blob: eec5047ce83f842108b53a6e2bd9869a81f14ac1 [file] [log] [blame]
/*
* QEMU PowerPC PowerNV Processor I2C model
*
* Copyright (c) 2019-2023, IBM Corporation.
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
#include "qemu/osdep.h"
#include "qemu/module.h"
#include "qemu/log.h"
#include "sysemu/reset.h"
#include "hw/irq.h"
#include "hw/qdev-properties.h"
#include "hw/ppc/pnv.h"
#include "hw/ppc/pnv_chip.h"
#include "hw/ppc/pnv_i2c.h"
#include "hw/ppc/pnv_xscom.h"
#include "hw/ppc/fdt.h"
#include <libfdt.h>
#include "hw/i2c/pnv_i2c_regs.h"
static I2CBus *pnv_i2c_get_bus(PnvI2C *i2c)
{
uint8_t port = GETFIELD(I2C_MODE_PORT_NUM, i2c->regs[I2C_MODE_REG]);
if (port >= i2c->num_busses) {
qemu_log_mask(LOG_GUEST_ERROR, "I2C: invalid bus number %d/%d\n", port,
i2c->num_busses);
return NULL;
}
return i2c->busses[port];
}
static void pnv_i2c_update_irq(PnvI2C *i2c)
{
I2CBus *bus = pnv_i2c_get_bus(i2c);
bool recv = !!(i2c->regs[I2C_CMD_REG] & I2C_CMD_READ_NOT_WRITE);
uint16_t front_end = GETFIELD(I2C_RESIDUAL_FRONT_END,
i2c->regs[I2C_RESIDUAL_LEN_REG]);
uint16_t back_end = GETFIELD(I2C_RESIDUAL_BACK_END,
i2c->regs[I2C_RESIDUAL_LEN_REG]);
uint8_t fifo_count = GETFIELD(I2C_STAT_FIFO_ENTRY_COUNT,
i2c->regs[I2C_STAT_REG]);
uint8_t fifo_free = PNV_I2C_FIFO_SIZE - fifo_count;
if (!bus) {
qemu_log_mask(LOG_GUEST_ERROR, "I2C: invalid port\n");
return;
}
if (i2c_bus_busy(bus)) {
i2c->regs[I2C_STAT_REG] &= ~I2C_STAT_DATA_REQ;
if (recv) {
if (fifo_count >=
GETFIELD(I2C_WATERMARK_HIGH, i2c->regs[I2C_WATERMARK_REG])) {
i2c->regs[I2C_EXTD_STAT_REG] |= I2C_EXTD_STAT_HIGH_WATER;
} else {
i2c->regs[I2C_EXTD_STAT_REG] &= ~I2C_EXTD_STAT_HIGH_WATER;
}
if (((i2c->regs[I2C_EXTD_STAT_REG] & I2C_EXTD_STAT_HIGH_WATER) &&
fifo_count != 0) || front_end == 0) {
i2c->regs[I2C_STAT_REG] |= I2C_STAT_DATA_REQ;
}
} else {
if (fifo_count <=
GETFIELD(I2C_WATERMARK_LOW, i2c->regs[I2C_WATERMARK_REG])) {
i2c->regs[I2C_EXTD_STAT_REG] |= I2C_EXTD_STAT_LOW_WATER;
} else {
i2c->regs[I2C_EXTD_STAT_REG] &= ~I2C_EXTD_STAT_LOW_WATER;
}
if (back_end > 0 &&
(fifo_free >= back_end ||
(i2c->regs[I2C_EXTD_STAT_REG] & I2C_EXTD_STAT_LOW_WATER))) {
i2c->regs[I2C_STAT_REG] |= I2C_STAT_DATA_REQ;
}
}
if (back_end == 0 && front_end == 0) {
i2c->regs[I2C_STAT_REG] &= ~I2C_STAT_DATA_REQ;
i2c->regs[I2C_STAT_REG] |= I2C_STAT_CMD_COMP;
if (i2c->regs[I2C_CMD_REG] & I2C_CMD_WITH_STOP) {
i2c_end_transfer(bus);
i2c->regs[I2C_EXTD_STAT_REG] &=
~(I2C_EXTD_STAT_I2C_BUSY | I2C_EXTD_STAT_SELF_BUSY);
}
} else {
i2c->regs[I2C_STAT_REG] &= ~I2C_STAT_CMD_COMP;
}
}
/*
* Status and interrupt registers have nearly the same layout.
