/*
* QEMU GE IP-Octal 232 IndustryPack emulation
*
* Copyright (C) 2012 Igalia, S.L.
* Author: Alberto Garcia <berto@igalia.com>
*
* This code is licensed under the GNU GPL v2 or (at your option) any
* later version.
*/
#include "qemu/osdep.h"
#include "hw/ipack/ipack.h"
#include "qemu/bitops.h"
#include "chardev/char.h"
/* #define DEBUG_IPOCTAL */
#ifdef DEBUG_IPOCTAL
#define DPRINTF2(fmt, ...) \
do { fprintf(stderr, fmt, ## __VA_ARGS__); } while (0)
#else
#define DPRINTF2(fmt, ...) do { } while (0)
#endif
#define DPRINTF(fmt, ...) DPRINTF2("IP-Octal: " fmt, ## __VA_ARGS__)
#define RX_FIFO_SIZE 3
/* The IP-Octal has 8 channels (a-h)
divided into 4 blocks (A-D) */
#define N_CHANNELS 8
#define N_BLOCKS 4
#define REG_MRa 0x01
#define REG_MRb 0x11
#define REG_SRa 0x03
#define REG_SRb 0x13
#define REG_CSRa 0x03
#define REG_CSRb 0x13
#define REG_CRa 0x05
#define REG_CRb 0x15
#define REG_RHRa 0x07
#define REG_RHRb 0x17
#define REG_THRa 0x07
#define REG_THRb 0x17
#define REG_ACR 0x09
#define REG_ISR 0x0B
#define REG_IMR 0x0B
#define REG_OPCR 0x1B
#define CR_ENABLE_RX BIT(0)
#define CR_DISABLE_RX BIT(1)
#define CR_ENABLE_TX BIT(2)
#define CR_DISABLE_TX BIT(3)
#define CR_CMD(cr) ((cr) >> 4)
#define CR_NO_OP 0
#define CR_RESET_MR 1
#define CR_RESET_RX 2
#define CR_RESET_TX 3
#define CR_RESET_ERR 4
#define CR_RESET_BRKINT 5
#define CR_START_BRK 6
#define CR_STOP_BRK 7
#define CR_ASSERT_RTSN 8
#define CR_NEGATE_RTSN 9
#define CR_TIMEOUT_ON 10
#define CR_TIMEOUT_OFF 12
#define SR_RXRDY BIT(0)
#define SR_FFULL BIT(1)
#define SR_TXRDY BIT(2)
#define SR_TXEMT BIT(3)
#define SR_OVERRUN BIT(4)
#define SR_PARITY BIT(5)
#define SR_FRAMING BIT(6)
#define SR_BREAK BIT(7)
#define ISR_TXRDYA BIT(0)
#define ISR_RXRDYA BIT(1)
#define ISR_BREAKA BIT(2)
#define ISR_CNTRDY BIT(3)
#define ISR_TXRDYB BIT(4)
#define ISR_RXRDYB BIT(5)
#define ISR_BREAKB BIT(6)
#define ISR_MPICHG BIT(7)
#define ISR_TXRDY(CH) (((CH) & 1) ? BIT(4) : BIT(0))
#define ISR_RXRDY(CH) (((CH) & 1) ? BIT(5) : BIT(1))
#define ISR_BREAK(CH) (((CH) & 1) ? BIT(6) : BIT(2))
typedef struct IPOctalState IPOctalState;
typedef struct SCC2698Channel SCC2698Channel;
typedef struct SCC2698Block SCC2698Block;
struct SCC2698Channel {
IPOctalState *ipoctal;
CharBackend dev;
bool rx_enabled;
uint8_t mr[2];
uint8_t mr_idx;
uint8_t sr;
uint8_t rhr[RX_FIFO_SIZE];
uint8_t rhr_idx;
uint8_t rx_pending;
};
struct SCC2698Block {
uint8_t imr;
uint8_t isr;
};
struct IPOctalState {
IPackDevice parent_obj;
SCC2698Channel ch[N_CHANNELS];
SCC2698Block blk[N_BLOCKS];
uint8_t irq_vector;
};
#define TYPE_IPOCTAL "ipoctal232"
#define IPOCTAL(obj) \
OBJECT_CHECK(IPOctalState, (obj), TYPE_IPOCTAL)
static const VMStateDescription vmstate_scc2698_channel = {
.name = "scc2698_channel",
.version_id = 1,
.minimum_version_id = 1,
