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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (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 9246AEDF148 for ; Fri, 13 Feb 2026 10:59:56 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id F3DD010E7D0; Fri, 13 Feb 2026 10:59:55 +0000 (UTC) Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by gabe.freedesktop.org (Postfix) with ESMTP id 637B910E7D0 for ; Fri, 13 Feb 2026 10:59:55 +0000 (UTC) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id B1708339 for ; Fri, 13 Feb 2026 02:59:48 -0800 (PST) Received: from [192.168.0.1] (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id CE3523F73F for ; Fri, 13 Feb 2026 02:59:54 -0800 (PST) Date: Fri, 13 Feb 2026 10:57:49 +0000 From: Liviu Dudau To: Mark Brown Cc: Onur =?utf-8?B?w5Z6a2Fu?= , daniel.almeida@collabora.com, aliceryhl@google.com, dakr@kernel.org, airlied@gmail.com, simona@ffwll.ch, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, lgirdwood@gmail.com, ojeda@kernel.org, rust-for-linux@vger.kernel.org Subject: Re: [PATCH v2 1/1] drm/tyr: make SRAM supply optional like panthor Message-ID: References: <20260212100538.170445-1-work@onurozkan.dev> <20260212100538.170445-2-work@onurozkan.dev> <4b00826f-52b1-48a1-b6b5-70ee62f7c014@sirena.org.uk> <20260212151644.4c179594@nimda> <6704ddce-e0bb-4b50-b81a-a098816f3ba3@sirena.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <6704ddce-e0bb-4b50-b81a-a098816f3ba3@sirena.org.uk> X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On Thu, Feb 12, 2026 at 12:21:07PM +0000, Mark Brown wrote: > On Thu, Feb 12, 2026 at 03:16:44PM +0300, Onur Özkan wrote: > > Mark Brown wrote: > > > On Thu, Feb 12, 2026 at 01:05:38PM +0300, Onur Özkan wrote: > > > > > Panthor handles SRAM as optional and tolerates missing sram-supply. > > > > Does the RAM really work without power? > > > If the platform has no separate sram-supply (meaning that rail is > > coupled to mali), RAM should still be powered and work fine. Panthor > > already relies on this model by treating sram-supply as optional and > > as far as I can see there are no RAM issues on Panthor. > > The panthor driver is buggy here and should be fixed, the driver should > treat the supply as mandatory and let the system integration work out > how it's actually made available. Please note that the sram supply is mandatory in all compatibles except for the "mt8196-mali". This was to work around the fact that MTK has decided to control some supplies via another method and not give Panthor control over those. We should fix Panthor to check that we only treat the sram supply as optional for "mt8196-mali", but that doesn't alleviate Tyr's need to support optional regulators. Best regards, Liviu > > Trying to open code this just breaks the error handling. -- ==================== | I would like to | | fix the world, | | but they're not | | giving me the | \ source code! / --------------- ¯\_(ツ)_/¯