2 * This file is based on code from OCTEON SDK by Cavium Networks.
4 * Copyright (c) 2003-2010 Cavium Networks
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.
11 #include <linux/module.h>
12 #include <linux/kernel.h>
13 #include <linux/cache.h>
14 #include <linux/cpumask.h>
15 #include <linux/netdevice.h>
16 #include <linux/etherdevice.h>
18 #include <linux/string.h>
19 #include <linux/prefetch.h>
20 #include <linux/ratelimit.h>
21 #include <linux/smp.h>
22 #include <linux/interrupt.h>
25 #include <linux/xfrm.h>
27 #endif /* CONFIG_XFRM */
29 #include <linux/atomic.h>
31 #include <asm/octeon/octeon.h>
33 #include "ethernet-defines.h"
34 #include "ethernet-mem.h"
35 #include "ethernet-rx.h"
36 #include "octeon-ethernet.h"
37 #include "ethernet-util.h"
39 #include <asm/octeon/cvmx-helper.h>
40 #include <asm/octeon/cvmx-wqe.h>
41 #include <asm/octeon/cvmx-fau.h>
42 #include <asm/octeon/cvmx-pow.h>
43 #include <asm/octeon/cvmx-pip.h>
44 #include <asm/octeon/cvmx-scratch.h>
46 #include <asm/octeon/cvmx-gmxx-defs.h>
48 static struct napi_struct cvm_oct_napi;
51 * cvm_oct_do_interrupt - interrupt handler.
53 * The interrupt occurs whenever the POW has packets in our group.
56 static irqreturn_t cvm_oct_do_interrupt(int cpl, void *dev_id)
58 /* Disable the IRQ and start napi_poll. */
59 disable_irq_nosync(OCTEON_IRQ_WORKQ0 + pow_receive_group);
60 napi_schedule(&cvm_oct_napi);
66 * cvm_oct_check_rcv_error - process receive errors
67 * @work: Work queue entry pointing to the packet.
69 * Returns Non-zero if the packet can be dropped, zero otherwise.
71 static inline int cvm_oct_check_rcv_error(cvmx_wqe_t *work)
75 if (octeon_has_feature(OCTEON_FEATURE_PKND))
76 port = work->word0.pip.cn68xx.pknd;
78 port = work->word1.cn38xx.ipprt;
80 if ((work->word2.snoip.err_code == 10) && (work->word1.len <= 64)) {
82 * Ignore length errors on min size packets. Some
83 * equipment incorrectly pads packets to 64+4FCS
84 * instead of 60+4FCS. Note these packets still get
85 * counted as frame errors.
87 } else if (work->word2.snoip.err_code == 5 ||
88 work->word2.snoip.err_code == 7) {
90 * We received a packet with either an alignment error
91 * or a FCS error. This may be signalling that we are
92 * running 10Mbps with GMXX_RXX_FRM_CTL[PRE_CHK]
93 * off. If this is the case we need to parse the
94 * packet to determine if we can remove a non spec
95 * preamble and generate a correct packet.
97 int interface = cvmx_helper_get_interface_num(port);
98 int index = cvmx_helper_get_interface_index_num(port);
99 union cvmx_gmxx_rxx_frm_ctl gmxx_rxx_frm_ctl;
101 gmxx_rxx_frm_ctl.u64 =
102 cvmx_read_csr(CVMX_GMXX_RXX_FRM_CTL(index, interface));
103 if (gmxx_rxx_frm_ctl.s.pre_chk == 0) {
106 cvmx_phys_to_ptr(work->packet_ptr.s.addr);
109 while (i < work->word1.len - 1) {
118 printk_ratelimited("Port %d received 0xd5 preamble\n",
121 work->packet_ptr.s.addr += i + 1;
122 work->word1.len -= i + 5;
123 } else if ((*ptr & 0xf) == 0xd) {
125 printk_ratelimited("Port %d received 0x?d preamble\n",
128 work->packet_ptr.s.addr += i;
129 work->word1.len -= i + 4;
130 for (i = 0; i < work->word1.len; i++) {
132 ((*ptr & 0xf0) >> 4) |
133 ((*(ptr + 1) & 0xf) << 4);
137 printk_ratelimited("Port %d unknown preamble, packet dropped\n",
140 cvmx_helper_dump_packet(work);
142 cvm_oct_free_work(work);
147 printk_ratelimited("Port %d receive error code %d, packet dropped\n",
148 port, work->word2.snoip.err_code);
149 cvm_oct_free_work(work);
157 * cvm_oct_napi_poll - the NAPI poll function.
