qemu/hw/gpio/pl061.c
Wei Huang b527db44ad ARM: PL061: Clear PL061 device state after reset
Current QEMU doesn't clear PL061 state after reset. This causes a
weird issue with guest reboot via GPIO. Here is the device state
with two reboot requests:

  (PL061State fields)           data   old_in_data   istate
VM boot                         0      0             0
After 1st ACPI reboot request   8      8             8
After VM PL061 driver ACK       8      8             0
After VM reboot                 8      8             0
------------------------------------------------------------
2nd ACPI reboot request         8

In the second reboot request above, because the old_in_data field is 8,
QEMU decides that there is a pending edge IRQ already (see
pl061_update()) in input; so it doesn't raise up IRQ again. As a result
the second reboot request is lost. The correct way is to clear PL061
device state after reset.

The default reset state is found from the documents listed below. Per
Peter's suggestion that QEMU automatically calls reset function after
device initialization, this patch removes calling pl061_reset() from
pl061_initfn().

Reference:
[1] PL061 Technical Reference Manual
[2] Stellaris LM3S8962 Microcontroller Data Sheet
[3] Stellaris LM3S5P31 Microcontroller Data Sheet

Signed-off-by: Wei Huang <wei@redhat.com>
Message-id: 1455729552-28026-2-git-send-email-wei@redhat.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-02-18 14:26:33 +00:00

