net: lan966x: Add offload support for cbs

Lan966x switch supports credit based shaper in hardware according to
IEEE Std 802.1Q-2018 Section 8.6.8.2. Add support for cbs configuration
on egress port of lan966x switch.

Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/microchip/lan966x/Makefile b/drivers/net/ethernet/microchip/lan966x/Makefile
index a3a519d..bc76949 100644 (file)
--- a/drivers/net/ethernet/microchip/lan966x/Makefile
+++ b/drivers/net/ethernet/microchip/lan966x/Makefile
@@ -10,4 +10,4 @@ lan966x-switch-objs  := lan966x_main.o lan966x_phylink.o lan966x_port.o \
                        lan966x_vlan.o lan966x_fdb.o lan966x_mdb.o \
                        lan966x_ptp.o lan966x_fdma.o lan966x_lag.o \
                        lan966x_tc.o lan966x_mqprio.o lan966x_taprio.o \
-                       lan966x_tbf.o
+                       lan966x_tbf.o lan966x_cbs.o

diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_cbs.c b/drivers/net/ethernet/microchip/lan966x/lan966x_cbs.c
new file mode 100644 (file)
index 0000000..70cbbf8
--- /dev/null
+++ b/drivers/net/ethernet/microchip/lan966x/lan966x_cbs.c
@@ -0,0 +1,70 @@
+// SPDX-License-Identifier: GPL-2.0+
+
+#include "lan966x_main.h"
+
+int lan966x_cbs_add(struct lan966x_port *port,
+                   struct tc_cbs_qopt_offload *qopt)
+{
+       struct lan966x *lan966x = port->lan966x;
+       u32 cir, cbs;
+       u8 se_idx;
+
+       /* Check for invalid values */
+       if (qopt->idleslope <= 0 ||
+           qopt->sendslope >= 0 ||
+           qopt->locredit >= qopt->hicredit)
+               return -EINVAL;
+
+       se_idx = SE_IDX_QUEUE + port->chip_port * NUM_PRIO_QUEUES + qopt->queue;
+       cir = qopt->idleslope;
+       cbs = (qopt->idleslope - qopt->sendslope) *
+               (qopt->hicredit - qopt->locredit) /
+               -qopt->sendslope;
+
+       /* Rate unit is 100 kbps */
+       cir = DIV_ROUND_UP(cir, 100);
+       /* Avoid using zero rate */
+       cir = cir ?: 1;
+       /* Burst unit is 4kB */
+       cbs = DIV_ROUND_UP(cbs, 4096);
+       /* Avoid using zero burst */
+       cbs = cbs ?: 1;
+
+       /* Check that actually the result can be written */
+       if (cir > GENMASK(15, 0) ||
+           cbs > GENMASK(6, 0))
+               return -EINVAL;
+
+       lan_rmw(QSYS_SE_CFG_SE_AVB_ENA_SET(1) |
+               QSYS_SE_CFG_SE_FRM_MODE_SET(1),
+               QSYS_SE_CFG_SE_AVB_ENA |
+               QSYS_SE_CFG_SE_FRM_MODE,
+               lan966x, QSYS_SE_CFG(se_idx));
+
+       lan_wr(QSYS_CIR_CFG_CIR_RATE_SET(cir) |
+              QSYS_CIR_CFG_CIR_BURST_SET(cbs),
+              lan966x, QSYS_CIR_CFG(se_idx));
+
+       return 0;
+}
+
+int lan966x_cbs_del(struct lan966x_port *port,
+                   struct tc_cbs_qopt_offload *qopt)
+{
+       struct lan966x *lan966x = port->lan966x;
+       u8 se_idx;
+
+       se_idx = SE_IDX_QUEUE + port->chip_port * NUM_PRIO_QUEUES + qopt->queue;
+
+       lan_rmw(QSYS_SE_CFG_SE_AVB_ENA_SET(1) |
+               QSYS_SE_CFG_SE_FRM_MODE_SET(0),
+               QSYS_SE_CFG_SE_AVB_ENA |
+               QSYS_SE_CFG_SE_FRM_MODE,
+               lan966x, QSYS_SE_CFG(se_idx));
+
+       lan_wr(QSYS_CIR_CFG_CIR_RATE_SET(0) |
+              QSYS_CIR_CFG_CIR_BURST_SET(0),
+              lan966x, QSYS_CIR_CFG(se_idx));
+
+       return 0;
+}

diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_main.h b/drivers/net/ethernet/microchip/lan966x/lan966x_main.h
index 59f5a6b..168456f 100644 (file)
--- a/drivers/net/ethernet/microchip/lan966x/lan966x_main.h
+++ b/drivers/net/ethernet/microchip/lan966x/lan966x_main.h
@@ -471,6 +471,11 @@ int lan966x_tbf_add(struct lan966x_port *port,
 int lan966x_tbf_del(struct lan966x_port *port,
                    struct tc_tbf_qopt_offload *qopt);
 
+int lan966x_cbs_add(struct lan966x_port *port,
+                   struct tc_cbs_qopt_offload *qopt);
+int lan966x_cbs_del(struct lan966x_port *port,
+                   struct tc_cbs_qopt_offload *qopt);
+
 static inline void __iomem *lan_addr(void __iomem *base[],
                                     int id, int tinst, int tcnt,
                                     int gbase, int ginst,

diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_tc.c b/drivers/net/ethernet/microchip/lan966x/lan966x_tc.c
index ca03b78..4b05535 100644 (file)
--- a/drivers/net/ethernet/microchip/lan966x/lan966x_tc.c
+++ b/drivers/net/ethernet/microchip/lan966x/lan966x_tc.c
@@ -37,6 +37,13 @@ static int lan966x_tc_setup_qdisc_tbf(struct lan966x_port *port,
        return -EOPNOTSUPP;
 }
 
+static int lan966x_tc_setup_qdisc_cbs(struct lan966x_port *port,
+                                     struct tc_cbs_qopt_offload *qopt)
+{
+       return qopt->enable ? lan966x_cbs_add(port, qopt) :
+                             lan966x_cbs_del(port, qopt);
+}
+
 int lan966x_tc_setup(struct net_device *dev, enum tc_setup_type type,
                     void *type_data)
 {
@@ -49,6 +56,8 @@ int lan966x_tc_setup(struct net_device *dev, enum tc_setup_type type,
                return lan966x_tc_setup_qdisc_taprio(port, type_data);
        case TC_SETUP_QDISC_TBF:
                return lan966x_tc_setup_qdisc_tbf(port, type_data);
+       case TC_SETUP_QDISC_CBS:
+               return lan966x_tc_setup_qdisc_cbs(port, type_data);
        default:
                return -EOPNOTSUPP;
        }