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v4.6
 
  1/*
  2 * This file is based on code from OCTEON SDK by Cavium Networks.
  3 *
  4 * Copyright (c) 2003-2010 Cavium Networks
  5 *
  6 * This file is free software; you can redistribute it and/or modify
  7 * it under the terms of the GNU General Public License, Version 2, as
  8 * published by the Free Software Foundation.
  9 */
 10
 11#include <linux/module.h>
 12#include <linux/kernel.h>
 13#include <linux/netdevice.h>
 14#include <linux/etherdevice.h>
 15#include <linux/ip.h>
 16#include <linux/ratelimit.h>
 17#include <linux/string.h>
 18#include <linux/interrupt.h>
 19#include <net/dst.h>
 20#ifdef CONFIG_XFRM
 21#include <linux/xfrm.h>
 22#include <net/xfrm.h>
 23#endif /* CONFIG_XFRM */
 24
 25#include <linux/atomic.h>
 
 26
 27#include <asm/octeon/octeon.h>
 28
 29#include "ethernet-defines.h"
 30#include "octeon-ethernet.h"
 
 31#include "ethernet-tx.h"
 32#include "ethernet-util.h"
 33
 34#include <asm/octeon/cvmx-wqe.h>
 35#include <asm/octeon/cvmx-fau.h>
 36#include <asm/octeon/cvmx-pip.h>
 37#include <asm/octeon/cvmx-pko.h>
 38#include <asm/octeon/cvmx-helper.h>
 39
 40#include <asm/octeon/cvmx-gmxx-defs.h>
 41
 42#define CVM_OCT_SKB_CB(skb)	((u64 *)((skb)->cb))
 43
 44/*
 45 * You can define GET_SKBUFF_QOS() to override how the skbuff output
 46 * function determines which output queue is used. The default
 47 * implementation always uses the base queue for the port. If, for
 48 * example, you wanted to use the skb->priority field, define
 49 * GET_SKBUFF_QOS as: #define GET_SKBUFF_QOS(skb) ((skb)->priority)
 50 */
 51#ifndef GET_SKBUFF_QOS
 52#define GET_SKBUFF_QOS(skb) 0
 53#endif
 54
 55static void cvm_oct_tx_do_cleanup(unsigned long arg);
 56static DECLARE_TASKLET(cvm_oct_tx_cleanup_tasklet, cvm_oct_tx_do_cleanup, 0);
 57
 58/* Maximum number of SKBs to try to free per xmit packet. */
 59#define MAX_SKB_TO_FREE (MAX_OUT_QUEUE_DEPTH * 2)
 60
 61static inline int32_t cvm_oct_adjust_skb_to_free(int32_t skb_to_free, int fau)
 62{
 63	int32_t undo;
 64
 65	undo = skb_to_free > 0 ? MAX_SKB_TO_FREE : skb_to_free +
 66						   MAX_SKB_TO_FREE;
 67	if (undo > 0)
 68		cvmx_fau_atomic_add32(fau, -undo);
 69	skb_to_free = -skb_to_free > MAX_SKB_TO_FREE ? MAX_SKB_TO_FREE :
 70						       -skb_to_free;
 71	return skb_to_free;
 72}
 73
 74static void cvm_oct_kick_tx_poll_watchdog(void)
 75{
 76	union cvmx_ciu_timx ciu_timx;
 77
 78	ciu_timx.u64 = 0;
 79	ciu_timx.s.one_shot = 1;
 80	ciu_timx.s.len = cvm_oct_tx_poll_interval;
 81	cvmx_write_csr(CVMX_CIU_TIMX(1), ciu_timx.u64);
 82}
 83
 84static void cvm_oct_free_tx_skbs(struct net_device *dev)
 85{
 86	int32_t skb_to_free;
 87	int qos, queues_per_port;
 88	int total_freed = 0;
 89	int total_remaining = 0;
 90	unsigned long flags;
 91	struct octeon_ethernet *priv = netdev_priv(dev);
 92
 93	queues_per_port = cvmx_pko_get_num_queues(priv->port);
 94	/* Drain any pending packets in the free list */
 95	for (qos = 0; qos < queues_per_port; qos++) {
 96		if (skb_queue_len(&priv->tx_free_list[qos]) == 0)
 97			continue;
 98		skb_to_free = cvmx_fau_fetch_and_add32(priv->fau + qos * 4,
 99						       MAX_SKB_TO_FREE);
100		skb_to_free = cvm_oct_adjust_skb_to_free(skb_to_free,
101							 priv->fau + qos * 4);
102		total_freed += skb_to_free;
103		if (skb_to_free > 0) {
104			struct sk_buff *to_free_list = NULL;
105
106			spin_lock_irqsave(&priv->tx_free_list[qos].lock, flags);
107			while (skb_to_free > 0) {
108				struct sk_buff *t;
109
110				t = __skb_dequeue(&priv->tx_free_list[qos]);
111				t->next = to_free_list;
112				to_free_list = t;
113				skb_to_free--;
114			}
115			spin_unlock_irqrestore(&priv->tx_free_list[qos].lock,
116					       flags);
117			/* Do the actual freeing outside of the lock. */
118			while (to_free_list) {
119				struct sk_buff *t = to_free_list;
120
121				to_free_list = to_free_list->next;
122				dev_kfree_skb_any(t);
123			}
124		}
125		total_remaining += skb_queue_len(&priv->tx_free_list[qos]);
126	}
127	if (total_remaining < MAX_OUT_QUEUE_DEPTH && netif_queue_stopped(dev))
128		netif_wake_queue(dev);
129	if (total_remaining)
130		cvm_oct_kick_tx_poll_watchdog();
131}
132
133/**
134 * cvm_oct_xmit - transmit a packet
135 * @skb:    Packet to send
136 * @dev:    Device info structure
137 *
138 * Returns Always returns NETDEV_TX_OK
139 */
140int cvm_oct_xmit(struct sk_buff *skb, struct net_device *dev)
141{
142	cvmx_pko_command_word0_t pko_command;
143	union cvmx_buf_ptr hw_buffer;
144	u64 old_scratch;
145	u64 old_scratch2;
146	int qos;
147	int i;
148	enum {QUEUE_CORE, QUEUE_HW, QUEUE_DROP} queue_type;
149	struct octeon_ethernet *priv = netdev_priv(dev);
150	struct sk_buff *to_free_list;
151	int32_t skb_to_free;
152	int32_t buffers_to_free;
153	u32 total_to_clean;
154	unsigned long flags;
155#if REUSE_SKBUFFS_WITHOUT_FREE
156	unsigned char *fpa_head;
157#endif
158
159	/*
160	 * Prefetch the private data structure.  It is larger than the
161	 * one cache line.
162	 */
163	prefetch(priv);
164
165	/*
166	 * The check on CVMX_PKO_QUEUES_PER_PORT_* is designed to
167	 * completely remove "qos" in the event neither interface
168	 * supports multiple queues per port.
169	 */
170	if ((CVMX_PKO_QUEUES_PER_PORT_INTERFACE0 > 1) ||
171	    (CVMX_PKO_QUEUES_PER_PORT_INTERFACE1 > 1)) {
172		qos = GET_SKBUFF_QOS(skb);
173		if (qos <= 0)
174			qos = 0;
175		else if (qos >= cvmx_pko_get_num_queues(priv->port))
176			qos = 0;
177	} else {
178		qos = 0;
179	}
180
181	if (USE_ASYNC_IOBDMA) {
182		/* Save scratch in case userspace is using it */
183		CVMX_SYNCIOBDMA;
184		old_scratch = cvmx_scratch_read64(CVMX_SCR_SCRATCH);
185		old_scratch2 = cvmx_scratch_read64(CVMX_SCR_SCRATCH + 8);
186
187		/*
188		 * Fetch and increment the number of packets to be
189		 * freed.
190		 */
191		cvmx_fau_async_fetch_and_add32(CVMX_SCR_SCRATCH + 8,
192					       FAU_NUM_PACKET_BUFFERS_TO_FREE,
193					       0);
194		cvmx_fau_async_fetch_and_add32(CVMX_SCR_SCRATCH,
195					       priv->fau + qos * 4,
196					       MAX_SKB_TO_FREE);
197	}
198
199	/*
200	 * We have space for 6 segment pointers, If there will be more
201	 * than that, we must linearize.
202	 */
203	if (unlikely(skb_shinfo(skb)->nr_frags > 5)) {
204		if (unlikely(__skb_linearize(skb))) {
205			queue_type = QUEUE_DROP;
206			if (USE_ASYNC_IOBDMA) {
207				/*
208				 * Get the number of skbuffs in use
209				 * by the hardware
210				 */
211				CVMX_SYNCIOBDMA;
212				skb_to_free =
213					cvmx_scratch_read64(CVMX_SCR_SCRATCH);
214			} else {
215				/*
216				 * Get the number of skbuffs in use
217				 * by the hardware
218				 */
219				skb_to_free = cvmx_fau_fetch_and_add32(
220					priv->fau + qos * 4, MAX_SKB_TO_FREE);
 