*/
i2c->regs[I2C_INTR_RAW_COND_REG] = i2c->regs[I2C_STAT_REG] >> 16;
i2c->regs[I2C_INTR_COND_REG] =
i2c->regs[I2C_INTR_RAW_COND_REG] & i2c->regs[I2C_INTR_MASK_REG];
qemu_set_irq(i2c->psi_irq, i2c->regs[I2C_INTR_COND_REG] != 0);
}
static void pnv_i2c_fifo_update_count(PnvI2C *i2c)
{
uint64_t stat = i2c->regs[I2C_STAT_REG];
i2c->regs[I2C_STAT_REG] = SETFIELD(I2C_STAT_FIFO_ENTRY_COUNT, stat,
fifo8_num_used(&i2c->fifo));
}
static void pnv_i2c_frontend_update(PnvI2C *i2c)
{
uint64_t residual_end = i2c->regs[I2C_RESIDUAL_LEN_REG];
uint16_t front_end = GETFIELD(I2C_RESIDUAL_FRONT_END, residual_end);
i2c->regs[I2C_RESIDUAL_LEN_REG] =
SETFIELD(I2C_RESIDUAL_FRONT_END, residual_end, front_end - 1);
}
static void pnv_i2c_fifo_flush(PnvI2C *i2c)
{
I2CBus *bus = pnv_i2c_get_bus(i2c);
uint8_t data;
int ret;
if (!bus) {
qemu_log_mask(LOG_GUEST_ERROR, "I2C: invalid port\n");
return;
}
if (!i2c_bus_busy(bus)) {
return;
}
if (i2c->regs[I2C_CMD_REG] & I2C_CMD_READ_NOT_WRITE) {
if (fifo8_is_full(&i2c->fifo)) {
return;
}
data = i2c_recv(bus);
fifo8_push(&i2c->fifo, data);
} else {
if (fifo8_is_empty(&i2c->fifo)) {
return;
}
data = fifo8_pop(&i2c->fifo);
ret = i2c_send(bus, data);
if (ret) {
i2c->regs[I2C_STAT_REG] |= I2C_STAT_NACK_RCVD_ERR;
i2c_end_transfer(bus);
}
}
pnv_i2c_fifo_update_count(i2c);
pnv_i2c_frontend_update(i2c);
}
static void pnv_i2c_handle_cmd(PnvI2C *i2c, uint64_t val)
{
I2CBus *bus = pnv_i2c_get_bus(i2c);
uint8_t addr = GETFIELD(I2C_CMD_DEV_ADDR, val);
int recv = !!(val & I2C_CMD_READ_NOT_WRITE);
uint32_t len_bytes = GETFIELD(I2C_CMD_LEN_BYTES, val);
if (!(val & I2C_CMD_WITH_START) && !(val & I2C_CMD_WITH_ADDR) &&
!(val & I2C_CMD_WITH_STOP) && !len_bytes) {
i2c->regs[I2C_STAT_REG] |= I2C_STAT_INVALID_CMD;
qemu_log_mask(LOG_GUEST_ERROR, "I2C: invalid command 0x%"PRIx64"\n",
val);
return;
}
if (!(i2c->regs[I2C_STAT_REG] & I2C_STAT_CMD_COMP)) {
i2c->regs[I2C_STAT_REG] |= I2C_STAT_INVALID_CMD;
qemu_log_mask(LOG_GUEST_ERROR, "I2C: command in progress\n");
return;
}
if (!bus) {
qemu_log_mask(LOG_GUEST_ERROR, "I2C: invalid port\n");
return;
}
i2c->regs[I2C_RESIDUAL_LEN_REG] =
SETFIELD(I2C_RESIDUAL_FRONT_END, 0ull, len_bytes) |
SETFIELD(I2C_RESIDUAL_BACK_END, 0ull, len_bytes);
if (val & I2C_CMD_WITH_START) {
if (i2c_start_transfer(bus, addr, recv)) {
