558 lines
18 KiB
C
558 lines
18 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
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/* Copyright(c) 2013 - 2018 Intel Corporation. */
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#ifndef _I40E_TXRX_H_
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#define _I40E_TXRX_H_
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#include <net/xdp.h>
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/* Interrupt Throttling and Rate Limiting Goodies */
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#define I40E_DEFAULT_IRQ_WORK 256
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/* The datasheet for the X710 and XL710 indicate that the maximum value for
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* the ITR is 8160usec which is then called out as 0xFF0 with a 2usec
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* resolution. 8160 is 0x1FE0 when written out in hex. So instead of storing
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* the register value which is divided by 2 lets use the actual values and
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* avoid an excessive amount of translation.
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*/
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#define I40E_ITR_DYNAMIC 0x8000 /* use top bit as a flag */
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#define I40E_ITR_MASK 0x1FFE /* mask for ITR register value */
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#define I40E_MIN_ITR 2 /* reg uses 2 usec resolution */
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#define I40E_ITR_20K 50
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#define I40E_ITR_8K 122
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#define I40E_MAX_ITR 8160 /* maximum value as per datasheet */
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#define ITR_TO_REG(setting) ((setting) & ~I40E_ITR_DYNAMIC)
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#define ITR_REG_ALIGN(setting) __ALIGN_MASK(setting, ~I40E_ITR_MASK)
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#define ITR_IS_DYNAMIC(setting) (!!((setting) & I40E_ITR_DYNAMIC))
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#define I40E_ITR_RX_DEF (I40E_ITR_20K | I40E_ITR_DYNAMIC)
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#define I40E_ITR_TX_DEF (I40E_ITR_20K | I40E_ITR_DYNAMIC)
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/* 0x40 is the enable bit for interrupt rate limiting, and must be set if
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* the value of the rate limit is non-zero
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*/
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#define INTRL_ENA BIT(6)
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#define I40E_MAX_INTRL 0x3B /* reg uses 4 usec resolution */
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#define INTRL_REG_TO_USEC(intrl) ((intrl & ~INTRL_ENA) << 2)
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/**
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* i40e_intrl_usec_to_reg - convert interrupt rate limit to register
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* @intrl: interrupt rate limit to convert
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*
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* This function converts a decimal interrupt rate limit to the appropriate
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* register format expected by the firmware when setting interrupt rate limit.
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*/
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static inline u16 i40e_intrl_usec_to_reg(int intrl)
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{
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if (intrl >> 2)
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return ((intrl >> 2) | INTRL_ENA);
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else
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return 0;
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}
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#define I40E_QUEUE_END_OF_LIST 0x7FF
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/* this enum matches hardware bits and is meant to be used by DYN_CTLN
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* registers and QINT registers or more generally anywhere in the manual
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* mentioning ITR_INDX, ITR_NONE cannot be used as an index 'n' into any
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* register but instead is a special value meaning "don't update" ITR0/1/2.
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*/
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enum i40e_dyn_idx_t {
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I40E_IDX_ITR0 = 0,
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I40E_IDX_ITR1 = 1,
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I40E_IDX_ITR2 = 2,
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I40E_ITR_NONE = 3 /* ITR_NONE must not be used as an index */
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};
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/* these are indexes into ITRN registers */
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#define I40E_RX_ITR I40E_IDX_ITR0
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#define I40E_TX_ITR I40E_IDX_ITR1
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/* Supported RSS offloads */
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#define I40E_DEFAULT_RSS_HENA ( \
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BIT_ULL(I40E_FILTER_PCTYPE_NONF_IPV4_UDP) | \
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BIT_ULL(I40E_FILTER_PCTYPE_NONF_IPV4_SCTP) | \
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BIT_ULL(I40E_FILTER_PCTYPE_NONF_IPV4_TCP) | \
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BIT_ULL(I40E_FILTER_PCTYPE_NONF_IPV4_OTHER) | \
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BIT_ULL(I40E_FILTER_PCTYPE_FRAG_IPV4) | \
