/*
* PPC4xx I2C controller emulation
*
* Copyright (c) 2007 Jocelyn Mayer
* Copyright (c) 2012 François Revol
* Copyright (c) 2016 BALATON Zoltan
*
* 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.
*/
#include "qemu/osdep.h"
#include "qapi/error.h"
#include "qemu-common.h"
#include "qemu/log.h"
#include "cpu.h"
#include "hw/hw.h"
#include "hw/i2c/ppc4xx_i2c.h"
#define PPC4xx_I2C_MEM_SIZE 0x12
#define IIC_CNTL_PT (1 << 0)
#define IIC_CNTL_READ (1 << 1)
#define IIC_CNTL_CHT (1 << 2)
#define IIC_CNTL_RPST (1 << 3)
#define IIC_STS_PT (1 << 0)
#define IIC_STS_ERR (1 << 2)
#define IIC_STS_MDBS (1 << 5)
#define IIC_EXTSTS_XFRA (1 << 0)
#define IIC_XTCNTLSS_SRST (1 << 0)
static void ppc4xx_i2c_reset(DeviceState *s)
{
PPC4xxI2CState *i2c = PPC4xx_I2C(s);
/* FIXME: Should also reset bus?
*if (s->address != ADDR_RESET) {
* i2c_end_transfer(s->bus);
*}
*/
i2c->mdata = 0;
i2c->lmadr = 0;
i2c->hmadr = 0;
i2c->cntl = 0;
i2c->mdcntl = 0;
i2c->sts = 0;
i2c->extsts = 0x8f;
i2c->sdata = 0;
i2c->lsadr = 0;
i2c->hsadr = 0;
i2c->clkdiv = 0;
i2c->intrmsk = 0;
i2c->xfrcnt = 0;
i2c->xtcntlss = 0;
i2c->directcntl = 0x0f;
i2c->intr = 0;
}
static inline bool ppc4xx_i2c_is_master(PPC4xxI2CState *i2c)
{
return true;
}
static uint64_t ppc4xx_i2c_readb(void *opaque, hwaddr addr, unsigned int size)
{
PPC4xxI2CState *i2c = PPC4xx_I2C(opaque);
uint64_t ret;
switch (addr) {
case 0x00:
ret = i2c->mdata;
if (ppc4xx_i2c_is_master(i2c)) {
ret = 0xff;
if (!(i2c->sts & IIC_STS_MDBS)) {
qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: Trying to read "
"without starting transfer\n",
TYPE_PPC4xx_I2C, __func__);
} else {
int pending = (i2c->cntl >> 4) & 3;
/* get the next byte */
int byte = i2c_recv(i2c->bus);
if (byte < 0) {
qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: read failed "
"for device 0x%02x\n", TYPE_PPC4xx_I2C,
__func__, i2c->lmadr);
ret = 0xff;
} else {
ret = byte;
/* Raise interrupt if enabled */
/*ppc4xx_i2c_raise_interrupt(i2c)*/;
}
if (!pending) {
i2c->sts &= ~IIC_STS_MDBS;
/*i2c_end_transfer(i2c->bus);*/
/*} else if (i2c->cntl & (IIC_CNTL_RPST | IIC_CNTL_CHT)) {*/
} else if (pending) {
/* current smbus implementation doesn't like
multibyte xfer repeated start */
i2c_end_transfer(i2c->bus);
if (i2c_start_transfer(i2c->bus, i2c->lmadr >> 1, 1)) {
/* if non zero is returned, the adress is not valid */
i2c->sts &= ~IIC_STS_PT;
i2c->sts |= IIC_STS_ERR;
i2c->extsts |= IIC_EXTSTS_XFRA;
} else {
/*i2c->sts |= IIC_STS_PT;*/
i2c->sts |= IIC_STS_MDBS;
i2c->sts &= ~IIC_STS_ERR;
i2c->extsts = 0;
}
}
pending--;
i2c->cntl = (i2c->cntl & 0xcf) | (pending << 4);
}
} else {
qemu_log_mask(LOG_UNIMP, "[%s]%s: slave mode not implemented\n",
TYPE_PPC4xx_I2C, __func__);
}
break;
case 0x02:
ret = i2c->sdata;
break;
case 0x04:
ret = i2c->lmadr;
break;
case 0x05:
ret = i2c->hmadr;
break;
case 0x06:
ret = i2c->cntl;
break;
case 0x07:
ret = i2c->mdcntl;
break;
case 0x08:
ret = i2c->sts;
break;
case 0x09:
ret = i2c->extsts;
break;
case 0x0A:
ret = i2c->lsadr;
break;
case 0x0B:
ret = i2c->hsadr;
break;
case 0x0C:
ret = i2c->clkdiv;
break;
case 0x0D:
ret = i2c->intrmsk;
break;
case 0x0E:
ret = i2c->xfrcnt;
break;
case 0x0F:
ret = i2c->xtcntlss;
break;
case 0x10:
ret = i2c->directcntl;
break;
case 0x11:
ret = i2c->intr;
break;
default:
qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: Bad address at offset 0x%"
HWADDR_PRIx "\n", TYPE_PPC4xx_I2C, __func__, addr);
ret = 0;
