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-rw-r--r--arch/mips/kvm/emulate.c1650
1 files changed, 1650 insertions, 0 deletions
diff --git a/arch/mips/kvm/emulate.c b/arch/mips/kvm/emulate.c
new file mode 100644
index 000000000..e64372b8f
--- /dev/null
+++ b/arch/mips/kvm/emulate.c
@@ -0,0 +1,1650 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * KVM/MIPS: Instruction/Exception emulation
+ *
+ * Copyright (C) 2012 MIPS Technologies, Inc. All rights reserved.
+ * Authors: Sanjay Lal <sanjayl@kymasys.com>
+ */
+
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/ktime.h>
+#include <linux/kvm_host.h>
+#include <linux/vmalloc.h>
+#include <linux/fs.h>
+#include <linux/memblock.h>
+#include <linux/random.h>
+#include <asm/page.h>
+#include <asm/cacheflush.h>
+#include <asm/cacheops.h>
+#include <asm/cpu-info.h>
+#include <asm/mmu_context.h>
+#include <asm/tlbflush.h>
+#include <asm/inst.h>
+
+#undef CONFIG_MIPS_MT
+#include <asm/r4kcache.h>
+#define CONFIG_MIPS_MT
+
+#include "interrupt.h"
+
+#include "trace.h"
+
+/*
+ * Compute the return address and do emulate branch simulation, if required.
+ * This function should be called only in branch delay slot active.
+ */
+static int kvm_compute_return_epc(struct kvm_vcpu *vcpu, unsigned long instpc,
+ unsigned long *out)
+{
+ unsigned int dspcontrol;
+ union mips_instruction insn;
+ struct kvm_vcpu_arch *arch = &vcpu->arch;
+ long epc = instpc;
+ long nextpc;
+ int err;
+
+ if (epc & 3) {
+ kvm_err("%s: unaligned epc\n", __func__);
+ return -EINVAL;
+ }
+
+ /* Read the instruction */
+ err = kvm_get_badinstrp((u32 *)epc, vcpu, &insn.word);
+ if (err)
+ return err;
+
+ switch (insn.i_format.opcode) {
+ /* jr and jalr are in r_format format. */
+ case spec_op:
+ switch (insn.r_format.func) {
+ case jalr_op:
+ arch->gprs[insn.r_format.rd] = epc + 8;
+ fallthrough;
+ case jr_op:
+ nextpc = arch->gprs[insn.r_format.rs];
+ break;
+ default:
+ return -EINVAL;
+ }
+ break;
+
+ /*
+ * This group contains:
+ * bltz_op, bgez_op, bltzl_op, bgezl_op,
+ * bltzal_op, bgezal_op, bltzall_op, bgezall_op.
+ */
+ case bcond_op:
+ switch (insn.i_format.rt) {
+ case bltz_op:
+ case bltzl_op:
+ if ((long)arch->gprs[insn.i_format.rs] < 0)
+ epc = epc + 4 + (insn.i_format.simmediate << 2);
+ else
+ epc += 8;
+ nextpc = epc;
+ break;
+
+ case bgez_op:
+ case bgezl_op:
+ if ((long)arch->gprs[insn.i_format.rs] >= 0)
+ epc = epc + 4 + (insn.i_format.simmediate << 2);
+ else
+ epc += 8;
+ nextpc = epc;
+ break;
+
+ case bltzal_op:
+ case bltzall_op:
+ arch->gprs[31] = epc + 8;
+ if ((long)arch->gprs[insn.i_format.rs] < 0)
+ epc = epc + 4 + (insn.i_format.simmediate << 2);
+ else
+ epc += 8;
+ nextpc = epc;
+ break;
+
+ case bgezal_op:
+ case bgezall_op:
+ arch->gprs[31] = epc + 8;
+ if ((long)arch->gprs[insn.i_format.rs] >= 0)
+ epc = epc + 4 + (insn.i_format.simmediate << 2);
+ else
+ epc += 8;
+ nextpc = epc;
+ break;
+ case bposge32_op:
+ if (!cpu_has_dsp) {
+ kvm_err("%s: DSP branch but not DSP ASE\n",
+ __func__);
+ return -EINVAL;
+ }
+
+ dspcontrol = rddsp(0x01);
+
+ if (dspcontrol >= 32)
+ epc = epc + 4 + (insn.i_format.simmediate << 2);
+ else
+ epc += 8;
+ nextpc = epc;
+ break;
+ default:
+ return -EINVAL;
+ }
+ break;
+
+ /* These are unconditional and in j_format. */
+ case jal_op:
+ arch->gprs[31] = instpc + 8;
+ fallthrough;
+ case j_op:
+ epc += 4;
+ epc >>= 28;
+ epc <<= 28;
+ epc |= (insn.j_format.target << 2);
+ nextpc = epc;
+ break;
+
+ /* These are conditional and in i_format. */
+ case beq_op:
+ case beql_op:
+ if (arch->gprs[insn.i_format.rs] ==
+ arch->gprs[insn.i_format.rt])
+ epc = epc + 4 + (insn.i_format.simmediate << 2);
+ else
+ epc += 8;
+ nextpc = epc;
+ break;
+
+ case bne_op:
+ case bnel_op:
+ if (arch->gprs[insn.i_format.rs] !=
+ arch->gprs[insn.i_format.rt])
+ epc = epc + 4 + (insn.i_format.simmediate << 2);
+ else
+ epc += 8;
+ nextpc = epc;
+ break;
+
+ case blez_op: /* POP06 */
+#ifndef CONFIG_CPU_MIPSR6
+ case blezl_op: /* removed in R6 */
+#endif
+ if (insn.i_format.rt != 0)
+ goto compact_branch;
+ if ((long)arch->gprs[insn.i_format.rs] <= 0)
+ epc = epc + 4 + (insn.i_format.simmediate << 2);
+ else
+ epc += 8;
+ nextpc = epc;
+ break;
+
+ case bgtz_op: /* POP07 */
+#ifndef CONFIG_CPU_MIPSR6
+ case bgtzl_op: /* removed in R6 */
+#endif
+ if (insn.i_format.rt != 0)
+ goto compact_branch;
+ if ((long)arch->gprs[insn.i_format.rs] > 0)
+ epc = epc + 4 + (insn.i_format.simmediate << 2);
+ else
+ epc += 8;
+ nextpc = epc;
+ break;
+
+ /* And now the FPA/cp1 branch instructions. */
+ case cop1_op:
+ kvm_err("%s: unsupported cop1_op\n", __func__);
+ return -EINVAL;
+
+#ifdef CONFIG_CPU_MIPSR6
+ /* R6 added the following compact branches with forbidden slots */
+ case blezl_op: /* POP26 */
+ case bgtzl_op: /* POP27 */
+ /* only rt == 0 isn't compact branch */
+ if (insn.i_format.rt != 0)
+ goto compact_branch;
+ return -EINVAL;
+ case pop10_op:
+ case pop30_op:
+ /* only rs == rt == 0 is reserved, rest are compact branches */
+ if (insn.i_format.rs != 0 || insn.i_format.rt != 0)
+ goto compact_branch;
+ return -EINVAL;
+ case pop66_op:
+ case pop76_op:
+ /* only rs == 0 isn't compact branch */
+ if (insn.i_format.rs != 0)
+ goto compact_branch;
+ return -EINVAL;
+compact_branch:
+ /*
+ * If we've hit an exception on the forbidden slot, then
+ * the branch must not have been taken.
