/*
* QEMU MOS6522 VIA emulation
*
* Copyright (c) 2004-2007 Fabrice Bellard
* Copyright (c) 2007 Jocelyn Mayer
* Copyright (c) 2018 Mark Cave-Ayland
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#ifndef MOS6522_H
#define MOS6522_H
#include "exec/memory.h"
#include "hw/sysbus.h"
#include "hw/input/adb.h"
#include "qom/object.h"
/* Bits in ACR */
#define SR_CTRL 0x1c /* Shift register control bits */
#define SR_EXT 0x0c /* Shift on external clock */
#define SR_OUT 0x10 /* Shift out if 1 */
/* Bits in IFR and IER */
#define IER_SET 0x80 /* set bits in IER */
#define IER_CLR 0 /* clear bits in IER */
#define CA2_INT 0x01
#define CA1_INT 0x02
#define SR_INT 0x04 /* Shift register full/empty */
#define CB2_INT 0x08
#define CB1_INT 0x10
#define T2_INT 0x20 /* Timer 2 interrupt */
#define T1_INT 0x40 /* Timer 1 interrupt */
/* Bits in ACR */
#define T1MODE 0xc0 /* Timer 1 mode */
#define T1MODE_CONT 0x40 /* continuous interrupts */
/* VIA registers */
#define VIA_REG_B 0x00
#define VIA_REG_A 0x01
#define VIA_REG_DIRB 0x02
#define VIA_REG_DIRA 0x03
#define VIA_REG_T1CL 0x04
#define VIA_REG_T1CH 0x05
#define VIA_REG_T1LL 0x06
#define VIA_REG_T1LH 0x07
#define VIA_REG_T2CL 0x08
#define VIA_REG_T2CH 0x09
#define VIA_REG_SR 0x0a
#define VIA_REG_ACR 0x0b
#define VIA_REG_PCR 0x0c
#define VIA_REG_IFR 0x0d
#define VIA_REG_IER 0x0e
#define VIA_REG_ANH 0x0f
/**
* MOS6522Timer:
* @counter_value: counter value at load time
*/
typedef struct MOS6522Timer {
int index;
uint16_t latch;
uint16_t counter_value;
int64_t load_time;
int64_t next_irq_time;
uint64_t frequency;
QEMUTimer *timer;
} MOS6522Timer;
/**
* MOS6522State:
* @b: B-side data
* @a: A-side data
* @dirb: B-side direction (1=output)
* @dira: A-side direction (1=output)
* @sr: Shift register
* @acr: Auxiliary control register
* @pcr: Peripheral control register
* @ifr: Interrupt flag register
* @ier: Interrupt enable register
* @anh: A-side data, no handshake
* @last_b: last value of B register
* @last_acr: last value of ACR register
*/
struct MOS6522State {
/*< private >*/
SysBusDevice parent_obj;
/*< public >*/
MemoryRegion mem;
/* VIA registers */
uint8_t b;
uint8_t a;
uint8_t dirb;
uint8_t dira;
uint8_t sr;
uint8_t acr;
uint8_t pcr;
uint8_t ifr;
uint8_t ier;
MOS6522Timer timers[2];
uint64_t frequency;
qemu_irq irq;
};
#define TYPE_MOS6522 "mos6522"
OBJECT_DECLARE_TYPE(MOS6522State, MOS6522DeviceClass, MOS6522)
struct MOS6522DeviceClass {
DeviceClass parent_class;
DeviceReset parent_reset;
void (*set_sr_int)(MOS6522State *dev);
void (*portB_write)(MOS6522State *dev);
void (*portA_write)(MOS6522State *dev);
void (*update_irq)(MOS6522State *dev);
/* These are used to influence the CUDA MacOS timebase calibration */
uint64_t (*get_timer1_counter_value)(MOS6522State *dev, MOS6522Timer *ti);
uint64_t (*get_timer2_counter_value)(MOS6522State *dev, MOS6522Timer *ti);
uint64_t (*get_timer1_load_time)(MOS6522State *dev, MOS6522Timer *ti);
uint64_t (*get_timer2_load_time)(MOS6522State *dev, MOS6522Timer *ti);
};
extern const VMStateDescription vmstate_mos6522;
uint64_t mos6522_read(void *opaque, hwaddr addr, unsigned size);
void mos6522_write(void *opaque, hwaddr addr, uint64_t val, unsigned size);
#endif /* MOS6522_H */
