![Marcelo Tosatti](/assets/img/avatar_default.png)
Limit PIT timer frequency similarly to the limit applied by LAPIC timer. Cc: stable@kernel.org Reviewed-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
776 lines
19 KiB
C
776 lines
19 KiB
C
/*
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* 8253/8254 interval timer emulation
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*
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* Copyright (c) 2003-2004 Fabrice Bellard
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* Copyright (c) 2006 Intel Corporation
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* Copyright (c) 2007 Keir Fraser, XenSource Inc
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* Copyright (c) 2008 Intel Corporation
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* Copyright 2009 Red Hat, Inc. and/or its affiliates.
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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* in the Software without restriction, including without limitation the rights
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* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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* THE SOFTWARE.
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*
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* Authors:
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* Sheng Yang <sheng.yang@intel.com>
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* Based on QEMU and Xen.
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*/
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#define pr_fmt(fmt) "pit: " fmt
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#include <linux/kvm_host.h>
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#include <linux/slab.h>
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#include "irq.h"
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#include "i8254.h"
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#include "x86.h"
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#ifndef CONFIG_X86_64
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#define mod_64(x, y) ((x) - (y) * div64_u64(x, y))
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#else
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#define mod_64(x, y) ((x) % (y))
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#endif
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#define RW_STATE_LSB 1
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#define RW_STATE_MSB 2
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#define RW_STATE_WORD0 3
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#define RW_STATE_WORD1 4
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/* Compute with 96 bit intermediate result: (a*b)/c */
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static u64 muldiv64(u64 a, u32 b, u32 c)
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{
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union {
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u64 ll;
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struct {
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u32 low, high;
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} l;
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} u, res;
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u64 rl, rh;
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u.ll = a;
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rl = (u64)u.l.low * (u64)b;
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rh = (u64)u.l.high * (u64)b;
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rh += (rl >> 32);
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res.l.high = div64_u64(rh, c);
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res.l.low = div64_u64(((mod_64(rh, c) << 32) + (rl & 0xffffffff)), c);
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return res.ll;
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}
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static void pit_set_gate(struct kvm *kvm, int channel, u32 val)
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{
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struct kvm_kpit_channel_state *c =
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&kvm->arch.vpit->pit_state.channels[channel];
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WARN_ON(!mutex_is_locked(&kvm->arch.vpit->pit_state.lock));
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switch (c->mode) {
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default:
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case 0:
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case 4:
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/* XXX: just disable/enable counting */
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break;
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case 1:
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case 2:
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case 3:
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case 5:
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/* Restart counting on rising edge. */
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if (c->gate < val)
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c->count_load_time = ktime_get();
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break;
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}
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c->gate = val;
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}
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static int pit_get_gate(struct kvm *kvm, int channel)
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{
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WARN_ON(!mutex_is_locked(&kvm->arch.vpit->pit_state.lock));
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return kvm->arch.vpit->pit_state.channels[channel].gate;
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}
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static s64 __kpit_elapsed(struct kvm *kvm)
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{
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s64 elapsed;
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ktime_t remaining;
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struct kvm_kpit_state *ps = &kvm->arch.vpit->pit_state;
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if (!ps->period)
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return 0;
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/*
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* The Counter does not stop when it reaches zero. In
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* Modes 0, 1, 4, and 5 the Counter ``wraps around'' to
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* the highest count, either FFFF hex for binary counting
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* or 9999 for BCD counting, and continues counting.
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* Modes 2 and 3 are periodic; the Counter reloads
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* itself with the initial count and continues counting
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* from there.
