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 F09DACA9ECA for ; Sun, 11 Oct 2026 09:45:32 +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: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=hzklMIa+OcS580+DlUByvFd6dTQm7xRfECj9JDqQ+Ic=; b=PiEC6UxbnAyBcQlOYR7dIgJYp8 MWt+AYogy/ahg4kWcW3LElUXFGY9wKgdm5tXHAXQEP48zGZoKuT5hry3IGZD/3EUW7JACvAvPtlPg gJ8LiNi0jvOGsg5yZECSlW1cmKWeb3HbyrdAU3J3uwiFUfh/KEwjbGiQoTWb1/6Am3G6s2ZZF28Nt CkRTnD001CUI4W56HKtvsdwTgJNL0zvWV9uEDpL+NKtYXfuh0AKguwk7PylVJW+xtFa30jF5m1aHq 3gV865Lvq/zt7dZQ9hV6KJyuc977lDJiUXk+Etgu2Unk5lhrLOyXIQxCIqUNjn2sjXAdVcQyl6kIn G3Me5wPw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1xFq7N-00000008u5b-3ZlK; Sun, 11 Oct 2026 09:45:21 +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 1xFq7K-00000008u5B-0Uzp for linux-arm-kernel@lists.infradead.org; Sun, 11 Oct 2026 09:45:19 +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 8CB151682; Sun, 11 Oct 2026 02:45:10 -0700 (PDT) Received: from [10.57.13.91] (unknown [10.57.13.91]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 60FE03F882; Sun, 11 Oct 2026 02:45:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1791711913; bh=phYLsYaGezB/4VFRSxSZQZLhUrUxyt689g+K6n1e57g=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=TSZD1LhJJBKLyR8FUnRN2F3Zi766+Qsh2PiIOXHCAXkm0XYuD3L5XUp9RTPWVhg0L na1EvLuX5igyKGppH7bz7pzHtngbHMAuDoP5MDrMdf/vDi/Wg65mpfn/71+JcMN3C1 q8zvMSTP6/FdQGvxrMTZykCZ2L3JQGCf4k5IPqrQ= Message-ID: Date: Sun, 11 Oct 2026 10:45:10 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] firmware: smccc: Pass only the required device probe arguments Content-Language: en-GB To: "Aneesh Kumar K.V (Arm)" , linux-arm-kernel@lists.infradead.org Cc: Catalin Marinas , Lorenzo Pieralisi , Mark Rutland , Sudeep Holla , Will Deacon , Steven Price , Andre Przywara , Russell King , kernel test robot References: <20261010100249.643327-1-aneesh.kumar@kernel.org> From: Suzuki K Poulose In-Reply-To: <20261010100249.643327-1-aneesh.kumar@kernel.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20261011_024518_289905_9447E013 X-CRM114-Status: GOOD ( 16.58 ) 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 Hi Aneesh On 10/10/2026 11:02, Aneesh Kumar K.V (Arm) wrote: > The device probe passes zeroes for all seven argument registers to > arm_smccc_1_1_invoke(). On ARM32 Thumb-2, this binds an input to r7 and > GCC 8.5 reports "r7 cannot be used in asm here". > > The current smccc_devices entries need at most one argument after the > function ID: TRNG_VERSION has none and RSI_ABI_VERSION takes a requested > version. Pass zero for that argument and omit the unused arguments, > avoiding the r7 constraint. Check argument requirements when adding new > probe functions to smccc_devices. Is it safer to use x1-x3 to 0 as they could be the results that we get back from SMCCC v1.0 onwards ? Suzuki > > Cc: Catalin Marinas > Cc: Lorenzo Pieralisi > Cc: Mark Rutland > Cc: Sudeep Holla > Cc: Will Deacon > Cc: Steven Price > Cc: Suzuki K Poulose > Cc: Andre Przywara > Cc: Russell King > Fixes: d8263a131bb0 ("firmware: hwrng: arm_smccc_trng: Register as an SMCCC device") > Reported-by: kernel test robot > Closes: https://lore.kernel.org/oe-kbuild-all/202610070641.B8hxBJcf-lkp@intel.com/ > Signed-off-by: Aneesh Kumar K.V (Arm) > --- > drivers/firmware/smccc/smccc.c | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-) > > diff --git a/drivers/firmware/smccc/smccc.c b/drivers/firmware/smccc/smccc.c > index 07b864ff079d..377d2cda2b6e 100644 > --- a/drivers/firmware/smccc/smccc.c > +++ b/drivers/firmware/smccc/smccc.c > @@ -122,8 +122,7 @@ static bool __init smccc_probe_smccc_device(const struct smccc_device_info *smcc > if (IS_ENABLED(CONFIG_ARM) && ARM_SMCCC_IS_64(smccc_dev->func_id)) > return false; > > - arm_smccc_1_1_invoke(smccc_dev->func_id, > - 0, 0, 0, 0, 0, 0, 0, &res); > + arm_smccc_1_1_invoke(smccc_dev->func_id, 0, &res); > ret = res.a0; > > if (ret == SMCCC_RET_NOT_SUPPORTED)