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 diff --git a/drivers/net/dsa/qca/qca8k-8xxx.c b/drivers/net/dsa/qca/qca8k-8xxx.c
  26 index 5669c92c93f7..644338ca0510 100644
  27 --- a/drivers/net/dsa/qca/qca8k-8xxx.c
  28 +++ b/drivers/net/dsa/qca/qca8k-8xxx.c
  29 @@ -137,27 +137,42 @@ static void qca8k_rw_reg_ack_handler(struct dsa_switch *ds, struct sk_buff *skb)
  30         struct qca8k_mgmt_eth_data *mgmt_eth_data;
  31         struct qca8k_priv *priv = ds->priv;
  32         struct qca_mgmt_ethhdr *mgmt_ethhdr;
  33 +       u32 command;
  34         u8 len, cmd;
  35 +       int i;
  36
  37         mgmt_ethhdr = (struct qca_mgmt_ethhdr *)skb_mac_header(skb);
  38         mgmt_eth_data = &priv->mgmt_eth_data;
  39
  40 -       cmd = FIELD_GET(QCA_HDR_MGMT_CMD, mgmt_ethhdr->command);
  41 -       len = FIELD_GET(QCA_HDR_MGMT_LENGTH, mgmt_ethhdr->command);
  42 +       command = get_unaligned_le32(&mgmt_ethhdr->command);
  43 +       cmd = FIELD_GET(QCA_HDR_MGMT_CMD, command);
  44 +       len = FIELD_GET(QCA_HDR_MGMT_LENGTH, command);
  45
  46         /* Make sure the seq match the requested packet */
  47 -       if (mgmt_ethhdr->seq == mgmt_eth_data->seq)
  48 +       if (get_unaligned_le32(&mgmt_ethhdr->seq) == mgmt_eth_data->seq)
  49                 mgmt_eth_data->ack = true;
  50
  51         if (cmd == MDIO_READ) {
  52 -               mgmt_eth_data->data[0] = mgmt_ethhdr->mdio_data;
  53 +               u32 *val = mgmt_eth_data->data;
  54 +
  55 +               *val = get_unaligned_le32(&mgmt_ethhdr->mdio_data);
  56
  57                 /* Get the rest of the 12 byte of data.
  58                  * The read/write function will extract the requested data.
  59                  */
  60 -               if (len > QCA_HDR_MGMT_DATA1_LEN)
  61 -                       memcpy(mgmt_eth_data->data + 1, skb->data,
  62 -                              QCA_HDR_MGMT_DATA2_LEN);
  63 +               if (len > QCA_HDR_MGMT_DATA1_LEN) {
  64 +                       __le32 *data2 = (__le32 *)skb->data;
  65 +                       int data_len = min_t(int, QCA_HDR_MGMT_DATA2_LEN,
  66 +                                            len - QCA_HDR_MGMT_DATA1_LEN);
  67 +
  68 +                       val++;
  69 +
  70 +                       for (i = sizeof(u32); i <= data_len; i += sizeof(u32)) {
  71 +                               *val = get_unaligned_le32(data2);
  72 +                               val++;
  73 +                               data2++;
  74 +                       }
  75 +               }
  76         }
  77
  78         complete(&mgmt_eth_data->rw_done);
  79 @@ -169,8 +184,10 @@ static struct sk_buff *qca8k_alloc_mdio_header(enum mdio_cmd cmd, u32 reg, u32 *
  80         struct qca_mgmt_ethhdr *mgmt_ethhdr;
  81         unsigned int real_len;
  82         struct sk_buff *skb;
  83 -       u32 *data2;
  84 +       __le32 *data2;
  85 +       u32 command;
  86         u16 hdr;
  87 +       int i;
  88
  89         skb = dev_alloc_skb(QCA_HDR_MGMT_PKT_LEN);
  90         if (!skb)
  91 @@ -199,20 +216,32 @@ static struct sk_buff *qca8k_alloc_mdio_header(enum mdio_cmd cmd, u32 reg, u32 *
  92         hdr |= FIELD_PREP(QCA_HDR_XMIT_DP_BIT, BIT(0));