 
221			}
222			skb_to_free = cvm_oct_adjust_skb_to_free(skb_to_free,
223							priv->fau + qos * 4);
 
224			spin_lock_irqsave(&priv->tx_free_list[qos].lock, flags);
225			goto skip_xmit;
226		}
227	}
228
229	/*
230	 * The CN3XXX series of parts has an errata (GMX-401) which
231	 * causes the GMX block to hang if a collision occurs towards
232	 * the end of a <68 byte packet. As a workaround for this, we
233	 * pad packets to be 68 bytes whenever we are in half duplex
234	 * mode. We don't handle the case of having a small packet but
235	 * no room to add the padding.  The kernel should always give
236	 * us at least a cache line
237	 */
238	if ((skb->len < 64) && OCTEON_IS_MODEL(OCTEON_CN3XXX)) {
239		union cvmx_gmxx_prtx_cfg gmx_prt_cfg;
240		int interface = INTERFACE(priv->port);
241		int index = INDEX(priv->port);
242
243		if (interface < 2) {
244			/* We only need to pad packet in half duplex mode */
245			gmx_prt_cfg.u64 =
246			    cvmx_read_csr(CVMX_GMXX_PRTX_CFG(index, interface));
247			if (gmx_prt_cfg.s.duplex == 0) {
248				int add_bytes = 64 - skb->len;
249
250				if ((skb_tail_pointer(skb) + add_bytes) <=
251				    skb_end_pointer(skb))
252					memset(__skb_put(skb, add_bytes), 0,
253					       add_bytes);
254			}
255		}
256	}
257
258	/* Build the PKO command */
259	pko_command.u64 = 0;
260#ifdef __LITTLE_ENDIAN
261	pko_command.s.le = 1;
262#endif
263	pko_command.s.n2 = 1;	/* Don't pollute L2 with the outgoing packet */
264	pko_command.s.segs = 1;
265	pko_command.s.total_bytes = skb->len;
266	pko_command.s.size0 = CVMX_FAU_OP_SIZE_32;
267	pko_command.s.subone0 = 1;
268
269	pko_command.s.dontfree = 1;
270
271	/* Build the PKO buffer pointer */
272	hw_buffer.u64 = 0;
273	if (skb_shinfo(skb)->nr_frags == 0) {
274		hw_buffer.s.addr = XKPHYS_TO_PHYS((u64)skb->data);
275		hw_buffer.s.pool = 0;
276		hw_buffer.s.size = skb->len;
277	} else {
278		hw_buffer.s.addr = XKPHYS_TO_PHYS((u64)skb->data);
279		hw_buffer.s.pool = 0;
280		hw_buffer.s.size = skb_headlen(skb);
281		CVM_OCT_SKB_CB(skb)[0] = hw_buffer.u64;
282		for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
283			struct skb_frag_struct *fs = skb_shinfo(skb)->frags + i;
284
285			hw_buffer.s.addr = XKPHYS_TO_PHYS(
286				(u64)(page_address(fs->page.p) +
287				fs->page_offset));
288			hw_buffer.s.size = fs->size;
289			CVM_OCT_SKB_CB(skb)[i + 1] = hw_buffer.u64;
290		}
291		hw_buffer.s.addr = XKPHYS_TO_PHYS((u64)CVM_OCT_SKB_CB(skb));
 
