From 883de16b464554e195fe7e20daaa9525cfeaf3a2 Mon Sep 17 00:00:00 2001 From: Michael Walle Date: Mon, 7 Mar 2011 23:32:41 +0100 Subject: [PATCH] lm32: add Milkymist UART support This patch adds support for Milkymist's simple UART. Signed-off-by: Michael Walle Signed-off-by: Edgar E. Iglesias --- Makefile.target | 1 + hw/milkymist-uart.c | 180 ++++++++++++++++++++++++++++++++++++++++++++ trace-events | 6 ++ 3 files changed, 187 insertions(+) create mode 100644 hw/milkymist-uart.c diff --git a/Makefile.target b/Makefile.target index 6581519064..c009117e47 100644 --- a/Makefile.target +++ b/Makefile.target @@ -275,6 +275,7 @@ obj-lm32-y += milkymist-pfpu.o obj-lm32-y += milkymist-softusb.o obj-lm32-y += milkymist-sysctl.o obj-lm32-$(CONFIG_OPENGL) += milkymist-tmu2.o +obj-lm32-y += milkymist-uart.o obj-mips-y = mips_r4k.o mips_jazz.o mips_malta.o mips_mipssim.o obj-mips-y += mips_addr.o mips_timer.o mips_int.o diff --git a/hw/milkymist-uart.c b/hw/milkymist-uart.c new file mode 100644 index 0000000000..56c90da0b6 --- /dev/null +++ b/hw/milkymist-uart.c @@ -0,0 +1,180 @@ +/* + * QEMU model of the Milkymist UART block. + * + * Copyright (c) 2010 Michael Walle + * + * 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 . + * + * + * Specification available at: + * http://www.milkymist.org/socdoc/uart.pdf + */ + +#include "hw.h" +#include "sysbus.h" +#include "trace.h" +#include "qemu-char.h" +#include "qemu-error.h" + +enum { + R_RXTX = 0, + R_DIV, + R_MAX +}; + +struct MilkymistUartState { + SysBusDevice busdev; + CharDriverState *chr; + qemu_irq rx_irq; + qemu_irq tx_irq; + + uint32_t regs[R_MAX]; +}; +typedef struct MilkymistUartState MilkymistUartState; + +static uint32_t uart_read(void *opaque, target_phys_addr_t addr) +{ + MilkymistUartState *s = opaque; + uint32_t r = 0; + + addr >>= 2; + switch (addr) { + case R_RXTX: + case R_DIV: + r = s->regs[addr]; + break; + + default: + error_report("milkymist_uart: read access to unknown register 0x" + TARGET_FMT_plx, addr << 2); + break; + } + + trace_milkymist_uart_memory_read(addr << 2, r); + + return r; +} + +static void uart_write(void *opaque, target_phys_addr_t addr, uint32_t value) +{ + MilkymistUartState *s = opaque; + unsigned char ch = value; + + trace_milkymist_uart_memory_write(addr, value); + + addr >>= 2; + switch (addr) { + case R_RXTX: + if (s->chr) { + qemu_chr_write(s->chr, &ch, 1); + } + trace_milkymist_uart_pulse_irq_tx(); + qemu_irq_pulse(s->tx_irq); + break; + case R_DIV: + s->regs[addr] = value; + break; + + default: + error_report("milkymist_uart: write access to unknown register 0x" + TARGET_FMT_plx, addr << 2); + break; + } +} + +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) +{ + MilkymistUartState *s = opaque; + + s->regs[R_RXTX] = *buf; + trace_milkymist_uart_pulse_irq_rx(); + qemu_irq_pulse(s->rx_irq); +} + +static int uart_can_rx(void *opaque) +{ + return 1; +} + +static void uart_event(void *opaque, int event) +{ +} + +static void milkymist_uart_reset(DeviceState *d) +{ + MilkymistUartState *s = container_of(d, MilkymistUartState, busdev.qdev); + int i; + + for (i = 0; i < R_MAX; i++) { + s->regs[i] = 0; + } +} + +static int milkymist_uart_init(SysBusDevice *dev) +{ + MilkymistUartState *s = FROM_SYSBUS(typeof(*s), dev); + int uart_regs; + + sysbus_init_irq(dev, &s->rx_irq); + sysbus_init_irq(dev, &s->tx_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_milkymist_uart = { + .name = "milkymist-uart", + .version_id = 1, + .minimum_version_id = 1, + .minimum_version_id_old = 1, + .fields = (VMStateField[]) { + VMSTATE_UINT32_ARRAY(regs, MilkymistUartState, R_MAX), + VMSTATE_END_OF_LIST() + } +}; + +static SysBusDeviceInfo milkymist_uart_info = { + .init = milkymist_uart_init, + .qdev.name = "milkymist-uart", + .qdev.size = sizeof(MilkymistUartState), + .qdev.vmsd = &vmstate_milkymist_uart, + .qdev.reset = milkymist_uart_reset, +}; + +static void milkymist_uart_register(void) +{ + sysbus_register_withprop(&milkymist_uart_info); +} + +device_init(milkymist_uart_register) diff --git a/trace-events b/trace-events index 3a88adfdad..55f3de532a 100644 --- a/trace-events +++ b/trace-events @@ -349,3 +349,9 @@ disable milkymist_tmu2_memory_read(uint32_t addr, uint32_t value) "addr %08x val disable milkymist_tmu2_memory_write(uint32_t addr, uint32_t value) "addr %08x value %08x" disable milkymist_tmu2_start(void) "Start TMU" disable milkymist_tmu2_pulse_irq(void) "Pulse IRQ" + +# hw/milkymist-uart.c +disable milkymist_uart_memory_read(uint32_t addr, uint32_t value) "addr %08x value %08x" +disable milkymist_uart_memory_write(uint32_t addr, uint32_t value) "addr %08x value %08x" +disable milkymist_uart_pulse_irq_rx(void) "Pulse IRQ RX" +disable milkymist_uart_pulse_irq_tx(void) "Pulse IRQ TX"