xref: /openbmc/qemu/include/hw/misc/mos6522.h (revision d695918f)
1 /*
2  * QEMU MOS6522 VIA emulation
3  *
4  * Copyright (c) 2004-2007 Fabrice Bellard
5  * Copyright (c) 2007 Jocelyn Mayer
6  * Copyright (c) 2018 Mark Cave-Ayland
7  *
8  * Permission is hereby granted, free of charge, to any person obtaining a copy
9  * of this software and associated documentation files (the "Software"), to deal
10  * in the Software without restriction, including without limitation the rights
11  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
12  * copies of the Software, and to permit persons to whom the Software is
13  * furnished to do so, subject to the following conditions:
14  *
15  * The above copyright notice and this permission notice shall be included in
16  * all copies or substantial portions of the Software.
17  *
18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
21  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
22  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
23  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
24  * THE SOFTWARE.
25  */
26 
27 #ifndef MOS6522_H
28 #define MOS6522_H
29 
30 #include "exec/memory.h"
31 #include "hw/sysbus.h"
32 #include "hw/input/adb.h"
33 #include "qom/object.h"
34 
35 #define MOS6522_NUM_REGS 16
36 
37 /* Bits in ACR */
38 #define SR_CTRL            0x1c    /* Shift register control bits */
39 #define SR_EXT             0x0c    /* Shift on external clock */
40 #define SR_OUT             0x10    /* Shift out if 1 */
41 
42 /* Bits in IFR and IER */
43 #define IER_SET            0x80    /* set bits in IER */
44 #define IER_CLR            0       /* clear bits in IER */
45 
46 #define CA2_INT_BIT        0
47 #define CA1_INT_BIT        1
48 #define SR_INT_BIT         2       /* Shift register full/empty */
49 #define CB2_INT_BIT        3
50 #define CB1_INT_BIT        4
51 #define T2_INT_BIT         5       /* Timer 2 interrupt */
52 #define T1_INT_BIT         6       /* Timer 1 interrupt */
53 
54 #define CA2_INT            BIT(CA2_INT_BIT)
55 #define CA1_INT            BIT(CA1_INT_BIT)
56 #define SR_INT             BIT(SR_INT_BIT)
57 #define CB2_INT            BIT(CB2_INT_BIT)
58 #define CB1_INT            BIT(CB1_INT_BIT)
59 #define T2_INT             BIT(T2_INT_BIT)
60 #define T1_INT             BIT(T1_INT_BIT)
61 
62 #define VIA_NUM_INTS       5
63 
64 /* Bits in ACR */
65 #define T1MODE             0xc0    /* Timer 1 mode */
66 #define T1MODE_CONT        0x40    /*  continuous interrupts */
67 
68 /* Bits in PCR */
69 #define CB2_CTRL_MASK      0xe0
70 #define CB2_CTRL_SHIFT     5
71 #define CB1_CTRL_MASK      0x10
72 #define CB1_CTRL_SHIFT     4
73 #define CA2_CTRL_MASK      0x0e
74 #define CA2_CTRL_SHIFT     1
75 #define CA1_CTRL_MASK      0x1
76 #define CA1_CTRL_SHIFT     0
77 
78 #define C2_POS             0x2
79 #define C2_IND             0x1
80 
81 #define C1_POS             0x1
82 
83 /* VIA registers */
84 #define VIA_REG_B       0x00
85 #define VIA_REG_A       0x01
86 #define VIA_REG_DIRB    0x02
87 #define VIA_REG_DIRA    0x03
88 #define VIA_REG_T1CL    0x04
89 #define VIA_REG_T1CH    0x05
90 #define VIA_REG_T1LL    0x06
91 #define VIA_REG_T1LH    0x07
92 #define VIA_REG_T2CL    0x08
93 #define VIA_REG_T2CH    0x09
94 #define VIA_REG_SR      0x0a
95 #define VIA_REG_ACR     0x0b
96 #define VIA_REG_PCR     0x0c
97 #define VIA_REG_IFR     0x0d
98 #define VIA_REG_IER     0x0e
99 #define VIA_REG_ANH     0x0f
100 
101 /**
102  * MOS6522Timer:
103  * @counter_value: counter value at load time
104  */
105 typedef struct MOS6522Timer {
106     int index;
107     uint16_t latch;
108     uint16_t counter_value;
109     int64_t load_time;
110     int64_t next_irq_time;
111     uint64_t frequency;
112     QEMUTimer *timer;
113 } MOS6522Timer;
114 
115 /**
116  * MOS6522State:
117  * @b: B-side data
118  * @a: A-side data
119  * @dirb: B-side direction (1=output)
120  * @dira: A-side direction (1=output)
121  * @sr: Shift register
122  * @acr: Auxiliary control register
123  * @pcr: Peripheral control register
124  * @ifr: Interrupt flag register
125  * @ier: Interrupt enable register
126  * @anh: A-side data, no handshake
127  * @last_b: last value of B register
128  * @last_acr: last value of ACR register
129  */
130 struct MOS6522State {
131     /*< private >*/
132     SysBusDevice parent_obj;
133     /*< public >*/
134 
135     MemoryRegion mem;
136     /* VIA registers */
137     uint8_t b;
138     uint8_t a;
139     uint8_t dirb;
140     uint8_t dira;
141     uint8_t sr;
142     uint8_t acr;
143     uint8_t pcr;
144     uint8_t ifr;
145     uint8_t ier;
146 
147     MOS6522Timer timers[2];
148     uint64_t frequency;
149 
150     qemu_irq irq;
151     uint8_t last_irq_levels;
152 };
153 
154 #define TYPE_MOS6522 "mos6522"
155 OBJECT_DECLARE_TYPE(MOS6522State, MOS6522DeviceClass, MOS6522)
156 
157 struct MOS6522DeviceClass {
158     DeviceClass parent_class;
159 
160     DeviceReset parent_reset;
161     void (*portB_write)(MOS6522State *dev);
162     void (*portA_write)(MOS6522State *dev);
163     /* These are used to influence the CUDA MacOS timebase calibration */
164     uint64_t (*get_timer1_counter_value)(MOS6522State *dev, MOS6522Timer *ti);
165     uint64_t (*get_timer2_counter_value)(MOS6522State *dev, MOS6522Timer *ti);
166     uint64_t (*get_timer1_load_time)(MOS6522State *dev, MOS6522Timer *ti);
167     uint64_t (*get_timer2_load_time)(MOS6522State *dev, MOS6522Timer *ti);
168 };
169 
170 
171 extern const VMStateDescription vmstate_mos6522;
172 
173 uint64_t mos6522_read(void *opaque, hwaddr addr, unsigned size);
174 void mos6522_write(void *opaque, hwaddr addr, uint64_t val, unsigned size);
175 
176 void hmp_info_via(Monitor *mon, const QDict *qdict);
177 
178 #endif /* MOS6522_H */
179