xemu/hw/net/mcf_fec.c
Greg Ungerer ff1d2ac949 hw/net: handle flow control in mcf_fec driver receiver
The network mcf_fec driver emulated receive side method is not dealing
with network queue flow control properly.

Modify the receive side to check if we have enough space in the
descriptors to store the current packet. If not we process none of it
and return 0. When the guest frees up some buffers through its descriptors
we signal the qemu net layer to send more packets.

[Fixed coding style: 4-space indent and curly braces on if statement.
--Stefan]

Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Message-id: 1438045374-10358-1-git-send-email-gerg@uclinux.org
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-07-28 11:27:53 +01:00

535 lines
14 KiB
C

/*
* ColdFire Fast Ethernet Controller emulation.
*
* Copyright (c) 2007 CodeSourcery.
*
* This code is licensed under the GPL
*/
#include "hw/hw.h"
#include "net/net.h"
#include "hw/m68k/mcf.h"
#include "hw/net/mii.h"
/* For crc32 */
#include <zlib.h>
#include "exec/address-spaces.h"
//#define DEBUG_FEC 1
#ifdef DEBUG_FEC
#define DPRINTF(fmt, ...) \
do { printf("mcf_fec: " fmt , ## __VA_ARGS__); } while (0)
#else
#define DPRINTF(fmt, ...) do {} while(0)
#endif
#define FEC_MAX_FRAME_SIZE 2032
typedef struct {
MemoryRegion *sysmem;
MemoryRegion iomem;
qemu_irq *irq;
NICState *nic;
NICConf conf;
uint32_t irq_state;
uint32_t eir;
uint32_t eimr;
int rx_enabled;
uint32_t rx_descriptor;
uint32_t tx_descriptor;
uint32_t ecr;
uint32_t mmfr;
uint32_t mscr;
uint32_t rcr;
uint32_t tcr;
uint32_t tfwr;
uint32_t rfsr;
uint32_t erdsr;
uint32_t etdsr;
uint32_t emrbr;
} mcf_fec_state;
#define FEC_INT_HB 0x80000000
#define FEC_INT_BABR 0x40000000
#define FEC_INT_BABT 0x20000000
#define FEC_INT_GRA 0x10000000
#define FEC_INT_TXF 0x08000000
#define FEC_INT_TXB 0x04000000
#define FEC_INT_RXF 0x02000000
#define FEC_INT_RXB 0x01000000
#define FEC_INT_MII 0x00800000
#define FEC_INT_EB 0x00400000
#define FEC_INT_LC 0x00200000
#define FEC_INT_RL 0x00100000
#define FEC_INT_UN 0x00080000
#define FEC_EN 2
#define FEC_RESET 1
/* Map interrupt flags onto IRQ lines. */
#define FEC_NUM_IRQ 13
static const uint32_t mcf_fec_irq_map[FEC_NUM_IRQ] = {
FEC_INT_TXF,
FEC_INT_TXB,
FEC_INT_UN,
FEC_INT_RL,
FEC_INT_RXF,
FEC_INT_RXB,
FEC_INT_MII,
FEC_INT_LC,
FEC_INT_HB,
FEC_INT_GRA,
FEC_INT_EB,
FEC_INT_BABT,
FEC_INT_BABR
};
/* Buffer Descriptor. */
typedef struct {
uint16_t flags;
uint16_t length;
uint32_t data;
} mcf_fec_bd;
#define FEC_BD_R 0x8000
#define FEC_BD_E 0x8000
#define FEC_BD_O1 0x4000
#define FEC_BD_W 0x2000
#define FEC_BD_O2 0x1000
#define FEC_BD_L 0x0800
#define FEC_BD_TC 0x0400
#define FEC_BD_ABC 0x0200
#define FEC_BD_M 0x0100
#define FEC_BD_BC 0x0080
#define FEC_BD_MC 0x0040
#define FEC_BD_LG 0x0020
#define FEC_BD_NO 0x0010
#define FEC_BD_CR 0x0004
#define FEC_BD_OV 0x0002
#define FEC_BD_TR 0x0001
static void mcf_fec_read_bd(mcf_fec_bd *bd, uint32_t addr)
{
cpu_physical_memory_read(addr, bd, sizeof(*bd));
be16_to_cpus(&bd->flags);
