target/linux/generic/backport-5.15/776-v6.1-01-net-dsa-qca8k-fix-inband-mgmt-for-big-endian-systems.patch

   1 From a2550d3ce53c68f54042bc5e468c4d07491ffe0e Mon Sep 17 00:00:00 2001
   2 From: Christian Marangi <ansuelsmth@gmail.com>
   3 Date: Wed, 12 Oct 2022 19:18:36 +0200
   4 Subject: [PATCH 1/2] net: dsa: qca8k: fix inband mgmt for big-endian systems
   5
   6 The header and the data of the skb for the inband mgmt requires
   7 to be in little-endian. This is problematic for big-endian system
   8 as the mgmt header is written in the cpu byte order.
   9
  10 Fix this by converting each value for the mgmt header and data to
  11 little-endian, and convert to cpu byte order the mgmt header and
  12 data sent by the switch.
  13
  14 Fixes: 5950c7c0a68c ("net: dsa: qca8k: add support for mgmt read/write in Ethernet packet")
  15 Tested-by: Pawel Dembicki <paweldembicki@gmail.com>
  16 Tested-by: Lech Perczak <lech.perczak@gmail.com>
  17 Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
  18 Reviewed-by: Lech Perczak <lech.perczak@gmail.com>
  19 Signed-off-by: David S. Miller <davem@davemloft.net>
  20 ---
  21  drivers/net/dsa/qca/qca8k-8xxx.c | 63 ++++++++++++++++++++++++--------
  22  include/linux/dsa/tag_qca.h      |  6 +--
  23  2 files changed, 50 insertions(+), 19 deletions(-)
  24
  25 --- a/drivers/net/dsa/qca/qca8k-8xxx.c
  26 +++ b/drivers/net/dsa/qca/qca8k-8xxx.c
  27 @@ -137,27 +137,42 @@ static void qca8k_rw_reg_ack_handler(str
  28         struct qca8k_mgmt_eth_data *mgmt_eth_data;
  29         struct qca8k_priv *priv = ds->priv;
  30         struct qca_mgmt_ethhdr *mgmt_ethhdr;
  31 +       u32 command;
  32         u8 len, cmd;
  33 +       int i;
  34
  35         mgmt_ethhdr = (struct qca_mgmt_ethhdr *)skb_mac_header(skb);
  36         mgmt_eth_data = &priv->mgmt_eth_data;
  37
  38 -       cmd = FIELD_GET(QCA_HDR_MGMT_CMD, mgmt_ethhdr->command);
  39 -       len = FIELD_GET(QCA_HDR_MGMT_LENGTH, mgmt_ethhdr->command);
  40 +       command = get_unaligned_le32(&mgmt_ethhdr->command);
  41 +       cmd = FIELD_GET(QCA_HDR_MGMT_CMD, command);
  42 +       len = FIELD_GET(QCA_HDR_MGMT_LENGTH, command);
  43
  44         /* Make sure the seq match the requested packet */
  45 -       if (mgmt_ethhdr->seq == mgmt_eth_data->seq)
  46 +       if (get_unaligned_le32(&mgmt_ethhdr->seq) == mgmt_eth_data->seq)
  47                 mgmt_eth_data->ack = true;
  48
  49         if (cmd == MDIO_READ) {
  50 -               mgmt_eth_data->data[0] = mgmt_ethhdr->mdio_data;
  51 +               u32 *val = mgmt_eth_data->data;
  52 +
  53 +               *val = get_unaligned_le32(&mgmt_ethhdr->mdio_data);
  54
  55                 /* Get the rest of the 12 byte of data.
  56                  * The read/write function will extract the requested data.
