[net-next v2 11/14] octeontx2-pf: cn10k: Get max mtu supported from admin function

From: Geetha sowjanya
Date: Tue Feb 02 2021 - 01:04:35 EST


From: Hariprasad Kelam <hkelam@xxxxxxxxxxx>

CN10K supports max MTU of 16K on LMAC links and 64k on LBK
links and Octeontx2 silicon supports 9K mtu on both links.
Get the same from nix_get_hw_info mbox message in netdev probe.

This patch also calculates receive buffer size required based
on the MTU set.

Signed-off-by: Hariprasad Kelam <hkelam@xxxxxxxxxxx>
Signed-off-by: Subbaraya Sundeep <sbhatta@xxxxxxxxxxx>
Signed-off-by: Geetha sowjanya <gakula@xxxxxxxxxxx>
Signed-off-by: Sunil Goutham <sgoutham@xxxxxxxxxxx>
---
drivers/net/ethernet/marvell/octeontx2/nic/cn10k.c | 2 +-
.../ethernet/marvell/octeontx2/nic/otx2_common.c | 43 +++++++++++++++++++++-
.../ethernet/marvell/octeontx2/nic/otx2_common.h | 2 +-
.../net/ethernet/marvell/octeontx2/nic/otx2_pf.c | 33 +++++++++++++++--
.../net/ethernet/marvell/octeontx2/nic/otx2_txrx.c | 27 ++++++++++----
.../net/ethernet/marvell/octeontx2/nic/otx2_txrx.h | 1 -
.../net/ethernet/marvell/octeontx2/nic/otx2_vf.c | 2 +-
7 files changed, 93 insertions(+), 17 deletions(-)

diff --git a/drivers/net/ethernet/marvell/octeontx2/nic/cn10k.c b/drivers/net/ethernet/marvell/octeontx2/nic/cn10k.c
index 1c7d478..238238b 100644
--- a/drivers/net/ethernet/marvell/octeontx2/nic/cn10k.c
+++ b/drivers/net/ethernet/marvell/octeontx2/nic/cn10k.c
@@ -108,7 +108,7 @@ int cn10k_sq_aq_init(void *dev, u16 qidx, u16 sqb_aura)
/* Only one SMQ is allocated, map all SQ's to that SMQ */
aq->sq.smq = pfvf->hw.txschq_list[NIX_TXSCH_LVL_SMQ][0];
/* FIXME: set based on NIX_AF_DWRR_RPM_MTU*/
- aq->sq.smq_rr_weight = OTX2_MAX_MTU;
+ aq->sq.smq_rr_weight = pfvf->netdev->mtu;
aq->sq.default_chan = pfvf->hw.tx_chan_base;
aq->sq.sqe_stype = NIX_STYPE_STF; /* Cache SQB */
aq->sq.sqb_aura = sqb_aura;
diff --git a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.c b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.c
index 2accdc7..f5b3074 100644
--- a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.c
+++ b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.c
@@ -217,7 +217,6 @@ int otx2_hw_set_mtu(struct otx2_nic *pfvf, int mtu)
return -ENOMEM;
}

- pfvf->max_frs = mtu + OTX2_ETH_HLEN;
req->maxlen = pfvf->max_frs;

err = otx2_sync_mbox_msg(&pfvf->mbox);
@@ -591,7 +590,7 @@ int otx2_txschq_config(struct otx2_nic *pfvf, int lvl)
/* Set topology e.t.c configuration */
if (lvl == NIX_TXSCH_LVL_SMQ) {
req->reg[0] = NIX_AF_SMQX_CFG(schq);
- req->regval[0] = ((OTX2_MAX_MTU + OTX2_ETH_HLEN) << 8) |
+ req->regval[0] = ((pfvf->netdev->max_mtu + OTX2_ETH_HLEN) << 8) |
OTX2_MIN_MTU;

req->regval[0] |= (0x20ULL << 51) | (0x80ULL << 39) |
@@ -1618,6 +1617,46 @@ void otx2_set_cints_affinity(struct otx2_nic *pfvf)
}
}