292		hw_buffer.s.size = skb_shinfo(skb)->nr_frags + 1;
293		pko_command.s.segs = skb_shinfo(skb)->nr_frags + 1;
294		pko_command.s.gather = 1;
295		goto dont_put_skbuff_in_hw;
296	}
297
298	/*
299	 * See if we can put this skb in the FPA pool. Any strange
300	 * behavior from the Linux networking stack will most likely
301	 * be caused by a bug in the following code. If some field is
302	 * in use by the network stack and gets carried over when a
303	 * buffer is reused, bad things may happen.  If in doubt and
304	 * you dont need the absolute best performance, disable the
305	 * define REUSE_SKBUFFS_WITHOUT_FREE. The reuse of buffers has
306	 * shown a 25% increase in performance under some loads.
307	 */
308#if REUSE_SKBUFFS_WITHOUT_FREE
309	fpa_head = skb->head + 256 - ((unsigned long)skb->head & 0x7f);
310	if (unlikely(skb->data < fpa_head)) {
311		/* TX buffer beginning can't meet FPA alignment constraints */
312		goto dont_put_skbuff_in_hw;
313	}
314	if (unlikely
315	    ((skb_end_pointer(skb) - fpa_head) < CVMX_FPA_PACKET_POOL_SIZE)) {
316		/* TX buffer isn't large enough for the FPA */
317		goto dont_put_skbuff_in_hw;
318	}
319	if (unlikely(skb_shared(skb))) {
320		/* TX buffer sharing data with someone else */
321		goto dont_put_skbuff_in_hw;
322	}
323	if (unlikely(skb_cloned(skb))) {
324		/* TX buffer has been cloned */
325		goto dont_put_skbuff_in_hw;
326	}
327	if (unlikely(skb_header_cloned(skb))) {
328		/* TX buffer header has been cloned */
329		goto dont_put_skbuff_in_hw;
330	}
331	if (unlikely(skb->destructor)) {
332		/* TX buffer has a destructor */
333		goto dont_put_skbuff_in_hw;
334	}
335	if (unlikely(skb_shinfo(skb)->nr_frags)) {
336		/* TX buffer has fragments */
337		goto dont_put_skbuff_in_hw;
338	}
339	if (unlikely
340	    (skb->truesize !=
341	     sizeof(*skb) + skb_end_offset(skb))) {
342		/* TX buffer truesize has been changed */
343		goto dont_put_skbuff_in_hw;
344	}
345
346	/*
347	 * We can use this buffer in the FPA.  We don't need the FAU
348	 * update anymore
349	 */
350	pko_command.s.dontfree = 0;
351
352	hw_buffer.s.back = ((unsigned long)skb->data >> 7) -
353			   ((unsigned long)fpa_head >> 7);
354
355	*(struct sk_buff **)(fpa_head - sizeof(void *)) = skb;
356
357	/*
358	 * The skbuff will be reused without ever being freed. We must
359	 * cleanup a bunch of core things.
360	 */
361	dst_release(skb_dst(skb));
362	skb_dst_set(skb, NULL);
363#ifdef CONFIG_XFRM
364	secpath_put(skb->sp);
365	skb->sp = NULL;
366#endif
367	nf_reset(skb);
368
369#ifdef CONFIG_NET_SCHED
370	skb->tc_index = 0;
371#ifdef CONFIG_NET_CLS_ACT
372	skb->tc_verd = 0;
373#endif /* CONFIG_NET_CLS_ACT */
374#endif /* CONFIG_NET_SCHED */
375#endif /* REUSE_SKBUFFS_WITHOUT_FREE */
376
377dont_put_skbuff_in_hw:
378
379	/* Check if we can use the hardware checksumming */
380	if ((skb->protocol == htons(ETH_P_IP)) &&
381	    (ip_hdr(skb)->version == 4) &&
382	    (ip_hdr(skb)->ihl == 5) &&
383	    ((ip_hdr(skb)->frag_off == 0) ||
384	     (ip_hdr(skb)->frag_off == htons(1 << 14))) &&
385	    ((ip_hdr(skb)->protocol == IPPROTO_TCP) ||
386	     (ip_hdr(skb)->protocol == IPPROTO_UDP))) {
387		/* Use hardware checksum calc */
388		pko_command.s.ipoffp1 = skb_network_offset(skb) + 1;
389	}
390
391	if (USE_ASYNC_IOBDMA) {
392		/* Get the number of skbuffs in use by the hardware */
393		CVMX_SYNCIOBDMA;
394		skb_to_free = cvmx_scratch_read64(CVMX_SCR_SCRATCH);
395		buffers_to_free = cvmx_scratch_read64(CVMX_SCR_SCRATCH + 8);
396	} else {
397		/* Get the number of skbuffs in use by the hardware */
398		skb_to_free = cvmx_fau_fetch_and_add32(priv->fau + qos * 4,
399						       MAX_SKB_TO_FREE);
400		buffers_to_free =
401		    cvmx_fau_fetch_and_add32(FAU_NUM_PACKET_BUFFERS_TO_FREE, 0);
402	}
403
404	skb_to_free = cvm_oct_adjust_skb_to_free(skb_to_free,
405						priv->fau + qos * 4);
406
407	/*
408	 * If we're sending faster than the receive can free them then
409	 * don't do the HW free.
410	 */
411	if ((buffers_to_free < -100) && !pko_command.s.dontfree)
412		pko_command.s.dontfree = 1;
413
414	if (pko_command.s.dontfree) {
415		queue_type = QUEUE_CORE;
416		pko_command.s.reg0 = priv->fau + qos * 4;
417	} else {
418		queue_type = QUEUE_HW;
419	}
420	if (USE_ASYNC_IOBDMA)
421		cvmx_fau_async_fetch_and_add32(
422				CVMX_SCR_SCRATCH, FAU_TOTAL_TX_TO_CLEAN, 1);
423
424	spin_lock_irqsave(&priv->tx_free_list[qos].lock, flags);
425
426	/* Drop this packet if we have too many already queued to the HW */
427	if (unlikely(skb_queue_len(&priv->tx_free_list[qos]) >=
428		     MAX_OUT_QUEUE_DEPTH)) {
429		if (dev->tx_queue_len != 0) {
430			/* Drop the lock when notifying the core.  */
431			spin_unlock_irqrestore(&priv->tx_free_list[qos].lock,
432					       flags);
433			netif_stop_queue(dev);
434			spin_lock_irqsave(&priv->tx_free_list[qos].lock,
435					  flags);
436		} else {
437			/* If not using normal queueing.  */
438			queue_type = QUEUE_DROP;
439			goto skip_xmit;
440		}
441	}
442
443	cvmx_pko_send_packet_prepare(priv->port, priv->queue + qos,
444				     CVMX_PKO_LOCK_NONE);
445
446	/* Send the packet to the output queue */
447	if (unlikely(cvmx_pko_send_packet_finish(priv->port,
448						 priv->queue + qos,
449						 pko_command, hw_buffer,
450						 CVMX_PKO_LOCK_NONE))) {
451		printk_ratelimited("%s: Failed to send the packet\n",
452				   dev->name);
453		queue_type = QUEUE_DROP;
454	}
455skip_xmit:
456	to_free_list = NULL;
457
458	switch (queue_type) {
459	case QUEUE_DROP:
460		skb->next = to_free_list;
461		to_free_list = skb;
462		priv->stats.tx_dropped++;
463		break;
464	case QUEUE_HW:
465		cvmx_fau_atomic_add32(FAU_NUM_PACKET_BUFFERS_TO_FREE, -1);
466		break;
467	case QUEUE_CORE:
468		__skb_queue_tail(&priv->tx_free_list[qos], skb);
469		break;
470	default:
471		BUG();
472	}
473
474	while (skb_to_free > 0) {
475		struct sk_buff *t = __skb_dequeue(&priv->tx_free_list[qos]);
476
477		t->next = to_free_list;
478		to_free_list = t;
479		skb_to_free--;
480	}
481
482	spin_unlock_irqrestore(&priv->tx_free_list[qos].lock, flags);
483
484	/* Do the actual freeing outside of the lock. */
485	while (to_free_list) {
486		struct sk_buff *t = to_free_list;
487
488		to_free_list = to_free_list->next;
489		dev_kfree_skb_any(t);
490	}
491
492	if (USE_ASYNC_IOBDMA) {
493		CVMX_SYNCIOBDMA;
494		total_to_clean = cvmx_scratch_read64(CVMX_SCR_SCRATCH);
495		/* Restore the scratch area */
496		cvmx_scratch_write64(CVMX_SCR_SCRATCH, old_scratch);
497		cvmx_scratch_write64(CVMX_SCR_SCRATCH + 8, old_scratch2);
498	} else {
499		total_to_clean = cvmx_fau_fetch_and_add32(
500						FAU_TOTAL_TX_TO_CLEAN, 1);
501	}
502
503	if (total_to_clean & 0x3ff) {
504		/*
505		 * Schedule the cleanup tasklet every 1024 packets for
506		 * the pathological case of high traffic on one port
507		 * delaying clean up of packets on a different port
508		 * that is blocked waiting for the cleanup.
509		 */
510		tasklet_schedule(&cvm_oct_tx_cleanup_tasklet);
511	}
512
513	cvm_oct_kick_tx_poll_watchdog();
514
515	return NETDEV_TX_OK;
516}
517
518/**
519 * cvm_oct_xmit_pow - transmit a packet to the POW