392 lines
10 KiB
C

/*
* Arm PrimeCell PL061 General Purpose IO with additional
* Luminary Micro Stellaris bits.
*
* Copyright (c) 2007 CodeSourcery.
* Written by Paul Brook
*
* This code is licensed under the GPL.
*/
#include "qemu/osdep.h"
#include "hw/sysbus.h"
//#define DEBUG_PL061 1
#ifdef DEBUG_PL061
#define DPRINTF(fmt, ...) \
do { printf("pl061: " fmt , ## __VA_ARGS__); } while (0)
#define BADF(fmt, ...) \
do { fprintf(stderr, "pl061: error: " fmt , ## __VA_ARGS__); exit(1);} while (0)
#else
#define DPRINTF(fmt, ...) do {} while(0)
#define BADF(fmt, ...) \
do { fprintf(stderr, "pl061: error: " fmt , ## __VA_ARGS__);} while (0)
#endif
static const uint8_t pl061_id[12] =
{ 0x00, 0x00, 0x00, 0x00, 0x61, 0x10, 0x04, 0x00, 0x0d, 0xf0, 0x05, 0xb1 };
static const uint8_t pl061_id_luminary[12] =
{ 0x00, 0x00, 0x00, 0x00, 0x61, 0x00, 0x18, 0x01, 0x0d, 0xf0, 0x05, 0xb1 };
#define TYPE_PL061 "pl061"
#define PL061(obj) OBJECT_CHECK(PL061State, (obj), TYPE_PL061)
typedef struct PL061State {
SysBusDevice parent_obj;
MemoryRegion iomem;
uint32_t locked;
uint32_t data;
uint32_t old_out_data;
uint32_t old_in_data;
uint32_t dir;
uint32_t isense;
uint32_t ibe;
uint32_t iev;
uint32_t im;
uint32_t istate;
uint32_t afsel;
uint32_t dr2r;
uint32_t dr4r;
uint32_t dr8r;
uint32_t odr;
uint32_t pur;
uint32_t pdr;
uint32_t slr;
uint32_t den;
uint32_t cr;
uint32_t float_high;
uint32_t amsel;
qemu_irq irq;
qemu_irq out[8];
const unsigned char *id;
} PL061State;
static const VMStateDescription vmstate_pl061 = {
.name = "pl061",
.version_id = 3,
.minimum_version_id = 3,
.fields = (VMStateField[]) {
VMSTATE_UINT32(locked, PL061State),
VMSTATE_UINT32(data, PL061State),
VMSTATE_UINT32(old_out_data, PL061State),
VMSTATE_UINT32(old_in_data, PL061State),
VMSTATE_UINT32(dir, PL061State),
VMSTATE_UINT32(isense, PL061State),
VMSTATE_UINT32(ibe, PL061State),
VMSTATE_UINT32(iev, PL061State),
VMSTATE_UINT32(im, PL061State),
VMSTATE_UINT32(istate, PL061State),
VMSTATE_UINT32(afsel, PL061State),
VMSTATE_UINT32(dr2r, PL061State),
VMSTATE_UINT32(dr4r, PL061State),
VMSTATE_UINT32(dr8r, PL061State),
VMSTATE_UINT32(odr, PL061State),
VMSTATE_UINT32(pur, PL061State),
VMSTATE_UINT32(pdr, PL061State),
VMSTATE_UINT32(slr, PL061State),
VMSTATE_UINT32(den, PL061State),
VMSTATE_UINT32(cr, PL061State),
VMSTATE_UINT32(float_high, PL061State),
VMSTATE_UINT32_V(amsel, PL061State, 2),
VMSTATE_END_OF_LIST()
}
};
static void pl061_update(PL061State *s)
{
uint8_t changed;
uint8_t mask;
uint8_t out;
int i;
DPRINTF("dir = %d, data = %d\n", s->dir, s->data);
/* Outputs float high. */
/* FIXME: This is board dependent. */
out = (s->data & s->dir) | ~s->dir;
changed = s->old_out_data ^ out;
if (changed) {
s->old_out_data = out;
for (i = 0; i < 8; i++) {
mask = 1 << i;
if (changed & mask) {
DPRINTF("Set output %d = %d\n", i, (out & mask) != 0);
qemu_set_irq(s->out[i], (out & mask) != 0);
}
}
}
/* Inputs */
changed = (s->old_in_data ^ s->data) & ~s->dir;
if (changed) {
s->old_in_data = s->data;
for (i = 0; i < 8; i++) {
mask = 1 << i;
if (changed & mask) {
DPRINTF("Changed input %d = %d\n", i, (s->data & mask) != 0);
if (!(s->isense & mask)) {
/* Edge interrupt */
if (s->ibe & mask) {
/* Any edge triggers the interrupt */
s->istate |= mask;
} else {
/* Edge is selected by IEV */
s->istate |= ~(s->data ^ s->iev) & mask;
}
}
}
}
}
/* Level interrupt */
s->istate |= ~(s->data ^ s->iev) & s->isense;
DPRINTF("istate = %02X\n", s->istate);
qemu_set_irq(s->irq, (s->istate & s->im) != 0);
}
static uint64_t pl061_read(void *opaque, hwaddr offset,
unsigned size)
{
PL061State *s = (PL061State *)opaque;
if (offset >= 0xfd0 && offset < 0x1000) {
return s->id[(offset - 0xfd0) >> 2];
}
if (offset < 0x400) {
return s->data & (offset >> 2);
}
switch (offset) {
case 0x400: /* Direction */
return s->dir;
case 0x404: /* Interrupt sense */
return s->isense;
case 0x408: /* Interrupt both edges */
return s->ibe;
case 0x40c: /* Interrupt event */
return s->iev;
case 0x410: /* Interrupt mask */
return s->im;
case 0x414: /* Raw interrupt status */
return s->istate;
case 0x418: /* Masked interrupt status */
return s->istate & s->im;