158 * @napi: The NAPI instance, or null if called from cvm_oct_poll_controller
159 * @budget: Maximum number of packets to receive.
161 * Returns the number of packets processed.
163 static int cvm_oct_napi_poll(struct napi_struct *napi, int budget)
165 const int coreid = cvmx_get_core_num();
166 uint64_t old_group_mask;
167 uint64_t old_scratch;
169 int did_work_request = 0;
170 int packet_not_copied;
172 /* Prefetch cvm_oct_device since we know we need it soon */
173 prefetch(cvm_oct_device);
175 if (USE_ASYNC_IOBDMA) {
176 /* Save scratch in case userspace is using it */
178 old_scratch = cvmx_scratch_read64(CVMX_SCR_SCRATCH);
181 /* Only allow work for our group (and preserve priorities) */
182 if (OCTEON_IS_MODEL(OCTEON_CN68XX)) {
183 old_group_mask = cvmx_read_csr(CVMX_SSO_PPX_GRP_MSK(coreid));
184 cvmx_write_csr(CVMX_SSO_PPX_GRP_MSK(coreid),
185 1ull << pow_receive_group);
186 cvmx_read_csr(CVMX_SSO_PPX_GRP_MSK(coreid)); /* Flush */
188 old_group_mask = cvmx_read_csr(CVMX_POW_PP_GRP_MSKX(coreid));
189 cvmx_write_csr(CVMX_POW_PP_GRP_MSKX(coreid),
190 (old_group_mask & ~0xFFFFull) | 1 << pow_receive_group);
193 if (USE_ASYNC_IOBDMA) {
194 cvmx_pow_work_request_async(CVMX_SCR_SCRATCH, CVMX_POW_NO_WAIT);
195 did_work_request = 1;
198 while (rx_count < budget) {
199 struct sk_buff *skb = NULL;
200 struct sk_buff **pskb = NULL;
205 if (USE_ASYNC_IOBDMA && did_work_request)
206 work = cvmx_pow_work_response_async(CVMX_SCR_SCRATCH);
208 work = cvmx_pow_work_request_sync(CVMX_POW_NO_WAIT);
211 did_work_request = 0;
213 if (OCTEON_IS_MODEL(OCTEON_CN68XX)) {
214 cvmx_write_csr(CVMX_SSO_WQ_IQ_DIS,
215 1ull << pow_receive_group);
216 cvmx_write_csr(CVMX_SSO_WQ_INT,
217 1ull << pow_receive_group);
219 union cvmx_pow_wq_int wq_int;
222 wq_int.s.iq_dis = 1 << pow_receive_group;
223 wq_int.s.wq_int = 1 << pow_receive_group;
224 cvmx_write_csr(CVMX_POW_WQ_INT, wq_int.u64);
228 pskb = (struct sk_buff **)(cvm_oct_get_buffer_ptr(work->packet_ptr) -
232 if (USE_ASYNC_IOBDMA && rx_count < (budget - 1)) {
233 cvmx_pow_work_request_async_nocheck(CVMX_SCR_SCRATCH,
235 did_work_request = 1;
239 skb_in_hw = work->word2.s.bufs == 1;
240 if (likely(skb_in_hw)) {
242 prefetch(&skb->head);
246 if (octeon_has_feature(OCTEON_FEATURE_PKND))
247 port = work->word0.pip.cn68xx.pknd;
249 port = work->word1.cn38xx.ipprt;
251 prefetch(cvm_oct_device[port]);
253 /* Immediately throw away all packets with receive errors */
254 if (unlikely(work->word2.snoip.rcv_error)) {
255 if (cvm_oct_check_rcv_error(work))
260 * We can only use the zero copy path if skbuffs are
261 * in the FPA pool and the packet fits in a single
264 if (likely(skb_in_hw)) {
265 skb->data = skb->head + work->packet_ptr.s.addr -
266 cvmx_ptr_to_phys(skb->head);
268 skb->len = work->word1.len;
269 skb_set_tail_pointer(skb, skb->len);
270 packet_not_copied = 1;
273 * We have to copy the packet. First allocate
276 skb = dev_alloc_skb(work->word1.len);
278 cvm_oct_free_work(work);
283 * Check if we've received a packet that was
284 * entirely stored in the work entry.