  57                  */
  58 -               if (len > QCA_HDR_MGMT_DATA1_LEN)
  59 -                       memcpy(mgmt_eth_data->data + 1, skb->data,
  60 -                              QCA_HDR_MGMT_DATA2_LEN);
  61 +               if (len > QCA_HDR_MGMT_DATA1_LEN) {
  62 +                       __le32 *data2 = (__le32 *)skb->data;
  63 +                       int data_len = min_t(int, QCA_HDR_MGMT_DATA2_LEN,
  64 +                                            len - QCA_HDR_MGMT_DATA1_LEN);
  65 +
  66 +                       val++;
  67 +
  68 +                       for (i = sizeof(u32); i <= data_len; i += sizeof(u32)) {
  69 +                               *val = get_unaligned_le32(data2);
  70 +                               val++;
  71 +                               data2++;
  72 +                       }
  73 +               }
  74         }
  75
  76         complete(&mgmt_eth_data->rw_done);
  77 @@ -169,8 +184,10 @@ static struct sk_buff *qca8k_alloc_mdio_
  78         struct qca_mgmt_ethhdr *mgmt_ethhdr;
  79         unsigned int real_len;
  80         struct sk_buff *skb;
  81 -       u32 *data2;
  82 +       __le32 *data2;
  83 +       u32 command;
  84         u16 hdr;
  85 +       int i;
  86
  87         skb = dev_alloc_skb(QCA_HDR_MGMT_PKT_LEN);
  88         if (!skb)
  89 @@ -199,20 +216,32 @@ static struct sk_buff *qca8k_alloc_mdio_
  90         hdr |= FIELD_PREP(QCA_HDR_XMIT_DP_BIT, BIT(0));
  91         hdr |= FIELD_PREP(QCA_HDR_XMIT_CONTROL, QCA_HDR_XMIT_TYPE_RW_REG);
  92
  93 -       mgmt_ethhdr->command = FIELD_PREP(QCA_HDR_MGMT_ADDR, reg);
  94 -       mgmt_ethhdr->command |= FIELD_PREP(QCA_HDR_MGMT_LENGTH, real_len);
  95 -       mgmt_ethhdr->command |= FIELD_PREP(QCA_HDR_MGMT_CMD, cmd);
  96 -       mgmt_ethhdr->command |= FIELD_PREP(QCA_HDR_MGMT_CHECK_CODE,
  97 +       command = FIELD_PREP(QCA_HDR_MGMT_ADDR, reg);
  98 +       command |= FIELD_PREP(QCA_HDR_MGMT_LENGTH, real_len);
  99 +       command |= FIELD_PREP(QCA_HDR_MGMT_CMD, cmd);
 100 +       command |= FIELD_PREP(QCA_HDR_MGMT_CHECK_CODE,
 101                                            QCA_HDR_MGMT_CHECK_CODE_VAL);
 102
 103 +       put_unaligned_le32(command, &mgmt_ethhdr->command);
 104 +
 105         if (cmd == MDIO_WRITE)
 106 -               mgmt_ethhdr->mdio_data = *val;
 107 +               put_unaligned_le32(*val, &mgmt_ethhdr->mdio_data);
 108
 109         mgmt_ethhdr->hdr = htons(hdr);
 110
 111         data2 = skb_put_zero(skb, QCA_HDR_MGMT_DATA2_LEN + QCA_HDR_MGMT_PADDING_LEN);
 112 -       if (cmd == MDIO_WRITE && len > QCA_HDR_MGMT_DATA1_LEN)
 113 -               memcpy(data2, val + 1, len - QCA_HDR_MGMT_DATA1_LEN);
 114 +       if (cmd == MDIO_WRITE && len > QCA_HDR_MGMT_DATA1_LEN) {
 115 +               int data_len = min_t(int, QCA_HDR_MGMT_DATA2_LEN,
 116 +                                    len - QCA_HDR_MGMT_DATA1_LEN);
 117 +
 118 +               val++;
 119 +
 120 +               for (i = sizeof(u32); i <= data_len; i += sizeof(u32)) {
 121 +                       put_unaligned_le32(*val, data2);
 122 +                       data2++;
 123 +                       val++;
 124 +               }
 125 +       }
 126
 127         return skb;
 128  }
 129 @@ -220,9 +249,11 @@ static struct sk_buff *qca8k_alloc_mdio_
 130  static void qca8k_mdio_header_fill_seq_num(struct sk_buff *skb, u32 seq_num)
 131  {
 132         struct qca_mgmt_ethhdr *mgmt_ethhdr;
 133 +       u32 seq;
 134
 135 +       seq = FIELD_PREP(QCA_HDR_MGMT_SEQ_NUM, seq_num);
 136         mgmt_ethhdr = (struct qca_mgmt_ethhdr *)skb->data;
 137 -       mgmt_ethhdr->seq = FIELD_PREP(QCA_HDR_MGMT_SEQ_NUM, seq_num);
 138 +       put_unaligned_le32(seq, &mgmt_ethhdr->seq);
 139  }
 140
 141  static int qca8k_read_eth(struct qca8k_priv *priv, u32 reg, u32 *val, int len)
 142 --- a/include/linux/dsa/tag_qca.h
 143 +++ b/include/linux/dsa/tag_qca.h
 144 @@ -56,9 +56,9 @@
 145
 146  /* Special struct emulating a Ethernet header */
 147  struct qca_mgmt_ethhdr {
 148 -       u32 command;            /* command bit 31:0 */
 149 -       u32 seq;                /* seq 63:32 */
 150 -       u32 mdio_data;          /* first 4byte mdio */
 151 +       __le32 command;         /* command bit 31:0 */
 152 +       __le32 seq;             /* seq 63:32 */
 153 +       __le32 mdio_data;               /* first 4byte mdio */
 154         __be16 hdr;             /* qca hdr */
 155  } __packed;
 156