+ */
+ epc += 8;
+ nextpc = epc;
+ break;
+#else
+compact_branch:
+ /* Fall through - Compact branches not supported before R6 */
+#endif
+ default:
+ return -EINVAL;
+ }
+
+ *out = nextpc;
+ return 0;
+}
+
+enum emulation_result update_pc(struct kvm_vcpu *vcpu, u32 cause)
+{
+ int err;
+
+ if (cause & CAUSEF_BD) {
+ err = kvm_compute_return_epc(vcpu, vcpu->arch.pc,
+ &vcpu->arch.pc);
+ if (err)
+ return EMULATE_FAIL;
+ } else {
+ vcpu->arch.pc += 4;
+ }
+
+ kvm_debug("update_pc(): New PC: %#lx\n", vcpu->arch.pc);
+
+ return EMULATE_DONE;
+}
+
+/**
+ * kvm_get_badinstr() - Get bad instruction encoding.
+ * @opc: Guest pointer to faulting instruction.
+ * @vcpu: KVM VCPU information.
+ *
+ * Gets the instruction encoding of the faulting instruction, using the saved
+ * BadInstr register value if it exists, otherwise falling back to reading guest
+ * memory at @opc.
+ *
+ * Returns: The instruction encoding of the faulting instruction.
+ */
+int kvm_get_badinstr(u32 *opc, struct kvm_vcpu *vcpu, u32 *out)
+{
+ if (cpu_has_badinstr) {
+ *out = vcpu->arch.host_cp0_badinstr;
+ return 0;
+ } else {
+ WARN_ONCE(1, "CPU doesn't have BadInstr register\n");
+ return -EINVAL;
+ }
+}
+
+/**
+ * kvm_get_badinstrp() - Get bad prior instruction encoding.
+ * @opc: Guest pointer to prior faulting instruction.
+ * @vcpu: KVM VCPU information.
+ *
+ * Gets the instruction encoding of the prior faulting instruction (the branch
+ * containing the delay slot which faulted), using the saved BadInstrP register
+ * value if it exists, otherwise falling back to reading guest memory at @opc.
+ *
+ * Returns: The instruction encoding of the prior faulting instruction.
+ */
+int kvm_get_badinstrp(u32 *opc, struct kvm_vcpu *vcpu, u32 *out)
+{
+ if (cpu_has_badinstrp) {
+ *out = vcpu->arch.host_cp0_badinstrp;
+ return 0;
+ } else {
+ WARN_ONCE(1, "CPU doesn't have BadInstrp register\n");
+ return -EINVAL;
+ }
+}
+
+/**
+ * kvm_mips_count_disabled() - Find whether the CP0_Count timer is disabled.
+ * @vcpu: Virtual CPU.
+ *
+ * Returns: 1 if the CP0_Count timer is disabled by either the guest
+ * CP0_Cause.DC bit or the count_ctl.DC bit.
+ * 0 otherwise (in which case CP0_Count timer is running).
+ */
+int kvm_mips_count_disabled(struct kvm_vcpu *vcpu)
+{
+ struct mips_coproc *cop0 = &vcpu->arch.cop0;
+
+ return (vcpu->arch.count_ctl & KVM_REG_MIPS_COUNT_CTL_DC) ||
+ (kvm_read_c0_guest_cause(cop0) & CAUSEF_DC);
+}
+
+/**
+ * kvm_mips_ktime_to_count() - Scale ktime_t to a 32-bit count.
+ *
+ * Caches the dynamic nanosecond bias in vcpu->arch.count_dyn_bias.
+ *
+ * Assumes !kvm_mips_count_disabled(@vcpu) (guest CP0_Count timer is running).
+ */
+static u32 kvm_mips_ktime_to_count(struct kvm_vcpu *vcpu, ktime_t now)
+{
+ s64 now_ns, periods;
+ u64 delta;
+
+ now_ns = ktime_to_ns(now);
+ delta = now_ns + vcpu->arch.count_dyn_bias;
+
+ if (delta >= vcpu->arch.count_period) {
+ /* If delta is out of safe range the bias needs adjusting */
+ periods = div64_s64(now_ns, vcpu->arch.count_period);
+ vcpu->arch.count_dyn_bias = -periods * vcpu->arch.count_period;
+ /* Recalculate delta with new bias */
+ delta = now_ns + vcpu->arch.count_dyn_bias;
+ }
+
+ /*
+ * We've ensured that:
+ * delta < count_period
+ *
+ * Therefore the intermediate delta*count_hz will never overflow since
+ * at the boundary condition:
+ * delta = count_period
+ * delta = NSEC_PER_SEC * 2^32 / count_hz
+ * delta * count_hz = NSEC_PER_SEC * 2^32
+ */
+ return div_u64(delta * vcpu->arch.count_hz, NSEC_PER_SEC);
+}
+
+/**
+ * kvm_mips_count_time() - Get effective current time.
+ * @vcpu: Virtual CPU.
+ *
+ * Get effective monotonic ktime. This is usually a straightforward ktime_get(),
+ * except when the master disable bit is set in count_ctl, in which case it is
+ * count_resume, i.e. the time that the count was disabled.
+ *
+ * Returns: Effective monotonic ktime for CP0_Count.
+ */
+static inline ktime_t kvm_mips_count_time(struct kvm_vcpu *vcpu)
+{
+ if (unlikely(vcpu->arch.count_ctl & KVM_REG_MIPS_COUNT_CTL_DC))
+ return vcpu->arch.count_resume;
+
+ return ktime_get();
+}
+
+/**
+ * kvm_mips_read_count_running() - Read the current count value as if running.
+ * @vcpu: Virtual CPU.
+ * @now: Kernel time to read CP0_Count at.
+ *
+ * Returns the current guest CP0_Count register at time @now and handles if the
+ * timer interrupt is pending and hasn't been handled yet.
+ *
+ * Returns: The current value of the guest CP0_Count register.
+ */
+static u32 kvm_mips_read_count_running(struct kvm_vcpu *vcpu, ktime_t now)
+{
+ struct mips_coproc *cop0 = &vcpu->arch.cop0;
+ ktime_t expires, threshold;
+ u32 count, compare;
+ int running;
+
+ /* Calculate the biased and scaled guest CP0_Count */
+ count = vcpu->arch.count_bias + kvm_mips_ktime_to_count(vcpu, now);
+ compare = kvm_read_c0_guest_compare(cop0);
+
+ /*
+ * Find whether CP0_Count has reached the closest timer interrupt. If
+ * not, we shouldn't inject it.
+ */
+ if ((s32)(count - compare) < 0)
+ return count;
+
+ /*
+ * The CP0_Count we're going to return has already reached the closest
+ * timer interrupt. Quickly check if it really is a new interrupt by
+ * looking at whether the interval until the hrtimer expiry time is
+ * less than 1/4 of the timer period.
+ */
+ expires = hrtimer_get_expires(&vcpu->arch.comparecount_timer);
+ threshold = ktime_add_ns(now, vcpu->arch.count_period / 4);
+ if (ktime_before(expires, threshold)) {
+ /*
+ * Cancel it while we handle it so there's no chance of
+ * interference with the timeout handler.
+ */
+ running = hrtimer_cancel(&vcpu->arch.comparecount_timer);
+
+ /* Nothing should be waiting on the timeout */
+ kvm_mips_callbacks->queue_timer_int(vcpu);
+
+ /*
+ * Restart the timer if it was running based on the expiry time
+ * we read, so that we don't push it back 2 periods.
+ */
+ if (running) {
+ expires = ktime_add_ns(expires,
+ vcpu->arch.count_period);
+ hrtimer_start(&vcpu->arch.comparecount_timer, expires,
+ HRTIMER_MODE_ABS);
+ }
+ }
+
+ return count;
+}
+
+/**
+ * kvm_mips_read_count() - Read the current count value.
+ * @vcpu: Virtual CPU.
+ *
+ * Read the current guest CP0_Count value, taking into account whether the timer
+ * is stopped.