286 if (unlikely(work->word2.s.bufs == 0)) {
287 uint8_t *ptr = work->packet_data;
289 if (likely(!work->word2.s.not_IP)) {
291 * The beginning of the packet
292 * moves for IP packets.
294 if (work->word2.s.is_v6)
299 memcpy(skb_put(skb, work->word1.len), ptr,
301 /* No packet buffers to free */
303 int segments = work->word2.s.bufs;
304 union cvmx_buf_ptr segment_ptr =
306 int len = work->word1.len;
309 union cvmx_buf_ptr next_ptr =
310 *(union cvmx_buf_ptr *)cvmx_phys_to_ptr(segment_ptr.s.addr - 8);
313 * Octeon Errata PKI-100: The segment size is
314 * wrong. Until it is fixed, calculate the
315 * segment size based on the packet pool
316 * buffer size. When it is fixed, the
317 * following line should be replaced with this
318 * one: int segment_size =
319 * segment_ptr.s.size;
322 CVMX_FPA_PACKET_POOL_SIZE -
323 (segment_ptr.s.addr -
324 (((segment_ptr.s.addr >> 7) -
325 segment_ptr.s.back) << 7));
327 * Don't copy more than what
328 * is left in the packet.
330 if (segment_size > len)
332 /* Copy the data into the packet */
333 memcpy(skb_put(skb, segment_size),
334 cvmx_phys_to_ptr(segment_ptr.s.addr),
337 segment_ptr = next_ptr;
340 packet_not_copied = 0;
342 if (likely((port < TOTAL_NUMBER_OF_PORTS) &&
343 cvm_oct_device[port])) {
344 struct net_device *dev = cvm_oct_device[port];
345 struct octeon_ethernet *priv = netdev_priv(dev);
348 * Only accept packets for devices that are
351 if (likely(dev->flags & IFF_UP)) {
352 skb->protocol = eth_type_trans(skb, dev);
355 if (unlikely(work->word2.s.not_IP ||
356 work->word2.s.IP_exc ||
357 work->word2.s.L4_error ||
358 !work->word2.s.tcp_or_udp))
359 skb->ip_summed = CHECKSUM_NONE;
361 skb->ip_summed = CHECKSUM_UNNECESSARY;
363 /* Increment RX stats for virtual ports */
364 if (port >= CVMX_PIP_NUM_INPUT_PORTS) {
367 (atomic64_t *)&priv->stats.rx_packets);
368 atomic64_add(skb->len,
369 (atomic64_t *)&priv->stats.rx_bytes);
372 (atomic_t *)&priv->stats.rx_packets);
374 (atomic_t *)&priv->stats.rx_bytes);
377 netif_receive_skb(skb);
379 /* Drop any packet received for a device that isn't up */
381 printk_ratelimited("%s: Device not up, packet dropped\n",
386 (atomic64_t *)&priv->stats.rx_dropped);
389 (atomic_t *)&priv->stats.rx_dropped);
391 dev_kfree_skb_irq(skb);
395 * Drop any packet received for a device that
398 printk_ratelimited("Port %d not controlled by Linux, packet dropped\n",
400 dev_kfree_skb_irq(skb);
403 * Check to see if the skbuff and work share the same
