qemu/hw/char/milkymist-uart.c
Juan Quintela 35d08458a9 savevm: Remove all the unneeded version_minimum_id_old (rest)
After previous Peter patch, they are redundant.  This way we don't
assign them except when needed.  Once there, there were lots of case
where the ".fields" indentation was wrong:

     .fields = (VMStateField []) {
and
     .fields =      (VMStateField []) {

Change all the combinations to:

     .fields = (VMStateField[]){

The biggest problem (appart from aesthetics) was that checkpatch complained
when we copy&pasted the code from one place to another.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
2014-05-14 15:24:51 +02:00

253 lines
5.9 KiB
C

/*
* QEMU model of the Milkymist UART block.
*
* Copyright (c) 2010 Michael Walle <michael@walle.cc>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
*
*
* Specification available at:
* http://www.milkymist.org/socdoc/uart.pdf
*/
#include "hw/hw.h"
#include "hw/sysbus.h"
#include "trace.h"
#include "sysemu/char.h"
#include "qemu/error-report.h"
enum {
R_RXTX = 0,
R_DIV,
R_STAT,
R_CTRL,
R_DBG,
R_MAX
};
enum {
STAT_THRE = (1<<0),
STAT_RX_EVT = (1<<1),
STAT_TX_EVT = (1<<2),
};
enum {
CTRL_RX_IRQ_EN = (1<<0),
CTRL_TX_IRQ_EN = (1<<1),
CTRL_THRU_EN = (1<<2),
};
enum {
DBG_BREAK_EN = (1<<0),
};
#define TYPE_MILKYMIST_UART "milkymist-uart"
#define MILKYMIST_UART(obj) \
OBJECT_CHECK(MilkymistUartState, (obj), TYPE_MILKYMIST_UART)
struct MilkymistUartState {
SysBusDevice parent_obj;
MemoryRegion regs_region;
CharDriverState *chr;
qemu_irq irq;
uint32_t regs[R_MAX];
};
typedef struct MilkymistUartState MilkymistUartState;
static void uart_update_irq(MilkymistUartState *s)
{
int rx_event = s->regs[R_STAT] & STAT_RX_EVT;
int tx_event = s->regs[R_STAT] & STAT_TX_EVT;
int rx_irq_en = s->regs[R_CTRL] & CTRL_RX_IRQ_EN;
int tx_irq_en = s->regs[R_CTRL] & CTRL_TX_IRQ_EN;
if ((rx_irq_en && rx_event) || (tx_irq_en && tx_event)) {
trace_milkymist_uart_raise_irq();
qemu_irq_raise(s->irq);
} else {
trace_milkymist_uart_lower_irq();
qemu_irq_lower(s->irq);
}
}
static uint64_t uart_read(void *opaque, hwaddr addr,
unsigned size)
{
MilkymistUartState *s = opaque;
uint32_t r = 0;
addr >>= 2;
switch (addr) {
case R_RXTX:
r = s->regs[addr];
break;
case R_DIV:
case R_STAT:
case R_CTRL:
case R_DBG:
r = s->regs[addr];
break;
default:
error_report("milkymist_uart: read access to unknown register 0x"
TARGET_FMT_plx, addr << 2);
break;
}
trace_milkymist_uart_memory_read(addr << 2, r);
return r;
}
static void uart_write(void *opaque, hwaddr addr, uint64_t value,
unsigned size)
{
MilkymistUartState *s = opaque;
unsigned char ch = value;
trace_milkymist_uart_memory_write(addr, value);
addr >>= 2;
switch (addr) {
case R_RXTX:
if (s->chr) {
qemu_chr_fe_write_all(s->chr, &ch, 1);
}
s->regs[R_STAT] |= STAT_TX_EVT;
break;
case R_DIV:
case R_CTRL:
case R_DBG:
s->regs[addr] = value;
break;
case R_STAT:
/* write one to clear bits */
s->regs[addr] &= ~(value & (STAT_RX_EVT | STAT_TX_EVT));
qemu_chr_accept_input(s->chr);
break;
default:
error_report("milkymist_uart: write access to unknown register 0x"
TARGET_FMT_plx, addr << 2);
break;
}
uart_update_irq(s);
}
static const MemoryRegionOps uart_mmio_ops = {
.read = uart_read,
.write = uart_write,
.valid = {
.min_access_size = 4,
.max_access_size = 4,
},
.endianness = DEVICE_NATIVE_ENDIAN,
};
static void uart_rx(void *opaque, const uint8_t *buf, int size)
{
MilkymistUartState *s = opaque;
assert(!(s->regs[R_STAT] & STAT_RX_EVT));
s->regs[R_STAT] |= STAT_RX_EVT;
s->regs[R_RXTX] = *buf;
uart_update_irq(s);
}
static int uart_can_rx(void *opaque)
{
MilkymistUartState *s = opaque;
return !(s->regs[R_STAT] & STAT_RX_EVT);
}
static void uart_event(void *opaque, int event)
{
}
static void milkymist_uart_reset(DeviceState *d)
{
MilkymistUartState *s = MILKYMIST_UART(d);
int i;
for (i = 0; i < R_MAX; i++) {
s->regs[i] = 0;
}
/* THRE is always set */
s->regs[R_STAT] = STAT_THRE;
}
static void milkymist_uart_realize(DeviceState *dev, Error **errp)
{
MilkymistUartState *s = MILKYMIST_UART(dev);
s->chr = qemu_char_get_next_serial();
if (s->chr) {
qemu_chr_add_handlers(s->chr, uart_can_rx, uart_rx, uart_event, s);
}
}
static void milkymist_uart_init(Object *obj)
{
SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
MilkymistUartState *s = MILKYMIST_UART(obj);
sysbus_init_irq(sbd, &s->irq);
memory_region_init_io(&s->regs_region, OBJECT(s), &uart_mmio_ops, s,
"milkymist-uart", R_MAX * 4);
sysbus_init_mmio(sbd, &s->regs_region);
}
static const VMStateDescription vmstate_milkymist_uart = {
.name = "milkymist-uart",
.version_id = 1,
.minimum_version_id = 1,
.fields = (VMStateField[]) {
VMSTATE_UINT32_ARRAY(regs, MilkymistUartState, R_MAX),
VMSTATE_END_OF_LIST()
}
};
static void milkymist_uart_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
dc->realize = milkymist_uart_realize;
dc->reset = milkymist_uart_reset;
dc->vmsd = &vmstate_milkymist_uart;
}
static const TypeInfo milkymist_uart_info = {
.name = TYPE_MILKYMIST_UART,
.parent = TYPE_SYS_BUS_DEVICE,
.instance_size = sizeof(MilkymistUartState),
.instance_init = milkymist_uart_init,
.class_init = milkymist_uart_class_init,
};
static void milkymist_uart_register_types(void)
{
type_register_static(&milkymist_uart_info);
}
type_init(milkymist_uart_register_types)