be16_to_cpus(&bd->length);
be32_to_cpus(&bd->data);
}
static void mcf_fec_write_bd(mcf_fec_bd *bd, uint32_t addr)
{
mcf_fec_bd tmp;
tmp.flags = cpu_to_be16(bd->flags);
tmp.length = cpu_to_be16(bd->length);
tmp.data = cpu_to_be32(bd->data);
cpu_physical_memory_write(addr, &tmp, sizeof(tmp));
}
static void mcf_fec_update(mcf_fec_state *s)
{
uint32_t active;
uint32_t changed;
uint32_t mask;
int i;
active = s->eir & s->eimr;
changed = active ^s->irq_state;
for (i = 0; i < FEC_NUM_IRQ; i++) {
mask = mcf_fec_irq_map[i];
if (changed & mask) {
DPRINTF("IRQ %d = %d\n", i, (active & mask) != 0);
qemu_set_irq(s->irq[i], (active & mask) != 0);
}
}
s->irq_state = active;
}
static void mcf_fec_do_tx(mcf_fec_state *s)
{
uint32_t addr;
mcf_fec_bd bd;
int frame_size;
int len;
uint8_t frame[FEC_MAX_FRAME_SIZE];
uint8_t *ptr;
DPRINTF("do_tx\n");
ptr = frame;
frame_size = 0;
addr = s->tx_descriptor;
while (1) {
mcf_fec_read_bd(&bd, addr);
DPRINTF("tx_bd %x flags %04x len %d data %08x\n",
addr, bd.flags, bd.length, bd.data);
if ((bd.flags & FEC_BD_R) == 0) {
/* Run out of descriptors to transmit. */
break;
}
len = bd.length;
if (frame_size + len > FEC_MAX_FRAME_SIZE) {
len = FEC_MAX_FRAME_SIZE - frame_size;
s->eir |= FEC_INT_BABT;
}
cpu_physical_memory_read(bd.data, ptr, len);
ptr += len;
frame_size += len;
if (bd.flags & FEC_BD_L) {
/* Last buffer in frame. */
DPRINTF("Sending packet\n");
qemu_send_packet(qemu_get_queue(s->nic), frame, len);
ptr = frame;
frame_size = 0;
s->eir |= FEC_INT_TXF;
}
s->eir |= FEC_INT_TXB;
bd.flags &= ~FEC_BD_R;
/* Write back the modified descriptor. */
mcf_fec_write_bd(&bd, addr);
/* Advance to the next descriptor. */
if ((bd.flags & FEC_BD_W) != 0) {
addr = s->etdsr;
} else {
addr += 8;
}
}
s->tx_descriptor = addr;
}
static void mcf_fec_enable_rx(mcf_fec_state *s)
{
NetClientState *nc = qemu_get_queue(s->nic);
mcf_fec_bd bd;
mcf_fec_read_bd(&bd, s->rx_descriptor);
s->rx_enabled = ((bd.flags & FEC_BD_E) != 0);
if (s->rx_enabled) {
qemu_flush_queued_packets(nc);
}
}
static void mcf_fec_reset(mcf_fec_state *s)
{
s->eir = 0;
s->eimr = 0;
s->rx_enabled = 0;
s->ecr = 0;
s->mscr = 0;
s->rcr = 0x05ee0001;
s->tcr = 0;
s->tfwr = 0;
s->rfsr = 0x500;
}
#define MMFR_WRITE_OP (1 << 28)
#define MMFR_READ_OP (2 << 28)
#define MMFR_PHYADDR(v) (((v) >> 23) & 0x1f)
#define MMFR_REGNUM(v) (((v) >> 18) & 0x1f)
static uint64_t mcf_fec_read_mdio(mcf_fec_state *s)
{
uint64_t v;
if (s->mmfr & MMFR_WRITE_OP)
return s->mmfr;
if (MMFR_PHYADDR(s->mmfr) != 1)
return s->mmfr |= 0xffff;
switch (MMFR_REGNUM(s->mmfr)) {
case MII_BMCR:
v = MII_BMCR_SPEED | MII_BMCR_AUTOEN | MII_BMCR_FD;
break;
case MII_BMSR:
v = MII_BMSR_100TX_FD | MII_BMSR_100TX_HD | MII_BMSR_10T_FD |
MII_BMSR_10T_HD | MII_BMSR_MFPS | MII_BMSR_AN_COMP |
MII_BMSR_AUTONEG | MII_BMSR_LINK_ST;
break;
case MII_PHYID1:
v = DP83848_PHYID1;
break;
case MII_PHYID2:
v = DP83848_PHYID2;
break;
case MII_ANAR:
v = MII_ANAR_TXFD | MII_ANAR_TX | MII_ANAR_10FD |
MII_ANAR_10 | MII_ANAR_CSMACD;
break;
case MII_ANLPAR:
v = MII_ANLPAR_ACK | MII_ANLPAR_TXFD | MII_ANLPAR_TX |
MII_ANLPAR_10FD | MII_ANLPAR_10 | MII_ANLPAR_CSMACD;
break;
default:
v = 0xffff;
break;
}
s->mmfr = (s->mmfr & ~0xffff) | v;
return s->mmfr;
}
static uint64_t mcf_fec_read(void *opaque, hwaddr addr,
unsigned size)
{
mcf_fec_state *s = (mcf_fec_state *)opaque;
switch (addr & 0x3ff) {
case 0x004: return s->eir;
case 0x008: return s->eimr;
case 0x010: return s->rx_enabled ? (1 << 24) : 0; /* RDAR */
case 0x014: return 0; /* TDAR */
case 0x024: return s->ecr;
case 0x040: return mcf_fec_read_mdio(s);
case 0x044: return s->mscr;
case 0x064: return 0; /* MIBC */
case 0x084: return s->rcr;
case 0x0c4: return s->tcr;
case 0x0e4: /* PALR */
return (s->conf.macaddr.a[0] << 24) | (s->conf.macaddr.a[1] << 16)
| (s->conf.macaddr.a[2] << 8) | s->conf.macaddr.a[3];
break;
case 0x0e8: /* PAUR */
return (s->conf.macaddr.a[4] << 24) | (s->conf.macaddr.a[5] << 16) | 0x8808;
case 0x0ec: return 0x10000; /* OPD */
case 0x118: return 0;
case 0x11c: return 0;
case 0x120: return 0;
case 0x124: return 0;
case 0x144: return s->tfwr;
case 0x14c: return 0x600;
case 0x150: return s->rfsr;
case 0x180: return s->erdsr;
case 0x184: return s->etdsr;
case 0x188: return s->emrbr;
default:
hw_error("mcf_fec_read: Bad address 0x%x\n", (int)addr);
return 0;
}
}
static void mcf_fec_write(void *opaque, hwaddr addr,
uint64_t value, unsigned size)
{
mcf_fec_state *s = (mcf_fec_state *)opaque;
switch (addr & 0x3ff) {
case 0x004:
s->eir &= ~value;
break;
case 0x008:
s->eimr = value;
break;
case 0x010: /* RDAR */
if ((s->ecr & FEC_EN) && !s->rx_enabled) {
DPRINTF("RX enable\n");
mcf_fec_enable_rx(s);
}
break;
case 0x014: /* TDAR */
if (s->ecr & FEC_EN) {
mcf_fec_do_tx(s);
}
break;
case 0x024:
s->ecr = value;
if (value & FEC_RESET) {
DPRINTF("Reset\n");
mcf_fec_reset(s);
}
if ((s->ecr & FEC_EN) == 0) {
s->rx_enabled = 0;
}
break;
case 0x040:
s->mmfr = value;
s->eir |= FEC_INT_MII;
break;
case 0x044:
s->mscr = value & 0xfe;
break;
case 0x064:
/* TODO: Implement MIB. */
break;
case 0x084:
s->rcr = value & 0x07ff003f;
/* TODO: Implement LOOP mode. */
break;
case 0x0c4: /* TCR */
/* We transmit immediately, so raise GRA immediately. */
s->tcr = value;
if (value & 1)
s->eir |= FEC_INT_GRA;
break;
case 0x0e4: /* PALR */
s->conf.macaddr.a[0] = value >> 24;
s->conf.macaddr.a[1] = value >> 16;
s->conf.macaddr.a[2] = value >> 8;
s->conf.macaddr.a[3] = value;
break;
case 0x0e8: /* PAUR */
s->conf.macaddr.a[4] = value >> 24;
s->conf.macaddr.a[5] = value >> 16;
break;
case 0x0ec:
/* OPD */
break;
case 0x118:
case 0x11c:
case 0x120:
case 0x124:
/* TODO: implement MAC hash filtering. */
break;
case 0x144:
s->tfwr = value & 3;
break;
case 0x14c:
/* FRBR writes ignored. */
break;
case 0x150:
s->rfsr = (value & 0x3fc) | 0x400;
break;
case 0x180:
s->erdsr = value & ~3;
s->rx_descriptor = s->erdsr;
break;
case 0x184:
s->etdsr = value & ~3;
s->tx_descriptor = s->etdsr;
break;
case 0x188:
s->emrbr = value & 0x7f0;
break;
default:
hw_error("mcf_fec_write Bad address 0x%x\n", (int)addr);
}
