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 B3668C43458 for ; Fri, 10 Jul 2026 14:46:19 +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:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=7T7V+nGPFbAzwPE9rpNbudYellrw6IUQBG3148Jhmlw=; b=AKgeQycnS8hXTZTyO0X1IN3jh4 ZlSwCxntElpP02OjVJQANa5KwzlwxKTUBUWQrXLE9rkJ9piKsOg5+BAod4xhwe54AWAtIgQShCZI1 yuUns3cWFVFpbfC2K2Tz3TD5R36m+H3fkYys0/aOG2yENMbz+faa+KWCbBlE+f8wVutObzqDzWNN1 vahU1FBEP+YO7U2JXIXRkJyCg+txIUfC6hitdIHFqXAPnzkAz8shmbRSVl+trV3Olr+oluJVmch76 y3QWGs72oX7caOTha+9XrH5DYcllcXKZjNnXeMAefUeFyAUF+OK6ILWr1NIsqNlXhptXw6Z5WwCIA toEWdYuA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wiCUW-0000000571U-1vAq; Fri, 10 Jul 2026 14:46:12 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wiCUU-000000056yn-00qF for linux-arm-kernel@lists.infradead.org; Fri, 10 Jul 2026 14:46:11 +0000 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 078B02308; Fri, 10 Jul 2026 07:46:05 -0700 (PDT) Received: from e142021.munich.arm.com (e142021.arm.com [10.41.150.148]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 5DA013F7B4; Fri, 10 Jul 2026 07:46:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1783694769; bh=zG916CSOag+6bdGmf8ocN9C8ja+Ns+Zo3Yu0tdFYbbc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fLekdet2zS/dSBydNcU2ITDWBc96c7Za8WFrZEIw8ghtBdrGBBJFwKo1ceBbyEK4Q GLasTVIQlNlq4UF3ReWh+DjvVAvo7sEiflr2pORm7v81V/gsTtPs0LL1JjmXM6U1Cn IneqeWuqA1/bSqCVVrSaPddGwyJq21hMbKY5XMgk= From: Andre Przywara To: Lorenzo Pieralisi , Hanjun Guo , Sudeep Holla , Catalin Marinas , Will Deacon , "Rafael J . Wysocki" , Len Brown , James Morse , Ben Horgan , Reinette Chatre , Fenghua Yu Cc: Jonathan Cameron , Srivathsa L Rao , Ganapatrao Kulkarni , Trilok Soni , Srinivas Ramana , Niyas Sait , linux-acpi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH v3 09/16] arm_mpam: let low level MSC write accessors return an error Date: Fri, 10 Jul 2026 16:45:13 +0200 Message-ID: <20260710144520.917375-10-andre.przywara@arm.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260710144520.917375-1-andre.przywara@arm.com> References: <20260710144520.917375-1-andre.przywara@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260710_074610_119772_0D822E7C X-CRM114-Status: GOOD ( 11.43 ) 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 The upcoming MPAM-Fb support does not use MMIO primitives to access an MSC, but employs a shared-memory/doorbell based firmware protocol. Its complexity means that is must be able to handle errors, whereas we always assume an MSC access succeeds today. Change the __mpam_write_reg() low level accessor function to return an error code. At the moment this is always 0, but this will change with alternative MSC access methods. Also change some low level wrappers to propagate the error. Signed-off-by: Andre Przywara --- drivers/resctrl/mpam_devices.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/drivers/resctrl/mpam_devices.c b/drivers/resctrl/mpam_devices.c index b2ecaba29fcc..f1e40ce24f5a 100644 --- a/drivers/resctrl/mpam_devices.c +++ b/drivers/resctrl/mpam_devices.c @@ -195,18 +195,20 @@ static inline int _mpam_read_partsel_reg(struct mpam_msc *msc, u16 reg, #define mpam_read_partsel_reg(msc, reg, res) _mpam_read_partsel_reg(msc, MPAMF_##reg, res) -static void __mpam_write_reg(struct mpam_msc *msc, u16 reg, u32 val) +static int __mpam_write_reg(struct mpam_msc *msc, u16 reg, u32 val) { WARN_ON_ONCE(reg + sizeof(u32) > msc->mapped_hwpage_sz); WARN_ON_ONCE(!cpumask_test_cpu(smp_processor_id(), &msc->accessibility)); writel_relaxed(val, msc->mapped_hwpage + reg); + + return 0; } -static inline void _mpam_write_partsel_reg(struct mpam_msc *msc, u16 reg, u32 val) +static inline int _mpam_write_partsel_reg(struct mpam_msc *msc, u16 reg, u32 val) { lockdep_assert_held_once(&msc->part_sel_lock); - __mpam_write_reg(msc, reg, val); + return __mpam_write_reg(msc, reg, val); } #define mpam_write_partsel_reg(msc, reg, val) _mpam_write_partsel_reg(msc, MPAMCFG_##reg, val) @@ -220,10 +222,10 @@ static inline int _mpam_read_monsel_reg(struct mpam_msc *msc, u16 reg, #define mpam_read_monsel_reg(msc, reg, res) _mpam_read_monsel_reg(msc, MSMON_##reg, res) -static inline void _mpam_write_monsel_reg(struct mpam_msc *msc, u16 reg, u32 val) +static inline int _mpam_write_monsel_reg(struct mpam_msc *msc, u16 reg, u32 val) { mpam_mon_sel_lock_held(msc); - __mpam_write_reg(msc, reg, val); + return __mpam_write_reg(msc, reg, val); } #define mpam_write_monsel_reg(msc, reg, val) _mpam_write_monsel_reg(msc, MSMON_##reg, val) -- 2.43.0