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*/
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remaining = hrtimer_get_remaining(&ps->timer);
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elapsed = ps->period - ktime_to_ns(remaining);
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return elapsed;
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}
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static s64 kpit_elapsed(struct kvm *kvm, struct kvm_kpit_channel_state *c,
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int channel)
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{
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if (channel == 0)
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return __kpit_elapsed(kvm);
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return ktime_to_ns(ktime_sub(ktime_get(), c->count_load_time));
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}
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static int pit_get_count(struct kvm *kvm, int channel)
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{
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struct kvm_kpit_channel_state *c =
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&kvm->arch.vpit->pit_state.channels[channel];
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s64 d, t;
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int counter;
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WARN_ON(!mutex_is_locked(&kvm->arch.vpit->pit_state.lock));
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t = kpit_elapsed(kvm, c, channel);
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d = muldiv64(t, KVM_PIT_FREQ, NSEC_PER_SEC);
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switch (c->mode) {
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case 0:
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case 1:
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case 4:
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case 5:
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counter = (c->count - d) & 0xffff;
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break;
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case 3:
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/* XXX: may be incorrect for odd counts */
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counter = c->count - (mod_64((2 * d), c->count));
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break;
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default:
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counter = c->count - mod_64(d, c->count);
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break;
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}
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return counter;
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}
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static int pit_get_out(struct kvm *kvm, int channel)
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{
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struct kvm_kpit_channel_state *c =
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&kvm->arch.vpit->pit_state.channels[channel];
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s64 d, t;
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int out;
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WARN_ON(!mutex_is_locked(&kvm->arch.vpit->pit_state.lock));
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t = kpit_elapsed(kvm, c, channel);
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d = muldiv64(t, KVM_PIT_FREQ, NSEC_PER_SEC);
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switch (c->mode) {
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default:
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case 0:
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out = (d >= c->count);
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break;
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case 1:
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out = (d < c->count);
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break;
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case 2:
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out = ((mod_64(d, c->count) == 0) && (d != 0));
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break;
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case 3:
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out = (mod_64(d, c->count) < ((c->count + 1) >> 1));
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break;
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case 4:
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case 5:
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out = (d == c->count);
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break;
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}
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return out;
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}
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static void pit_latch_count(struct kvm *kvm, int channel)
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{
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struct kvm_kpit_channel_state *c =
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&kvm->arch.vpit->pit_state.channels[channel];
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WARN_ON(!mutex_is_locked(&kvm->arch.vpit->pit_state.lock));
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if (!c->count_latched) {
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c->latched_count = pit_get_count(kvm, channel);
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c->count_latched = c->rw_mode;
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}
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}
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static void pit_latch_status(struct kvm *kvm, int channel)
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{
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struct kvm_kpit_channel_state *c =
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&kvm->arch.vpit->pit_state.channels[channel];
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WARN_ON(!mutex_is_locked(&kvm->arch.vpit->pit_state.lock));
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if (!c->status_latched) {
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/* TODO: Return NULL COUNT (bit 6). */
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c->status = ((pit_get_out(kvm, channel) << 7) |
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(c->rw_mode << 4) |
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(c->mode << 1) |
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c->bcd);
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c->status_latched = 1;
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}
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}
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static void kvm_pit_ack_irq(struct kvm_irq_ack_notifier *kian)
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{
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struct kvm_kpit_state *ps = container_of(kian, struct kvm_kpit_state,
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irq_ack_notifier);
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int value;
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spin_lock(&ps->inject_lock);
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value = atomic_dec_return(&ps->pending);
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if (value < 0)
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/* spurious acks can be generated if, for example, the
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* PIC is being reset. Handle it gracefully here
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*/
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atomic_inc(&ps->pending);
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else if (value > 0)
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/* in this case, we had multiple outstanding pit interrupts
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* that we needed to inject. Reinject
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*/
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queue_kthread_work(&ps->pit->worker, &ps->pit->expired);
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ps->irq_ack = 1;
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spin_unlock(&ps->inject_lock);
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}
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void __kvm_migrate_pit_timer(struct kvm_vcpu *vcpu)
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{
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struct kvm_pit *pit = vcpu->kvm->arch.vpit;
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struct hrtimer *timer;
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if (!kvm_vcpu_is_bsp(vcpu) || !pit)
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return;
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timer = &pit->pit_state.timer;
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if (hrtimer_cancel(timer))
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hrtimer_start_expires(timer, HRTIMER_MODE_ABS);
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}
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static void destroy_pit_timer(struct kvm_pit *pit)
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{
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hrtimer_cancel(&pit->pit_state.timer);
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flush_kthread_work(&pit->expired);
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}
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static void pit_do_work(struct kthread_work *work)
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{
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struct kvm_pit *pit = container_of(work, struct kvm_pit, expired);
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struct kvm *kvm = pit->kvm;
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struct kvm_vcpu *vcpu;
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int i;
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struct kvm_kpit_state *ps = &pit->pit_state;
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int inject = 0;
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/* Try to inject pending interrupts when
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* last one has been acked.