520 * @skb:    Packet to send
521 * @dev:    Device info structure
522
523 * Returns Always returns zero
524 */
525int cvm_oct_xmit_pow(struct sk_buff *skb, struct net_device *dev)
526{
527	struct octeon_ethernet *priv = netdev_priv(dev);
528	void *packet_buffer;
529	void *copy_location;
530
531	/* Get a work queue entry */
532	cvmx_wqe_t *work = cvmx_fpa_alloc(CVMX_FPA_WQE_POOL);
533
534	if (unlikely(!work)) {
535		printk_ratelimited("%s: Failed to allocate a work queue entry\n",
536				   dev->name);
537		priv->stats.tx_dropped++;
538		dev_kfree_skb_any(skb);
539		return 0;
540	}
541
542	/* Get a packet buffer */
543	packet_buffer = cvmx_fpa_alloc(CVMX_FPA_PACKET_POOL);
544	if (unlikely(!packet_buffer)) {
545		printk_ratelimited("%s: Failed to allocate a packet buffer\n",
546				   dev->name);
547		cvmx_fpa_free(work, CVMX_FPA_WQE_POOL, 1);
548		priv->stats.tx_dropped++;
549		dev_kfree_skb_any(skb);
550		return 0;
551	}
552
553	/*
554	 * Calculate where we need to copy the data to. We need to
555	 * leave 8 bytes for a next pointer (unused). We also need to
556	 * include any configure skip. Then we need to align the IP
557	 * packet src and dest into the same 64bit word. The below
558	 * calculation may add a little extra, but that doesn't
559	 * hurt.
560	 */
561	copy_location = packet_buffer + sizeof(u64);
562	copy_location += ((CVMX_HELPER_FIRST_MBUFF_SKIP + 7) & 0xfff8) + 6;
563
564	/*
565	 * We have to copy the packet since whoever processes this
566	 * packet will free it to a hardware pool. We can't use the
567	 * trick of counting outstanding packets like in
568	 * cvm_oct_xmit.
569	 */
570	memcpy(copy_location, skb->data, skb->len);
571
572	/*
573	 * Fill in some of the work queue fields. We may need to add
574	 * more if the software at the other end needs them.
575	 */
576	if (!OCTEON_IS_MODEL(OCTEON_CN68XX))
577		work->word0.pip.cn38xx.hw_chksum = skb->csum;
578	work->word1.len = skb->len;
579	cvmx_wqe_set_port(work, priv->port);
580	cvmx_wqe_set_qos(work, priv->port & 0x7);
581	cvmx_wqe_set_grp(work, pow_send_group);
582	work->word1.tag_type = CVMX_HELPER_INPUT_TAG_TYPE;
583	work->word1.tag = pow_send_group;	/* FIXME */
584	/* Default to zero. Sets of zero later are commented out */
585	work->word2.u64 = 0;
586	work->word2.s.bufs = 1;
587	work->packet_ptr.u64 = 0;
588	work->packet_ptr.s.addr = cvmx_ptr_to_phys(copy_location);
589	work->packet_ptr.s.pool = CVMX_FPA_PACKET_POOL;
590	work->packet_ptr.s.size = CVMX_FPA_PACKET_POOL_SIZE;
591	work->packet_ptr.s.back = (copy_location - packet_buffer) >> 7;
592
593	if (skb->protocol == htons(ETH_P_IP)) {
594		work->word2.s.ip_offset = 14;
595#if 0
596		work->word2.s.vlan_valid = 0;	/* FIXME */
597		work->word2.s.vlan_cfi = 0;	/* FIXME */
598		work->word2.s.vlan_id = 0;	/* FIXME */
599		work->word2.s.dec_ipcomp = 0;	/* FIXME */
600#endif
601		work->word2.s.tcp_or_udp =
602		    (ip_hdr(skb)->protocol == IPPROTO_TCP) ||
603		    (ip_hdr(skb)->protocol == IPPROTO_UDP);
604#if 0
605		/* FIXME */
606		work->word2.s.dec_ipsec = 0;
607		/* We only support IPv4 right now */
608		work->word2.s.is_v6 = 0;
609		/* Hardware would set to zero */
610		work->word2.s.software = 0;
611		/* No error, packet is internal */
612		work->word2.s.L4_error = 0;
613#endif
614		work->word2.s.is_frag = !((ip_hdr(skb)->frag_off == 0) ||
615					  (ip_hdr(skb)->frag_off ==
616					      1 << 14));
617#if 0
618		/* Assume Linux is sending a good packet */
619		work->word2.s.IP_exc = 0;
620#endif
621		work->word2.s.is_bcast = (skb->pkt_type == PACKET_BROADCAST);
622		work->word2.s.is_mcast = (skb->pkt_type == PACKET_MULTICAST);
623#if 0
624		/* This is an IP packet */
625		work->word2.s.not_IP = 0;
626		/* No error, packet is internal */
627		work->word2.s.rcv_error = 0;
628		/* No error, packet is internal */
629		work->word2.s.err_code = 0;
630#endif
631
632		/*
633		 * When copying the data, include 4 bytes of the
634		 * ethernet header to align the same way hardware
635		 * does.
636		 */
637		memcpy(work->packet_data, skb->data + 10,
638		       sizeof(work->packet_data));
639	} else {
640#if 0
641		work->word2.snoip.vlan_valid = 0;	/* FIXME */
642		work->word2.snoip.vlan_cfi = 0;	/* FIXME */
643		work->word2.snoip.vlan_id = 0;	/* FIXME */
644		work->word2.snoip.software = 0;	/* Hardware would set to zero */
645#endif
646		work->word2.snoip.is_rarp = skb->protocol == htons(ETH_P_RARP);
647		work->word2.snoip.is_arp = skb->protocol == htons(ETH_P_ARP);
648		work->word2.snoip.is_bcast =
649		    (skb->pkt_type == PACKET_BROADCAST);
650		work->word2.snoip.is_mcast =
651		    (skb->pkt_type == PACKET_MULTICAST);
652		work->word2.snoip.not_IP = 1;	/* IP was done up above */
653#if 0
654		/* No error, packet is internal */
655		work->word2.snoip.rcv_error = 0;
656		/* No error, packet is internal */
657		work->word2.snoip.err_code = 0;
658#endif
659		memcpy(work->packet_data, skb->data, sizeof(work->packet_data));
660	}
661
662	/* Submit the packet to the POW */
663	cvmx_pow_work_submit(work, work->word1.tag, work->word1.tag_type,
664			     cvmx_wqe_get_qos(work), cvmx_wqe_get_grp(work));
665	priv->stats.tx_packets++;
666	priv->stats.tx_bytes += skb->len;
667	dev_consume_skb_any(skb);
668	return 0;
669}
670
671/**
672 * cvm_oct_tx_shutdown_dev - free all skb that are currently queued for TX.
673 * @dev:    Device being shutdown
674 *
675 */
676void cvm_oct_tx_shutdown_dev(struct net_device *dev)
677{
678	struct octeon_ethernet *priv = netdev_priv(dev);
679	unsigned long flags;
680	int qos;
681
682	for (qos = 0; qos < 16; qos++) {
683		spin_lock_irqsave(&priv->tx_free_list[qos].lock, flags);
684		while (skb_queue_len(&priv->tx_free_list[qos]))
685			dev_kfree_skb_any(__skb_dequeue
686					  (&priv->tx_free_list[qos]));
687		spin_unlock_irqrestore(&priv->tx_free_list[qos].lock, flags);
688	}
689}
690
691static void cvm_oct_tx_do_cleanup(unsigned long arg)
692{
693	int port;
694
695	for (port = 0; port < TOTAL_NUMBER_OF_PORTS; port++) {
696		if (cvm_oct_device[port]) {
697			struct net_device *dev = cvm_oct_device[port];
698
699			cvm_oct_free_tx_skbs(dev);
700		}
701	}
702}
703
704static irqreturn_t cvm_oct_tx_cleanup_watchdog(int cpl, void *dev_id)
705{
706	/* Disable the interrupt.  */
707	cvmx_write_csr(CVMX_CIU_TIMX(1), 0);
708	/* Do the work in the tasklet.  */
709	tasklet_schedule(&cvm_oct_tx_cleanup_tasklet);
710	return IRQ_HANDLED;
711}
712
713void cvm_oct_tx_initialize(void)
714{
715	int i;
716
717	/* Disable the interrupt.  */
718	cvmx_write_csr(CVMX_CIU_TIMX(1), 0);
719	/* Register an IRQ handler to receive CIU_TIMX(1) interrupts */
720	i = request_irq(OCTEON_IRQ_TIMER1,
721			cvm_oct_tx_cleanup_watchdog, 0,
722			"Ethernet", cvm_oct_device);
723
724	if (i)
725		panic("Could not acquire Ethernet IRQ %d\n", OCTEON_IRQ_TIMER1);
726}
727
728void cvm_oct_tx_shutdown(void)
729{
730	/* Free the interrupt handler */
731	free_irq(OCTEON_IRQ_TIMER1, cvm_oct_device);
732}
v6.9.4
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * This file is based on code from OCTEON SDK by Cavium Networks.
  4 *
  5 * Copyright (c) 2003-2010 Cavium Networks
 
