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-rw-r--r--arch/x86/kernel/vmiclock_32.c317
1 files changed, 0 insertions, 317 deletions
diff --git a/arch/x86/kernel/vmiclock_32.c b/arch/x86/kernel/vmiclock_32.c
deleted file mode 100644
index 5e1ff66ecd73..000000000000
--- a/arch/x86/kernel/vmiclock_32.c
+++ /dev/null
@@ -1,317 +0,0 @@
1/*
2 * VMI paravirtual timer support routines.
3 *
4 * Copyright (C) 2007, VMware, Inc.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful, but
12 * WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
14 * NON INFRINGEMENT. See the GNU General Public License for more
15 * details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20 *
21 */
22
23#include <linux/smp.h>
24#include <linux/interrupt.h>
25#include <linux/cpumask.h>
26#include <linux/clocksource.h>
27#include <linux/clockchips.h>
28
29#include <asm/vmi.h>
30#include <asm/vmi_time.h>
31#include <asm/apicdef.h>
32#include <asm/apic.h>
33#include <asm/timer.h>
34#include <asm/i8253.h>
35#include <asm/irq_vectors.h>
36
37#define VMI_ONESHOT (VMI_ALARM_IS_ONESHOT | VMI_CYCLES_REAL | vmi_get_alarm_wiring())
38#define VMI_PERIODIC (VMI_ALARM_IS_PERIODIC | VMI_CYCLES_REAL | vmi_get_alarm_wiring())
39
40static DEFINE_PER_CPU(struct clock_event_device, local_events);
41
42static inline u32 vmi_counter(u32 flags)
43{
44 /* Given VMI_ONESHOT or VMI_PERIODIC, return the corresponding
45 * cycle counter. */
46 return flags & VMI_ALARM_COUNTER_MASK;
47}
48
49/* paravirt_ops.get_wallclock = vmi_get_wallclock */
50unsigned long vmi_get_wallclock(void)
51{
52 unsigned long long wallclock;
53 wallclock = vmi_timer_ops.get_wallclock(); // nsec
54 (void)do_div(wallclock, 1000000000); // sec
55
56 return wallclock;
57}
58
59/* paravirt_ops.set_wallclock = vmi_set_wallclock */
60int vmi_set_wallclock(unsigned long now)
61{
62 return 0;
63}
64
65/* paravirt_ops.sched_clock = vmi_sched_clock */
66unsigned long long vmi_sched_clock(void)
67{
68 return cycles_2_ns(vmi_timer_ops.get_cycle_counter(VMI_CYCLES_AVAILABLE));
69}
70
71/* x86_platform.calibrate_tsc = vmi_tsc_khz */
72unsigned long vmi_tsc_khz(void)
73{
74 unsigned long long khz;
75 khz = vmi_timer_ops.get_cycle_frequency();
76 (void)do_div(khz, 1000);
77 return khz;
78}
79
80static inline unsigned int vmi_get_timer_vector(void)
81{
82 return IRQ0_VECTOR;
83}
84
85/** vmi clockchip */
86#ifdef CONFIG_X86_LOCAL_APIC
87static unsigned int startup_timer_irq(unsigned int irq)
88{
89 unsigned long val = apic_read(APIC_LVTT);
90 apic_write(APIC_LVTT, vmi_get_timer_vector());
91
92 return (val & APIC_SEND_PENDING);
93}
94
95static void mask_timer_irq(unsigned int irq)
96{
97 unsigned long val = apic_read(APIC_LVTT);
98 apic_write(APIC_LVTT, val | APIC_LVT_MASKED);
99}
100
101static void unmask_timer_irq(unsigned int irq)
102{
103 unsigned long val = apic_read(APIC_LVTT);
104 apic_write(APIC_LVTT, val & ~APIC_LVT_MASKED);
105}
106
107static void ack_timer_irq(unsigned int irq)
108{
109 ack_APIC_irq();
110}
111
112static struct irq_chip vmi_chip __read_mostly = {
113 .name = "VMI-LOCAL",
114 .startup = startup_timer_irq,
115 .mask = mask_timer_irq,
116 .unmask = unmask_timer_irq,
117 .ack = ack_timer_irq
118};
119#endif
120
121/** vmi clockevent */
