2 * Copyright (c) 2009, Microsoft Corporation.
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms and conditions of the GNU General Public License,
6 * version 2, as published by the Free Software Foundation.
8 * This program is distributed in the hope it will be useful, but WITHOUT
9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
13 * You should have received a copy of the GNU General Public License along with
14 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
15 * Place - Suite 330, Boston, MA 02111-1307 USA.
18 * Haiyang Zhang <haiyangz@microsoft.com>
19 * Hank Janssen <hjanssen@microsoft.com>
22 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
24 #include <linux/kernel.h>
26 #include <linux/slab.h>
27 #include <linux/vmalloc.h>
28 #include <linux/hyperv.h>
29 #include <linux/version.h>
30 #include <linux/interrupt.h>
31 #include <linux/clockchips.h>
32 #include <asm/hyperv.h>
33 #include <asm/mshyperv.h>
34 #include "hyperv_vmbus.h"
36 /* The one and only */
37 struct hv_context hv_context
= {
38 .synic_initialized
= false,
39 .hypercall_page
= NULL
,
42 #define HV_TIMER_FREQUENCY (10 * 1000 * 1000) /* 100ns period */
43 #define HV_MAX_MAX_DELTA_TICKS 0xffffffff
44 #define HV_MIN_DELTA_TICKS 1
47 * query_hypervisor_info - Get version info of the windows hypervisor
49 unsigned int host_info_eax
;
50 unsigned int host_info_ebx
;
51 unsigned int host_info_ecx
;
52 unsigned int host_info_edx
;
54 static int query_hypervisor_info(void)
60 unsigned int max_leaf
;
64 * Its assumed that this is called after confirming that Viridian
65 * is present. Query id and revision.
71 op
= HVCPUID_VENDOR_MAXFUNCTION
;
72 cpuid(op
, &eax
, &ebx
, &ecx
, &edx
);
76 if (max_leaf
>= HVCPUID_VERSION
) {
82 cpuid(op
, &eax
, &ebx
, &ecx
, &edx
);
92 * hv_do_hypercall- Invoke the specified hypercall
94 u64
hv_do_hypercall(u64 control
, void *input
, void *output
)
96 u64 input_address
= (input
) ? virt_to_phys(input
) : 0;
97 u64 output_address
= (output
) ? virt_to_phys(output
) : 0;
98 void *hypercall_page
= hv_context
.hypercall_page
;
103 return (u64
)ULLONG_MAX
;
105 __asm__
__volatile__("mov %0, %%r8" : : "r" (output_address
) : "r8");
106 __asm__
__volatile__("call *%3" : "=a" (hv_status
) :
107 "c" (control
), "d" (input_address
),
108 "m" (hypercall_page
));
114 u32 control_hi
= control
>> 32;
115 u32 control_lo
= control
& 0xFFFFFFFF;
116 u32 hv_status_hi
= 1;
117 u32 hv_status_lo
= 1;
118 u32 input_address_hi
= input_address
>> 32;
119 u32 input_address_lo
= input_address
& 0xFFFFFFFF;
120 u32 output_address_hi
= output_address
>> 32;
121 u32 output_address_lo
= output_address
& 0xFFFFFFFF;
124 return (u64
)ULLONG_MAX
;
126 __asm__
__volatile__ ("call *%8" : "=d"(hv_status_hi
),
127 "=a"(hv_status_lo
) : "d" (control_hi
),
128 "a" (control_lo
), "b" (input_address_hi
),
129 "c" (input_address_lo
), "D"(output_address_hi
),
130 "S"(output_address_lo
), "m" (hypercall_page
));
132 return hv_status_lo
| ((u64
)hv_status_hi
<< 32);
135 EXPORT_SYMBOL_GPL(hv_do_hypercall
);
138 static u64
read_hv_clock_tsc(struct clocksource
*arg
)
141 struct ms_hyperv_tsc_page
*tsc_pg
= hv_context
.tsc_page
;
143 if (tsc_pg
->tsc_sequence
!= 0) {
145 * Use the tsc page to compute the value.