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BIT_ULL(I40E_FILTER_PCTYPE_NONF_IPV6_UDP) | \
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BIT_ULL(I40E_FILTER_PCTYPE_NONF_IPV6_TCP) | \
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BIT_ULL(I40E_FILTER_PCTYPE_NONF_IPV6_SCTP) | \
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BIT_ULL(I40E_FILTER_PCTYPE_NONF_IPV6_OTHER) | \
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BIT_ULL(I40E_FILTER_PCTYPE_FRAG_IPV6) | \
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BIT_ULL(I40E_FILTER_PCTYPE_L2_PAYLOAD))
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#define I40E_DEFAULT_RSS_HENA_EXPANDED (I40E_DEFAULT_RSS_HENA | \
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BIT_ULL(I40E_FILTER_PCTYPE_NONF_IPV4_TCP_SYN_NO_ACK) | \
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BIT_ULL(I40E_FILTER_PCTYPE_NONF_UNICAST_IPV4_UDP) | \
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BIT_ULL(I40E_FILTER_PCTYPE_NONF_MULTICAST_IPV4_UDP) | \
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BIT_ULL(I40E_FILTER_PCTYPE_NONF_IPV6_TCP_SYN_NO_ACK) | \
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BIT_ULL(I40E_FILTER_PCTYPE_NONF_UNICAST_IPV6_UDP) | \
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BIT_ULL(I40E_FILTER_PCTYPE_NONF_MULTICAST_IPV6_UDP))
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#define i40e_pf_get_default_rss_hena(pf) \
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(((pf)->hw_features & I40E_HW_MULTIPLE_TCP_UDP_RSS_PCTYPE) ? \
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I40E_DEFAULT_RSS_HENA_EXPANDED : I40E_DEFAULT_RSS_HENA)
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/* Supported Rx Buffer Sizes (a multiple of 128) */
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#define I40E_RXBUFFER_256 256
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#define I40E_RXBUFFER_1536 1536 /* 128B aligned standard Ethernet frame */
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#define I40E_RXBUFFER_2048 2048
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#define I40E_RXBUFFER_3072 3072 /* Used for large frames w/ padding */
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#define I40E_MAX_RXBUFFER 9728 /* largest size for single descriptor */
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/* NOTE: netdev_alloc_skb reserves up to 64 bytes, NET_IP_ALIGN means we
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* reserve 2 more, and skb_shared_info adds an additional 384 bytes more,
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* this adds up to 512 bytes of extra data meaning the smallest allocation
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* we could have is 1K.
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* i.e. RXBUFFER_256 --> 960 byte skb (size-1024 slab)
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* i.e. RXBUFFER_512 --> 1216 byte skb (size-2048 slab)
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*/
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#define I40E_RX_HDR_SIZE I40E_RXBUFFER_256
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#define I40E_PACKET_HDR_PAD (ETH_HLEN + ETH_FCS_LEN + (VLAN_HLEN * 2))
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#define i40e_rx_desc i40e_16byte_rx_desc
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#define I40E_RX_DMA_ATTR \
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(DMA_ATTR_SKIP_CPU_SYNC | DMA_ATTR_WEAK_ORDERING)
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/* Attempt to maximize the headroom available for incoming frames. We
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* use a 2K buffer for receives and need 1536/1534 to store the data for
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* the frame. This leaves us with 512 bytes of room. From that we need
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* to deduct the space needed for the shared info and the padding needed
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* to IP align the frame.
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*
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* Note: For cache line sizes 256 or larger this value is going to end
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* up negative. In these cases we should fall back to the legacy
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* receive path.
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*/
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#if (PAGE_SIZE < 8192)
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#define I40E_2K_TOO_SMALL_WITH_PADDING \
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((NET_SKB_PAD + I40E_RXBUFFER_1536) > SKB_WITH_OVERHEAD(I40E_RXBUFFER_2048))
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static inline int i40e_compute_pad(int rx_buf_len)
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{
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int page_size, pad_size;
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page_size = ALIGN(rx_buf_len, PAGE_SIZE / 2);
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pad_size = SKB_WITH_OVERHEAD(page_size) - rx_buf_len;
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return pad_size;
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}
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static inline int i40e_skb_pad(void)
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{
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int rx_buf_len;
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/* If a 2K buffer cannot handle a standard Ethernet frame then
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* optimize padding for a 3K buffer instead of a 1.5K buffer.
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*
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* For a 3K buffer we need to add enough padding to allow for
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* tailroom due to NET_IP_ALIGN possibly shifting us out of
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* cache-line alignment.
