Commit 262bfba8 authored by Tristram Ha's avatar Tristram Ha Committed by Jakub Kicinski
Browse files

net: dsa: microchip: Fix KSZ9477 set_ageing_time function 



The aging count is not a simple 11-bit value but comprises a 3-bit
multiplier and an 8-bit second count.  The code tries to use the
original multiplier which is 4 as the second count is still 300 seconds
by default.

Fixes: 2c119d99 ("net: dsa: microchip: add the support for set_ageing_time")
Signed-off-by: default avatarTristram Ha <tristram.ha@microchip.com>
Reviewed-by: default avatarAndrew Lunn <andrew@lunn.ch>
Link: https://patch.msgid.link/20241218020224.70590-2-Tristram.Ha@microchip.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 25c6a5ab

drivers/net/dsa/microchip/ksz9477.c

+36 −11
Original line number Diff line number Diff line
@@ -2,7 +2,7 @@ 
/*

 * Microchip KSZ9477 switch driver main logic

 *

 * Copyright (C) 2017-2019 Microchip Technology Inc.

 * Copyright (C) 2017-2024 Microchip Technology Inc.

 */



#include <linux/kernel.h>
@@ -983,26 +983,51 @@ void ksz9477_get_caps(struct ksz_device *dev, int port, 
int ksz9477_set_ageing_time(struct ksz_device *dev, unsigned int msecs)

{

	u32 secs = msecs / 1000;

	u8 value;

	u8 data;

	u8 data, mult, value;

	u32 max_val;

	int ret;



	value = FIELD_GET(SW_AGE_PERIOD_7_0_M, secs);

#define MAX_TIMER_VAL	((1 << 8) - 1)



	ret = ksz_write8(dev, REG_SW_LUE_CTRL_3, value);

	if (ret < 0)

		return ret;

	/* The aging timer comprises a 3-bit multiplier and an 8-bit second

	 * value.  Either of them cannot be zero.  The maximum timer is then

	 * 7 * 255 = 1785 seconds.

	 */

	if (!secs)

		secs = 1;



	data = FIELD_GET(SW_AGE_PERIOD_10_8_M, secs);

	/* Return error if too large. */

	else if (secs > 7 * MAX_TIMER_VAL)

		return -EINVAL;



	ret = ksz_read8(dev, REG_SW_LUE_CTRL_0, &value);

	if (ret < 0)

		return ret;



	/* Check whether there is need to update the multiplier. */

	mult = FIELD_GET(SW_AGE_CNT_M, value);

	max_val = MAX_TIMER_VAL;

	if (mult > 0) {

		/* Try to use the same multiplier already in the register as

		 * the hardware default uses multiplier 4 and 75 seconds for

		 * 300 seconds.

		 */

		max_val = DIV_ROUND_UP(secs, mult);

		if (max_val > MAX_TIMER_VAL || max_val * mult != secs)

			max_val = MAX_TIMER_VAL;

	}



	data = DIV_ROUND_UP(secs, max_val);

	if (mult != data) {

		value &= ~SW_AGE_CNT_M;

		value |= FIELD_PREP(SW_AGE_CNT_M, data);

		ret = ksz_write8(dev, REG_SW_LUE_CTRL_0, value);

		if (ret < 0)

			return ret;

	}



	return ksz_write8(dev, REG_SW_LUE_CTRL_0, value);

	value = DIV_ROUND_UP(secs, data);

	return ksz_write8(dev, REG_SW_LUE_CTRL_3, value);

}



void ksz9477_port_queue_split(struct ksz_device *dev, int port)

drivers/net/dsa/microchip/ksz9477_reg.h

+1 −3
Original line number Diff line number Diff line
@@ -2,7 +2,7 @@ 
/*

 * Microchip KSZ9477 register definitions

 *

 * Copyright (C) 2017-2018 Microchip Technology Inc.

 * Copyright (C) 2017-2024 Microchip Technology Inc.

 */



#ifndef __KSZ9477_REGS_H
@@ -165,8 +165,6 @@ 
#define SW_VLAN_ENABLE			BIT(7)

#define SW_DROP_INVALID_VID		BIT(6)

#define SW_AGE_CNT_M			GENMASK(5, 3)

#define SW_AGE_CNT_S			3

#define SW_AGE_PERIOD_10_8_M		GENMASK(10, 8)

#define SW_RESV_MCAST_ENABLE		BIT(2)

#define SW_HASH_OPTION_M		0x03

#define SW_HASH_OPTION_CRC		1