.fields = (VMStateField[]) {
VMSTATE_BOOL(rx_enabled, SCC2698Channel),
VMSTATE_UINT8_ARRAY(mr, SCC2698Channel, 2),
VMSTATE_UINT8(mr_idx, SCC2698Channel),
VMSTATE_UINT8(sr, SCC2698Channel),
VMSTATE_UINT8_ARRAY(rhr, SCC2698Channel, RX_FIFO_SIZE),
VMSTATE_UINT8(rhr_idx, SCC2698Channel),
VMSTATE_UINT8(rx_pending, SCC2698Channel),
VMSTATE_END_OF_LIST()
}
};
static const VMStateDescription vmstate_scc2698_block = {
.name = "scc2698_block",
.version_id = 1,
.minimum_version_id = 1,
.fields = (VMStateField[]) {
VMSTATE_UINT8(imr, SCC2698Block),
VMSTATE_UINT8(isr, SCC2698Block),
VMSTATE_END_OF_LIST()
}
};
static const VMStateDescription vmstate_ipoctal = {
.name = "ipoctal232",
.version_id = 1,
.minimum_version_id = 1,
.fields = (VMStateField[]) {
VMSTATE_IPACK_DEVICE(parent_obj, IPOctalState),
VMSTATE_STRUCT_ARRAY(ch, IPOctalState, N_CHANNELS, 1,
vmstate_scc2698_channel, SCC2698Channel),
VMSTATE_STRUCT_ARRAY(blk, IPOctalState, N_BLOCKS, 1,
vmstate_scc2698_block, SCC2698Block),
VMSTATE_UINT8(irq_vector, IPOctalState),
VMSTATE_END_OF_LIST()
}
};
/* data[10] is 0x0C, not 0x0B as the doc says */
static const uint8_t id_prom_data[] = {
0x49, 0x50, 0x41, 0x43, 0xF0, 0x22,
0xA1, 0x00, 0x00, 0x00, 0x0C, 0xCC
};
static void update_irq(IPOctalState *dev, unsigned block)
{
IPackDevice *idev = IPACK_DEVICE(dev);
/* Blocks A and B interrupt on INT0#, C and D on INT1#.
Thus, to get the status we have to check two blocks. */
SCC2698Block *blk0 = &dev->blk[block];
SCC2698Block *blk1 = &dev->blk[block^1];
unsigned intno = block / 2;
if ((blk0->isr & blk0->imr) || (blk1->isr & blk1->imr)) {
qemu_irq_raise(idev->irq[intno]);
} else {
qemu_irq_lower(idev->irq[intno]);
}
}
static void write_cr(IPOctalState *dev, unsigned channel, uint8_t val)
{
SCC2698Channel *ch = &dev->ch[channel];
SCC2698Block *blk = &dev->blk[channel / 2];
DPRINTF("Write CR%c %u: ", channel + 'a', val);
/* The lower 4 bits are used to enable and disable Tx and Rx */
if (val & CR_ENABLE_RX) {
DPRINTF2("Rx on, ");
ch->rx_enabled = true;
}
if (val & CR_DISABLE_RX) {
DPRINTF2("Rx off, ");
ch->rx_enabled = false;
}
if (val & CR_ENABLE_TX) {
DPRINTF2("Tx on, ");
ch->sr |= SR_TXRDY | SR_TXEMT;
blk->isr |= ISR_TXRDY(channel);
}
if (val & CR_DISABLE_TX) {
DPRINTF2("Tx off, ");
ch->sr &= ~(SR_TXRDY | SR_TXEMT);
blk->isr &= ~ISR_TXRDY(channel);
}
DPRINTF2("cmd: ");
/* The rest of the bits implement different commands */
switch (CR_CMD(val)) {
case CR_NO_OP:
DPRINTF2("none");
break;
case CR_RESET_MR:
DPRINTF2("reset MR");
ch->mr_idx = 0;
break;
case CR_RESET_RX:
DPRINTF2("reset Rx");
ch->rx_enabled = false;
ch->rx_pending = 0;
ch->sr &= ~SR_RXRDY;
blk->isr &= ~ISR_RXRDY(channel);
break;
case CR_RESET_TX:
DPRINTF2("reset Tx");
ch->sr &= ~(SR_TXRDY | SR_TXEMT);
blk->isr &= ~ISR_TXRDY(channel);
break;
case CR_RESET_ERR:
