xref: /openbmc/qemu/include/hw/char/cmsdk-apb-uart.h (revision 59a3a1c0)
1 /*
2  * ARM CMSDK APB UART emulation
3  *
4  * Copyright (c) 2017 Linaro Limited
5  * Written by Peter Maydell
6  *
7  *  This program is free software; you can redistribute it and/or modify
8  *  it under the terms of the GNU General Public License version 2 or
9  *  (at your option) any later version.
10  */
11 
12 #ifndef CMSDK_APB_UART_H
13 #define CMSDK_APB_UART_H
14 
15 #include "hw/qdev-properties.h"
16 #include "hw/sysbus.h"
17 #include "chardev/char-fe.h"
18 
19 #define TYPE_CMSDK_APB_UART "cmsdk-apb-uart"
20 #define CMSDK_APB_UART(obj) OBJECT_CHECK(CMSDKAPBUART, (obj), \
21                                          TYPE_CMSDK_APB_UART)
22 
23 typedef struct {
24     /*< private >*/
25     SysBusDevice parent_obj;
26 
27     /*< public >*/
28     MemoryRegion iomem;
29     CharBackend chr;
30     qemu_irq txint;
31     qemu_irq rxint;
32     qemu_irq txovrint;
33     qemu_irq rxovrint;
34     qemu_irq uartint;
35     guint watch_tag;
36     uint32_t pclk_frq;
37 
38     uint32_t state;
39     uint32_t ctrl;
40     uint32_t intstatus;
41     uint32_t bauddiv;
42     /* This UART has no FIFO, only a 1-character buffer for each of Tx and Rx */
43     uint8_t txbuf;
44     uint8_t rxbuf;
45 } CMSDKAPBUART;
46 
47 /**
48  * cmsdk_apb_uart_create - convenience function to create TYPE_CMSDK_APB_UART
49  * @addr: location in system memory to map registers
50  * @chr: Chardev backend to connect UART to, or NULL if no backend
51  * @pclk_frq: frequency in Hz of the PCLK clock (used for calculating baud rate)
52  */
53 static inline DeviceState *cmsdk_apb_uart_create(hwaddr addr,
54                                                  qemu_irq txint,
55                                                  qemu_irq rxint,
56                                                  qemu_irq txovrint,
57                                                  qemu_irq rxovrint,
58                                                  qemu_irq uartint,
59                                                  Chardev *chr,
60                                                  uint32_t pclk_frq)
61 {
62     DeviceState *dev;
63     SysBusDevice *s;
64 
65     dev = qdev_create(NULL, TYPE_CMSDK_APB_UART);
66     s = SYS_BUS_DEVICE(dev);
67     qdev_prop_set_chr(dev, "chardev", chr);
68     qdev_prop_set_uint32(dev, "pclk-frq", pclk_frq);
69     qdev_init_nofail(dev);
70     sysbus_mmio_map(s, 0, addr);
71     sysbus_connect_irq(s, 0, txint);
72     sysbus_connect_irq(s, 1, rxint);
73     sysbus_connect_irq(s, 2, txovrint);
74     sysbus_connect_irq(s, 3, rxovrint);
75     sysbus_connect_irq(s, 4, uartint);
76     return dev;
77 }
78 
79 #endif
80