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*/
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spin_lock(&ps->inject_lock);
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if (ps->irq_ack) {
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ps->irq_ack = 0;
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inject = 1;
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}
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spin_unlock(&ps->inject_lock);
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if (inject) {
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kvm_set_irq(kvm, kvm->arch.vpit->irq_source_id, 0, 1, false);
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kvm_set_irq(kvm, kvm->arch.vpit->irq_source_id, 0, 0, false);
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/*
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* Provides NMI watchdog support via Virtual Wire mode.
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* The route is: PIT -> PIC -> LVT0 in NMI mode.
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*
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* Note: Our Virtual Wire implementation is simplified, only
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* propagating PIT interrupts to all VCPUs when they have set
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* LVT0 to NMI delivery. Other PIC interrupts are just sent to
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* VCPU0, and only if its LVT0 is in EXTINT mode.
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*/
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if (kvm->arch.vapics_in_nmi_mode > 0)
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kvm_for_each_vcpu(i, vcpu, kvm)
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kvm_apic_nmi_wd_deliver(vcpu);
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}
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}
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static enum hrtimer_restart pit_timer_fn(struct hrtimer *data)
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{
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struct kvm_kpit_state *ps = container_of(data, struct kvm_kpit_state, timer);
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struct kvm_pit *pt = ps->kvm->arch.vpit;
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if (ps->reinject || !atomic_read(&ps->pending)) {
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atomic_inc(&ps->pending);
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queue_kthread_work(&pt->worker, &pt->expired);
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}
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if (ps->is_periodic) {
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hrtimer_add_expires_ns(&ps->timer, ps->period);
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return HRTIMER_RESTART;
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} else
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return HRTIMER_NORESTART;
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}
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static void create_pit_timer(struct kvm *kvm, u32 val, int is_period)
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{
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struct kvm_kpit_state *ps = &kvm->arch.vpit->pit_state;
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s64 interval;
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if (!irqchip_in_kernel(kvm) || ps->flags & KVM_PIT_FLAGS_HPET_LEGACY)
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return;
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interval = muldiv64(val, NSEC_PER_SEC, KVM_PIT_FREQ);
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pr_debug("create pit timer, interval is %llu nsec\n", interval);
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/* TODO The new value only affected after the retriggered */
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hrtimer_cancel(&ps->timer);
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flush_kthread_work(&ps->pit->expired);
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ps->period = interval;
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ps->is_periodic = is_period;
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ps->timer.function = pit_timer_fn;
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ps->kvm = ps->pit->kvm;
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atomic_set(&ps->pending, 0);
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ps->irq_ack = 1;
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/*
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* Do not allow the guest to program periodic timers with small
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* interval, since the hrtimers are not throttled by the host
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* scheduler.
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*/
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if (ps->is_periodic) {
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s64 min_period = min_timer_period_us * 1000LL;
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if (ps->period < min_period) {
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pr_info_ratelimited(
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"kvm: requested %lld ns "
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"i8254 timer period limited to %lld ns\n",
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ps->period, min_period);
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ps->period = min_period;
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}
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}
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hrtimer_start(&ps->timer, ktime_add_ns(ktime_get(), interval),
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HRTIMER_MODE_ABS);
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}
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static void pit_load_count(struct kvm *kvm, int channel, u32 val)
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{
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struct kvm_kpit_state *ps = &kvm->arch.vpit->pit_state;
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WARN_ON(!mutex_is_locked(&ps->lock));
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pr_debug("load_count val is %d, channel is %d\n", val, channel);
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/*
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* The largest possible initial count is 0; this is equivalent
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* to 216 for binary counting and 104 for BCD counting.
