Commit abef8495 authored by Jakub Kicinski's avatar Jakub Kicinski
Browse files

Merge branch 'mlxsw-handle-mtu-values' 

Petr Machata says:

====================
mlxsw: Handle MTU values

Amit Cohen writes:

The driver uses two values for maximum MTU, but neither is accurate.
In addition, the value which is configured to hardware is not calculated
correctly. Handle these issues and expose accurate values for minimum
and maximum MTU per netdevice.

Add test cases to check that the exposed values are really supported.

Patch set overview:
Patches #1-#3 set the driver to use accurate values for MTU
Patch #4 aligns the driver to always use the same value for maximum MTU
Patch #5 adds a test
====================

Link: https://lore.kernel.org/r/cover.1718275854.git.petrm@nvidia.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parents afc5625e 4be3dcc9

drivers/net/ethernet/mellanox/mlxsw/port.h

+2 −1
Original line number Diff line number Diff line
@@ -6,7 +6,8 @@ 


#include <linux/types.h>



#define MLXSW_PORT_MAX_MTU		10000

#define MLXSW_PORT_MAX_MTU		(10 * 1024)

#define MLXSW_PORT_ETH_FRAME_HDR	(ETH_HLEN + VLAN_HLEN + ETH_FCS_LEN)



#define MLXSW_PORT_DEFAULT_VID		1

drivers/net/ethernet/mellanox/mlxsw/spectrum.c

+3 −28
Original line number Diff line number Diff line
@@ -405,29 +405,12 @@ static int mlxsw_sp_port_dev_addr_init(struct mlxsw_sp_port *mlxsw_sp_port) 
					  mlxsw_sp_port->dev->dev_addr);

}



static int mlxsw_sp_port_max_mtu_get(struct mlxsw_sp_port *mlxsw_sp_port, int *p_max_mtu)

{

	struct mlxsw_sp *mlxsw_sp = mlxsw_sp_port->mlxsw_sp;

	char pmtu_pl[MLXSW_REG_PMTU_LEN];

	int err;



	mlxsw_reg_pmtu_pack(pmtu_pl, mlxsw_sp_port->local_port, 0);

	err = mlxsw_reg_query(mlxsw_sp->core, MLXSW_REG(pmtu), pmtu_pl);

	if (err)

		return err;



	*p_max_mtu = mlxsw_reg_pmtu_max_mtu_get(pmtu_pl);

	return 0;

}



static int mlxsw_sp_port_mtu_set(struct mlxsw_sp_port *mlxsw_sp_port, u16 mtu)

{

	struct mlxsw_sp *mlxsw_sp = mlxsw_sp_port->mlxsw_sp;

	char pmtu_pl[MLXSW_REG_PMTU_LEN];



	mtu += MLXSW_TXHDR_LEN + ETH_HLEN;

	if (mtu > mlxsw_sp_port->max_mtu)

		return -EINVAL;

	mtu += MLXSW_PORT_ETH_FRAME_HDR;



	mlxsw_reg_pmtu_pack(pmtu_pl, mlxsw_sp_port->local_port, mtu);

	return mlxsw_reg_write(mlxsw_sp->core, MLXSW_REG(pmtu), pmtu_pl);
@@ -1697,8 +1680,8 @@ static int mlxsw_sp_port_create(struct mlxsw_sp *mlxsw_sp, u16 local_port, 
			 NETIF_F_HW_VLAN_CTAG_FILTER | NETIF_F_HW_TC;

	dev->hw_features |= NETIF_F_HW_TC | NETIF_F_LOOPBACK;



	dev->min_mtu = 0;

	dev->max_mtu = ETH_MAX_MTU;

	dev->min_mtu = ETH_MIN_MTU;

	dev->max_mtu = MLXSW_PORT_MAX_MTU - MLXSW_PORT_ETH_FRAME_HDR;



	/* Each packet needs to have a Tx header (metadata) on top all other

	 * headers.
@@ -1727,13 +1710,6 @@ static int mlxsw_sp_port_create(struct mlxsw_sp *mlxsw_sp, u16 local_port, 
		goto err_max_speed_get;