i2c->regs[I2C_STAT_REG] |= I2C_STAT_NACK_RCVD_ERR;
} else {
i2c->regs[I2C_EXTD_STAT_REG] |=
(I2C_EXTD_STAT_I2C_BUSY | I2C_EXTD_STAT_SELF_BUSY);
pnv_i2c_fifo_flush(i2c);
}
}
}
static void pnv_i2c_backend_update(PnvI2C *i2c)
{
uint64_t residual_end = i2c->regs[I2C_RESIDUAL_LEN_REG];
uint16_t back_end = GETFIELD(I2C_RESIDUAL_BACK_END, residual_end);
if (!back_end) {
i2c->regs[I2C_STAT_REG] |= I2C_STAT_BKEND_ACCESS_ERR;
return;
}
i2c->regs[I2C_RESIDUAL_LEN_REG] =
SETFIELD(I2C_RESIDUAL_BACK_END, residual_end, back_end - 1);
}
static void pnv_i2c_fifo_in(PnvI2C *i2c)
{
uint8_t data = GETFIELD(I2C_FIFO, i2c->regs[I2C_FIFO_REG]);
I2CBus *bus = pnv_i2c_get_bus(i2c);
if (!bus) {
qemu_log_mask(LOG_GUEST_ERROR, "I2C: invalid port\n");
return;
}
if (!i2c_bus_busy(bus)) {
i2c->regs[I2C_STAT_REG] |= I2C_STAT_INVALID_CMD;
qemu_log_mask(LOG_GUEST_ERROR, "I2C: no command in progress\n");
return;
}
if (i2c->regs[I2C_CMD_REG] & I2C_CMD_READ_NOT_WRITE) {
i2c->regs[I2C_STAT_REG] |= I2C_STAT_INVALID_CMD;
qemu_log_mask(LOG_GUEST_ERROR, "I2C: read command in progress\n");
return;
}
if (fifo8_is_full(&i2c->fifo)) {
if (!(i2c->regs[I2C_MODE_REG] & I2C_MODE_PACING_ALLOW)) {
i2c->regs[I2C_STAT_REG] |= I2C_STAT_BKEND_OVERRUN_ERR;
}
return;
}
fifo8_push(&i2c->fifo, data);
pnv_i2c_fifo_update_count(i2c);
pnv_i2c_backend_update(i2c);
pnv_i2c_fifo_flush(i2c);
}
static void pnv_i2c_fifo_out(PnvI2C *i2c)
{
uint8_t data;
I2CBus *bus = pnv_i2c_get_bus(i2c);
if (!bus) {
qemu_log_mask(LOG_GUEST_ERROR, "I2C: invalid port\n");
return;
}
if (!i2c_bus_busy(bus)) {
i2c->regs[I2C_STAT_REG] |= I2C_STAT_INVALID_CMD;
qemu_log_mask(LOG_GUEST_ERROR, "I2C: no command in progress\n");
return;
}
if (!(i2c->regs[I2C_CMD_REG] & I2C_CMD_READ_NOT_WRITE)) {
i2c->regs[I2C_STAT_REG] |= I2C_STAT_INVALID_CMD;
qemu_log_mask(LOG_GUEST_ERROR, "I2C: write command in progress\n");
return;
}
if (fifo8_is_empty(&i2c->fifo)) {
if (!(i2c->regs[I2C_MODE_REG] & I2C_MODE_PACING_ALLOW)) {
i2c->regs[I2C_STAT_REG] |= I2C_STAT_BKEND_OVERRUN_ERR;
}
return;
}
data = fifo8_pop(&i2c->fifo);
i2c->regs[I2C_FIFO_REG] = SETFIELD(I2C_FIFO, 0ull, data);
pnv_i2c_fifo_update_count(i2c);
pnv_i2c_backend_update(i2c);
}
static uint64_t pnv_i2c_xscom_read(void *opaque, hwaddr addr,
unsigned size)
{
PnvI2C *i2c = PNV_I2C(opaque);
uint32_t offset = addr >> 3;