+ *
+ * Returns: The current guest CP0_Count value.
+ */
+u32 kvm_mips_read_count(struct kvm_vcpu *vcpu)
+{
+ struct mips_coproc *cop0 = &vcpu->arch.cop0;
+
+ /* If count disabled just read static copy of count */
+ if (kvm_mips_count_disabled(vcpu))
+ return kvm_read_c0_guest_count(cop0);
+
+ return kvm_mips_read_count_running(vcpu, ktime_get());
+}
+
+/**
+ * kvm_mips_freeze_hrtimer() - Safely stop the hrtimer.
+ * @vcpu: Virtual CPU.
+ * @count: Output pointer for CP0_Count value at point of freeze.
+ *
+ * Freeze the hrtimer safely and return both the ktime and the CP0_Count value
+ * at the point it was frozen. It is guaranteed that any pending interrupts at
+ * the point it was frozen are handled, and none after that point.
+ *
+ * This is useful where the time/CP0_Count is needed in the calculation of the
+ * new parameters.
+ *
+ * Assumes !kvm_mips_count_disabled(@vcpu) (guest CP0_Count timer is running).
+ *
+ * Returns: The ktime at the point of freeze.
+ */
+ktime_t kvm_mips_freeze_hrtimer(struct kvm_vcpu *vcpu, u32 *count)
+{
+ ktime_t now;
+
+ /* stop hrtimer before finding time */
+ hrtimer_cancel(&vcpu->arch.comparecount_timer);
+ now = ktime_get();
+
+ /* find count at this point and handle pending hrtimer */
+ *count = kvm_mips_read_count_running(vcpu, now);
+
+ return now;
+}
+
+/**
+ * kvm_mips_resume_hrtimer() - Resume hrtimer, updating expiry.
+ * @vcpu: Virtual CPU.
+ * @now: ktime at point of resume.
+ * @count: CP0_Count at point of resume.
+ *
+ * Resumes the timer and updates the timer expiry based on @now and @count.
+ * This can be used in conjunction with kvm_mips_freeze_timer() when timer
+ * parameters need to be changed.
+ *
+ * It is guaranteed that a timer interrupt immediately after resume will be
+ * handled, but not if CP_Compare is exactly at @count. That case is already
+ * handled by kvm_mips_freeze_timer().
+ *
+ * Assumes !kvm_mips_count_disabled(@vcpu) (guest CP0_Count timer is running).
+ */
+static void kvm_mips_resume_hrtimer(struct kvm_vcpu *vcpu,
+ ktime_t now, u32 count)
+{
+ struct mips_coproc *cop0 = &vcpu->arch.cop0;
+ u32 compare;
+ u64 delta;
+ ktime_t expire;
+
+ /* Calculate timeout (wrap 0 to 2^32) */
+ compare = kvm_read_c0_guest_compare(cop0);
+ delta = (u64)(u32)(compare - count - 1) + 1;
+ delta = div_u64(delta * NSEC_PER_SEC, vcpu->arch.count_hz);
+ expire = ktime_add_ns(now, delta);
+
+ /* Update hrtimer to use new timeout */
+ hrtimer_cancel(&vcpu->arch.comparecount_timer);
+ hrtimer_start(&vcpu->arch.comparecount_timer, expire, HRTIMER_MODE_ABS);
+}
+
+/**
+ * kvm_mips_restore_hrtimer() - Restore hrtimer after a gap, updating expiry.
+ * @vcpu: Virtual CPU.
+ * @before: Time before Count was saved, lower bound of drift calculation.
+ * @count: CP0_Count at point of restore.
+ * @min_drift: Minimum amount of drift permitted before correction.
+ * Must be <= 0.
+ *
+ * Restores the timer from a particular @count, accounting for drift. This can
+ * be used in conjunction with kvm_mips_freeze_timer() when a hardware timer is
+ * to be used for a period of time, but the exact ktime corresponding to the
+ * final Count that must be restored is not known.
+ *
+ * It is gauranteed that a timer interrupt immediately after restore will be
+ * handled, but not if CP0_Compare is exactly at @count. That case should
+ * already be handled when the hardware timer state is saved.
+ *
+ * Assumes !kvm_mips_count_disabled(@vcpu) (guest CP0_Count timer is not
+ * stopped).
+ *
+ * Returns: Amount of correction to count_bias due to drift.
+ */
+int kvm_mips_restore_hrtimer(struct kvm_vcpu *vcpu, ktime_t before,
+ u32 count, int min_drift)
+{
+ ktime_t now, count_time;
+ u32 now_count, before_count;
+ u64 delta;
+ int drift, ret = 0;
+
+ /* Calculate expected count at before */
+ before_count = vcpu->arch.count_bias +
+ kvm_mips_ktime_to_count(vcpu, before);
+
+ /*
+ * Detect significantly negative drift, where count is lower than
+ * expected. Some negative drift is expected when hardware counter is
+ * set after kvm_mips_freeze_timer(), and it is harmless to allow the
+ * time to jump forwards a little, within reason. If the drift is too
+ * significant, adjust the bias to avoid a big Guest.CP0_Count jump.
+ */
+ drift = count - before_count;
+ if (drift < min_drift) {
+ count_time = before;
+ vcpu->arch.count_bias += drift;
+ ret = drift;
+ goto resume;
+ }
+
+ /* Calculate expected count right now */
+ now = ktime_get();
+ now_count = vcpu->arch.count_bias + kvm_mips_ktime_to_count(vcpu, now);
+
+ /*
+ * Detect positive drift, where count is higher than expected, and
+ * adjust the bias to avoid guest time going backwards.
+ */
+ drift = count - now_count;
+ if (drift > 0) {
+ count_time = now;
+ vcpu->arch.count_bias += drift;
+ ret = drift;
+ goto resume;
+ }
+
+ /* Subtract nanosecond delta to find ktime when count was read */
+ delta = (u64)(u32)(now_count - count);
+ delta = div_u64(delta * NSEC_PER_SEC, vcpu->arch.count_hz);
+ count_time = ktime_sub_ns(now, delta);
+
+resume:
+ /* Resume using the calculated ktime */
+ kvm_mips_resume_hrtimer(vcpu, count_time, count);
+ return ret;
+}
+
+/**
+ * kvm_mips_write_count() - Modify the count and update timer.
+ * @vcpu: Virtual CPU.
+ * @count: Guest CP0_Count value to set.
+ *
+ * Sets the CP0_Count value and updates the timer accordingly.
+ */
+void kvm_mips_write_count(struct kvm_vcpu *vcpu, u32 count)
+{
+ struct mips_coproc *cop0 = &vcpu->arch.cop0;
+ ktime_t now;
+
+ /* Calculate bias */
+ now = kvm_mips_count_time(vcpu);
+ vcpu->arch.count_bias = count - kvm_mips_ktime_to_count(vcpu, now);
+
+ if (kvm_mips_count_disabled(vcpu))
+ /* The timer's disabled, adjust the static count */
+ kvm_write_c0_guest_count(cop0, count);
+ else
+ /* Update timeout */
+ kvm_mips_resume_hrtimer(vcpu, now, count);
+}
+
+/**
+ * kvm_mips_init_count() - Initialise timer.
+ * @vcpu: Virtual CPU.
+ * @count_hz: Frequency of timer.
+ *
+ * Initialise the timer to the specified frequency, zero it, and set it going if
+ * it's enabled.
+ */
+void kvm_mips_init_count(struct kvm_vcpu *vcpu, unsigned long count_hz)
+{
+ vcpu->arch.count_hz = count_hz;
+ vcpu->arch.count_period = div_u64((u64)NSEC_PER_SEC << 32, count_hz);
+ vcpu->arch.count_dyn_bias = 0;
+
+ /* Starting at 0 */
+ kvm_mips_write_count(vcpu, 0);
+}
+
+/**
+ * kvm_mips_set_count_hz() - Update the frequency of the timer.