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*/
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if (val == 0)
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val = 0x10000;
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ps->channels[channel].count = val;
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if (channel != 0) {
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ps->channels[channel].count_load_time = ktime_get();
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return;
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}
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/* Two types of timer
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* mode 1 is one shot, mode 2 is period, otherwise del timer */
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switch (ps->channels[0].mode) {
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case 0:
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case 1:
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/* FIXME: enhance mode 4 precision */
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case 4:
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create_pit_timer(kvm, val, 0);
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break;
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case 2:
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case 3:
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create_pit_timer(kvm, val, 1);
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break;
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default:
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destroy_pit_timer(kvm->arch.vpit);
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}
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}
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void kvm_pit_load_count(struct kvm *kvm, int channel, u32 val, int hpet_legacy_start)
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{
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u8 saved_mode;
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if (hpet_legacy_start) {
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/* save existing mode for later reenablement */
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saved_mode = kvm->arch.vpit->pit_state.channels[0].mode;
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kvm->arch.vpit->pit_state.channels[0].mode = 0xff; /* disable timer */
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pit_load_count(kvm, channel, val);
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kvm->arch.vpit->pit_state.channels[0].mode = saved_mode;
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} else {
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pit_load_count(kvm, channel, val);
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}
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}
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static inline struct kvm_pit *dev_to_pit(struct kvm_io_device *dev)
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{
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return container_of(dev, struct kvm_pit, dev);
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}
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static inline struct kvm_pit *speaker_to_pit(struct kvm_io_device *dev)
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{
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return container_of(dev, struct kvm_pit, speaker_dev);
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}
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static inline int pit_in_range(gpa_t addr)
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{
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return ((addr >= KVM_PIT_BASE_ADDRESS) &&
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(addr < KVM_PIT_BASE_ADDRESS + KVM_PIT_MEM_LENGTH));
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}