mcf_fec_update(s);
}
static int mcf_fec_have_receive_space(mcf_fec_state *s, size_t want)
{
mcf_fec_bd bd;
uint32_t addr;
/* Walk descriptor list to determine if we have enough buffer */
addr = s->rx_descriptor;
while (want > 0) {
mcf_fec_read_bd(&bd, addr);
if ((bd.flags & FEC_BD_E) == 0) {
return 0;
}
if (want < s->emrbr) {
return 1;
}
want -= s->emrbr;
/* Advance to the next descriptor. */
if ((bd.flags & FEC_BD_W) != 0) {
addr = s->erdsr;
} else {
addr += 8;
}
}
return 0;
}
static ssize_t mcf_fec_receive(NetClientState *nc, const uint8_t *buf, size_t size)
{
mcf_fec_state *s = qemu_get_nic_opaque(nc);
mcf_fec_bd bd;
uint32_t flags = 0;
uint32_t addr;
uint32_t crc;
uint32_t buf_addr;
uint8_t *crc_ptr;
unsigned int buf_len;
size_t retsize;
DPRINTF("do_rx len %d\n", size);
if (!s->rx_enabled) {
return -1;
}
/* 4 bytes for the CRC. */
size += 4;
crc = cpu_to_be32(crc32(~0, buf, size));
crc_ptr = (uint8_t *)&crc;
/* Huge frames are truncted. */
if (size > FEC_MAX_FRAME_SIZE) {
size = FEC_MAX_FRAME_SIZE;
flags |= FEC_BD_TR | FEC_BD_LG;
}
/* Frames larger than the user limit just set error flags. */
if (size > (s->rcr >> 16)) {
flags |= FEC_BD_LG;
}
/* Check if we have enough space in current descriptors */
if (!mcf_fec_have_receive_space(s, size)) {
return 0;
}
addr = s->rx_descriptor;
retsize = size;
while (size > 0) {
mcf_fec_read_bd(&bd, addr);
buf_len = (size <= s->emrbr) ? size: s->emrbr;
bd.length = buf_len;
size -= buf_len;
DPRINTF("rx_bd %x length %d\n", addr, bd.length);
/* The last 4 bytes are the CRC. */
if (size < 4)
buf_len += size - 4;
buf_addr = bd.data;
cpu_physical_memory_write(buf_addr, buf, buf_len);
buf += buf_len;
if (size < 4) {
cpu_physical_memory_write(buf_addr + buf_len, crc_ptr, 4 - size);
crc_ptr += 4 - size;
}
bd.flags &= ~FEC_BD_E;
if (size == 0) {
/* Last buffer in frame. */
bd.flags |= flags | FEC_BD_L;
DPRINTF("rx frame flags %04x\n", bd.flags);
s->eir |= FEC_INT_RXF;
} else {
s->eir |= FEC_INT_RXB;
}
mcf_fec_write_bd(&bd, addr);
/* Advance to the next descriptor. */
if ((bd.flags & FEC_BD_W) != 0) {
addr = s->erdsr;
} else {
addr += 8;
}
}
s->rx_descriptor = addr;
mcf_fec_enable_rx(s);
mcf_fec_update(s);
return retsize;
}
static const MemoryRegionOps mcf_fec_ops = {
.read = mcf_fec_read,
.write = mcf_fec_write,
.endianness = DEVICE_NATIVE_ENDIAN,
};
static NetClientInfo net_mcf_fec_info = {
.type = NET_CLIENT_OPTIONS_KIND_NIC,
.size = sizeof(NICState),
.receive = mcf_fec_receive,
};
void mcf_fec_init(MemoryRegion *sysmem, NICInfo *nd,
hwaddr base, qemu_irq *irq)
{
mcf_fec_state *s;
qemu_check_nic_model(nd, "mcf_fec");
s = (mcf_fec_state *)g_malloc0(sizeof(mcf_fec_state));
s->sysmem = sysmem;
s->irq = irq;
memory_region_init_io(&s->iomem, NULL, &mcf_fec_ops, s, "fec", 0x400);
memory_region_add_subregion(sysmem, base, &s->iomem);
s->conf.macaddr = nd->macaddr;
s->conf.peers.ncs[0] = nd->netdev;
s->nic = qemu_new_nic(&net_mcf_fec_info, &s->conf, nd->model, nd->name, s);
qemu_format_nic_info_str(qemu_get_queue(s->nic), s->conf.macaddr.a);
}