Subject: Re: [v1,net-next, 2/2] enetc: implement the enetc 802.1Qbu hardware function

From: Ivan Khoronzhuk <[email-masked]>
Date: Wed, 4 Dec 2019 03:35:12 +0200

On Wed, Nov 27, 2019 at 09:59:30AM +0000, Po Liu wrote:

Hi, Po Liu

>The interface follow up the ethtool 'preemption' set/get.
>Hardware features also need to set hw_features with
>NETIF_F_PREEMPTION flag. So ethtool could check kernel
>link features if there is preemption capability of port.
>
>There are two MACs in ENETC. One is express MAC which traffic
>classes in it are advanced transmition. Another is preemptable
>MAC which traffic classes are frame preemptable.
>
>The hardware need to initialize the MACs at initial stage.
>And then set the preemption enable registers of traffic
>classes when ethtool set .get_link_ksettings/.set_link_ksettings
>stage.
>
>To test the ENETC preemption capability, user need to set mqprio
>or taprio to mapping the traffic classes with priorities. Then
>use ethtool command to set 'preemption' with a 8 bits value.
>MSB represent high number traffic class.
>
>Signed-off-by: Po Liu <[email-masked]>
>---
> drivers/net/ethernet/freescale/enetc/enetc.c  |   3 +
> drivers/net/ethernet/freescale/enetc/enetc.h  |   4 +
> .../ethernet/freescale/enetc/enetc_ethtool.c  | 142 ++++++++++++++++--
> .../net/ethernet/freescale/enetc/enetc_hw.h   |  17 +++
> .../net/ethernet/freescale/enetc/enetc_pf.c   |  15 +-
> .../net/ethernet/freescale/enetc/enetc_qos.c  |   4 +

[...]

>+
>+static u32 enetc_preemption_get(struct net_device *ndev)
>+{
>+	struct enetc_ndev_priv *priv = netdev_priv(ndev);
>+	u32 ptvector = 0;
>+	u8 tc_num;
>+	int i;
>+
>+	/* If preemptable MAC is not enable return 0 */
>+	if (!(enetc_port_rd(&priv->si->hw, ENETC_PFPMR) & ENETC_PFPMR_PMACE))
>+		return 0;
>+
>+	tc_num = enetc_get_tc_num(priv->si);
>+
>+	for (i = 0; i < tc_num; i++)
>+		if (enetc_port_rd(&priv->si->hw, ENETC_PTCFPR(i)) & ENETC_FPE)
>+			ptvector |= 1 << i;

Would be better to replace above on just priv var?

>+
>+	return ptvector;
>+}
>+
>+static int enetc_get_link_ksettings(struct net_device *ndev,
>+				    struct ethtool_link_ksettings *cmd)
>+{
>+	cmd->base.preemption = enetc_preemption_get(ndev);
>+
>+	return phy_ethtool_get_link_ksettings(ndev, cmd);
>+}
>+
>+static int enetc_set_link_ksettings(struct net_device *ndev,
>+				    const struct ethtool_link_ksettings *cmd)
>+{
>+	int err;
>+
>+	err = enetc_preemption_set(ndev, cmd->base.preemption);
>+	if (err)
>+		return err;

Shouldn't it be after
phy_ethtool_set_link_ksettings() ?

I mean after potential phy restart, does it have impact on it?