+ * @vcpu: Virtual CPU.
+ * @count_hz: Frequency of CP0_Count timer in Hz.
+ *
+ * Change the frequency of the CP0_Count timer. This is done atomically so that
+ * CP0_Count is continuous and no timer interrupt is lost.
+ *
+ * Returns: -EINVAL if @count_hz is out of range.
+ * 0 on success.
+ */
+int kvm_mips_set_count_hz(struct kvm_vcpu *vcpu, s64 count_hz)
+{
+ struct mips_coproc *cop0 = &vcpu->arch.cop0;
+ int dc;
+ ktime_t now;
+ u32 count;
+
+ /* ensure the frequency is in a sensible range... */
+ if (count_hz <= 0 || count_hz > NSEC_PER_SEC)
+ return -EINVAL;
+ /* ... and has actually changed */
+ if (vcpu->arch.count_hz == count_hz)
+ return 0;
+
+ /* Safely freeze timer so we can keep it continuous */
+ dc = kvm_mips_count_disabled(vcpu);
+ if (dc) {
+ now = kvm_mips_count_time(vcpu);
+ count = kvm_read_c0_guest_count(cop0);
+ } else {
+ now = kvm_mips_freeze_hrtimer(vcpu, &count);
+ }
+
+ /* Update the frequency */
+ vcpu->arch.count_hz = count_hz;
+ vcpu->arch.count_period = div_u64((u64)NSEC_PER_SEC << 32, count_hz);
+ vcpu->arch.count_dyn_bias = 0;
+
+ /* Calculate adjusted bias so dynamic count is unchanged */
+ vcpu->arch.count_bias = count - kvm_mips_ktime_to_count(vcpu, now);
+
+ /* Update and resume hrtimer */
+ if (!dc)
+ kvm_mips_resume_hrtimer(vcpu, now, count);
+ return 0;
+}
+
+/**
+ * kvm_mips_write_compare() - Modify compare and update timer.
+ * @vcpu: Virtual CPU.
+ * @compare: New CP0_Compare value.
+ * @ack: Whether to acknowledge timer interrupt.
+ *
+ * Update CP0_Compare to a new value and update the timeout.
+ * If @ack, atomically acknowledge any pending timer interrupt, otherwise ensure
+ * any pending timer interrupt is preserved.
+ */
+void kvm_mips_write_compare(struct kvm_vcpu *vcpu, u32 compare, bool ack)
+{
+ struct mips_coproc *cop0 = &vcpu->arch.cop0;
+ int dc;
+ u32 old_compare = kvm_read_c0_guest_compare(cop0);
+ s32 delta = compare - old_compare;
+ u32 cause;
+ ktime_t now = ktime_set(0, 0); /* silence bogus GCC warning */
+ u32 count;
+
+ /* if unchanged, must just be an ack */
+ if (old_compare == compare) {
+ if (!ack)
+ return;
+ kvm_mips_callbacks->dequeue_timer_int(vcpu);
+ kvm_write_c0_guest_compare(cop0, compare);
+ return;
+ }
+
+ /*
+ * If guest CP0_Compare moves forward, CP0_GTOffset should be adjusted
+ * too to prevent guest CP0_Count hitting guest CP0_Compare.
+ *
+ * The new GTOffset corresponds to the new value of CP0_Compare, and is
+ * set prior to it being written into the guest context. We disable
+ * preemption until the new value is written to prevent restore of a
+ * GTOffset corresponding to the old CP0_Compare value.
+ */
+ if (delta > 0) {
+ preempt_disable();
+ write_c0_gtoffset(compare - read_c0_count());
+ back_to_back_c0_hazard();
+ }
+
+ /* freeze_hrtimer() takes care of timer interrupts <= count */
+ dc = kvm_mips_count_disabled(vcpu);
+ if (!dc)
+ now = kvm_mips_freeze_hrtimer(vcpu, &count);
+
+ if (ack)
+ kvm_mips_callbacks->dequeue_timer_int(vcpu);
+ else
+ /*
+ * With VZ, writing CP0_Compare acks (clears) CP0_Cause.TI, so
+ * preserve guest CP0_Cause.TI if we don't want to ack it.
+ */
+ cause = kvm_read_c0_guest_cause(cop0);
+
+ kvm_write_c0_guest_compare(cop0, compare);
+
+ if (delta > 0)
+ preempt_enable();
+
+ back_to_back_c0_hazard();
+
+ if (!ack && cause & CAUSEF_TI)
+ kvm_write_c0_guest_cause(cop0, cause);
+
+ /* resume_hrtimer() takes care of timer interrupts > count */
+ if (!dc)
+ kvm_mips_resume_hrtimer(vcpu, now, count);
+
+ /*
+ * If guest CP0_Compare is moving backward, we delay CP0_GTOffset change
+ * until after the new CP0_Compare is written, otherwise new guest
+ * CP0_Count could hit new guest CP0_Compare.
+ */
+ if (delta <= 0)
+ write_c0_gtoffset(compare - read_c0_count());
+}
+
+/**
+ * kvm_mips_count_disable() - Disable count.
+ * @vcpu: Virtual CPU.
+ *
+ * Disable the CP0_Count timer. A timer interrupt on or before the final stop
+ * time will be handled but not after.
+ *
+ * Assumes CP0_Count was previously enabled but now Guest.CP0_Cause.DC or
+ * count_ctl.DC has been set (count disabled).
+ *
+ * Returns: The time that the timer was stopped.
+ */
+static ktime_t kvm_mips_count_disable(struct kvm_vcpu *vcpu)
+{
+ struct mips_coproc *cop0 = &vcpu->arch.cop0;
+ u32 count;
+ ktime_t now;
+
+ /* Stop hrtimer */
+ hrtimer_cancel(&vcpu->arch.comparecount_timer);
+
+ /* Set the static count from the dynamic count, handling pending TI */
+ now = ktime_get();
+ count = kvm_mips_read_count_running(vcpu, now);
+ kvm_write_c0_guest_count(cop0, count);
+
+ return now;
+}
+
+/**
+ * kvm_mips_count_disable_cause() - Disable count using CP0_Cause.DC.
+ * @vcpu: Virtual CPU.
+ *
+ * Disable the CP0_Count timer and set CP0_Cause.DC. A timer interrupt on or
+ * before the final stop time will be handled if the timer isn't disabled by
+ * count_ctl.DC, but not after.
+ *
+ * Assumes CP0_Cause.DC is clear (count enabled).
+ */
+void kvm_mips_count_disable_cause(struct kvm_vcpu *vcpu)
+{
+ struct mips_coproc *cop0 = &vcpu->arch.cop0;
+
+ kvm_set_c0_guest_cause(cop0, CAUSEF_DC);
+ if (!(vcpu->arch.count_ctl & KVM_REG_MIPS_COUNT_CTL_DC))
+ kvm_mips_count_disable(vcpu);
+}
+
+/**
+ * kvm_mips_count_enable_cause() - Enable count using CP0_Cause.DC.
+ * @vcpu: Virtual CPU.
+ *
+ * Enable the CP0_Count timer and clear CP0_Cause.DC. A timer interrupt after
+ * the start time will be handled if the timer isn't disabled by count_ctl.DC,
+ * potentially before even returning, so the caller should be careful with
+ * ordering of CP0_Cause modifications so as not to lose it.
+ *
+ * Assumes CP0_Cause.DC is set (count disabled).
