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-rw-r--r--target-arm/kvm32.c515
1 files changed, 515 insertions, 0 deletions
diff --git a/target-arm/kvm32.c b/target-arm/kvm32.c
new file mode 100644
index 0000000000..a4fde07969
--- /dev/null
+++ b/target-arm/kvm32.c
@@ -0,0 +1,515 @@
+/*
+ * ARM implementation of KVM hooks, 32 bit specific code.
+ *
+ * Copyright Christoffer Dall 2009-2010
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ */
+
+#include <stdio.h>
+#include <sys/types.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+
+#include <linux/kvm.h>
+
+#include "qemu-common.h"
+#include "qemu/timer.h"
+#include "sysemu/sysemu.h"
+#include "sysemu/kvm.h"
+#include "kvm_arm.h"
+#include "cpu.h"
+#include "hw/arm/arm.h"
+
+static inline void set_feature(uint64_t *features, int feature)
+{
+ *features |= 1ULL << feature;
+}
+
+bool kvm_arm_get_host_cpu_features(ARMHostCPUClass *ahcc)
+{
+ /* Identify the feature bits corresponding to the host CPU, and
+ * fill out the ARMHostCPUClass fields accordingly. To do this
+ * we have to create a scratch VM, create a single CPU inside it,
+ * and then query that CPU for the relevant ID registers.
+ */
+ int i, ret, fdarray[3];
+ uint32_t midr, id_pfr0, id_isar0, mvfr1;
+ uint64_t features = 0;
+ /* Old kernels may not know about the PREFERRED_TARGET ioctl: however
+ * we know these will only support creating one kind of guest CPU,
+ * which is its preferred CPU type.
+ */
+ static const uint32_t cpus_to_try[] = {
+ QEMU_KVM_ARM_TARGET_CORTEX_A15,
+ QEMU_KVM_ARM_TARGET_NONE
+ };
+ struct kvm_vcpu_init init;
+ struct kvm_one_reg idregs[] = {
+ {
+ .id = KVM_REG_ARM | KVM_REG_SIZE_U32
+ | ENCODE_CP_REG(15, 0, 0, 0, 0, 0),
+ .addr = (uintptr_t)&midr,
+ },
+ {
+ .id = KVM_REG_ARM | KVM_REG_SIZE_U32
+ | ENCODE_CP_REG(15, 0, 0, 1, 0, 0),
+ .addr = (uintptr_t)&id_pfr0,
+ },
+ {
+ .id = KVM_REG_ARM | KVM_REG_SIZE_U32
+ | ENCODE_CP_REG(15, 0, 0, 2, 0, 0),
+ .addr = (uintptr_t)&id_isar0,
+ },
+ {
+ .id = KVM_REG_ARM | KVM_REG_SIZE_U32
+ | KVM_REG_ARM_VFP | KVM_REG_ARM_VFP_MVFR1,
+ .addr = (uintptr_t)&mvfr1,
+ },
+ };
+
+ if (!kvm_arm_create_scratch_host_vcpu(cpus_to_try, fdarray, &init)) {
+ return false;
+ }
+
+ ahcc->target = init.target;
+
+ /* This is not strictly blessed by the device tree binding docs yet,
+ * but in practice the kernel does not care about this string so
+ * there is no point maintaining an KVM_ARM_TARGET_* -> string table.
+ */
+ ahcc->dtb_compatible = "arm,arm-v7";
+
+ for (i = 0; i < ARRAY_SIZE(idregs); i++) {
+ ret = ioctl(fdarray[2], KVM_GET_ONE_REG, &idregs[i]);
+ if (ret) {
+ break;
+ }
+ }
+
+ kvm_arm_destroy_scratch_host_vcpu(fdarray);
+
+ if (ret) {
+ return false;
+ }
+
+ /* Now we've retrieved all the register information we can
+ * set the feature bits based on the ID register fields.
+ * We can assume any KVM supporting CPU is at least a v7
+ * with VFPv3, LPAE and the generic timers; this in turn implies
+ * most of the other feature bits, but a few must be tested.