+u16 otx2_get_max_mtu(struct otx2_nic *pfvf)
+{
+ struct nix_hw_info *rsp;
+ struct msg_req *req;
+ u16 max_mtu;
+ int rc;
+
+ mutex_lock(&pfvf->mbox.lock);
+
+ req = otx2_mbox_alloc_msg_nix_get_hw_info(&pfvf->mbox);
+ if (!req) {
+ rc = -ENOMEM;
+ goto out;
+ }
+
+ rc = otx2_sync_mbox_msg(&pfvf->mbox);
+ if (!rc) {
+ rsp = (struct nix_hw_info *)
+ otx2_mbox_get_rsp(&pfvf->mbox.mbox, 0, &req->hdr);
+
+ /* HW counts VLAN insertion bytes (8 for double tag)
+ * irrespective of whether SQE is requesting to insert VLAN
+ * in the packet or not. Hence these 8 bytes have to be
+ * discounted from max packet size otherwise HW will throw
+ * SMQ errors
+ */
+ max_mtu = rsp->max_mtu - 8 - OTX2_ETH_HLEN;
+ }
+
+out:
+ mutex_unlock(&pfvf->mbox.lock);
+ if (rc) {
+ dev_warn(pfvf->dev,
+ "Failed to get MTU from hardware setting default value(1500)\n");
+ max_mtu = 1500;
+ }
+ return max_mtu;
+}
+EXPORT_SYMBOL(otx2_get_max_mtu);
+
#define M(_name, _id, _fn_name, _req_type, _rsp_type) \
int __weak \
otx2_mbox_up_handler_ ## _fn_name(struct otx2_nic *pfvf, \
diff --git a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.h b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.h
index b6bdc6f..1cc7772 100644
--- a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.h
+++ b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.h
@@ -790,5 +790,5 @@ int otx2_del_macfilter(struct net_device *netdev, const u8 *mac);
int otx2_add_macfilter(struct net_device *netdev, const u8 *mac);
int otx2_enable_rxvlan(struct otx2_nic *pf, bool enable);
int otx2_install_rxvlan_offload_flow(struct otx2_nic *pfvf);
-
+u16 otx2_get_max_mtu(struct otx2_nic *pfvf);
#endif /* OTX2_COMMON_H */
diff --git a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_pf.c b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_pf.c
index 7cb24df..05e782f 100644
--- a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_pf.c
+++ b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_pf.c
@@ -1285,6 +1285,33 @@ static void otx2_free_sq_res(struct otx2_nic *pf)
}
}

+static int otx2_get_rbuf_size(struct otx2_nic *pf, int mtu)
+{
+ int frame_size;
+ int total_size;
+ int rbuf_size;
+
+ /* The data transferred by NIX to memory consists of actual packet
+ * plus additional data which has timestamp and/or EDSA/HIGIG2
+ * headers if interface is configured in corresponding modes.
+ * NIX transfers entire data using 6 segments/buffers and writes
+ * a CQE_RX descriptor with those segment addresses. First segment
+ * has additional data prepended to packet. Also software omits a
+ * headroom of 128 bytes and sizeof(struct skb_shared_info) in
+ * each segment. Hence the total size of memory needed
+ * to receive a packet with 'mtu' is:
+ * frame size = mtu + additional data;
+ * memory = frame_size + (headroom + struct skb_shared_info size) * 6;
+ * each receive buffer size = memory / 6;
+ */
+ frame_size = mtu + OTX2_ETH_HLEN + OTX2_HW_TIMESTAMP_LEN;
+ total_size = frame_size + (OTX2_HEAD_ROOM +
+ OTX2_DATA_ALIGN(sizeof(struct skb_shared_info))) * 6;
+ rbuf_size = total_size / 6;
+
+ return ALIGN(rbuf_size, 2048);
+}
+
static int otx2_init_hw_resources(struct otx2_nic *pf)
{
struct nix_lf_free_req *free_req;
@@ -1301,9 +1328,7 @@ static int otx2_init_hw_resources(struct otx2_nic *pf)
hw->sqpool_cnt = hw->tx_queues;
hw->pool_cnt = hw->rqpool_cnt + hw->sqpool_cnt;