uint64_t val = -1;
int i;
switch (offset) {
case I2C_STAT_REG:
val = i2c->regs[offset];
break;
case I2C_FIFO_REG:
pnv_i2c_fifo_out(i2c);
val = i2c->regs[offset];
break;
case I2C_PORT_BUSY_REG: /* compute busy bit for each port */
val = 0;
for (i = 0; i < i2c->num_busses; i++) {
val |= (uint64_t)i2c_bus_busy(i2c->busses[i]) << i;
}
break;
case I2C_CMD_REG:
case I2C_MODE_REG:
case I2C_WATERMARK_REG:
case I2C_INTR_MASK_REG:
case I2C_INTR_RAW_COND_REG:
case I2C_INTR_COND_REG:
case I2C_EXTD_STAT_REG:
case I2C_RESIDUAL_LEN_REG:
val = i2c->regs[offset];
break;
default:
i2c->regs[I2C_STAT_REG] |= I2C_STAT_INVALID_CMD;
qemu_log_mask(LOG_GUEST_ERROR, "I2C: read at register: 0x%"
HWADDR_PRIx "\n", addr >> 3);
}
pnv_i2c_update_irq(i2c);
return val;
}
static void pnv_i2c_reset(void *dev)
{
PnvI2C *i2c = PNV_I2C(dev);
memset(i2c->regs, 0, sizeof(i2c->regs));
i2c->regs[I2C_STAT_REG] =
SETFIELD(I2C_STAT_UPPER_THRS, 0ull, i2c->num_busses - 1) |
I2C_STAT_CMD_COMP | I2C_STAT_SCL_INPUT_LEVEL |
I2C_STAT_SDA_INPUT_LEVEL;
i2c->regs[I2C_EXTD_STAT_REG] =
SETFIELD(I2C_EXTD_STAT_FIFO_SIZE, 0ull, PNV_I2C_FIFO_SIZE) |
SETFIELD(I2C_EXTD_STAT_I2C_VERSION, 0ull, 23); /* last version */
fifo8_reset(&i2c->fifo);
}
static void pnv_i2c_xscom_write(void *opaque, hwaddr addr,
uint64_t val, unsigned size)
{
PnvI2C *i2c = PNV_I2C(opaque);
uint32_t offset = addr >> 3;
switch (offset) {
case I2C_MODE_REG:
{
i2c->regs[offset] = val;
I2CBus *bus = pnv_i2c_get_bus(i2c);
if (!bus) {
qemu_log_mask(LOG_GUEST_ERROR, "I2C: invalid port\n");
return;
}
if (i2c_bus_busy(bus)) {
i2c->regs[I2C_STAT_REG] |= I2C_STAT_INVALID_CMD;
qemu_log_mask(LOG_GUEST_ERROR, "I2C: command in progress\n");
}
}
break;
case I2C_CMD_REG:
i2c->regs[offset] = val;
pnv_i2c_handle_cmd(i2c, val);
break;
case I2C_FIFO_REG:
i2c->regs[offset] = val;
pnv_i2c_fifo_in(i2c);
break;
case I2C_WATERMARK_REG:
i2c->regs[offset] = val;
break;
case I2C_RESET_I2C_REG:
pnv_i2c_reset(i2c);
break;
case I2C_RESET_ERRORS:
i2c->regs[I2C_STAT_REG] &= ~I2C_STAT_ANY_ERR;
i2c->regs[I2C_RESIDUAL_LEN_REG] = 0;
i2c->regs[I2C_EXTD_STAT_REG] &=
(I2C_EXTD_STAT_FIFO_SIZE | I2C_EXTD_STAT_I2C_VERSION);
fifo8_reset(&i2c->fifo);
break;
case I2C_INTR_MASK_REG:
i2c->regs[offset] = val;
break;
case I2C_INTR_MASK_OR_REG:
i2c->regs[I2C_INTR_MASK_REG] |= val;
break;