+ */
+void kvm_mips_count_enable_cause(struct kvm_vcpu *vcpu)
+{
+ struct mips_coproc *cop0 = &vcpu->arch.cop0;
+ u32 count;
+
+ kvm_clear_c0_guest_cause(cop0, CAUSEF_DC);
+
+ /*
+ * Set the dynamic count to match the static count.
+ * This starts the hrtimer if count_ctl.DC allows it.
+ * Otherwise it conveniently updates the biases.
+ */
+ count = kvm_read_c0_guest_count(cop0);
+ kvm_mips_write_count(vcpu, count);
+}
+
+/**
+ * kvm_mips_set_count_ctl() - Update the count control KVM register.
+ * @vcpu: Virtual CPU.
+ * @count_ctl: Count control register new value.
+ *
+ * Set the count control KVM register. The timer is updated accordingly.
+ *
+ * Returns: -EINVAL if reserved bits are set.
+ * 0 on success.
+ */
+int kvm_mips_set_count_ctl(struct kvm_vcpu *vcpu, s64 count_ctl)
+{
+ struct mips_coproc *cop0 = &vcpu->arch.cop0;
+ s64 changed = count_ctl ^ vcpu->arch.count_ctl;
+ s64 delta;
+ ktime_t expire, now;
+ u32 count, compare;
+
+ /* Only allow defined bits to be changed */
+ if (changed & ~(s64)(KVM_REG_MIPS_COUNT_CTL_DC))
+ return -EINVAL;
+
+ /* Apply new value */
+ vcpu->arch.count_ctl = count_ctl;
+
+ /* Master CP0_Count disable */
+ if (changed & KVM_REG_MIPS_COUNT_CTL_DC) {
+ /* Is CP0_Cause.DC already disabling CP0_Count? */
+ if (kvm_read_c0_guest_cause(cop0) & CAUSEF_DC) {
+ if (count_ctl & KVM_REG_MIPS_COUNT_CTL_DC)
+ /* Just record the current time */
+ vcpu->arch.count_resume = ktime_get();
+ } else if (count_ctl & KVM_REG_MIPS_COUNT_CTL_DC) {
+ /* disable timer and record current time */
+ vcpu->arch.count_resume = kvm_mips_count_disable(vcpu);
+ } else {
+ /*
+ * Calculate timeout relative to static count at resume
+ * time (wrap 0 to 2^32).
+ */
+ count = kvm_read_c0_guest_count(cop0);
+ compare = kvm_read_c0_guest_compare(cop0);
+ delta = (u64)(u32)(compare - count - 1) + 1;
+ delta = div_u64(delta * NSEC_PER_SEC,
+ vcpu->arch.count_hz);
+ expire = ktime_add_ns(vcpu->arch.count_resume, delta);
+
+ /* Handle pending interrupt */
+ now = ktime_get();
+ if (ktime_compare(now, expire) >= 0)
+ /* Nothing should be waiting on the timeout */
+ kvm_mips_callbacks->queue_timer_int(vcpu);
+
+ /* Resume hrtimer without changing bias */
+ count = kvm_mips_read_count_running(vcpu, now);
+ kvm_mips_resume_hrtimer(vcpu, now, count);
+ }
+ }
+
+ return 0;
+}
+
+/**
+ * kvm_mips_set_count_resume() - Update the count resume KVM register.
+ * @vcpu: Virtual CPU.
+ * @count_resume: Count resume register new value.
+ *
+ * Set the count resume KVM register.
+ *
+ * Returns: -EINVAL if out of valid range (0..now).
+ * 0 on success.
+ */
+int kvm_mips_set_count_resume(struct kvm_vcpu *vcpu, s64 count_resume)
+{
+ /*
+ * It doesn't make sense for the resume time to be in the future, as it
+ * would be possible for the next interrupt to be more than a full
+ * period in the future.
+ */
+ if (count_resume < 0 || count_resume > ktime_to_ns(ktime_get()))
+ return -EINVAL;
+
+ vcpu->arch.count_resume = ns_to_ktime(count_resume);
+ return 0;
+}
+
+/**
+ * kvm_mips_count_timeout() - Push timer forward on timeout.
+ * @vcpu: Virtual CPU.
+ *
+ * Handle an hrtimer event by push the hrtimer forward a period.
+ *
+ * Returns: The hrtimer_restart value to return to the hrtimer subsystem.
+ */
+enum hrtimer_restart kvm_mips_count_timeout(struct kvm_vcpu *vcpu)
+{
+ /* Add the Count period to the current expiry time */
+ hrtimer_add_expires_ns(&vcpu->arch.comparecount_timer,
+ vcpu->arch.count_period);
+ return HRTIMER_RESTART;
+}
+
+enum emulation_result kvm_mips_emul_wait(struct kvm_vcpu *vcpu)
+{
+ kvm_debug("[%#lx] !!!WAIT!!! (%#lx)\n", vcpu->arch.pc,
+ vcpu->arch.pending_exceptions);
+
+ ++vcpu->stat.wait_exits;
+ trace_kvm_exit(vcpu, KVM_TRACE_EXIT_WAIT);
+ if (!vcpu->arch.pending_exceptions) {
+ kvm_vz_lose_htimer(vcpu);
+ vcpu->arch.wait = 1;
+ kvm_vcpu_halt(vcpu);
+
+ /*
+ * We are runnable, then definitely go off to user space to
+ * check if any I/O interrupts are pending.
+ */
+ if (kvm_arch_vcpu_runnable(vcpu))
+ vcpu->run->exit_reason = KVM_EXIT_IRQ_WINDOW_OPEN;
+ }
+
+ return EMULATE_DONE;
+}
+
+enum emulation_result kvm_mips_emulate_store(union mips_instruction inst,
+ u32 cause,
+ struct kvm_vcpu *vcpu)
+{
+ int r;
+ enum emulation_result er;
+ u32 rt;
+ struct kvm_run *run = vcpu->run;
+ void *data = run->mmio.data;
+ unsigned int imme;
+ unsigned long curr_pc;
+
+ /*
+ * Update PC and hold onto current PC in case there is
+ * an error and we want to rollback the PC
+ */
+ curr_pc = vcpu->arch.pc;
+ er = update_pc(vcpu, cause);
+ if (er == EMULATE_FAIL)
+ return er;
+
+ rt = inst.i_format.rt;
+
+ run->mmio.phys_addr = kvm_mips_callbacks->gva_to_gpa(
+ vcpu->arch.host_cp0_badvaddr);
+ if (run->mmio.phys_addr == KVM_INVALID_ADDR)
+ goto out_fail;
+
+ switch (inst.i_format.opcode) {
+#if defined(CONFIG_64BIT)
+ case sd_op:
+ run->mmio.len = 8;
+ *(u64 *)data = vcpu->arch.gprs[rt];
+
+ kvm_debug("[%#lx] OP_SD: eaddr: %#lx, gpr: %#lx, data: %#llx\n",
