/*
* Copyright (c) 2009, Microsoft Corporation.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program; if not, write to the Free Software Foundation, Inc., 59 Temple
* Place - Suite 330, Boston, MA 02111-1307 USA.
*
* Authors:
* Haiyang Zhang <haiyangz@microsoft.com>
* Hank Janssen <hjanssen@microsoft.com>
*
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/hyperv.h>
#include <linux/version.h>
#include <linux/interrupt.h>
#include <linux/clockchips.h>
#include <asm/hyperv.h>
#include <asm/mshyperv.h>
#include "hyperv_vmbus.h"
/* The one and only */
struct hv_context hv_context = {
.synic_initialized = false,
.hypercall_page = NULL,
};
#define HV_TIMER_FREQUENCY (10 * 1000 * 1000) /* 100ns period */
#define HV_MAX_MAX_DELTA_TICKS 0xffffffff
#define HV_MIN_DELTA_TICKS 1
/*
* query_hypervisor_info - Get version info of the windows hypervisor
*/
unsigned int host_info_eax;
unsigned int host_info_ebx;
unsigned int host_info_ecx;
unsigned int host_info_edx;
static int query_hypervisor_info(void)
{
unsigned int eax;
unsigned int ebx;
unsigned int ecx;
unsigned int edx;
unsigned int max_leaf;
unsigned int op;
/*
* Its assumed that this is called after confirming that Viridian
* is present. Query id and revision.
*/
eax = 0;
ebx = 0;
ecx = 0;
edx = 0;
op = HVCPUID_VENDOR_MAXFUNCTION;
cpuid(op, &eax, &ebx, &ecx, &edx);
max_leaf = eax;
if (max_leaf >= HVCPUID_VERSION) {
eax = 0;
ebx = 0;
ecx = 0;
edx = 0;
op = HVCPUID_VERSION;
cpuid(op, &eax, &ebx, &ecx, &edx);
host_info_eax = eax;
host_info_ebx = ebx;
host_info_ecx = ecx;
host_info_edx = edx;
}
return max_leaf;
}
/*
* do_hypercall- Invoke the specified hypercall
*/
static u64 do_hypercall(u64 control, void *input, void *output)
{
#ifdef CONFIG_X86_64
u64 hv_status = 0;
u64 input_address = (input) ? virt_to_phys(input) : 0;
u64 output_address = (output) ? virt_to_phys(output) : 0;
void *hypercall_page = hv_context.hypercall_page;
__asm__ __volatile__("mov %0, %%r8" : : "r" (output_address) : "r8");
__asm__ __volatile__("call *%3" : "=a" (hv_status) :
"c" (control), "d" (input_address),
"m" (hypercall_page));
return hv_status;
#else
u32 control_hi = control >> 32;
u32 control_lo = control & 0xFFFFFFFF;
u32 hv_status_hi = 1;
u32 hv_status_lo = 1;
u64 input_address = (input) ? virt_to_phys(input) : 0;
u32 input_address_hi = input_address >> 32;
u32 input_address_lo = input_address & 0xFFFFFFFF;
u64 output_address = (output) ? virt_to_phys(output) : 0;
u32 output_address_hi = output_address >> 32;
u32 output_address_lo = output_address & 0xFFFFFFFF;
void *hypercall_page = hv_context.hypercall_page;
__asm__ __volatile__ ("call *%8" : "=d"(hv_status_hi),
"=a"(hv_status_lo) : "d" (control_hi),
"a" (control_lo), "b" (input_address_hi),
"c" (input_address_lo), "D"(output_address_hi),
"S"(output_address_lo), "m" (hypercall_page));
return hv_status_lo | ((u64)hv_status_hi << 32);
#endif /* !x86_64 */
}
/*
* hv_init - Main initialization routine.