122#define VMI_ALARM_WIRED_IRQ0 0x00000000
123#define VMI_ALARM_WIRED_LVTT 0x00010000
124static int vmi_wiring = VMI_ALARM_WIRED_IRQ0;
125
126static inline int vmi_get_alarm_wiring(void)
127{
128 return vmi_wiring;
129}
130
131static void vmi_timer_set_mode(enum clock_event_mode mode,
132 struct clock_event_device *evt)
133{
134 cycle_t now, cycles_per_hz;
135 BUG_ON(!irqs_disabled());
136
137 switch (mode) {
138 case CLOCK_EVT_MODE_ONESHOT:
139 case CLOCK_EVT_MODE_RESUME:
140 break;
141 case CLOCK_EVT_MODE_PERIODIC:
142 cycles_per_hz = vmi_timer_ops.get_cycle_frequency();
143 (void)do_div(cycles_per_hz, HZ);
144 now = vmi_timer_ops.get_cycle_counter(vmi_counter(VMI_PERIODIC));
145 vmi_timer_ops.set_alarm(VMI_PERIODIC, now, cycles_per_hz);
146 break;
147 case CLOCK_EVT_MODE_UNUSED:
148 case CLOCK_EVT_MODE_SHUTDOWN:
149 switch (evt->mode) {
150 case CLOCK_EVT_MODE_ONESHOT:
151 vmi_timer_ops.cancel_alarm(VMI_ONESHOT);
152 break;
153 case CLOCK_EVT_MODE_PERIODIC:
154 vmi_timer_ops.cancel_alarm(VMI_PERIODIC);
155 break;
156 default:
157 break;
158 }
159 break;
160 default:
161 break;
162 }
163}
164
165static int vmi_timer_next_event(unsigned long delta,
166 struct clock_event_device *evt)
167{
168 /* Unfortunately, set_next_event interface only passes relative
169 * expiry, but we want absolute expiry. It'd be better if were
170 * were passed an absolute expiry, since a bunch of time may
171 * have been stolen between the time the delta is computed and
172 * when we set the alarm below. */
173 cycle_t now = vmi_timer_ops.get_cycle_counter(vmi_counter(VMI_ONESHOT));
174
175 BUG_ON(evt->mode != CLOCK_EVT_MODE_ONESHOT);
176 vmi_timer_ops.set_alarm(VMI_ONESHOT, now + delta, 0);
177 return 0;
178}
179
180static struct clock_event_device vmi_clockevent = {
181 .name = "vmi-timer",
182 .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
183 .shift = 22,
184 .set_mode = vmi_timer_set_mode,
185 .set_next_event = vmi_timer_next_event,
186 .rating = 1000,
187 .irq = 0,
188};
189
190static irqreturn_t vmi_timer_interrupt(int irq, void *dev_id)
191{
192 struct clock_event_device *evt = &__get_cpu_var(local_events);
193 evt->event_handler(evt);
194 return IRQ_HANDLED;
195}
196
197static struct irqaction vmi_clock_action = {
198 .name = "vmi-timer",
199 .handler = vmi_timer_interrupt,
200 .flags = IRQF_DISABLED | IRQF_NOBALANCING | IRQF_TIMER,
201};
202
203static void __devinit vmi_time_init_clockevent(void)
204{
205 cycle_t cycles_per_msec;
206 struct clock_event_device *evt;
207
208 int cpu = smp_processor_id();
209 evt = &__get_cpu_var(local_events);
210
211 /* Use cycles_per_msec since div_sc params are 32-bits. */
212 cycles_per_msec = vmi_timer_ops.get_cycle_frequency();
213 (void)do_div(cycles_per_msec, 1000);
214
215 memcpy(evt, &vmi_clockevent, sizeof(*evt));
216 /* Must pick .shift such that .mult fits in 32-bits. Choosing
217 * .shift to be 22 allows 2^(32-22) cycles per nano-seconds
218 * before overflow. */
219 evt->mult = div_sc(cycles_per_msec, NSEC_PER_MSEC, evt->shift);
220 /* Upper bound is clockevent's use of ulong for cycle deltas. */
221 evt->max_delta_ns = clockevent_delta2ns(ULONG_MAX, evt);
222 evt->min_delta_ns = clockevent_delta2ns(1, evt);