+ vcpu->arch.pc, vcpu->arch.host_cp0_badvaddr,
+ vcpu->arch.gprs[rt], *(u64 *)data);
+ break;
+#endif
+
+ case sw_op:
+ run->mmio.len = 4;
+ *(u32 *)data = vcpu->arch.gprs[rt];
+
+ kvm_debug("[%#lx] OP_SW: eaddr: %#lx, gpr: %#lx, data: %#x\n",
+ vcpu->arch.pc, vcpu->arch.host_cp0_badvaddr,
+ vcpu->arch.gprs[rt], *(u32 *)data);
+ break;
+
+ case sh_op:
+ run->mmio.len = 2;
+ *(u16 *)data = vcpu->arch.gprs[rt];
+
+ kvm_debug("[%#lx] OP_SH: eaddr: %#lx, gpr: %#lx, data: %#x\n",
+ vcpu->arch.pc, vcpu->arch.host_cp0_badvaddr,
+ vcpu->arch.gprs[rt], *(u16 *)data);
+ break;
+
+ case sb_op:
+ run->mmio.len = 1;
+ *(u8 *)data = vcpu->arch.gprs[rt];
+
+ kvm_debug("[%#lx] OP_SB: eaddr: %#lx, gpr: %#lx, data: %#x\n",
+ vcpu->arch.pc, vcpu->arch.host_cp0_badvaddr,
+ vcpu->arch.gprs[rt], *(u8 *)data);
+ break;
+
+ case swl_op:
+ run->mmio.phys_addr = kvm_mips_callbacks->gva_to_gpa(
+ vcpu->arch.host_cp0_badvaddr) & (~0x3);
+ run->mmio.len = 4;
+ imme = vcpu->arch.host_cp0_badvaddr & 0x3;
+ switch (imme) {
+ case 0:
+ *(u32 *)data = ((*(u32 *)data) & 0xffffff00) |
+ (vcpu->arch.gprs[rt] >> 24);
+ break;
+ case 1:
+ *(u32 *)data = ((*(u32 *)data) & 0xffff0000) |
+ (vcpu->arch.gprs[rt] >> 16);
+ break;
+ case 2:
+ *(u32 *)data = ((*(u32 *)data) & 0xff000000) |
+ (vcpu->arch.gprs[rt] >> 8);
+ break;
+ case 3:
+ *(u32 *)data = vcpu->arch.gprs[rt];
+ break;
+ default:
+ break;
+ }
+
+ kvm_debug("[%#lx] OP_SWL: eaddr: %#lx, gpr: %#lx, data: %#x\n",
+ vcpu->arch.pc, vcpu->arch.host_cp0_badvaddr,
+ vcpu->arch.gprs[rt], *(u32 *)data);
+ break;
+
+ case swr_op:
+ run->mmio.phys_addr = kvm_mips_callbacks->gva_to_gpa(
+ vcpu->arch.host_cp0_badvaddr) & (~0x3);
+ run->mmio.len = 4;
+ imme = vcpu->arch.host_cp0_badvaddr & 0x3;
+ switch (imme) {
+ case 0:
+ *(u32 *)data = vcpu->arch.gprs[rt];
+ break;
+ case 1:
+ *(u32 *)data = ((*(u32 *)data) & 0xff) |
+ (vcpu->arch.gprs[rt] << 8);
+ break;
+ case 2:
+ *(u32 *)data = ((*(u32 *)data) & 0xffff) |
+ (vcpu->arch.gprs[rt] << 16);
+ break;
+ case 3:
+ *(u32 *)data = ((*(u32 *)data) & 0xffffff) |
+ (vcpu->arch.gprs[rt] << 24);
+ break;
+ default:
+ break;
+ }
+
+ kvm_debug("[%#lx] OP_SWR: eaddr: %#lx, gpr: %#lx, data: %#x\n",
+ vcpu->arch.pc, vcpu->arch.host_cp0_badvaddr,
+ vcpu->arch.gprs[rt], *(u32 *)data);
+ break;
+
+#if defined(CONFIG_64BIT)
+ case sdl_op:
+ run->mmio.phys_addr = kvm_mips_callbacks->gva_to_gpa(
+ vcpu->arch.host_cp0_badvaddr) & (~0x7);
+
+ run->mmio.len = 8;
+ imme = vcpu->arch.host_cp0_badvaddr & 0x7;
+ switch (imme) {
+ case 0:
+ *(u64 *)data = ((*(u64 *)data) & 0xffffffffffffff00) |
+ ((vcpu->arch.gprs[rt] >> 56) & 0xff);
+ break;
+ case 1:
+ *(u64 *)data = ((*(u64 *)data) & 0xffffffffffff0000) |
+ ((vcpu->arch.gprs[rt] >> 48) & 0xffff);
+ break;
+ case 2:
+ *(u64 *)data = ((*(u64 *)data) & 0xffffffffff000000) |
+ ((vcpu->arch.gprs[rt] >> 40) & 0xffffff);
+ break;
+ case 3:
+ *(u64 *)data = ((*(u64 *)data) & 0xffffffff00000000) |
+ ((vcpu->arch.gprs[rt] >> 32) & 0xffffffff);
+ break;
+ case 4:
+ *(u64 *)data = ((*(u64 *)data) & 0xffffff0000000000) |
+ ((vcpu->arch.gprs[rt] >> 24) & 0xffffffffff);
+ break;
+ case 5:
+ *(u64 *)data = ((*(u64 *)data) & 0xffff000000000000) |
+ ((vcpu->arch.gprs[rt] >> 16) & 0xffffffffffff);
+ break;
+ case 6:
+ *(u64 *)data = ((*(u64 *)data) & 0xff00000000000000) |
+ ((vcpu->arch.gprs[rt] >> 8) & 0xffffffffffffff);
+ break;
+ case 7:
+ *(u64 *)data = vcpu->arch.gprs[rt];
+ break;
+ default:
+ break;
+ }
+
+ kvm_debug("[%#lx] OP_SDL: eaddr: %#lx, gpr: %#lx, data: %llx\n",
+ vcpu->arch.pc, vcpu->arch.host_cp0_badvaddr,
+ vcpu->arch.gprs[rt], *(u64 *)data);
+ break;
+
+ case sdr_op:
+ run->mmio.phys_addr = kvm_mips_callbacks->gva_to_gpa(
+ vcpu->arch.host_cp0_badvaddr) & (~0x7);
+
+ run->mmio.len = 8;
+ imme = vcpu->arch.host_cp0_badvaddr & 0x7;
+ switch (imme) {
+ case 0:
+ *(u64 *)data = vcpu->arch.gprs[rt];
+ break;
+ case 1:
+ *(u64 *)data = ((*(u64 *)data) & 0xff) |
+ (vcpu->arch.gprs[rt] << 8);
+ break;
+ case 2:
+ *(u64 *)data = ((*(u64 *)data) & 0xffff) |
+ (vcpu->arch.gprs[rt] << 16);
+ break;
+ case 3:
+ *(u64 *)data = ((*(u64 *)data) & 0xffffff) |
+ (vcpu->arch.gprs[rt] << 24);
+ break;
+ case 4:
+ *(u64 *)data = ((*(u64 *)data) & 0xffffffff) |
+ (vcpu->arch.gprs[rt] << 32);
+ break;
+ case 5:
+ *(u64 *)data = ((*(u64 *)data) & 0xffffffffff) |
+ (vcpu->arch.gprs[rt] << 40);
+ break;
+ case 6:
+ *(u64 *)data = ((*(u64 *)data) & 0xffffffffffff) |
+ (vcpu->arch.gprs[rt] << 48);
+ break;
+ case 7:
+ *(u64 *)data = ((*(u64 *)data) & 0xffffffffffffff) |
+ (vcpu->arch.gprs[rt] << 56);
+ break;
+ default:
+ break;
+ }
+
+ kvm_debug("[%#lx] OP_SDR: eaddr: %#lx, gpr: %#lx, data: %llx\n",
+ vcpu->arch.pc, vcpu->arch.host_cp0_badvaddr,
+ vcpu->arch.gprs[rt], *(u64 *)data);
+ break;
+#endif
+
+#ifdef CONFIG_CPU_LOONGSON64
+ case sdc2_op:
+ rt = inst.loongson3_lsdc2_format.rt;
+ switch (inst.loongson3_lsdc2_format.opcode1) {
+ /*
+ * Loongson-3 overridden sdc2 instructions.