DPRINTF2("reset err");
ch->sr &= ~(SR_OVERRUN | SR_PARITY | SR_FRAMING | SR_BREAK);
break;
case CR_RESET_BRKINT:
DPRINTF2("reset brk ch int");
blk->isr &= ~(ISR_BREAKA | ISR_BREAKB);
break;
default:
DPRINTF2("unsupported 0x%x", CR_CMD(val));
}
DPRINTF2("\n");
}
static uint16_t io_read(IPackDevice *ip, uint8_t addr)
{
IPOctalState *dev = IPOCTAL(ip);
uint16_t ret = 0;
/* addr[7:6]: block (A-D)
addr[7:5]: channel (a-h)
addr[5:0]: register */
unsigned block = addr >> 5;
unsigned channel = addr >> 4;
/* Big endian, accessed using 8-bit bytes at odd locations */
unsigned offset = (addr & 0x1F) ^ 1;
SCC2698Channel *ch = &dev->ch[channel];
SCC2698Block *blk = &dev->blk[block];
uint8_t old_isr = blk->isr;
switch (offset) {
case REG_MRa:
case REG_MRb:
ret = ch->mr[ch->mr_idx];
DPRINTF("Read MR%u%c: 0x%x\n", ch->mr_idx + 1, channel + 'a', ret);
ch->mr_idx = 1;
break;
case REG_SRa:
case REG_SRb:
ret = ch->sr;
DPRINTF("Read SR%c: 0x%x\n", channel + 'a', ret);
break;
case REG_RHRa:
case REG_RHRb:
ret = ch->rhr[ch->rhr_idx];
if (ch->rx_pending > 0) {
ch->rx_pending--;
if (ch->rx_pending == 0) {
ch->sr &= ~SR_RXRDY;
blk->isr &= ~ISR_RXRDY(channel);
qemu_chr_fe_accept_input(&ch->dev);
} else {
ch->rhr_idx = (ch->rhr_idx + 1) % RX_FIFO_SIZE;
}
if (ch->sr & SR_BREAK) {
ch->sr &= ~SR_BREAK;
blk->isr |= ISR_BREAK(channel);
}
}
DPRINTF("Read RHR%c (0x%x)\n", channel + 'a', ret);
break;
case REG_ISR:
ret = blk->isr;
DPRINTF("Read ISR%c: 0x%x\n", block + 'A', ret);
break;
default:
DPRINTF("Read unknown/unsupported register 0x%02x\n", offset);
}
if (old_isr != blk->isr) {
update_irq(dev, block);
}
return ret;
}
static void io_write(IPackDevice *ip, uint8_t addr, uint16_t val)
{
IPOctalState *dev = IPOCTAL(ip);
unsigned reg = val & 0xFF;
/* addr[7:6]: block (A-D)
addr[7:5]: channel (a-h)
addr[5:0]: register */
unsigned block = addr >> 5;
unsigned channel = addr >> 4;
/* Big endian, accessed using 8-bit bytes at odd locations */
unsigned offset = (addr & 0x1F) ^ 1;
SCC2698Channel *ch = &dev->ch[channel];
SCC2698Block *blk = &dev->blk[block];
uint8_t old_isr = blk->isr;
uint8_t old_imr = blk->imr;
switch (offset) {
case REG_MRa:
case REG_MRb:
ch->mr[ch->mr_idx] = reg;
DPRINTF("Write MR%u%c 0x%x\n", ch->mr_idx + 1, channel + 'a', reg);
ch->mr_idx = 1;
break;
/* Not implemented */
case REG_CSRa:
case REG_CSRb:
DPRINTF("Write CSR%c: 0x%x\n", channel + 'a', reg);
break;
case REG_CRa:
case REG_CRb:
write_cr(dev, channel, reg);
break;
case REG_THRa:
case REG_THRb:
if (ch->sr & SR_TXRDY) {
uint8_t thr = reg;
DPRINTF("Write THR%c (0x%x)\n", channel + 'a', reg);
/* XXX this blocks entire thread. Rewrite to use
* qemu_chr_fe_write and background I/O callbacks */
qemu_chr_fe_write_all(&ch->dev, &thr, 1);
} else {
DPRINTF("Write THR%c (0x%x), Tx disabled\n", channel + 'a', reg);