406 if (likely(packet_not_copied)) {
408 * This buffer needs to be replaced, increment
409 * the number of buffers we need to free by
412 cvmx_fau_atomic_add32(FAU_NUM_PACKET_BUFFERS_TO_FREE,
415 cvmx_fpa_free(work, CVMX_FPA_WQE_POOL, 1);
417 cvm_oct_free_work(work);
420 /* Restore the original POW group mask */
421 if (OCTEON_IS_MODEL(OCTEON_CN68XX)) {
422 cvmx_write_csr(CVMX_SSO_PPX_GRP_MSK(coreid), old_group_mask);
423 cvmx_read_csr(CVMX_SSO_PPX_GRP_MSK(coreid)); /* Flush */
425 cvmx_write_csr(CVMX_POW_PP_GRP_MSKX(coreid), old_group_mask);
428 if (USE_ASYNC_IOBDMA) {
429 /* Restore the scratch area */
430 cvmx_scratch_write64(CVMX_SCR_SCRATCH, old_scratch);
432 cvm_oct_rx_refill_pool(0);
434 if (rx_count < budget && napi != NULL) {
437 enable_irq(OCTEON_IRQ_WORKQ0 + pow_receive_group);
442 #ifdef CONFIG_NET_POLL_CONTROLLER
444 * cvm_oct_poll_controller - poll for receive packets
447 * @dev: Device to poll. Unused
449 void cvm_oct_poll_controller(struct net_device *dev)
451 cvm_oct_napi_poll(NULL, 16);
455 void cvm_oct_rx_initialize(void)
458 struct net_device *dev_for_napi = NULL;
460 for (i = 0; i < TOTAL_NUMBER_OF_PORTS; i++) {
461 if (cvm_oct_device[i]) {
462 dev_for_napi = cvm_oct_device[i];
467 if (NULL == dev_for_napi)
468 panic("No net_devices were allocated.");
470 netif_napi_add(dev_for_napi, &cvm_oct_napi, cvm_oct_napi_poll,
472 napi_enable(&cvm_oct_napi);
474 /* Register an IRQ handler to receive POW interrupts */
475 i = request_irq(OCTEON_IRQ_WORKQ0 + pow_receive_group,
476 cvm_oct_do_interrupt, 0, "Ethernet", cvm_oct_device);
479 panic("Could not acquire Ethernet IRQ %d\n",
480 OCTEON_IRQ_WORKQ0 + pow_receive_group);
482 disable_irq_nosync(OCTEON_IRQ_WORKQ0 + pow_receive_group);
484 /* Enable POW interrupt when our port has at least one packet */
485 if (OCTEON_IS_MODEL(OCTEON_CN68XX)) {
486 union cvmx_sso_wq_int_thrx int_thr;
487 union cvmx_pow_wq_int_pc int_pc;
491 int_thr.s.tc_thr = 1;
492 cvmx_write_csr(CVMX_SSO_WQ_INT_THRX(pow_receive_group),
497 cvmx_write_csr(CVMX_SSO_WQ_INT_PC, int_pc.u64);
499 union cvmx_pow_wq_int_thrx int_thr;
500 union cvmx_pow_wq_int_pc int_pc;
504 int_thr.s.tc_thr = 1;
505 cvmx_write_csr(CVMX_POW_WQ_INT_THRX(pow_receive_group),
510 cvmx_write_csr(CVMX_POW_WQ_INT_PC, int_pc.u64);
513 /* Schedule NAPI now. This will indirectly enable the interrupt. */
514 napi_schedule(&cvm_oct_napi);
517 void cvm_oct_rx_shutdown(void)
519 netif_napi_del(&cvm_oct_napi);