+ * opcode1 instruction
+ * 0x0 gssbx: store 1 bytes from GPR
+ * 0x1 gsshx: store 2 bytes from GPR
+ * 0x2 gsswx: store 4 bytes from GPR
+ * 0x3 gssdx: store 8 bytes from GPR
+ */
+ case 0x0:
+ run->mmio.len = 1;
+ *(u8 *)data = vcpu->arch.gprs[rt];
+
+ kvm_debug("[%#lx] OP_GSSBX: eaddr: %#lx, gpr: %#lx, data: %#x\n",
+ vcpu->arch.pc, vcpu->arch.host_cp0_badvaddr,
+ vcpu->arch.gprs[rt], *(u8 *)data);
+ break;
+ case 0x1:
+ run->mmio.len = 2;
+ *(u16 *)data = vcpu->arch.gprs[rt];
+
+ kvm_debug("[%#lx] OP_GSSSHX: eaddr: %#lx, gpr: %#lx, data: %#x\n",
+ vcpu->arch.pc, vcpu->arch.host_cp0_badvaddr,
+ vcpu->arch.gprs[rt], *(u16 *)data);
+ break;
+ case 0x2:
+ run->mmio.len = 4;
+ *(u32 *)data = vcpu->arch.gprs[rt];
+
+ kvm_debug("[%#lx] OP_GSSWX: eaddr: %#lx, gpr: %#lx, data: %#x\n",
+ vcpu->arch.pc, vcpu->arch.host_cp0_badvaddr,
+ vcpu->arch.gprs[rt], *(u32 *)data);
+ break;
+ case 0x3:
+ run->mmio.len = 8;
+ *(u64 *)data = vcpu->arch.gprs[rt];
+
+ kvm_debug("[%#lx] OP_GSSDX: eaddr: %#lx, gpr: %#lx, data: %#llx\n",
+ vcpu->arch.pc, vcpu->arch.host_cp0_badvaddr,
+ vcpu->arch.gprs[rt], *(u64 *)data);
+ break;
+ default:
+ kvm_err("Godson Extended GS-Store not yet supported (inst=0x%08x)\n",
+ inst.word);
+ break;
+ }
+ break;
+#endif
+ default:
+ kvm_err("Store not yet supported (inst=0x%08x)\n",
+ inst.word);
+ goto out_fail;
+ }
+
+ vcpu->mmio_needed = 1;
+ run->mmio.is_write = 1;
+ vcpu->mmio_is_write = 1;
+
+ r = kvm_io_bus_write(vcpu, KVM_MMIO_BUS,
+ run->mmio.phys_addr, run->mmio.len, data);
+
+ if (!r) {
+ vcpu->mmio_needed = 0;
+ return EMULATE_DONE;
+ }
+
+ return EMULATE_DO_MMIO;
+
+out_fail:
+ /* Rollback PC if emulation was unsuccessful */
+ vcpu->arch.pc = curr_pc;
+ return EMULATE_FAIL;
+}
+
+enum emulation_result kvm_mips_emulate_load(union mips_instruction inst,
+ u32 cause, struct kvm_vcpu *vcpu)
+{
+ struct kvm_run *run = vcpu->run;
+ int r;
+ enum emulation_result er;
+ unsigned long curr_pc;
+ u32 op, rt;
+ unsigned int imme;
+
+ rt = inst.i_format.rt;
+ op = inst.i_format.opcode;
+
+ /*
+ * Find the resume PC now while we have safe and easy access to the
+ * prior branch instruction, and save it for
+ * kvm_mips_complete_mmio_load() to restore later.
+ */
+ curr_pc = vcpu->arch.pc;
+ er = update_pc(vcpu, cause);
+ if (er == EMULATE_FAIL)
+ return er;
+ vcpu->arch.io_pc = vcpu->arch.pc;
+ vcpu->arch.pc = curr_pc;
+
+ vcpu->arch.io_gpr = rt;
+
+ run->mmio.phys_addr = kvm_mips_callbacks->gva_to_gpa(
+ vcpu->arch.host_cp0_badvaddr);
+ if (run->mmio.phys_addr == KVM_INVALID_ADDR)
+ return EMULATE_FAIL;
+
+ vcpu->mmio_needed = 2; /* signed */
+ switch (op) {
+#if defined(CONFIG_64BIT)
+ case ld_op:
+ run->mmio.len = 8;
+ break;
+
+ case lwu_op:
+ vcpu->mmio_needed = 1; /* unsigned */
+ fallthrough;
+#endif
+ case lw_op:
+ run->mmio.len = 4;
+ break;
+
+ case lhu_op:
+ vcpu->mmio_needed = 1; /* unsigned */
+ fallthrough;
+ case lh_op:
+ run->mmio.len = 2;
+ break;
+
+ case lbu_op:
+ vcpu->mmio_needed = 1; /* unsigned */
+ fallthrough;
+ case lb_op:
+ run->mmio.len = 1;
+ break;
+
+ case lwl_op:
+ run->mmio.phys_addr = kvm_mips_callbacks->gva_to_gpa(
+ vcpu->arch.host_cp0_badvaddr) & (~0x3);
+
+ run->mmio.len = 4;
+ imme = vcpu->arch.host_cp0_badvaddr & 0x3;
+ switch (imme) {
+ case 0:
+ vcpu->mmio_needed = 3; /* 1 byte */
+ break;
+ case 1:
+ vcpu->mmio_needed = 4; /* 2 bytes */
+ break;
+ case 2:
+ vcpu->mmio_needed = 5; /* 3 bytes */
+ break;
+ case 3:
+ vcpu->mmio_needed = 6; /* 4 bytes */
+ break;
+ default:
+ break;
+ }
+ break;
+
+ case lwr_op:
+ run->mmio.phys_addr = kvm_mips_callbacks->gva_to_gpa(
+ vcpu->arch.host_cp0_badvaddr) & (~0x3);
+
+ run->mmio.len = 4;
+ imme = vcpu->arch.host_cp0_badvaddr & 0x3;
+ switch (imme) {
+ case 0:
+ vcpu->mmio_needed = 7; /* 4 bytes */
+ break;
+ case 1:
+ vcpu->mmio_needed = 8; /* 3 bytes */
+ break;
+ case 2:
+ vcpu->mmio_needed = 9; /* 2 bytes */
+ break;
+ case 3:
+ vcpu->mmio_needed = 10; /* 1 byte */
+ break;
+ default:
+ break;
+ }
+ break;
+
+#if defined(CONFIG_64BIT)
+ case ldl_op:
+ run->mmio.phys_addr = kvm_mips_callbacks->gva_to_gpa(
+ vcpu->arch.host_cp0_badvaddr) & (~0x7);
+
+ run->mmio.len = 8;
+ imme = vcpu->arch.host_cp0_badvaddr & 0x7;
+ switch (imme) {
+ case 0:
+ vcpu->mmio_needed = 11; /* 1 byte */
+ break;
+ case 1:
+ vcpu->mmio_needed = 12; /* 2 bytes */
+ break;
+ case 2:
+ vcpu->mmio_needed = 13; /* 3 bytes */
+ break;
+ case 3:
+ vcpu->mmio_needed = 14; /* 4 bytes */
+ break;
+ case 4:
+ vcpu->mmio_needed = 15; /* 5 bytes */
+ break;
+ case 5:
+ vcpu->mmio_needed = 16; /* 6 bytes */
+ break;
+ case 6:
+ vcpu->mmio_needed = 17; /* 7 bytes */
+ break;
+ case 7:
+ vcpu->mmio_needed = 18; /* 8 bytes */
+ break;
+ default:
+ break;
+ }
+ break;
+
+ case ldr_op:
+ run->mmio.phys_addr = kvm_mips_callbacks->gva_to_gpa(
+ vcpu->arch.host_cp0_badvaddr) & (~0x7);
+
+ run->mmio.len = 8;
+ imme = vcpu->arch.host_cp0_badvaddr & 0x7;
+ switch (imme) {
+ case 0:
+ vcpu->mmio_needed = 19; /* 8 bytes */
+ break;
+ case 1:
+ vcpu->mmio_needed = 20; /* 7 bytes */
+ break;
+ case 2:
+ vcpu->mmio_needed = 21; /* 6 bytes */
+ break;
+ case 3:
+ vcpu->mmio_needed = 22; /* 5 bytes */
+ break;
+ case 4:
+ vcpu->mmio_needed = 23; /* 4 bytes */
+ break;
+ case 5:
+ vcpu->mmio_needed = 24; /* 3 bytes */
+ break;
+ case 6:
+ vcpu->mmio_needed = 25; /* 2 bytes */
+ break;
+ case 7:
+ vcpu->mmio_needed = 26; /* 1 byte */
+ break;
+ default:
+ break;
+ }
+ break;
+#endif
+
+#ifdef CONFIG_CPU_LOONGSON64
+ case ldc2_op:
+ rt = inst.loongson3_lsdc2_format.rt;
+ switch (inst.loongson3_lsdc2_format.opcode1) {
+ /*
+ * Loongson-3 overridden ldc2 instructions.
