From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.gentoo.org (woodpecker.gentoo.org [140.211.166.183]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 75829284663; Tue, 27 Jan 2026 02:05:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=140.211.166.183 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769479540; cv=none; b=e/irMRoe9djlNHbL5vEbHUGn5zK3UVEfRRNisqZXZIgjZ7ylIobJUYu32Hcmt9oOCZ/D5d28AWmTyjuBMcp06uJDIK9/gL6fMDLbDMktgtoMQmoldQJxfzRAjiXdtS0QcG9FDNIklqHqX5V3RnRksMBCJejDe6AJTdkj/8bIWko= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769479540; c=relaxed/simple; bh=jtCdFaeN7M/y+/pP+4rZ2c4E1Jn0waySsAtKkf43YI4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=gBMeRFDTN1aDAkEnDFfP8mgDDLK0MvkGk7EZoFnGb8Ylbd9JWsltBVxJVwSmDGGaIy2ypLErn1zEwennVdFbzUoU9N0zlyz0BMsIbZpzmLOkBpp3tm99juhKV3tFJ7VkZYkCbaMW8OfqnX5cIyvpNvYkyd1Mz/krYJp5jpJeTDo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gentoo.org; spf=pass smtp.mailfrom=gentoo.org; arc=none smtp.client-ip=140.211.166.183 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gentoo.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gentoo.org Received: from localhost (unknown [116.232.27.242]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange secp256r1 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: dlan) by smtp.gentoo.org (Postfix) with ESMTPSA id BFB16335D2F; Tue, 27 Jan 2026 02:05:36 +0000 (UTC) Date: Tue, 27 Jan 2026 10:05:26 +0800 From: Yixun Lan To: Tomas Hlavacek Cc: netdev@vger.kernel.org, linux-riscv@lists.infradead.org, spacemit@lists.linux.dev, linux-kernel@vger.kernel.org, stable@vger.kernel.org, "David S . Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Andrew Lunn , Yixun Lan , Vivian Wang Subject: Re: [PATCH net v2] net: spacemit: k1-emac: program frame size registers for jumbo frames Message-ID: <20260127020526-GYA88966@gentoo.org> References: <20260126135919.77168-1-tmshlvck@gmail.com> <20260126171449.83288-1-tmshlvck@gmail.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260126171449.83288-1-tmshlvck@gmail.com> Hi Tomas, On 18:14 Mon 26 Jan , Tomas Hlavacek wrote: > The driver allows changing MTU up to 4K via emac_change_mtu() and > allocates appropriately sized DMA buffers, but it never programs the > MAC_MAXIMUM_FRAME_SIZE and MAC_RECEIVE_JABBER_SIZE registers. > > This causes the MAC hardware to reject frames larger than the default > 1518 bytes, even when larger buffers are allocated. Frames exceeding > the default size trigger jabber errors and are discarded. > > Fixes: bfec6d7f2001 ("net: spacemit: Add K1 Ethernet MAC") > Cc: stable@vger.kernel.org > Signed-off-by: Tomas Hlavacek > --- > v2: Added Fixes tag and Cc stable. > > drivers/net/ethernet/spacemit/k1_emac.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/drivers/net/ethernet/spacemit/k1_emac.c b/drivers/net/ethernet/spacemit/k1_emac.c > index 220eb5ce7583..31b1bdb2827e 100644 > --- a/drivers/net/ethernet/spacemit/k1_emac.c > +++ b/drivers/net/ethernet/spacemit/k1_emac.c > @@ -228,6 +228,12 @@ static void emac_init_hw(struct emac_priv *priv) > DEFAULT_TX_THRESHOLD); > emac_wr(priv, MAC_RECEIVE_PACKET_START_THRESHOLD, DEFAULT_RX_THRESHOLD); > > + /* Set maximum frame size and jabber size based on configured buffer > + * size. > + */ > + emac_wr(priv, MAC_MAXIMUM_FRAME_SIZE, priv->dma_buf_sz); > + emac_wr(priv, MAC_RECEIVE_JABBER_SIZE, priv->dma_buf_sz); > + I'm no expert here, but just notice there is additional MAC_TRANSMIT_JABBER_SIZE register which is no need to set? or is the problem on receive side only? > /* Configure flow control (enabled in emac_adjust_link() later) */ > emac_set_mac_addr_reg(priv, fc_dest_addr, MAC_FC_SOURCE_ADDRESS_HIGH); > emac_wr(priv, MAC_FC_PAUSE_HIGH_THRESHOLD, DEFAULT_FC_FIFO_HIGH); > -- > 2.52.0 > -- Yixun Lan (dlan)