 
 
 
  6 */
  7
  8#include <linux/module.h>
  9#include <linux/kernel.h>
 10#include <linux/netdevice.h>
 11#include <linux/etherdevice.h>
 12#include <linux/ip.h>
 13#include <linux/ratelimit.h>
 14#include <linux/string.h>
 15#include <linux/interrupt.h>
 16#include <net/dst.h>
 17#ifdef CONFIG_XFRM
 18#include <linux/xfrm.h>
 19#include <net/xfrm.h>
 20#endif /* CONFIG_XFRM */
 21
 22#include <linux/atomic.h>
 23#include <net/sch_generic.h>
 24
 
 
 
 25#include "octeon-ethernet.h"
 26#include "ethernet-defines.h"
 27#include "ethernet-tx.h"
 28#include "ethernet-util.h"
 29
 
 
 
 
 
 
 
 
 30#define CVM_OCT_SKB_CB(skb)	((u64 *)((skb)->cb))
 31
 32/*
 33 * You can define GET_SKBUFF_QOS() to override how the skbuff output
 34 * function determines which output queue is used. The default
 35 * implementation always uses the base queue for the port. If, for
 36 * example, you wanted to use the skb->priority field, define
 37 * GET_SKBUFF_QOS as: #define GET_SKBUFF_QOS(skb) ((skb)->priority)
 38 */
 39#ifndef GET_SKBUFF_QOS
 40#define GET_SKBUFF_QOS(skb) 0
 41#endif
 42
 43static void cvm_oct_tx_do_cleanup(unsigned long arg);
 44static DECLARE_TASKLET_OLD(cvm_oct_tx_cleanup_tasklet, cvm_oct_tx_do_cleanup);
 45
 46/* Maximum number of SKBs to try to free per xmit packet. */
 47#define MAX_SKB_TO_FREE (MAX_OUT_QUEUE_DEPTH * 2)
 48
 49static inline int cvm_oct_adjust_skb_to_free(int skb_to_free, int fau)
 50{
 51	int undo;
 52
 53	undo = skb_to_free > 0 ? MAX_SKB_TO_FREE : skb_to_free +
 54						   MAX_SKB_TO_FREE;
 55	if (undo > 0)
 56		cvmx_fau_atomic_add32(fau, -undo);
 57	skb_to_free = -skb_to_free > MAX_SKB_TO_FREE ? MAX_SKB_TO_FREE :
 58						       -skb_to_free;
 59	return skb_to_free;
 60}
 61
 62static void cvm_oct_kick_tx_poll_watchdog(void)
 63{
 64	union cvmx_ciu_timx ciu_timx;
 65
 66	ciu_timx.u64 = 0;
 67	ciu_timx.s.one_shot = 1;
 68	ciu_timx.s.len = cvm_oct_tx_poll_interval;
 69	cvmx_write_csr(CVMX_CIU_TIMX(1), ciu_timx.u64);
 70}
 71
 72static void cvm_oct_free_tx_skbs(struct net_device *dev)
 73{
 74	int skb_to_free;
 75	int qos, queues_per_port;
 
 76	int total_remaining = 0;
 77	unsigned long flags;
 78	struct octeon_ethernet *priv = netdev_priv(dev);
 79
 80	queues_per_port = cvmx_pko_get_num_queues(priv->port);
 81	/* Drain any pending packets in the free list */
 82	for (qos = 0; qos < queues_per_port; qos++) {
 83		if (skb_queue_len(&priv->tx_free_list[qos]) == 0)
 84			continue;
 85		skb_to_free = cvmx_fau_fetch_and_add32(priv->fau + qos * 4,
 86						       MAX_SKB_TO_FREE);
 87		skb_to_free = cvm_oct_adjust_skb_to_free(skb_to_free,
 88							 priv->fau + qos * 4);
 
 89		if (skb_to_free > 0) {
 90			struct sk_buff *to_free_list = NULL;
 91
 92			spin_lock_irqsave(&priv->tx_free_list[qos].lock, flags);
 93			while (skb_to_free > 0) {
 94				struct sk_buff *t;
 95
 96				t = __skb_dequeue(&priv->tx_free_list[qos]);
 97				t->next = to_free_list;
 98				to_free_list = t;
 99				skb_to_free--;
100			}
101			spin_unlock_irqrestore(&priv->tx_free_list[qos].lock,
102					       flags);
103			/* Do the actual freeing outside of the lock. */
104			while (to_free_list) {
105				struct sk_buff *t = to_free_list;
106
107				to_free_list = to_free_list->next;
108				dev_kfree_skb_any(t);
109			}
110		}
111		total_remaining += skb_queue_len(&priv->tx_free_list[qos]);
112	}
113	if (total_remaining < MAX_OUT_QUEUE_DEPTH && netif_queue_stopped(dev))
114		netif_wake_queue(dev);
115	if (total_remaining)
116		cvm_oct_kick_tx_poll_watchdog();
117}
118
119/**
120 * cvm_oct_xmit - transmit a packet
121 * @skb:    Packet to send
122 * @dev:    Device info structure
123 *
124 * Returns Always returns NETDEV_TX_OK
125 */
126netdev_tx_t cvm_oct_xmit(struct sk_buff *skb, struct net_device *dev)
127{
128	union cvmx_pko_command_word0 pko_command;
129	union cvmx_buf_ptr hw_buffer;
130	u64 old_scratch;
131	u64 old_scratch2;
132	int qos;
133	int i;
134	enum {QUEUE_CORE, QUEUE_HW, QUEUE_DROP} queue_type;
135	struct octeon_ethernet *priv = netdev_priv(dev);
136	struct sk_buff *to_free_list;
137	int skb_to_free;
138	int buffers_to_free;
139	u32 total_to_clean;
140	unsigned long flags;
141#if REUSE_SKBUFFS_WITHOUT_FREE
142	unsigned char *fpa_head;
143#endif
144
145	/*
146	 * Prefetch the private data structure.  It is larger than the
147	 * one cache line.
148	 */
149	prefetch(priv);
150
151	/*
152	 * The check on CVMX_PKO_QUEUES_PER_PORT_* is designed to
153	 * completely remove "qos" in the event neither interface
154	 * supports multiple queues per port.
155	 */
156	if ((CVMX_PKO_QUEUES_PER_PORT_INTERFACE0 > 1) ||
157	    (CVMX_PKO_QUEUES_PER_PORT_INTERFACE1 > 1)) {
158		qos = GET_SKBUFF_QOS(skb);
159		if (qos <= 0)
160			qos = 0;
161		else if (qos >= cvmx_pko_get_num_queues(priv->port))
162			qos = 0;
163	} else {
164		qos = 0;
165	}
166
167	if (USE_ASYNC_IOBDMA) {
168		/* Save scratch in case userspace is using it */
169		CVMX_SYNCIOBDMA;
170		old_scratch = cvmx_scratch_read64(CVMX_SCR_SCRATCH);
171		old_scratch2 = cvmx_scratch_read64(CVMX_SCR_SCRATCH + 8);
172
173		/*
174		 * Fetch and increment the number of packets to be
175		 * freed.
176		 */
177		cvmx_fau_async_fetch_and_add32(CVMX_SCR_SCRATCH + 8,
178					       FAU_NUM_PACKET_BUFFERS_TO_FREE,
179					       0);
180		cvmx_fau_async_fetch_and_add32(CVMX_SCR_SCRATCH,
181					       priv->fau + qos * 4,
182					       MAX_SKB_TO_FREE);
183	}
184
185	/*
186	 * We have space for 6 segment pointers, If there will be more
187	 * than that, we must linearize.
188	 */
189	if (unlikely(skb_shinfo(skb)->nr_frags > 5)) {
190		if (unlikely(__skb_linearize(skb))) {
191			queue_type = QUEUE_DROP;
192			if (USE_ASYNC_IOBDMA) {
193				/*
194				 * Get the number of skbuffs in use
195				 * by the hardware
196				 */
197				CVMX_SYNCIOBDMA;
198				skb_to_free =
199					cvmx_scratch_read64(CVMX_SCR_SCRATCH);
200			} else {
201				/*
202				 * Get the number of skbuffs in use
203				 * by the hardware
204				 */
205				skb_to_free =
206				     cvmx_fau_fetch_and_add32(priv->fau +
207							      qos * 4,
208							      MAX_SKB_TO_FREE);
209			}
210			skb_to_free = cvm_oct_adjust_skb_to_free(skb_to_free,
211								 priv->fau +
212								 qos * 4);
213			spin_lock_irqsave(&priv->tx_free_list[qos].lock, flags);
214			goto skip_xmit;
215		}
216	}
217
218	/*
219	 * The CN3XXX series of parts has an errata (GMX-401) which
220	 * causes the GMX block to hang if a collision occurs towards
221	 * the end of a <68 byte packet. As a workaround for this, we
222	 * pad packets to be 68 bytes whenever we are in half duplex
223	 * mode. We don't handle the case of having a small packet but
224	 * no room to add the padding.  The kernel should always give
225	 * us at least a cache line
226	 */
227	if ((skb->len < 64) && OCTEON_IS_MODEL(OCTEON_CN3XXX)) {
228		union cvmx_gmxx_prtx_cfg gmx_prt_cfg;
229		int interface = INTERFACE(priv->port);
230		int index = INDEX(priv->port);
231
232		if (interface < 2) {
233			/* We only need to pad packet in half duplex mode */
234			gmx_prt_cfg.u64 =
235			    cvmx_read_csr(CVMX_GMXX_PRTX_CFG(index, interface));
236			if (gmx_prt_cfg.s.duplex == 0) {
237				int add_bytes = 64 - skb->len;
238
239				if ((skb_tail_pointer(skb) + add_bytes) <=
240				    skb_end_pointer(skb))
241					__skb_put_zero(skb, add_bytes);
 
