+static void pasemi_mac_queue_csdesc(const struct sk_buff *skb,
+ const dma_addr_t *map,
+ const unsigned int *map_size,
+ struct pasemi_mac_txring *txring,
+ struct pasemi_mac_csring *csring)
+{
+ u64 fund;
+ dma_addr_t cs_dest;
+ const int nh_off = skb_network_offset(skb);
+ const int nh_len = skb_network_header_len(skb);
+ const int nfrags = skb_shinfo(skb)->nr_frags;
+ int cs_size, i, fill, hdr, cpyhdr, evt;
+ dma_addr_t csdma;
+
+ fund = XCT_FUN_ST | XCT_FUN_RR_8BRES |
+ XCT_FUN_O | XCT_FUN_FUN(csring->fun) |
+ XCT_FUN_CRM_SIG | XCT_FUN_LLEN(skb->len - nh_off) |
+ XCT_FUN_SHL(nh_len >> 2) | XCT_FUN_SE;
+
+ switch (ip_hdr(skb)->protocol) {
+ case IPPROTO_TCP:
+ fund |= XCT_FUN_SIG_TCP4;
+ /* TCP checksum is 16 bytes into the header */
+ cs_dest = map[0] + skb_transport_offset(skb) + 16;
+ break;
+ case IPPROTO_UDP:
+ fund |= XCT_FUN_SIG_UDP4;
+ /* UDP checksum is 6 bytes into the header */
+ cs_dest = map[0] + skb_transport_offset(skb) + 6;
+ break;
+ default:
+ BUG();
+ }
+
+ /* Do the checksum offloaded */
+ fill = csring->next_to_fill;
+ hdr = fill;
+
+ CS_DESC(csring, fill++) = fund;
+ /* Room for 8BRES. Checksum result is really 2 bytes into it */
+ csdma = csring->chan.ring_dma + (fill & (CS_RING_SIZE-1)) * 8 + 2;
+ CS_DESC(csring, fill++) = 0;
+
+ CS_DESC(csring, fill) = XCT_PTR_LEN(map_size[0]-nh_off) | XCT_PTR_ADDR(map[0]+nh_off);
+ for (i = 1; i <= nfrags; i++)
+ CS_DESC(csring, fill+i) = XCT_PTR_LEN(map_size[i]) | XCT_PTR_ADDR(map[i]);
+
+ fill += i;
+ if (fill & 1)
+ fill++;
+
+ /* Copy the result into the TCP packet */
+ cpyhdr = fill;
+ CS_DESC(csring, fill++) = XCT_FUN_O | XCT_FUN_FUN(csring->fun) |
+ XCT_FUN_LLEN(2) | XCT_FUN_SE;
+ CS_DESC(csring, fill++) = XCT_PTR_LEN(2) | XCT_PTR_ADDR(cs_dest) | XCT_PTR_T;
+ CS_DESC(csring, fill++) = XCT_PTR_LEN(2) | XCT_PTR_ADDR(csdma);
+ fill++;
+
+ evt = !csring->last_event;
+ csring->last_event = evt;
+
+ /* Event handshaking with MAC TX */
+ CS_DESC(csring, fill++) = CTRL_CMD_T | CTRL_CMD_META_EVT | CTRL_CMD_O |
+ CTRL_CMD_ETYPE_SET | CTRL_CMD_REG(csring->events[evt]);
+ CS_DESC(csring, fill++) = 0;
+ CS_DESC(csring, fill++) = CTRL_CMD_T | CTRL_CMD_META_EVT | CTRL_CMD_O |
+ CTRL_CMD_ETYPE_WCLR | CTRL_CMD_REG(csring->events[!evt]);
+ CS_DESC(csring, fill++) = 0;
+ csring->next_to_fill = fill & (CS_RING_SIZE-1);
+
+ cs_size = fill - hdr;
+ write_dma_reg(PAS_DMA_TXCHAN_INCR(csring->chan.chno), (cs_size) >> 1);
+
+ /* TX-side event handshaking */
+ fill = txring->next_to_fill;
+ TX_DESC(txring, fill++) = CTRL_CMD_T | CTRL_CMD_META_EVT | CTRL_CMD_O |
+ CTRL_CMD_ETYPE_WSET | CTRL_CMD_REG(csring->events[evt]);
+ TX_DESC(txring, fill++) = 0;
+ TX_DESC(txring, fill++) = CTRL_CMD_T | CTRL_CMD_META_EVT | CTRL_CMD_O |
+ CTRL_CMD_ETYPE_CLR | CTRL_CMD_REG(csring->events[!evt]);
+ TX_DESC(txring, fill++) = 0;
+ txring->next_to_fill = fill;
+
+ write_dma_reg(PAS_DMA_TXCHAN_INCR(txring->chan.chno), 2);
+
+ return;
+}
+