  93         hdr |= FIELD_PREP(QCA_HDR_XMIT_CONTROL, QCA_HDR_XMIT_TYPE_RW_REG);
  94
  95 -       mgmt_ethhdr->command = FIELD_PREP(QCA_HDR_MGMT_ADDR, reg);
  96 -       mgmt_ethhdr->command |= FIELD_PREP(QCA_HDR_MGMT_LENGTH, real_len);
  97 -       mgmt_ethhdr->command |= FIELD_PREP(QCA_HDR_MGMT_CMD, cmd);
  98 -       mgmt_ethhdr->command |= FIELD_PREP(QCA_HDR_MGMT_CHECK_CODE,
  99 +       command = FIELD_PREP(QCA_HDR_MGMT_ADDR, reg);
 100 +       command |= FIELD_PREP(QCA_HDR_MGMT_LENGTH, real_len);
 101 +       command |= FIELD_PREP(QCA_HDR_MGMT_CMD, cmd);
 102 +       command |= FIELD_PREP(QCA_HDR_MGMT_CHECK_CODE,
 103                                            QCA_HDR_MGMT_CHECK_CODE_VAL);
 104
 105 +       put_unaligned_le32(command, &mgmt_ethhdr->command);
 106 +
 107         if (cmd == MDIO_WRITE)
 108 -               mgmt_ethhdr->mdio_data = *val;
 109 +               put_unaligned_le32(*val, &mgmt_ethhdr->mdio_data);
 110
 111         mgmt_ethhdr->hdr = htons(hdr);
 112
 113         data2 = skb_put_zero(skb, QCA_HDR_MGMT_DATA2_LEN + QCA_HDR_MGMT_PADDING_LEN);
 114 -       if (cmd == MDIO_WRITE && len > QCA_HDR_MGMT_DATA1_LEN)
 115 -               memcpy(data2, val + 1, len - QCA_HDR_MGMT_DATA1_LEN);
 116 +       if (cmd == MDIO_WRITE && len > QCA_HDR_MGMT_DATA1_LEN) {
 117 +               int data_len = min_t(int, QCA_HDR_MGMT_DATA2_LEN,
 118 +                                    len - QCA_HDR_MGMT_DATA1_LEN);
 119 +
 120 +               val++;
 121 +
 122 +               for (i = sizeof(u32); i <= data_len; i += sizeof(u32)) {
 123 +                       put_unaligned_le32(*val, data2);
 124 +                       data2++;
 125 +                       val++;
 126 +               }
 127 +       }
 128
 129         return skb;
 130  }
 131 @@ -220,9 +249,11 @@ static struct sk_buff *qca8k_alloc_mdio_header(enum mdio_cmd cmd, u32 reg, u32 *
 132  static void qca8k_mdio_header_fill_seq_num(struct sk_buff *skb, u32 seq_num)
 133  {
 134         struct qca_mgmt_ethhdr *mgmt_ethhdr;
 135 +       u32 seq;
 136
 137 +       seq = FIELD_PREP(QCA_HDR_MGMT_SEQ_NUM, seq_num);
 138         mgmt_ethhdr = (struct qca_mgmt_ethhdr *)skb->data;
 139 -       mgmt_ethhdr->seq = FIELD_PREP(QCA_HDR_MGMT_SEQ_NUM, seq_num);
 140 +       put_unaligned_le32(seq, &mgmt_ethhdr->seq);
 141  }
 142
 143  static int qca8k_read_eth(struct qca8k_priv *priv, u32 reg, u32 *val, int len)
 144 diff --git a/include/linux/dsa/tag_qca.h b/include/linux/dsa/tag_qca.h
 145 index 50be7cbd93a5..0e176da1e43f 100644
 146 --- a/include/linux/dsa/tag_qca.h
 147 +++ b/include/linux/dsa/tag_qca.h
 148 @@ -61,9 +61,9 @@ struct sk_buff;
 149
 150  /* Special struct emulating a Ethernet header */
 151  struct qca_mgmt_ethhdr {
 152 -       u32 command;            /* command bit 31:0 */
 153 -       u32 seq;                /* seq 63:32 */
 154 -       u32 mdio_data;          /* first 4byte mdio */
 155 +       __le32 command;         /* command bit 31:0 */
 156 +       __le32 seq;             /* seq 63:32 */
 157 +       __le32 mdio_data;               /* first 4byte mdio */
 158         __be16 hdr;             /* qca hdr */
 159  } __packed;
 160
 161 --
 162 2.37.2
 163