esp-open-rtos/lwip/esp_interface.c
Our Air Quality f5817aef01 lwip: rework the tcp ooseq handling.
It now accounts for the number of rx pool buffers used and the
available memory when deciding the number of ooseq buffers to retain.

Enable the TCP Selective ACK support which appears to help a lot on
lossy wifi when using the OOSEQ option.
2017-09-03 20:13:54 +10:00

362 lines
12 KiB
C

/* LWIP interface to the ESP WLAN MAC layer driver.
Based on the sample driver in ethernetif.c. Tweaks based on
examining esp-lwip eagle_if.c and observed behaviour of the ESP
RTOS liblwip.a.
libnet80211.a calls into ethernetif_init & ethernetif_input.
* Copyright (c) 2001-2003 Swedish Institute of Computer Science.
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
* SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
* OF SUCH DAMAGE.
*
* This file is part of the lwIP TCP/IP stack.
*
* Original Author: Simon Goldschmidt
* Modified by Angus Gratton based on work by @kadamski/Espressif via esp-lwip project.
*/
#include <string.h>
#include "lwip/opt.h"
#include "lwip/def.h"
#include "lwip/mem.h"
#include "lwip/pbuf.h"
#include <lwip/stats.h>
#include <lwip/snmp.h>
#include "lwip/ip.h"
#include "lwip/ethip6.h"
#include "netif/etharp.h"
#include "sysparam.h"
#include "netif/ppp/pppoe.h"
#include "FreeRTOS.h"
#include "task.h"
/* declared in libnet80211.a */
int8_t sdk_ieee80211_output_pbuf(struct netif *ifp, struct pbuf* pb);
/* Define those to better describe your network interface. */
#define IFNAME0 'e'
#define IFNAME1 'n'
/**
* In this function, the hardware should be initialized.
* Called from ethernetif_init().
*
* @param netif the already initialized lwip network interface structure
* for this ethernetif
*/
static void
low_level_init(struct netif *netif)
{
/* set MAC hardware address length */
netif->hwaddr_len = ETHARP_HWADDR_LEN;
/* maximum transfer unit */
netif->mtu = 1500;
/* device capabilities */
/* don't set NETIF_FLAG_ETHARP if this device is not an ethernet one */
netif->flags = NETIF_FLAG_BROADCAST | NETIF_FLAG_ETHARP | NETIF_FLAG_LINK_UP | NETIF_FLAG_IGMP | NETIF_FLAG_MLD6;
/* Do whatever else is needed to initialize interface. */
}
/**
* This function should do the actual transmission of the packet. The packet is
* contained in the pbuf that is passed to the function. This pbuf
* might be chained.
*
* @param netif the lwip network interface structure for this ethernetif
* @param p the MAC packet to send (e.g. IP packet including MAC addresses and type)
* @return ERR_OK if the packet could be sent
* an err_t value if the packet couldn't be sent
*
* @note Returning ERR_MEM here if a DMA queue of your MAC is full can lead to
* strange results. You might consider waiting for space in the DMA queue
* to become available since the stack doesn't retry to send a packet
* dropped because of memory failure (except for the TCP timers).
*/
#define SIZEOF_STRUCT_PBUF LWIP_MEM_ALIGN_SIZE(sizeof(struct pbuf))
static err_t
low_level_output(struct netif *netif, struct pbuf *p)
{
/*
* Note the pbuf reference count is generally one here, but not always. For
* example a buffer that had been queued by etharp_query() would have had
* its reference count increased to two, and the caller will free it on that
* return path.
