diff options
author | Michael Walle <michael@walle.cc> | 2011-02-17 23:45:11 +0100 |
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committer | Edgar E. Iglesias <edgar.iglesias@gmail.com> | 2011-03-07 13:42:36 +0100 |
commit | 770ae5713af30e42492581fd53000a1b4a92a3c7 (patch) | |
tree | 3f66778402ea05fdc1a854035ff90f46b0a3956c /hw/lm32_uart.c | |
parent | ea7924dcc4000643ad767fa106a15acb9f8e055b (diff) |
lm32: uart model
This patch add support for the LatticeMico32 UART.
Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@gmail.com>
Diffstat (limited to 'hw/lm32_uart.c')
-rw-r--r-- | hw/lm32_uart.c | 288 |
1 files changed, 288 insertions, 0 deletions
diff --git a/hw/lm32_uart.c b/hw/lm32_uart.c new file mode 100644 index 0000000000..e225087b99 --- /dev/null +++ b/hw/lm32_uart.c @@ -0,0 +1,288 @@ +/* + * QEMU model of the LatticeMico32 UART block. + * + * Copyright (c) 2010 Michael Walle <michael@walle.cc> + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This library 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 + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, see <http://www.gnu.org/licenses/>. + * + * + * Specification available at: + * http://www.latticesemi.com/documents/mico32uart.pdf + */ + + +#include "hw.h" +#include "sysbus.h" +#include "trace.h" +#include "qemu-char.h" +#include "qemu-error.h" + +enum { + R_RXTX = 0, + R_IER, + R_IIR, + R_LCR, + R_MCR, + R_LSR, + R_MSR, + R_DIV, + R_MAX +}; + +enum { + IER_RBRI = (1<<0), + IER_THRI = (1<<1), + IER_RLSI = (1<<2), + IER_MSI = (1<<3), +}; + +enum { + IIR_STAT = (1<<0), + IIR_ID0 = (1<<1), + IIR_ID1 = (1<<2), +}; + +enum { + LCR_WLS0 = (1<<0), + LCR_WLS1 = (1<<1), + LCR_STB = (1<<2), + LCR_PEN = (1<<3), + LCR_EPS = (1<<4), + LCR_SP = (1<<5), + LCR_SB = (1<<6), +}; + +enum { + MCR_DTR = (1<<0), + MCR_RTS = (1<<1), +}; + +enum { + LSR_DR = (1<<0), + LSR_OE = (1<<1), + LSR_PE = (1<<2), + LSR_FE = (1<<3), + LSR_BI = (1<<4), + LSR_THRE = (1<<5), + LSR_TEMT = (1<<6), +}; + +enum { + MSR_DCTS = (1<<0), + MSR_DDSR = (1<<1), + MSR_TERI = (1<<2), + MSR_DDCD = (1<<3), + MSR_CTS = (1<<4), + MSR_DSR = (1<<5), + MSR_RI = (1<<6), + MSR_DCD = (1<<7), +}; + +struct LM32UartState { + SysBusDevice busdev; + CharDriverState *chr; + qemu_irq irq; + + uint32_t regs[R_MAX]; +}; +typedef struct LM32UartState LM32UartState; + +static void uart_update_irq(LM32UartState *s) +{ + unsigned int irq; + + if ((s->regs[R_LSR] & (LSR_OE | LSR_PE | LSR_FE | LSR_BI)) + && (s->regs[R_IER] & IER_RLSI)) { + irq = 1; + s->regs[R_IIR] = IIR_ID1 | IIR_ID0; + } else if ((s->regs[R_LSR] & LSR_DR) && (s->regs[R_IER] & IER_RBRI)) { + irq = 1; + s->regs[R_IIR] = IIR_ID1; + } else if ((s->regs[R_LSR] & LSR_THRE) && (s->regs[R_IER] & IER_THRI)) { + irq = 1; + s->regs[R_IIR] = IIR_ID0; + } else if ((s->regs[R_MSR] & 0x0f) && (s->regs[R_IER] & IER_MSI)) { + irq = 1; + s->regs[R_IIR] = 0; + } else { + irq = 0; + s->regs[R_IIR] = IIR_STAT; + } + + trace_lm32_uart_irq_state(irq); + qemu_set_irq(s->irq, irq); +} + +static uint32_t uart_read(void *opaque, target_phys_addr_t addr) +{ + LM32UartState *s = opaque; + uint32_t r = 