From 3426e5e4339f124f00eef8815b56a80481364550 Mon Sep 17 00:00:00 2001 From: Po Liu Date: Mon, 25 Nov 2019 05:56:56 +0000 Subject: [PATCH] enetc: add support Credit Based Shaper(CBS) for hardware offload The ENETC hardware support the Credit Based Shaper(CBS) which part of the IEEE-802.1Qav. The CBS driver was loaded by the sch_cbs interface when set in the QOS in the kernel. Here is an example command to set 20Mbits bandwidth in 1Gbits port for taffic class 7: tc qdisc add dev eth0 root handle 1: mqprio \ num_tc 8 map 0 1 2 3 4 5 6 7 hw 1 tc qdisc replace dev eth0 parent 1:8 cbs \ locredit -1470 hicredit 30 \ sendslope -980000 idleslope 20000 offload 1 Signed-off-by: Po Liu Reviewed-by: Claudiu Manoil Reviewed-by: Vladimir Oltean Signed-off-by: David S. Miller --- drivers/net/ethernet/freescale/enetc/Kconfig | 4 +- drivers/net/ethernet/freescale/enetc/enetc.c | 2 + drivers/net/ethernet/freescale/enetc/enetc.h | 2 + drivers/net/ethernet/freescale/enetc/enetc_hw.h | 4 + drivers/net/ethernet/freescale/enetc/enetc_qos.c | 128 +++++++++++++++++++++++ 5 files changed, 138 insertions(+), 2 deletions(-) --- a/drivers/net/ethernet/freescale/enetc/Kconfig +++ b/drivers/net/ethernet/freescale/enetc/Kconfig @@ -53,10 +53,10 @@ config FSL_ENETC_HW_TIMESTAMPING config FSL_ENETC_QOS bool "ENETC hardware Time-sensitive Network support" - depends on (FSL_ENETC || FSL_ENETC_VF) && NET_SCH_TAPRIO + depends on (FSL_ENETC || FSL_ENETC_VF) && (NET_SCH_TAPRIO || NET_SCH_CBS) help There are Time-Sensitive Network(TSN) capabilities(802.1Qbv/802.1Qci /802.1Qbu etc.) supported by ENETC. These TSN capabilities can be set enable/disable from user space via Qos commands(tc). In the kernel side, it can be loaded by Qos driver. Currently, it is only support - taprio(802.1Qbv). + taprio(802.1Qbv) and Credit Based Shaper(802.1Qbu). --- a/drivers/net/ethernet/freescale/enetc/enetc.c +++ b/drivers/net/ethernet/freescale/enetc/enetc.c @@ -1521,6 +1521,8 @@ int enetc_setup_tc(struct net_device *nd return enetc_setup_tc_mqprio(ndev, type_data); case TC_SETUP_QDISC_TAPRIO: return enetc_setup_tc_taprio(ndev, type_data); + case TC_SETUP_QDISC_CBS: + return enetc_setup_tc_cbs(ndev, type_data); default: return -EOPNOTSUPP; } --- a/drivers/net/ethernet/freescale/enetc/enetc.h +++ b/drivers/net/ethernet/freescale/enetc/enetc.h @@ -260,7 +260,9 @@ int enetc_send_cmd(struct enetc_si *si, #ifdef CONFIG_FSL_ENETC_QOS int enetc_setup_tc_taprio(struct net_device *ndev, void *type_data); void enetc_sched_speed_set(struct net_device *ndev); +int enetc_setup_tc_cbs(struct net_device *ndev, void *type_data); #else #define enetc_setup_tc_taprio(ndev, type_data) -EOPNOTSUPP #define enetc_sched_speed_set(ndev) (void)0 +#define enetc_setup_tc_cbs(ndev, type_data) -EOPNOTSUPP #endif --- a/drivers/net/ethernet/freescale/enetc/enetc_hw.h +++ b/drivers/net/ethernet/freescale/enetc/enetc_hw.h @@ -185,6 +185,8 @@ enum enetc_bdr_type {TX, RX}; #define ENETC_PSICFGR0_SIVC(bmp) (((bmp) & 0xff) << 24) /* VLAN_TYPE */ #define ENETC_PTCCBSR0(n) (0x1110 + (n) * 8) /* n = 0 to 7*/ +#define ENETC_CBSE BIT(31) +#define ENETC_CBS_BW_MASK GENMASK(6, 0) #define ENETC_PTCCBSR1(n) (0x1114 + (n) * 8) /* n = 0 to 7*/ #define ENETC_RSSHASH_KEY_SIZE 40 #define ENETC_PRSSCAPR 0x1404 @@ -679,6 +681,8 @@ struct enetc_cbd { u8 status_flags; }; +#define ENETC_CLK 400000000ULL + /* port time gating control register */ #define ENETC_QBV_PTGCR_OFFSET 0x11a00 #define ENETC_QBV_TGE BIT(31) --- a/drivers/net/ethernet/freescale/enetc/enetc_qos.c +++ b/drivers/net/ethernet/freescale/enetc/enetc_qos.c @@ -4,6 +4,7 @@ #include "enetc.h" #include +#include static u16 