[PATCH v2 net] octeontx2-af: fix PF/CGX debugfs PCI bus lookup

[Ratheesh Kannoth <rkannoth@marvell.com>]

rvu_dbg_rvu_pf_cgx_map_display() locates each RVU PF PCI device via
pci_get_domain_bus_and_slot() when printing the PF-to-CGX map. It
assumed PF0 always sits on PCI bus 1 and derived other PF bus numbers
as pf + 1, but the AF device can be enumerated on a different bus.

Use rvu->pdev->bus->number as the base bus instead, so each PF lookup
uses pf + start on systems where RVU functions are on contiguous buses
but do not start at bus 1.

Fixes: e2fb373038654 ("octeontx2-af: Display CGX, NIX and PF map in debugfs.")
Signed-off-by: Subbaraya Sundeep <sbhatta@marvell.com>
Signed-off-by: Ratheesh Kannoth <rkannoth@marvell.com>

---
v1 -> v2: Added fixes tag, and fixed domain number.
	https://lore.kernel.org/netdev/apqE5CT5_M4coO0m@rkannoth-OptiPlex-7090/
---
 .../net/ethernet/marvell/octeontx2/af/rvu_debugfs.c    | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/marvell/octeontx2/af/rvu_debugfs.c b/drivers/net/ethernet/marvell/octeontx2/af/rvu_debugfs.c
index 22ee99676879..904374baae6f 100644
--- a/drivers/net/ethernet/marvell/octeontx2/af/rvu_debugfs.c
+++ b/drivers/net/ethernet/marvell/octeontx2/af/rvu_debugfs.c
@@ -829,19 +829,25 @@ static int rvu_dbg_rvu_pf_cgx_map_display(struct seq_file *filp, void *unused)
 	int pf, domain, blkid;
 	u8 cgx_id, lmac_id;
 	u16 pcifunc;
+	u8 start;
 
-	domain = 2;
+	domain = pci_domain_nr(rvu->pdev->bus);
 	mac_ops = get_mac_ops(rvu_first_cgx_pdata(rvu));
 	/* There can be no CGX devices at all */
 	if (!mac_ops)
 		return 0;
 	seq_printf(filp, "PCI dev\t\tRVU PF Func\tNIX block\t%s\tLMAC\tCHAN\n",
 		   mac_ops->name);
+
+	/* All the PF devices are on contiguous PCI bus numbers, but the PF0(AF)
+	 * may not start from 1 always. Hence get domain and bus from PCI device.
+	 */
+	start = rvu->pdev->bus->number;
 	for (pf = 0; pf < rvu->hw->total_pfs; pf++) {
 		if (!is_pf_cgxmapped(rvu, pf))
 			continue;
 
-		pdev =  pci_get_domain_bus_and_slot(domain, pf + 1, 0);
+		pdev =  pci_get_domain_bus_and_slot(domain, pf + start, 0);
 		if (!pdev)
 			continue;
 
-- 
2.43.0