diff options
Diffstat (limited to 'drivers/staging/octeon/ethernet-rx.c')
| -rw-r--r-- | drivers/staging/octeon/ethernet-rx.c | 489 |
1 files changed, 489 insertions, 0 deletions
diff --git a/drivers/staging/octeon/ethernet-rx.c b/drivers/staging/octeon/ethernet-rx.c new file mode 100644 index 000000000..22667dbb1 --- /dev/null +++ b/drivers/staging/octeon/ethernet-rx.c @@ -0,0 +1,489 @@ +/********************************************************************** + * Author: Cavium Networks + * + * Contact: support@caviumnetworks.com + * This file is part of the OCTEON SDK + * + * Copyright (c) 2003-2010 Cavium Networks + * + * This file is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License, Version 2, as + * published by the Free Software Foundation. + * + * This file is distributed in the hope that it will be useful, but + * AS-IS and WITHOUT ANY WARRANTY; without even the implied warranty + * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, TITLE, or + * NONINFRINGEMENT. See the GNU General Public License for more + * details. + * + * You should have received a copy of the GNU General Public License + * along with this file; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * or visit http://www.gnu.org/licenses/. + * + * This file may also be available under a different license from Cavium. + * Contact Cavium Networks for more information +**********************************************************************/ +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/cache.h> +#include <linux/cpumask.h> +#include <linux/netdevice.h> +#include <linux/etherdevice.h> +#include <linux/ip.h> +#include <linux/string.h> +#include <linux/prefetch.h> +#include <linux/ratelimit.h> +#include <linux/smp.h> +#include <linux/interrupt.h> +#include <net/dst.h> +#ifdef CONFIG_XFRM +#include <linux/xfrm.h> +#include <net/xfrm.h> +#endif /* CONFIG_XFRM */ + +#include <linux/atomic.h> + +#include <asm/octeon/octeon.h> + +#include "ethernet-defines.h" +#include "ethernet-mem.h" +#include "ethernet-rx.h" +#include "octeon-ethernet.h" +#include "ethernet-util.h" + +#include <asm/octeon/cvmx-helper.h> +#include <asm/octeon/cvmx-wqe.h> +#include <asm/octeon/cvmx-fau.h> +#include <asm/octeon/cvmx-pow.h> +#include <asm/octeon/cvmx-pip.h> +#include <asm/octeon/cvmx-scratch.h> + +#include <asm/octeon/cvmx-gmxx-defs.h> + +static struct napi_struct cvm_oct_napi; + +/** + * cvm_oct_do_interrupt - interrupt handler. + * + * The interrupt occurs whenever the POW has packets in our group. + * + */ +static irqreturn_t cvm_oct_do_interrupt(int cpl, void *dev_id) +{ + /* Disable the IRQ and start napi_poll. */ + disable_irq_nosync(OCTEON_IRQ_WORKQ0 + pow_receive_group); + napi_schedule(&cvm_oct_napi); + + return IRQ_HANDLED; +} + +/** + * cvm_oct_check_rcv_error - process receive errors + * @work: Work queue entry pointing to the packet. + * + * Returns Non-zero if the packet can be dropped, zero otherwise. + */ +static inline int cvm_oct_check_rcv_error(cvmx_wqe_t *work) +{ + if ((work->word2.snoip.err_code == 10) && (work->len <= 64)) { + /* + * Ignore length errors on min size packets. Some + * equipment incorrectly pads packets to 64+4FCS + * instead of 60+4FCS. Note these packets still get + * counted as frame errors. + */ + } else + if (USE_10MBPS_PREAMBLE_WORKAROUND + && ((work->word2.snoip.err_code == 5) + || (work->word2.snoip.err_code == 7))) { + + /* + * We received a packet with either an alignment error + * or a FCS error. This may be signalling that we are + * running 10Mbps with GMXX_RXX_FRM_CTL[PRE_CHK] + * off. If this is the case we need to parse the + * packet to determine if we can remove a non spec + * preamble and generate a correct packet. + */ + int interface = cvmx_helper_get_interface_num(work->ipprt); + int index = cvmx_helper_get_interface_index_num(work->ipprt); + union cvmx_gmxx_rxx_frm_ctl gmxx_rxx_frm_ctl; + + gmxx_rxx_frm_ctl.u64 = + cvmx_read_csr(CVMX_GMXX_RXX_FRM_CTL(index, interface)); + if (gmxx_rxx_frm_ctl.s.pre_chk == 0) { + + uint8_t *ptr = + cvmx_phys_to_ptr(work->packet_ptr.s.addr); + int i = 0; + + while (i < work->len - 1) { + if (*ptr != 0x55) + break; + ptr++; + i++; + } + + if (*ptr == 0xd5) { + /* + printk_ratelimited("Port %d received 0xd5 preamble\n", + work->ipprt); + */ + work->packet_ptr.s.addr += i + 1; + work->len -= i + 5; + } else if ((*ptr & 0xf) == 0xd) { + /* + printk_ratelimited("Port %d received 0x?d preamble\n", + work->ipprt); + */ + work->packet_ptr.s.addr += i; + work->len -= i + 4; + for (i = 0; i < work->len; i++) { + *ptr = + ((*ptr & 0xf0) >> 4) | + ((*(ptr + 1) & 0xf) << 4); + ptr++; + } + } else { + printk_ratelimited("Port %d unknown preamble, packet dropped\n", + work->ipprt); + /* + cvmx_helper_dump_packet(work); + */ + cvm_oct_free_work(work); + return 1; + } + } + } else { + printk_ratelimited("Port %d receive error code %d, packet dropped\n", + work->ipprt, work->word2.snoip.err_code); + cvm_oct_free_work(work); + return 1; + } + + return 0; +} + +/** + * cvm_oct_napi_poll - the NAPI poll function. + * @napi: The NAPI instance, or null if called from cvm_oct_poll_controller + * @budget: Maximum number of packets to receive. + * + * Returns the number of packets processed. + */ +static int cvm_oct_napi_poll(struct napi_struct *napi, int budget) +{ + const int coreid = cvmx_get_core_num(); + uint64_t old_group_mask; + uint64_t old_scratch; + int rx_count = 0; + int did_work_request = 0; + int packet_not_copied; + + /* Prefetch cvm_oct_device since we know we need it soon */ + prefetch(cvm_oct_device); + + if (USE_ASYNC_IOBDMA) { + /* Save scratch in case userspace is using it */ + CVMX_SYNCIOBDMA; + old_scratch = cvmx_scratch_read64(CVMX_SCR_SCRATCH); + } + + /* Only allow work for our group (and preserve priorities) */ + old_group_mask = cvmx_read_csr(CVMX_POW_PP_GRP_MSKX(coreid)); + cvmx_write_csr(CVMX_POW_PP_GRP_MSKX(coreid), + (old_group_mask & ~0xFFFFull) | 1 << pow_receive_group); + + if (USE_ASYNC_IOBDMA) { + cvmx_pow_work_request_async(CVMX_SCR_SCRATCH, CVMX_POW_NO_WAIT); + did_work_request = 1; + } + + while (rx_count < budget) { + struct sk_buff *skb = NULL; + struct sk_buff **pskb = NULL; + int skb_in_hw; + cvmx_wqe_t *work; + + if (USE_ASYNC_IOBDMA && did_work_request) + work = cvmx_pow_work_response_async(CVMX_SCR_SCRATCH); + else + work = cvmx_pow_work_request_sync(CVMX_POW_NO_WAIT); + + prefetch(work); + did_work_request = 0; + if (work == NULL) { + union cvmx_pow_wq_int wq_int; + + wq_int.u64 = 0; + wq_int.s.iq_dis = 1 << pow_receive_group; + wq_int.s.wq_int = 1 << pow_receive_group; + cvmx_write_csr(CVMX_POW_WQ_INT, wq_int.u64); + break; + } + pskb = (struct sk_buff **)(cvm_oct_get_buffer_ptr(work->packet_ptr) - + sizeof(void *)); + prefetch(pskb); + + if (USE_ASYNC_IOBDMA && rx_count < (budget - 1)) { + cvmx_pow_work_request_async_nocheck(CVMX_SCR_SCRATCH, + CVMX_POW_NO_WAIT); + did_work_request = 1; + } + rx_count++; + + skb_in_hw = USE_SKBUFFS_IN_HW && work->word2.s.bufs == 1; + if (likely(skb_in_hw)) { + skb = *pskb; + prefetch(&skb->head); + prefetch(&skb->len); + } + prefetch(cvm_oct_device[work->ipprt]); + + /* Immediately throw away all packets with receive errors */ + if (unlikely(work->word2.snoip.rcv_error)) { + if (cvm_oct_check_rcv_error(work)) + continue; + } + + /* + * We can only use the zero copy path if skbuffs are + * in the FPA pool and the packet fits in a single + * buffer. + */ + if (likely(skb_in_hw)) { + skb->data = skb->head + work->packet_ptr.s.addr - + cvmx_ptr_to_phys(skb->head); + prefetch(skb->data); + skb->len = work->len; + skb_set_tail_pointer(skb, skb->len); + packet_not_copied = 1; + } else { + /* + * We have to copy the packet. First allocate + * an skbuff for it. + */ + skb = dev_alloc_skb(work->len); + if (!skb) { + cvm_oct_free_work(work); + continue; + } + + /* + * Check if we've received a packet that was + * entirely stored in the work entry. + */ + if (unlikely(work->word2.s.bufs == 0)) { + uint8_t *ptr = work->packet_data; + + if (likely(!work->word2.s.not_IP)) { + /* + * The beginning of the packet + * moves for IP packets. + */ + if (work->word2.s.is_v6) + ptr += 2; + else + ptr += 6; + } + memcpy(skb_put(skb, work->len), ptr, work->len); + /* No packet buffers to free */ + } else { + int segments = work->word2.s.bufs; + union cvmx_buf_ptr segment_ptr = + work->packet_ptr; + int len = work->len; + + while (segments--) { + union cvmx_buf_ptr next_ptr = + *(union cvmx_buf_ptr *)cvmx_phys_to_ptr(segment_ptr.s.addr - 8); + + /* + * Octeon Errata PKI-100: The segment size is + * wrong. Until it is fixed, calculate the + * segment size based on the packet pool + * buffer size. When it is fixed, the + * following line should be replaced with this + * one: int segment_size = + * segment_ptr.s.size; + */ + int segment_size = + CVMX_FPA_PACKET_POOL_SIZE - + (segment_ptr.s.addr - + (((segment_ptr.s.addr >> 7) - + segment_ptr.s.back) << 7)); + /* + * Don't copy more than what + * is left in the packet. + */ + if (segment_size > len) + segment_size = len; + /* Copy the data into the packet */ + memcpy(skb_put(skb, segment_size), + cvmx_phys_to_ptr(segment_ptr.s.addr), + segment_size); + len -= segment_size; + segment_ptr = next_ptr; + } + } + packet_not_copied = 0; + } + + if (likely((work->ipprt < TOTAL_NUMBER_OF_PORTS) && + cvm_oct_device[work->ipprt])) { + struct net_device *dev = cvm_oct_device[work->ipprt]; + struct octeon_ethernet *priv = netdev_priv(dev); + + /* + * Only accept packets for devices that are + * currently up. + */ + if (likely(dev->flags & IFF_UP)) { + skb->protocol = eth_type_trans(skb, dev); + skb->dev = dev; + + if (unlikely(work->word2.s.not_IP || + work->word2.s.IP_exc || + work->word2.s.L4_error || + !work->word2.s.tcp_or_udp)) + skb->ip_summed = CHECKSUM_NONE; + else + skb->ip_summed = CHECKSUM_UNNECESSARY; + + /* Increment RX stats for virtual ports */ + if (work->ipprt >= CVMX_PIP_NUM_INPUT_PORTS) { +#ifdef CONFIG_64BIT + atomic64_add(1, + (atomic64_t *)&priv->stats.rx_packets); + atomic64_add(skb->len, + (atomic64_t *)&priv->stats.rx_bytes); +#else + atomic_add(1, + (atomic_t *)&priv->stats.rx_packets); + atomic_add(skb->len, + (atomic_t *)&priv->stats.rx_bytes); +#endif + } + netif_receive_skb(skb); + } else { + /* Drop any packet received for a device that isn't up */ + /* + printk_ratelimited("%s: Device not up, packet dropped\n", + dev->name); + */ +#ifdef CONFIG_64BIT + atomic64_add(1, + (atomic64_t *)&priv->stats.rx_dropped); +#else + atomic_add(1, + (atomic_t *)&priv->stats.rx_dropped); +#endif + dev_kfree_skb_irq(skb); + } + } else { + /* + * Drop any packet received for a device that + * doesn't exist. + */ + printk_ratelimited("Port %d not controlled by Linux, packet dropped\n", + work->ipprt); + dev_kfree_skb_irq(skb); + } + /* + * Check to see if the skbuff and work share the same + * packet buffer. + */ + if (USE_SKBUFFS_IN_HW && likely(packet_not_copied)) { + /* + * This buffer needs to be replaced, increment + * the number of buffers we need to free by + * one. + */ + cvmx_fau_atomic_add32(FAU_NUM_PACKET_BUFFERS_TO_FREE, + 1); + + cvmx_fpa_free(work, CVMX_FPA_WQE_POOL, + DONT_WRITEBACK(1)); + } else { + cvm_oct_free_work(work); + } + } + /* Restore the original POW group mask */ + cvmx_write_csr(CVMX_POW_PP_GRP_MSKX(coreid), old_group_mask); + if (USE_ASYNC_IOBDMA) { + /* Restore the scratch area */ + cvmx_scratch_write64(CVMX_SCR_SCRATCH, old_scratch); + } + cvm_oct_rx_refill_pool(0); + + if (rx_count < budget && napi != NULL) { + /* No more work */ + napi_complete(napi); + enable_irq(OCTEON_IRQ_WORKQ0 + pow_receive_group); + } + return rx_count; +} + +#ifdef CONFIG_NET_POLL_CONTROLLER +/** + * cvm_oct_poll_controller - poll for receive packets + * device. + * + * @dev: Device to poll. Unused + */ +void cvm_oct_poll_controller(struct net_device *dev) +{ + cvm_oct_napi_poll(NULL, 16); +} +#endif + +void cvm_oct_rx_initialize(void) +{ + int i; + struct net_device *dev_for_napi = NULL; + union cvmx_pow_wq_int_thrx int_thr; + union cvmx_pow_wq_int_pc int_pc; + + for (i = 0; i < TOTAL_NUMBER_OF_PORTS; i++) { + if (cvm_oct_device[i]) { + dev_for_napi = cvm_oct_device[i]; + break; + } + } + + if (NULL == dev_for_napi) + panic("No net_devices were allocated."); + + netif_napi_add(dev_for_napi, &cvm_oct_napi, cvm_oct_napi_poll, + rx_napi_weight); + napi_enable(&cvm_oct_napi); + + /* Register an IRQ handler to receive POW interrupts */ + i = request_irq(OCTEON_IRQ_WORKQ0 + pow_receive_group, + cvm_oct_do_interrupt, 0, "Ethernet", cvm_oct_device); + + if (i) + panic("Could not acquire Ethernet IRQ %d\n", + OCTEON_IRQ_WORKQ0 + pow_receive_group); + + disable_irq_nosync(OCTEON_IRQ_WORKQ0 + pow_receive_group); + + int_thr.u64 = 0; + int_thr.s.tc_en = 1; + int_thr.s.tc_thr = 1; + /* Enable POW interrupt when our port has at least one packet */ + cvmx_write_csr(CVMX_POW_WQ_INT_THRX(pow_receive_group), int_thr.u64); + + int_pc.u64 = 0; + int_pc.s.pc_thr = 5; + cvmx_write_csr(CVMX_POW_WQ_INT_PC, int_pc.u64); + + /* Schedule NAPI now. This will indirectly enable the interrupt. */ + napi_schedule(&cvm_oct_napi); +} + +void cvm_oct_rx_shutdown(void) +{ + netif_napi_del(&cvm_oct_napi); +} |