0; + + addr >>= 2; + switch (addr) { + case R_RXTX: + r = s->regs[R_RXTX]; + s->regs[R_LSR] &= ~LSR_DR; + uart_update_irq(s); + break; + case R_IIR: + case R_LSR: + case R_MSR: + r = s->regs[addr]; + break; + case R_IER: + case R_LCR: + case R_MCR: + case R_DIV: + error_report("lm32_uart: read access to write only register 0x" + TARGET_FMT_plx, addr << 2); + break; + default: + error_report("lm32_uart: read access to unkown register 0x" + TARGET_FMT_plx, addr << 2); + break; + } + + trace_lm32_uart_memory_read(addr << 2, r); + return r; +} + +static void uart_write(void *opaque, target_phys_addr_t addr, uint32_t value) +{ + LM32UartState *s = opaque; + unsigned char ch = value; + + trace_lm32_uart_memory_write(addr, value); + + addr >>= 2; + switch (addr) { + case R_RXTX: + if (s->chr) { + qemu_chr_write(s->chr, &ch, 1); + } + break; + case R_IER: + case R_LCR: + case R_MCR: + case R_DIV: + s->regs[addr] = value; + break; + case R_IIR: + case R_LSR: + case R_MSR: + error_report("lm32_uart: write access to read only register 0x" + TARGET_FMT_plx, addr << 2); + break; + default: + error_report("lm32_uart: write access to unkown register 0x" + TARGET_FMT_plx, addr << 2); + break; + } + uart_update_irq(s); +} + +static CPUReadMemoryFunc * const uart_read_fn[] = { + NULL, + NULL, + &uart_read, +}; + +static CPUWriteMemoryFunc * const uart_write_fn[] = { + NULL, + NULL, + &uart_write, +}; + +static void uart_rx(void *opaque, const uint8_t *buf, int size) +{ + LM32UartState *s = opaque; + + if (s->regs[R_LSR] & LSR_DR) { + s->regs[R_LSR] |= LSR_OE; + } + + s->regs[R_LSR] |= LSR_DR; + s->regs[R_RXTX] = *buf; + + uart_update_irq(s); +} + +static int uart_can_rx(void *opaque) +{ + LM32UartState *s = opaque; + + return !(s->regs[R_LSR] & LSR_DR); +} + +static void uart_event(void *opaque, int event) +{ +} + +static void uart_reset(DeviceState *d) +{ + LM32UartState *s = container_of(d, LM32UartState, busdev.qdev); + int i; + + for (i = 0; i < R_MAX; i++) { + s->regs[i] = 0; + } + + /* defaults */ + s->regs[R_LSR] = LSR_THRE | LSR_TEMT; +} + +static int lm32_uart_init(SysBusDevice *dev) +{ + LM32UartState *s = FROM_SYSBUS(typeof(*s), dev); + int uart_regs; + + sysbus_init_irq(dev, &s->irq); + + uart_regs = cpu_register_io_memory(uart_read_fn, uart_write_fn, s, + DEVICE_NATIVE_ENDIAN); + sysbus_init_mmio(dev, R_MAX * 4, uart_regs); + + s->chr = qdev_init_chardev(&dev->qdev); + if (s->chr) { + qemu_chr_add_handlers(s->chr, uart_can_rx, uart_rx, uart_event, s); + } + + return 0; +} + +static const VMStateDescription vmstate_lm32_uart = { + .name = "lm32-uart", + .version_id = 1, + .minimum_version_id = 1, + .minimum_version_id_old = 1, + .fields = (VMStateField[]) { + VMSTATE_UINT32_ARRAY(regs, LM32UartState, R_MAX), + VMSTATE_END_OF_LIST() + } +}; + +static SysBusDeviceInfo lm32_uart_info = { + .init = lm32_uart_init, + .qdev.name = "lm32-uart", + .qdev.size = sizeof(LM32UartState), + .qdev.vmsd = &vmstate_lm32_uart, + .qdev.reset = uart_reset, +}; + +static void lm32_uart_register(void) +{ + sysbus_register_withprop(&lm32_uart_info); +} + +device_init(lm32_uart_register) |