150 u32 sequence
= tsc_pg
->tsc_sequence
;
152 u64 scale
= tsc_pg
->tsc_scale
;
153 s64 offset
= tsc_pg
->tsc_offset
;
156 /* current_tick = ((cur_tsc *scale) >> 64) + offset */
158 : "=d" (current_tick
), "=a" (tmp
)
159 : "a" (cur_tsc
), "r" (scale
));
161 current_tick
+= offset
;
162 if (tsc_pg
->tsc_sequence
== sequence
)
165 if (tsc_pg
->tsc_sequence
!= 0)
168 * Fallback using MSR method.
173 rdmsrl(HV_X64_MSR_TIME_REF_COUNT
, current_tick
);
177 static struct clocksource hyperv_cs_tsc
= {
178 .name
= "hyperv_clocksource_tsc_page",
180 .read
= read_hv_clock_tsc
,
181 .mask
= CLOCKSOURCE_MASK(64),
182 .flags
= CLOCK_SOURCE_IS_CONTINUOUS
,
188 * hv_init - Main initialization routine.
190 * This routine must be called before any other routines in here are called
195 union hv_x64_msr_hypercall_contents hypercall_msr
;
197 memset(hv_context
.synic_event_page
, 0, sizeof(void *) * NR_CPUS
);
198 memset(hv_context
.synic_message_page
, 0,
199 sizeof(void *) * NR_CPUS
);
200 memset(hv_context
.post_msg_page
, 0,
201 sizeof(void *) * NR_CPUS
);
202 memset(hv_context
.vp_index
, 0,
203 sizeof(int) * NR_CPUS
);
204 memset(hv_context
.event_dpc
, 0,
205 sizeof(void *) * NR_CPUS
);
206 memset(hv_context
.msg_dpc
, 0,
207 sizeof(void *) * NR_CPUS
);
208 memset(hv_context
.clk_evt
, 0,
209 sizeof(void *) * NR_CPUS
);
211 max_leaf
= query_hypervisor_info();
214 /* See if the hypercall page is already set */
215 hypercall_msr
.as_uint64
= 0;
216 rdmsrl(HV_X64_MSR_HYPERCALL
, hypercall_msr
.as_uint64
);
218 if (!hypercall_msr
.enable
)
221 hv_context
.hypercall_page
= hv_hypercall_pg
;
224 if (ms_hyperv
.features
& HV_X64_MSR_REFERENCE_TSC_AVAILABLE
) {
225 union hv_x64_msr_hypercall_contents tsc_msr
;
228 va_tsc
= __vmalloc(PAGE_SIZE
, GFP_KERNEL
, PAGE_KERNEL
);
231 hv_context
.tsc_page
= va_tsc
;
233 rdmsrl(HV_X64_MSR_REFERENCE_TSC
, tsc_msr
.as_uint64
);
236 tsc_msr
.guest_physical_address
= vmalloc_to_pfn(va_tsc
);
238 wrmsrl(HV_X64_MSR_REFERENCE_TSC
, tsc_msr
.as_uint64
);
239 clocksource_register_hz(&hyperv_cs_tsc
, NSEC_PER_SEC
/100);
249 * hv_cleanup - Cleanup routine.
251 * This routine is called normally during driver unloading or exiting.
253 void hv_cleanup(bool crash
)
257 union hv_x64_msr_hypercall_contents hypercall_msr
;
259 * Cleanup the TSC page based CS.
261 if (ms_hyperv
.features
& HV_X64_MSR_REFERENCE_TSC_AVAILABLE
) {
263 * Crash can happen in an interrupt context and unregistering
264 * a clocksource is impossible and redundant in this case.
266 if (!oops_in_progress
) {
267 clocksource_change_rating(&hyperv_cs_tsc
, 10);
268 clocksource_unregister(&hyperv_cs_tsc
);
271 hypercall_msr
.as_uint64
= 0;
272 wrmsrl(HV_X64_MSR_REFERENCE_TSC
, hypercall_msr
.as_uint64
);
274 vfree(hv_context
.tsc_page
);
275 hv_context
.tsc_page
= NULL
;
282 * hv_post_message - Post a message using the hypervisor message IPC.
