xemu/include/hw/char/cmsdk-apb-uart.h
Peter Maydell 775df84e48 hw/char/cmsdk-apb-uart.c: Implement CMSDK APB UART
Implement a model of the simple "APB UART" provided in
the Cortex-M System Design Kit (CMSDK).

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1500029487-14822-3-git-send-email-peter.maydell@linaro.org
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
2017-07-17 13:36:08 +01:00

79 lines
2.3 KiB
C

/*
* ARM CMSDK APB UART emulation
*
* Copyright (c) 2017 Linaro Limited
* Written by Peter Maydell
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 or
* (at your option) any later version.
*/
#ifndef CMSDK_APB_UART_H
#define CMSDK_APB_UART_H
#include "hw/sysbus.h"
#include "chardev/char-fe.h"
#define TYPE_CMSDK_APB_UART "cmsdk-apb-uart"
#define CMSDK_APB_UART(obj) OBJECT_CHECK(CMSDKAPBUART, (obj), \
TYPE_CMSDK_APB_UART)
typedef struct {
/*< private >*/
SysBusDevice parent_obj;
/*< public >*/
MemoryRegion iomem;
CharBackend chr;
qemu_irq txint;
qemu_irq rxint;
qemu_irq txovrint;
qemu_irq rxovrint;
qemu_irq uartint;
guint watch_tag;
uint32_t pclk_frq;
uint32_t state;
uint32_t ctrl;
uint32_t intstatus;
uint32_t bauddiv;
/* This UART has no FIFO, only a 1-character buffer for each of Tx and Rx */
uint8_t txbuf;
uint8_t rxbuf;
} CMSDKAPBUART;
/**
* cmsdk_apb_uart_create - convenience function to create TYPE_CMSDK_APB_UART
* @addr: location in system memory to map registers
* @chr: Chardev backend to connect UART to, or NULL if no backend
* @pclk_frq: frequency in Hz of the PCLK clock (used for calculating baud rate)
*/
static inline DeviceState *cmsdk_apb_uart_create(hwaddr addr,
qemu_irq txint,
qemu_irq rxint,
qemu_irq txovrint,
qemu_irq rxovrint,
qemu_irq uartint,
Chardev *chr,
uint32_t pclk_frq)
{
DeviceState *dev;
SysBusDevice *s;
dev = qdev_create(NULL, TYPE_CMSDK_APB_UART);
s = SYS_BUS_DEVICE(dev);
qdev_prop_set_chr(dev, "chardev", chr);
qdev_prop_set_uint32(dev, "pclk-frq", pclk_frq);
qdev_init_nofail(dev);
sysbus_mmio_map(s, 0, addr);
sysbus_connect_irq(s, 0, txint);
sysbus_connect_irq(s, 1, rxint);
sysbus_connect_irq(s, 2, txovrint);
sysbus_connect_irq(s, 3, rxovrint);
sysbus_connect_irq(s, 4, uartint);
return dev;
}
#endif