*/
/* If the pbuf does not have contiguous data, or there is not enough room
* for the link layer header, or there are multiple pbufs in the chain then
* clone a pbuf to output. */
if ((p->type_internal & PBUF_TYPE_FLAG_STRUCT_DATA_CONTIGUOUS) == 0 ||
(u8_t *)p->payload < (u8_t *)p + SIZEOF_STRUCT_PBUF + PBUF_LINK_ENCAPSULATION_HLEN ||
p->next) {
struct pbuf *q = pbuf_clone(PBUF_RAW_TX, PBUF_RAM, p);
if (q == NULL) {
return ERR_MEM;
}
sdk_ieee80211_output_pbuf(netif, q);
/* The sdk will pbuf_ref the pbuf before returning and free it later
* when it has been sent so free the link to it here. */
pbuf_free(q);
} else {
/* The SDK modifies the eth_hdr, well the first 12 bytes of it at least,
* but otherwise leaves the payload unmodified so it can be reused by
* the caller. The only paths that appear to reuse the pbuf are in
* tcp_out for re-transmission of TCP segments, and these paths check
* that the number of references has returned to one before reusing the
* pbuf.
*/
sdk_ieee80211_output_pbuf(netif, p);
}
LINK_STATS_INC(link.xmit);
return ERR_OK;
}
/**
* Keep account of the number the PP RX pool buffers being used in lwip,
* to help make decision about the number of OOSEQ buffers to maintain etc.
*/
uint32_t pp_rx_pool_usage;
/* Support for recycling a pbuf from the sdk rx pool, and accounting for the
* number of these used in lwip. */
void pp_recycle_rx_pbuf(struct pbuf *p)
{
LWIP_ASSERT("expected esf_buf", p->esf_buf);
sdk_system_pp_recycle_rx_pkt(p->esf_buf);
taskENTER_CRITICAL();
pp_rx_pool_usage--;
taskEXIT_CRITICAL();
}
/* Return the number of ooseq bytes that can be retained given the current
* size 'n'. */
size_t ooseq_max_bytes(size_t n)
{
size_t free = xPortGetFreeHeapSize();
size_t target = (free - 30000) + n;
if (target < 0) {
target = 0;
}
return target;
}
/* Return the number of ooseq pbufs that can be retained given the current
* size 'n'. */
size_t ooseq_max_pbufs(size_t n)
{
uint32_t usage = pp_rx_pool_usage;
size_t target = 3 - (usage - n);
if (target < 0) {
target = 0;
}
return target;
}
/**
* This function should be called when a packet is ready to be read
* from the interface. It uses the function low_level_input() that
* should handle the actual reception of bytes from the network
* interface. Then the type of the received packet is determined and
* the appropriate input function is called.
*
* @param netif the lwip network interface structure for this ethernetif
*/
/* called from ieee80211_deliver_data with new IP frames */
void ethernetif_input(struct netif *netif, struct pbuf *p)
{
struct eth_hdr *ethhdr;
if (p == NULL) {
return;
}
if (p->payload == NULL) {
return;
}
if (netif == NULL) {
return;
}
ethhdr = p->payload;
/* Account for the number of rx pool buffers being used. */
taskENTER_CRITICAL();
uint32_t usage = pp_rx_pool_usage + 1;
pp_rx_pool_usage = usage;
taskEXIT_CRITICAL();
switch(htons(ethhdr->type)) {
/* IP or ARP packet? */
case ETHTYPE_IP:
case ETHTYPE_IPV6:
#if 0
/* Simulate IP packet loss. */
if ((random() & 0xff) < 0x10) {
pbuf_free(p);
return;
}
#endif
case ETHTYPE_ARP:
#if PPPOE_SUPPORT
/* PPPoE packet? */
case ETHTYPE_PPPOEDISC:
case ETHTYPE_PPPOE:
#endif /* PPPOE_SUPPORT */
{
/* full packet send to tcpip_thread to process */
#if 0
/* Optionally copy the rx pool buffer and free it immediately. This
* helps avoid exhausting the limited rx buffer pool but uses more
* memory. */
struct pbuf *q = pbuf_clone(PBUF_RAW, PBUF_RAM, p);
pbuf_free(p);
if (q == NULL) {
return;
}
p = q;
#endif
if (netif->input(p, netif) != ERR_OK) {
LWIP_DEBUGF(NETIF_DEBUG, ("ethernetif_input: IP input error\n"));
pbuf_free(p);
p = NULL;
}
break;
}
default:
pbuf_free(p);
p = NULL;
break;
}
}
/* Since the pbuf_type definition has changed in lwip v2 and it is used by the
* sdk when calling pbuf_alloc, the SDK libraries have been modified to rename
* their references to pbuf_alloc to _pbufalloc allowing the pbuf_type to be
* rewritten here. Doing this here keeps this hack out of the lwip code, and
* ensures that this re-writing is only applied to the sdk calls to pbuf_alloc.
