Re: [PATCH 1/1] net/ncsi: add get MAC address command to get Intel i210 MAC address

[Milton Miller II]

On August 30, 2021, Ivan Mikhaylov" <i.mikhaylov@xxxxxxxxx> wrote:
>This patch adds OEM Intel GMA command and response handler for it.



>>>Signed-off-by: Brad Ho <Brad_Ho@xxxxxxxxxxx
>>Signed-off-by: Paul Fertser <fercerpav@xxxxxxxxx>
>Signed-off-by: Ivan Mikhaylov <i.mikhaylov@xxxxxxxxx>
>---
> net/ncsi/internal.h    |  3 +++
> net/ncsi/ncsi-manage.c | 25 ++++++++++++++++++++++++-
> net/ncsi/ncsi-pkt.h    |  6 ++++++
> net/ncsi/ncsi-rsp.c    | 42
>++++++++++++++++++++++++++++++++++++++++++
> 4 files changed, 75 insertions(+), 1 deletion(-)
>
>diff --git a/net/ncsi/internal.h b/net/ncsi/internal.h
>index 0b6cfd3b31e0..03757e76bb6b 100644
>--- a/net/ncsi/internal.h
>+++ b/net/ncsi/internal.h
>@@ -80,6 +80,7 @@ enum {
> #define NCSI_OEM_MFR_BCM_ID             0x113d
> #define NCSI_OEM_MFR_INTEL_ID           0x157
> /* Intel specific OEM command */
>+#define NCSI_OEM_INTEL_CMD_GMA          0x06   /* CMD ID for Get MAC
>*/
> #define NCSI_OEM_INTEL_CMD_KEEP_PHY     0x20   /* CMD ID for Keep
>PHY up */
> /* Broadcom specific OEM Command */
> #define NCSI_OEM_BCM_CMD_GMA            0x01   /* CMD ID for Get MAC
>*/
>@@ -89,6 +90,7 @@ enum {
> #define NCSI_OEM_MLX_CMD_SMAF           0x01   /* CMD ID for Set MC
>Affinity */
> #define NCSI_OEM_MLX_CMD_SMAF_PARAM     0x07   /* Parameter for SMAF
>        */
> /* OEM Command payload lengths*/
>+#define NCSI_OEM_INTEL_CMD_GMA_LEN      5
> #define NCSI_OEM_INTEL_CMD_KEEP_PHY_LEN 7
> #define NCSI_OEM_BCM_CMD_GMA_LEN        12
> #define NCSI_OEM_MLX_CMD_GMA_LEN        8
>@@ -99,6 +101,7 @@ enum {
> /* Mac address offset in OEM response */
> #define BCM_MAC_ADDR_OFFSET             28
> #define MLX_MAC_ADDR_OFFSET             8
>+#define INTEL_MAC_ADDR_OFFSET           1
> 
> 
> struct ncsi_channel_version {
>diff --git a/net/ncsi/ncsi-manage.c b/net/ncsi/ncsi-manage.c
>index 89c7742cd72e..7121ce2a47c0 100644
>--- a/net/ncsi/ncsi-manage.c
>+++ b/net/ncsi/ncsi-manage.c
>@@ -795,13 +795,36 @@ static int ncsi_oem_smaf_mlx(struct
>ncsi_cmd_arg *nca)
> 	return ret;
> }
> 
>+static int ncsi_oem_gma_handler_intel(struct ncsi_cmd_arg *nca)
>+{
>+	unsigned char data[NCSI_OEM_INTEL_CMD_GMA_LEN];
>+	int ret = 0;
>+
>+	nca->payload = NCSI_OEM_INTEL_CMD_GMA_LEN;
>+
>+	memset(data, 0, NCSI_OEM_INTEL_CMD_GMA_LEN);
>+	*(unsigned int *)data = ntohl((__force
>__be32)NCSI_OEM_MFR_INTEL_ID);
>+	data[4] = NCSI_OEM_INTEL_CMD_GMA;
>+
>+	nca->data = data;
>+
>+	ret = ncsi_xmit_cmd(nca);
>+	if (ret)
>+		netdev_err(nca->ndp->ndev.dev,
>+			   "NCSI: Failed to transmit cmd 0x%x during configure\n",
>+			   nca->type);
>+
>+	return ret;
>+}
>+
> /* OEM Command handlers initialization */
> static struct ncsi_oem_gma_handler {
> 	unsigned int	mfr_id;
> 	int		(*handler)(struct ncsi_cmd_arg *nca);
> } ncsi_oem_gma_handlers[] = {
> 	{ NCSI_OEM_MFR_BCM_ID, ncsi_oem_gma_handler_bcm },
>-	{ NCSI_OEM_MFR_MLX_ID, ncsi_oem_gma_handler_mlx }
>+	{ NCSI_OEM_MFR_MLX_ID, ncsi_oem_gma_handler_mlx },
>+	{ NCSI_OEM_MFR_INTEL_ID, ncsi_oem_gma_handler_intel }
> };
> 
> static int ncsi_gma_handler(struct ncsi_cmd_arg *nca, unsigned int
>mf_id)
>diff --git a/net/ncsi/ncsi-pkt.h b/net/ncsi/ncsi-pkt.h
>index 80938b338fee..ba66c7dc3a21 100644
>--- a/net/ncsi/ncsi-pkt.h
>+++ b/net/ncsi/ncsi-pkt.h
>@@ -178,6 +178,12 @@ struct ncsi_rsp_oem_bcm_pkt {
> 	unsigned char           data[];      /* Cmd specific Data */
> };
> 
>+/* Intel Response Data */
>+struct ncsi_rsp_oem_intel_pkt {
>+	unsigned char           cmd;         /* OEM Command ID    */
>+	unsigned char           data[];      /* Cmd specific Data */
>+};
>+
> /* Get Link Status */
> struct ncsi_rsp_gls_pkt {
> 	struct ncsi_rsp_pkt_hdr rsp;        /* Response header   */
>diff --git a/net/ncsi/ncsi-rsp.c b/net/ncsi/ncsi-rsp.c
>index d48374894817..6447a09932f5 100644
>--- a/net/ncsi/ncsi-rsp.c
>+++ b/net/ncsi/ncsi-rsp.c
>@@ -699,9 +699,51 @@ static int ncsi_rsp_handler_oem_bcm(struct
>ncsi_request *nr)
> 	return 0;
> }
> 
>+/* Response handler for Intel command Get Mac Address */
>+static int ncsi_rsp_handler_oem_intel_gma(struct ncsi_request *nr)
>+{
>+	struct ncsi_dev_priv *ndp = nr->ndp;
>+	struct net_device *ndev = ndp->ndev.dev;
>+	const struct net_device_ops *ops = ndev->netdev_ops;
>+	struct ncsi_rsp_oem_pkt *rsp;
>+	struct sockaddr saddr;
>+	int ret = 0;
>+
>+	/* Get the response header */
>+	rsp = (struct ncsi_rsp_oem_pkt *)skb_network_header(nr->rsp);
>+
>+	saddr.sa_family = ndev->type;
>+	ndev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
>+	memcpy(saddr.sa_data, &rsp->data[INTEL_MAC_ADDR_OFFSET], ETH_ALEN);
>+	/* Increase mac address by 1 for BMC's address */
>+	eth_addr_inc((u8 *)saddr.sa_data);
>+	if (!is_valid_ether_addr((const u8 *)saddr.sa_data))
>+		return -ENXIO;

