/*
* QEMU model of the Milkymist minimac2 block.
*
* Copyright (c) 2011 Michael Walle <michael@walle.cc>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
*
*
* Specification available at:
* not available yet
*
*/
#include "hw/hw.h"
#include "hw/sysbus.h"
#include "trace.h"
#include "net/net.h"
#include "qemu/error-report.h"
#include <zlib.h>
enum {
R_SETUP = 0,
R_MDIO,
R_STATE0,
R_COUNT0,
R_STATE1,
R_COUNT1,
R_TXCOUNT,
R_MAX
};
enum {
SETUP_PHY_RST = (1<<0),
};
enum {
MDIO_DO = (1<<0),
MDIO_DI = (1<<1),
MDIO_OE = (1<<2),
MDIO_CLK = (1<<3),
};
enum {
STATE_EMPTY = 0,
STATE_LOADED = 1,
STATE_PENDING = 2,
};
enum {
MDIO_OP_WRITE = 1,
MDIO_OP_READ = 2,
};
enum mdio_state {
MDIO_STATE_IDLE,
MDIO_STATE_READING,
MDIO_STATE_WRITING,
};
enum {
R_PHY_ID1 = 2,
R_PHY_ID2 = 3,
R_PHY_MAX = 32
};
#define MINIMAC2_MTU 1530
#define MINIMAC2_BUFFER_SIZE 2048
struct MilkymistMinimac2MdioState {
int last_clk;
int count;
uint32_t data;
uint16_t data_out;
int state;
uint8_t phy_addr;
uint8_t reg_addr;
};
typedef struct MilkymistMinimac2MdioState MilkymistMinimac2MdioState;
#define TYPE_MILKYMIST_MINIMAC2 "milkymist-minimac2"
#define MILKYMIST_MINIMAC2(obj) \
OBJECT_CHECK(MilkymistMinimac2State, (obj), TYPE_MILKYMIST_MINIMAC2)
struct MilkymistMinimac2State {
SysBusDevice parent_obj;
NICState *nic;
NICConf conf;
char *phy_model;
MemoryRegion buffers;
MemoryRegion regs_region;
qemu_irq rx_irq;
qemu_irq tx_irq;
uint32_t regs[R_MAX];
MilkymistMinimac2MdioState mdio;
uint16_t phy_regs[R_PHY_MAX];
uint8_t *rx0_buf;
uint8_t *rx1_buf;
uint8_t *tx_buf;
};
typedef struct MilkymistMinimac2State MilkymistMinimac2State;
static const uint8_t preamble_sfd[] = {
0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0xd5
};
static void minimac2_mdio_write_reg(MilkymistMinimac2State *s,
uint8_t phy_addr, uint8_t reg_addr, uint16_t value)
{
trace_milkymist_minimac2_mdio_write(phy_addr, reg_addr, value);
/* nop */
}
static uint16_t minimac2_mdio_read_reg(MilkymistMinimac2State *s,
uint8_t phy_addr, uint8_t reg_addr)
{
uint16_t r = s->phy_regs[reg_addr];
trace_milkymist_minimac2_mdio_read(phy_addr, reg_addr, r);
return r;
}
static void minimac2_update_mdio(MilkymistMinimac2State *s)
{
MilkymistMinimac2MdioState *m = &s->mdio;
/* detect rising clk edge */
if (m->last_clk == 0 && (s->regs[R_MDIO] & MDIO_CLK)) {
/* shift data in */
int bit = ((s->regs[R_MDIO] & MDIO_DO)
&& (s->regs[R_MDIO] & MDIO_OE)) ? 1 : 0;
m->data = (m->data << 1) | bit;
/* check for sync */
if (m->data == 0xffffffff) {
m->count = 32;
}
if (m->count == 16) {
uint8_t start = (m->data >> 14) & 0x3;
uint8_t op = (m->data >> 12) & 0x3;
uint8_t ta = (m->data) & 0x3;
if (start == 1 && op == MDIO_OP_WRITE && ta == 2) {
m->state = MDIO_STATE_WRITING;
} else if (start == 1 && op == MDIO_OP_READ && (ta & 1) == 0) {
m->state = MDIO_STATE_READING;
} else {
