xref: /titanic_41/usr/src/uts/common/io/bge/bge_recv2.c (revision 6be356c5780a1ccb886bba08d6eb56b61f021564)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 #include "sys/bge_impl2.h"
30 
31 #define	U32TOPTR(x)	((void *)(uintptr_t)(uint32_t)(x))
32 #define	PTRTOU32(x)	((uint32_t)(uintptr_t)(void *)(x))
33 
34 /*
35  * ========== RX side routines ==========
36  */
37 
38 #define	BGE_DBG		BGE_DBG_RECV	/* debug flag for this code	*/
39 
40 static void bge_refill(bge_t *bgep, buff_ring_t *brp, sw_rbd_t *srbdp);
41 #pragma	inline(bge_refill)
42 
43 /*
44  * Return the specified buffer (srbdp) to the ring it came from (brp).
45  *
46  * Note:
47  *	If the driver is compiled with only one buffer ring *and* one
48  *	return ring, then the buffers must be returned in sequence.
49  *	In this case, we don't have to consider anything about the
50  *	buffer at all; we can simply advance the cyclic counter.  And
51  *	we don't even need the refill mutex <rf_lock>, as the caller
52  *	will already be holding the (one-and-only) <rx_lock>.
53  *
54  *	If the driver supports multiple buffer rings, but only one
55  *	return ring, the same still applies (to each buffer ring
56  *	separately).
57  */
58 static void
59 bge_refill(bge_t *bgep, buff_ring_t *brp, sw_rbd_t *srbdp)
60 {
61 	uint64_t slot;
62 
63 	_NOTE(ARGUNUSED(srbdp))
64 
65 	slot = brp->rf_next;
66 	brp->rf_next = NEXT(slot, brp->desc.nslots);
67 	bge_mbx_put(bgep, brp->chip_mbx_reg, slot);
68 }
69 
70 static mblk_t *bge_receive_packet(bge_t *bgep, bge_rbd_t *hw_rbd_p);
71 #pragma	inline(bge_receive_packet)
72 
73 static mblk_t *
74 bge_receive_packet(bge_t *bgep, bge_rbd_t *hw_rbd_p)
75 {
76 	bge_rbd_t hw_rbd;
77 	buff_ring_t *brp;
78 	sw_rbd_t *srbdp;
79 	uchar_t *dp;
80 	mblk_t *mp;
81 	uint_t len;
82 	uint_t minsize;
83 	uint_t maxsize;
84 	uint32_t pflags;
85 
86 	mp = NULL;
87 	hw_rbd = *hw_rbd_p;
88 
89 	switch (hw_rbd.flags & (RBD_FLAG_MINI_RING|RBD_FLAG_JUMBO_RING)) {
90 	case RBD_FLAG_MINI_RING|RBD_FLAG_JUMBO_RING:
91 	default:
92 		/* error, this shouldn't happen */
93 		BGE_PKTDUMP((bgep, &hw_rbd, NULL, "bad ring flags!"));
94 		goto error;
95 
96 	case RBD_FLAG_JUMBO_RING:
97 		brp = &bgep->buff[BGE_JUMBO_BUFF_RING];
98 		break;
99 
100 #if	(BGE_BUFF_RINGS_USED > 2)
101 	case RBD_FLAG_MINI_RING:
102 		brp = &bgep->buff[BGE_MINI_BUFF_RING];
103 		break;
104 #endif	/* BGE_BUFF_RINGS_USED > 2 */
105 
106 	case 0:
107 		brp = &bgep->buff[BGE_STD_BUFF_RING];
108 		break;
109 	}
110 
111 	if (hw_rbd.index >= brp->desc.nslots) {
112 		/* error, this shouldn't happen */
113 		BGE_PKTDUMP((bgep, &hw_rbd, NULL, "bad ring index!"));
114 		goto error;
115 	}
116 
117 	srbdp = &brp->sw_rbds[hw_rbd.index];
118 	if (hw_rbd.opaque != srbdp->pbuf.token) {
119 		/* bogus, drop the packet */
120 		BGE_PKTDUMP((bgep, &hw_rbd, srbdp, "bad ring token"));
121 		goto refill;
122 	}
123 
124 	if ((hw_rbd.flags & RBD_FLAG_PACKET_END) == 0) {
125 		/* bogus, drop the packet */
126 		BGE_PKTDUMP((bgep, &hw_rbd, srbdp, "unterminated packet"));
127 		goto refill;
128 	}
129 
130 	if (hw_rbd.flags & RBD_FLAG_FRAME_HAS_ERROR) {
131 		/* bogus, drop the packet */
132 		BGE_PKTDUMP((bgep, &hw_rbd, srbdp, "errored packet"));
133 		goto refill;
134 	}
135 
136 	len = hw_rbd.len;
137 
138 	/*
139 	 * H/W will not strip the VLAN tag from incoming packet now, as
140 	 * RECEIVE_MODE_KEEP_VLAN_TAG bit is set in RECEIVE_MAC_MODE_REG
141 	 * register.