284 * This involves a hypercall.
286 int hv_post_message(union hv_connection_id connection_id
,
287 enum hv_message_type message_type
,
288 void *payload
, size_t payload_size
)
291 struct hv_input_post_message
*aligned_msg
;
294 if (payload_size
> HV_MESSAGE_PAYLOAD_BYTE_COUNT
)
297 aligned_msg
= (struct hv_input_post_message
*)
298 hv_context
.post_msg_page
[get_cpu()];
300 aligned_msg
->connectionid
= connection_id
;
301 aligned_msg
->reserved
= 0;
302 aligned_msg
->message_type
= message_type
;
303 aligned_msg
->payload_size
= payload_size
;
304 memcpy((void *)aligned_msg
->payload
, payload
, payload_size
);
306 status
= hv_do_hypercall(HVCALL_POST_MESSAGE
, aligned_msg
, NULL
);
309 return status
& 0xFFFF;
312 static int hv_ce_set_next_event(unsigned long delta
,
313 struct clock_event_device
*evt
)
317 WARN_ON(!clockevent_state_oneshot(evt
));
319 rdmsrl(HV_X64_MSR_TIME_REF_COUNT
, current_tick
);
320 current_tick
+= delta
;
321 wrmsrl(HV_X64_MSR_STIMER0_COUNT
, current_tick
);
325 static int hv_ce_shutdown(struct clock_event_device
*evt
)
327 wrmsrl(HV_X64_MSR_STIMER0_COUNT
, 0);
328 wrmsrl(HV_X64_MSR_STIMER0_CONFIG
, 0);
333 static int hv_ce_set_oneshot(struct clock_event_device
*evt
)
335 union hv_timer_config timer_cfg
;
337 timer_cfg
.enable
= 1;
338 timer_cfg
.auto_enable
= 1;
339 timer_cfg
.sintx
= VMBUS_MESSAGE_SINT
;
340 wrmsrl(HV_X64_MSR_STIMER0_CONFIG
, timer_cfg
.as_uint64
);
345 static void hv_init_clockevent_device(struct clock_event_device
*dev
, int cpu
)
347 dev
->name
= "Hyper-V clockevent";
348 dev
->features
= CLOCK_EVT_FEAT_ONESHOT
;
349 dev
->cpumask
= cpumask_of(cpu
);
352 * Avoid settint dev->owner = THIS_MODULE deliberately as doing so will
353 * result in clockevents_config_and_register() taking additional
354 * references to the hv_vmbus module making it impossible to unload.
357 dev
->set_state_shutdown
= hv_ce_shutdown
;
358 dev
->set_state_oneshot
= hv_ce_set_oneshot
;
359 dev
->set_next_event
= hv_ce_set_next_event
;
363 int hv_synic_alloc(void)
365 size_t size
= sizeof(struct tasklet_struct
);
366 size_t ced_size
= sizeof(struct clock_event_device
);
369 hv_context
.hv_numa_map
= kzalloc(sizeof(struct cpumask
) * nr_node_ids
,
371 if (hv_context
.hv_numa_map
== NULL
) {
372 pr_err("Unable to allocate NUMA map\n");
376 for_each_present_cpu(cpu
) {
377 hv_context
.event_dpc
[cpu
] = kmalloc(size
, GFP_ATOMIC
);
378 if (hv_context
.event_dpc
[cpu
] == NULL
) {
379 pr_err("Unable to allocate event dpc\n");
382 tasklet_init(hv_context
.event_dpc
[cpu
], vmbus_on_event
, cpu
);
384 hv_context
.msg_dpc
[cpu
] = kmalloc(size
, GFP_ATOMIC
);
385 if (hv_context
.msg_dpc
[cpu
] == NULL
) {
386 pr_err("Unable to allocate event dpc\n");
389 tasklet_init(hv_context
.msg_dpc
[cpu
], vmbus_on_msg_dpc
, cpu
);
391 hv_context
.clk_evt
[cpu
] = kzalloc(ced_size
, GFP_ATOMIC
);
392 if (hv_context
.clk_evt
[cpu
] == NULL
) {
393 pr_err("Unable to allocate clock event device\n");