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*/
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if (I40E_2K_TOO_SMALL_WITH_PADDING)
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rx_buf_len = I40E_RXBUFFER_3072 + SKB_DATA_ALIGN(NET_IP_ALIGN);
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else
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rx_buf_len = I40E_RXBUFFER_1536;
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/* if needed make room for NET_IP_ALIGN */
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rx_buf_len -= NET_IP_ALIGN;
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return i40e_compute_pad(rx_buf_len);
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}
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#define I40E_SKB_PAD i40e_skb_pad()
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#else
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#define I40E_2K_TOO_SMALL_WITH_PADDING false
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#define I40E_SKB_PAD (NET_SKB_PAD + NET_IP_ALIGN)
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#endif
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/**
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* i40e_test_staterr - tests bits in Rx descriptor status and error fields
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* @rx_desc: pointer to receive descriptor (in le64 format)
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* @stat_err_bits: value to mask
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*
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* This function does some fast chicanery in order to return the
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* value of the mask which is really only used for boolean tests.
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* The status_error_len doesn't need to be shifted because it begins
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* at offset zero.
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*/
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static inline bool i40e_test_staterr(union i40e_rx_desc *rx_desc,
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const u64 stat_err_bits)
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{
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return !!(rx_desc->wb.qword1.status_error_len &
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cpu_to_le64(stat_err_bits));
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}
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/* How many Rx Buffers do we bundle into one write to the hardware ? */
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#define I40E_RX_BUFFER_WRITE 32 /* Must be power of 2 */
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#define I40E_RX_NEXT_DESC(r, i, n) \
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do { \
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(i)++; \
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if ((i) == (r)->count) \
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i = 0; \
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(n) = I40E_RX_DESC((r), (i)); \
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} while (0)
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#define I40E_MAX_BUFFER_TXD 8
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#define I40E_MIN_TX_LEN 17
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/* The size limit for a transmit buffer in a descriptor is (16K - 1).
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* In order to align with the read requests we will align the value to
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* the nearest 4K which represents our maximum read request size.
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*/
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#define I40E_MAX_READ_REQ_SIZE 4096
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#define I40E_MAX_DATA_PER_TXD (16 * 1024 - 1)
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#define I40E_MAX_DATA_PER_TXD_ALIGNED \
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(I40E_MAX_DATA_PER_TXD & ~(I40E_MAX_READ_REQ_SIZE - 1))
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/**
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* i40e_txd_use_count - estimate the number of descriptors needed for Tx
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* @size: transmit request size in bytes
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*
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* Due to hardware alignment restrictions (4K alignment), we need to
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* assume that we can have no more than 12K of data per descriptor, even
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* though each descriptor can take up to 16K - 1 bytes of aligned memory.
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* Thus, we need to divide by 12K. But division is slow! Instead,
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* we decompose the operation into shifts and one relatively cheap
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* multiply operation.
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*
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* To divide by 12K, we first divide by 4K, then divide by 3:
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* To divide by 4K, shift right by 12 bits
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* To divide by 3, multiply by 85, then divide by 256
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* (Divide by 256 is done by shifting right by 8 bits)
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* Finally, we add one to round up. Because 256 isn't an exact multiple of
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* 3, we'll underestimate near each multiple of 12K. This is actually more
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* accurate as we have 4K - 1 of wiggle room that we can fit into the last
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* segment. For our purposes this is accurate out to 1M which is orders of
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* magnitude greater than our largest possible GSO size.
