xref: /openbmc/qemu/include/hw/char/ibex_uart.h (revision 1145188e)
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 "chardev/char-fe.h"
30 #include "qemu/timer.h"
31 
32 #define IBEX_UART_INTR_STATE   0x00
33     #define INTR_STATE_TX_WATERMARK (1 << 0)
34     #define INTR_STATE_RX_WATERMARK (1 << 1)
35     #define INTR_STATE_TX_EMPTY     (1 << 2)
36     #define INTR_STATE_RX_OVERFLOW  (1 << 3)
37 #define IBEX_UART_INTR_ENABLE  0x04
38 #define IBEX_UART_INTR_TEST    0x08
39 
40 #define IBEX_UART_CTRL         0x0c
41     #define UART_CTRL_TX_ENABLE     (1 << 0)
42     #define UART_CTRL_RX_ENABLE     (1 << 1)
43     #define UART_CTRL_NF            (1 << 2)
44     #define UART_CTRL_SLPBK         (1 << 4)
45     #define UART_CTRL_LLPBK         (1 << 5)
46     #define UART_CTRL_PARITY_EN     (1 << 6)
47     #define UART_CTRL_PARITY_ODD    (1 << 7)
48     #define UART_CTRL_RXBLVL        (3 << 8)
49     #define UART_CTRL_NCO           (0xFFFF << 16)
50 
51 #define IBEX_UART_STATUS       0x10
52     #define UART_STATUS_TXFULL  (1 << 0)
53     #define UART_STATUS_RXFULL  (1 << 1)
54     #define UART_STATUS_TXEMPTY (1 << 2)
55     #define UART_STATUS_RXIDLE  (1 << 4)
56     #define UART_STATUS_RXEMPTY (1 << 5)
57 
58 #define IBEX_UART_RDATA        0x14
59 #define IBEX_UART_WDATA        0x18
60 
61 #define IBEX_UART_FIFO_CTRL    0x1c
62     #define FIFO_CTRL_RXRST          (1 << 0)
63     #define FIFO_CTRL_TXRST          (1 << 1)
64     #define FIFO_CTRL_RXILVL         (7 << 2)
65     #define FIFO_CTRL_RXILVL_SHIFT   (2)
66     #define FIFO_CTRL_TXILVL         (3 << 5)
67     #define FIFO_CTRL_TXILVL_SHIFT   (5)
68 
69 #define IBEX_UART_FIFO_STATUS  0x20
70 #define IBEX_UART_OVRD         0x24
71 #define IBEX_UART_VAL          0x28
72 #define IBEX_UART_TIMEOUT_CTRL 0x2c
73 
74 #define IBEX_UART_TX_FIFO_SIZE 16
75 
76 #define TYPE_IBEX_UART "ibex-uart"
77 #define IBEX_UART(obj) \
78     OBJECT_CHECK(IbexUartState, (obj), TYPE_IBEX_UART)
79 
80 typedef struct {
81     /* <private> */
82     SysBusDevice parent_obj;
83 
84     /* <public> */
85     MemoryRegion mmio;
86 
87     uint8_t tx_fifo[IBEX_UART_TX_FIFO_SIZE];
88     uint32_t tx_level;
89 
90     QEMUTimer *fifo_trigger_handle;
91     uint64_t char_tx_time;
92 
93     uint32_t uart_intr_state;
94     uint32_t uart_intr_enable;
95     uint32_t uart_ctrl;
96     uint32_t uart_status;
97     uint32_t uart_rdata;
98     uint32_t uart_fifo_ctrl;
99     uint32_t uart_fifo_status;
100     uint32_t uart_ovrd;
101     uint32_t uart_val;
102     uint32_t uart_timeout_ctrl;
103 
104     CharBackend chr;
105     qemu_irq tx_watermark;
106     qemu_irq rx_watermark;
107     qemu_irq tx_empty;
108     qemu_irq rx_overflow;
109 } IbexUartState;
110 #endif /* HW_IBEX_UART_H */
111