Add support for saving and restoring VFP register state from the
kernel. This includes a check that the KVM-created CPU has full
VFP support (as the TCG Cortex-A15 model always does), since for
the moment ARM QEMU doesn't have any way to tweak optional features
on created CPUs.
Signed-off-by: Peter Maydell <peter.maydell@xxxxxxxxxx>
---
target-arm/kvm.c | 78 +++++++++++++++++++++++++++++++++++++++++++++++++++---
1 file changed, 75 insertions(+), 3 deletions(-)
diff --git a/target-arm/kvm.c b/target-arm/kvm.c
index db13568..13f7b0d 100644
--- a/target-arm/kvm.c
+++ b/target-arm/kvm.c
@@ -38,10 +38,28 @@ int kvm_arch_init(KVMState *s)
int kvm_arch_init_vcpu(CPUState *cs)
{
struct kvm_vcpu_init init;
+ int ret;
+ uint64_t v;
+ struct kvm_one_reg r;
init.target = KVM_ARM_TARGET_CORTEX_A15;
memset(init.features, 0, sizeof(init.features));
- return kvm_vcpu_ioctl(cs, KVM_ARM_VCPU_INIT, &init);
+ ret = kvm_vcpu_ioctl(cs, KVM_ARM_VCPU_INIT, &init);
+ if (ret) {
+ return ret;
+ }
+ /* Query the kernel to make sure it supports 32 VFP
+ * registers: QEMU's "cortex-a15" CPU is always a
+ * VFP-D32 core. The simplest way to do this is just
+ * to attempt to read register d31.
+ */
+ r.id = KVM_REG_ARM | KVM_REG_SIZE_U64 | KVM_REG_ARM_VFP | 31;
+ r.addr = (uintptr_t)(&v);
+ ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &r);
+ if (ret == ENOENT) {
+ return EINVAL;
+ }
+ return ret;
}
typedef struct Reg {
@@ -67,6 +85,13 @@ typedef struct Reg {
offsetof(CPUARMState, QEMUFIELD) \
}
+#define VFPSYSREG(R) \
+ { \
+ KVM_REG_ARM | KVM_REG_SIZE_U32 | KVM_REG_ARM_VFP | \
+ KVM_REG_ARM_VFP_##R, \
+ offsetof(CPUARMState, vfp.xregs[ARM_VFP_##R]) \
+ }
+
static const Reg regs[] = {
/* R0_usr .. R14_usr */
COREREG(usr_regs.uregs[0], regs[0]),
@@ -114,6 +139,13 @@ static const Reg regs[] = {
CP15REG(1, 0, 0, 0, cp15.c1_sys), /* SCTLR */
CP15REG(2, 0, 0, 2, cp15.c2_control), /* TTBCR */
CP15REG(3, 0, 0, 0, cp15.c3), /* DACR */
+ /* VFP system registers */
+ VFPSYSREG(FPSID),
+ VFPSYSREG(MVFR1),
+ VFPSYSREG(MVFR0),
+ VFPSYSREG(FPEXC),
+ VFPSYSREG(FPINST),
+ VFPSYSREG(FPINST2),
};
int kvm_arch_put_registers(CPUState *cs, int level)
@@ -123,7 +155,7 @@ int kvm_arch_put_registers(CPUState *cs, int level)
struct kvm_one_reg r;
int mode, bn;
int ret, i;
- uint32_t cpsr;
+ uint32_t cpsr, fpscr;
uint64_t ttbr;
/* Make sure the banked regs are properly set */
@@ -174,6 +206,26 @@ int kvm_arch_put_registers(CPUState *cs, int level)
(2 << KVM_REG_ARM_CRM_SHIFT) | (1 << KVM_REG_ARM_OPC1_SHIFT);
r.addr = (uintptr_t)(&ttbr);
ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, &r);
+ if (ret) {
+ return ret;
+ }
+
+ /* VFP registers */
+ r.id = KVM_REG_ARM | KVM_REG_SIZE_U64 | KVM_REG_ARM_VFP;
+ for (i = 0; i < 32; i++) {
+ r.addr = (uintptr_t)(&env->vfp.regs[i]);
+ ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, &r);
+ if (ret) {
+ return ret;
+ }
+ r.id++;
+ }
+
+ r.id = KVM_REG_ARM | KVM_REG_SIZE_U32 | KVM_REG_ARM_VFP |
+ KVM_REG_ARM_VFP_FPSCR;
+ fpscr = vfp_get_fpscr(env);
+ r.addr = (uintptr_t)&fpscr;
+ ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, &r);
return ret;
}
@@ -185,7 +237,7 @@ int kvm_arch_get_registers(CPUState *cs)
struct kvm_one_reg r;
int mode, bn;
int ret, i;
- uint32_t cpsr;
+ uint32_t cpsr, fpscr;
uint64_t ttbr;
for (i = 0; i < ARRAY_SIZE(regs); i++) {
@@ -250,6 +302,26 @@ int kvm_arch_get_registers(CPUState *cs)
env->cp15.c2_mask = ~(0xffffffffu >> env->cp15.c2_control);
env->cp15.c2_base_mask = ~(0x3fffu >> env->cp15.c2_control);
+ /* VFP registers */
+ r.id = KVM_REG_ARM | KVM_REG_SIZE_U64 | KVM_REG_ARM_VFP;
+ for (i = 0; i < 32; i++) {
+ r.addr = (uintptr_t)(&env->vfp.regs[i]);
+ ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &r);
+ if (ret) {
+ return ret;
+ }
+ r.id++;
+ }
+
+ r.id = KVM_REG_ARM | KVM_REG_SIZE_U32 | KVM_REG_ARM_VFP |
+ KVM_REG_ARM_VFP_FPSCR;
+ r.addr = (uintptr_t)&fpscr;
+ ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &r);
+ if (ret) {
+ return ret;
+ }
+ vfp_set_fpscr(env, fpscr);
+
return 0;
}
--
1.7.9.5
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