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*
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* This would then be implemented as:
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* return (((size >> 12) * 85) >> 8) + 1;
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*
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* Since multiplication and division are commutative, we can reorder
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* operations into:
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* return ((size * 85) >> 20) + 1;
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*/
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static inline unsigned int i40e_txd_use_count(unsigned int size)
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{
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return ((size * 85) >> 20) + 1;
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}
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/* Tx Descriptors needed, worst case */
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#define DESC_NEEDED (MAX_SKB_FRAGS + 6)
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#define I40E_TX_FLAGS_HW_VLAN BIT(1)
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#define I40E_TX_FLAGS_SW_VLAN BIT(2)
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#define I40E_TX_FLAGS_TSO BIT(3)
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#define I40E_TX_FLAGS_IPV4 BIT(4)
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#define I40E_TX_FLAGS_IPV6 BIT(5)
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#define I40E_TX_FLAGS_TSYN BIT(8)
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#define I40E_TX_FLAGS_FD_SB BIT(9)
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#define I40E_TX_FLAGS_UDP_TUNNEL BIT(10)
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#define I40E_TX_FLAGS_VLAN_MASK 0xffff0000
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#define I40E_TX_FLAGS_VLAN_PRIO_MASK 0xe0000000
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#define I40E_TX_FLAGS_VLAN_PRIO_SHIFT 29
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#define I40E_TX_FLAGS_VLAN_SHIFT 16
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struct i40e_tx_buffer {
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struct i40e_tx_desc *next_to_watch;
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union {
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struct xdp_frame *xdpf;
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struct sk_buff *skb;
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void *raw_buf;
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};
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unsigned int bytecount;
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unsigned short gso_segs;
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DEFINE_DMA_UNMAP_ADDR(dma);
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DEFINE_DMA_UNMAP_LEN(len);
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u32 tx_flags;
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};
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struct i40e_rx_buffer {
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dma_addr_t dma;
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struct page *page;
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__u32 page_offset;
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__u16 pagecnt_bias;
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};
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struct i40e_queue_stats {
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u64 packets;
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u64 bytes;
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};
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struct i40e_tx_queue_stats {
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u64 restart_queue;
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u64 tx_busy;
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u64 tx_done_old;
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u64 tx_linearize;
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u64 tx_force_wb;
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u64 tx_stopped;
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int prev_pkt_ctr;
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};
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struct i40e_rx_queue_stats {
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u64 non_eop_descs;
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u64 alloc_page_failed;
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u64 alloc_buff_failed;
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u64 page_reuse_count;
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u64 page_alloc_count;
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u64 page_waive_count;
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u64 page_busy_count;
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};
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enum i40e_ring_state_t {
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__I40E_TX_FDIR_INIT_DONE,
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__I40E_TX_XPS_INIT_DONE,
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__I40E_RING_STATE_NBITS /* must be last */
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};
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/* some useful defines for virtchannel interface, which
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* is the only remaining user of header split
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*/
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#define I40E_RX_DTYPE_HEADER_SPLIT 1
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#define I40E_RX_SPLIT_L2 0x1
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#define I40E_RX_SPLIT_IP 0x2
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#define I40E_RX_SPLIT_TCP_UDP 0x4
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#define I40E_RX_SPLIT_SCTP 0x8
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/* struct that defines a descriptor ring, associated with a VSI */
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struct i40e_ring {
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struct i40e_ring *next; /* pointer to next ring in q_vector */
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void *desc; /* Descriptor ring memory */
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struct device *dev; /* Used for DMA mapping */
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struct net_device *netdev; /* netdev ring maps to */
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struct bpf_prog *xdp_prog;
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union {
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struct i40e_tx_buffer *tx_bi;
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struct i40e_rx_buffer *rx_bi;
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struct xdp_buff **rx_bi_zc;
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};
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DECLARE_BITMAP(state, __I40E_RING_STATE_NBITS);
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u16 queue_index; /* Queue number of ring */
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u8 dcb_tc; /* Traffic class of ring */
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u8 __iomem *tail;
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/* high bit set means dynamic, use accessor routines to read/write.
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* hardware only supports 2us resolution for the ITR registers.
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* these values always store the USER setting, and must be converted
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* before programming to a register.
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*/
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u16 itr_setting;
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u16 count; /* Number of descriptors */
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u16 reg_idx; /* HW register index of the ring */
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u16 rx_buf_len;
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/* used in interrupt processing */
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u16 next_to_use;
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u16 next_to_clean;
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u16 xdp_tx_active;
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u8 atr_sample_rate;
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u8 atr_count;
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bool ring_active; /* is ring online or not */
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bool arm_wb; /* do something to arm write back */
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u8 packet_stride;
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u16 flags;
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#define I40E_TXR_FLAGS_WB_ON_ITR BIT(0)
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#define I40E_RXR_FLAGS_BUILD_SKB_ENABLED BIT(1)
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#define I40E_TXR_FLAGS_XDP BIT(2)
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/* stats structs */
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struct i40e_queue_stats stats;
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struct u64_stats_sync syncp;
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union {
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struct i40e_tx_queue_stats tx_stats;
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struct i40e_rx_queue_stats rx_stats;
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};
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unsigned int size; /* length of descriptor ring in bytes */
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dma_addr_t dma; /* physical address of ring */
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struct i40e_vsi *vsi; /* Backreference to associated VSI */
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struct i40e_q_vector *q_vector; /* Backreference to associated vector */
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struct rcu_head rcu; /* to avoid race on free */
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u16 next_to_alloc;
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struct sk_buff *skb; /* When i40e_clean_rx_ring_irq() must
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* return before it sees the EOP for
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* the current packet, we save that skb
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* here and resume receiving this
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* packet the next time
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* i40e_clean_rx_ring_irq() is called
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* for this ring.