break;
}
return ret;
}
static void ppc4xx_i2c_writeb(void *opaque, hwaddr addr, uint64_t value,
unsigned int size)
{
PPC4xxI2CState *i2c = opaque;
switch (addr) {
case 0x00:
i2c->mdata = value;
if (!i2c_bus_busy(i2c->bus)) {
/* assume we start a write transfer */
if (i2c_start_transfer(i2c->bus, i2c->lmadr >> 1, 0)) {
/* if non zero is returned, the adress is not valid */
i2c->sts &= ~IIC_STS_PT;
i2c->sts |= IIC_STS_ERR;
i2c->extsts |= IIC_EXTSTS_XFRA;
} else {
i2c->sts |= IIC_STS_PT;
i2c->sts &= ~IIC_STS_ERR;
i2c->extsts = 0;
}
}
if (i2c_bus_busy(i2c->bus)) {
if (i2c_send(i2c->bus, i2c->mdata)) {
/* if the target return non zero then end the transfer */
i2c->sts &= ~IIC_STS_PT;
i2c->sts |= IIC_STS_ERR;
i2c->extsts |= IIC_EXTSTS_XFRA;
i2c_end_transfer(i2c->bus);
}
}
break;
case 0x02:
i2c->sdata = value;
break;
case 0x04:
i2c->lmadr = value;
if (i2c_bus_busy(i2c->bus)) {
i2c_end_transfer(i2c->bus);
}
break;
case 0x05:
i2c->hmadr = value;
break;
case 0x06:
i2c->cntl = value;
if (i2c->cntl & IIC_CNTL_PT) {
if (i2c->cntl & IIC_CNTL_READ) {
if (i2c_bus_busy(i2c->bus)) {
/* end previous transfer */
i2c->sts &= ~IIC_STS_PT;
i2c_end_transfer(i2c->bus);
}
if (i2c_start_transfer(i2c->bus, i2c->lmadr >> 1, 1)) {
/* if non zero is returned, the adress is not valid */
i2c->sts &= ~IIC_STS_PT;
i2c->sts |= IIC_STS_ERR;
i2c->extsts |= IIC_EXTSTS_XFRA;
} else {
/*i2c->sts |= IIC_STS_PT;*/
i2c->sts |= IIC_STS_MDBS;
i2c->sts &= ~IIC_STS_ERR;
i2c->extsts = 0;
}
} else {
/* we actually already did the write transfer... */
i2c->sts &= ~IIC_STS_PT;
}
}
break;
case 0x07:
i2c->mdcntl = value & 0xDF;
break;
case 0x08:
i2c->sts &= ~(value & 0x0A);
break;
case 0x09:
i2c->extsts &= ~(value & 0x8F);
break;
case 0x0A:
i2c->lsadr = value;
/*i2c_set_slave_address(i2c->bus, i2c->lsadr);*/
break;
case 0x0B:
i2c->hsadr = value;
break;
case 0x0C:
i2c->clkdiv = value;
break;
case 0x0D:
i2c->intrmsk = value;
break;
case 0x0E:
i2c->xfrcnt = value & 0x77;
break;
case 0x0F:
if (value & IIC_XTCNTLSS_SRST) {
/* Is it actually a full reset? U-Boot sets some regs before */
ppc4xx_i2c_reset(DEVICE(i2c));
break;
}
i2c->xtcntlss = value;
break;
case 0x10:
i2c->directcntl = value & 0x7;
break;
case 0x11:
i2c->intr = value;
break;
default:
qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: Bad address at offset 0x%"
HWADDR_PRIx "\n", TYPE_PPC4xx_I2C, __func__, addr);
break;
}
}
static const MemoryRegionOps ppc4xx_i2c_ops = {
.read = ppc4xx_i2c_readb,
.write = ppc4xx_i2c_writeb,
.valid.min_access_size = 1,
.valid.max_access_size = 4,
.impl.min_access_size = 1,
.impl.max_access_size = 1,
.endianness = DEVICE_NATIVE_ENDIAN,
};
static void ppc4xx_i2c_init(Object *o)
{
PPC4xxI2CState *s = PPC4xx_I2C(o);
memory_region_init_io(&s->iomem, OBJECT(s), &ppc4xx_i2c_ops, s,
TYPE_PPC4xx_I2C, PPC4xx_I2C_MEM_SIZE);
sysbus_init_mmio(SYS_BUS_DEVICE(s), &s->iomem);
sysbus_init_irq(SYS_BUS_DEVICE(s), &s->irq);
s->bus = i2c_init_bus(DEVICE(s), "i2c");
}
static void ppc4xx_i2c_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
dc->reset = ppc4xx_i2c_reset;
}
static const TypeInfo ppc4xx_i2c_type_info = {
.name = TYPE_PPC4xx_I2C,
.parent = TYPE_SYS_BUS_DEVICE,
.instance_size = sizeof(PPC4xxI2CState),
.instance_init = ppc4xx_i2c_init,
.class_init = ppc4xx_i2c_class_init,
};
static void ppc4xx_i2c_register_types(void)
{
type_register_static(&ppc4xx_i2c_type_info);
}
type_init(ppc4xx_i2c_register_types)