	}



	err = mlxsw_sp_port_max_mtu_get(mlxsw_sp_port, &mlxsw_sp_port->max_mtu);

	if (err) {

		dev_err(mlxsw_sp->bus_info->dev, "Port %d: Failed to get maximum MTU\n",

			mlxsw_sp_port->local_port);

		goto err_port_max_mtu_get;

	}



	err = mlxsw_sp_port_mtu_set(mlxsw_sp_port, ETH_DATA_LEN);

	if (err) {

		dev_err(mlxsw_sp->bus_info->dev, "Port %d: Failed to set MTU\n",
@@ -1877,7 +1853,6 @@ static int mlxsw_sp_port_create(struct mlxsw_sp *mlxsw_sp, u16 local_port, 
err_port_buffers_init:

err_port_admin_status_set:

err_port_mtu_set:

err_port_max_mtu_get:

err_max_speed_get:

err_port_speed_by_width_set:

err_port_system_port_mapping_set:

drivers/net/ethernet/mellanox/mlxsw/spectrum.h

+0 −1
Original line number Diff line number Diff line
@@ -359,7 +359,6 @@ struct mlxsw_sp_port { 
		u16 egr_types;

		struct mlxsw_sp_ptp_port_stats stats;

	} ptp;

	int max_mtu;

	u32 max_speed;

	struct mlxsw_sp_hdroom *hdroom;

	u64 module_overheat_initial_val;

drivers/net/ethernet/mellanox/mlxsw/spectrum_buffers.c

+6 −2
Original line number Diff line number Diff line
@@ -399,11 +399,13 @@ void mlxsw_sp_hdroom_bufs_reset_sizes(struct mlxsw_sp_port *mlxsw_sp_port, 
				      struct mlxsw_sp_hdroom *hdroom)

{

	struct mlxsw_sp *mlxsw_sp = mlxsw_sp_port->mlxsw_sp;

	unsigned int max_mtu = mlxsw_sp_port->dev->max_mtu;

	u16 reserve_cells;

	int i;



	max_mtu += MLXSW_PORT_ETH_FRAME_HDR;

	/* Internal buffer. */

	reserve_cells = mlxsw_sp_hdroom_int_buf_size_get(mlxsw_sp, mlxsw_sp_port->max_mtu,

	reserve_cells = mlxsw_sp_hdroom_int_buf_size_get(mlxsw_sp, max_mtu,

							 mlxsw_sp_port->max_speed);

	reserve_cells = mlxsw_sp_port_headroom_8x_adjust(mlxsw_sp_port, reserve_cells);

	hdroom->int_buf.reserve_cells = reserve_cells;
@@ -613,7 +615,9 @@ static int mlxsw_sp_port_headroom_init(struct mlxsw_sp_port *mlxsw_sp_port) 
	mlxsw_sp_hdroom_bufs_reset_sizes(mlxsw_sp_port, &hdroom);



	/* Buffer 9 is used for control traffic. */

	size9 = mlxsw_sp_port_headroom_8x_adjust(mlxsw_sp_port, mlxsw_sp_port->max_mtu);

	size9 = mlxsw_sp_port_headroom_8x_adjust(mlxsw_sp_port,

						 mlxsw_sp_port->dev->max_mtu +

						 MLXSW_PORT_ETH_FRAME_HDR);

	hdroom.bufs.buf[9].size_cells = mlxsw_sp_bytes_cells(mlxsw_sp, size9);



	return __mlxsw_sp_hdroom_configure(mlxsw_sp_port, &hdroom, true);

tools/testing/selftests/net/forwarding/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -39,6 +39,7 @@ TEST_PROGS = bridge_fdb_learning_limit.sh \ 
	ipip_hier_gre.sh \

	lib_sh_test.sh \

	local_termination.sh \

	min_max_mtu.sh \

	mirror_gre_bound.sh \

	mirror_gre_bridge_1d.sh \

	mirror_gre_bridge_1d_vlan.sh \