1/* SPDX-License-Identifier: BSD-3-Clause */
2/*  Copyright (c) 2024, Intel Corporation
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10 *
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14 *
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30 */
31
32/**
33 * @file ice_rss.h
34 * @brief default RSS values if kernel RSS is not enabled
35 *
36 * This header includes default definitions for RSS functionality if the
37 * kernel RSS interface is not enabled. This allows main driver code to avoid
38 * having to check the RSS ifdef throughout, but instead just use the RSS
39 * definitions, as they will fall back to these defaults when the kernel
40 * interface is disabled.
41 */
42#ifndef _ICE_RSS_H_
43#define _ICE_RSS_H_
44
45#ifdef RSS
46// We have the kernel RSS interface available
47#include <net/rss_config.h>
48
49/* Make sure our key size buffer has enough space to store the kernel RSS key */
50CTASSERT(ICE_AQC_GET_SET_RSS_KEY_DATA_RSS_KEY_SIZE >= RSS_KEYSIZE);
51#else
52/* The kernel RSS interface is not enabled. Use suitable defaults for the RSS
53 * configuration functions.
54 *
55 * The RSS hash key will be a pre-generated random key.
56 * The number of buckets will just match the number of CPUs.
57 * The lookup table will be assigned using round-robin with no indirection.
58 * The RSS hash configuration will be set to suitable defaults.
59 */
60
61#define	RSS_HASHTYPE_RSS_IPV4		(1 << 1)	/* IPv4 2-tuple */
62#define	RSS_HASHTYPE_RSS_TCP_IPV4	(1 << 2)	/* TCPv4 4-tuple */
63#define	RSS_HASHTYPE_RSS_IPV6		(1 << 3)	/* IPv6 2-tuple */
64#define	RSS_HASHTYPE_RSS_TCP_IPV6	(1 << 4)	/* TCPv6 4-tuple */
65#define	RSS_HASHTYPE_RSS_IPV6_EX	(1 << 5)	/* IPv6 2-tuple + ext hdrs */
66#define	RSS_HASHTYPE_RSS_TCP_IPV6_EX	(1 << 6)	/* TCPv6 4-tiple + ext hdrs */
67#define	RSS_HASHTYPE_RSS_UDP_IPV4	(1 << 7)	/* IPv4 UDP 4-tuple */
68#define	RSS_HASHTYPE_RSS_UDP_IPV6	(1 << 9)	/* IPv6 UDP 4-tuple */
69#define	RSS_HASHTYPE_RSS_UDP_IPV6_EX	(1 << 10)	/* IPv6 UDP 4-tuple + ext hdrs */
70
71#define ICE_DEFAULT_RSS_HASH_CONFIG \
72	((u_int)(RSS_HASHTYPE_RSS_IPV4 | \
73		 RSS_HASHTYPE_RSS_TCP_IPV4 | \
74		 RSS_HASHTYPE_RSS_UDP_IPV4 | \
75		 RSS_HASHTYPE_RSS_IPV6 | \
76		 RSS_HASHTYPE_RSS_TCP_IPV6 | \
77		 RSS_HASHTYPE_RSS_UDP_IPV6))
78
79#define rss_getkey(key) ice_get_default_rss_key(key)
80#define rss_getnumbuckets() (mp_ncpus)
81#define rss_get_indirection_to_bucket(index) (index)
82#define rss_gethashconfig() (ICE_DEFAULT_RSS_HASH_CONFIG)
83
84/**
85 * rss_hash2bucket - Determine the bucket for a given hash value
86 * @hash_val: the hash value to use
87 * @hash_type: the type of the hash
88 * @bucket_id: on success, updated with the bucket
89 *
90 * This function simply verifies that the hash type is known. If it is, then
91 * we forward the hash value directly as the bucket id. If the hash type is
92 * unknown, we return -1.
93 *
94 * This is the simplest mechanism for converting a hash value into a bucket,
95 * and does not support any form of indirection table.
96 */
97static inline int
98rss_hash2bucket(uint32_t hash_val, uint32_t hash_type, uint32_t *bucket_id)
99{
100	switch (hash_type) {
101	case M_HASHTYPE_RSS_IPV4:
102	case M_HASHTYPE_RSS_TCP_IPV4:
103	case M_HASHTYPE_RSS_UDP_IPV4:
104	case M_HASHTYPE_RSS_IPV6:
105	case M_HASHTYPE_RSS_TCP_IPV6:
106	case M_HASHTYPE_RSS_UDP_IPV6:
107		*bucket_id = hash_val;
108		return (0);
109	default:
110		return (-1);
111	}
112}
113
114#endif /* !RSS */
115
116#endif /* _ICE_COMMON_COMPAT_H_ */
117