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 2F3EB3451C1; Thu, 14 May 2026 18:22:39 +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=1778782960; cv=none; b=Q8mVIwjkvaXcWaToYxKudXdzWirx9PyKg7vO6kritr+gGQy8n2IFDL0qVZsfxMLoQ83RQIQXTuc7fFZc04fgZQlLGP0SjB5YkO7rltfecyCAj/Lyp20+2GBu0Smif5vunAZdAt12hZCPqkBJofBhkNG8tssoFHkE0nCrJOc2MxI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778782960; c=relaxed/simple; bh=tcNcx48a+go1+PIXbPVx+bqSAKU5IIdX2EligEhqik8=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=jCCNTxl9QAhv9cnlmVfxdhMyYEMKfxia29WBV6iBpEUpoAXyAwt6L1Z5WGoREnTq8oNBHlXyJV53zy+4rC7q5MlvmmM2U7Pvt/xdlPiEGIcfZETipEEawfXtuNSjUlME9kgVOl0+8IF+SQW07K5vl4vW/yWV4zMlCxrPKtOb0V0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=a3YNDsyz; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="a3YNDsyz" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7D81DC2BCB3; Thu, 14 May 2026 18:22:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1778782959; bh=tcNcx48a+go1+PIXbPVx+bqSAKU5IIdX2EligEhqik8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=a3YNDsyzai9dvNt6VZBDL6ERsW+oYVA2SykU/Obr7s07OgADYxAhobMPBDxXiK9Kn iaHArLA19pu2f3di2hQZqXd2e1RWdCXA3QcZ88NW3ZbVhhEHl/fC7sMj7o2BlN6BmJ TMUxOs1RcqEspBfQe+k0J8arhd1Z9I1ROQ44uXxqNNizC66LkvfDPGRYbKchEhnE0Z BGaYw+akOZZ7t4xNb+cHVMaLCA51K3B6ERnIckfj6ZXwvh7gg4L9l5MrwvZBe0b81k 8SOjRmi5nHbWQGGW8K4rB3hYpz2KGFY8Pb3Pkfbppk6mzcIlgv6lQMWTIBA9raABrj 6bKc7sa1QPwCg== Date: Thu, 14 May 2026 19:22:36 +0100 From: Conor Dooley To: Caleb James DeLisle Cc: sashiko-reviews@lists.linux.dev, devicetree@vger.kernel.org, conor+dt@kernel.org, krzk+dt@kernel.org, robh@kernel.org Subject: Re: [PATCH v2 1/5] dt-bindings: timer: econet: Update EN751627 for multi-IRQ Message-ID: <20260514-abiding-entertain-cd2aab06bef5@spud> References: <20260514000601.3430262-2-cjd@cjdns.fr> <20260514114243.126F4C2BCB3@smtp.kernel.org> <23568f49-4b58-4acd-85fa-7eba5e99b46c@cjdns.fr> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="U3nnOgtn/eu2wwWq" Content-Disposition: inline In-Reply-To: <23568f49-4b58-4acd-85fa-7eba5e99b46c@cjdns.fr> --U3nnOgtn/eu2wwWq Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, May 14, 2026 at 05:22:05PM +0200, Caleb James DeLisle wrote: > > > @@ -52,21 +52,31 @@ allOf: > > > items: > > > - description: VPE timers 0 and 1 > > > - description: VPE timers 2 and 3 > > > + interrupts: > > > + description: An interrupt for each timer (one per VPE) > > > + minItems: 4 > > Could this include an items list detailing the specific purpose of each > > of the four interrupts? Defining an items array for each interrupt (suc= h as > > Timer for VPE 0, VPE 1, etc.) would help ensure clarity for driver deve= lopers > > and enforce a consistent definition order. > IMO should be self-evident. Ye, I think this is okay. Perhaps you could make it an items list if you want though. > >=20 > > [ ... ] > > > examples: > > > - | > > > + #include > > > timer@1fbf0400 { > > > compatible =3D "econet,en751627-timer", "econet,en751221-ti= mer"; > > Is it safe to retain econet,en751221-timer as a fallback compatible str= ing? > >=20 > > Device Tree fallback strings declare that an older OS can safely operat= e the > > hardware using the fallback driver. Since econet,en751627-timer uses fo= ur > > individual shared IRQs while econet,en751221-timer strictly uses a sing= le > > percpu IRQ, they appear to have fundamentally incompatible interrupt > > topologies. > >=20 > > If an older kernel boots using the fallback, the legacy > > timer-econet-en751221 driver will attempt to map the first shared IRQ a= s a > > percpu IRQ via request_percpu_irq(). This will fail with -EINVAL, causi= ng > > the timer driver to fail to initialize and potentially leading to a boot > > failure or system hang. > >=20 > > Should econet,en751627-timer be defined as a standalone compatible stri= ng > > without the econet,en751221-timer fallback? > I find this argument compelling so I'll switch. And ye, this is a good point that it made. > >=20 > > > reg =3D <0x1fbf0400 0x100>, <0x1fbe0000 0x100>; > > > interrupt-parent =3D <&intc>; > > > - interrupts =3D <30>; > > > + interrupts =3D , > > > + , > > > + , > > > + ; > > > clocks =3D <&hpt_clock>; > > > }; --U3nnOgtn/eu2wwWq Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQRh246EGq/8RLhDjO14tDGHoIJi0gUCagYS7AAKCRB4tDGHoIJi 0tmOAQC/dD5AgiYmPrze2oXBe2h36kSTdYvxZrJXj8IcC3moKAD7BfI60QSdELli +gBfkkaGm+igCABXL8s8C8+kOQoTnwQ= =ZGnf -----END PGP SIGNATURE----- --U3nnOgtn/eu2wwWq--