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static int pit_ioport_write(struct kvm_io_device *this,
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gpa_t addr, int len, const void *data)
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{
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struct kvm_pit *pit = dev_to_pit(this);
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struct kvm_kpit_state *pit_state = &pit->pit_state;
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struct kvm *kvm = pit->kvm;
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int channel, access;
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struct kvm_kpit_channel_state *s;
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u32 val = *(u32 *) data;
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if (!pit_in_range(addr))
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return -EOPNOTSUPP;
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val &= 0xff;
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addr &= KVM_PIT_CHANNEL_MASK;
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mutex_lock(&pit_state->lock);
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if (val != 0)
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pr_debug("write addr is 0x%x, len is %d, val is 0x%x\n",
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(unsigned int)addr, len, val);
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if (addr == 3) {
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channel = val >> 6;
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if (channel == 3) {
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/* Read-Back Command. */
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for (channel = 0; channel < 3; channel++) {
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s = &pit_state->channels[channel];
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if (val & (2 << channel)) {
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if (!(val & 0x20))
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pit_latch_count(kvm, channel);
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if (!(val & 0x10))
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pit_latch_status(kvm, channel);
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}
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}
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} else {
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/* Select Counter <channel>. */
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s = &pit_state->channels[channel];
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access = (val >> 4) & KVM_PIT_CHANNEL_MASK;
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if (access == 0) {
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pit_latch_count(kvm, channel);
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} else {
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s->rw_mode = access;
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s->read_state = access;
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s->write_state = access;
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s->mode = (val >> 1) & 7;
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if (s->mode > 5)
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s->mode -= 4;
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s->bcd = val & 1;
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}
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}
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} else {
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/* Write Count. */
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s = &pit_state->channels[addr];
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switch (s->write_state) {
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default:
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case RW_STATE_LSB:
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pit_load_count(kvm, addr, val);
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break;
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case RW_STATE_MSB:
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pit_load_count(kvm, addr, val << 8);
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break;
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|
case RW_STATE_WORD0:
|
|
s->write_latch = val;
|
|
s->write_state = RW_STATE_WORD1;
|
|
break;
|
|
case RW_STATE_WORD1:
|
|
pit_load_count(kvm, addr, s->write_latch | (val << 8));
|
|
s->write_state = RW_STATE_WORD0;
|
|
break;
|
|
}
|
|
}
|
|
|
|
mutex_unlock(&pit_state->lock);
|
|
return 0;
|
|
}
|
|
|
|
static int pit_ioport_read(struct kvm_io_device *this,
|
|
gpa_t addr, int len, void *data)
|
|
{
|
|
struct kvm_pit *pit = dev_to_pit(this);
|
|
struct kvm_kpit_state *pit_state = &pit->pit_state;
|
|
struct kvm *kvm = pit->kvm;
|
|
int ret, count;
|
|
struct kvm_kpit_channel_state *s;
|
|
if (!pit_in_range(addr))
|
|
return -EOPNOTSUPP;
|
|
|
|
addr &= KVM_PIT_CHANNEL_MASK;
|
|
if (addr == 3)
|
|
return 0;
|
|
|
|
s = &pit_state->channels[addr];
|
|
|
|
mutex_lock(&pit_state->lock);
|
|
|
|
if (s->status_latched) {
|
|
s->status_latched = 0;
|
|
ret = s->status;
|
|
} else if (s->count_latched) {
|
|
switch (s->count_latched) {
|
|
default:
|
|
case RW_STATE_LSB:
|
|
ret = s->latched_count & 0xff;
|
|
s->count_latched = 0;
|
|
break;
|
|
case RW_STATE_MSB:
|
|
ret = s->latched_count >> 8;
|
|
s->count_latched = 0;
|
|
break;
|
|
case RW_STATE_WORD0:
|
|
ret = s->latched_count & 0xff;
|
|
s->count_latched = RW_STATE_MSB;
|
|
break;
|
|
}
|
|
} else {
|
|
switch (s->read_state) {
|
|
default:
|
|
case RW_STATE_LSB:
|
|
count = pit_get_count(kvm, addr);
|
|
ret = count & 0xff;
|
|
break;
|
|
case RW_STATE_MSB:
|
|
count = pit_get_count(kvm, addr);
|
|
ret = (count >> 8) & 0xff;
|
|
break;
|
|
case RW_STATE_WORD0:
|
|
count = pit_get_count(kvm, addr);
|
|
ret = count & 0xff;
|
|
s->read_state = RW_STATE_WORD1;
|
|
break;
|
|
case RW_STATE_WORD1:
|
|
count = pit_get_count(kvm, addr);
|
|
ret = (count >> 8) & 0xff;
|
|
s->read_state = RW_STATE_WORD0;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (len > sizeof(ret))
|
|
len = sizeof(ret);
|
|
memcpy(data, (char *)&ret, len);
|
|
|
|
mutex_unlock(&pit_state->lock);
|
|
return 0;
|
|
}
|
|
|
|
static int speaker_ioport_write(struct kvm_io_device *this,
|
|
gpa_t addr, int len, const void *data)
|
|
{
|
|
struct kvm_pit *pit = speaker_to_pit(this);
|
|
struct kvm_kpit_state *pit_state = &pit->pit_state;
|
|
struct kvm *kvm = pit->kvm;
|
|
u32 val = *(u32 *) data;
|
|
if (addr != KVM_SPEAKER_BASE_ADDRESS)
|
|
return -EOPNOTSUPP;
|
|
|
|
mutex_lock(&pit_state->lock);
|
|
pit_state->speaker_data_on = (val >> 1) & 1;
|
|
pit_set_gate(kvm, 2, val & 1);
|
|
mutex_unlock(&pit_state->lock);
|
|
return 0;
|
|
}
|
|
|
|
static int speaker_ioport_read(struct kvm_io_device *this,
|
|
gpa_t addr, int len, void *data)
|
|
{
|
|
struct kvm_pit *pit = speaker_to_pit(this);
|
|
struct kvm_kpit_state *pit_state = &pit->pit_state;
|
|
struct kvm *kvm = pit->kvm;
|
|
unsigned int refresh_clock;
|
|
int ret;
|
|
if (addr != KVM_SPEAKER_BASE_ADDRESS)
|
|
return -EOPNOTSUPP;
|
|
|
|
/* Refresh clock toggles at about 15us. We approximate as 2^14ns. */
|
|
refresh_clock = ((unsigned int)ktime_to_ns(ktime_get()) >> 14) & 1;
|
|
|
|
mutex_lock(&pit_state->lock);
|
|
ret = ((pit_state->speaker_data_on << 1) | pit_get_gate(kvm, 2) |
|
|
(pit_get_out(kvm, 2) << 5) | (refresh_clock << 4));
|
|
if (len > sizeof(ret))
|
|
len = sizeof(ret);
|
|
memcpy(data, (char *)&ret, len);
|
|
mutex_unlock(&pit_state->lock);
|
|
return 0;
|
|
}
|
|
|
|
void kvm_pit_reset(struct kvm_pit *pit)
|
|
{
|
|
int i;
|
|
struct kvm_kpit_channel_state *c;
|
|
|
|
mutex_lock(&pit->pit_state.lock);
|
|
pit->pit_state.flags = 0;
|
|
for (i = 0; i < 3; i++) {
|
|
c = &pit->pit_state.channels[i];
|
|
c->mode = 0xff;
