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-rw-r--r--hw/cadence_uart.c513
1 files changed, 513 insertions, 0 deletions
diff --git a/hw/cadence_uart.c b/hw/cadence_uart.c
new file mode 100644
index 0000000..d98e531
--- /dev/null
+++ b/hw/cadence_uart.c
@@ -0,0 +1,513 @@
+/*
+ * Device model for Cadence UART
+ *
+ * Copyright (c) 2010 Xilinx Inc.
+ * Copyright (c) 2012 Peter A.G. Crosthwaite (peter.crosthwaite@petalogix.com)
+ * Copyright (c) 2012 PetaLogix Pty Ltd.
+ * Written by Haibing Ma
+ * M.Habib
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "sysbus.h"
+#include "qemu-char.h"
+#include "qemu-timer.h"
+
+#ifdef CADENCE_UART_ERR_DEBUG
+#define DB_PRINT(...) do { \
+ fprintf(stderr, ": %s: ", __func__); \
+ fprintf(stderr, ## __VA_ARGS__); \
+ } while (0);
+#else
+ #define DB_PRINT(...)
+#endif
+
+#define UART_SR_INTR_RTRIG 0x00000001
+#define UART_SR_INTR_REMPTY 0x00000002
+#define UART_SR_INTR_RFUL 0x00000004
+#define UART_SR_INTR_TEMPTY 0x00000008
+#define UART_SR_INTR_TFUL 0x00000010
+/* bits fields in CSR that correlate to CISR. If any of these bits are set in
+ * SR, then the same bit in CISR is set high too */
+#define UART_SR_TO_CISR_MASK 0x0000001F
+
+#define UART_INTR_ROVR 0x00000020
+#define UART_INTR_FRAME 0x00000040
+#define UART_INTR_PARE 0x00000080
+#define UART_INTR_TIMEOUT 0x00000100
+#define UART_INTR_DMSI 0x00000200
+
+#define UART_SR_RACTIVE 0x00000400
+#define UART_SR_TACTIVE 0x00000800
+#define UART_SR_FDELT 0x00001000
+
+#define UART_CR_RXRST 0x00000001
+#define UART_CR_TXRST 0x00000002
+#define UART_CR_RX_EN 0x00000004
+#define UART_CR_RX_DIS 0x00000008
+#define UART_CR_TX_EN 0x00000010
+#define UART_CR_TX_DIS 0x00000020
+#define UART_CR_RST_TO 0x00000040
+#define UART_CR_STARTBRK 0x00000080
+#define UART_CR_STOPBRK 0x00000100
+
+#define UART_MR_CLKS 0x00000001
+#define UART_MR_CHRL 0x00000006
+#define UART_MR_CHRL_SH 1
+#define UART_MR_PAR 0x00000038
+#define UART_MR_PAR_SH 3
+#define UART_MR_NBSTOP 0x000000C0
+#define UART_MR_NBSTOP_SH 6
+#define UART_MR_CHMODE 0x00000300
+#define UART_MR_CHMODE_SH 8
+#define UART_MR_UCLKEN 0x00000400
+#define UART_MR_IRMODE 0x00000800
+
+#define UART_DATA_BITS_6 (0x3 << UART_MR_CHRL_SH)
+#define UART_DATA_BITS_7 (0x2 << UART_MR_CHRL_SH)
+#define UART_PARITY_ODD (0x1 << UART_MR_PAR_SH)
+#define UART_PARITY_EVEN (0x0 << UART_MR_PAR_SH)
+#define UART_STOP_BITS_1 (0x3 << UART_MR_NBSTOP_SH)
+#define UART_STOP_BITS_2 (0x2 << UART_MR_NBSTOP_SH)
+#define NORMAL_MODE (0x0 << UART_MR_CHMODE_SH)
+#define ECHO_MODE (0x1 << UART_MR_CHMODE_SH)
+#define LOCAL_LOOPBACK (0x2 << UART_MR_CHMODE_SH)
+#define REMOTE_LOOPBACK (0x3 << UART_MR_CHMODE_SH)
+
+#define RX_FIFO_SIZE 16
+#define TX_FIFO_SIZE 16
+#define UART_INPUT_CLK 50000000
+
+#define R_CR (0x00/4)
+#define R_MR (0x04/4)
+#define R_IER (0x08/4)
+#define R_IDR (0x0C/4)
+#define R_IMR (0x10/4)
+#define R_CISR (0x14/4)
+#define R_BRGR (0x18/4)
+#define R_RTOR (0x1C/4)
+#define R_RTRIG (0x20/4)
+#define R_MCR (0x24/4)
+#define R_MSR (0x28/4)