223 evt->cpumask = cpumask_of(cpu);
224
225 printk(KERN_WARNING "vmi: registering clock event %s. mult=%u shift=%u\n",
226 evt->name, evt->mult, evt->shift);
227 clockevents_register_device(evt);
228}
229
230void __init vmi_time_init(void)
231{
232 unsigned int cpu;
233 /* Disable PIT: BIOSes start PIT CH0 with 18.2hz peridic. */
234 outb_pit(0x3a, PIT_MODE); /* binary, mode 5, LSB/MSB, ch 0 */
235
236 vmi_time_init_clockevent();
237 setup_irq(0, &vmi_clock_action);
238 for_each_possible_cpu(cpu)
239 per_cpu(vector_irq, cpu)[vmi_get_timer_vector()] = 0;
240}
241
242#ifdef CONFIG_X86_LOCAL_APIC
243void __devinit vmi_time_bsp_init(void)
244{
245 /*
246 * On APIC systems, we want local timers to fire on each cpu. We do
247 * this by programming LVTT to deliver timer events to the IRQ handler
248 * for IRQ-0, since we can't re-use the APIC local timer handler
249 * without interfering with that code.
250 */
251 clockevents_notify(CLOCK_EVT_NOTIFY_SUSPEND, NULL);
252 local_irq_disable();
253#ifdef CONFIG_SMP
254 /*
255 * XXX handle_percpu_irq only defined for SMP; we need to switch over
256 * to using it, since this is a local interrupt, which each CPU must
257 * handle individually without locking out or dropping simultaneous
258 * local timers on other CPUs. We also don't want to trigger the
259 * quirk workaround code for interrupts which gets invoked from
260 * handle_percpu_irq via eoi, so we use our own IRQ chip.
261 */
262 set_irq_chip_and_handler_name(0, &vmi_chip, handle_percpu_irq, "lvtt");
263#else
264 set_irq_chip_and_handler_name(0, &vmi_chip, handle_edge_irq, "lvtt");
265#endif
266 vmi_wiring = VMI_ALARM_WIRED_LVTT;
267 apic_write(APIC_LVTT, vmi_get_timer_vector());
268 local_irq_enable();
269 clockevents_notify(CLOCK_EVT_NOTIFY_RESUME, NULL);
270}
271
272void __devinit vmi_time_ap_init(void)
273{
274 vmi_time_init_clockevent();
275 apic_write(APIC_LVTT, vmi_get_timer_vector());
276}
277#endif
278
279/** vmi clocksource */
280static struct clocksource clocksource_vmi;
281
282static cycle_t read_real_cycles(struct clocksource *cs)
283{
284 cycle_t ret = (cycle_t)vmi_timer_ops.get_cycle_counter(VMI_CYCLES_REAL);
285 return max(ret, clocksource_vmi.cycle_last);
286}
287
288static struct clocksource clocksource_vmi = {
289 .name = "vmi-timer",
290 .rating = 450,
291 .read = read_real_cycles,
292 .mask = CLOCKSOURCE_MASK(64),
293 .mult = 0, /* to be set */
294 .shift = 22,
295 .flags = CLOCK_SOURCE_IS_CONTINUOUS,
296};
297
298static int __init init_vmi_clocksource(void)
299{
300 cycle_t cycles_per_msec;
301
302 if (!vmi_timer_ops.get_cycle_frequency)
303 return 0;
304 /* Use khz2mult rather than hz2mult since hz arg is only 32-bits. */
305 cycles_per_msec = vmi_timer_ops.get_cycle_frequency();
306 (void)do_div(cycles_per_msec, 1000);
307
308 /* Note that clocksource.{mult, shift} converts in the opposite direction
309 * as clockevents. */
310 clocksource_vmi.mult = clocksource_khz2mult(cycles_per_msec,
311 clocksource_vmi.shift);
312
313 printk(KERN_WARNING "vmi: registering clock source khz=%lld\n", cycles_per_msec);
314 return clocksource_register(&clocksource_vmi);
315
316}
317module_init(init_vmi_clocksource);
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