397 hv_init_clockevent_device(hv_context
.clk_evt
[cpu
], cpu
);
399 hv_context
.synic_message_page
[cpu
] =
400 (void *)get_zeroed_page(GFP_ATOMIC
);
402 if (hv_context
.synic_message_page
[cpu
] == NULL
) {
403 pr_err("Unable to allocate SYNIC message page\n");
407 hv_context
.synic_event_page
[cpu
] =
408 (void *)get_zeroed_page(GFP_ATOMIC
);
410 if (hv_context
.synic_event_page
[cpu
] == NULL
) {
411 pr_err("Unable to allocate SYNIC event page\n");
415 hv_context
.post_msg_page
[cpu
] =
416 (void *)get_zeroed_page(GFP_ATOMIC
);
418 if (hv_context
.post_msg_page
[cpu
] == NULL
) {
419 pr_err("Unable to allocate post msg page\n");
423 INIT_LIST_HEAD(&hv_context
.percpu_list
[cpu
]);
431 static void hv_synic_free_cpu(int cpu
)
433 kfree(hv_context
.event_dpc
[cpu
]);
434 kfree(hv_context
.msg_dpc
[cpu
]);
435 kfree(hv_context
.clk_evt
[cpu
]);
436 if (hv_context
.synic_event_page
[cpu
])
437 free_page((unsigned long)hv_context
.synic_event_page
[cpu
]);
438 if (hv_context
.synic_message_page
[cpu
])
439 free_page((unsigned long)hv_context
.synic_message_page
[cpu
]);
440 if (hv_context
.post_msg_page
[cpu
])
441 free_page((unsigned long)hv_context
.post_msg_page
[cpu
]);
444 void hv_synic_free(void)
448 kfree(hv_context
.hv_numa_map
);
449 for_each_present_cpu(cpu
)
450 hv_synic_free_cpu(cpu
);
454 * hv_synic_init - Initialize the Synthethic Interrupt Controller.
456 * If it is already initialized by another entity (ie x2v shim), we need to
457 * retrieve the initialized message and event pages. Otherwise, we create and
458 * initialize the message and event pages.
460 int hv_synic_init(unsigned int cpu
)
463 union hv_synic_simp simp
;
464 union hv_synic_siefp siefp
;
465 union hv_synic_sint shared_sint
;
466 union hv_synic_scontrol sctrl
;
469 if (!hv_context
.hypercall_page
)
472 /* Check the version */
473 rdmsrl(HV_X64_MSR_SVERSION
, version
);
475 /* Setup the Synic's message page */
476 rdmsrl(HV_X64_MSR_SIMP
, simp
.as_uint64
);
477 simp
.simp_enabled
= 1;
478 simp
.base_simp_gpa
= virt_to_phys(hv_context
.synic_message_page
[cpu
])
481 wrmsrl(HV_X64_MSR_SIMP
, simp
.as_uint64
);
483 /* Setup the Synic's event page */
484 rdmsrl(HV_X64_MSR_SIEFP
, siefp
.as_uint64
);
485 siefp
.siefp_enabled
= 1;
486 siefp
.base_siefp_gpa
= virt_to_phys(hv_context
.synic_event_page
[cpu
])
489 wrmsrl(HV_X64_MSR_SIEFP
, siefp
.as_uint64
);
491 /* Setup the shared SINT. */
492 rdmsrl(HV_X64_MSR_SINT0
+ VMBUS_MESSAGE_SINT
, shared_sint
.as_uint64
);
494 shared_sint
.as_uint64
= 0;
495 shared_sint
.vector
= HYPERVISOR_CALLBACK_VECTOR
;
496 shared_sint
.masked
= false;
497 shared_sint
.auto_eoi
= true;
499 wrmsrl(HV_X64_MSR_SINT0
+ VMBUS_MESSAGE_SINT
, shared_sint
.as_uint64
);
501 /* Enable the global synic bit */
502 rdmsrl(HV_X64_MSR_SCONTROL
, sctrl
.as_uint64
);
505 wrmsrl(HV_X64_MSR_SCONTROL
, sctrl
.as_uint64
);
507 hv_context
.synic_initialized
= true;
510 * Setup the mapping between Hyper-V's notion
511 * of cpuid and Linux' notion of cpuid.