+#define R_SR (0x2C/4)
+#define R_TX_RX (0x30/4)
+#define R_BDIV (0x34/4)
+#define R_FDEL (0x38/4)
+#define R_PMIN (0x3C/4)
+#define R_PWID (0x40/4)
+#define R_TTRIG (0x44/4)
+
+#define R_MAX (R_TTRIG + 1)
+
+typedef struct {
+ SysBusDevice busdev;
+ MemoryRegion iomem;
+ uint32_t r[R_MAX];
+ uint8_t r_fifo[RX_FIFO_SIZE];
+ uint32_t rx_wpos;
+ uint32_t rx_count;
+ uint64_t char_tx_time;
+ CharDriverState *chr;
+ qemu_irq irq;
+ struct QEMUTimer *fifo_trigger_handle;
+ struct QEMUTimer *tx_time_handle;
+} UartState;
+
+static void uart_update_status(UartState *s)
+{
+ s->r[R_CISR] |= s->r[R_SR] & UART_SR_TO_CISR_MASK;
+ qemu_set_irq(s->irq, !!(s->r[R_IMR] & s->r[R_CISR]));
+}
+
+static void fifo_trigger_update(void *opaque)
+{
+ UartState *s = (UartState *)opaque;
+
+ s->r[R_CISR] |= UART_INTR_TIMEOUT;
+
+ uart_update_status(s);
+}
+
+static void uart_tx_redo(UartState *s)
+{
+ uint64_t new_tx_time = qemu_get_clock_ns(vm_clock);
+
+ qemu_mod_timer(s->tx_time_handle, new_tx_time + s->char_tx_time);
+
+ s->r[R_SR] |= UART_SR_INTR_TEMPTY;
+
+ uart_update_status(s);
+}
+
+static void uart_tx_write(void *opaque)
+{
+ UartState *s = (UartState *)opaque;
+
+ uart_tx_redo(s);
+}
+
+static void uart_rx_reset(UartState *s)
+{
+ s->rx_wpos = 0;
+ s->rx_count = 0;
+
+ s->r[R_SR] |= UART_SR_INTR_REMPTY;
+ s->r[R_SR] &= ~UART_SR_INTR_RFUL;
+}
+
+static void uart_tx_reset(UartState *s)
+{
+ s->r[R_SR] |= UART_SR_INTR_TEMPTY;
+ s->r[R_SR] &= ~UART_SR_INTR_TFUL;
+}
+
+static void uart_send_breaks(UartState *s)
+{
+ int break_enabled = 1;
+
+ qemu_chr_fe_ioctl(s->chr, CHR_IOCTL_SERIAL_SET_BREAK,
+ &break_enabled);
+}
+
+static void uart_parameters_setup(UartState *s)
+{
+ QEMUSerialSetParams ssp;
+ unsigned int baud_rate, packet_size;
+
+ baud_rate = (s->r[R_MR] & UART_MR_CLKS) ?
+ UART_INPUT_CLK / 8 : UART_INPUT_CLK;
+
+ ssp.speed = baud_rate / (s->r[R_BRGR] * (s->r[R_BDIV] + 1));
+ packet_size = 1;
+
+ switch (s->r[R_MR] & UART_MR_PAR) {
+ case UART_PARITY_EVEN:
+ ssp.parity = 'E';
+ packet_size++;
+ break;
+ case UART_PARITY_ODD:
+ ssp.parity = 'O';
+ packet_size++;
+ break;
+ default:
+ ssp.parity = 'N';
+ break;
+ }
+
+ switch (s->r[R_MR] & UART_MR_CHRL) {
+ case UART_DATA_BITS_6:
+ ssp.data_bits = 6;
+ break;
+ case UART_DATA_BITS_7:
+ ssp.data_bits = 7;
+ break;
+ default:
+ ssp.data_bits = 8;
+ break;
+ }
+
+ switch (s->r[R_MR] & UART_MR_NBSTOP) {
+ case UART_STOP_BITS_1:
+ ssp.stop_bits = 1;
+ break;
+ default:
+ ssp.stop_bits = 2;
+ break;
+ }
+
+ packet_size += ssp.data_bits + ssp.stop_bits;
+ s->char_tx_time = (get_ticks_per_sec() / ssp.speed) * packet_size;
+ qemu_chr_fe_ioctl(s->chr, CHR_IOCTL_SERIAL_SET_PARAMS, &ssp);
+}
+
+static int uart_can_receive(void *opaque)
+{
+ UartState *s = (UartState *)opaque;
+
+ return RX_FIFO_SIZE - s->rx_count;
+}
+
+static void uart_ctrl_update(UartState *s)
+{
+ if (s->r[R_CR] & UART_CR_TXRST) {
+ uart_tx_reset(s);
+ }
+
+ if (s->r[R_CR] & UART_CR_RXRST) {
+ uart_rx_reset(s);
+ }
+
+ s->r[R_CR] &= ~(UART_CR_TXRST | UART_CR_RXRST);