*
* This routine must be called before any other routines in here are called
*/
int hv_init(void)
{
int max_leaf;
union hv_x64_msr_hypercall_contents hypercall_msr;
void *virtaddr = NULL;
memset(hv_context.synic_event_page, 0, sizeof(void *) * NR_CPUS);
memset(hv_context.synic_message_page, 0,
sizeof(void *) * NR_CPUS);
memset(hv_context.post_msg_page, 0,
sizeof(void *) * NR_CPUS);
memset(hv_context.vp_index, 0,
sizeof(int) * NR_CPUS);
memset(hv_context.event_dpc, 0,
sizeof(void *) * NR_CPUS);
memset(hv_context.clk_evt, 0,
sizeof(void *) * NR_CPUS);
max_leaf = query_hypervisor_info();
/*
* Write our OS ID.
*/
hv_context.guestid = generate_guest_id(0, LINUX_VERSION_CODE, 0);
wrmsrl(HV_X64_MSR_GUEST_OS_ID, hv_context.guestid);
/* See if the hypercall page is already set */
rdmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
virtaddr = __vmalloc(PAGE_SIZE, GFP_KERNEL, PAGE_KERNEL_EXEC);
if (!virtaddr)
goto cleanup;
hypercall_msr.enable = 1;
hypercall_msr.guest_physical_address = vmalloc_to_pfn(virtaddr);
wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
/* Confirm that hypercall page did get setup. */
hypercall_msr.as_uint64 = 0;
rdmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
if (!hypercall_msr.enable)
goto cleanup;
hv_context.hypercall_page = virtaddr;
return 0;
cleanup:
if (virtaddr) {
if (hypercall_msr.enable) {
hypercall_msr.as_uint64 = 0;
wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
}
vfree(virtaddr);
}
return -ENOTSUPP;
}
/*
* hv_cleanup - Cleanup routine.
*
* This routine is called normally during driver unloading or exiting.
*/
void hv_cleanup(void)
{
union hv_x64_msr_hypercall_contents hypercall_msr;
/* Reset our OS id */
wrmsrl(HV_X64_MSR_GUEST_OS_ID, 0);
if (hv_context.hypercall_page) {
hypercall_msr.as_uint64 = 0;
wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
vfree(hv_context.hypercall_page);
hv_context.hypercall_page = NULL;
}
}
/*
* hv_post_message - Post a message using the hypervisor message IPC.
*
* This involves a hypercall.
*/
int hv_post_message(union hv_connection_id connection_id,
enum hv_message_type message_type,
void *payload, size_t payload_size)
{
struct hv_input_post_message *aligned_msg;
u16 status;
if (payload_size > HV_MESSAGE_PAYLOAD_BYTE_COUNT)
return -EMSGSIZE;
aligned_msg = (struct hv_input_post_message *)
hv_context.post_msg_page[get_cpu()];
aligned_msg->connectionid = connection_id;
aligned_msg->reserved = 0;
aligned_msg->message_type = message_type;
aligned_msg->payload_size = payload_size;
memcpy((void *)aligned_msg->payload, payload, payload_size);
status = do_hypercall(HVCALL_POST_MESSAGE, aligned_msg, NULL)
& 0xFFFF;
put_cpu();
return status;
}
/*
* hv_signal_event -
* Signal an event on the specified connection using the hypervisor event IPC.
*
* This involves a hypercall.
