git.openwrt.org Git - openwrt/openwrt.git/blob

   1 From c2ee8181fddb293d296477f60b3eb4fa3ce4e1a6 Mon Sep 17 00:00:00 2001
   2 From: Ansuel Smith <ansuelsmth@gmail.com>
   3 Date: Wed, 2 Feb 2022 01:03:25 +0100
   4 Subject: [PATCH 06/16] net: dsa: tag_qca: add define for handling mgmt
   5  Ethernet packet
   6
   7 Add all the required define to prepare support for mgmt read/write in
   8 Ethernet packet. Any packet of this type has to be dropped as the only
   9 use of these special packet is receive ack for an mgmt write request or
  10 receive data for an mgmt read request.
  11 A struct is used that emulates the Ethernet header but is used for a
  12 different purpose.
  13
  14 Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
  15 Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
  16 Signed-off-by: David S. Miller <davem@davemloft.net>
  17 ---
  18  include/linux/dsa/tag_qca.h | 44 +++++++++++++++++++++++++++++++++++++
  19  net/dsa/tag_qca.c           | 15 ++++++++++---
  20  2 files changed, 56 insertions(+), 3 deletions(-)
  21
  22 diff --git a/include/linux/dsa/tag_qca.h b/include/linux/dsa/tag_qca.h
  23 index c02d2d39ff4a..f366422ab7a0 100644
  24 --- a/include/linux/dsa/tag_qca.h
  25 +++ b/include/linux/dsa/tag_qca.h
  26 @@ -12,10 +12,54 @@
  27  #define QCA_HDR_RECV_FRAME_IS_TAGGED   BIT(3)
  28  #define QCA_HDR_RECV_SOURCE_PORT       GENMASK(2, 0)
  29
  30 +/* Packet type for recv */
  31 +#define QCA_HDR_RECV_TYPE_NORMAL       0x0
  32 +#define QCA_HDR_RECV_TYPE_MIB          0x1
  33 +#define QCA_HDR_RECV_TYPE_RW_REG_ACK   0x2
  34 +
  35  #define QCA_HDR_XMIT_VERSION           GENMASK(15, 14)
  36  #define QCA_HDR_XMIT_PRIORITY          GENMASK(13, 11)
  37  #define QCA_HDR_XMIT_CONTROL           GENMASK(10, 8)
  38  #define QCA_HDR_XMIT_FROM_CPU          BIT(7)
  39  #define QCA_HDR_XMIT_DP_BIT            GENMASK(6, 0)
  40
  41 +/* Packet type for xmit */
  42 +#define QCA_HDR_XMIT_TYPE_NORMAL       0x0
  43 +#define QCA_HDR_XMIT_TYPE_RW_REG       0x1
  44 +
  45 +/* Check code for a valid mgmt packet. Switch will ignore the packet
  46 + * with this wrong.
  47 + */
  48 +#define QCA_HDR_MGMT_CHECK_CODE_VAL    0x5
  49 +
  50 +/* Specific define for in-band MDIO read/write with Ethernet packet */
  51 +#define QCA_HDR_MGMT_SEQ_LEN           4 /* 4 byte for the seq */
  52 +#define QCA_HDR_MGMT_COMMAND_LEN       4 /* 4 byte for the command */
  53 +#define QCA_HDR_MGMT_DATA1_LEN         4 /* First 4 byte for the mdio data */
  54 +#define QCA_HDR_MGMT_HEADER_LEN                (QCA_HDR_MGMT_SEQ_LEN + \
  55 +                                       QCA_HDR_MGMT_COMMAND_LEN + \
  56 +                                       QCA_HDR_MGMT_DATA1_LEN)
  57 +
  58 +#define QCA_HDR_MGMT_DATA2_LEN         12 /* Other 12 byte for the mdio data */
  59 +#define QCA_HDR_MGMT_PADDING_LEN       34 /* Padding to reach the min Ethernet packet */
  60 +
  61 +#define QCA_HDR_MGMT_PKT_LEN           (QCA_HDR_MGMT_HEADER_LEN + \
  62 +                                       QCA_HDR_LEN + \
  63 +                                       QCA_HDR_MGMT_DATA2_LEN + \
  64 +                                       QCA_HDR_MGMT_PADDING_LEN)
  65 +
  66 +#define QCA_HDR_MGMT_SEQ_NUM           GENMASK(31, 0)  /* 63, 32 */
  67 +#define QCA_HDR_MGMT_CHECK_CODE                GENMASK(31, 29) /* 31, 29 */
  68 +#define QCA_HDR_MGMT_CMD               BIT(28)         /* 28 */
  69 +#define QCA_HDR_MGMT_LENGTH            GENMASK(23, 20) /* 23, 20 */
  70 +#define QCA_HDR_MGMT_ADDR              GENMASK(18, 0)  /* 18, 0 */
  71 +
  72 +/* Special struct emulating a Ethernet header */
  73 +struct qca_mgmt_ethhdr {
  74 +       u32 command;            /* command bit 31:0 */
  75 +       u32 seq;                /* seq 63:32 */
  76 +       u32 mdio_data;          /* first 4byte mdio */
  77 +       __be16 hdr;             /* qca hdr */
  78 +} __packed;
  79 +
  80  #endif /* __TAG_QCA_H */
  81 diff --git a/net/dsa/tag_qca.c b/net/dsa/tag_qca.c
  82 index f8df49d5956f..f17ed5be20c2 100644
  83 --- a/net/dsa/tag_qca.c
  84 +++ b/net/dsa/tag_qca.c
  85 @@ -32,10 +32,12 @@ static struct sk_buff *qca_tag_xmit(struct sk_buff *skb, struct net_device *dev)
  86
  87  static struct sk_buff *qca_tag_rcv(struct sk_buff *skb, struct net_device *dev)
  88  {
  89 -       u8 ver;
  90 -       u16  hdr;
  91 -       int port;
  92 +       u8 ver, pk_type;
  93         __be16 *phdr;
  94 +       int port;
  95 +       u16 hdr;
  96 +
  97 +       BUILD_BUG_ON(sizeof(struct qca_mgmt_ethhdr) != QCA_HDR_MGMT_HEADER_LEN + QCA_HDR_LEN);
  98
  99         if (unlikely(!pskb_may_pull(skb, QCA_HDR_LEN)))
 100                 return NULL;
 101 @@ -48,6 +50,13 @@ static struct sk_buff *qca_tag_rcv(struct sk_buff *skb, struct net_device *dev)
 102         if (unlikely(ver != QCA_HDR_VERSION))
 103                 return NULL;
 104
 105 +       /* Get pk type */
 106 +       pk_type = FIELD_GET(QCA_HDR_RECV_TYPE, hdr);
 107 +
 108 +       /* Ethernet MDIO read/write packet */
 109 +       if (pk_type == QCA_HDR_RECV_TYPE_RW_REG_ACK)
 110 +               return NULL;
 111 +
 112         /* Remove QCA tag and recalculate checksum */
 113         skb_pull_rcsum(skb, QCA_HDR_LEN);
 114         dsa_strip_etype_header(skb, QCA_HDR_LEN);
 115 --
 116 2.34.1
 117