m->state = MDIO_STATE_IDLE;
}
if (m->state != MDIO_STATE_IDLE) {
m->phy_addr = (m->data >> 7) & 0x1f;
m->reg_addr = (m->data >> 2) & 0x1f;
}
if (m->state == MDIO_STATE_READING) {
m->data_out = minimac2_mdio_read_reg(s, m->phy_addr,
m->reg_addr);
}
}
if (m->count < 16 && m->state == MDIO_STATE_READING) {
int bit = (m->data_out & 0x8000) ? 1 : 0;
m->data_out <<= 1;
if (bit) {
s->regs[R_MDIO] |= MDIO_DI;
} else {
s->regs[R_MDIO] &= ~MDIO_DI;
}
}
if (m->count == 0 && m->state) {
if (m->state == MDIO_STATE_WRITING) {
uint16_t data = m->data & 0xffff;
minimac2_mdio_write_reg(s, m->phy_addr, m->reg_addr, data);
}
m->state = MDIO_STATE_IDLE;
}
m->count--;
}
m->last_clk = (s->regs[R_MDIO] & MDIO_CLK) ? 1 : 0;
}
static size_t assemble_frame(uint8_t *buf, size_t size,
const uint8_t *payload, size_t payload_size)
{
uint32_t crc;
if (size < payload_size + 12) {
error_report("milkymist_minimac2: received too big ethernet frame");
return 0;
}
/* prepend preamble and sfd */
memcpy(buf, preamble_sfd, 8);
/* now copy the payload */
memcpy(buf + 8, payload, payload_size);
/* pad frame if needed */
if (payload_size < 60) {
memset(buf + payload_size + 8, 0, 60 - payload_size);
payload_size = 60;
}
/* append fcs */
crc = cpu_to_le32(crc32(0, buf + 8, payload_size));
memcpy(buf + payload_size + 8, &crc, 4);
return payload_size + 12;
}
static void minimac2_tx(MilkymistMinimac2State *s)
{
uint32_t txcount = s->regs[R_TXCOUNT];
uint8_t *buf = s->tx_buf;
if (txcount < 64) {
error_report("milkymist_minimac2: ethernet frame too small (%u < %u)",
txcount, 64);
goto err;
}
if (txcount > MINIMAC2_MTU) {
error_report("milkymist_minimac2: MTU exceeded (%u > %u)",
txcount, MINIMAC2_MTU);
goto err;
}
if (memcmp(buf, preamble_sfd, 8) != 0) {
error_report("milkymist_minimac2: frame doesn't contain the preamble "
"and/or the SFD (%02x %02x %02x %02x %02x %02x %02x %02x)",
buf[0], buf[1], buf[2], buf[3], buf[4], buf[5], buf[6], buf[7]);
goto err;
}
trace_milkymist_minimac2_tx_frame(txcount - 12);
/* send packet, skipping preamble and sfd */
qemu_send_packet_raw(qemu_get_queue(s->nic), buf + 8, txcount - 12);
s->regs[R_TXCOUNT] = 0;
err:
trace_milkymist_minimac2_pulse_irq_tx();
qemu_irq_pulse(s->tx_irq);
}
static void update_rx_interrupt(MilkymistMinimac2State *s)
{
if (s->regs[R_STATE0] == STATE_PENDING
|| s->regs[R_STATE1] == STATE_PENDING) {
trace_milkymist_minimac2_raise_irq_rx();
qemu_irq_raise(s->rx_irq);
} else {
trace_milkymist_minimac2_lower_irq_rx();
qemu_irq_lower(s->rx_irq);
}
}
static ssize_t minimac2_rx(NetClientState *nc, const uint8_t *buf, size_t size)
{
MilkymistMinimac2State *s = qemu_get_nic_opaque(nc);
uint32_t r_count;
uint32_t r_state;
uint8_t *rx_buf;
size_t frame_size;
trace_milkymist_minimac2_rx_frame(buf, size);
/* choose appropriate slot */
if (s->regs[R_STATE0] == STATE_LOADED) {