+
+ if ((s->r[R_CR] & UART_CR_TX_EN) && !(s->r[R_CR] & UART_CR_TX_DIS)) {
+ uart_tx_redo(s);
+ }
+
+ if (s->r[R_CR] & UART_CR_STARTBRK && !(s->r[R_CR] & UART_CR_STOPBRK)) {
+ uart_send_breaks(s);
+ }
+}
+
+static void uart_write_rx_fifo(void *opaque, const uint8_t *buf, int size)
+{
+ UartState *s = (UartState *)opaque;
+ uint64_t new_rx_time = qemu_get_clock_ns(vm_clock);
+ int i;
+
+ if ((s->r[R_CR] & UART_CR_RX_DIS) || !(s->r[R_CR] & UART_CR_RX_EN)) {
+ return;
+ }
+
+ s->r[R_SR] &= ~UART_SR_INTR_REMPTY;
+
+ if (s->rx_count == RX_FIFO_SIZE) {
+ s->r[R_CISR] |= UART_INTR_ROVR;
+ } else {
+ for (i = 0; i < size; i++) {
+ s->r_fifo[s->rx_wpos] = buf[i];
+ s->rx_wpos = (s->rx_wpos + 1) % RX_FIFO_SIZE;
+ s->rx_count++;
+
+ if (s->rx_count == RX_FIFO_SIZE) {
+ s->r[R_SR] |= UART_SR_INTR_RFUL;
+ break;
+ }
+
+ if (s->rx_count >= s->r[R_RTRIG]) {
+ s->r[R_SR] |= UART_SR_INTR_RTRIG;
+ }
+ }
+ qemu_mod_timer(s->fifo_trigger_handle, new_rx_time +
+ (s->char_tx_time * 4));
+ }
+ uart_update_status(s);
+}
+
+static void uart_write_tx_fifo(UartState *s, const uint8_t *buf, int size)
+{
+ if ((s->r[R_CR] & UART_CR_TX_DIS) || !(s->r[R_CR] & UART_CR_TX_EN)) {
+ return;
+ }
+
+ while (size) {
+ size -= qemu_chr_fe_write(s->chr, buf, size);
+ }
+}
+
+static void uart_receive(void *opaque, const uint8_t *buf, int size)
+{
+ UartState *s = (UartState *)opaque;
+ uint32_t ch_mode = s->r[R_MR] & UART_MR_CHMODE;
+
+ if (ch_mode == NORMAL_MODE || ch_mode == ECHO_MODE) {
+ uart_write_rx_fifo(opaque, buf, size);
+ }
+ if (ch_mode == REMOTE_LOOPBACK || ch_mode == ECHO_MODE) {
+ uart_write_tx_fifo(s, buf, size);
+ }
+}
+
+static void uart_event(void *opaque, int event)
+{
+ UartState *s = (UartState *)opaque;
+ uint8_t buf = '\0';
+
+ if (event == CHR_EVENT_BREAK) {
+ uart_write_rx_fifo(opaque, &buf, 1);
+ }
+
+ uart_update_status(s);
+}
+
+static void uart_read_rx_fifo(UartState *s, uint32_t *c)
+{
+ if ((s->r[R_CR] & UART_CR_RX_DIS) || !(s->r[R_CR] & UART_CR_RX_EN)) {
+ return;
+ }
+
+ s->r[R_SR] &= ~UART_SR_INTR_RFUL;
+
+ if (s->rx_count) {
+ uint32_t rx_rpos =
+ (RX_FIFO_SIZE + s->rx_wpos - s->rx_count) % RX_FIFO_SIZE;
+ *c = s->r_fifo[rx_rpos];
+ s->rx_count--;
+
+ if (!s->rx_count) {
+ s->r[R_SR] |= UART_SR_INTR_REMPTY;
+ }
+ } else {
+ *c = 0;
+ s->r[R_SR] |= UART_SR_INTR_REMPTY;
+ }
+
+ if (s->rx_count < s->r[R_RTRIG]) {
+ s->r[R_SR] &= ~UART_SR_INTR_RTRIG;
+ }
+ uart_update_status(s);
+}
+
+static void uart_write(void *opaque, target_phys_addr_t offset,
+ uint64_t value, unsigned size)
+{
+ UartState *s = (UartState *)opaque;
+
+ DB_PRINT(" offset:%x data:%08x\n", offset, (unsigned)value);
+ offset >>= 2;
+ switch (offset) {
+ case R_IER: /* ier (wts imr) */
+ s->r[R_IMR] |= value;
+ break;
+ case R_IDR: /* idr (wtc imr) */
+ s->r[R_IMR] &= ~value;
+ break;
+ case R_IMR: /* imr (read only) */
+ break;
+ case R_CISR: /* cisr (wtc) */
+ s->r[R_CISR] &= ~value;
+ break;
+ case R_TX_RX: /* UARTDR */
+ switch (s->r[R_MR] & UART_MR_CHMODE) {
+ case NORMAL_MODE:
+ uart_write_tx_fifo(s, (uint8_t *) &value, 1);
+ break;
+ case LOCAL_LOOPBACK:
+ uart_write_rx_fifo(opaque, (uint8_t *) &value, 1);
+ break;
+ }
+ break;
+ default:
+ s->r[offset] = value;
+ }
+
+ switch (offset) {
+ case R_CR:
+ uart_ctrl_update(s);
+ break;
+ case R_MR:
+ uart_parameters_setup(s);
+ break;
+ }
+}
+
+static uint64_t uart_read(void *opaque, target_phys_addr_t offset,
+ unsigned size)
+{
+ UartState *s = (UartState *)opaque;
+ uint32_t c = 0;
+
+ offset >>= 2;
+ if (offset > R_MAX) {
+ return 0;
+ } else if (offset == R_TX_RX) {
+ uart_read_rx_fifo(s, &c);
+ return c;
+ }
+ return s->r[offset];
+}
+
+static const MemoryRegionOps uart_ops = {
+ .read = uart_read,
+ .write = uart_write,
+ .endianness = DEVICE_NATIVE_ENDIAN,
+};
+
+static void cadence_uart_reset(UartState *s)
+{
+ s->r[R_CR] = 0x00000128;
+ s->r[R_IMR] = 0;
+ s->r[R_CISR] = 0;
+ s->r[R_RTRIG] = 0x00000020;
+ s->r[R_BRGR] = 0x0000000F;
+ s->r[R_TTRIG] = 0x00000020;
+
+ uart_rx_reset(s);
+ uart_tx_reset(s);
+
+ s->rx_count = 0;
+ s->rx_wpos = 0;
+}
+
+static int cadence_uart_init(SysBusDevice *dev)
+{
+ UartState *s = FROM_SYSBUS(UartState, dev);
+
+ memory_region_init_io(&s->iomem, &uart_ops, s, "uart", 0x1000);
+ sysbus_init_mmio(dev, &s->iomem);
+ sysbus_init_irq(dev, &s->irq);
+
+ s->fifo_trigger_handle = qemu_new_timer_ns(vm_clock,
+ (QEMUTimerCB *)fifo_trigger_update, s);
+
+ s->tx_time_handle = qemu_new_timer_ns(vm_clock,
+ (QEMUTimerCB *)uart_tx_write, s);
+
+ s->char_tx_time = (get_ticks_per_sec() / 9600) * 10;
+
+ s->chr = qemu_char_get_next_serial();
+
+ cadence_uart_reset(s);
+
+ if (s->chr) {
+ qemu_chr_add_handlers(s->chr, uart_can_receive, uart_receive,
+ uart_event, s);
+ }
+
+ return 0;
+}
+
+static int cadence_uart_post_load(void *opaque, int version_id)
+{
+ UartState *s = opaque;
+
+ uart_parameters_setup(s);
+ uart_update_status(s);
+ return 0;
+}
+
+static const VMStateDescription vmstate_cadence_uart = {
+ .name = "cadence_uart",
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .minimum_version_id_old = 1,
+ .post_load = cadence_uart_post_load,
+ .fields = (VMStateField[]) {
+ VMSTATE_UINT32_ARRAY(r, UartState, R_MAX),
+ VMSTATE_UINT8_ARRAY(r_fifo, UartState, RX_FIFO_SIZE),
+ VMSTATE_UINT32(rx_count, UartState),
+ VMSTATE_UINT32(rx_wpos, UartState),
+ VMSTATE_TIMER(fifo_trigger_handle, UartState),
+ VMSTATE_TIMER(tx_time_handle, UartState),
+ VMSTATE_END_OF_LIST()
+ }
+};
+
+static void cadence_uart_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+ SysBusDeviceClass *sdc = SYS_BUS_DEVICE_CLASS(klass);
+
+ sdc->init = cadence_uart_init;
+ dc->vmsd = &vmstate_cadence_uart;
+}
+
+static TypeInfo cadence_uart_info = {
+ .name = "cadence_uart",
+ .parent = TYPE_SYS_BUS_DEVICE,
+ .instance_size = sizeof(UartState),
+ .class_init = cadence_uart_class_init,
+};
+
+static void cadence_uart_register_types(void)
+{
+ type_register_static(&cadence_uart_info);
+}
+
+type_init(cadence_uart_register_types)
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