The Intel GMA retireves the MAC address of the host, and the datasheet
anticipates the BMC will "share" the MAC by stealing specific TCP and 
UDP port traffic destined to the host.

This "add one" allocation of the MAC is therefore a policy, and one that 
is beyond the data sheet.

While this +1 policy may work for some OEM boards, there are other boards 
where the MAC address assigned to the BMC does not follow this pattern, 
but instead the MAC is stored in some platform dependent location obtained 
in a platform specific manner.

I suggest this BMC = ether_addr_inc(GMA) be opt in via a device tree property.  

The name of the property should be negotiated in the device tree mailing list, 
as it appears it would be generic to more than one vendor.

Unfortunately, we missed this when we added the broadcom and mellanox handlers.


>+>+	/* Set the flag for GMA command which should only be called once */
>+	ndp->gma_flag = 1;
>+
>+	ret = ops->ndo_set_mac_address(ndev, &saddr);
>+	if (ret < 0)
>+		netdev_warn(ndev,
>+			    "NCSI: 'Writing mac address to device failed\n");
>+
>+	return ret;
>+}
>+
> /* Response handler for Intel card */
> static int ncsi_rsp_handler_oem_intel(struct ncsi_request *nr)
> {
>+	struct ncsi_rsp_oem_intel_pkt *intel;
>+	struct ncsi_rsp_oem_pkt *rsp;
>+
>+	/* Get the response header */
>+	rsp = (struct ncsi_rsp_oem_pkt *)skb_network_header(nr->rsp);
>+	intel = (struct ncsi_rsp_oem_intel_pkt *)(rsp->data);
>+
>+	if (intel->cmd == NCSI_OEM_INTEL_CMD_GMA)
>+		return ncsi_rsp_handler_oem_intel_gma(nr);
>+
> 	return 0;
> }
> 
>-- 
>2.31.1
>
>