enetc_get_max_gcl_len(struct enetc_hw *hw) { @@ -170,3 +171,130 @@ int enetc_setup_tc_taprio(struct net_dev return err; } + +static u32 enetc_get_cbs_enable(struct enetc_hw *hw, u8 tc) +{ + return enetc_port_rd(hw, ENETC_PTCCBSR0(tc)) & ENETC_CBSE; +} + +static u8 enetc_get_cbs_bw(struct enetc_hw *hw, u8 tc) +{ + return enetc_port_rd(hw, ENETC_PTCCBSR0(tc)) & ENETC_CBS_BW_MASK; +} + +int enetc_setup_tc_cbs(struct net_device *ndev, void *type_data) +{ + struct enetc_ndev_priv *priv = netdev_priv(ndev); + struct tc_cbs_qopt_offload *cbs = type_data; + u32 port_transmit_rate = priv->speed; + u8 tc_nums = netdev_get_num_tc(ndev); + struct enetc_si *si = priv->si; + u32 hi_credit_bit, hi_credit_reg; + u32 max_interference_size; + u32 port_frame_max_size; + u32 tc_max_sized_frame; + u8 tc = cbs->queue; + u8 prio_top, prio_next; + int bw_sum = 0; + u8 bw; + + prio_top = netdev_get_prio_tc_map(ndev, tc_nums - 1); + prio_next = netdev_get_prio_tc_map(ndev, tc_nums - 2); + + /* Support highest prio and second prio tc in cbs mode */ + if (tc != prio_top && tc != prio_next) + return -EOPNOTSUPP; + + if (!cbs->enable) { + /* Make sure the other TC that are numerically + * lower than this TC have been disabled. + */ + if (tc == prio_top && + enetc_get_cbs_enable(&si->hw, prio_next)) { + dev_err(&ndev->dev, + "Disable TC%d before disable TC%d\n", + prio_next, tc); + return -EINVAL; + } + + enetc_port_wr(&si->hw, ENETC_PTCCBSR1(tc), 0); + enetc_port_wr(&si->hw, ENETC_PTCCBSR0(tc), 0); + + return 0; + } + + if (cbs->idleslope - cbs->sendslope != port_transmit_rate * 1000L || + cbs->idleslope < 0 || cbs->sendslope > 0) + return -EOPNOTSUPP; + + port_frame_max_size = ndev->mtu + VLAN_ETH_HLEN + ETH_FCS_LEN; + + bw = cbs->idleslope / (port_transmit_rate * 10UL); + + /* Make sure the other TC that are numerically + * higher than this TC have been enabled. + */ + if (tc == prio_next) { + if (!enetc_get_cbs_enable(&si->hw, prio_top)) { + dev_err(&ndev->dev, + "Enable TC%d first before enable TC%d\n", + prio_top, prio_next); + return -EINVAL; + } + bw_sum += enetc_get_cbs_bw(&si->hw, prio_top); + } + + if (bw_sum + bw >= 100) { + dev_err(&ndev->dev, + "The sum of all CBS Bandwidth can't exceed 100\n"); + return -EINVAL; + } + + tc_max_sized_frame = enetc_port_rd(&si->hw, ENETC_PTCMSDUR(tc)); + + /* For top prio TC, the max_interfrence_size is maxSizedFrame. + * + * For next prio TC, the max_interfrence_size is calculated as below: + * + * max_interference_size = M0 + Ma + Ra * M0 / (R0 - Ra) + * + * - RA: idleSlope for AVB Class A + * - R0: port transmit rate + * - M0: maximum sized frame for the port + * - MA: maximum sized frame for AVB Class A + */ + + if (tc == prio_top) { + max_interference_size = port_frame_max_size * 8; + } else { + u32 m0, ma, r0, ra; + + m0 = port_frame_max_size * 8; + ma = enetc_port_rd(&si->hw, ENETC_PTCMSDUR(prio_top)) * 8; + ra = enetc_get_cbs_bw(&si->hw, prio_top) * + port_transmit_rate * 10000ULL; + r0 = port_transmit_rate * 1000000ULL; + max_interference_size = m0 + ma + + (u32)div_u64((u64)ra * m0, r0 - ra); + } + + /* hiCredit bits calculate by: + * + * maxSizedFrame * (idleSlope/portTxRate) + */ + hi_credit_bit = max_interference_size * bw / 100; + + /* hiCredit bits to hiCredit register need to calculated as: + * + * (enetClockFrequency / portTransmitRate) * 100 + */ + hi_credit_reg = (u32)div_u64((ENETC_CLK * 100ULL) * hi_credit_bit, + port_transmit_rate * 1000000ULL); + + enetc_port_wr(&si->hw, ENETC_PTCCBSR1(tc), hi_credit_reg); + + /* Set bw register and enable this traffic class */ + enetc_port_wr(&si->hw, ENETC_PTCCBSR0(tc), bw | ENETC_CBSE); + + return 0; +}