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 <asm/octeon/octeon.h>
31 #include "ethernet-defines.h"
32 #include "ethernet-mem.h"
33 #include "ethernet-rx.h"
34 #include "octeon-ethernet.h"
35 #include "ethernet-util.h"
37 #include <asm/octeon/cvmx-helper.h>
38 #include <asm/octeon/cvmx-wqe.h>
39 #include <asm/octeon/cvmx-fau.h>
40 #include <asm/octeon/cvmx-pow.h>
41 #include <asm/octeon/cvmx-pip.h>
42 #include <asm/octeon/cvmx-scratch.h>
44 #include <asm/octeon/cvmx-gmxx-defs.h>
46 static atomic_t oct_rx_ready = ATOMIC_INIT(0);
48 static struct oct_rx_group {
51 struct napi_struct napi;
55 * cvm_oct_do_interrupt - interrupt handler.
56 * @irq: Interrupt number.
57 * @napi_id: Cookie to identify the NAPI instance.
59 * The interrupt occurs whenever the POW has packets in our group.
62 static irqreturn_t cvm_oct_do_interrupt(int irq, void *napi_id)
64 /* Disable the IRQ and start napi_poll. */
65 disable_irq_nosync(irq);
66 napi_schedule(napi_id);
72 * cvm_oct_check_rcv_error - process receive errors
73 * @work: Work queue entry pointing to the packet.
75 * Returns Non-zero if the packet can be dropped, zero otherwise.
77 static inline int cvm_oct_check_rcv_error(cvmx_wqe_t *work)
81 if (octeon_has_feature(OCTEON_FEATURE_PKND))
82 port = work->word0.pip.cn68xx.pknd;
84 port = work->word1.cn38xx.ipprt;
86 if ((work->word2.snoip.err_code == 10) && (work->word1.len <= 64)) {
88 * Ignore length errors on min size packets. Some
89 * equipment incorrectly pads packets to 64+4FCS
90 * instead of 60+4FCS. Note these packets still get
91 * counted as frame errors.
93 } else if (work->word2.snoip.err_code == 5 ||
94 work->word2.snoip.err_code == 7) {
96 * We received a packet with either an alignment error
97 * or a FCS error. This may be signalling that we are
98 * running 10Mbps with GMXX_RXX_FRM_CTL[PRE_CHK]
99 * off. If this is the case we need to parse the
100 * packet to determine if we can remove a non spec
101 * preamble and generate a correct packet.
103 int interface = cvmx_helper_get_interface_num(port);
104 int index = cvmx_helper_get_interface_index_num(port);
105 union cvmx_gmxx_rxx_frm_ctl gmxx_rxx_frm_ctl;
107 gmxx_rxx_frm_ctl.u64 =
108 cvmx_read_csr(CVMX_GMXX_RXX_FRM_CTL(index, interface));
109 if (gmxx_rxx_frm_ctl.s.pre_chk == 0) {
111 cvmx_phys_to_ptr(work->packet_ptr.s.addr);
114 while (i < work->word1.len - 1) {
122 /* Port received 0xd5 preamble */
123 work->packet_ptr.s.addr += i + 1;
124 work->word1.len -= i + 5;
125 } else if ((*ptr & 0xf) == 0xd) {
126 /* Port received 0xd preamble */
127 work->packet_ptr.s.addr += i;
128 work->word1.len -= i + 4;
129 for (i = 0; i < work->word1.len; i++) {
131 ((*ptr & 0xf0) >> 4) |
132 ((*(ptr + 1) & 0xf) << 4);
136 printk_ratelimited("Port %d unknown preamble, packet dropped\n",
138 cvm_oct_free_work(work);
143 printk_ratelimited("Port %d receive error code %d, packet dropped\n",
144 port, work->word2.snoip.err_code);
145 cvm_oct_free_work(work);
152 static int cvm_oct_poll(struct oct_rx_group *rx_group, int budget)
154 const int coreid = cvmx_get_core_num();
158 int did_work_request = 0;
159 int packet_not_copied;
161 /* Prefetch cvm_oct_device since we know we need it soon */
162 prefetch(cvm_oct_device);
164 if (USE_ASYNC_IOBDMA) {
165 /* Save scratch in case userspace is using it */
167 old_scratch = cvmx_scratch_read64(CVMX_SCR_SCRATCH);