+ */
+ set_feature(&features, ARM_FEATURE_V7);
+ set_feature(&features, ARM_FEATURE_VFP3);
+ set_feature(&features, ARM_FEATURE_LPAE);
+ set_feature(&features, ARM_FEATURE_GENERIC_TIMER);
+
+ switch (extract32(id_isar0, 24, 4)) {
+ case 1:
+ set_feature(&features, ARM_FEATURE_THUMB_DIV);
+ break;
+ case 2:
+ set_feature(&features, ARM_FEATURE_ARM_DIV);
+ set_feature(&features, ARM_FEATURE_THUMB_DIV);
+ break;
+ default:
+ break;
+ }
+
+ if (extract32(id_pfr0, 12, 4) == 1) {
+ set_feature(&features, ARM_FEATURE_THUMB2EE);
+ }
+ if (extract32(mvfr1, 20, 4) == 1) {
+ set_feature(&features, ARM_FEATURE_VFP_FP16);
+ }
+ if (extract32(mvfr1, 12, 4) == 1) {
+ set_feature(&features, ARM_FEATURE_NEON);
+ }
+ if (extract32(mvfr1, 28, 4) == 1) {
+ /* FMAC support implies VFPv4 */
+ set_feature(&features, ARM_FEATURE_VFP4);
+ }
+
+ ahcc->features = features;
+
+ return true;
+}
+
+static bool reg_syncs_via_tuple_list(uint64_t regidx)
+{
+ /* Return true if the regidx is a register we should synchronize
+ * via the cpreg_tuples array (ie is not a core reg we sync by
+ * hand in kvm_arch_get/put_registers())
+ */
+ switch (regidx & KVM_REG_ARM_COPROC_MASK) {
+ case KVM_REG_ARM_CORE:
+ case KVM_REG_ARM_VFP:
+ return false;
+ default:
+ return true;
+ }
+}
+
+static int compare_u64(const void *a, const void *b)
+{
+ if (*(uint64_t *)a > *(uint64_t *)b) {
+ return 1;
+ }
+ if (*(uint64_t *)a < *(uint64_t *)b) {
+ return -1;
+ }
+ return 0;
+}
+
+int kvm_arch_init_vcpu(CPUState *cs)
+{
+ struct kvm_vcpu_init init;
+ int i, ret, arraylen;
+ uint64_t v;
+ struct kvm_one_reg r;
+ struct kvm_reg_list rl;
+ struct kvm_reg_list *rlp;
+ ARMCPU *cpu = ARM_CPU(cs);
+
+ if (cpu->kvm_target == QEMU_KVM_ARM_TARGET_NONE) {
+ fprintf(stderr, "KVM is not supported for this guest CPU type\n");
+ return -EINVAL;
+ }
+
+ init.target = cpu->kvm_target;
+ memset(init.features, 0, sizeof(init.features));
+ if (cpu->start_powered_off) {
+ init.features[0] = 1 << KVM_ARM_VCPU_POWER_OFF;
+ }
+ 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;
+ }
+
+ /* Populate the cpreg list based on the kernel's idea
+ * of what registers exist (and throw away the TCG-created list).
+ */
+ rl.n = 0;
+ ret = kvm_vcpu_ioctl(cs, KVM_GET_REG_LIST, &rl);
+ if (ret != -E2BIG) {
+ return ret;
+ }
+ rlp = g_malloc(sizeof(struct kvm_reg_list) + rl.n * sizeof(uint64_t));
+ rlp->n = rl.n;
+ ret = kvm_vcpu_ioctl(cs, KVM_GET_REG_LIST, rlp);
+ if (ret) {
+ goto out;
+ }
+ /* Sort the list we get back from the kernel, since cpreg_tuples
+ * must be in strictly ascending order.
+ */
+ qsort(&rlp->reg, rlp->n, sizeof(rlp->reg[0]), compare_u64);
+
+ for (i = 0, arraylen = 0; i < rlp->n; i++) {
+ if (!reg_syncs_via_tuple_list(rlp->reg[i])) {
+ continue;
+ }
+ switch (rlp->reg[i] & KVM_REG_SIZE_MASK) {
+ case KVM_REG_SIZE_U32:
+ case KVM_REG_SIZE_U64:
+ break;
+ default:
+ fprintf(stderr, "Can't handle size of register in kernel list\n");
+ ret = -EINVAL;
+ goto out;
+ }
+
+ arraylen++;
+ }
+
+ cpu->cpreg_indexes = g_renew(uint64_t, cpu->cpreg_indexes, arraylen);
+ cpu->cpreg_values = g_renew(uint64_t, cpu->cpreg_values, arraylen);
+ cpu->cpreg_vmstate_indexes = g_renew(uint64_t, cpu->cpreg_vmstate_indexes,
+ arraylen);
+ cpu->cpreg_vmstate_values = g_renew(uint64_t, cpu->cpreg_vmstate_values,
+ arraylen);
+ cpu->cpreg_array_len = arraylen;
+ cpu->cpreg_vmstate_array_len = arraylen;
+
+ for (i = 0, arraylen = 0; i < rlp->n; i++) {
+ uint64_t regidx = rlp->reg[i];
+ if (!reg_syncs_via_tuple_list(regidx)) {
+ continue;
+ }
+ cpu->cpreg_indexes[arraylen] = regidx;
+ arraylen++;
+ }
+ assert(cpu->cpreg_array_len == arraylen);
+
+ if (!write_kvmstate_to_list(cpu)) {
+ /* Shouldn't happen unless kernel is inconsistent about
+ * what registers exist.
