From e18058ea99860321851f7e76b8de4a7a4b06f5ed Mon Sep 17 00:00:00 2001 From: Oleksij Rempel Date: Tue, 8 Mar 2022 14:58:57 +0100 Subject: [PATCH] net: dsa: microchip: ksz9477: implement MTU configuration This chips supports two ways to configure max MTU size: - by setting SW_LEGAL_PACKET_DISABLE bit: if this bit is 0 allowed packed size will be between 64 and bytes 1518. If this bit is 1, it will accept packets up to 2000 bytes. - by setting SW_JUMBO_PACKET bit. If this bit is set, the chip will ignore SW_LEGAL_PACKET_DISABLE value and use REG_SW_MTU__2 register to configure MTU size. Current driver has disabled SW_JUMBO_PACKET bit and activates SW_LEGAL_PACKET_DISABLE. So the switch will pass all packets up to 2000 without any way to configure it. By providing port_change_mtu we are switch to SW_JUMBO_PACKET way and will be able to configure MTU up to ~9000. Signed-off-by: Oleksij Rempel Reviewed-by: Vladimir Oltean Link: https://lore.kernel.org/r/20220308135857.1119028-1-o.rempel@pengutronix.de Signed-off-by: Jakub Kicinski --- drivers/net/dsa/microchip/ksz9477.c | 36 +++++++++++++++++++++++++++++++-- drivers/net/dsa/microchip/ksz9477_reg.h | 3 +++ drivers/net/dsa/microchip/ksz_common.h | 1 + 3 files changed, 38 insertions(+), 2 deletions(-) diff --git a/drivers/net/dsa/microchip/ksz9477.c b/drivers/net/dsa/microchip/ksz9477.c index 94ad6d9504f4..a4699481c746 100644 --- a/drivers/net/dsa/microchip/ksz9477.c +++ b/drivers/net/dsa/microchip/ksz9477.c @@ -11,6 +11,7 @@ #include #include #include +#include #include #include @@ -182,6 +183,29 @@ static void ksz9477_port_cfg32(struct ksz_device *dev, int port, int offset, bits, set ? bits : 0); } +static int ksz9477_change_mtu(struct dsa_switch *ds, int port, int mtu) +{ + struct ksz_device *dev = ds->priv; + u16 frame_size, max_frame = 0; + int i; + + frame_size = mtu + VLAN_ETH_HLEN + ETH_FCS_LEN; + + /* Cache the per-port MTU setting */ + dev->ports[port].max_frame = frame_size; + + for (i = 0; i < dev->port_cnt; i++) + max_frame = max(max_frame, dev->ports[i].max_frame); + + return regmap_update_bits(dev->regmap[1], REG_SW_MTU__2, + REG_SW_MTU_MASK, max_frame); +} + +static int ksz9477_max_mtu(struct dsa_switch *ds, int port) +{ + return KSZ9477_MAX_FRAME_SIZE - VLAN_ETH_HLEN - ETH_FCS_LEN; +} + static int ksz9477_wait_vlan_ctrl_ready(struct ksz_device *dev) { unsigned int val; @@ -1416,8 +1440,14 @@ static int ksz9477_setup(struct dsa_switch *ds) /* Do not work correctly with tail tagging. */ ksz_cfg(dev, REG_SW_MAC_CTRL_0, SW_CHECK_LENGTH, false); - /* accept packet up to 2000bytes */ - ksz_cfg(dev, REG_SW_MAC_CTRL_1, SW_LEGAL_PACKET_DISABLE, true); + /* Enable REG_SW_MTU__2 reg by setting SW_JUMBO_PACKET */ + ksz_cfg(dev, REG_SW_MAC_CTRL_1, SW_JUMBO_PACKET, true); + + /* Now we can configure default MTU value */ + ret = regmap_update_bits(dev->regmap[1], REG_SW_MTU__2, REG_SW_MTU_MASK, + VLAN_ETH_FRAME_LEN + ETH_FCS_LEN); + if (ret) + return ret; ksz9477_config_cpu_port(ds); @@ -1464,6 +1494,8 @@ static const struct dsa_switch_ops ksz9477_switch_ops = { .port_mirror_add = ksz9477_port_mirror_add, .port_mirror_del = ksz9477_port_mirror_del, .get_stats64 = ksz9477_get_stats64, + .port_change_mtu = ksz9477_change_mtu, + .port_max_mtu = ksz9477_max_mtu, }; static u32 ksz9477_get_port_addr(int port, int offset) diff --git a/drivers/net/dsa/microchip/ksz9477_reg.h b/drivers/net/dsa/microchip/ksz9477_reg.h index 16939f29faa5..0bd58467181f 100644 --- a/drivers/net/dsa/microchip/ksz9477_reg.h +++ b/drivers/net/dsa/microchip/ksz9477_reg.h @@ -176,6 +176,7 @@ #define REG_SW_MAC_ADDR_5 0x0307 #define REG_SW_MTU__2 0x0308 +#define REG_SW_MTU_MASK GENMASK(13, 0) #define REG_SW_ISP_TPID__2 0x030A @@ -1662,4 +1663,6 @@ /* 148,800 frames * 67 ms / 100 */ #define BROADCAST_STORM_VALUE 9969 +#define KSZ9477_MAX_FRAME_SIZE 9000 + #endif /* KSZ9477_REGS_H */ diff --git a/drivers/net/dsa/microchip/ksz_common.h b/drivers/net/dsa/microchip/ksz_common.h index 4ff0a159ce3c..fa39ee73cbd2 100644 --- a/drivers/net/dsa/microchip/ksz_common.h +++ b/drivers/net/dsa/microchip/ksz_common.h @@ -41,6 +41,7 @@ struct ksz_port { struct ksz_port_mib mib; phy_interface_t interface; + u16 max_frame; }; struct ksz_device { -- 2.11.0