- /* Get the size of receive buffers to allocate */
- pf->rbsize = RCV_FRAG_LEN(OTX2_HW_TIMESTAMP_LEN + pf->netdev->mtu +
- OTX2_ETH_HLEN);
+ pf->rbsize = otx2_get_rbuf_size(pf, pf->netdev->mtu);

mutex_lock(&mbox->lock);
/* NPA init */
@@ -2426,7 +2451,7 @@ static int otx2_probe(struct pci_dev *pdev, const struct pci_device_id *id)

/* MTU range: 64 - 9190 */
netdev->min_mtu = OTX2_MIN_MTU;
- netdev->max_mtu = OTX2_MAX_MTU;
+ netdev->max_mtu = otx2_get_max_mtu(pf);

err = register_netdev(netdev);
if (err) {
diff --git a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_txrx.c b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_txrx.c
index cdae83c..00e9e65 100644
--- a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_txrx.c
+++ b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_txrx.c
@@ -256,12 +256,11 @@ static bool otx2_check_rcv_errors(struct otx2_nic *pfvf,
/* For now ignore all the NPC parser errors and
* pass the packets to stack.
*/
- if (cqe->sg.segs == 1)
- return false;
+ return false;
}

/* If RXALL is enabled pass on packets to stack. */
- if (cqe->sg.segs == 1 && (pfvf->netdev->features & NETIF_F_RXALL))
+ if (pfvf->netdev->features & NETIF_F_RXALL)
return false;

/* Free buffer back to pool */
@@ -276,9 +275,14 @@ static void otx2_rcv_pkt_handler(struct otx2_nic *pfvf,
struct nix_cqe_rx_s *cqe)
{
struct nix_rx_parse_s *parse = &cqe->parse;
+ struct nix_rx_sg_s *sg = &cqe->sg;
struct sk_buff *skb = NULL;
+ void *end, *start;
+ u64 *seg_addr;
+ u16 *seg_size;
+ int seg;

- if (unlikely(parse->errlev || parse->errcode || cqe->sg.segs > 1)) {
+ if (unlikely(parse->errlev || parse->errcode)) {
if (otx2_check_rcv_errors(pfvf, cqe, cq->cq_idx))
return;
}
@@ -287,9 +291,18 @@ static void otx2_rcv_pkt_handler(struct otx2_nic *pfvf,
if (unlikely(!skb))
return;

- otx2_skb_add_frag(pfvf, skb, cqe->sg.seg_addr, cqe->sg.seg_size, parse);
- cq->pool_ptrs++;
-
+ start = (void *)sg;
+ end = start + ((cqe->parse.desc_sizem1 + 1) * 16);
+ while (start < end) {
+ sg = (struct nix_rx_sg_s *)start;
+ seg_addr = &sg->seg_addr;
+ seg_size = (void *)sg;
+ for (seg = 0; seg < sg->segs; seg++, seg_addr++) {
+ otx2_skb_add_frag(pfvf, skb, *seg_addr, seg_size[seg], parse);
+ cq->pool_ptrs++;
+ }
+ start += sizeof(*sg);
+ }
otx2_set_rxhash(pfvf, cqe, skb);

skb_record_rx_queue(skb, cq->cq_idx);
diff --git a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_txrx.h b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_txrx.h
index d2b26b3..52486c1 100644
--- a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_txrx.h
+++ b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_txrx.h
@@ -24,7 +24,6 @@

#define OTX2_ETH_HLEN (VLAN_ETH_HLEN + VLAN_HLEN)
#define OTX2_MIN_MTU 64
-#define OTX2_MAX_MTU (9212 - OTX2_ETH_HLEN)

#define OTX2_MAX_GSO_SEGS 255
#define OTX2_MAX_FRAGS_IN_SQE 9
diff --git a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_vf.c b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_vf.c
index 31e0325..085be90 100644
--- a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_vf.c
+++ b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_vf.c
@@ -586,7 +586,7 @@ static int otx2vf_probe(struct pci_dev *pdev, const struct pci_device_id *id)

/* MTU range: 68 - 9190 */
netdev->min_mtu = OTX2_MIN_MTU;
- netdev->max_mtu = OTX2_MAX_MTU;
+ netdev->max_mtu = otx2_get_max_mtu(vf);

INIT_WORK(&vf->reset_task, otx2vf_reset_task);

--
2.7.4