Commit 609c767f authored by Paolo Abeni's avatar Paolo Abeni
Browse files

Merge branch 'net-dsa-realtek-two-rtl8366rb-fixes' 



Linus Walleij says:

====================
net: dsa: realtek: Two RTL8366RB fixes

These minor fixes were found while digging into other
issues: a weirdly named variable and bogus MTU handling.
Fix it up.

Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
====================

Link: https://lore.kernel.org/r/20231209-rtl8366rb-mtu-fix-v1-0-df863e2b2b2a@linaro.org


Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
parents 26c79ec9 d577ca42

drivers/net/dsa/realtek/rtl8366rb.c

+36 −23
Original line number Diff line number Diff line
@@ -15,6 +15,7 @@ 
#include <linux/bitops.h>

#include <linux/etherdevice.h>

#include <linux/if_bridge.h>

#include <linux/if_vlan.h>

#include <linux/interrupt.h>

#include <linux/irqdomain.h>

#include <linux/irqchip/chained_irq.h>
@@ -117,10 +118,11 @@ 
	RTL8366RB_STP_STATE((port), RTL8366RB_STP_MASK)



/* CPU port control reg */

#define RTL8368RB_CPU_CTRL_REG		0x0061

#define RTL8368RB_CPU_PORTS_MSK		0x00FF

#define RTL8366RB_CPU_CTRL_REG		0x0061

#define RTL8366RB_CPU_PORTS_MSK		0x00FF

/* Disables inserting custom tag length/type 0x8899 */

#define RTL8368RB_CPU_NO_TAG		BIT(15)

#define RTL8366RB_CPU_NO_TAG		BIT(15)

#define RTL8366RB_CPU_TAG_SIZE		4



#define RTL8366RB_SMAR0			0x0070 /* bits 0..15 */

#define RTL8366RB_SMAR1			0x0071 /* bits 16..31 */
@@ -912,10 +914,10 @@ static int rtl8366rb_setup(struct dsa_switch *ds) 


	/* Enable CPU port with custom DSA tag 8899.

	 *

	 * If you set RTL8368RB_CPU_NO_TAG (bit 15) in this registers

	 * If you set RTL8366RB_CPU_NO_TAG (bit 15) in this register

	 * the custom tag is turned off.

	 */

	ret = regmap_update_bits(priv->map, RTL8368RB_CPU_CTRL_REG,

	ret = regmap_update_bits(priv->map, RTL8366RB_CPU_CTRL_REG,

				 0xFFFF,

				 BIT(priv->cpu_port));

	if (ret)
@@ -928,15 +930,19 @@ static int rtl8366rb_setup(struct dsa_switch *ds) 
	if (ret)

		return ret;



	/* Set maximum packet length to 1536 bytes */

	/* Set default maximum packet length to 1536 bytes */

	ret = regmap_update_bits(priv->map, RTL8366RB_SGCR,

				 RTL8366RB_SGCR_MAX_LENGTH_MASK,

				 RTL8366RB_SGCR_MAX_LENGTH_1536);

	if (ret)

		return ret;

	for (i = 0; i < RTL8366RB_NUM_PORTS; i++)

		/* layer 2 size, see rtl8366rb_change_mtu() */

		rb->max_mtu[i] = 1532;

	for (i = 0; i < RTL8366RB_NUM_PORTS; i++) {

		if (i == priv->cpu_port)

			/* CPU port need to also accept the tag */

			rb->max_mtu[i] = ETH_DATA_LEN + RTL8366RB_CPU_TAG_SIZE;

		else

			rb->max_mtu[i] = ETH_DATA_LEN;

	}



	/* Disable learning for all ports */

	ret = regmap_write(priv->map, RTL8366RB_PORT_LEARNDIS_CTRL,
@@ -1441,24 +1447,29 @@ static int rtl8366rb_change_mtu(struct dsa_switch *ds, int port, int new_mtu) 
	/* Roof out the MTU for the entire switch to the greatest

	 * common denominator: the biggest set for any one port will

	 * be the biggest MTU for the switch.

	 *

	 * The first setting, 1522 bytes, is max IP packet 1500 bytes,

	 * plus ethernet header, 1518 bytes, plus CPU tag, 4 bytes.

	 * This function should consider the parameter an SDU, so the

	 * MTU passed for this setting is 1518 bytes. The same logic

	 * of subtracting the DSA tag of 4 bytes apply to the other

	 * settings.

	 */

	max_mtu = 1518;

	max_mtu = ETH_DATA_LEN;

	for (i = 0; i < RTL8366RB_NUM_PORTS; i++) {

		if (rb->max_mtu[i] > max_mtu)

			max_mtu = rb->max_mtu[i];

	}

	if (max_mtu <= 1518)



	/* Translate to layer 2 size.

	 * Add ethernet and (possible) VLAN headers, and checksum to the size.

	 * For ETH_DATA_LEN (1500 bytes) this will add up to 1522 bytes.

	 */

	max_mtu += VLAN_ETH_HLEN;

	max_mtu += ETH_FCS_LEN;



	if (max_mtu <= 1522)

		len = RTL8366RB_SGCR_MAX_LENGTH_1522;

	else if (max_mtu > 1518 && max_mtu <= 1532)

	else if (max_mtu > 1522 && max_mtu <= 1536)

		/* This will be the most common default if using VLAN and

		 * CPU tagging on a port as both VLAN and CPU tag will

		 * result in 1518 + 4 + 4 = 1526 bytes.

		 */

		len = RTL8366RB_SGCR_MAX_LENGTH_1536;

	else if (max_mtu > 1532 && max_mtu <= 1548)

	else if (max_mtu > 1536 && max_mtu <= 1552)

		len = RTL8366RB_SGCR_MAX_LENGTH_1552;

	else

		len = RTL8366RB_SGCR_MAX_LENGTH_16000;
@@ -1470,10 +1481,12 @@ static int rtl8366rb_change_mtu(struct dsa_switch *ds, int port, int new_mtu) 


static int rtl8366rb_max_mtu(struct dsa_switch *ds, int port)

{

	/* The max MTU is 16000 bytes, so we subtract the CPU tag

	 * and the max presented to the system is 15996 bytes.

	/* The max MTU is 16000 bytes, so we subtract the ethernet

	 * headers with VLAN and checksum and arrive at

	 * 16000 - 18 - 4 = 15978. This does not include the CPU tag

	 * since that is added to the requested MTU by the DSA framework.

	 */

	return 15996;

	return 16000 - VLAN_ETH_HLEN - ETH_FCS_LEN;

}



static int rtl8366rb_get_vlan_4k(struct realtek_priv *priv, u32 vid,