octeontx2-af: Skip CGX/RPM probe incase of zero lmac count

In few error cases MAC(CGX/RPM) block is having 0 lmacs.
AF driver uses MAC block with lmac pair to get firmware
data etc. These commands will fail as there is no LMAC
associated with MAC block.

This patch skips the probe of these MAC blocks such that AF driver
uses correct MAC block and LMAC pair for firmware communication and
define new LMAC_AF_ERROR types for command timeout etc.

This patch also enables channel back pressure for all LMACs.
Signed-off-by: Hariprasad Kelam <hkelam@marvell.com>
Signed-off-by: Sunil Kovvuri Goutham <sgoutham@marvell.com>
Signed-off-by: Geetha sowjanya <gakula@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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

@@ -1012,9 +1012,9 @@ int cgx_fwi_cmd_send(u64 req, u64 *resp, struct lmac *lmac)
 	if (!wait_event_timeout(lmac->wq_cmd_cmplt, !lmac->cmd_pend,
 				msecs_to_jiffies(CGX_CMD_TIMEOUT))) {
 		dev = &cgx->pdev->dev;
-		dev_err(dev, "cgx port %d:%d cmd timeout\n",
-			cgx->cgx_id, lmac->lmac_id);
-		err = -EIO;
+		dev_err(dev, "cgx port %d:%d cmd %lld timeout\n",
+			cgx->cgx_id, lmac->lmac_id, FIELD_GET(CMDREG_ID, req));
+		err = LMAC_AF_ERR_CMD_TIMEOUT;
 		goto unlock;
 	}
 
@@ -1750,6 +1750,13 @@ static int cgx_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 		goto err_release_regions;
 	}
 
+	cgx->lmac_count = cgx->mac_ops->get_nr_lmacs(cgx);
+	if (!cgx->lmac_count) {
+		dev_notice(dev, "CGX %d LMAC count is zero, skipping probe\n", cgx->cgx_id);
+		err = -EOPNOTSUPP;
+		goto err_release_regions;
+	}
+
 	nvec = pci_msix_vec_count(cgx->pdev);
 	err = pci_alloc_irq_vectors(pdev, nvec, nvec, PCI_IRQ_MSIX);
 	if (err < 0 || err != nvec) {

drivers/net/ethernet/marvell/octeontx2/af/mbox.h

@@ -1648,6 +1648,8 @@ enum cgx_af_status {
 	LMAC_AF_ERR_PERM_DENIED		= -1103,
 	LMAC_AF_ERR_PFC_ENADIS_PERM_DENIED       = -1104,
 	LMAC_AF_ERR_8023PAUSE_ENADIS_PERM_DENIED = -1105,
+	LMAC_AF_ERR_CMD_TIMEOUT = -1106,
+	LMAC_AF_ERR_FIRMWARE_DATA_NOT_MAPPED = -1107,
 	LMAC_AF_ERR_EXACT_MATCH_TBL_ADD_FAILED = -1108,
 	LMAC_AF_ERR_EXACT_MATCH_TBL_DEL_FAILED = -1109,
 	LMAC_AF_ERR_EXACT_MATCH_TBL_LOOK_UP_FAILED = -1110,

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

@@ -281,6 +281,9 @@ void rpm_lmac_pause_frm_config(void *rpmd, int lmac_id, bool enable)
 	cfg = rpm_read(rpm, lmac_id, RPMX_CMRX_PRT_CBFC_CTL);
 	cfg = FIELD_SET(RPM_PFC_CLASS_MASK, 0, cfg);
 	rpm_write(rpm, lmac_id, RPMX_CMRX_PRT_CBFC_CTL, cfg);
+
+	/* Enable channel mask for all LMACS */
+	rpm_write(rpm, 0, RPMX_CMR_CHAN_MSK_OR, ~0ULL);
 }
 
 int rpm_get_rx_stats(void *rpmd, int lmac_id, int idx, u64 *rx_stat)

drivers/net/ethernet/marvell/octeontx2/af/rpm.h

@@ -51,6 +51,7 @@
 #define RPMX_CMR_RX_OVR_BP		0x4120
 #define RPMX_CMR_RX_OVR_BP_EN(x)	BIT_ULL((x) + 8)
 #define RPMX_CMR_RX_OVR_BP_BP(x)	BIT_ULL((x) + 4)
+#define RPMX_CMR_CHAN_MSK_OR            0x4118
 #define RPMX_MTI_STAT_RX_STAT_PAGES_COUNTERX 0x12000
 #define RPMX_MTI_STAT_TX_STAT_PAGES_COUNTERX 0x13000
 #define RPMX_MTI_STAT_DATA_HI_CDC            0x10038

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

@@ -1087,7 +1087,7 @@ int rvu_mbox_handler_cgx_get_aux_link_info(struct rvu *rvu, struct msg_req *req,
 	u8 cgx_id, lmac_id;
 
 	if (!rvu->fwdata)
-		return -ENXIO;
+		return LMAC_AF_ERR_FIRMWARE_DATA_NOT_MAPPED;
 
 	if (!is_pf_cgxmapped(rvu, pf))
 		return -EPERM;