[PATCH 3/3] net/ncsi: Add NC-SI 1.2 Get MC MAC Address command

From: Peter Delevoryas
Date: Wed Dec 21 2022 - 00:23:12 EST


This change adds support for the NC-SI 1.2 Get MC MAC Address command,
specified here:

https://www.dmtf.org/sites/default/files/standards/documents/DSP0222_1.2WIP90_0.pdf

It serves the exact same function as the existing OEM Get MAC Address
commands, so if a channel reports that it supports NC-SI 1.2, we prefer
to use the standard command rather than the OEM command.

Verified with an invalid MAC address and 2 valid ones:

[ 55.137072] ftgmac100 1e690000.ftgmac eth0: NCSI: Received 3 provisioned MAC addresses
[ 55.137614] ftgmac100 1e690000.ftgmac eth0: NCSI: MAC address 0: 00:00:00:00:00:00
[ 55.138026] ftgmac100 1e690000.ftgmac eth0: NCSI: MAC address 1: fa:ce:b0:0c:20:22
[ 55.138528] ftgmac100 1e690000.ftgmac eth0: NCSI: MAC address 2: fa:ce:b0:0c:20:23
[ 55.139241] ftgmac100 1e690000.ftgmac eth0: NCSI: Unable to assign 00:00:00:00:00:00 to device
[ 55.140098] ftgmac100 1e690000.ftgmac eth0: NCSI: Set MAC address to fa:ce:b0:0c:20:22

IMPORTANT NOTE:

The code I'm submitting here is parsing the MAC addresses as if they are
transmitted in *reverse* order.

This is different from how every other NC-SI command is parsed in the
Linux kernel, even though the spec describes the format in the same way
for every command.

The *reason* for this is that I was able to test this code against the
new 200G Broadcom NIC, which reports that it supports NC-SI 1.2 in Get
Version ID and successfully responds to this command. It transmits the
MAC addresses in reverse byte order.

Nvidia's new 200G NIC doesn't support NC-SI 1.2 yet. I don't know how
they're planning to implement it.

Why did Broadcom do this? Well, they have some of the core NC-SI
specification maintainers there, and at some point they must have
decided that everyone (Linux kernel folks and Nvidia and previous
Broadcom firmware authors) is interpreting the specification
incorrectly. They created a 2nd edition of their OEM Get MAC Address
command that returns the MAC address in reverse order:

https://github.com/facebook/openbmc-linux/commit/a4a3a45809c6d43582a12a25bc45b95a79a4c034

That was never upstreamed, but it's supposed to replace the version we
have in the upstream 6.x kernel today.

So, to summarize: I chose the reverse encoding because that's what the
first NC-SI 1.2 supported NIC is doing, and apparently that might be the
correct way to interpret the spec as we go forward.

Signed-off-by: Peter Delevoryas <peter@xxxxxxx>
---
net/ncsi/ncsi-cmd.c | 3 ++-
net/ncsi/ncsi-manage.c | 9 +++++++--
net/ncsi/ncsi-pkt.h | 10 ++++++++++
net/ncsi/ncsi-rsp.c | 45 +++++++++++++++++++++++++++++++++++++++++-
4 files changed, 63 insertions(+), 4 deletions(-)

diff --git a/net/ncsi/ncsi-cmd.c b/net/ncsi/ncsi-cmd.c
index dda8b76b7798..7be177f55173 100644
--- a/net/ncsi/ncsi-cmd.c
+++ b/net/ncsi/ncsi-cmd.c
@@ -269,7 +269,8 @@ static struct ncsi_cmd_handler {
{ NCSI_PKT_CMD_GPS, 0, ncsi_cmd_handler_default },
{ NCSI_PKT_CMD_OEM, -1, ncsi_cmd_handler_oem },
{ NCSI_PKT_CMD_PLDM, 0, NULL },
- { NCSI_PKT_CMD_GPUUID, 0, ncsi_cmd_handler_default }
+ { NCSI_PKT_CMD_GPUUID, 0, ncsi_cmd_handler_default },
+ { NCSI_PKT_CMD_GMCMA, 0, ncsi_cmd_handler_default }
};

static struct ncsi_request *ncsi_alloc_command(struct ncsi_cmd_arg *nca)
diff --git a/net/ncsi/ncsi-manage.c b/net/ncsi/ncsi-manage.c
index f56795769893..bc1887a2543d 100644
--- a/net/ncsi/ncsi-manage.c
+++ b/net/ncsi/ncsi-manage.c
@@ -1038,11 +1038,16 @@ static void ncsi_configure_channel(struct ncsi_dev_priv *ndp)
case ncsi_dev_state_config_oem_gma:
nd->state = ncsi_dev_state_config_clear_vids;

- nca.type = NCSI_PKT_CMD_OEM;
nca.package = np->id;
nca.channel = nc->id;
ndp->pending_req_num = 1;
- ret = ncsi_gma_handler(&nca, nc->version.mf_id);
+ if (nc->version.major >= 1 && nc->version.minor >= 2) {
+ nca.type = NCSI_PKT_CMD_GMCMA;
+ ret = ncsi_xmit_cmd(&nca);
+ } else {
+ nca.type = NCSI_PKT_CMD_OEM;
+ ret = ncsi_gma_handler(&nca, nc->version.mf_id);
+ }
if (ret < 0)
schedule_work(&ndp->work);

diff --git a/net/ncsi/ncsi-pkt.h b/net/ncsi/ncsi-pkt.h
index c9d1da34dc4d..f2f3b5c1b941 100644
--- a/net/ncsi/ncsi-pkt.h
+++ b/net/ncsi/ncsi-pkt.h
@@ -338,6 +338,14 @@ struct ncsi_rsp_gpuuid_pkt {
__be32 checksum;
};