case I2C_INTR_MASK_AND_REG:
i2c->regs[I2C_INTR_MASK_REG] &= val;
break;
case I2C_PORT_BUSY_REG:
case I2C_SET_S_SCL_REG:
case I2C_RESET_S_SCL_REG:
case I2C_SET_S_SDA_REG:
case I2C_RESET_S_SDA_REG:
i2c->regs[offset] = val;
break;
default:
i2c->regs[I2C_STAT_REG] |= I2C_STAT_INVALID_CMD;
qemu_log_mask(LOG_GUEST_ERROR, "I2C: write at register: 0x%"
HWADDR_PRIx " val=0x%"PRIx64"\n", addr >> 3, val);
}
pnv_i2c_update_irq(i2c);
}
static const MemoryRegionOps pnv_i2c_xscom_ops = {
.read = pnv_i2c_xscom_read,
.write = pnv_i2c_xscom_write,
.valid.min_access_size = 8,
.valid.max_access_size = 8,
.impl.min_access_size = 8,
.impl.max_access_size = 8,
.endianness = DEVICE_BIG_ENDIAN,
};
static int pnv_i2c_bus_dt_xscom(PnvI2C *i2c, void *fdt,
int offset, int index)
{
int i2c_bus_offset;
const char i2c_compat[] =
"ibm,opal-i2c\0ibm,power8-i2c-port\0ibm,power9-i2c-port";
g_autofree char *i2c_port_name = NULL;
g_autofree char *name = g_strdup_printf("i2c-bus@%x", index);
i2c_bus_offset = fdt_add_subnode(fdt, offset, name);
_FDT(i2c_bus_offset);
_FDT((fdt_setprop_cell(fdt, i2c_bus_offset, "reg", index)));
_FDT((fdt_setprop_cell(fdt, i2c_bus_offset, "#address-cells", 1)));
_FDT((fdt_setprop_cell(fdt, i2c_bus_offset, "#size-cells", 0)));
_FDT(fdt_setprop(fdt, i2c_bus_offset, "compatible", i2c_compat,
sizeof(i2c_compat)));
_FDT((fdt_setprop_cell(fdt, i2c_bus_offset, "bus-frequency", 400000)));
i2c_port_name = g_strdup_printf("p8_%08x_e%dp%d", i2c->chip->chip_id,
i2c->engine, index);
_FDT(fdt_setprop_string(fdt, i2c_bus_offset, "ibm,port-name",
i2c_port_name));
return 0;
}
#define XSCOM_BUS_FREQUENCY 466500000
#define I2C_CLOCK_FREQUENCY (XSCOM_BUS_FREQUENCY / 4)
static int pnv_i2c_dt_xscom(PnvXScomInterface *dev, void *fdt,
int offset)
{
PnvI2C *i2c = PNV_I2C(dev);
int i2c_offset;
const char i2c_compat[] = "ibm,power8-i2cm\0ibm,power9-i2cm";
uint32_t i2c_pcba = PNV9_XSCOM_I2CM_BASE +
(i2c->engine - 1) * PNV9_XSCOM_I2CM_SIZE;
uint32_t reg[2] = {
cpu_to_be32(i2c_pcba),
cpu_to_be32(PNV9_XSCOM_I2CM_SIZE)
};
int i;
g_autofree char *name = g_strdup_printf("i2cm@%x", i2c_pcba);
i2c_offset = fdt_add_subnode(fdt, offset, name);
_FDT(i2c_offset);
_FDT(fdt_setprop(fdt, i2c_offset, "reg", reg, sizeof(reg)));
_FDT((fdt_setprop_cell(fdt, i2c_offset, "#address-cells", 1)));