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*/
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struct i40e_channel *ch;
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u16 rx_offset;
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struct xdp_rxq_info xdp_rxq;
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struct xsk_buff_pool *xsk_pool;
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} ____cacheline_internodealigned_in_smp;
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static inline bool ring_uses_build_skb(struct i40e_ring *ring)
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{
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return !!(ring->flags & I40E_RXR_FLAGS_BUILD_SKB_ENABLED);
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}
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static inline void set_ring_build_skb_enabled(struct i40e_ring *ring)
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{
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ring->flags |= I40E_RXR_FLAGS_BUILD_SKB_ENABLED;
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}
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static inline void clear_ring_build_skb_enabled(struct i40e_ring *ring)
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{
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ring->flags &= ~I40E_RXR_FLAGS_BUILD_SKB_ENABLED;
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}
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static inline bool ring_is_xdp(struct i40e_ring *ring)
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{
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return !!(ring->flags & I40E_TXR_FLAGS_XDP);
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}
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static inline void set_ring_xdp(struct i40e_ring *ring)
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{
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ring->flags |= I40E_TXR_FLAGS_XDP;
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}
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#define I40E_ITR_ADAPTIVE_MIN_INC 0x0002
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#define I40E_ITR_ADAPTIVE_MIN_USECS 0x0002
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#define I40E_ITR_ADAPTIVE_MAX_USECS 0x007e
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#define I40E_ITR_ADAPTIVE_LATENCY 0x8000
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#define I40E_ITR_ADAPTIVE_BULK 0x0000
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struct i40e_ring_container {
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struct i40e_ring *ring; /* pointer to linked list of ring(s) */
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unsigned long next_update; /* jiffies value of next update */
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unsigned int total_bytes; /* total bytes processed this int */
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unsigned int total_packets; /* total packets processed this int */
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u16 count;
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u16 target_itr; /* target ITR setting for ring(s) */
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u16 current_itr; /* current ITR setting for ring(s) */
|
|
};
|
|
|
|
/* iterator for handling rings in ring container */
|
|
#define i40e_for_each_ring(pos, head) \
|
|
for (pos = (head).ring; pos != NULL; pos = pos->next)
|
|
|
|
static inline unsigned int i40e_rx_pg_order(struct i40e_ring *ring)
|
|
{
|
|
#if (PAGE_SIZE < 8192)
|
|
if (ring->rx_buf_len > (PAGE_SIZE / 2))
|
|
return 1;
|
|
#endif
|
|
return 0;
|
|
}
|
|
|
|
