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-rw-r--r--hw/char/goldfish_tty.c285
1 files changed, 285 insertions, 0 deletions
diff --git a/hw/char/goldfish_tty.c b/hw/char/goldfish_tty.c
new file mode 100644
index 0000000000..8365a18761
--- /dev/null
+++ b/hw/char/goldfish_tty.c
@@ -0,0 +1,285 @@
+/*
+ * SPDX-License-Identifer: GPL-2.0-or-later
+ *
+ * Goldfish TTY
+ *
+ * (c) 2020 Laurent Vivier <laurent@vivier.eu>
+ *
+ */
+
+#include "qemu/osdep.h"
+#include "hw/irq.h"
+#include "hw/qdev-properties-system.h"
+#include "hw/sysbus.h"
+#include "migration/vmstate.h"
+#include "chardev/char-fe.h"
+#include "qemu/log.h"
+#include "trace.h"
+#include "exec/address-spaces.h"
+#include "hw/char/goldfish_tty.h"
+
+#define GOLDFISH_TTY_VERSION 1
+
+/* registers */
+
+enum {
+ REG_PUT_CHAR = 0x00,
+ REG_BYTES_READY = 0x04,
+ REG_CMD = 0x08,
+ REG_DATA_PTR = 0x10,
+ REG_DATA_LEN = 0x14,
+ REG_DATA_PTR_HIGH = 0x18,
+ REG_VERSION = 0x20,
+};
+
+/* commands */
+
+enum {
+ CMD_INT_DISABLE = 0x00,
+ CMD_INT_ENABLE = 0x01,
+ CMD_WRITE_BUFFER = 0x02,
+ CMD_READ_BUFFER = 0x03,
+};
+
+static uint64_t goldfish_tty_read(void *opaque, hwaddr addr,
+ unsigned size)
+{
+ GoldfishTTYState *s = opaque;
+ uint64_t value = 0;
+
+ switch (addr) {
+ case REG_BYTES_READY:
+ value = fifo8_num_used(&s->rx_fifo);
+ break;
+ case REG_VERSION:
+ value = GOLDFISH_TTY_VERSION;
+ break;
+ default:
+ qemu_log_mask(LOG_UNIMP,
+ "%s: unimplemented register read 0x%02"HWADDR_PRIx"\n",
+ __func__, addr);
+ break;
+ }
+
+ trace_goldfish_tty_read(s, addr, size, value);
+
+ return value;
+}
+
+static void goldfish_tty_cmd(GoldfishTTYState *s, uint32_t cmd)
+{
+ uint32_t to_copy;
+ uint8_t *buf;
+ uint8_t data_out[GOLFISH_TTY_BUFFER_SIZE];
+ int len;
+ uint64_t ptr;
+
+ switch (cmd) {
+ case CMD_INT_DISABLE:
+ if (s->int_enabled) {
+ if (!fifo8_is_empty(&s->rx_fifo)) {
+ qemu_set_irq(s->irq, 0);
+ }
+ s->int_enabled = false;
+ }
+ break;
+ case CMD_INT_ENABLE:
+ if (!s->int_enabled) {
+ if (!fifo8_is_empty(&s->rx_fifo)) {
+ qemu_set_irq(s->irq, 1);
+ }
+ s->int_enabled = true;
+ }
+ break;
+ case CMD_WRITE_BUFFER:
+ len = s->data_len;
+ ptr = s->data_ptr;
+ while (len) {
+ to_copy = MIN(GOLFISH_TTY_BUFFER_SIZE, len);
+
+ address_space_rw(&address_space_memory, ptr,
+ MEMTXATTRS_UNSPECIFIED, data_out, to_copy, 0);
+ qemu_chr_fe_write_all(&s->chr, data_out, to_copy);
+
+ len -= to_copy;
+ ptr += to_copy;
+ }
+ break;
+ case CMD_READ_BUFFER:
+ len = s->data_len;
+ ptr = s->data_ptr;
+ while (len && !fifo8_is_empty(&s->rx_fifo)) {
+ buf = (uint8_t *)fifo8_pop_buf(&s->rx_fifo, len, &to_copy);
+ address_space_rw(&address_space_memory, ptr,
+ MEMTXATTRS_UNSPECIFIED, buf, to_copy, 1);
+
+ len -= to_copy;
+ ptr += to_copy;
+ }
+ if (s->int_enabled && fifo8_is_empty(&s->rx_fifo)) {
+ qemu_set_irq(s->irq, 0);
+ }
+ break;
+ }
+}
+
+static void goldfish_tty_write(void *opaque, hwaddr addr,
+ uint64_t value, unsigned size)
+{
+ GoldfishTTYState *s = opaque;
+ unsigned char c;
+
+ trace_goldfish_tty_write(s, addr, size, value);
+
+ switch (addr) {
+ case REG_PUT_CHAR:
+ c = value;
+ qemu_chr_fe_write_all(&s->chr, &c, sizeof(c));
+ break;
+ case REG_CMD:
+ goldfish_tty_cmd(s, value);
+ break;
+ case REG_DATA_PTR:
+ s->data_ptr = value;
+ break;
+ case REG_DATA_PTR_HIGH:
+ s->data_ptr = deposit64(s->data_ptr, 32, 32, value);
+ break;
+ case REG_DATA_LEN:
+ s->data_len = value;
+ break;
+ default:
+ qemu_log_mask(LOG_UNIMP,
+ "%s: unimplemented register write 0x%02"HWADDR_PRIx"\n",
+ __func__, addr);
+ break;
+ }
+}
+
+static const MemoryRegionOps goldfish_tty_ops = {
+ .read = goldfish_tty_read,
+ .write = goldfish_tty_write,
+ .endianness = DEVICE_NATIVE_ENDIAN,
+ .valid.max_access_size = 4,
+ .impl.max_access_size = 4,
+ .impl.min_access_size = 4,
+};
+
+static int goldfish_tty_can_receive(void *opaque)
+{
+ GoldfishTTYState *s = opaque;
+ int available = fifo8_num_free(&s->rx_fifo);
+
+ trace_goldfish_tty_can_receive(s, available);
+
+ return available;
+}
+
+static void goldfish_tty_receive(void *opaque, const uint8_t *buffer, int size)
+{
+ GoldfishTTYState *s = opaque;
+
+ trace_goldfish_tty_receive(s, size);
+
+ g_assert(size <= fifo8_num_free(&s->rx_fifo));
+
+ fifo8_push_all(&s->rx_fifo, buffer, size);
+
+ if (s->int_enabled && !fifo8_is_empty(&s->rx_fifo)) {
+ qemu_set_irq(s->irq, 1);
+ }
+}
+
+static void goldfish_tty_reset(DeviceState *dev)
+{
+ GoldfishTTYState *s = GOLDFISH_TTY(dev);
+
+ trace_goldfish_tty_reset(s);
+
+ fifo8_reset(&s->rx_fifo);
+ s->int_enabled = false;
+ s->data_ptr = 0;
+ s->data_len = 0;
+}
+
+static void goldfish_tty_realize(DeviceState *dev, Error **errp)
+{
+ GoldfishTTYState *s = GOLDFISH_TTY(dev);
+
+ trace_goldfish_tty_realize(s);
+
+ fifo8_create(&s->rx_fifo, GOLFISH_TTY_BUFFER_SIZE);
+ memory_region_init_io(&s->iomem, OBJECT(s), &goldfish_tty_ops, s,
+ "goldfish_tty", 0x24);
+
+ if (qemu_chr_fe_backend_connected(&s->chr)) {
+ qemu_chr_fe_set_handlers(&s->chr, goldfish_tty_can_receive,
+ goldfish_tty_receive, NULL, NULL,
+ s, NULL, true);
+ }
+}
+
+static void goldfish_tty_unrealize(DeviceState *dev)
+{
+ GoldfishTTYState *s = GOLDFISH_TTY(dev);
+
+ trace_goldfish_tty_unrealize(s);
+
+ fifo8_destroy(&s->rx_fifo);
+}
+
+static const VMStateDescription vmstate_goldfish_tty = {
+ .name = "goldfish_tty",
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .fields = (VMStateField[]) {
+ VMSTATE_UINT32(data_len, GoldfishTTYState),
+ VMSTATE_UINT64(data_ptr, GoldfishTTYState),
+ VMSTATE_BOOL(int_enabled, GoldfishTTYState),
+ VMSTATE_FIFO8(rx_fifo, GoldfishTTYState),
+ VMSTATE_END_OF_LIST()
+ }
+};
+
+static Property goldfish_tty_properties[] = {
+ DEFINE_PROP_CHR("chardev", GoldfishTTYState, chr),
+ DEFINE_PROP_END_OF_LIST(),
+};
+
+static void goldfish_tty_instance_init(Object *obj)
+{
+ SysBusDevice *dev = SYS_BUS_DEVICE(obj);
+ GoldfishTTYState *s = GOLDFISH_TTY(obj);
+
+ trace_goldfish_tty_instance_init(s);
+
+ sysbus_init_mmio(dev, &s->iomem);
+ sysbus_init_irq(dev, &s->irq);
+}
+
+static void goldfish_tty_class_init(ObjectClass *oc, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(oc);
+
+ device_class_set_props(dc, goldfish_tty_properties);
+ dc->reset = goldfish_tty_reset;
+ dc->realize = goldfish_tty_realize;
+ dc->unrealize = goldfish_tty_unrealize;
+ dc->vmsd = &vmstate_goldfish_tty;
+ set_bit(DEVICE_CATEGORY_INPUT, dc->categories);
+}
+
+static const TypeInfo goldfish_tty_info = {
+ .name = TYPE_GOLDFISH_TTY,
+ .parent = TYPE_SYS_BUS_DEVICE,
+ .class_init = goldfish_tty_class_init,
+ .instance_init = goldfish_tty_instance_init,
+ .instance_size = sizeof(GoldfishTTYState),
+};
+
+static void goldfish_tty_register_types(void)
+{
+ type_register_static(&goldfish_tty_info);
+}
+
+type_init(goldfish_tty_register_types)