>+
>+	return phy_ethtool_set_link_ksettings(ndev, cmd);
>+}
>+
> static const struct ethtool_ops enetc_pf_ethtool_ops = {
> 	.get_regs_len = enetc_get_reglen,
> 	.get_regs = enetc_get_regs,
>@@ -622,8 +746,8 @@ static const struct ethtool_ops enetc_pf_ethtool_ops = {
> 	.get_rxfh = enetc_get_rxfh,
> 	.set_rxfh = enetc_set_rxfh,
> 	.get_ringparam = enetc_get_ringparam,
>-	.get_link_ksettings = phy_ethtool_get_link_ksettings,
>-	.set_link_ksettings = phy_ethtool_set_link_ksettings,
>+	.get_link_ksettings = enetc_get_link_ksettings,
>+	.set_link_ksettings = enetc_set_link_ksettings,
> 	.get_link = ethtool_op_get_link,
> 	.get_ts_info = enetc_get_ts_info,
> 	.get_wol = enetc_get_wol,
>diff --git a/drivers/net/ethernet/freescale/enetc/enetc_hw.h b/drivers/net/ethernet/freescale/enetc/enetc_hw.h
>index 51f543ef37a8..b609ec095710 100644
>--- a/drivers/net/ethernet/freescale/enetc/enetc_hw.h
>+++ b/drivers/net/ethernet/freescale/enetc/enetc_hw.h
>@@ -19,6 +19,7 @@
> #define ENETC_SICTR1	0x1c
> #define ENETC_SIPCAPR0	0x20
> #define ENETC_SIPCAPR0_QBV	BIT(4)
>+#define ENETC_SIPCAPR0_QBU	BIT(3)
> #define ENETC_SIPCAPR0_RSS	BIT(8)
> #define ENETC_SIPCAPR1	0x24
> #define ENETC_SITGTGR	0x30
>@@ -176,6 +177,7 @@ enum enetc_bdr_type {TX, RX};
> #define ENETC_PCAPR0_RXBDR(val)	((val) >> 24)
> #define ENETC_PCAPR0_TXBDR(val)	(((val) >> 16) & 0xff)
> #define ENETC_PCAPR1		0x0904
>+#define ENETC_NUM_TCS_MASK	GENMASK(6, 4)
> #define ENETC_PSICFGR0(n)	(0x0940 + (n) * 0xc)  /* n = SI index */
> #define ENETC_PSICFGR0_SET_TXBDR(val)	((val) & 0xff)
> #define ENETC_PSICFGR0_SET_RXBDR(val)	(((val) & 0xff) << 16)
>@@ -223,6 +225,7 @@ enum enetc_bdr_type {TX, RX};
> #define ENETC_SET_TX_MTU(val)	((val) << 16)
> #define ENETC_SET_MAXFRM(val)	((val) & 0xffff)
> #define ENETC_PM0_IF_MODE	0x8300
>+#define ENETC_PM1_IF_MODE       0x9300
> #define ENETC_PMO_IFM_RG	BIT(2)
> #define ENETC_PM0_IFM_RLP	(BIT(5) | BIT(11))
> #define ENETC_PM0_IFM_RGAUTO	(BIT(15) | ENETC_PMO_IFM_RG | BIT(1))
>@@ -276,6 +279,15 @@ enum enetc_bdr_type {TX, RX};
> #define ENETC_PM0_TSCOL		0x82E0
> #define ENETC_PM0_TLCOL		0x82E8
> #define ENETC_PM0_TECOL		0x82F0
>+#define ENETC_PM1_RFRM		0x9120
>+#define ENETC_PM1_RDRP		0x9158
>+#define ENETC_PM1_RPKT		0x9160
>+#define ENETC_PM1_RFRG		0x91B8
>+#define ENETC_PM1_TFRM		0x9220
>+#define ENETC_PM1_TERR		0x9238
>+#define ENETC_PM1_TPKT		0x9260
>+#define ENETC_MAC_MERGE_MMFCRXR	0x1f14
>+#define ENETC_MAC_MERGE_MMFCTXR	0x1f18
>
> /* Port counters */
> #define ENETC_PICDR(n)		(0x0700 + (n) * 8) /* n = [0..3] */
>@@ -615,3 +627,8 @@ struct enetc_cbd {
> /* Port time gating capability register */
> #define ENETC_QBV_PTGCAPR_OFFSET	0x11a08
> #define ENETC_QBV_MAX_GCL_LEN_MASK	GENMASK(15, 0)
>+
>+#define ENETC_QBU_TC_MASK	GENMASK(7, 0)
>+
>+#define ENETC_PTCFPR(n)         (0x1910 + (n) * 4)
>+#define ENETC_FPE               BIT(31)
>diff --git a/drivers/net/ethernet/freescale/enetc/enetc_pf.c b/drivers/net/ethernet/freescale/enetc/enetc_pf.c
>index e7482d483b28..f1873c4da77f 100644
>--- a/drivers/net/ethernet/freescale/enetc/enetc_pf.c
>+++ b/drivers/net/ethernet/freescale/enetc/enetc_pf.c
>@@ -523,10 +523,15 @@ static void enetc_configure_port_mac(struct enetc_hw *hw)
> 		      ENETC_PM0_CMD_TXP	| ENETC_PM0_PROMISC |
> 		      ENETC_PM0_TX_EN | ENETC_PM0_RX_EN);
> 	/* set auto-speed for RGMII */
>-	if (enetc_port_rd(hw, ENETC_PM0_IF_MODE) & ENETC_PMO_IFM_RG)
>+	if (enetc_port_rd(hw, ENETC_PM0_IF_MODE) & ENETC_PMO_IFM_RG) {
> 		enetc_port_wr(hw, ENETC_PM0_IF_MODE, ENETC_PM0_IFM_RGAUTO);
>-	if (enetc_global_rd(hw, ENETC_G_EPFBLPR(1)) == ENETC_G_EPFBLPR1_XGMII)
>+		enetc_port_wr(hw, ENETC_PM1_IF_MODE, ENETC_PM0_IFM_RGAUTO);
>+	}
>+
>+	if (enetc_global_rd(hw, ENETC_G_EPFBLPR(1)) == ENETC_G_EPFBLPR1_XGMII) {
> 		enetc_port_wr(hw, ENETC_PM0_IF_MODE, ENETC_PM0_IFM_XGMII);
>+		enetc_port_wr(hw, ENETC_PM1_IF_MODE, ENETC_PM0_IFM_XGMII);
>+	}
> }
>
> static void enetc_configure_port_pmac(struct enetc_hw *hw)
>@@ -745,6 +750,12 @@ static void enetc_pf_netdev_setup(struct enetc_si *si, struct net_device *ndev,
> 	if (si->hw_features & ENETC_SI_F_QBV)
> 		priv->active_offloads |= ENETC_F_QBV;
>
>+	if (si->hw_features & ENETC_SI_F_QBU) {
>+		ndev->hw_features |= NETIF_F_PREEMPTION;
>+		ndev->features |= NETIF_F_PREEMPTION;
>+		priv->active_offloads |= ENETC_F_QBU;
>+	}
>+
> 	/* pick up primary MAC address from SI */
> 	enetc_get_primary_mac_addr(&si->hw, ndev->dev_addr);
> }
>diff --git a/drivers/net/ethernet/freescale/enetc/enetc_qos.c b/drivers/net/ethernet/freescale/enetc/enetc_qos.c
>index 2e99438cb1bf..94dde847d052 100644
>--- a/drivers/net/ethernet/freescale/enetc/enetc_qos.c
>+++ b/drivers/net/ethernet/freescale/enetc/enetc_qos.c
>@@ -169,6 +169,10 @@ int enetc_setup_tc_taprio(struct net_device *ndev, void *type_data)
> 					   priv->tx_ring[i]->index,
> 					   taprio->enable ? 0 : i);
>
>+	/* preemption off if TC priority is all 0 */
>+	if ((err && taprio->enable) || !(err || taprio->enable))
>+		enetc_preemption_set(ndev, 0);
>+
> 	return err;
> }
>
>-- 
>2.17.1
>

-- 
Regards,
Ivan Khoronzhuk