|
|
c->gate = (i != 2);
|
|
pit_load_count(pit->kvm, i, 0);
|
|
}
|
|
mutex_unlock(&pit->pit_state.lock);
|
|
|
|
atomic_set(&pit->pit_state.pending, 0);
|
|
pit->pit_state.irq_ack = 1;
|
|
}
|
|
|
|
static void pit_mask_notifer(struct kvm_irq_mask_notifier *kimn, bool mask)
|
|
{
|
|
struct kvm_pit *pit = container_of(kimn, struct kvm_pit, mask_notifier);
|
|
|
|
if (!mask) {
|
|
atomic_set(&pit->pit_state.pending, 0);
|
|
pit->pit_state.irq_ack = 1;
|
|
}
|
|
}
|
|
|
|
static const struct kvm_io_device_ops pit_dev_ops = {
|
|
.read = pit_ioport_read,
|
|
.write = pit_ioport_write,
|
|
};
|
|
|
|
static const struct kvm_io_device_ops speaker_dev_ops = {
|
|
.read = speaker_ioport_read,
|
|
.write = speaker_ioport_write,
|
|
};
|
|
|
|
/* Caller must hold slots_lock */
|
|
struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags)
|
|
{
|
|
struct kvm_pit *pit;
|
|
struct kvm_kpit_state *pit_state;
|
|
struct pid *pid;
|
|
pid_t pid_nr;
|
|
int ret;
|
|
|
|
pit = kzalloc(sizeof(struct kvm_pit), GFP_KERNEL);
|
|
if (!pit)
|
|
return NULL;
|
|
|
|
pit->irq_source_id = kvm_request_irq_source_id(kvm);
|
|
if (pit->irq_source_id < 0) {
|
|
kfree(pit);
|
|
return NULL;
|
|
}
|
|
|
|
mutex_init(&pit->pit_state.lock);
|
|
mutex_lock(&pit->pit_state.lock);
|
|
spin_lock_init(&pit->pit_state.inject_lock);
|
|
|
|
pid = get_pid(task_tgid(current));
|
|
pid_nr = pid_vnr(pid);
|
|
put_pid(pid);
|
|
|
|
init_kthread_worker(&pit->worker);
|
|
pit->worker_task = kthread_run(kthread_worker_fn, &pit->worker,
|
|
"kvm-pit/%d", pid_nr);
|
|
if (IS_ERR(pit->worker_task)) {
|
|
mutex_unlock(&pit->pit_state.lock);
|
|
kvm_free_irq_source_id(kvm, pit->irq_source_id);
|
|
kfree(pit);
|
|
return NULL;
|
|
}
|
|
init_kthread_work(&pit->expired, pit_do_work);
|
|
|
|
kvm->arch.vpit = pit;
|
|
pit->kvm = kvm;
|
|
|
|
pit_state = &pit->pit_state;
|
|
pit_state->pit = pit;
|
|
hrtimer_init(&pit_state->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
|
|
pit_state->irq_ack_notifier.gsi = 0;
|
|
pit_state->irq_ack_notifier.irq_acked = kvm_pit_ack_irq;
|
|
kvm_register_irq_ack_notifier(kvm, &pit_state->irq_ack_notifier);
|
|
pit_state->reinject = true;
|
|
mutex_unlock(&pit->pit_state.lock);
|
|
|
|
kvm_pit_reset(pit);
|
|
|
|
pit->mask_notifier.func = pit_mask_notifer;
|
|
kvm_register_irq_mask_notifier(kvm, 0, &pit->mask_notifier);
|
|
|
|
kvm_iodevice_init(&pit->dev, &pit_dev_ops);
|
|
ret = kvm_io_bus_register_dev(kvm, KVM_PIO_BUS, KVM_PIT_BASE_ADDRESS,
|
|
KVM_PIT_MEM_LENGTH, &pit->dev);
|
|
if (ret < 0)
|
|
goto fail;
|
|
|
|
if (flags & KVM_PIT_SPEAKER_DUMMY) {
|
|
kvm_iodevice_init(&pit->speaker_dev, &speaker_dev_ops);
|
|
ret = kvm_io_bus_register_dev(kvm, KVM_PIO_BUS,
|
|
KVM_SPEAKER_BASE_ADDRESS, 4,
|
|
&pit->speaker_dev);
|
|
if (ret < 0)
|
|
goto fail_unregister;
|
|
}
|
|
|
|
return pit;
|
|
|
|
fail_unregister:
|
|
kvm_io_bus_unregister_dev(kvm, KVM_PIO_BUS, &pit->dev);
|
|
|
|
fail:
|
|
kvm_unregister_irq_mask_notifier(kvm, 0, &pit->mask_notifier);
|
|
kvm_unregister_irq_ack_notifier(kvm, &pit_state->irq_ack_notifier);
|
|
kvm_free_irq_source_id(kvm, pit->irq_source_id);
|
|
kthread_stop(pit->worker_task);
|
|
kfree(pit);
|
|
return NULL;
|
|
}
|
|
|
|
void kvm_free_pit(struct kvm *kvm)
|
|
{
|
|
struct hrtimer *timer;
|
|
|
|
if (kvm->arch.vpit) {
|
|
kvm_io_bus_unregister_dev(kvm, KVM_PIO_BUS, &kvm->arch.vpit->dev);
|
|
kvm_io_bus_unregister_dev(kvm, KVM_PIO_BUS,
|
|
&kvm->arch.vpit->speaker_dev);
|
|
kvm_unregister_irq_mask_notifier(kvm, 0,
|
|
&kvm->arch.vpit->mask_notifier);
|
|
kvm_unregister_irq_ack_notifier(kvm,
|
|
&kvm->arch.vpit->pit_state.irq_ack_notifier);
|
|
mutex_lock(&kvm->arch.vpit->pit_state.lock);
|
|
timer = &kvm->arch.vpit->pit_state.timer;
|
|
hrtimer_cancel(timer);
|
|
flush_kthread_work(&kvm->arch.vpit->expired);
|
|
kthread_stop(kvm->arch.vpit->worker_task);
|
|
kvm_free_irq_source_id(kvm, kvm->arch.vpit->irq_source_id);
|
|
mutex_unlock(&kvm->arch.vpit->pit_state.lock);
|
|
kfree(kvm->arch.vpit);
|
|
}
|
|
}
|