242			}
243		}
244	}
245
246	/* Build the PKO command */
247	pko_command.u64 = 0;
248#ifdef __LITTLE_ENDIAN
249	pko_command.s.le = 1;
250#endif
251	pko_command.s.n2 = 1;	/* Don't pollute L2 with the outgoing packet */
252	pko_command.s.segs = 1;
253	pko_command.s.total_bytes = skb->len;
254	pko_command.s.size0 = CVMX_FAU_OP_SIZE_32;
255	pko_command.s.subone0 = 1;
256
257	pko_command.s.dontfree = 1;
258
259	/* Build the PKO buffer pointer */
260	hw_buffer.u64 = 0;
261	if (skb_shinfo(skb)->nr_frags == 0) {
262		hw_buffer.s.addr = XKPHYS_TO_PHYS((uintptr_t)skb->data);
263		hw_buffer.s.pool = 0;
264		hw_buffer.s.size = skb->len;
265	} else {
266		hw_buffer.s.addr = XKPHYS_TO_PHYS((uintptr_t)skb->data);
267		hw_buffer.s.pool = 0;
268		hw_buffer.s.size = skb_headlen(skb);
269		CVM_OCT_SKB_CB(skb)[0] = hw_buffer.u64;
270		for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
271			skb_frag_t *fs = skb_shinfo(skb)->frags + i;
272
273			hw_buffer.s.addr =
274				XKPHYS_TO_PHYS((uintptr_t)skb_frag_address(fs));
275			hw_buffer.s.size = skb_frag_size(fs);
 
276			CVM_OCT_SKB_CB(skb)[i + 1] = hw_buffer.u64;
277		}
278		hw_buffer.s.addr =
279			XKPHYS_TO_PHYS((uintptr_t)CVM_OCT_SKB_CB(skb));
280		hw_buffer.s.size = skb_shinfo(skb)->nr_frags + 1;
281		pko_command.s.segs = skb_shinfo(skb)->nr_frags + 1;
282		pko_command.s.gather = 1;
283		goto dont_put_skbuff_in_hw;
284	}
285
286	/*
287	 * See if we can put this skb in the FPA pool. Any strange
288	 * behavior from the Linux networking stack will most likely
289	 * be caused by a bug in the following code. If some field is
290	 * in use by the network stack and gets carried over when a
291	 * buffer is reused, bad things may happen.  If in doubt and
292	 * you dont need the absolute best performance, disable the
293	 * define REUSE_SKBUFFS_WITHOUT_FREE. The reuse of buffers has
294	 * shown a 25% increase in performance under some loads.
295	 */
296#if REUSE_SKBUFFS_WITHOUT_FREE
297	fpa_head = skb->head + 256 - ((unsigned long)skb->head & 0x7f);
298	if (unlikely(skb->data < fpa_head)) {
299		/* TX buffer beginning can't meet FPA alignment constraints */
300		goto dont_put_skbuff_in_hw;
301	}
302	if (unlikely
303	    ((skb_end_pointer(skb) - fpa_head) < CVMX_FPA_PACKET_POOL_SIZE)) {
304		/* TX buffer isn't large enough for the FPA */
305		goto dont_put_skbuff_in_hw;
306	}
307	if (unlikely(skb_shared(skb))) {
308		/* TX buffer sharing data with someone else */
309		goto dont_put_skbuff_in_hw;
310	}
311	if (unlikely(skb_cloned(skb))) {
312		/* TX buffer has been cloned */
313		goto dont_put_skbuff_in_hw;
314	}
315	if (unlikely(skb_header_cloned(skb))) {
316		/* TX buffer header has been cloned */
317		goto dont_put_skbuff_in_hw;
318	}
319	if (unlikely(skb->destructor)) {
320		/* TX buffer has a destructor */
321		goto dont_put_skbuff_in_hw;
322	}
323	if (unlikely(skb_shinfo(skb)->nr_frags)) {
324		/* TX buffer has fragments */
325		goto dont_put_skbuff_in_hw;
326	}
327	if (unlikely
328	    (skb->truesize !=
329	     sizeof(*skb) + skb_end_offset(skb))) {
330		/* TX buffer truesize has been changed */
331		goto dont_put_skbuff_in_hw;
332	}
333
334	/*
335	 * We can use this buffer in the FPA.  We don't need the FAU
336	 * update anymore
337	 */
338	pko_command.s.dontfree = 0;
339
340	hw_buffer.s.back = ((unsigned long)skb->data >> 7) -
341			   ((unsigned long)fpa_head >> 7);
342
343	*(struct sk_buff **)(fpa_head - sizeof(void *)) = skb;
344
345	/*
346	 * The skbuff will be reused without ever being freed. We must
347	 * cleanup a bunch of core things.
348	 */
349	dst_release(skb_dst(skb));
350	skb_dst_set(skb, NULL);
351	skb_ext_reset(skb);
352	nf_reset_ct(skb);
353	skb_reset_redirect(skb);
 