+ */
+ fprintf(stderr, "Initial read of kernel register state failed\n");
+ ret = -EINVAL;
+ goto out;
+ }
+
+ /* Save a copy of the initial register values so that we can
+ * feed it back to the kernel on VCPU reset.
+ */
+ cpu->cpreg_reset_values = g_memdup(cpu->cpreg_values,
+ cpu->cpreg_array_len *
+ sizeof(cpu->cpreg_values[0]));
+
+out:
+ g_free(rlp);
+ return ret;
+}
+
+typedef struct Reg {
+ uint64_t id;
+ int offset;
+} Reg;
+
+#define COREREG(KERNELNAME, QEMUFIELD) \
+ { \
+ KVM_REG_ARM | KVM_REG_SIZE_U32 | \
+ KVM_REG_ARM_CORE | KVM_REG_ARM_CORE_REG(KERNELNAME), \
+ 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]),
+ COREREG(usr_regs.uregs[1], regs[1]),
+ COREREG(usr_regs.uregs[2], regs[2]),
+ COREREG(usr_regs.uregs[3], regs[3]),
+ COREREG(usr_regs.uregs[4], regs[4]),
+ COREREG(usr_regs.uregs[5], regs[5]),
+ COREREG(usr_regs.uregs[6], regs[6]),
+ COREREG(usr_regs.uregs[7], regs[7]),
+ COREREG(usr_regs.uregs[8], usr_regs[0]),
+ COREREG(usr_regs.uregs[9], usr_regs[1]),
+ COREREG(usr_regs.uregs[10], usr_regs[2]),
+ COREREG(usr_regs.uregs[11], usr_regs[3]),
+ COREREG(usr_regs.uregs[12], usr_regs[4]),
+ COREREG(usr_regs.uregs[13], banked_r13[0]),
+ COREREG(usr_regs.uregs[14], banked_r14[0]),
+ /* R13, R14, SPSR for SVC, ABT, UND, IRQ banks */
+ COREREG(svc_regs[0], banked_r13[1]),
+ COREREG(svc_regs[1], banked_r14[1]),
+ COREREG(svc_regs[2], banked_spsr[1]),
+ COREREG(abt_regs[0], banked_r13[2]),
+ COREREG(abt_regs[1], banked_r14[2]),
+ COREREG(abt_regs[2], banked_spsr[2]),
+ COREREG(und_regs[0], banked_r13[3]),
+ COREREG(und_regs[1], banked_r14[3]),
+ COREREG(und_regs[2], banked_spsr[3]),
+ COREREG(irq_regs[0], banked_r13[4]),
+ COREREG(irq_regs[1], banked_r14[4]),
+ COREREG(irq_regs[2], banked_spsr[4]),
+ /* R8_fiq .. R14_fiq and SPSR_fiq */
+ COREREG(fiq_regs[0], fiq_regs[0]),
+ COREREG(fiq_regs[1], fiq_regs[1]),
+ COREREG(fiq_regs[2], fiq_regs[2]),
+ COREREG(fiq_regs[3], fiq_regs[3]),
+ COREREG(fiq_regs[4], fiq_regs[4]),
+ COREREG(fiq_regs[5], banked_r13[5]),
+ COREREG(fiq_regs[6], banked_r14[5]),
+ COREREG(fiq_regs[7], banked_spsr[5]),
+ /* R15 */
+ COREREG(usr_regs.uregs[15], regs[15]),
+ /* VFP system registers */
+ VFPSYSREG(FPSID),
+ VFPSYSREG(MVFR1),
+ VFPSYSREG(MVFR0),
+ VFPSYSREG(FPEXC),
+ VFPSYSREG(FPINST),
+ VFPSYSREG(FPINST2),
+};
+
+int kvm_arch_put_registers(CPUState *cs, int level)
+{
+ ARMCPU *cpu = ARM_CPU(cs);
+ CPUARMState *env = &cpu->env;
+ struct kvm_one_reg r;
+ int mode, bn;
+ int ret, i;
+ uint32_t cpsr, fpscr;
+
+ /* Make sure the banked regs are properly set */
+ mode = env->uncached_cpsr & CPSR_M;
+ bn = bank_number(mode);
+ if (mode == ARM_CPU_MODE_FIQ) {
+ memcpy(env->fiq_regs, env->regs + 8, 5 * sizeof(uint32_t));
+ } else {
+ memcpy(env->usr_regs, env->regs + 8, 5 * sizeof(uint32_t));
+ }
+ env->banked_r13[bn] = env->regs[13];
+ env->banked_r14[bn] = env->regs[14];
+ env->banked_spsr[bn] = env->spsr;
+
+ /* Now we can safely copy stuff down to the kernel */
+ for (i = 0; i < ARRAY_SIZE(regs); i++) {
+ r.id = regs[i].id;
+ r.addr = (uintptr_t)(env) + regs[i].offset;
+ ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, &r);
+ if (ret) {
+ return ret;
+ }
+ }
+