170 /* Only allow work for our group (and preserve priorities) */
171 if (OCTEON_IS_MODEL(OCTEON_CN68XX)) {
172 old_group_mask = cvmx_read_csr(CVMX_SSO_PPX_GRP_MSK(coreid));
173 cvmx_write_csr(CVMX_SSO_PPX_GRP_MSK(coreid),
174 BIT(rx_group->group));
175 cvmx_read_csr(CVMX_SSO_PPX_GRP_MSK(coreid)); /* Flush */
177 old_group_mask = cvmx_read_csr(CVMX_POW_PP_GRP_MSKX(coreid));
178 cvmx_write_csr(CVMX_POW_PP_GRP_MSKX(coreid),
179 (old_group_mask & ~0xFFFFull) |
180 BIT(rx_group->group));
183 if (USE_ASYNC_IOBDMA) {
184 cvmx_pow_work_request_async(CVMX_SCR_SCRATCH, CVMX_POW_NO_WAIT);
185 did_work_request = 1;
188 while (rx_count < budget) {
189 struct sk_buff *skb = NULL;
190 struct sk_buff **pskb = NULL;
195 if (USE_ASYNC_IOBDMA && did_work_request)
196 work = cvmx_pow_work_response_async(CVMX_SCR_SCRATCH);
198 work = cvmx_pow_work_request_sync(CVMX_POW_NO_WAIT);
201 did_work_request = 0;
203 if (OCTEON_IS_MODEL(OCTEON_CN68XX)) {
204 cvmx_write_csr(CVMX_SSO_WQ_IQ_DIS,
205 BIT(rx_group->group));
206 cvmx_write_csr(CVMX_SSO_WQ_INT,
207 BIT(rx_group->group));
209 union cvmx_pow_wq_int wq_int;
212 wq_int.s.iq_dis = BIT(rx_group->group);
213 wq_int.s.wq_int = BIT(rx_group->group);
214 cvmx_write_csr(CVMX_POW_WQ_INT, wq_int.u64);
218 pskb = (struct sk_buff **)
219 (cvm_oct_get_buffer_ptr(work->packet_ptr) -
223 if (USE_ASYNC_IOBDMA && rx_count < (budget - 1)) {
224 cvmx_pow_work_request_async_nocheck(CVMX_SCR_SCRATCH,
226 did_work_request = 1;
230 skb_in_hw = work->word2.s.bufs == 1;
231 if (likely(skb_in_hw)) {
233 prefetch(&skb->head);
237 if (octeon_has_feature(OCTEON_FEATURE_PKND))
238 port = work->word0.pip.cn68xx.pknd;
240 port = work->word1.cn38xx.ipprt;
242 prefetch(cvm_oct_device[port]);
244 /* Immediately throw away all packets with receive errors */
245 if (unlikely(work->word2.snoip.rcv_error)) {
246 if (cvm_oct_check_rcv_error(work))
251 * We can only use the zero copy path if skbuffs are
252 * in the FPA pool and the packet fits in a single
255 if (likely(skb_in_hw)) {
256 skb->data = skb->head + work->packet_ptr.s.addr -
257 cvmx_ptr_to_phys(skb->head);
259 skb->len = work->word1.len;
260 skb_set_tail_pointer(skb, skb->len);
261 packet_not_copied = 1;
264 * We have to copy the packet. First allocate
267 skb = dev_alloc_skb(work->word1.len);
269 cvm_oct_free_work(work);
274 * Check if we've received a packet that was
275 * entirely stored in the work entry.
277 if (unlikely(work->word2.s.bufs == 0)) {
278 u8 *ptr = work->packet_data;
280 if (likely(!work->word2.s.not_IP)) {
282 * The beginning of the packet
283 * moves for IP packets.
285 if (work->word2.s.is_v6)
290 memcpy(skb_put(skb, work->word1.len), ptr,
292 /* No packet buffers to free */
294 int segments = work->word2.s.bufs;
295 union cvmx_buf_ptr segment_ptr =
297 int len = work->word1.len;
300 union cvmx_buf_ptr next_ptr =
301 *(union cvmx_buf_ptr *)
303 segment_ptr.s.addr - 8);
306 * Octeon Errata PKI-100: The segment size is
307 * wrong. Until it is fixed, calculate the
308 * segment size based on the packet pool
309 * buffer size. When it is fixed, the
310 * following line should be replaced with this
311 * one: int segment_size =
312 * segment_ptr.s.size;
315 CVMX_FPA_PACKET_POOL_SIZE -
316 (segment_ptr.s.addr -
317 (((segment_ptr.s.addr >> 7) -
318 segment_ptr.s.back) << 7));
320 * Don't copy more than what
321 * is left in the packet.