 
354
355#ifdef CONFIG_NET_SCHED
356	skb->tc_index = 0;
 
 
 
357#endif /* CONFIG_NET_SCHED */
358#endif /* REUSE_SKBUFFS_WITHOUT_FREE */
359
360dont_put_skbuff_in_hw:
361
362	/* Check if we can use the hardware checksumming */
363	if ((skb->protocol == htons(ETH_P_IP)) &&
364	    (ip_hdr(skb)->version == 4) &&
365	    (ip_hdr(skb)->ihl == 5) &&
366	    ((ip_hdr(skb)->frag_off == 0) ||
367	     (ip_hdr(skb)->frag_off == htons(1 << 14))) &&
368	    ((ip_hdr(skb)->protocol == IPPROTO_TCP) ||
369	     (ip_hdr(skb)->protocol == IPPROTO_UDP))) {
370		/* Use hardware checksum calc */
371		pko_command.s.ipoffp1 = skb_network_offset(skb) + 1;
372	}
373
374	if (USE_ASYNC_IOBDMA) {
375		/* Get the number of skbuffs in use by the hardware */
376		CVMX_SYNCIOBDMA;
377		skb_to_free = cvmx_scratch_read64(CVMX_SCR_SCRATCH);
378		buffers_to_free = cvmx_scratch_read64(CVMX_SCR_SCRATCH + 8);
379	} else {
380		/* Get the number of skbuffs in use by the hardware */
381		skb_to_free = cvmx_fau_fetch_and_add32(priv->fau + qos * 4,
382						       MAX_SKB_TO_FREE);
383		buffers_to_free =
384		    cvmx_fau_fetch_and_add32(FAU_NUM_PACKET_BUFFERS_TO_FREE, 0);
385	}
386
387	skb_to_free = cvm_oct_adjust_skb_to_free(skb_to_free,
388						 priv->fau + qos * 4);
389
390	/*
391	 * If we're sending faster than the receive can free them then
392	 * don't do the HW free.
393	 */
394	if ((buffers_to_free < -100) && !pko_command.s.dontfree)
395		pko_command.s.dontfree = 1;
396
397	if (pko_command.s.dontfree) {
398		queue_type = QUEUE_CORE;
399		pko_command.s.reg0 = priv->fau + qos * 4;
400	} else {
401		queue_type = QUEUE_HW;
402	}
403	if (USE_ASYNC_IOBDMA)
404		cvmx_fau_async_fetch_and_add32(CVMX_SCR_SCRATCH,
405					       FAU_TOTAL_TX_TO_CLEAN, 1);
406
407	spin_lock_irqsave(&priv->tx_free_list[qos].lock, flags);
408
409	/* Drop this packet if we have too many already queued to the HW */
410	if (unlikely(skb_queue_len(&priv->tx_free_list[qos]) >=
411		     MAX_OUT_QUEUE_DEPTH)) {
412		if (dev->tx_queue_len != 0) {
413			/* Drop the lock when notifying the core.  */
414			spin_unlock_irqrestore(&priv->tx_free_list[qos].lock,
415					       flags);
416			netif_stop_queue(dev);
417			spin_lock_irqsave(&priv->tx_free_list[qos].lock,
418					  flags);
419		} else {
420			/* If not using normal queueing.  */
421			queue_type = QUEUE_DROP;
422			goto skip_xmit;
423		}
424	}
425
426	cvmx_pko_send_packet_prepare(priv->port, priv->queue + qos,
427				     CVMX_PKO_LOCK_NONE);
428
429	/* Send the packet to the output queue */
430	if (unlikely(cvmx_pko_send_packet_finish(priv->port,
431						 priv->queue + qos,
432						 pko_command, hw_buffer,
433						 CVMX_PKO_LOCK_NONE))) {
434		printk_ratelimited("%s: Failed to send the packet\n",
435				   dev->name);
436		queue_type = QUEUE_DROP;
437	}
438skip_xmit:
439	to_free_list = NULL;
440
441	switch (queue_type) {
442	case QUEUE_DROP:
443		skb->next = to_free_list;
444		to_free_list = skb;
445		dev->stats.tx_dropped++;
446		break;
447	case QUEUE_HW:
448		cvmx_fau_atomic_add32(FAU_NUM_PACKET_BUFFERS_TO_FREE, -1);
449		break;
450	case QUEUE_CORE:
451		__skb_queue_tail(&priv->tx_free_list[qos], skb);
452		break;
453	default:
454		BUG();
455	}
456
457	while (skb_to_free > 0) {
458		struct sk_buff *t = __skb_dequeue(&priv->tx_free_list[qos]);
459
460		t->next = to_free_list;
461		to_free_list = t;
462		skb_to_free--;
463	}
464
465	spin_unlock_irqrestore(&priv->tx_free_list[qos].lock, flags);
466
467	/* Do the actual freeing outside of the lock. */
468	while (to_free_list) {
469		struct sk_buff *t = to_free_list;
470
471		to_free_list = to_free_list->next;
472		dev_kfree_skb_any(t);
473	}
474
475	if (USE_ASYNC_IOBDMA) {
476		CVMX_SYNCIOBDMA;
477		total_to_clean = cvmx_scratch_read64(CVMX_SCR_SCRATCH);
478		/* Restore the scratch area */
479		cvmx_scratch_write64(CVMX_SCR_SCRATCH, old_scratch);
480		cvmx_scratch_write64(CVMX_SCR_SCRATCH + 8, old_scratch2);
481	} else {
482		total_to_clean =
483			cvmx_fau_fetch_and_add32(FAU_TOTAL_TX_TO_CLEAN, 1);
484	}
485
486	if (total_to_clean & 0x3ff) {
487		/*
488		 * Schedule the cleanup tasklet every 1024 packets for
489		 * the pathological case of high traffic on one port
490		 * delaying clean up of packets on a different port
491		 * that is blocked waiting for the cleanup.
492		 */
493		tasklet_schedule(&cvm_oct_tx_cleanup_tasklet);
494	}
495
496	cvm_oct_kick_tx_poll_watchdog();
497
498	return NETDEV_TX_OK;
499}
500
501/**
502 * cvm_oct_xmit_pow - transmit a packet to the POW
503 * @skb:    Packet to send
504 * @dev:    Device info structure
 
