Re: [PATCH v7 3/3] net/cxgb4: Use new PCI_DEV_FLAGS_NO_RELAXED_ORDERING flag
From: Alexander Duyck
Date: Thu Jul 13 2017 - 14:14:15 EST
On Thu, Jul 13, 2017 at 7:21 AM, Ding Tianhong <dingtianhong@xxxxxxxxxx> wrote:
> From: Casey Leedom <leedom@xxxxxxxxxxx>
>
> cxgb4 Ethernet driver now queries PCIe configuration space to determine
> if it can send TLPs to it with the Relaxed Ordering Attribute set.
>
> Remove the enable_pcie_relaxed_ordering() to avoid enable PCIe Capability
> Device Control[Relaxed Ordering Enable] at probe routine, to make sure
> the driver will not send the Relaxed Ordering TLPs to the Root Complex which
> could not deal the Relaxed Ordering TLPs.
>
> Signed-off-by: Casey Leedom <leedom@xxxxxxxxxxx>
> Signed-off-by: Ding Tianhong <dingtianhong@xxxxxxxxxx>
Ding,
You can probably just drop this patch. If I am understanding Casey
correctly just the fact that the relaxed ordering enable bit is
cleared in the configuration should be enough to do this for the
device automatically.
- Alex
> ---
> drivers/net/ethernet/chelsio/cxgb4/cxgb4.h | 1 +
> drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c | 23 +++++++++++++++++------
> drivers/net/ethernet/chelsio/cxgb4/sge.c | 5 +++--
> 3 files changed, 21 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4.h b/drivers/net/ethernet/chelsio/cxgb4/cxgb4.h
> index ef4be78..09ea62e 100644
> --- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4.h
> +++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4.h
> @@ -529,6 +529,7 @@ enum { /* adapter flags */
> USING_SOFT_PARAMS = (1 << 6),
> MASTER_PF = (1 << 7),
> FW_OFLD_CONN = (1 << 9),
> + ROOT_NO_RELAXED_ORDERING = (1 << 10),
> };
>
> enum {
> diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
> index e403fa1..391e484 100644
> --- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
> +++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
> @@ -4654,11 +4654,6 @@ static void print_port_info(const struct net_device *dev)
> dev->name, adap->params.vpd.id, adap->name, buf);
> }
>
> -static void enable_pcie_relaxed_ordering(struct pci_dev *dev)
> -{
> - pcie_capability_set_word(dev, PCI_EXP_DEVCTL, PCI_EXP_DEVCTL_RELAX_EN);
> -}
> -
> /*
> * Free the following resources:
> * - memory used for tables
> @@ -4908,7 +4903,6 @@ static int init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
> }
>
> pci_enable_pcie_error_reporting(pdev);
> - enable_pcie_relaxed_ordering(pdev);
> pci_set_master(pdev);
> pci_save_state(pdev);
>
> @@ -4947,6 +4941,23 @@ static int init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
> adapter->msg_enable = DFLT_MSG_ENABLE;
> memset(adapter->chan_map, 0xff, sizeof(adapter->chan_map));
>
> + /* If possible, we use PCIe Relaxed Ordering Attribute to deliver
> + * Ingress Packet Data to Free List Buffers in order to allow for
> + * chipset performance optimizations between the Root Complex and
> + * Memory Controllers. (Messages to the associated Ingress Queue
> + * notifying new Packet Placement in the Free Lists Buffers will be
> + * send without the Relaxed Ordering Attribute thus guaranteeing that
> + * all preceding PCIe Transaction Layer Packets will be processed
> + * first.) But some Root Complexes have various issues with Upstream
> + * Transaction Layer Packets with the Relaxed Ordering Attribute set.
> + * The PCIe devices which under the Root Complexes will be cleared the
> + * Relaxed Ordering bit in the configuration space, So we check our
> + * PCIe configuration space to see if it's flagged with advice against
> + * using Relaxed Ordering.
> + */
> + if (!pcie_relaxed_ordering_supported(pdev))
> + adapter->flags |= ROOT_NO_RELAXED_ORDERING;
> +
> spin_lock_init(&adapter->stats_lock);
> spin_lock_init(&adapter->tid_release_lock);
> spin_lock_init(&adapter->win0_lock);
> diff --git a/drivers/net/ethernet/chelsio/cxgb4/sge.c b/drivers/net/ethernet/chelsio/cxgb4/sge.c
> index ede1220..4ef68f6 100644
> --- a/drivers/net/ethernet/chelsio/cxgb4/sge.c
> +++ b/drivers/net/ethernet/chelsio/cxgb4/sge.c
> @@ -2719,6 +2719,7 @@ int t4_sge_alloc_rxq(struct adapter *adap, struct sge_rspq *iq, bool fwevtq,
> struct fw_iq_cmd c;
> struct sge *s = &adap->sge;
> struct port_info *pi = netdev_priv(dev);
> + int relaxed = !(adap->flags & ROOT_NO_RELAXED_ORDERING);
>
> /* Size needs to be multiple of 16, including status entry. */
> iq->size = roundup(iq->size, 16);
> @@ -2772,8 +2773,8 @@ int t4_sge_alloc_rxq(struct adapter *adap, struct sge_rspq *iq, bool fwevtq,
>
> flsz = fl->size / 8 + s->stat_len / sizeof(struct tx_desc);
> c.iqns_to_fl0congen |= htonl(FW_IQ_CMD_FL0PACKEN_F |
> - FW_IQ_CMD_FL0FETCHRO_F |
> - FW_IQ_CMD_FL0DATARO_F |
> + FW_IQ_CMD_FL0FETCHRO_V(relaxed) |
> + FW_IQ_CMD_FL0DATARO_V(relaxed) |
> FW_IQ_CMD_FL0PADEN_F);
> if (cong >= 0)
> c.iqns_to_fl0congen |=
> --
> 1.8.3.1
>
>