_FDT((fdt_setprop_cell(fdt, i2c_offset, "#size-cells", 0)));
_FDT(fdt_setprop(fdt, i2c_offset, "compatible", i2c_compat,
sizeof(i2c_compat)));
_FDT((fdt_setprop_cell(fdt, i2c_offset, "chip-engine#", i2c->engine)));
_FDT((fdt_setprop_cell(fdt, i2c_offset, "clock-frequency",
I2C_CLOCK_FREQUENCY)));
for (i = 0; i < i2c->num_busses; i++) {
pnv_i2c_bus_dt_xscom(i2c, fdt, i2c_offset, i);
}
return 0;
}
static void pnv_i2c_sys_reset(void *dev)
{
int port;
PnvI2C *i2c = PNV_I2C(dev);
pnv_i2c_reset(dev);
/* reset all buses connected to this i2c controller */
for (port = 0; port < i2c->num_busses; port++) {
bus_cold_reset(BUS(i2c->busses[port]));
}
}
static void pnv_i2c_realize(DeviceState *dev, Error **errp)
{
PnvI2C *i2c = PNV_I2C(dev);
int i;
assert(i2c->chip);
if (i2c->num_busses > PNV_I2C_MAX_BUSSES) {
error_setg(errp, "Invalid number of busses: %u", i2c->num_busses);
return;
}
pnv_xscom_region_init(&i2c->xscom_regs, OBJECT(i2c), &pnv_i2c_xscom_ops,
i2c, "xscom-i2c", PNV9_XSCOM_I2CM_SIZE);
i2c->busses = g_new(I2CBus *, i2c->num_busses);
for (i = 0; i < i2c->num_busses; i++) {
char name[32];
snprintf(name, sizeof(name), TYPE_PNV_I2C ".%d", i);
i2c->busses[i] = i2c_init_bus(dev, name);
}
fifo8_create(&i2c->fifo, PNV_I2C_FIFO_SIZE);
qemu_register_reset(pnv_i2c_sys_reset, dev);
qdev_init_gpio_out(DEVICE(dev), &i2c->psi_irq, 1);
}
static Property pnv_i2c_properties[] = {
DEFINE_PROP_LINK("chip", PnvI2C, chip, TYPE_PNV_CHIP, PnvChip *),
DEFINE_PROP_UINT32("engine", PnvI2C, engine, 1),
DEFINE_PROP_UINT32("num-busses", PnvI2C, num_busses, 1),
DEFINE_PROP_END_OF_LIST(),
};
static void pnv_i2c_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
PnvXScomInterfaceClass *xscomc = PNV_XSCOM_INTERFACE_CLASS(klass);
xscomc->dt_xscom = pnv_i2c_dt_xscom;
/* Reason: This device is part of the CPU and cannot be used separately */
dc->user_creatable = false;
dc->desc = "PowerNV I2C";
dc->realize = pnv_i2c_realize;
device_class_set_props(dc, pnv_i2c_properties);
}
static const TypeInfo pnv_i2c_info = {
.name = TYPE_PNV_I2C,
.parent = TYPE_DEVICE,
.instance_size = sizeof(PnvI2C),
.class_init = pnv_i2c_class_init,
.interfaces = (InterfaceInfo[]) {
{ TYPE_PNV_XSCOM_INTERFACE },
{ }
}
};
static void pnv_i2c_register_types(void)
{
type_register_static(&pnv_i2c_info);
}
type_init(pnv_i2c_register_types);