+ * opcode1 instruction
+ * 0x0 gslbx: store 1 bytes from GPR
+ * 0x1 gslhx: store 2 bytes from GPR
+ * 0x2 gslwx: store 4 bytes from GPR
+ * 0x3 gsldx: store 8 bytes from GPR
+ */
+ case 0x0:
+ run->mmio.len = 1;
+ vcpu->mmio_needed = 27; /* signed */
+ break;
+ case 0x1:
+ run->mmio.len = 2;
+ vcpu->mmio_needed = 28; /* signed */
+ break;
+ case 0x2:
+ run->mmio.len = 4;
+ vcpu->mmio_needed = 29; /* signed */
+ break;
+ case 0x3:
+ run->mmio.len = 8;
+ vcpu->mmio_needed = 30; /* signed */
+ break;
+ default:
+ kvm_err("Godson Extended GS-Load for float not yet supported (inst=0x%08x)\n",
+ inst.word);
+ break;
+ }
+ break;
+#endif
+
+ default:
+ kvm_err("Load not yet supported (inst=0x%08x)\n",
+ inst.word);
+ vcpu->mmio_needed = 0;
+ return EMULATE_FAIL;
+ }
+
+ run->mmio.is_write = 0;
+ vcpu->mmio_is_write = 0;
+
+ r = kvm_io_bus_read(vcpu, KVM_MMIO_BUS,
+ run->mmio.phys_addr, run->mmio.len, run->mmio.data);
+
+ if (!r) {
+ kvm_mips_complete_mmio_load(vcpu);
+ vcpu->mmio_needed = 0;
+ return EMULATE_DONE;
+ }
+
+ return EMULATE_DO_MMIO;
+}
+
+enum emulation_result kvm_mips_complete_mmio_load(struct kvm_vcpu *vcpu)
+{
+ struct kvm_run *run = vcpu->run;
+ unsigned long *gpr = &vcpu->arch.gprs[vcpu->arch.io_gpr];
+ enum emulation_result er = EMULATE_DONE;
+
+ if (run->mmio.len > sizeof(*gpr)) {
+ kvm_err("Bad MMIO length: %d", run->mmio.len);
+ er = EMULATE_FAIL;
+ goto done;
+ }
+
+ /* Restore saved resume PC */
+ vcpu->arch.pc = vcpu->arch.io_pc;
+
+ switch (run->mmio.len) {
+ case 8:
+ switch (vcpu->mmio_needed) {
+ case 11:
+ *gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xffffffffffffff) |
+ (((*(s64 *)run->mmio.data) & 0xff) << 56);
+ break;
+ case 12:
+ *gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xffffffffffff) |
+ (((*(s64 *)run->mmio.data) & 0xffff) << 48);
+ break;
+ case 13:
+ *gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xffffffffff) |
+ (((*(s64 *)run->mmio.data) & 0xffffff) << 40);
+ break;
+ case 14:
+ *gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xffffffff) |
+ (((*(s64 *)run->mmio.data) & 0xffffffff) << 32);
+ break;
+ case 15:
+ *gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xffffff) |
+ (((*(s64 *)run->mmio.data) & 0xffffffffff) << 24);
+ break;
+ case 16:
+ *gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xffff) |
+ (((*(s64 *)run->mmio.data) & 0xffffffffffff) << 16);
+ break;
+ case 17:
+ *gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xff) |
+ (((*(s64 *)run->mmio.data) & 0xffffffffffffff) << 8);
+ break;
+ case 18:
+ case 19:
+ *gpr = *(s64 *)run->mmio.data;
+ break;
+ case 20:
+ *gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xff00000000000000) |
+ ((((*(s64 *)run->mmio.data)) >> 8) & 0xffffffffffffff);
+ break;
+ case 21:
+ *gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xffff000000000000) |
+ ((((*(s64 *)run->mmio.data)) >> 16) & 0xffffffffffff);
+ break;
+ case 22:
+ *gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xffffff0000000000) |
+ ((((*(s64 *)run->mmio.data)) >> 24) & 0xffffffffff);
+ break;
+ case 23:
+ *gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xffffffff00000000) |
+ ((((*(s64 *)run->mmio.data)) >> 32) & 0xffffffff);
+ break;
+ case 24:
+ *gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xffffffffff000000) |
+ ((((*(s64 *)run->mmio.data)) >> 40) & 0xffffff);
+ break;
+ case 25:
+ *gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xffffffffffff0000) |
+ ((((*(s64 *)run->mmio.data)) >> 48) & 0xffff);
+ break;
+ case 26:
+ *gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xffffffffffffff00) |
+ ((((*(s64 *)run->mmio.data)) >> 56) & 0xff);
+ break;
+ default:
+ *gpr = *(s64 *)run->mmio.data;
+ }
+ break;
+
+ case 4:
+ switch (vcpu->mmio_needed) {
+ case 1:
+ *gpr = *(u32 *)run->mmio.data;
+ break;
+ case 2:
+ *gpr = *(s32 *)run->mmio.data;
+ break;
+ case 3:
+ *gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xffffff) |
+ (((*(s32 *)run->mmio.data) & 0xff) << 24);
+ break;
+ case 4:
+ *gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xffff) |
+ (((*(s32 *)run->mmio.data) & 0xffff) << 16);
+ break;
+ case 5:
+ *gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xff) |
+ (((*(s32 *)run->mmio.data) & 0xffffff) << 8);
+ break;
+ case 6:
+ case 7:
+ *gpr = *(s32 *)run->mmio.data;
+ break;
+ case 8:
+ *gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xff000000) |
+ ((((*(s32 *)run->mmio.data)) >> 8) & 0xffffff);
+ break;
+ case 9:
+ *gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xffff0000) |
+ ((((*(s32 *)run->mmio.data)) >> 16) & 0xffff);
+ break;
+ case 10:
+ *gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xffffff00) |
+ ((((*(s32 *)run->mmio.data)) >> 24) & 0xff);
+ break;
+ default:
+ *gpr = *(s32 *)run->mmio.data;
+ }
+ break;
+
+ case 2:
+ if (vcpu->mmio_needed == 1)
+ *gpr = *(u16 *)run->mmio.data;
+ else
+ *gpr = *(s16 *)run->mmio.data;
+
+ break;
+ case 1:
+ if (vcpu->mmio_needed == 1)
+ *gpr = *(u8 *)run->mmio.data;
+ else
+ *gpr = *(s8 *)run->mmio.data;
+ break;
+ }
+
+done:
+ return er;
+}