xref: /openbmc/qemu/include/hw/char/ibex_uart.h (revision 954a6c4f)
1 /*
2  * QEMU lowRISC Ibex UART device
3  *
4  * Copyright (c) 2020 Western Digital
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to deal
8  * in the Software without restriction, including without limitation the rights
9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10  * copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22  * THE SOFTWARE.
23  */
24 
25 #ifndef HW_IBEX_UART_H
26 #define HW_IBEX_UART_H
27 
28 #include "hw/sysbus.h"
29 #include "hw/registerfields.h"
30 #include "chardev/char-fe.h"
31 #include "qemu/timer.h"
32 #include "qom/object.h"
33 
34 #define IBEX_UART_TX_FIFO_SIZE 16
35 #define IBEX_UART_CLOCK 50000000 /* 50MHz clock */
36 
37 #define TYPE_IBEX_UART "ibex-uart"
38 OBJECT_DECLARE_SIMPLE_TYPE(IbexUartState, IBEX_UART)
39 
40 struct IbexUartState {
41     /* <private> */
42     SysBusDevice parent_obj;
43 
44     /* <public> */
45     MemoryRegion mmio;
46 
47     uint8_t tx_fifo[IBEX_UART_TX_FIFO_SIZE];
48     uint32_t tx_level;
49 
50     uint32_t rx_level;
51 
52     QEMUTimer *fifo_trigger_handle;
53     uint64_t char_tx_time;
54 
55     uint32_t uart_intr_state;
56     uint32_t uart_intr_enable;
57     uint32_t uart_ctrl;
58     uint32_t uart_status;
59     uint32_t uart_rdata;
60     uint32_t uart_fifo_ctrl;
61     uint32_t uart_fifo_status;
62     uint32_t uart_ovrd;
63     uint32_t uart_val;
64     uint32_t uart_timeout_ctrl;
65 
66     Clock *f_clk;
67 
68     CharBackend chr;
69     qemu_irq tx_watermark;
70     qemu_irq rx_watermark;
71     qemu_irq tx_empty;
72     qemu_irq rx_overflow;
73 };
74 #endif /* HW_IBEX_UART_H */
75