}
break;
/* Not implemented */
case REG_ACR:
DPRINTF("Write ACR%c 0x%x\n", block + 'A', val);
break;
case REG_IMR:
DPRINTF("Write IMR%c 0x%x\n", block + 'A', val);
blk->imr = reg;
break;
/* Not implemented */
case REG_OPCR:
DPRINTF("Write OPCR%c 0x%x\n", block + 'A', val);
break;
default:
DPRINTF("Write unknown/unsupported register 0x%02x %u\n", offset, val);
}
if (old_isr != blk->isr || old_imr != blk->imr) {
update_irq(dev, block);
}
}
static uint16_t id_read(IPackDevice *ip, uint8_t addr)
{
uint16_t ret = 0;
unsigned pos = addr / 2; /* The ID PROM data is stored every other byte */
if (pos < ARRAY_SIZE(id_prom_data)) {
ret = id_prom_data[pos];
} else {
DPRINTF("Attempt to read unavailable PROM data at 0x%x\n", addr);
}
return ret;
}
static void id_write(IPackDevice *ip, uint8_t addr, uint16_t val)
{
IPOctalState *dev = IPOCTAL(ip);
if (addr == 1) {
DPRINTF("Write IRQ vector: %u\n", (unsigned) val);
dev->irq_vector = val; /* Undocumented, but the hw works like that */
} else {
DPRINTF("Attempt to write 0x%x to 0x%x\n", val, addr);
}
}
static uint16_t int_read(IPackDevice *ip, uint8_t addr)
{
IPOctalState *dev = IPOCTAL(ip);
/* Read address 0 to ACK INT0# and address 2 to ACK INT1# */
if (addr != 0 && addr != 2) {
DPRINTF("Attempt to read from 0x%x\n", addr);
return 0;
} else {
/* Update interrupts if necessary */
update_irq(dev, addr);
return dev->irq_vector;
}
}
static void int_write(IPackDevice *ip, uint8_t addr, uint16_t val)
{
DPRINTF("Attempt to write 0x%x to 0x%x\n", val, addr);
}
static uint16_t mem_read16(IPackDevice *ip, uint32_t addr)
{
DPRINTF("Attempt to read from 0x%x\n", addr);
return 0;
}
static void mem_write16(IPackDevice *ip, uint32_t addr, uint16_t val)
{
DPRINTF("Attempt to write 0x%x to 0x%x\n", val, addr);
}
static uint8_t mem_read8(IPackDevice *ip, uint32_t addr)
{
DPRINTF("Attempt to read from 0x%x\n", addr);
return 0;
}
static void mem_write8(IPackDevice *ip, uint32_t addr, uint8_t val)
{
IPOctalState *dev = IPOCTAL(ip);
if (addr == 1) {
DPRINTF("Write IRQ vector: %u\n", (unsigned) val);
dev->irq_vector = val;
} else {
DPRINTF("Attempt to write 0x%x to 0x%x\n", val, addr);
}
}
static int hostdev_can_receive(void *opaque)
{
SCC2698Channel *ch = opaque;
int available_bytes = RX_FIFO_SIZE - ch->rx_pending;
return ch->rx_enabled ? available_bytes : 0;
}
static void hostdev_receive(void *opaque, const uint8_t *buf, int size)
{
SCC2698Channel *ch = opaque;
IPOctalState *dev = ch->ipoctal;
unsigned pos = ch->rhr_idx + ch->rx_pending;
int i;
assert(size + ch->rx_pending <= RX_FIFO_SIZE);
/* Copy data to the RxFIFO */
for (i = 0; i < size; i++) {
pos %= RX_FIFO_SIZE;
ch->rhr[pos++] = buf[i];
}
ch->rx_pending += size;
/* If the RxFIFO was empty raise an interrupt */
if (!(ch->sr & SR_RXRDY)) {
unsigned block, channel = 0;
