Octeontx2-af: Add proper checks for fwdata

[ Upstream commit 4a3dba4 ]

firmware populates MAC address, link modes (supported, advertised)
and EEPROM data in shared firmware structure which kernel access
via MAC block(CGX/RPM).

Accessing fwdata, on boards booted with out MAC block leading to
kernel panics.

Internal error: Oops: 0000000096000005 [#1]  SMP
[   10.460721] Modules linked in:
[   10.463779] CPU: 0 UID: 0 PID: 174 Comm: kworker/0:3 Not tainted 6.19.0-rc5-00154-g76ec646abdf7-dirty #3 PREEMPT
[   10.474045] Hardware name: Marvell OcteonTX CN98XX board (DT)
[   10.479793] Workqueue: events work_for_cpu_fn
[   10.484159] pstate: 80400009 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[   10.491124] pc : rvu_sdp_init+0x18/0x114
[   10.495051] lr : rvu_probe+0xe58/0x1d18

Fixes: 9978144 ("Octeontx2-af: Fetch MAC channel info from firmware")
Fixes: 5f21226 ("Octeontx2-pf: ethtool: support multi advertise mode")
Signed-off-by: Hariprasad Kelam <hkelam@marvell.com>
Link: https://patch.msgid.link/20260121094819.2566786-1-hkelam@marvell.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Author: Hariprasad Kelam

drivers/net/ethernet/marvell/octeontx2/af/rvu_cgx.c

@@ -1222,6 +1222,9 @@ int rvu_mbox_handler_cgx_set_link_mode(struct rvu *rvu,
 	u8 cgx_idx, lmac;
 	void *cgxd;
 
+	if (!rvu->fwdata)
+		return LMAC_AF_ERR_FIRMWARE_DATA_NOT_MAPPED;
+
 	if (!is_cgx_config_permitted(rvu, req->hdr.pcifunc))
 		return -EPERM;
 

drivers/net/ethernet/marvell/octeontx2/af/rvu_sdp.c

@@ -56,7 +56,7 @@ int rvu_sdp_init(struct rvu *rvu)
 	struct rvu_pfvf *pfvf;
 	u32 i = 0;
 
-	if (rvu->fwdata->channel_data.valid) {
+	if (rvu->fwdata && rvu->fwdata->channel_data.valid) {
 		sdp_pf_num[0] = 0;
 		pfvf = &rvu->pf[sdp_pf_num[0]];
 		pfvf->sdp_info = &rvu->fwdata->channel_data.info;