r_count = R_COUNT0;
r_state = R_STATE0;
rx_buf = s->rx0_buf;
} else if (s->regs[R_STATE1] == STATE_LOADED) {
r_count = R_COUNT1;
r_state = R_STATE1;
rx_buf = s->rx1_buf;
} else {
trace_milkymist_minimac2_drop_rx_frame(buf);
return size;
}
/* assemble frame */
frame_size = assemble_frame(rx_buf, MINIMAC2_BUFFER_SIZE, buf, size);
if (frame_size == 0) {
return size;
}
trace_milkymist_minimac2_rx_transfer(rx_buf, frame_size);
/* update slot */
s->regs[r_count] = frame_size;
s->regs[r_state] = STATE_PENDING;
update_rx_interrupt(s);
return size;
}
static uint64_t
minimac2_read(void *opaque, hwaddr addr, unsigned size)
{
MilkymistMinimac2State *s = opaque;
uint32_t r = 0;
addr >>= 2;
switch (addr) {
case R_SETUP:
case R_MDIO:
case R_STATE0:
case R_COUNT0:
case R_STATE1:
case R_COUNT1:
case R_TXCOUNT:
r = s->regs[addr];
break;
default:
error_report("milkymist_minimac2: read access to unknown register 0x"
TARGET_FMT_plx, addr << 2);
break;
}
trace_milkymist_minimac2_memory_read(addr << 2, r);
return r;
}
static void
minimac2_write(void *opaque, hwaddr addr, uint64_t value,
unsigned size)
{
MilkymistMinimac2State *s = opaque;
trace_milkymist_minimac2_memory_write(addr, value);
addr >>= 2;
switch (addr) {
case R_MDIO:
{
/* MDIO_DI is read only */
int mdio_di = (s->regs[R_MDIO] & MDIO_DI);
s->regs[R_MDIO] = value;
if (mdio_di) {
s->regs[R_MDIO] |= mdio_di;
} else {
s->regs[R_MDIO] &= ~mdio_di;
}
minimac2_update_mdio(s);
} break;
case R_TXCOUNT:
s->regs[addr] = value;
if (value > 0) {
minimac2_tx(s);
}
break;
case R_STATE0:
case R_STATE1:
s->regs[addr] = value;
update_rx_interrupt(s);
break;
case R_SETUP:
case R_COUNT0:
case R_COUNT1:
s->regs[addr] = value;
break;
default:
error_report("milkymist_minimac2: write access to unknown register 0x"
TARGET_FMT_plx, addr << 2);
break;
}
}
static const MemoryRegionOps minimac2_ops = {
.read = minimac2_read,
.write = minimac2_write,
.valid = {
.min_access_size = 4,
.max_access_size = 4,
},
.endianness = DEVICE_NATIVE_ENDIAN,
};
static int minimac2_can_rx(NetClientState *nc)
{
MilkymistMinimac2State *s = qemu_get_nic_opaque(nc);
if (s->regs[R_STATE0] == STATE_LOADED) {
return 1;
}
if (s->regs[R_STATE1] == STATE_LOADED) {
return 1;
}
return 0;
}
static void minimac2_cleanup(NetClientState *nc)
{
MilkymistMinimac2State *s = qemu_get_nic_opaque(nc);
s->nic = NULL;
}
static void milkymist_minimac2_reset(DeviceState *d)
{
MilkymistMinimac2State *s = MILKYMIST_MINIMAC2(d);
int i;
for (i = 0; i < R_MAX; i++) {
s->regs[i] = 0;
}
for (i = 0; i < R_PHY_MAX; i++) {
s->phy_regs[i] = 0;
}
/* defaults */
s->phy_regs[R_PHY_ID1] = 0x0022; /* Micrel KSZ8001L */
s->phy_regs[R_PHY_ID2] = 0x161a;
}
static NetClientInfo net_milkymist_minimac2_info = {
.type = NET_CLIENT_OPTIONS_KIND_NIC,
.size = sizeof(NICState),
.can_receive = minimac2_can_rx,
.receive = minimac2_rx,
