1typedef struct my_custom_pbuf
2{
3   struct pbuf_custom p;
4   void* dma_descriptor;
5} my_custom_pbuf_t;
6
7LWIP_MEMPOOL_DECLARE(RX_POOL, 10, sizeof(my_custom_pbuf_t), "Zero-copy RX PBUF pool");
8
9void my_pbuf_free_custom(void* p)
10{
11  SYS_ARCH_DECL_PROTECT(old_level);
12
13  my_custom_pbuf_t* my_puf = (my_custom_pbuf_t*)p;
14
15  // invalidate data cache here - lwIP and/or application may have written into buffer!
16  // (invalidate is faster than flushing, and noone needs the correct data in the buffer)
17  invalidate_cpu_cache(p->payload, p->tot_len);
18
19  SYS_ARCH_PROTECT(old_level);
20  free_rx_dma_descriptor(my_pbuf->dma_descriptor);
21  LWIP_MEMPOOL_FREE(RX_POOL, my_pbuf);
22  SYS_ARCH_UNPROTECT(old_level);
23}
24
25void eth_rx_irq()
26{
27  dma_descriptor*   dma_desc = get_RX_DMA_descriptor_from_ethernet();
28  my_custom_pbuf_t* my_pbuf  = (my_custom_pbuf_t*)LWIP_MEMPOOL_ALLOC(RX_POOL);
29
30  my_pbuf->p.custom_free_function = my_pbuf_free_custom;
31  my_pbuf->dma_descriptor         = dma_desc;
32
33  invalidate_cpu_cache(dma_desc->rx_data, dma_desc->rx_length);
34
35  struct pbuf* p = pbuf_alloced_custom(PBUF_RAW,
36     dma_desc->rx_length,
37     PBUF_REF,
38     &my_pbuf->p,
39     dma_desc->rx_data,
40     dma_desc->max_buffer_size);
41
42  if(netif->input(p, netif) != ERR_OK) {
43    pbuf_free(p);
44  }
45}
46