From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 9D947C7115A for ; Wed, 18 Jun 2025 19:12:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=eTsSA5tSG0BBeG/tO1836ylFVVkJ0QYKSkBxCV3iQpM=; b=qdcJNqsgCSME6EqveDGztBrcPW pJ7TK/NpxQmb2JuvMf8v1snWooz61WwGEodAkr9LV0MjtPMRMKHYdzYvNP8Aup8E/y6RhIEmurE5D DPc8QeIvtUo5tuoGr0Xq7YBOvCIdekr3F4vBYHvv7NvHEZjLGP6zZGAlU/L9A1eJqk4wdcYTCU0u4 DW/qkV6WC5ngUrBCv+c1hWcT26+cFtFw9PAyECd57oxKRGT+5Qt6pi53YPZ1LEmrDE7jZAOOSo1Nx twrtvP67VTCHGBrfPk3c2amMHAHEVgwlbEv+pisfHIPcOVfg0pTqC30+bApdxJYlQFiDpWyUtKZ/2 IyfDJI1Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1uRyCO-0000000BA3T-0xL1; Wed, 18 Jun 2025 19:11:52 +0000 Received: from desiato.infradead.org ([2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1uRwne-0000000Atc9-12Pl; Wed, 18 Jun 2025 17:42:14 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=eTsSA5tSG0BBeG/tO1836ylFVVkJ0QYKSkBxCV3iQpM=; b=gqcyXCKAIjcERbqUt1Ljgjsk0p 3h6fxO0etkd70l/E21ZfcZ45FWeA/IFIuOtBqiyOIRE0/bKzDpMLSBQBFgsViCMjvoayPIaiyz4DN kjkzLI8vgbewwVzsUDgP/+TCmo8KFLJyJddjOBNk+5+OVbrYVha1Co7eq3M0i3V8HSPHo4U7UHm1p TcbWrtj9/mVSTxDaOtM67HZa56xrIy+GPxGYqNr1t5s4KEpax2D111d5ZlWO5Rv4hcC/wAvjQ9VsI GUrjRAMsivP1e18oNpApsVVEsSuneLs8l3kOJSgoSDLioF/+6kcY1CF89IrH3gfQEwod6AamJO4ce ZNa8lGYw==; Received: from pidgin.makrotopia.org ([2a07:2ec0:3002::65]) by desiato.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1uRwnb-00000004Eax-3SdL; Wed, 18 Jun 2025 17:42:13 +0000 Received: from local by pidgin.makrotopia.org with esmtpsa (TLS1.3:TLS_AES_256_GCM_SHA384:256) (Exim 4.98.2) (envelope-from ) id 1uRwez-000000004uy-0gef; Wed, 18 Jun 2025 17:41:59 +0000 Date: Wed, 18 Jun 2025 19:41:50 +0200 From: Daniel Golle To: Frank Wunderlich Cc: Felix Fietkau , Sean Wang , Lorenzo Bianconi , Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Matthias Brugger , AngeloGioacchino Del Regno , Frank Wunderlich , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, Simon Horman , arinc.unal@arinc9.com Subject: Re: [net-next v5 3/3] net: ethernet: mtk_eth_soc: skip first IRQ if not used Message-ID: References: <20250618130717.75839-1-linux@fw-web.de> <20250618130717.75839-4-linux@fw-web.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250618130717.75839-4-linux@fw-web.de> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250618_184211_927639_B39001BF X-CRM114-Status: GOOD ( 29.82 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, Jun 18, 2025 at 03:07:14PM +0200, Frank Wunderlich wrote: > From: Frank Wunderlich > > On SoCs without MTK_SHARED_INT capability (all except mt7621 and > mt7628) platform_get_irq() is called for the first IRQ (eth->irq[0]) > but it is never used. I know that technically MTK_SHARED_INT is a capability flag, but it's rather a non-capability. Hardware having dedicated interrupts for RX and TX is "more capable" than (older, legacy) hardware with just one shared interrupt for both... So maybe better: "On SoCs with dedicated RX and TX interrupts (all except MT7621 and MT7628) ..." Reading the datasheet of some recent MediaTek SoC it is worth noting that there are 4 interrupts assigned to the frame engine and the FE_INT_GRP register can be used to assign functions to them. So technically, calling them RX and TX in DT is wrong, becaues they are fe_int0, fe_int1, fe_int2 and fe_int3, which are then assigned one or more functions by the driver using that FE_INT_GRP register. However, it's the driver then assigns QDMA TX to fe_int1 and RX to fe_int2 while leaving fe_int0 and fe_int3 unsued. That's what the magic value 0x21021000 which is written to FE_INT_GRP register does. On MT7988 and newer, in addition to those 4 frame engine interrupts there are **another 4** interrupts for PDMA, typically used to service 4 RX rings while one of the fe_int* is used to indicate TX done. > Skip the first IRQ and reduce the IRQ-count to 2. > > Signed-off-by: Frank Wunderlich > --- > v5: > - change commit title and description > v4: > - drop >2 condition as max is already 2 and drop the else continue > - update comment to explain which IRQs are taken in legacy way > --- > drivers/net/ethernet/mediatek/mtk_eth_soc.c | 12 ++++++++---- > drivers/net/ethernet/mediatek/mtk_eth_soc.h | 4 ++-- > 2 files changed, 10 insertions(+), 6 deletions(-) > > diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c > index 875e477a987b..7990c84b2b56 100644 > --- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c > +++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c > @@ -3354,10 +3354,14 @@ static int mtk_get_irqs(struct platform_device *pdev, struct mtk_eth *eth) > * the second is for TX, and the third is for RX. > */ > for (i = 0; i < MTK_FE_IRQ_NUM; i++) { > - if (MTK_HAS_CAPS(eth->soc->caps, MTK_SHARED_INT) && i > 0) > - eth->irq[i] = eth->irq[MTK_FE_IRQ_SHARED]; > - else > - eth->irq[i] = platform_get_irq(pdev, i); > + if (MTK_HAS_CAPS(eth->soc->caps, MTK_SHARED_INT)) { > + if (i == 0) This would make it even more readable: if (i == MTK_FE_IRQ_SHARED) Other than that looks good to me: Reviewed-by: Daniel Golle > + eth->irq[MTK_FE_IRQ_SHARED] = platform_get_irq(pdev, i); > + else > + eth->irq[i] = eth->irq[MTK_FE_IRQ_SHARED]; > + } else { > + eth->irq[i] = platform_get_irq(pdev, i + 1); > + } > > if (eth->irq[i] < 0) { > dev_err(&pdev->dev, "no IRQ%d resource found\n", i); > diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.h b/drivers/net/ethernet/mediatek/mtk_eth_soc.h > index 8cdf1317dff5..9261c0e13b59 100644 > --- a/drivers/net/ethernet/mediatek/mtk_eth_soc.h > +++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.h > @@ -643,8 +643,8 @@ > #define MTK_MAC_FSM(x) (0x1010C + ((x) * 0x100)) > > #define MTK_FE_IRQ_SHARED 0 > -#define MTK_FE_IRQ_TX 1 > -#define MTK_FE_IRQ_RX 2 > +#define MTK_FE_IRQ_TX 0 > +#define MTK_FE_IRQ_RX 1 > #define MTK_FE_IRQ_NUM (MTK_FE_IRQ_RX + 1) > > struct mtk_rx_dma { > -- > 2.43.0 > >