+ /* Special cases which aren't a single CPUARMState field */
+ cpsr = cpsr_read(env);
+ r.id = KVM_REG_ARM | KVM_REG_SIZE_U32 |
+ KVM_REG_ARM_CORE | KVM_REG_ARM_CORE_REG(usr_regs.ARM_cpsr);
+ r.addr = (uintptr_t)(&cpsr);
+ 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);
+ if (ret) {
+ return ret;
+ }
+
+ /* Note that we do not call write_cpustate_to_list()
+ * here, so we are only writing the tuple list back to
+ * KVM. This is safe because nothing can change the
+ * CPUARMState cp15 fields (in particular gdb accesses cannot)
+ * and so there are no changes to sync. In fact syncing would
+ * be wrong at this point: for a constant register where TCG and
+ * KVM disagree about its value, the preceding write_list_to_cpustate()
+ * would not have had any effect on the CPUARMState value (since the
+ * register is read-only), and a write_cpustate_to_list() here would
+ * then try to write the TCG value back into KVM -- this would either
+ * fail or incorrectly change the value the guest sees.
+ *
+ * If we ever want to allow the user to modify cp15 registers via
+ * the gdb stub, we would need to be more clever here (for instance
+ * tracking the set of registers kvm_arch_get_registers() successfully
+ * managed to update the CPUARMState with, and only allowing those
+ * to be written back up into the kernel).
+ */
+ if (!write_list_to_kvmstate(cpu)) {
+ return EINVAL;
+ }
+
+ return ret;
+}
+
+int kvm_arch_get_registers(CPUState *cs)
+{
+ ARMCPU *cpu = ARM_CPU(cs);
+ CPUARMState *env = &cpu->env;
+ struct kvm_one_reg r;
+ int mode, bn;
+ int ret, i;
+ uint32_t cpsr, fpscr;
+
+ for (i = 0; i < ARRAY_SIZE(regs); i++) {
+ r.id = regs[i].id;
+ r.addr = (uintptr_t)(env) + regs[i].offset;
+ ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &r);
+ if (ret) {
+ return ret;
+ }
+ }
+
+ /* Special cases which aren't a single CPUARMState field */
+ r.id = KVM_REG_ARM | KVM_REG_SIZE_U32 |
+ KVM_REG_ARM_CORE | KVM_REG_ARM_CORE_REG(usr_regs.ARM_cpsr);
+ r.addr = (uintptr_t)(&cpsr);
+ ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &r);
+ if (ret) {
+ return ret;
+ }
+ cpsr_write(env, cpsr, 0xffffffff);
+
+ /* Make sure the current mode regs are properly set */
+ mode = env->uncached_cpsr & CPSR_M;
+ bn = bank_number(mode);
+ if (mode == ARM_CPU_MODE_FIQ) {
+ memcpy(env->regs + 8, env->fiq_regs, 5 * sizeof(uint32_t));
+ } else {
+ memcpy(env->regs + 8, env->usr_regs, 5 * sizeof(uint32_t));
+ }
+ env->regs[13] = env->banked_r13[bn];
+ env->regs[14] = env->banked_r14[bn];
+ env->spsr = env->banked_spsr[bn];
+
+ /* 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);
+
+ if (!write_kvmstate_to_list(cpu)) {
+ return EINVAL;
+ }
+ /* Note that it's OK to have registers which aren't in CPUState,
+ * so we can ignore a failure return here.
+ */
+ write_list_to_cpustate(cpu);
+
+ return 0;
+}
+
+void kvm_arch_reset_vcpu(CPUState *cs)
+{
+ /* Feed the kernel back its initial register state */
+ ARMCPU *cpu = ARM_CPU(cs);
+
+ memmove(cpu->cpreg_values, cpu->cpreg_reset_values,
+ cpu->cpreg_array_len * sizeof(cpu->cpreg_values[0]));
+
+ if (!write_list_to_kvmstate(cpu)) {
+ abort();
+ }
+}
generated by cgit v1.2.3 (git 2.26.2) at 2024-12-30 18:40:30 +0000