From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 E955D3BBFD9; Fri, 18 Sep 2026 03:24:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789701888; cv=none; b=YlxvVkvE2CEHDPda48IKrKTFtyOm+9ki+ulwWzU7o0llhPz7E9pL0lxxmlwM/TFuN3QWLrx5drPHhE6WDXV+u8GTjl9MypUAwBkikKjoeFGYXmmOs3MQHybGRsrt3rVFASvpOD/p+faSfXJvsHObiMqrCS547NoyW1QwfHu9wJs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789701888; c=relaxed/simple; bh=Zd85IjzkXBz8cIY1oXwsburQngP1P3LTrX3UgCD6/oQ=; h=From:Subject:To:Cc:In-Reply-To:References:Content-Type:Date: Message-Id; b=c53HWYLv+V1cgVvxifcrYh/7jl3KXKmWv6Ef3sf82eWm0dzATWEeyWFpJpi0bmvoM0fUAvqFkAhm1Co35sicy8a3uagwQJbGnRJaeMoR0xKVRF0Vgr6PfZ/oDeaRxQfrCGWfI+Zvjl/85lE70/irHHruH8MBsI/vCMFBaThQFH0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=aVtwB7e8; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="aVtwB7e8" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 815351F00893; Fri, 18 Sep 2026 03:24:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789701886; bh=Zd85IjzkXBz8cIY1oXwsburQngP1P3LTrX3UgCD6/oQ=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=aVtwB7e8YP0Q9Qwq+hFAT1a6ikqpNOvBmwlBHHDREVLKeqywP7pWlgoDnE0/3DjD3 uh2tstaArJ2JIr6RUsfp3TqsC2SwgYFQGZpu790wSOwFUO/fH4DHcABJqw/xF5uZBl a2lVFCdhmL08DbOC2YR6d6NNBSC9CJEYZR4JUncXEtgce0dM4op9sGwvQ/GpTrZh7v shghKgIG3yJa0PaKUSizCSWWA/XRYiS27gHwCJkxa9tVAuhYdnQaX+fq/C8JK8AKJV A4thbtka4YKm92vc6AsH2B3ZAXQkP2EfJxixn4kn22HTmc1kjmC6mW6krY17pYasmw HLu9Spk5Lx9RQ== From: sashiko-bot@kernel.org Subject: Re: [PATCH 08/11] PCI: dwc: Let glue drivers hide the Root Port MSI capabilities Reply-To: sashiko-reviews@lists.linux.dev To: "Koichiro Den" Cc: robh@kernel.org, wsa+renesas@sang-engineering.com, conor+dt@kernel.org, linux-pci@vger.kernel.org, devicetree@vger.kernel.org In-Reply-To: <20260918032038.2216471-9-den@valinux.co.jp> References: <20260918032038.2216471-1-den@valinux.co.jp> <20260918032038.2216471-9-den@valinux.co.jp> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Fri, 18 Sep 2026 03:24:46 +0000 Message-Id: <20260918032446.815351F00893@smtp.kernel.org> Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: > Commit f5cd8a929c82 ("PCI: dwc: Remove MSI/MSIX capability for Root Port > if iMSI-RX is used as MSI controller") hides the Root Port MSI/MSI-X > capabilities when iMSI-RX is the MSI controller, as it cannot receive > the Root Port's own MSIs. >=20 > Some platforms cannot deliver them with an external MSI controller > either. The DesignWare core signals Root Port interrupts (AER, PME, > bandwidth, hotplug) as sideband signals on its SII interface and only > turns them into MSI writes with the optional SII2MSI feature. Otherwise > it is up to the vendor wrapper. R-Car Gen4 (DWC 5.20a) appears to lack > SII2MSI, and its APP block merely latches the signals into status > registers wired to platform IRQs, so an MSI targeted at the GIC ITS is > never sent. >=20 > Add a no_rp_msi flag so glue drivers can request the same INTx fallback > regardless of the MSI controller in use. It is the counterpart of > 'keep_rp_msi_en' from commit 3a4e8302e72f ("PCI: imx6: Keep Root Port > MSI capability with iMSI-RX to work around hardware bug"), which keeps > precedence: that one is needed for endpoint MSIs to work at all, whereas > hiding the capability only moves the Root Port services to INTx. The > removal stays in dw_pcie_setup_rc(), which also runs after a Root Port > reset. >=20 > Signed-off-by: Koichiro Den Sashiko has reviewed this patch and found no issues. It looks great! --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20260918032038.2216= 471-1-den@valinux.co.jp?part=3D8