx, v);
+ } else if (reg->id == KVM_REG_LOONGARCH_COUNTER)
+ *v = drdtime() + vcpu->kvm->arch.time_offset;
+ else
+ ret = -EINVAL;
+
+ return ret;
+}
+
+static int _kvm_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
+{
+ int ret = -EINVAL;
+ s64 v;
+
+ if ((reg->id & KVM_REG_SIZE_MASK) != KVM_REG_SIZE_U64)
+ return ret;
+
+ if (_kvm_get_one_reg(vcpu, reg, &v))
+ return ret;
+
+ return put_user(v, (u64 __user *)(long)reg->addr);
+}
+
+static int _kvm_set_one_reg(struct kvm_vcpu *vcpu,
+ const struct kvm_one_reg *reg,
+ s64 v)
+{
+ int ret = 0;
+ unsigned long flags;
+ u64 val;
+ int reg_idx;
+
+ val = v;
+ if ((reg->id & KVM_REG_LOONGARCH_MASK) == KVM_REG_LOONGARCH_CSR) {
+ reg_idx = KVM_GET_IOC_CSRIDX(reg->id);
+ ret = _kvm_setcsr(vcpu, reg_idx, val);
+ } else if (reg->id == KVM_REG_LOONGARCH_COUNTER) {
+ local_irq_save(flags);
+ /*
+ * gftoffset is relative with board, not vcpu
+ * only set for the first time for smp system
+ */
+ if (vcpu->vcpu_id == 0)
+ vcpu->kvm->arch.time_offset = (signed long)(v - drdtime());
+ write_csr_gcntc((ulong)vcpu->kvm->arch.time_offset);
+ local_irq_restore(flags);
+ } else if (reg->id == KVM_REG_LOONGARCH_VCPU_RESET) {
+ kvm_reset_timer(vcpu);
+ memset(&vcpu->arch.irq_pending, 0, sizeof(vcpu->arch.irq_pending));
+ memset(&vcpu->arch.irq_clear, 0, sizeof(vcpu->arch.irq_clear));
+ } else
+ ret = -EINVAL;
+
+ return ret;
+}
+
+static int _kvm_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
+{
+ s64 v;
+ int ret = -EINVAL;
+
+ if ((reg->id & KVM_REG_SIZE_MASK) != KVM_REG_SIZE_U64)
+ return ret;
+
+ if (get_user(v, (u64 __user *)(long)reg->addr))
+ return ret;
+
+ return _kvm_set_one_reg(vcpu, reg, v);
+}
+
+int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
+ struct kvm_sregs *sregs)
+{
+ return -ENOIOCTLCMD;
+}
+
+int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
+ struct kvm_sregs *sregs)
+{
+ return -ENOIOCTLCMD;
+}
+
+int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
+{
+ int i;
+
+ vcpu_load(vcpu);
+
+ for (i = 0; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
+ regs->gpr[i] = vcpu->arch.gprs[i];
+
+ regs->pc = vcpu->arch.pc;
+
+ vcpu_put(vcpu);
+ return 0;
+}
+
+int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
+{
+ int i;
+
+ vcpu_load(vcpu);
+
+ for (i = 1; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
+ vcpu->arch.gprs[i] = regs->gpr[i];
+ vcpu->arch.gprs[0] = 0; /* zero is special, and cannot be set. */
+ vcpu->arch.pc = regs->pc;
+
+ vcpu_put(vcpu);
+ return 0;
+}
+
+long kvm_arch_vcpu_ioctl(struct file *filp,
+ unsigned int ioctl, unsigned long arg)
+{
+ struct kvm_vcpu *vcpu = filp->private_data;
+ void __user *argp = (void __user *)arg;
+ long r;
+
+ vcpu_load(vcpu);
+
+ switch (ioctl) {
+ case KVM_SET_ONE_REG:
+ case KVM_GET_ONE_REG: {
+ struct kvm_one_reg reg;
+
+ r = -EFAULT;
+ if (copy_from_user(®, argp, sizeof(reg)))
+ break;
+ if (ioctl == KVM_SET_ONE_REG)
+ r = _kvm_set_reg(vcpu, ®);
+ else
+ r = _kvm_get_reg(vcpu, ®);
+ break;
+ }
+ default:
+ r = -ENOIOCTLCMD;
+ break;
+ }
+
+ vcpu_put(vcpu);
+ return r;
+}
+
int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
{
return 0;
--
2.39.1