142 	 */
143 	maxsize = bgep->chipid.ethmax_size + VLAN_TAGSZ + ETHERFCSL;
144 	if (len > maxsize) {
145 		/* bogus, drop the packet */
146 		BGE_PKTDUMP((bgep, &hw_rbd, srbdp, "oversize packet"));
147 		goto refill;
148 	}
149 
150 	minsize = ETHERMIN + ETHERFCSL;
151 	if (len < minsize) {
152 		/* bogus, drop the packet */
153 		BGE_PKTDUMP((bgep, &hw_rbd, srbdp, "undersize packet"));
154 		goto refill;
155 	}
156 
157 	/*
158 	 * Packet looks good; get a buffer to copy it into.
159 	 * We want to leave some space at the front of the allocated
160 	 * buffer in case any upstream modules want to prepend some
161 	 * sort of header.  This also has the side-effect of making
162 	 * the packet *contents* 4-byte aligned, as required by NCA!
163 	 */
164 	mp = allocb(BGE_HEADROOM + len, 0);
165 	if (mp == NULL) {
166 		/* Nothing to do but drop the packet */
167 		goto refill;
168 	}
169 
170 	/*
171 	 * Sync the data and copy it to the STREAMS buffer.
172 	 */
173 	DMA_SYNC(srbdp->pbuf, DDI_DMA_SYNC_FORKERNEL);
174 	mp->b_rptr = dp = mp->b_rptr + BGE_HEADROOM;
175 	bcopy(DMA_VPTR(srbdp->pbuf), dp, len);
176 	mp->b_wptr = dp + len - ETHERFCSL;
177 
178 	/*
179 	 * Special check for one specific type of data corruption;
180 	 * in a good packet, the first 8 bytes are *very* unlikely
181 	 * to be the same as the second 8 bytes ... but we let the
182 	 * packet through just in case.
183 	 */
184 	if (bcmp(dp, dp+8, 8) == 0)
185 		BGE_PKTDUMP((bgep, &hw_rbd, srbdp, "stuttered packet?"));
186 
187 	pflags = 0;
188 	if (hw_rbd.flags & RBD_FLAG_TCP_UDP_CHECKSUM)
189 		pflags |= HCK_FULLCKSUM;
190 	if (hw_rbd.flags & RBD_FLAG_IP_CHECKSUM)
191 		pflags |= HCK_IPV4_HDRCKSUM;
192 	if (pflags != 0)
193 		(void) hcksum_assoc(mp, NULL, NULL, 0, 0, 0,
194 		    hw_rbd.tcp_udp_cksum, pflags, 0);
195 
196 refill:
197 	/*
198 	 * Replace the buffer in the ring it came from ...
199 	 */
200 	bge_refill(bgep, brp, srbdp);
201 	return (mp);
202 
203 error:
204 	/*
205 	 * We come here if the integrity of the ring descriptors
206 	 * (rather than merely packet data) appears corrupted.
207 	 * The factotum will attempt to reset-and-recover.
208 	 */
209 	mutex_enter(bgep->genlock);
210 	bgep->bge_chip_state = BGE_CHIP_ERROR;
211 	mutex_exit(bgep->genlock);
212 	return (NULL);
213 }
214 
215 /*
216  * Accept the packets received in the specified ring up to
217  * (but not including) the producer index in the status block.
218  *
219  * Returns a chain of mblks containing the received data, to be
220  * passed up to gld_recv() (we can't call gld_recv() from here,
221  * 'cos we're holding the per-ring receive lock at this point).
222  *
223  * This function must advance (rrp->rx_next) and write it back to
224  * the chip to indicate the packets it has accepted from the ring.
