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-rw-r--r--qemu/hw/char/digic-uart.c197
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diff --git a/qemu/hw/char/digic-uart.c b/qemu/hw/char/digic-uart.c
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+++ b/qemu/hw/char/digic-uart.c
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+/*
+ * QEMU model of the Canon DIGIC UART block.
+ *
+ * Copyright (C) 2013 Antony Pavlov <antonynpavlov@gmail.com>
+ *
+ * This model is based on reverse engineering efforts
+ * made by CHDK (http://chdk.wikia.com) and
+ * Magic Lantern (http://www.magiclantern.fm) projects
+ * contributors.
+ *
+ * See "Serial terminal" docs here:
+ * http://magiclantern.wikia.com/wiki/Register_Map#Misc_Registers
+ *
+ * The QEMU model of the Milkymist UART block by Michael Walle
+ * is used as a template.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ */
+
+#include "hw/hw.h"
+#include "hw/sysbus.h"
+#include "sysemu/char.h"
+
+#include "hw/char/digic-uart.h"
+
+enum {
+ ST_RX_RDY = (1 << 0),
+ ST_TX_RDY = (1 << 1),
+};
+
+static uint64_t digic_uart_read(void *opaque, hwaddr addr,
+ unsigned size)
+{
+ DigicUartState *s = opaque;
+ uint64_t ret = 0;
+
+ addr >>= 2;
+
+ switch (addr) {
+ case R_RX:
+ s->reg_st &= ~(ST_RX_RDY);
+ ret = s->reg_rx;
+ break;
+
+ case R_ST:
+ ret = s->reg_st;
+ break;
+
+ default:
+ qemu_log_mask(LOG_UNIMP,
+ "digic-uart: read access to unknown register 0x"
+ TARGET_FMT_plx, addr << 2);
+ }
+
+ return ret;
+}
+
+static void digic_uart_write(void *opaque, hwaddr addr, uint64_t value,
+ unsigned size)
+{
+ DigicUartState *s = opaque;
+ unsigned char ch = value;
+
+ addr >>= 2;
+
+ switch (addr) {
+ case R_TX:
+ if (s->chr) {
+ qemu_chr_fe_write_all(s->chr, &ch, 1);
+ }
+ break;
+
+ case R_ST:
+ /*
+ * Ignore write to R_ST.
+ *
+ * The point is that this register is actively used
+ * during receiving and transmitting symbols,
+ * but we don't know the function of most of bits.
+ *
+ * Ignoring writes to R_ST is only a simplification
+ * of the model. It has no perceptible side effects
+ * for existing guests.
+ */
+ break;
+
+ default:
+ qemu_log_mask(LOG_UNIMP,
+ "digic-uart: write access to unknown register 0x"
+ TARGET_FMT_plx, addr << 2);
+ }
+}
+
+static const MemoryRegionOps uart_mmio_ops = {
+ .read = digic_uart_read,
+ .write = digic_uart_write,
+ .valid = {
+ .min_access_size = 4,
+ .max_access_size = 4,
+ },
+ .endianness = DEVICE_NATIVE_ENDIAN,
+};
+
+static int uart_can_rx(void *opaque)
+{
+ DigicUartState *s = opaque;
+
+ return !(s->reg_st & ST_RX_RDY);
+}
+
+static void uart_rx(void *opaque, const uint8_t *buf, int size)
+{
+ DigicUartState *s = opaque;
+
+ assert(uart_can_rx(opaque));
+
+ s->reg_st |= ST_RX_RDY;
+ s->reg_rx = *buf;
+}
+
+static void uart_event(void *opaque, int event)
+{
+}
+
+static void digic_uart_reset(DeviceState *d)
+{
+ DigicUartState *s = DIGIC_UART(d);
+
+ s->reg_rx = 0;
+ s->reg_st = ST_TX_RDY;
+}
+
+static void digic_uart_realize(DeviceState *dev, Error **errp)
+{
+ DigicUartState *s = DIGIC_UART(dev);
+
+ /* FIXME use a qdev chardev prop instead of qemu_char_get_next_serial() */
+ 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 digic_uart_init(Object *obj)
+{
+ DigicUartState *s = DIGIC_UART(obj);
+
+ memory_region_init_io(&s->regs_region, OBJECT(s), &uart_mmio_ops, s,
+ TYPE_DIGIC_UART, 0x18);
+ sysbus_init_mmio(SYS_BUS_DEVICE(obj), &s->regs_region);
+}
+
+static const VMStateDescription vmstate_digic_uart = {
+ .name = "digic-uart",
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .fields = (VMStateField[]) {
+ VMSTATE_UINT32(reg_rx, DigicUartState),
+ VMSTATE_UINT32(reg_st, DigicUartState),
+ VMSTATE_END_OF_LIST()
+ }
+};
+
+static void digic_uart_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+
+ dc->realize = digic_uart_realize;
+ dc->reset = digic_uart_reset;
+ dc->vmsd = &vmstate_digic_uart;
+ /* Reason: realize() method uses qemu_char_get_next_serial() */
+ dc->cannot_instantiate_with_device_add_yet = true;
+}
+
+static const TypeInfo digic_uart_info = {
+ .name = TYPE_DIGIC_UART,
+ .parent = TYPE_SYS_BUS_DEVICE,
+ .instance_size = sizeof(DigicUartState),
+ .instance_init = digic_uart_init,
+ .class_init = digic_uart_class_init,
+};
+
+static void digic_uart_register_types(void)
+{
+ type_register_static(&digic_uart_info);
+}
+
+type_init(digic_uart_register_types)