323 if (segment_size > len)
325 /* Copy the data into the packet */
326 memcpy(skb_put(skb, segment_size),
331 segment_ptr = next_ptr;
334 packet_not_copied = 0;
336 if (likely((port < TOTAL_NUMBER_OF_PORTS) &&
337 cvm_oct_device[port])) {
338 struct net_device *dev = cvm_oct_device[port];
341 * Only accept packets for devices that are
344 if (likely(dev->flags & IFF_UP)) {
345 skb->protocol = eth_type_trans(skb, dev);
348 if (unlikely(work->word2.s.not_IP ||
349 work->word2.s.IP_exc ||
350 work->word2.s.L4_error ||
351 !work->word2.s.tcp_or_udp))
352 skb->ip_summed = CHECKSUM_NONE;
354 skb->ip_summed = CHECKSUM_UNNECESSARY;
356 /* Increment RX stats for virtual ports */
357 if (port >= CVMX_PIP_NUM_INPUT_PORTS) {
358 dev->stats.rx_packets++;
359 dev->stats.rx_bytes += skb->len;
361 netif_receive_skb(skb);
364 * Drop any packet received for a device that
367 dev->stats.rx_dropped++;
368 dev_kfree_skb_irq(skb);
372 * Drop any packet received for a device that
375 printk_ratelimited("Port %d not controlled by Linux, packet dropped\n",
377 dev_kfree_skb_irq(skb);
380 * Check to see if the skbuff and work share the same
383 if (likely(packet_not_copied)) {
385 * This buffer needs to be replaced, increment
386 * the number of buffers we need to free by
389 cvmx_fau_atomic_add32(FAU_NUM_PACKET_BUFFERS_TO_FREE,
392 cvmx_fpa_free(work, CVMX_FPA_WQE_POOL, 1);
394 cvm_oct_free_work(work);
397 /* Restore the original POW group mask */
398 if (OCTEON_IS_MODEL(OCTEON_CN68XX)) {
399 cvmx_write_csr(CVMX_SSO_PPX_GRP_MSK(coreid), old_group_mask);
400 cvmx_read_csr(CVMX_SSO_PPX_GRP_MSK(coreid)); /* Flush */
402 cvmx_write_csr(CVMX_POW_PP_GRP_MSKX(coreid), old_group_mask);
405 if (USE_ASYNC_IOBDMA) {
406 /* Restore the scratch area */
407 cvmx_scratch_write64(CVMX_SCR_SCRATCH, old_scratch);
409 cvm_oct_rx_refill_pool(0);
415 * cvm_oct_napi_poll - the NAPI poll function.
416 * @napi: The NAPI instance.
417 * @budget: Maximum number of packets to receive.
419 * Returns the number of packets processed.
421 static int cvm_oct_napi_poll(struct napi_struct *napi, int budget)
423 struct oct_rx_group *rx_group = container_of(napi, struct oct_rx_group,
427 rx_count = cvm_oct_poll(rx_group, budget);
429 if (rx_count < budget) {
431 napi_complete_done(napi, rx_count);
432 enable_irq(rx_group->irq);
437 #ifdef CONFIG_NET_POLL_CONTROLLER
439 * cvm_oct_poll_controller - poll for receive packets
442 * @dev: Device to poll. Unused
444 void cvm_oct_poll_controller(struct net_device *dev)
448 if (!atomic_read(&oct_rx_ready))
451 for (i = 0; i < ARRAY_SIZE(oct_rx_group); i++) {
452 if (!(pow_receive_groups & BIT(i)))
455 cvm_oct_poll(&oct_rx_group[i], 16);
460 void cvm_oct_rx_initialize(void)
463 struct net_device *dev_for_napi = NULL;
465 for (i = 0; i < TOTAL_NUMBER_OF_PORTS; i++) {
466 if (cvm_oct_device[i]) {
467 dev_for_napi = cvm_oct_device[i];
473 panic("No net_devices were allocated.");
475 for (i = 0; i < ARRAY_SIZE(oct_rx_group); i++) {
478 if (!(pow_receive_groups & BIT(i)))
481 netif_napi_add(dev_for_napi, &oct_rx_group[i].napi,
482 cvm_oct_napi_poll, rx_napi_weight);
483 napi_enable(&oct_rx_group[i].napi);
485 oct_rx_group[i].irq = OCTEON_IRQ_WORKQ0 + i;
486 oct_rx_group[i].group = i;
488 /* Register an IRQ handler to receive POW interrupts */
489 ret = request_irq(oct_rx_group[i].irq, cvm_oct_do_interrupt, 0,
490 "Ethernet", &oct_rx_group[i].napi);
492 panic("Could not acquire Ethernet IRQ %d\n",
493 oct_rx_group[i].irq);
495 disable_irq_nosync(oct_rx_group[i].irq);
497 /* Enable POW interrupt when our port has at least one packet */
498 if (OCTEON_IS_MODEL(OCTEON_CN68XX)) {
499 union cvmx_sso_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_SSO_WQ_INT_THRX(i), int_thr.u64);
509 cvmx_write_csr(CVMX_SSO_WQ_INT_PC, int_pc.u64);
511 union cvmx_pow_wq_int_thrx int_thr;
512 union cvmx_pow_wq_int_pc int_pc;
516 int_thr.s.tc_thr = 1;
517 cvmx_write_csr(CVMX_POW_WQ_INT_THRX(i), int_thr.u64);
521 cvmx_write_csr(CVMX_POW_WQ_INT_PC, int_pc.u64);
524 /* Schedule NAPI now. This will indirectly enable the
527 napi_schedule(&oct_rx_group[i].napi);
529 atomic_inc(&oct_rx_ready);
532 void cvm_oct_rx_shutdown(void)
536 for (i = 0; i < ARRAY_SIZE(oct_rx_group); i++) {
537 if (!(pow_receive_groups & BIT(i)))
540 /* Disable POW interrupt */
541 if (OCTEON_IS_MODEL(OCTEON_CN68XX))
542 cvmx_write_csr(CVMX_SSO_WQ_INT_THRX(i), 0);
544 cvmx_write_csr(CVMX_POW_WQ_INT_THRX(i), 0);
546 /* Free the interrupt handler */
547 free_irq(oct_rx_group[i].irq, cvm_oct_device);
549 netif_napi_del(&oct_rx_group[i].napi);