.cleanup = minimac2_cleanup,
};
static int milkymist_minimac2_init(SysBusDevice *sbd)
{
DeviceState *dev = DEVICE(sbd);
MilkymistMinimac2State *s = MILKYMIST_MINIMAC2(dev);
size_t buffers_size = TARGET_PAGE_ALIGN(3 * MINIMAC2_BUFFER_SIZE);
sysbus_init_irq(sbd, &s->rx_irq);
sysbus_init_irq(sbd, &s->tx_irq);
memory_region_init_io(&s->regs_region, OBJECT(dev), &minimac2_ops, s,
"milkymist-minimac2", R_MAX * 4);
sysbus_init_mmio(sbd, &s->regs_region);
/* register buffers memory */
memory_region_init_ram(&s->buffers, OBJECT(dev), "milkymist-minimac2.buffers",
buffers_size);
vmstate_register_ram_global(&s->buffers);
s->rx0_buf = memory_region_get_ram_ptr(&s->buffers);
s->rx1_buf = s->rx0_buf + MINIMAC2_BUFFER_SIZE;
s->tx_buf = s->rx1_buf + MINIMAC2_BUFFER_SIZE;
sysbus_init_mmio(sbd, &s->buffers);
qemu_macaddr_default_if_unset(&s->conf.macaddr);
s->nic = qemu_new_nic(&net_milkymist_minimac2_info, &s->conf,
object_get_typename(OBJECT(dev)), dev->id, s);
qemu_format_nic_info_str(qemu_get_queue(s->nic), s->conf.macaddr.a);
return 0;
}
static const VMStateDescription vmstate_milkymist_minimac2_mdio = {
.name = "milkymist-minimac2-mdio",
.version_id = 1,
.minimum_version_id = 1,
.fields = (VMStateField[]) {
VMSTATE_INT32(last_clk, MilkymistMinimac2MdioState),
VMSTATE_INT32(count, MilkymistMinimac2MdioState),
VMSTATE_UINT32(data, MilkymistMinimac2MdioState),
VMSTATE_UINT16(data_out, MilkymistMinimac2MdioState),
VMSTATE_INT32(state, MilkymistMinimac2MdioState),
VMSTATE_UINT8(phy_addr, MilkymistMinimac2MdioState),
VMSTATE_UINT8(reg_addr, MilkymistMinimac2MdioState),
VMSTATE_END_OF_LIST()
}
};
static const VMStateDescription vmstate_milkymist_minimac2 = {
.name = "milkymist-minimac2",
.version_id = 1,
.minimum_version_id = 1,
.fields = (VMStateField[]) {
VMSTATE_UINT32_ARRAY(regs, MilkymistMinimac2State, R_MAX),
VMSTATE_UINT16_ARRAY(phy_regs, MilkymistMinimac2State, R_PHY_MAX),
VMSTATE_STRUCT(mdio, MilkymistMinimac2State, 0,
vmstate_milkymist_minimac2_mdio, MilkymistMinimac2MdioState),
VMSTATE_END_OF_LIST()
}
};
static Property milkymist_minimac2_properties[] = {
DEFINE_NIC_PROPERTIES(MilkymistMinimac2State, conf),
DEFINE_PROP_STRING("phy_model", MilkymistMinimac2State, phy_model),
DEFINE_PROP_END_OF_LIST(),
};
static void milkymist_minimac2_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
k->init = milkymist_minimac2_init;
dc->reset = milkymist_minimac2_reset;
dc->vmsd = &vmstate_milkymist_minimac2;
dc->props = milkymist_minimac2_properties;
}
static const TypeInfo milkymist_minimac2_info = {
.name = TYPE_MILKYMIST_MINIMAC2,
.parent = TYPE_SYS_BUS_DEVICE,
.instance_size = sizeof(MilkymistMinimac2State),
.class_init = milkymist_minimac2_class_init,
};
static void milkymist_minimac2_register_types(void)
{
type_register_static(&milkymist_minimac2_info);
}
type_init(milkymist_minimac2_register_types)