case 0x420: /* Alternate function select */
return s->afsel;
case 0x500: /* 2mA drive */
return s->dr2r;
case 0x504: /* 4mA drive */
return s->dr4r;
case 0x508: /* 8mA drive */
return s->dr8r;
case 0x50c: /* Open drain */
return s->odr;
case 0x510: /* Pull-up */
return s->pur;
case 0x514: /* Pull-down */
return s->pdr;
case 0x518: /* Slew rate control */
return s->slr;
case 0x51c: /* Digital enable */
return s->den;
case 0x520: /* Lock */
return s->locked;
case 0x524: /* Commit */
return s->cr;
case 0x528: /* Analog mode select */
return s->amsel;
default:
qemu_log_mask(LOG_GUEST_ERROR,
"pl061_read: Bad offset %x\n", (int)offset);
return 0;
}
}
static void pl061_write(void *opaque, hwaddr offset,
uint64_t value, unsigned size)
{
PL061State *s = (PL061State *)opaque;
uint8_t mask;
if (offset < 0x400) {
mask = (offset >> 2) & s->dir;
s->data = (s->data & ~mask) | (value & mask);
pl061_update(s);
return;
}
switch (offset) {
case 0x400: /* Direction */
s->dir = value & 0xff;
break;
case 0x404: /* Interrupt sense */
s->isense = value & 0xff;
break;
case 0x408: /* Interrupt both edges */
s->ibe = value & 0xff;
break;
case 0x40c: /* Interrupt event */
s->iev = value & 0xff;
break;
case 0x410: /* Interrupt mask */
s->im = value & 0xff;
break;
case 0x41c: /* Interrupt clear */
s->istate &= ~value;
break;
case 0x420: /* Alternate function select */
mask = s->cr;
s->afsel = (s->afsel & ~mask) | (value & mask);
break;
case 0x500: /* 2mA drive */
s->dr2r = value & 0xff;
break;
case 0x504: /* 4mA drive */
s->dr4r = value & 0xff;
break;
case 0x508: /* 8mA drive */
s->dr8r = value & 0xff;
break;
case 0x50c: /* Open drain */
s->odr = value & 0xff;
break;
case 0x510: /* Pull-up */
s->pur = value & 0xff;
break;
case 0x514: /* Pull-down */
s->pdr = value & 0xff;
break;
case 0x518: /* Slew rate control */
s->slr = value & 0xff;
break;
case 0x51c: /* Digital enable */
s->den = value & 0xff;
break;
case 0x520: /* Lock */
s->locked = (value != 0xacce551);
break;
case 0x524: /* Commit */
if (!s->locked)
s->cr = value & 0xff;
break;
case 0x528:
s->amsel = value & 0xff;
break;
default:
qemu_log_mask(LOG_GUEST_ERROR,
"pl061_write: Bad offset %x\n", (int)offset);
}
pl061_update(s);
}
static void pl061_reset(DeviceState *dev)
{
PL061State *s = PL061(dev);
/* reset values from PL061 TRM, Stellaris LM3S5P31 & LM3S8962 Data Sheet */
s->data = 0;
s->old_out_data = 0;
s->old_in_data = 0;
s->dir = 0;
s->isense = 0;
s->ibe = 0;
s->iev = 0;
s->im = 0;
s->istate = 0;
s->afsel = 0;
s->dr2r = 0xff;
s->dr4r = 0;
s->dr8r = 0;
s->odr = 0;
s->pur = 0;
s->pdr = 0;
s->slr = 0;
s->den = 0;
s->locked = 1;
s->cr = 0xff;
s->amsel = 0;
}
static void pl061_set_irq(void * opaque, int irq, int level)
{
PL061State *s = (PL061State *)opaque;
uint8_t mask;
mask = 1 << irq;
if ((s->dir & mask) == 0) {
s->data &= ~mask;
if (level)
s->data |= mask;
pl061_update(s);
}
}
static const MemoryRegionOps pl061_ops = {
.read = pl061_read,
.write = pl061_write,
.endianness = DEVICE_NATIVE_ENDIAN,
};
static int pl061_initfn(SysBusDevice *sbd)
{
DeviceState *dev = DEVICE(sbd);
PL061State *s = PL061(dev);
memory_region_init_io(&s->iomem, OBJECT(s), &pl061_ops, s, "pl061", 0x1000);
sysbus_init_mmio(sbd, &s->iomem);
sysbus_init_irq(sbd, &s->irq);
qdev_init_gpio_in(dev, pl061_set_irq, 8);
qdev_init_gpio_out(dev, s->out, 8);
return 0;
}
static void pl061_luminary_init(Object *obj)
{
PL061State *s = PL061(obj);
s->id = pl061_id_luminary;
}
static void pl061_init(Object *obj)
{
PL061State *s = PL061(obj);
s->id = pl061_id;
}
static void pl061_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
k->init = pl061_initfn;
dc->vmsd = &vmstate_pl061;
dc->reset = &pl061_reset;
}
static const TypeInfo pl061_info = {
.name = TYPE_PL061,
.parent = TYPE_SYS_BUS_DEVICE,
.instance_size = sizeof(PL061State),
.instance_init = pl061_init,
.class_init = pl061_class_init,
};
static const TypeInfo pl061_luminary_info = {
.name = "pl061_luminary",
.parent = TYPE_PL061,
.instance_init = pl061_luminary_init,
};
static void pl061_register_types(void)
{
type_register_static(&pl061_info);
type_register_static(&pl061_luminary_info);
}
type_init(pl061_register_types)