*/
u16 hv_signal_event(void *con_id)
{
u16 status;
status = (do_hypercall(HVCALL_SIGNAL_EVENT, con_id, NULL) & 0xFFFF);
return status;
}
static int hv_ce_set_next_event(unsigned long delta,
struct clock_event_device *evt)
{
cycle_t current_tick;
WARN_ON(evt->mode != CLOCK_EVT_MODE_ONESHOT);
rdmsrl(HV_X64_MSR_TIME_REF_COUNT, current_tick);
current_tick += delta;
wrmsrl(HV_X64_MSR_STIMER0_COUNT, current_tick);
return 0;
}
static void hv_ce_setmode(enum clock_event_mode mode,
struct clock_event_device *evt)
{
union hv_timer_config timer_cfg;
switch (mode) {
case CLOCK_EVT_MODE_PERIODIC:
/* unsupported */
break;
case CLOCK_EVT_MODE_ONESHOT:
timer_cfg.enable = 1;
timer_cfg.auto_enable = 1;
timer_cfg.sintx = VMBUS_MESSAGE_SINT;
wrmsrl(HV_X64_MSR_STIMER0_CONFIG, timer_cfg.as_uint64);
break;
case CLOCK_EVT_MODE_UNUSED:
case CLOCK_EVT_MODE_SHUTDOWN:
wrmsrl(HV_X64_MSR_STIMER0_COUNT, 0);
wrmsrl(HV_X64_MSR_STIMER0_CONFIG, 0);
break;
case CLOCK_EVT_MODE_RESUME:
break;
}
}
static void hv_init_clockevent_device(struct clock_event_device *dev, int cpu)
{
dev->name = "Hyper-V clockevent";
dev->features = CLOCK_EVT_FEAT_ONESHOT;
dev->cpumask = cpumask_of(cpu);
dev->rating = 1000;
/*
* Avoid settint dev->owner = THIS_MODULE deliberately as doing so will
* result in clockevents_config_and_register() taking additional
* references to the hv_vmbus module making it impossible to unload.
*/
dev->set_mode = hv_ce_setmode;
dev->set_next_event = hv_ce_set_next_event;
}
int hv_synic_alloc(void)
{
size_t size = sizeof(struct tasklet_struct);
size_t ced_size = sizeof(struct clock_event_device);
int cpu;
for_each_online_cpu(cpu) {
hv_context.event_dpc[cpu] = kmalloc(size, GFP_ATOMIC);
if (hv_context.event_dpc[cpu] == NULL) {
pr_err("Unable to allocate event dpc\n");
goto err;
}
tasklet_init(hv_context.event_dpc[cpu], vmbus_on_event, cpu);
hv_context.clk_evt[cpu] = kzalloc(ced_size, GFP_ATOMIC);
if (hv_context.clk_evt[cpu] == NULL) {
pr_err("Unable to allocate clock event device\n");
goto err;
}
hv_init_clockevent_device(hv_context.clk_evt[cpu], cpu);
hv_context.synic_message_page[cpu] =
(void *)get_zeroed_page(GFP_ATOMIC);
if (hv_context.synic_message_page[cpu] == NULL) {
pr_err("Unable to allocate SYNIC message page\n");
goto err;
}
hv_context.synic_event_page[cpu] =
(void *)get_zeroed_page(GFP_ATOMIC);
if (hv_context.synic_event_page[cpu] == NULL) {
pr_err("Unable to allocate SYNIC event page\n");
goto err;
}
hv_context.post_msg_page[cpu] =
(void *)get_zeroed_page(GFP_ATOMIC);
if (hv_context.post_msg_page[cpu] == NULL) {
pr_err("Unable to allocate post msg page\n");
goto err;
}
}
return 0;
err:
return -ENOMEM;
}
static void hv_synic_free_cpu(int cpu)
{
kfree(hv_context.event_dpc[cpu]);
kfree(hv_context.clk_evt[cpu]);
if (hv_context.synic_event_page[cpu])
free_page((unsigned long)hv_context.synic_event_page[cpu]);
if (hv_context.synic_message_page[cpu])
free_page((unsigned long)hv_context.synic_message_page[cpu]);
if (hv_context.post_msg_page[cpu])
free_page((unsigned long)hv_context.post_msg_page[cpu]);
}
void hv_synic_free(void)
{
int cpu;
for_each_online_cpu(cpu)
hv_synic_free_cpu(cpu);
}
/*
* hv_synic_init - Initialize the Synthethic Interrupt Controller.
*
* If it is already initialized by another entity (ie x2v shim), we need to
* retrieve the initialized message and event pages. Otherwise, we create and
* initialize the message and event pages.