/* Find channel number to update the ISR register */
while (&dev->ch[channel] != ch) {
channel++;
}
block = channel / 2;
dev->blk[block].isr |= ISR_RXRDY(channel);
ch->sr |= SR_RXRDY;
update_irq(dev, block);
}
}
static void hostdev_event(void *opaque, int event)
{
SCC2698Channel *ch = opaque;
switch (event) {
case CHR_EVENT_OPENED:
DPRINTF("Device %s opened\n", ch->dev->label);
break;
case CHR_EVENT_BREAK: {
uint8_t zero = 0;
DPRINTF("Device %s received break\n", ch->dev->label);
if (!(ch->sr & SR_BREAK)) {
IPOctalState *dev = ch->ipoctal;
unsigned block, channel = 0;
while (&dev->ch[channel] != ch) {
channel++;
}
block = channel / 2;
ch->sr |= SR_BREAK;
dev->blk[block].isr |= ISR_BREAK(channel);
}
/* Put a zero character in the buffer */
hostdev_receive(ch, &zero, 1);
}
break;
default:
DPRINTF("Device %s received event %d\n", ch->dev->label, event);
}
}
static void ipoctal_realize(DeviceState *dev, Error **errp)
{
IPOctalState *s = IPOCTAL(dev);
unsigned i;
for (i = 0; i < N_CHANNELS; i++) {
SCC2698Channel *ch = &s->ch[i];
ch->ipoctal = s;
/* Redirect IP-Octal channels to host character devices */
if (qemu_chr_fe_get_driver(&ch->dev)) {
qemu_chr_fe_set_handlers(&ch->dev, hostdev_can_receive,
hostdev_receive, hostdev_event,
ch, NULL, true);
DPRINTF("Redirecting channel %u to %s\n", i, ch->dev->label);
} else {
DPRINTF("Could not redirect channel %u, no chardev set\n", i);
}
}
}
static Property ipoctal_properties[] = {
DEFINE_PROP_CHR("chardev0", IPOctalState, ch[0].dev),
DEFINE_PROP_CHR("chardev1", IPOctalState, ch[1].dev),
DEFINE_PROP_CHR("chardev2", IPOctalState, ch[2].dev),
DEFINE_PROP_CHR("chardev3", IPOctalState, ch[3].dev),
DEFINE_PROP_CHR("chardev4", IPOctalState, ch[4].dev),
DEFINE_PROP_CHR("chardev5", IPOctalState, ch[5].dev),
DEFINE_PROP_CHR("chardev6", IPOctalState, ch[6].dev),
DEFINE_PROP_CHR("chardev7", IPOctalState, ch[7].dev),
DEFINE_PROP_END_OF_LIST(),
};
static void ipoctal_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
IPackDeviceClass *ic = IPACK_DEVICE_CLASS(klass);
ic->realize = ipoctal_realize;
ic->io_read = io_read;
ic->io_write = io_write;
ic->id_read = id_read;
ic->id_write = id_write;
ic->int_read = int_read;
ic->int_write = int_write;
ic->mem_read16 = mem_read16;
ic->mem_write16 = mem_write16;
ic->mem_read8 = mem_read8;
ic->mem_write8 = mem_write8;
set_bit(DEVICE_CATEGORY_INPUT, dc->categories);
dc->desc = "GE IP-Octal 232 8-channel RS-232 IndustryPack";
dc->props = ipoctal_properties;
dc->vmsd = &vmstate_ipoctal;
}
static const TypeInfo ipoctal_info = {
.name = TYPE_IPOCTAL,
.parent = TYPE_IPACK_DEVICE,
.instance_size = sizeof(IPOctalState),
.class_init = ipoctal_class_init,
};
static void ipoctal_register_types(void)
{
type_register_static(&ipoctal_info);
}
type_init(ipoctal_register_types)