225  */
226 static mblk_t *bge_receive_ring(bge_t *bgep, recv_ring_t *rrp);
227 #pragma	inline(bge_receive_ring)
228 
229 static mblk_t *
230 bge_receive_ring(bge_t *bgep, recv_ring_t *rrp)
231 {
232 	bge_rbd_t *hw_rbd_p;
233 	uint64_t slot;
234 	mblk_t *head;
235 	mblk_t **tail;
236 	mblk_t *mp;
237 
238 	ASSERT(mutex_owned(rrp->rx_lock));
239 
240 	/*
241 	 * Sync (all) the receive ring descriptors
242 	 * before accepting the packets they describe
243 	 */
244 	DMA_SYNC(rrp->desc, DDI_DMA_SYNC_FORKERNEL);
245 	hw_rbd_p = DMA_VPTR(rrp->desc);
246 	head = NULL;
247 	tail = &head;
248 	slot = rrp->rx_next;
249 
250 	while (slot != *rrp->prod_index_p) {	/* Note: volatile	*/
251 		if ((mp = bge_receive_packet(bgep, &hw_rbd_p[slot])) != NULL) {
252 			*tail = mp;
253 			tail = &mp->b_next;
254 		}
255 		rrp->rx_next = slot = NEXT(slot, rrp->desc.nslots);
256 	}
257 
258 	bge_mbx_put(bgep, rrp->chip_mbx_reg, rrp->rx_next);
259 	return (head);
260 }
261 
262 /*
263  * Receive all packets in all rings.
264  *
265  * To give priority to low-numbered rings, whenever we have received any
266  * packets in any ring except 0, we restart scanning again from ring 0.
267  * Thus, for example, if rings 0, 3, and 10 are carrying traffic, the
268  * pattern of receives might go 0, 3, 10, 3, 0, 10, 0:
269  *
270  *	0	found some - receive them
271  *	1..2					none found
272  *	3	found some - receive them	and restart scan
273  *	0..9					none found
274  *	10	found some - receive them	and restart scan
275  *	0..2					none found
276  *	3	found some more - receive them	and restart scan
277  *	0	found some more - receive them
278  *	1..9					none found
279  *	10	found some more - receive them	and restart scan
280  *	0	found some more - receive them
281  *	1..15					none found
282  *
283  * The routine returns only when a complete scan has been performed
284  * without finding any packets to receive.
285  *
286  * Note that driver-defined locks may *NOT* be held across calls
287  * to gld_recv().
288  *
289  * Note: the expression (BGE_RECV_RINGS_USED > 1), yields a compile-time
290  * constant and allows the compiler to optimise away the outer do-loop
291  * if only one receive ring is being used.
292  */
293 void bge_receive(bge_t *bgep, bge_status_t *bsp);
294 #pragma	no_inline(bge_receive)
295 
296 void
297 bge_receive(bge_t *bgep, bge_status_t *bsp)
298 {
299 	recv_ring_t *rrp;
300 	uint64_t ring;
301 	uint64_t rx_rings = bgep->chipid.rx_rings;
302 	mblk_t *mp;
303 
304 restart:
305 	ring = 0;
306 	rrp = &bgep->recv[ring];
307 	do {
308 		/*
309 		 * For each ring, (rrp->prod_index_p) points to the
310 		 * proper index within the status block (which has
311 		 * already been sync'd by the caller)
312 		 */
313 		ASSERT(rrp->prod_index_p == RECV_INDEX_P(bsp, ring));
314 
315 		if (*rrp->prod_index_p == rrp->rx_next)
316 			continue;		/* no packets		*/
317 		if (mutex_tryenter(rrp->rx_lock) == 0)
318 			continue;		/* already in process	*/
319 		mp = bge_receive_ring(bgep, rrp);
320 		mutex_exit(rrp->rx_lock);
321 
322 		if (mp != NULL) {
323 			mac_rx(bgep->macp, rrp->handle, mp);
324 
325 			/*
326 			 * Restart from ring 0, if the driver is compiled
327 			 * with multiple rings and we're not on ring 0 now
328 			 */
329 			if (rx_rings > 1 && ring > 0)
330 				goto restart;
331 		}
332 
333 		/*
334 		 * Loop over all rings (if there *are* multiple rings)
335 		 */
336 	} while (++rrp, ++ring < rx_rings);
337 }
338