+/* Get MC MAC Address */
+struct ncsi_rsp_gmcma_pkt {
+ struct ncsi_rsp_pkt_hdr rsp;
+ unsigned char address_count;
+ unsigned char reserved[3];
+ unsigned char addresses[][ETH_ALEN];
+};
+
/* AEN: Link State Change */
struct ncsi_aen_lsc_pkt {
struct ncsi_aen_pkt_hdr aen; /* AEN header */
@@ -398,6 +406,7 @@ struct ncsi_aen_hncdsc_pkt {
#define NCSI_PKT_CMD_GPUUID 0x52 /* Get package UUID */
#define NCSI_PKT_CMD_QPNPR 0x56 /* Query Pending NC PLDM request */
#define NCSI_PKT_CMD_SNPR 0x57 /* Send NC PLDM Reply */
+#define NCSI_PKT_CMD_GMCMA 0x58 /* Get MC MAC Address */


/* NCSI packet responses */
@@ -433,6 +442,7 @@ struct ncsi_aen_hncdsc_pkt {
#define NCSI_PKT_RSP_GPUUID (NCSI_PKT_CMD_GPUUID + 0x80)
#define NCSI_PKT_RSP_QPNPR (NCSI_PKT_CMD_QPNPR + 0x80)
#define NCSI_PKT_RSP_SNPR (NCSI_PKT_CMD_SNPR + 0x80)
+#define NCSI_PKT_RSP_GMCMA (NCSI_PKT_CMD_GMCMA + 0x80)

/* NCSI response code/reason */
#define NCSI_PKT_RSP_C_COMPLETED 0x0000 /* Command Completed */
diff --git a/net/ncsi/ncsi-rsp.c b/net/ncsi/ncsi-rsp.c
index 7a805b86a12d..28a042688d0b 100644
--- a/net/ncsi/ncsi-rsp.c
+++ b/net/ncsi/ncsi-rsp.c
@@ -1140,6 +1140,48 @@ static int ncsi_rsp_handler_netlink(struct ncsi_request *nr)
return ret;
}

+static int ncsi_rsp_handler_gmcma(struct ncsi_request *nr)
+{
+ struct ncsi_dev_priv *ndp = nr->ndp;
+ struct net_device *ndev = ndp->ndev.dev;
+ struct ncsi_rsp_gmcma_pkt *rsp;
+ struct sockaddr saddr;
+ int ret = -1;
+ int i;
+ int j;
+
+ rsp = (struct ncsi_rsp_gmcma_pkt *)skb_network_header(nr->rsp);
+ saddr.sa_family = ndev->type;
+ ndev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
+
+ netdev_warn(ndev, "NCSI: Received %d provisioned MAC addresses\n",
+ rsp->address_count);
+ for (i = 0; i < rsp->address_count; i++) {
+ netdev_warn(ndev, "NCSI: MAC address %d: "
+ "%02x:%02x:%02x:%02x:%02x:%02x\n", i,
+ rsp->addresses[i][5], rsp->addresses[i][4],
+ rsp->addresses[i][3], rsp->addresses[i][2],
+ rsp->addresses[i][1], rsp->addresses[i][0]);
+ }
+
+ for (i = 0; i < rsp->address_count; i++) {
+ for (j = 0; j < ETH_ALEN; j++) {
+ saddr.sa_data[j] = rsp->addresses[i][ETH_ALEN - j - 1];
+ }
+ ret = ndev->netdev_ops->ndo_set_mac_address(ndev, &saddr);
+ if (ret < 0) {
+ netdev_warn(ndev, "NCSI: Unable to assign %pM to "
+ "device\n", saddr.sa_data);
+ continue;
+ }
+ netdev_warn(ndev, "NCSI: Set MAC address to %pM\n", saddr.sa_data);
+ break;
+ }
+
+ ndp->gma_flag = ret == 0;
+ return ret;
+}
+
static struct ncsi_rsp_handler {
unsigned char type;
int payload;
@@ -1176,7 +1218,8 @@ static struct ncsi_rsp_handler {
{ NCSI_PKT_RSP_PLDM, -1, ncsi_rsp_handler_pldm },
{ NCSI_PKT_RSP_GPUUID, 20, ncsi_rsp_handler_gpuuid },
{ NCSI_PKT_RSP_QPNPR, -1, ncsi_rsp_handler_pldm },
- { NCSI_PKT_RSP_SNPR, -1, ncsi_rsp_handler_pldm }
+ { NCSI_PKT_RSP_SNPR, -1, ncsi_rsp_handler_pldm },
+ { NCSI_PKT_RSP_GMCMA, -1, ncsi_rsp_handler_gmcma },
};

int ncsi_rcv_rsp(struct sk_buff *skb, struct net_device *dev,
--
2.30.2