*/
void hv_synic_init(void *arg)
{
u64 version;
union hv_synic_simp simp;
union hv_synic_siefp siefp;
union hv_synic_sint shared_sint;
union hv_synic_scontrol sctrl;
u64 vp_index;
int cpu = smp_processor_id();
if (!hv_context.hypercall_page)
return;
/* Check the version */
rdmsrl(HV_X64_MSR_SVERSION, version);
/* Setup the Synic's message page */
rdmsrl(HV_X64_MSR_SIMP, simp.as_uint64);
simp.simp_enabled = 1;
simp.base_simp_gpa = virt_to_phys(hv_context.synic_message_page[cpu])
>> PAGE_SHIFT;
wrmsrl(HV_X64_MSR_SIMP, simp.as_uint64);
/* Setup the Synic's event page */
rdmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64);
siefp.siefp_enabled = 1;
siefp.base_siefp_gpa = virt_to_phys(hv_context.synic_event_page[cpu])
>> PAGE_SHIFT;
wrmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64);
/* Setup the shared SINT. */
rdmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64);
shared_sint.as_uint64 = 0;
shared_sint.vector = HYPERVISOR_CALLBACK_VECTOR;
shared_sint.masked = false;
shared_sint.auto_eoi = true;
wrmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64);
/* Enable the global synic bit */
rdmsrl(HV_X64_MSR_SCONTROL, sctrl.as_uint64);
sctrl.enable = 1;
wrmsrl(HV_X64_MSR_SCONTROL, sctrl.as_uint64);
hv_context.synic_initialized = true;
/*
* Setup the mapping between Hyper-V's notion
* of cpuid and Linux' notion of cpuid.
* This array will be indexed using Linux cpuid.
*/
rdmsrl(HV_X64_MSR_VP_INDEX, vp_index);
hv_context.vp_index[cpu] = (u32)vp_index;
INIT_LIST_HEAD(&hv_context.percpu_list[cpu]);
/*
* Register the per-cpu clockevent source.
*/
if (ms_hyperv.features & HV_X64_MSR_SYNTIMER_AVAILABLE)
clockevents_config_and_register(hv_context.clk_evt[cpu],
HV_TIMER_FREQUENCY,
HV_MIN_DELTA_TICKS,
HV_MAX_MAX_DELTA_TICKS);
return;
}
/*
* hv_synic_clockevents_cleanup - Cleanup clockevent devices
*/
void hv_synic_clockevents_cleanup(void)
{
int cpu;
if (!(ms_hyperv.features & HV_X64_MSR_SYNTIMER_AVAILABLE))
return;
for_each_online_cpu(cpu)
clockevents_unbind_device(hv_context.clk_evt[cpu], cpu);
}
/*
* hv_synic_cleanup - Cleanup routine for hv_synic_init().
*/
void hv_synic_cleanup(void *arg)
{
union hv_synic_sint shared_sint;
union hv_synic_simp simp;
union hv_synic_siefp siefp;
union hv_synic_scontrol sctrl;
int cpu = smp_processor_id();
if (!hv_context.synic_initialized)
return;
/* Turn off clockevent device */
if (ms_hyperv.features & HV_X64_MSR_SYNTIMER_AVAILABLE)
hv_ce_setmode(CLOCK_EVT_MODE_SHUTDOWN,
hv_context.clk_evt[cpu]);
rdmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64);
shared_sint.masked = 1;
/* Need to correctly cleanup in the case of SMP!!! */
/* Disable the interrupt */
wrmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64);
rdmsrl(HV_X64_MSR_SIMP, simp.as_uint64);
simp.simp_enabled = 0;
simp.base_simp_gpa = 0;
wrmsrl(HV_X64_MSR_SIMP, simp.as_uint64);
rdmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64);
siefp.siefp_enabled = 0;
siefp.base_siefp_gpa = 0;
wrmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64);
/* Disable the global synic bit */
rdmsrl(HV_X64_MSR_SCONTROL, sctrl.as_uint64);
sctrl.enable = 0;
wrmsrl(HV_X64_MSR_SCONTROL, sctrl.as_uint64);
hv_synic_free_cpu(cpu);
}