*
* The only pbuf types used by the SDK are type 0 for PBUF_RAM when writing
* data, and type 2 for the received data. The receive data path references
* internal buffer objects that need to be freed with custom code so a custom
* pbuf allocation type is used for these.
*
* The pbuf_layer is now also the header offset, but the sdk calls only call
* with a value of 3 which was PBUF_RAW and is now translated to a header
* offset of zero.
*/
struct pbuf *sdk_pbuf_alloc(pbuf_layer layer, u16_t length, pbuf_type type) {
if (type == 0) {
LWIP_ASSERT("Unexpected sdk_pbuf_alloc layer", layer == 3 || layer == 4);
return pbuf_alloc(PBUF_RAW_TX, length, PBUF_RAM);
} else if (type == 2) {
LWIP_ASSERT("Unexpected sdk_pbuf_alloc layer", layer == 3);
return pbuf_alloc_reference(NULL, length, PBUF_ALLOC_FLAG_RX | PBUF_TYPE_ALLOC_SRC_MASK_ESP_RX);
} else {
LWIP_ASSERT("Unexpected pbuf_alloc type", 0);
for (;;);
}
}
/**
* Should be called at the beginning of the program to set up the
* network interface. It calls the function low_level_init() to do the
* actual setup of the hardware.
*
* This function should be passed as a parameter to netif_add().
*
* @param netif the lwip network interface structure for this ethernetif
* @return ERR_OK if the loopif is initialized
* ERR_MEM if private data couldn't be allocated
* any other err_t on error
*/
err_t
ethernetif_init(struct netif *netif)
{
LWIP_ASSERT("netif != NULL", (netif != NULL));
/* The hwaddr is currently set by sdk_wifi_station_start or
* sdk_wifi_softap_start. */
#if LWIP_IPV6
// Where to do this???
netif_create_ip6_linklocal_address(netif, 1);
netif->ip6_autoconfig_enabled = 1;
printf("ip6 link local address %s\n", ip6addr_ntoa(netif_ip6_addr(netif, 0)));
#endif
#if LWIP_NETIF_HOSTNAME
/* Initialize interface hostname */
char *hostname = NULL;
/* Disabled for now as there were reports of crashes here, sysparam issues */
/* sysparam_get_string("hostname", &hostname); */
if (hostname && strlen(hostname) == 0) {
free(hostname);
hostname = NULL;
}
netif->hostname = hostname;
#endif /* LWIP_NETIF_HOSTNAME */
/*
* Initialize the snmp variables and counters inside the struct netif.
* The last argument should be replaced with your link speed, in units
* of bits per second.
*/
NETIF_INIT_SNMP(netif, snmp_ifType_ethernet_csmacd, LINK_SPEED_OF_YOUR_NETIF_IN_BPS);
// don't touch netif->state here, the field is used internally in the ESP SDK layers
netif->name[0] = IFNAME0;
netif->name[1] = IFNAME1;
/* We directly use etharp_output() here to save a function call.
* You can instead declare your own function an call etharp_output()
* from it if you have to do some checks before sending (e.g. if link
* is available...) */
#if LWIP_IPV4
netif->output = etharp_output;
#endif /* LWIP_IPV4 */
#if LWIP_IPV6
netif->output_ip6 = ethip6_output;
#endif /* LWIP_IPV6 */
netif->linkoutput = low_level_output;
/* initialize the hardware */
low_level_init(netif);
return ERR_OK;
}