| /* |
| * 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 "hw/sysbus.h" |
| #include "sysemu/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 |
| /* somewhat awkwardly, TTRIG is misaligned between SR and ISR */ |
| #define UART_SR_TTRIG 0x00002000 |
| #define UART_INTR_TTRIG 0x00000400 |
| /* 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_INTR_TOVR 0x00001000 |
| |
| #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) |
| |
| #define TYPE_CADENCE_UART "cadence_uart" |
| #define CADENCE_UART(obj) OBJECT_CHECK(UartState, (obj), TYPE_CADENCE_UART) |
| |
| typedef struct { |
| /*< private >*/ |
| SysBusDevice parent_obj; |
| /*< public >*/ |
| |
| MemoryRegion iomem; |
| uint32_t r[R_MAX]; |
| uint8_t rx_fifo[RX_FIFO_SIZE]; |
| uint8_t tx_fifo[TX_FIFO_SIZE]; |
| uint32_t rx_wpos; |
| uint32_t rx_count; |
| uint32_t tx_count; |
| uint64_t char_tx_time; |
| CharDriverState *chr; |
| qemu_irq irq; |
| QEMUTimer *fifo_trigger_handle; |
| } UartState; |
| |
| static void uart_update_status(UartState *s) |
| { |
| s->r[R_SR] = 0; |
| |
| s->r[R_SR] |= s->rx_count == RX_FIFO_SIZE ? UART_SR_INTR_RFUL : 0; |
| s->r[R_SR] |= !s->rx_count ? UART_SR_INTR_REMPTY : 0; |
| s->r[R_SR] |= s->rx_count >= s->r[R_RTRIG] ? UART_SR_INTR_RTRIG : 0; |
| |
| s->r[R_SR] |= s->tx_count == TX_FIFO_SIZE ? UART_SR_INTR_TFUL : 0; |
| s->r[R_SR] |= !s->tx_count ? UART_SR_INTR_TEMPTY : 0; |
| s->r[R_SR] |= s->tx_count >= s->r[R_TTRIG] ? UART_SR_TTRIG : 0; |
| |
| s->r[R_CISR] |= s->r[R_SR] & UART_SR_TO_CISR_MASK; |
| s->r[R_CISR] |= s->r[R_SR] & UART_SR_TTRIG ? UART_INTR_TTRIG : 0; |
| 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_rx_reset(UartState *s) |
| { |
| s->rx_wpos = 0; |
| s->rx_count = 0; |
| if (s->chr) { |
| qemu_chr_accept_input(s->chr); |
| } |
| } |
| |
| static void uart_tx_reset(UartState *s) |
| { |
| s->tx_count = 0; |
| } |
| |
| 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; |
| int ret = MAX(RX_FIFO_SIZE, TX_FIFO_SIZE); |
| uint32_t ch_mode = s->r[R_MR] & UART_MR_CHMODE; |
| |
| if (ch_mode == NORMAL_MODE || ch_mode == ECHO_MODE) { |
| ret = MIN(ret, RX_FIFO_SIZE - s->rx_count); |
| } |
| if (ch_mode == REMOTE_LOOPBACK || ch_mode == ECHO_MODE) { |
| ret = MIN(ret, TX_FIFO_SIZE - s->tx_count); |
| } |
| return ret; |
| } |
| |
| 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_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_clock_get_ns(QEMU_CLOCK_VIRTUAL); |
| int i; |
| |
| if ((s->r[R_CR] & UART_CR_RX_DIS) || !(s->r[R_CR] & UART_CR_RX_EN)) { |
| return; |
| } |
| |
| if (s->rx_count == RX_FIFO_SIZE) { |
| s->r[R_CISR] |= UART_INTR_ROVR; |
| } else { |
| for (i = 0; i < size; i++) { |
| s->rx_fifo[s->rx_wpos] = buf[i]; |
| s->rx_wpos = (s->rx_wpos + 1) % RX_FIFO_SIZE; |
| s->rx_count++; |
| } |
| timer_mod(s->fifo_trigger_handle, new_rx_time + |
| (s->char_tx_time * 4)); |
| } |
| uart_update_status(s); |
| } |
| |
| static gboolean cadence_uart_xmit(GIOChannel *chan, GIOCondition cond, |
| void *opaque) |
| { |
| UartState *s = opaque; |
| int ret; |
| |
| /* instant drain the fifo when there's no back-end */ |
| if (!s->chr) { |
| s->tx_count = 0; |
| } |
| |
| if (!s->tx_count) { |
| return FALSE; |
| } |
| |
| ret = qemu_chr_fe_write(s->chr, s->tx_fifo, s->tx_count); |
| s->tx_count -= ret; |
| memmove(s->tx_fifo, s->tx_fifo + ret, s->tx_count); |
| |
