--- /dev/null
+/*
+ * QEMU model of Xilinx uartlite.
+ *
+ * Copyright (c) 2009 Edgar E. Iglesias.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "hw/sysbus.h"
+#include "sysemu/char.h"
+
+#define DUART(x)
+
+#define R_RX 0
+#define R_TX 1
+#define R_STATUS 2
+#define R_CTRL 3
+#define R_MAX 4
+
+#define STATUS_RXVALID 0x01
+#define STATUS_RXFULL 0x02
+#define STATUS_TXEMPTY 0x04
+#define STATUS_TXFULL 0x08
+#define STATUS_IE 0x10
+#define STATUS_OVERRUN 0x20
+#define STATUS_FRAME 0x40
+#define STATUS_PARITY 0x80
+
+#define CONTROL_RST_TX 0x01
+#define CONTROL_RST_RX 0x02
+#define CONTROL_IE 0x10
+
+#define TYPE_XILINX_UARTLITE "xlnx.xps-uartlite"
+#define XILINX_UARTLITE(obj) \
+ OBJECT_CHECK(XilinxUARTLite, (obj), TYPE_XILINX_UARTLITE)
+
+typedef struct XilinxUARTLite {
+ SysBusDevice parent_obj;
+
+ MemoryRegion mmio;
+ CharDriverState *chr;
+ qemu_irq irq;
+
+ uint8_t rx_fifo[8];
+ unsigned int rx_fifo_pos;
+ unsigned int rx_fifo_len;
+
+ uint32_t regs[R_MAX];
+} XilinxUARTLite;
+
+static void uart_update_irq(XilinxUARTLite *s)
+{
+ unsigned int irq;
+
+ if (s->rx_fifo_len)
+ s->regs[R_STATUS] |= STATUS_IE;
+
+ irq = (s->regs[R_STATUS] & STATUS_IE) && (s->regs[R_CTRL] & CONTROL_IE);
+ qemu_set_irq(s->irq, irq);
+}
+
+static void uart_update_status(XilinxUARTLite *s)
+{
+ uint32_t r;
+
+ r = s->regs[R_STATUS];
+ r &= ~7;
+ r |= 1 << 2; /* Tx fifo is always empty. We are fast :) */
+ r |= (s->rx_fifo_len == sizeof (s->rx_fifo)) << 1;
+ r |= (!!s->rx_fifo_len);
+ s->regs[R_STATUS] = r;
+}
+
+static void xilinx_uartlite_reset(DeviceState *dev)
+{
+ uart_update_status(XILINX_UARTLITE(dev));
+}
+
+static uint64_t
+uart_read(void *opaque, hwaddr addr, unsigned int size)
+{
+ XilinxUARTLite *s = opaque;
+ uint32_t r = 0;
+ addr >>= 2;
+ switch (addr)
+ {
+ case R_RX:
+ r = s->rx_fifo[(s->rx_fifo_pos - s->rx_fifo_len) & 7];
+ if (s->rx_fifo_len)
+ s->rx_fifo_len--;
+ uart_update_status(s);
+ uart_update_irq(s);
+ qemu_chr_accept_input(s->chr);
+ break;
+
+ default:
+ if (addr < ARRAY_SIZE(s->regs))
+ r = s->regs[addr];
+ DUART(qemu_log("%s addr=%x v=%x\n", __func__, addr, r));
+ break;
+ }
+ return r;
+}
+
+static void
+uart_write(void *opaque, hwaddr addr,
+ uint64_t val64, unsigned int size)
+{
+ XilinxUARTLite *s = opaque;
+ uint32_t value = val64;
+ unsigned char ch = value;
+
+ addr >>= 2;
+ switch (addr)
+ {
+ case R_STATUS:
+ hw_error("write to UART STATUS?\n");
+ break;
+
+ case R_CTRL:
+ if (value & CONTROL_RST_RX) {
+ s->rx_fifo_pos = 0;
+ s->rx_fifo_len = 0;
+ }
+ s->regs[addr] = value;
+ break;
+
+ case R_TX:
+ if (s->chr)
+ qemu_chr_fe_write(s->chr, &ch, 1);
+
+ s->regs[addr] = value;
+
+ /* hax. */
+ s->regs[R_STATUS] |= STATUS_IE;
+ break;
+
+ default:
+ DUART(printf("%s addr=%x v=%x\n", __func__, addr, value));
+ if (addr < ARRAY_SIZE(s->regs))
+ s->regs[addr] = value;
+ break;
+ }
+ uart_update_status(s);
+ uart_update_irq(s);
+}
+
+static const MemoryRegionOps uart_ops = {
+ .read = uart_read,
+ .write = uart_write,
+ .endianness = DEVICE_NATIVE_ENDIAN,
+ .valid = {
+ .min_access_size = 1,
+ .max_access_size = 4
+ }
+};
+
+static void uart_rx(void *opaque, const uint8_t *buf, int size)
+{
+ XilinxUARTLite *s = opaque;
+
+ /* Got a byte. */
+ if (s->rx_fifo_len >= 8) {
+ printf("WARNING: UART dropped char.\n");
+ return;
+ }
+ s->rx_fifo[s->rx_fifo_pos] = *buf;
+ s->rx_fifo_pos++;
+ s->rx_fifo_pos &= 0x7;
+ s->rx_fifo_len++;
+
+ uart_update_status(s);
+ uart_update_irq(s);
+}
+
+static int uart_can_rx(void *opaque)
+{
+ XilinxUARTLite *s = opaque;
+
+ return s->rx_fifo_len < sizeof(s->rx_fifo);
+}
+
+static void uart_event(void *opaque, int event)
+{
+
+}
+
+static void xilinx_uartlite_realize(DeviceState *dev, Error **errp)
+{
+ XilinxUARTLite *s = XILINX_UARTLITE(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 xilinx_uartlite_init(Object *obj)
+{
+ XilinxUARTLite *s = XILINX_UARTLITE(obj);
+
+ sysbus_init_irq(SYS_BUS_DEVICE(obj), &s->irq);
+
+ memory_region_init_io(&s->mmio, obj, &uart_ops, s,
+ "xlnx.xps-uartlite", R_MAX * 4);
+ sysbus_init_mmio(SYS_BUS_DEVICE(obj), &s->mmio);
+}
+
+static void xilinx_uartlite_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+
+ dc->reset = xilinx_uartlite_reset;
+ dc->realize = xilinx_uartlite_realize;
+ /* Reason: realize() method uses qemu_char_get_next_serial() */
+ dc->cannot_instantiate_with_device_add_yet = true;
+}
+
+static const TypeInfo xilinx_uartlite_info = {
+ .name = TYPE_XILINX_UARTLITE,
+ .parent = TYPE_SYS_BUS_DEVICE,
+ .instance_size = sizeof(XilinxUARTLite),
+ .instance_init = xilinx_uartlite_init,
+ .class_init = xilinx_uartlite_class_init,
+};
+
+static void xilinx_uart_register_types(void)
+{
+ type_register_static(&xilinx_uartlite_info);
+}
+
+type_init(xilinx_uart_register_types)
Code Review / kvmfornfv.git / blobdiff