505 * Returns Always returns zero
506 */
507netdev_tx_t cvm_oct_xmit_pow(struct sk_buff *skb, struct net_device *dev)
508{
509	struct octeon_ethernet *priv = netdev_priv(dev);
510	void *packet_buffer;
511	void *copy_location;
512
513	/* Get a work queue entry */
514	struct cvmx_wqe *work = cvmx_fpa_alloc(CVMX_FPA_WQE_POOL);
515
516	if (unlikely(!work)) {
517		printk_ratelimited("%s: Failed to allocate a work queue entry\n",
518				   dev->name);
519		dev->stats.tx_dropped++;
520		dev_kfree_skb_any(skb);
521		return 0;
522	}
523
524	/* Get a packet buffer */
525	packet_buffer = cvmx_fpa_alloc(CVMX_FPA_PACKET_POOL);
526	if (unlikely(!packet_buffer)) {
527		printk_ratelimited("%s: Failed to allocate a packet buffer\n",
528				   dev->name);
529		cvmx_fpa_free(work, CVMX_FPA_WQE_POOL, 1);
530		dev->stats.tx_dropped++;
531		dev_kfree_skb_any(skb);
532		return 0;
533	}
534
535	/*
536	 * Calculate where we need to copy the data to. We need to
537	 * leave 8 bytes for a next pointer (unused). We also need to
538	 * include any configure skip. Then we need to align the IP
539	 * packet src and dest into the same 64bit word. The below
540	 * calculation may add a little extra, but that doesn't
541	 * hurt.
542	 */
543	copy_location = packet_buffer + sizeof(u64);
544	copy_location += ((CVMX_HELPER_FIRST_MBUFF_SKIP + 7) & 0xfff8) + 6;
545
546	/*
547	 * We have to copy the packet since whoever processes this
548	 * packet will free it to a hardware pool. We can't use the
549	 * trick of counting outstanding packets like in
550	 * cvm_oct_xmit.
551	 */
552	memcpy(copy_location, skb->data, skb->len);
553
554	/*
555	 * Fill in some of the work queue fields. We may need to add
556	 * more if the software at the other end needs them.
557	 */
558	if (!OCTEON_IS_MODEL(OCTEON_CN68XX))
559		work->word0.pip.cn38xx.hw_chksum = skb->csum;
560	work->word1.len = skb->len;
561	cvmx_wqe_set_port(work, priv->port);
562	cvmx_wqe_set_qos(work, priv->port & 0x7);
563	cvmx_wqe_set_grp(work, pow_send_group);
564	work->word1.tag_type = CVMX_HELPER_INPUT_TAG_TYPE;
565	work->word1.tag = pow_send_group;	/* FIXME */
566	/* Default to zero. Sets of zero later are commented out */
567	work->word2.u64 = 0;
568	work->word2.s.bufs = 1;
569	work->packet_ptr.u64 = 0;
570	work->packet_ptr.s.addr = cvmx_ptr_to_phys(copy_location);
571	work->packet_ptr.s.pool = CVMX_FPA_PACKET_POOL;
572	work->packet_ptr.s.size = CVMX_FPA_PACKET_POOL_SIZE;
573	work->packet_ptr.s.back = (copy_location - packet_buffer) >> 7;
574
575	if (skb->protocol == htons(ETH_P_IP)) {
576		work->word2.s.ip_offset = 14;
577#if 0
578		work->word2.s.vlan_valid = 0;	/* FIXME */
579		work->word2.s.vlan_cfi = 0;	/* FIXME */
580		work->word2.s.vlan_id = 0;	/* FIXME */
581		work->word2.s.dec_ipcomp = 0;	/* FIXME */
582#endif
583		work->word2.s.tcp_or_udp =
584		    (ip_hdr(skb)->protocol == IPPROTO_TCP) ||
585		    (ip_hdr(skb)->protocol == IPPROTO_UDP);
586#if 0
587		/* FIXME */
588		work->word2.s.dec_ipsec = 0;
589		/* We only support IPv4 right now */
590		work->word2.s.is_v6 = 0;
591		/* Hardware would set to zero */
592		work->word2.s.software = 0;
593		/* No error, packet is internal */
594		work->word2.s.L4_error = 0;
595#endif
596		work->word2.s.is_frag = !((ip_hdr(skb)->frag_off == 0) ||
597					  (ip_hdr(skb)->frag_off ==
598					      cpu_to_be16(1 << 14)));
599#if 0
600		/* Assume Linux is sending a good packet */
601		work->word2.s.IP_exc = 0;
602#endif
603		work->word2.s.is_bcast = (skb->pkt_type == PACKET_BROADCAST);
604		work->word2.s.is_mcast = (skb->pkt_type == PACKET_MULTICAST);
605#if 0
606		/* This is an IP packet */
607		work->word2.s.not_IP = 0;
608		/* No error, packet is internal */
609		work->word2.s.rcv_error = 0;
610		/* No error, packet is internal */
611		work->word2.s.err_code = 0;
612#endif
613
614		/*
615		 * When copying the data, include 4 bytes of the
616		 * ethernet header to align the same way hardware
617		 * does.
618		 */
619		memcpy(work->packet_data, skb->data + 10,
620		       sizeof(work->packet_data));
621	} else {
622#if 0
623		work->word2.snoip.vlan_valid = 0;	/* FIXME */
624		work->word2.snoip.vlan_cfi = 0;	/* FIXME */
625		work->word2.snoip.vlan_id = 0;	/* FIXME */
626		work->word2.snoip.software = 0;	/* Hardware would set to zero */
627#endif
628		work->word2.snoip.is_rarp = skb->protocol == htons(ETH_P_RARP);
629		work->word2.snoip.is_arp = skb->protocol == htons(ETH_P_ARP);
630		work->word2.snoip.is_bcast =
631		    (skb->pkt_type == PACKET_BROADCAST);
632		work->word2.snoip.is_mcast =
633		    (skb->pkt_type == PACKET_MULTICAST);
634		work->word2.snoip.not_IP = 1;	/* IP was done up above */
635#if 0
636		/* No error, packet is internal */
637		work->word2.snoip.rcv_error = 0;
638		/* No error, packet is internal */
639		work->word2.snoip.err_code = 0;
640#endif
641		memcpy(work->packet_data, skb->data, sizeof(work->packet_data));
642	}
643
644	/* Submit the packet to the POW */
645	cvmx_pow_work_submit(work, work->word1.tag, work->word1.tag_type,
646			     cvmx_wqe_get_qos(work), cvmx_wqe_get_grp(work));
647	dev->stats.tx_packets++;
648	dev->stats.tx_bytes += skb->len;
649	dev_consume_skb_any(skb);
650	return 0;
651}
652
653/**
654 * cvm_oct_tx_shutdown_dev - free all skb that are currently queued for TX.
655 * @dev:    Device being shutdown
656 *
657 */
658void cvm_oct_tx_shutdown_dev(struct net_device *dev)
659{
660	struct octeon_ethernet *priv = netdev_priv(dev);
661	unsigned long flags;
662	int qos;
663
664	for (qos = 0; qos < 16; qos++) {
665		spin_lock_irqsave(&priv->tx_free_list[qos].lock, flags);
666		while (skb_queue_len(&priv->tx_free_list[qos]))
667			dev_kfree_skb_any(__skb_dequeue
668					  (&priv->tx_free_list[qos]));
669		spin_unlock_irqrestore(&priv->tx_free_list[qos].lock, flags);
670	}
671}
672
673static void cvm_oct_tx_do_cleanup(unsigned long arg)
674{
675	int port;
676
677	for (port = 0; port < TOTAL_NUMBER_OF_PORTS; port++) {
678		if (cvm_oct_device[port]) {
679			struct net_device *dev = cvm_oct_device[port];
680
681			cvm_oct_free_tx_skbs(dev);
682		}
683	}
684}
685
686static irqreturn_t cvm_oct_tx_cleanup_watchdog(int cpl, void *dev_id)
687{
688	/* Disable the interrupt.  */
689	cvmx_write_csr(CVMX_CIU_TIMX(1), 0);
690	/* Do the work in the tasklet.  */
691	tasklet_schedule(&cvm_oct_tx_cleanup_tasklet);
692	return IRQ_HANDLED;
693}
694
695void cvm_oct_tx_initialize(void)
696{
697	int i;
698
699	/* Disable the interrupt.  */
700	cvmx_write_csr(CVMX_CIU_TIMX(1), 0);
701	/* Register an IRQ handler to receive CIU_TIMX(1) interrupts */
702	i = request_irq(OCTEON_IRQ_TIMER1,
703			cvm_oct_tx_cleanup_watchdog, 0,
704			"Ethernet", cvm_oct_device);
705
706	if (i)
707		panic("Could not acquire Ethernet IRQ %d\n", OCTEON_IRQ_TIMER1);
708}
709
710void cvm_oct_tx_shutdown(void)
711{
712	/* Free the interrupt handler */
713	free_irq(OCTEON_IRQ_TIMER1, cvm_oct_device);
714}