| if (s->tx_count) { |
| int r = qemu_chr_fe_add_watch(s->chr, G_IO_OUT, cadence_uart_xmit, s); |
| assert(r); |
| } |
| |
| uart_update_status(s); |
| return FALSE; |
| } |
| |
| 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; |
| } |
| |
| if (size > TX_FIFO_SIZE - s->tx_count) { |
| size = TX_FIFO_SIZE - s->tx_count; |
| /* |
| * This can only be a guest error via a bad tx fifo register push, |
| * as can_receive() should stop remote loop and echo modes ever getting |
| * us to here. |
| */ |
| qemu_log_mask(LOG_GUEST_ERROR, "cadence_uart: TxFIFO overflow"); |
| s->r[R_CISR] |= UART_INTR_ROVR; |
| } |
| |
| memcpy(s->tx_fifo + s->tx_count, buf, size); |
| s->tx_count += size; |
| |
| cadence_uart_xmit(NULL, G_IO_OUT, s); |
| } |
| |
| 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; |
| } |
| |
| if (s->rx_count) { |
| uint32_t rx_rpos = |
| (RX_FIFO_SIZE + s->rx_wpos - s->rx_count) % RX_FIFO_SIZE; |
| *c = s->rx_fifo[rx_rpos]; |
| s->rx_count--; |
| |
| qemu_chr_accept_input(s->chr); |
| } else { |
| *c = 0; |
| } |
| |
| uart_update_status(s); |
| } |
| |
| static void uart_write(void *opaque, hwaddr offset, |
| uint64_t value, unsigned size) |
| { |
| UartState *s = (UartState *)opaque; |
| |
| DB_PRINT(" offset:%x data:%08x\n", (unsigned)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; |
| } |
| uart_update_status(s); |
| } |
| |
| static uint64_t uart_read(void *opaque, hwaddr offset, |
| unsigned size) |
| { |
| UartState *s = (UartState *)opaque; |
| uint32_t c = 0; |
| |
| offset >>= 2; |
| if (offset >= R_MAX) { |
| c = 0; |
| } else if (offset == R_TX_RX) { |
| uart_read_rx_fifo(s, &c); |
| } else { |
| c = s->r[offset]; |
| } |
| |
| DB_PRINT(" offset:%x data:%08x\n", (unsigned)(offset << 2), (unsigned)c); |
| return c; |
| } |
| |
| static const MemoryRegionOps uart_ops = { |
| .read = uart_read, |
| .write = uart_write, |
| .endianness = DEVICE_NATIVE_ENDIAN, |
| }; |
| |
| static void cadence_uart_reset(DeviceState *dev) |
| { |
| UartState *s = CADENCE_UART(dev); |
| |
| 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); |
| |
| uart_update_status(s); |
| } |
| |
| static int cadence_uart_init(SysBusDevice *dev) |
| { |
| UartState *s = CADENCE_UART(dev); |
| |
| memory_region_init_io(&s->iomem, OBJECT(s), &uart_ops, s, "uart", 0x1000); |
| sysbus_init_mmio(dev, &s->iomem); |
| sysbus_init_irq(dev, &s->irq); |
| |
| s->fifo_trigger_handle = timer_new_ns(QEMU_CLOCK_VIRTUAL, |
| (QEMUTimerCB *)fifo_trigger_update, s); |
| |
| s->char_tx_time = (get_ticks_per_sec() / 9600) * 10; |
| |
| s->chr = qemu_char_get_next_serial(); |
| |
| 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 = 2, |
| .minimum_version_id = 2, |
| .minimum_version_id_old = 2, |
| .post_load = cadence_uart_post_load, |
| .fields = (VMStateField[]) { |
| VMSTATE_UINT32_ARRAY(r, UartState, R_MAX), |
| VMSTATE_UINT8_ARRAY(rx_fifo, UartState, RX_FIFO_SIZE), |
| VMSTATE_UINT8_ARRAY(tx_fifo, UartState, RX_FIFO_SIZE), |
| VMSTATE_UINT32(rx_count, UartState), |
| VMSTATE_UINT32(tx_count, UartState), |
| VMSTATE_UINT32(rx_wpos, UartState), |
| VMSTATE_TIMER(fifo_trigger_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; |
| dc->reset = cadence_uart_reset; |
| } |
| |
| static const TypeInfo cadence_uart_info = { |
| .name = TYPE_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) |