linux-kernel - Re: [RESEND net-next v5 2/4] net: phy: realtek: Clean up RTL8211E ExtPage access

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <Z_VvOG91oPZZejye@a98shuttle.de>
Date: Tue, 8 Apr 2025 20:47:20 +0200
From: Michael Klein <michael@...sekall.de>
To: Joe Damato <jdamato@...tly.com>, Andrew Lunn <andrew@...n.ch>,
	Heiner Kallweit <hkallweit1@...il.com>,
	Russell King <linux@...linux.org.uk>,
	"David S. Miller" <davem@...emloft.net>,
	Eric Dumazet <edumazet@...gle.com>,
	Jakub Kicinski <kuba@...nel.org>, Paolo Abeni <pabeni@...hat.com>,
	netdev@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [RESEND net-next v5 2/4] net: phy: realtek: Clean up RTL8211E
 ExtPage access

On Mon, Apr 07, 2025 at 07:56:14PM -0700, Joe Damato wrote:
>> - Factor out RTL8211E extension page access code to
>>   rtl8211e_modify_ext_page() and clean up rtl8211e_config_init()
>>
>> Signed-off-by: Michael Klein <michael@...sekall.de>
>> ---
>>  drivers/net/phy/realtek/realtek_main.c | 38 +++++++++++++++-----------
>>  1 file changed, 22 insertions(+), 16 deletions(-)
>>
>> diff --git a/drivers/net/phy/realtek/realtek_main.c b/drivers/net/phy/realtek/realtek_main.c
>> index b27c0f995e56..e60c18551a4e 100644
>> --- a/drivers/net/phy/realtek/realtek_main.c
>> +++ b/drivers/net/phy/realtek/realtek_main.c
>> @@ -37,9 +37,11 @@
>>
>>  #define RTL821x_INSR				0x13
>>
>> -#define RTL821x_EXT_PAGE_SELECT			0x1e
>>  #define RTL821x_PAGE_SELECT			0x1f
>>
>> +#define RTL8211E_EXT_PAGE_SELECT		0x1e
>> +#define RTL8211E_SET_EXT_PAGE			0x07
>> +
>>  #define RTL8211E_CTRL_DELAY			BIT(13)
>>  #define RTL8211E_TX_DELAY			BIT(12)
>>  #define RTL8211E_RX_DELAY			BIT(11)
>> @@ -135,6 +137,21 @@ static int rtl821x_write_page(struct phy_device *phydev, int page)
>>  	return __phy_write(phydev, RTL821x_PAGE_SELECT, page);
>>  }
>>
>> +static int rtl8211e_modify_ext_page(struct phy_device *phydev, u16 ext_page,
>> +				    u32 regnum, u16 mask, u16 set)
>> +{
>> +	int oldpage, ret = 0;
>> +
>> +	oldpage = phy_select_page(phydev, RTL8211E_SET_EXT_PAGE);
>> +	if (oldpage >= 0) {
>> +		ret = __phy_write(phydev, RTL8211E_EXT_PAGE_SELECT, ext_page);
>> +		if (ret == 0)
>> +			ret = __phy_modify(phydev, regnum, mask, set);
>> +	}
>> +
>> +	return phy_restore_page(phydev, oldpage, ret);
>> +}
>> +
>>  static int rtl821x_probe(struct phy_device *phydev)
>>  {
>>  	struct device *dev = &phydev->mdio.dev;
>> @@ -607,7 +624,9 @@ static int rtl8211f_led_hw_control_set(struct phy_device *phydev, u8 index,
>>
>>  static int rtl8211e_config_init(struct phy_device *phydev)
>>  {
>> -	int ret = 0, oldpage;
>> +	const u16 delay_mask = RTL8211E_CTRL_DELAY |
>> +			       RTL8211E_TX_DELAY |
>> +			       RTL8211E_RX_DELAY;
>>  	u16 val;
>>
>>  	/* enable TX/RX delay for rgmii-* modes, and disable them for rgmii. */
>> @@ -637,20 +656,7 @@ static int rtl8211e_config_init(struct phy_device *phydev)
>>  	 * 12 = RX Delay, 11 = TX Delay
>>  	 * 10:0 = Test && debug settings reserved by realtek
>>  	 */
>> -	oldpage = phy_select_page(phydev, 0x7);
>> -	if (oldpage < 0)
>> -		goto err_restore_page;
>> -
>> -	ret = __phy_write(phydev, RTL821x_EXT_PAGE_SELECT, 0xa4);
>> -	if (ret)
>> -		goto err_restore_page;
>> -
>> -	ret = __phy_modify(phydev, 0x1c, RTL8211E_CTRL_DELAY
>> -			   | RTL8211E_TX_DELAY | RTL8211E_RX_DELAY,
>> -			   val);
>> -
>> -err_restore_page:
>> -	return phy_restore_page(phydev, oldpage, ret);
>> +	return rtl8211e_modify_ext_page(phydev, 0xa4, 0x1c, delay_mask, val);
>>  }
>
>Seems good to add RTL8211E_SET_EXT_PAGE to remove a constant from
>the code. Any reason to avoid adding constants for 0xa4 and 0x1c ?

My copy of the datasheet does not document this register, so I did not
feel qualified to come up with a meaningful name.