u-boot/drivers/net/sandbox-raw.c
Simon Glass a1ca92eaaf dm: eth: Avoid blocking on packet reception
Some devices can take a long time to work out whether they have a new packet
or now. For example the ASIX USB Ethernet dongle can take 5 seconds to do
this, since it waits until it gets a new packet on the wire before allowing
the USB bulk read packet to be submitted.

At present with driver mode the Ethernet receive code reads 32 packets. This
can take a very long time if we must wait for all 32 packets. The old code
(before driver model) worked by reading a single set of packets from the USB
device, then processing all the packets with in. It would be nice to use
the same behaviour with driver model.

Add a flag to the receive method which indicates that the driver should try
to find a packet if available, by consulting the hardware. When the flag is
not set, it should just return any packet data it has already received. If
there is none, it should return -EAGAIN so that the loop will terminate.

Signed-off-by: Simon Glass <sjg@chromium.org>
2015-07-21 17:39:40 -06:00

165 lines
4.3 KiB
C

/*
* Copyright (c) 2015 National Instruments
*
* (C) Copyright 2015
* Joe Hershberger <joe.hershberger@ni.com>
*
* SPDX-License-Identifier: GPL-2.0
*/
#include <asm/eth-raw-os.h>
#include <common.h>
#include <dm.h>
#include <malloc.h>
#include <net.h>
DECLARE_GLOBAL_DATA_PTR;
static int reply_arp;
static struct in_addr arp_ip;
static int sb_eth_raw_start(struct udevice *dev)
{
struct eth_sandbox_raw_priv *priv = dev_get_priv(dev);
struct eth_pdata *pdata = dev_get_platdata(dev);
const char *interface;
debug("eth_sandbox_raw: Start\n");
interface = fdt_getprop(gd->fdt_blob, dev->of_offset,
"host-raw-interface", NULL);
if (interface == NULL)
return -EINVAL;
if (strcmp(interface, "lo") == 0) {
priv->local = 1;
setenv("ipaddr", "127.0.0.1");
setenv("serverip", "127.0.0.1");
}
return sandbox_eth_raw_os_start(interface, pdata->enetaddr, priv);
}
static int sb_eth_raw_send(struct udevice *dev, void *packet, int length)
{
struct eth_sandbox_raw_priv *priv = dev_get_priv(dev);
debug("eth_sandbox_raw: Send packet %d\n", length);
if (priv->local) {
struct ethernet_hdr *eth = packet;
if (ntohs(eth->et_protlen) == PROT_ARP) {
struct arp_hdr *arp = packet + ETHER_HDR_SIZE;
/**
* localhost works on a higher-level API in Linux than
* ARP packets, so fake it
*/
arp_ip = net_read_ip(&arp->ar_tpa);
reply_arp = 1;
return 0;
}
packet += ETHER_HDR_SIZE;
length -= ETHER_HDR_SIZE;
}
return sandbox_eth_raw_os_send(packet, length, priv);
}
static int sb_eth_raw_recv(struct udevice *dev, int flags, uchar **packetp)
{
struct eth_pdata *pdata = dev_get_platdata(dev);
struct eth_sandbox_raw_priv *priv = dev_get_priv(dev);
int retval = 0;
int length;
if (reply_arp) {
struct arp_hdr *arp = (void *)net_rx_packets[0] +
ETHER_HDR_SIZE;
/*
* Fake an ARP response. The u-boot network stack is sending an
* ARP request (to find the MAC address to address the actual
* packet to) and requires an ARP response to continue. Since
* this is the localhost interface, there is no Etherent level
* traffic at all, so there is no way to send an ARP request or
* to get a response. For this reason we fake the response to
* make the u-boot network stack happy.
*/
arp->ar_hrd = htons(ARP_ETHER);
arp->ar_pro = htons(PROT_IP);
arp->ar_hln = ARP_HLEN;
arp->ar_pln = ARP_PLEN;
arp->ar_op = htons(ARPOP_REPLY);
/* Any non-zero MAC address will work */
memset(&arp->ar_sha, 0x01, ARP_HLEN);
/* Use whatever IP we were looking for (always 127.0.0.1?) */
net_write_ip(&arp->ar_spa, arp_ip);
memcpy(&arp->ar_tha, pdata->enetaddr, ARP_HLEN);
net_write_ip(&arp->ar_tpa, net_ip);
length = ARP_HDR_SIZE;
} else {
/* If local, the Ethernet header won't be included; skip it */
uchar *pktptr = priv->local ?
net_rx_packets[0] + ETHER_HDR_SIZE : net_rx_packets[0];
retval = sandbox_eth_raw_os_recv(pktptr, &length, priv);
}
if (!retval && length) {
if (priv->local) {
struct ethernet_hdr *eth = (void *)net_rx_packets[0];
/* Fill in enough of the missing Ethernet header */
memcpy(eth->et_dest, pdata->enetaddr, ARP_HLEN);
memset(eth->et_src, 0x01, ARP_HLEN);
eth->et_protlen = htons(reply_arp ? PROT_ARP : PROT_IP);
reply_arp = 0;
length += ETHER_HDR_SIZE;
}
debug("eth_sandbox_raw: received packet %d\n",
length);
*packetp = net_rx_packets[0];
return length;
}
return retval;
}
static void sb_eth_raw_stop(struct udevice *dev)
{
struct eth_sandbox_raw_priv *priv = dev_get_priv(dev);
debug("eth_sandbox_raw: Stop\n");
sandbox_eth_raw_os_stop(priv);
}
static const struct eth_ops sb_eth_raw_ops = {
.start = sb_eth_raw_start,
.send = sb_eth_raw_send,
.recv = sb_eth_raw_recv,
.stop = sb_eth_raw_stop,
};
static int sb_eth_raw_ofdata_to_platdata(struct udevice *dev)
{
struct eth_pdata *pdata = dev_get_platdata(dev);
pdata->iobase = dev_get_addr(dev);
return 0;
}
static const struct udevice_id sb_eth_raw_ids[] = {
{ .compatible = "sandbox,eth-raw" },
{ }
};
U_BOOT_DRIVER(eth_sandbox_raw) = {
.name = "eth_sandbox_raw",
.id = UCLASS_ETH,
.of_match = sb_eth_raw_ids,
.ofdata_to_platdata = sb_eth_raw_ofdata_to_platdata,
.ops = &sb_eth_raw_ops,
.priv_auto_alloc_size = sizeof(struct eth_sandbox_raw_priv),
.platdata_auto_alloc_size = sizeof(struct eth_pdata),
};