qemu/hw/misc/armsse-mhu.c
Peter Maydell cdf63440ea hw/misc/armsse-mhu.c: Model the SSE-200 Message Handling Unit
Implement a model of the Message Handling Unit (MHU) found in
the Arm SSE-200. This is a simple device which just contains
some registers which allow the two cores of the SSE-200
to raise interrupts on each other.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20190219125808.25174-2-peter.maydell@linaro.org
2019-02-28 11:03:04 +00:00

199 lines
4.9 KiB
C

/*
* ARM SSE-200 Message Handling Unit (MHU)
*
* Copyright (c) 2019 Linaro Limited
* Written by Peter Maydell
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 or
* (at your option) any later version.
*/
/*
* This is a model of the Message Handling Unit (MHU) which is part of the
* Arm SSE-200 and documented in
* http://infocenter.arm.com/help/topic/com.arm.doc.101104_0100_00_en/corelink_sse200_subsystem_for_embedded_technical_reference_manual_101104_0100_00_en.pdf
*/
#include "qemu/osdep.h"
#include "qemu/log.h"
#include "trace.h"
#include "qapi/error.h"
#include "sysemu/sysemu.h"
#include "hw/sysbus.h"
#include "hw/registerfields.h"
#include "hw/misc/armsse-mhu.h"
REG32(CPU0INTR_STAT, 0x0)
REG32(CPU0INTR_SET, 0x4)
REG32(CPU0INTR_CLR, 0x8)
REG32(CPU1INTR_STAT, 0x10)
REG32(CPU1INTR_SET, 0x14)
REG32(CPU1INTR_CLR, 0x18)
REG32(PID4, 0xfd0)
REG32(PID5, 0xfd4)
REG32(PID6, 0xfd8)
REG32(PID7, 0xfdc)
REG32(PID0, 0xfe0)
REG32(PID1, 0xfe4)
REG32(PID2, 0xfe8)
REG32(PID3, 0xfec)
REG32(CID0, 0xff0)
REG32(CID1, 0xff4)
REG32(CID2, 0xff8)
REG32(CID3, 0xffc)
/* Valid bits in the interrupt registers. If any are set the IRQ is raised */
#define INTR_MASK 0xf
/* PID/CID values */
static const int armsse_mhu_id[] = {
0x04, 0x00, 0x00, 0x00, /* PID4..PID7 */
0x56, 0xb8, 0x0b, 0x00, /* PID0..PID3 */
0x0d, 0xf0, 0x05, 0xb1, /* CID0..CID3 */
};
static void armsse_mhu_update(ARMSSEMHU *s)
{
qemu_set_irq(s->cpu0irq, s->cpu0intr != 0);
qemu_set_irq(s->cpu1irq, s->cpu1intr != 0);
}
static uint64_t armsse_mhu_read(void *opaque, hwaddr offset, unsigned size)
{
ARMSSEMHU *s = ARMSSE_MHU(opaque);
uint64_t r;
switch (offset) {
case A_CPU0INTR_STAT:
r = s->cpu0intr;
break;
case A_CPU1INTR_STAT:
r = s->cpu1intr;
break;
case A_PID4 ... A_CID3:
r = armsse_mhu_id[(offset - A_PID4) / 4];
break;
case A_CPU0INTR_SET:
case A_CPU0INTR_CLR:
case A_CPU1INTR_SET:
case A_CPU1INTR_CLR:
qemu_log_mask(LOG_GUEST_ERROR,
"SSE MHU: read of write-only register at offset 0x%x\n",
(int)offset);
r = 0;
break;
default:
qemu_log_mask(LOG_GUEST_ERROR,
"SSE MHU read: bad offset 0x%x\n", (int)offset);
r = 0;
break;
}
trace_armsse_mhu_read(offset, r, size);
return r;
}
static void armsse_mhu_write(void *opaque, hwaddr offset,
uint64_t value, unsigned size)
{
ARMSSEMHU *s = ARMSSE_MHU(opaque);
trace_armsse_mhu_write(offset, value, size);
switch (offset) {
case A_CPU0INTR_SET:
s->cpu0intr |= (value & INTR_MASK);
break;
case A_CPU0INTR_CLR:
s->cpu0intr &= ~(value & INTR_MASK);
break;
case A_CPU1INTR_SET:
s->cpu1intr |= (value & INTR_MASK);
break;
case A_CPU1INTR_CLR:
s->cpu1intr &= ~(value & INTR_MASK);
break;
case A_CPU0INTR_STAT:
case A_CPU1INTR_STAT:
case A_PID4 ... A_CID3:
qemu_log_mask(LOG_GUEST_ERROR,
"SSE MHU: write to read-only register at offset 0x%x\n",
(int)offset);
break;
default:
qemu_log_mask(LOG_GUEST_ERROR,
"SSE MHU write: bad offset 0x%x\n", (int)offset);
break;
}
armsse_mhu_update(s);
}
static const MemoryRegionOps armsse_mhu_ops = {
.read = armsse_mhu_read,
.write = armsse_mhu_write,
.endianness = DEVICE_LITTLE_ENDIAN,
.valid.min_access_size = 4,
.valid.max_access_size = 4,
};
static void armsse_mhu_reset(DeviceState *dev)
{
ARMSSEMHU *s = ARMSSE_MHU(dev);
s->cpu0intr = 0;
s->cpu1intr = 0;
}
static const VMStateDescription armsse_mhu_vmstate = {
.name = "armsse-mhu",
.version_id = 1,
.minimum_version_id = 1,
.fields = (VMStateField[]) {
VMSTATE_UINT32(cpu0intr, ARMSSEMHU),
VMSTATE_UINT32(cpu1intr, ARMSSEMHU),
VMSTATE_END_OF_LIST()
},
};
static void armsse_mhu_init(Object *obj)
{
SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
ARMSSEMHU *s = ARMSSE_MHU(obj);
memory_region_init_io(&s->iomem, obj, &armsse_mhu_ops,
s, "armsse-mhu", 0x1000);
sysbus_init_mmio(sbd, &s->iomem);
sysbus_init_irq(sbd, &s->cpu0irq);
sysbus_init_irq(sbd, &s->cpu1irq);
}
static void armsse_mhu_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
dc->reset = armsse_mhu_reset;
dc->vmsd = &armsse_mhu_vmstate;
}
static const TypeInfo armsse_mhu_info = {
.name = TYPE_ARMSSE_MHU,
.parent = TYPE_SYS_BUS_DEVICE,
.instance_size = sizeof(ARMSSEMHU),
.instance_init = armsse_mhu_init,
.class_init = armsse_mhu_class_init,
};
static void armsse_mhu_register_types(void)
{
type_register_static(&armsse_mhu_info);
}
type_init(armsse_mhu_register_types);