1// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2/* Copyright (c) 2020 Marvell International Ltd. All rights reserved */
3
4#include <linux/bitfield.h>
5#include <linux/bitops.h>
6#include <linux/errno.h>
7#include <linux/string.h>
8
9#include "prestera_dsa.h"
10
11#define PRESTERA_DSA_W0_CMD GENMASK(31, 30)
12#define PRESTERA_DSA_W0_IS_TAGGED BIT(29)
13#define PRESTERA_DSA_W0_DEV_NUM GENMASK(28, 24)
14#define PRESTERA_DSA_W0_PORT_NUM GENMASK(23, 19)
15#define PRESTERA_DSA_W0_VPT GENMASK(15, 13)
16#define PRESTERA_DSA_W0_EXT_BIT BIT(12)
17#define PRESTERA_DSA_W0_VID GENMASK(11, 0)
18
19#define PRESTERA_DSA_W1_EXT_BIT BIT(31)
20#define PRESTERA_DSA_W1_CFI_BIT BIT(30)
21#define PRESTERA_DSA_W1_PORT_NUM GENMASK(11, 10)
22#define PRESTERA_DSA_W1_MASK_CPU_CODE GENMASK(7, 0)
23
24#define PRESTERA_DSA_W2_EXT_BIT BIT(31)
25#define PRESTERA_DSA_W2_PORT_NUM BIT(20)
26
27#define PRESTERA_DSA_W3_VID GENMASK(30, 27)
28#define PRESTERA_DSA_W3_DST_EPORT GENMASK(23, 7)
29#define PRESTERA_DSA_W3_DEV_NUM GENMASK(6, 0)
30
31#define PRESTERA_DSA_VID GENMASK(15, 12)
32#define PRESTERA_DSA_DEV_NUM GENMASK(11, 5)
33
34int prestera_dsa_parse(struct prestera_dsa *dsa, const u8 *dsa_buf)
35{
36 __be32 *dsa_words = (__be32 *)dsa_buf;
37 enum prestera_dsa_cmd cmd;
38 u32 words[4];
39 u32 field;
40
41 words[0] = ntohl(dsa_words[0]);
42 words[1] = ntohl(dsa_words[1]);
43 words[2] = ntohl(dsa_words[2]);
44 words[3] = ntohl(dsa_words[3]);
45
46 /* set the common parameters */
47 cmd = (enum prestera_dsa_cmd)FIELD_GET(PRESTERA_DSA_W0_CMD, words[0]);
48
49 /* only to CPU is supported */
50 if (unlikely(cmd != PRESTERA_DSA_CMD_TO_CPU))
51 return -EINVAL;
52
53 if (FIELD_GET(PRESTERA_DSA_W0_EXT_BIT, words[0]) == 0)
54 return -EINVAL;
55 if (FIELD_GET(PRESTERA_DSA_W1_EXT_BIT, words[1]) == 0)
56 return -EINVAL;
57 if (FIELD_GET(PRESTERA_DSA_W2_EXT_BIT, words[2]) == 0)
58 return -EINVAL;
59
60 field = FIELD_GET(PRESTERA_DSA_W3_VID, words[3]);
61
62 dsa->vlan.is_tagged = FIELD_GET(PRESTERA_DSA_W0_IS_TAGGED, words[0]);
63 dsa->vlan.cfi_bit = FIELD_GET(PRESTERA_DSA_W1_CFI_BIT, words[1]);
64 dsa->vlan.vpt = FIELD_GET(PRESTERA_DSA_W0_VPT, words[0]);
65 dsa->vlan.vid = FIELD_GET(PRESTERA_DSA_W0_VID, words[0]);
66 dsa->vlan.vid &= ~PRESTERA_DSA_VID;
67 dsa->vlan.vid |= FIELD_PREP(PRESTERA_DSA_VID, field);
68
69 field = FIELD_GET(PRESTERA_DSA_W3_DEV_NUM, words[3]);
70
71 dsa->hw_dev_num = FIELD_GET(PRESTERA_DSA_W0_DEV_NUM, words[0]);
72 dsa->hw_dev_num |= FIELD_PREP(PRESTERA_DSA_DEV_NUM, field);
73
74 dsa->port_num = (FIELD_GET(PRESTERA_DSA_W0_PORT_NUM, words[0]) << 0) |
75 (FIELD_GET(PRESTERA_DSA_W1_PORT_NUM, words[1]) << 5) |
76 (FIELD_GET(PRESTERA_DSA_W2_PORT_NUM, words[2]) << 7);
77
78 dsa->cpu_code = FIELD_GET(PRESTERA_DSA_W1_MASK_CPU_CODE, words[1]);
79
80 return 0;
81}
82
83int prestera_dsa_build(const struct prestera_dsa *dsa, u8 *dsa_buf)
84{
85 __be32 *dsa_words = (__be32 *)dsa_buf;
86 u32 dev_num = dsa->hw_dev_num;
87 u32 words[4] = { 0 };
88
89 words[0] |= FIELD_PREP(PRESTERA_DSA_W0_CMD, PRESTERA_DSA_CMD_FROM_CPU);
90
91 words[0] |= FIELD_PREP(PRESTERA_DSA_W0_DEV_NUM, dev_num);
92 dev_num = FIELD_GET(PRESTERA_DSA_DEV_NUM, dev_num);
93 words[3] |= FIELD_PREP(PRESTERA_DSA_W3_DEV_NUM, dev_num);
94
95 words[3] |= FIELD_PREP(PRESTERA_DSA_W3_DST_EPORT, dsa->port_num);
96
97 words[0] |= FIELD_PREP(PRESTERA_DSA_W0_EXT_BIT, 1);
98 words[1] |= FIELD_PREP(PRESTERA_DSA_W1_EXT_BIT, 1);
99 words[2] |= FIELD_PREP(PRESTERA_DSA_W2_EXT_BIT, 1);
100
101 dsa_words[0] = htonl(words[0]);
102 dsa_words[1] = htonl(words[1]);
103 dsa_words[2] = htonl(words[2]);
104 dsa_words[3] = htonl(words[3]);
105
106 return 0;
107}
108

source code of linux/drivers/net/ethernet/marvell/prestera/prestera_dsa.c