From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 672631BE846; Tue, 2 Jul 2024 17:28:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719941307; cv=none; b=Mjmbhn2foxQIz+xLeldPaeXkB+ytf6ojZ3Hjbgs9n2CPXe+XF9pGz8a5QGUxMDTpZ4Lu7nlJwDfuInOEP05V/ZJgAh2n92qB8md0VKyKMt2Wngm1VU1w6oLNtaglAKx9zpbKYsRmpO7u+GiCDRIUjE84GDgyGSN9idbf7xoZP/w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719941307; c=relaxed/simple; bh=DX4DtjZ/VuZ+QSLSIPJ0/Omm5+8vlK0MRB8pfry77pw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=E5vAV/cY9q1Oq3EmZ4c1Bmgr2/2KWxiWX5TEdjR2LyK27aLDGa1BQmuNa0GzHCRdOWE7FOHzPCp4bU31P5t5A0Rj3EQiMwshjVmVqRL24G5n40RL3t6cejwjAaWFzddmIeXozSoNbaSpnHLZNPSBS2YKl9dGzpYNQ2Z6erGokbs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=eoP7dV0S; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="eoP7dV0S" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B93BFC4AF07; Tue, 2 Jul 2024 17:28:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1719941307; bh=DX4DtjZ/VuZ+QSLSIPJ0/Omm5+8vlK0MRB8pfry77pw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=eoP7dV0SQCxDNOd2bWLpwXcdJ10xJmwnOzbU7bH3ha/FfaphKydXRCIPN8gDWCORt 5M5sTy4hdqHuil400xs/qseydfX+toOegDfYeaY36jOvtUOsoPw/kzdanrh0MzBc/h GWN3zITfqZzn3/fttIVWFhx0BEppHdShMmxknbPA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Enguerrand de Ribaucourt , Woojung Huh , Arun Ramadoss , Andrew Lunn , "David S. Miller" , Sasha Levin Subject: [PATCH 6.1 025/128] net: dsa: microchip: use collision based back pressure mode Date: Tue, 2 Jul 2024 19:03:46 +0200 Message-ID: <20240702170227.184486904@linuxfoundation.org> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240702170226.231899085@linuxfoundation.org> References: <20240702170226.231899085@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Enguerrand de Ribaucourt [ Upstream commit d963c95bc9840d070a788c35e41b715a648717f7 ] Errata DS80000758 states that carrier sense back pressure mode can cause link down issues in 100BASE-TX half duplex mode. The datasheet also recommends to always use the collision based back pressure mode. Fixes: b987e98e50ab ("dsa: add DSA switch driver for Microchip KSZ9477") Signed-off-by: Enguerrand de Ribaucourt Reviewed-by: Woojung Huh Acked-by: Arun Ramadoss Reviewed-by: Andrew Lunn Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/dsa/microchip/ksz9477.c | 4 ++++ drivers/net/dsa/microchip/ksz9477_reg.h | 1 + 2 files changed, 5 insertions(+) diff --git a/drivers/net/dsa/microchip/ksz9477.c b/drivers/net/dsa/microchip/ksz9477.c index 9181be2d8abb2..e9fa92a833227 100644 --- a/drivers/net/dsa/microchip/ksz9477.c +++ b/drivers/net/dsa/microchip/ksz9477.c @@ -1150,6 +1150,10 @@ int ksz9477_setup(struct dsa_switch *ds) /* Enable REG_SW_MTU__2 reg by setting SW_JUMBO_PACKET */ ksz_cfg(dev, REG_SW_MAC_CTRL_1, SW_JUMBO_PACKET, true); + /* Use collision based back pressure mode. */ + ksz_cfg(dev, REG_SW_MAC_CTRL_1, SW_BACK_PRESSURE, + SW_BACK_PRESSURE_COLLISION); + /* 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); diff --git a/drivers/net/dsa/microchip/ksz9477_reg.h b/drivers/net/dsa/microchip/ksz9477_reg.h index 53c68d286dd3a..04086e9ab0a0f 100644 --- a/drivers/net/dsa/microchip/ksz9477_reg.h +++ b/drivers/net/dsa/microchip/ksz9477_reg.h @@ -267,6 +267,7 @@ #define REG_SW_MAC_CTRL_1 0x0331 #define SW_BACK_PRESSURE BIT(5) +#define SW_BACK_PRESSURE_COLLISION 0 #define FAIR_FLOW_CTRL BIT(4) #define NO_EXC_COLLISION_DROP BIT(3) #define SW_JUMBO_PACKET BIT(2) -- 2.43.0