drivers/net/ethernet/netronome/nfp/nfp_net_ctrl.c

   1 /*
   2  * Copyright (C) 2018 Netronome Systems, Inc.
   3  *
   4  * This software is dual licensed under the GNU General License Version 2,
   5  * June 1991 as shown in the file COPYING in the top-level directory of this
   6  * source tree or the BSD 2-Clause License provided below.  You have the
   7  * option to license this software under the complete terms of either license.
   8  *
   9  * The BSD 2-Clause License:
  10  *
  11  *     Redistribution and use in source and binary forms, with or
  12  *     without modification, are permitted provided that the following
  13  *     conditions are met:
  14  *
  15  *      1. Redistributions of source code must retain the above
  16  *         copyright notice, this list of conditions and the following
  17  *         disclaimer.
  18  *
  19  *      2. Redistributions in binary form must reproduce the above
  20  *         copyright notice, this list of conditions and the following
  21  *         disclaimer in the documentation and/or other materials
  22  *         provided with the distribution.
  23  *
  24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  28  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  29  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  30  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  31  * SOFTWARE.
  32  */
  33
  34 #include <linux/bitfield.h>
  35 #include <linux/device.h>
  36 #include <linux/kernel.h>
  37 #include <linux/types.h>
  38
  39 #include "nfp_net_ctrl.h"
  40 #include "nfp_net.h"
  41
  42 static void nfp_net_tlv_caps_reset(struct nfp_net_tlv_caps *caps)
  43 {
  44         memset(caps, 0, sizeof(*caps));
  45         caps->me_freq_mhz = 1200;
  46         caps->mbox_off = NFP_NET_CFG_MBOX_BASE;
  47         caps->mbox_len = NFP_NET_CFG_MBOX_VAL_MAX_SZ;
  48 }
  49
  50 int nfp_net_tlv_caps_parse(struct device *dev, u8 __iomem *ctrl_mem,
  51                            struct nfp_net_tlv_caps *caps)
  52 {
  53         u8 __iomem *data = ctrl_mem + NFP_NET_CFG_TLV_BASE;
  54         u8 __iomem *end = ctrl_mem + NFP_NET_CFG_BAR_SZ;
  55         u32 hdr;
  56
  57         nfp_net_tlv_caps_reset(caps);
  58
  59         hdr = readl(data);
  60         if (!hdr)
  61                 return 0;
  62
  63         while (true) {
  64                 unsigned int length, offset;
  65                 u32 hdr = readl(data);
  66
  67                 length = FIELD_GET(NFP_NET_CFG_TLV_HEADER_LENGTH, hdr);
  68                 offset = data - ctrl_mem;
  69
  70                 /* Advance past the header */
  71                 data += 4;
  72
  73                 if (length % NFP_NET_CFG_TLV_LENGTH_INC) {
  74                         dev_err(dev, "TLV size not multiple of %u len:%u\n",
  75                                 NFP_NET_CFG_TLV_LENGTH_INC, length);
  76                         return -EINVAL;
  77                 }
  78                 if (data + length > end) {
  79                         dev_err(dev, "oversized TLV offset:%u len:%u\n",
  80                                 offset, length);
  81                         return -EINVAL;
  82                 }
  83
  84                 switch (FIELD_GET(NFP_NET_CFG_TLV_HEADER_TYPE, hdr)) {
  85                 case NFP_NET_CFG_TLV_TYPE_UNKNOWN:
  86                         dev_err(dev, "NULL TLV at offset:%u\n", offset);
  87                         return -EINVAL;
  88                 case NFP_NET_CFG_TLV_TYPE_RESERVED:
  89                         break;
  90                 case NFP_NET_CFG_TLV_TYPE_END:
  91                         if (!length)
  92                                 return 0;
  93
  94                         dev_err(dev, "END TLV should be empty, has len:%d\n",
  95                                 length);
  96                         return -EINVAL;
  97                 case NFP_NET_CFG_TLV_TYPE_ME_FREQ:
  98                         if (length != 4) {
  99                                 dev_err(dev,
 100                                         "ME FREQ TLV should be 4B, is %dB\n",
 101                                         length);
 102                                 return -EINVAL;
 103                         }
 104
 105                         caps->me_freq_mhz = readl(data);
 106                         break;
 107                 case NFP_NET_CFG_TLV_TYPE_MBOX:
 108                         if (!length) {
 109                                 caps->mbox_off = 0;
 110                                 caps->mbox_len = 0;
 111                         } else {
 112                                 caps->mbox_off = data - ctrl_mem;
 113                                 caps->mbox_len = length;
 114                         }
 115                         break;
 116                 default:
 117                         if (!FIELD_GET(NFP_NET_CFG_TLV_HEADER_REQUIRED, hdr))
 118                                 break;
 119
 120                         dev_err(dev, "unknown TLV type:%u offset:%u len:%u\n",
 121                                 FIELD_GET(NFP_NET_CFG_TLV_HEADER_TYPE, hdr),
 122                                 offset, length);
 123                         return -EINVAL;
 124                 }
 125
 126                 data += length;
 127                 if (data + 4 > end) {
 128                         dev_err(dev, "reached end of BAR without END TLV\n");
 129                         return -EINVAL;
 130                 }
 131         }
 132
 133         /* Not reached */
 134         return -EINVAL;
 135 }