512 * This array will be indexed using Linux cpuid.
514 rdmsrl(HV_X64_MSR_VP_INDEX
, vp_index
);
515 hv_context
.vp_index
[cpu
] = (u32
)vp_index
;
518 * Register the per-cpu clockevent source.
520 if (ms_hyperv
.features
& HV_X64_MSR_SYNTIMER_AVAILABLE
)
521 clockevents_config_and_register(hv_context
.clk_evt
[cpu
],
524 HV_MAX_MAX_DELTA_TICKS
);
529 * hv_synic_clockevents_cleanup - Cleanup clockevent devices
531 void hv_synic_clockevents_cleanup(void)
535 if (!(ms_hyperv
.features
& HV_X64_MSR_SYNTIMER_AVAILABLE
))
538 for_each_present_cpu(cpu
)
539 clockevents_unbind_device(hv_context
.clk_evt
[cpu
], cpu
);
543 * hv_synic_cleanup - Cleanup routine for hv_synic_init().
545 int hv_synic_cleanup(unsigned int cpu
)
547 union hv_synic_sint shared_sint
;
548 union hv_synic_simp simp
;
549 union hv_synic_siefp siefp
;
550 union hv_synic_scontrol sctrl
;
551 struct vmbus_channel
*channel
, *sc
;
552 bool channel_found
= false;
555 if (!hv_context
.synic_initialized
)
559 * Search for channels which are bound to the CPU we're about to
560 * cleanup. In case we find one and vmbus is still connected we need to
561 * fail, this will effectively prevent CPU offlining. There is no way
562 * we can re-bind channels to different CPUs for now.
564 mutex_lock(&vmbus_connection
.channel_mutex
);
565 list_for_each_entry(channel
, &vmbus_connection
.chn_list
, listentry
) {
566 if (channel
->target_cpu
== cpu
) {
567 channel_found
= true;
570 spin_lock_irqsave(&channel
->lock
, flags
);
571 list_for_each_entry(sc
, &channel
->sc_list
, sc_list
) {
572 if (sc
->target_cpu
== cpu
) {
573 channel_found
= true;
577 spin_unlock_irqrestore(&channel
->lock
, flags
);
581 mutex_unlock(&vmbus_connection
.channel_mutex
);
583 if (channel_found
&& vmbus_connection
.conn_state
== CONNECTED
)
586 /* Turn off clockevent device */
587 if (ms_hyperv
.features
& HV_X64_MSR_SYNTIMER_AVAILABLE
) {
588 clockevents_unbind_device(hv_context
.clk_evt
[cpu
], cpu
);
589 hv_ce_shutdown(hv_context
.clk_evt
[cpu
]);
592 rdmsrl(HV_X64_MSR_SINT0
+ VMBUS_MESSAGE_SINT
, shared_sint
.as_uint64
);
594 shared_sint
.masked
= 1;
596 /* Need to correctly cleanup in the case of SMP!!! */
597 /* Disable the interrupt */
598 wrmsrl(HV_X64_MSR_SINT0
+ VMBUS_MESSAGE_SINT
, shared_sint
.as_uint64
);
600 rdmsrl(HV_X64_MSR_SIMP
, simp
.as_uint64
);
601 simp
.simp_enabled
= 0;
602 simp
.base_simp_gpa
= 0;
604 wrmsrl(HV_X64_MSR_SIMP
, simp
.as_uint64
);
606 rdmsrl(HV_X64_MSR_SIEFP
, siefp
.as_uint64
);
607 siefp
.siefp_enabled
= 0;
608 siefp
.base_siefp_gpa
= 0;
610 wrmsrl(HV_X64_MSR_SIEFP
, siefp
.as_uint64
);
612 /* Disable the global synic bit */
613 rdmsrl(HV_X64_MSR_SCONTROL
, sctrl
.as_uint64
);
615 wrmsrl(HV_X64_MSR_SCONTROL
, sctrl
.as_uint64
);