#define i40e_rx_pg_size(_ring) (PAGE_SIZE << i40e_rx_pg_order(_ring))
|
|
|
|
bool i40e_alloc_rx_buffers(struct i40e_ring *rxr, u16 cleaned_count);
|
|
netdev_tx_t i40e_lan_xmit_frame(struct sk_buff *skb, struct net_device *netdev);
|
|
u16 i40e_lan_select_queue(struct net_device *netdev, struct sk_buff *skb,
|
|
struct net_device *sb_dev);
|
|
void i40e_clean_tx_ring(struct i40e_ring *tx_ring);
|
|
void i40e_clean_rx_ring(struct i40e_ring *rx_ring);
|
|
int i40e_setup_tx_descriptors(struct i40e_ring *tx_ring);
|
|
int i40e_setup_rx_descriptors(struct i40e_ring *rx_ring);
|
|
void i40e_free_tx_resources(struct i40e_ring *tx_ring);
|
|
void i40e_free_rx_resources(struct i40e_ring *rx_ring);
|
|
int i40e_napi_poll(struct napi_struct *napi, int budget);
|
|
void i40e_force_wb(struct i40e_vsi *vsi, struct i40e_q_vector *q_vector);
|
|
u32 i40e_get_tx_pending(struct i40e_ring *ring, bool in_sw);
|
|
void i40e_detect_recover_hung(struct i40e_vsi *vsi);
|
|
int __i40e_maybe_stop_tx(struct i40e_ring *tx_ring, int size);
|
|
bool __i40e_chk_linearize(struct sk_buff *skb);
|
|
int i40e_xdp_xmit(struct net_device *dev, int n, struct xdp_frame **frames,
|
|
u32 flags);
|
|
|
|
/**
|
|
* i40e_get_head - Retrieve head from head writeback
|
|
* @tx_ring: tx ring to fetch head of
|
|
*
|
|
* Returns value of Tx ring head based on value stored
|
|
* in head write-back location
|
|
**/
|
|
static inline u32 i40e_get_head(struct i40e_ring *tx_ring)
|
|
{
|
|
void *head = (struct i40e_tx_desc *)tx_ring->desc + tx_ring->count;
|
|
|
|
return le32_to_cpu(*(volatile __le32 *)head);
|
|
}
|
|
|
|
/**
|
|
* i40e_xmit_descriptor_count - calculate number of Tx descriptors needed
|
|
* @skb: send buffer
|
|
*
|
|
* Returns number of data descriptors needed for this skb. Returns 0 to indicate
|
|
* there is not enough descriptors available in this ring since we need at least
|
|
* one descriptor.
|
|
**/
|
|
static inline int i40e_xmit_descriptor_count(struct sk_buff *skb)
|
|
{
|
|
const skb_frag_t *frag = &skb_shinfo(skb)->frags[0];
|
|
unsigned int nr_frags = skb_shinfo(skb)->nr_frags;
|
|
int count = 0, size = skb_headlen(skb);
|
|
|
|
for (;;) {
|
|
count += i40e_txd_use_count(size);
|
|
|
|
if (!nr_frags--)
|
|
break;
|
|
|
|
size = skb_frag_size(frag++);
|
|
}
|
|
|
|
return count;
|
|
}
|
|
|
|
/**
|
|
* i40e_maybe_stop_tx - 1st level check for Tx stop conditions
|
|
* @tx_ring: the ring to be checked
|
|
* @size: the size buffer we want to assure is available
|
|
*
|
|
* Returns 0 if stop is not needed
|
|
**/
|
|
static inline int i40e_maybe_stop_tx(struct i40e_ring *tx_ring, int size)
|
|
{
|
|
if (likely(I40E_DESC_UNUSED(tx_ring) >= size))
|
|
return 0;
|
|
return __i40e_maybe_stop_tx(tx_ring, size);
|
|
}
|
|
|
|
/**
|
|
* i40e_chk_linearize - Check if there are more than 8 fragments per packet
|
|
* @skb: send buffer
|
|
* @count: number of buffers used
|
|
*
|
|
* Note: Our HW can't scatter-gather more than 8 fragments to build
|
|
* a packet on the wire and so we need to figure out the cases where we
|
|
* need to linearize the skb.
|
|
**/
|
|
static inline bool i40e_chk_linearize(struct sk_buff *skb, int count)
|
|
{
|
|
/* Both TSO and single send will work if count is less than 8 */
|
|
if (likely(count < I40E_MAX_BUFFER_TXD))
|
|
return false;
|
|
|
|
if (skb_is_gso(skb))
|
|
return __i40e_chk_linearize(skb);
|
|
|
|
/* we can support up to 8 data buffers for a single send */
|
|
return count != I40E_MAX_BUFFER_TXD;
|
|
}
|
|
|
|
/**
|
|
* txring_txq - Find the netdev Tx ring based on the i40e Tx ring
|
|
* @ring: Tx ring to find the netdev equivalent of
|
|
**/
|
|
static inline struct netdev_queue *txring_txq(const struct i40e_ring *ring)
|
|
{
|
|
return netdev_get_tx_queue(ring->netdev, ring->queue_index);
|
|
}
|
|
#endif /* _I40E_TXRX_H_ */
|