qemu/include/hw/s390x/tod.h
David Hildenbrand 7de3b1cdc6 s390x/tcg: properly implement the TOD
Right now, each CPU has its own TOD. Especially, the TOD will differ
based on creation time of a CPU - e.g. when hotplugging a CPU the times
will differ quite a lot, resulting in stall warnings in the guest.

Let's use a single TOD by implementing our new TOD device. Prepare it
for TOD-clock epoch extension.

Most importantly, whenever we set the TOD, we have to update the CKC
timer.

Introduce "tcg_s390x.h" just like "kvm_s390x.h" for tcg specific
function declarations that should not go into cpu.h.

Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20180627134410.4901-6-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2018-07-02 10:37:38 +02:00

66 lines
1.7 KiB
C

/*
* TOD (Time Of Day) clock
*
* Copyright 2018 Red Hat, Inc.
* Author(s): David Hildenbrand <david@redhat.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*/
#ifndef HW_S390_TOD_H
#define HW_S390_TOD_H
#include "hw/qdev.h"
typedef struct S390TOD {
uint8_t high;
uint64_t low;
} S390TOD;
#define TYPE_S390_TOD "s390-tod"
#define S390_TOD(obj) OBJECT_CHECK(S390TODState, (obj), TYPE_S390_TOD)
#define S390_TOD_CLASS(oc) OBJECT_CLASS_CHECK(S390TODClass, (oc), \
TYPE_S390_TOD)
#define S390_TOD_GET_CLASS(obj) OBJECT_GET_CLASS(S390TODClass, (obj), \
TYPE_S390_TOD)
#define TYPE_KVM_S390_TOD TYPE_S390_TOD "-kvm"
#define TYPE_QEMU_S390_TOD TYPE_S390_TOD "-qemu"
typedef struct S390TODState {
/* private */
DeviceState parent_obj;
/* unused by KVM implementation */
S390TOD base;
} S390TODState;
typedef struct S390TODClass {
/* private */
DeviceClass parent_class;
/* public */
void (*get)(const S390TODState *td, S390TOD *tod, Error **errp);
void (*set)(S390TODState *td, const S390TOD *tod, Error **errp);
} S390TODClass;
/* The value of the TOD clock for 1.1.1970. */
#define TOD_UNIX_EPOCH 0x7d91048bca000000ULL
/* Converts ns to s390's clock format */
static inline uint64_t time2tod(uint64_t ns)
{
return (ns << 9) / 125 + (((ns & 0xff10000000000000ull) / 125) << 9);
}
/* Converts s390's clock format to ns */
static inline uint64_t tod2time(uint64_t t)
{
return ((t >> 9) * 125) + (((t & 0x1ff) * 125) >> 9);
}
void s390_init_tod(void);
S390TODState *s390_get_todstate(void);
#endif