From patchwork Mon Jul 22 04:01:18 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zeng Heng X-Patchwork-Id: 13738240 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 E2A9EC3DA5D for ; Mon, 22 Jul 2024 04:06:38 +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-Type: Content-Transfer-Encoding:MIME-Version:References:In-Reply-To:Message-ID:Date :Subject:CC:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=brU47bW0+7nNUJ0E/xqNnW8xrqFS7bTUYdQSxvuDvkQ=; b=W/yyPcTjBrsUJgJTZz2kFAb5XK 5pEfVFqmFT63HQny6YJ0gEbeEQwnpVYh+9T8E/f4Q6Xr/+IiFrO5JWn41Oeu9klddxqamSjzwDl9y 5K3PA1PbDJYvrnR5dc6jrm6K9GVRscKnlnE8S5xk/0CXmQRU9n+4uDZbLZvDmliugnKFXnceZON8N ic88hy7bSiOIND1PrjrYKFtgtC1MtQhrHtl6IYy4ZIQA7sewiVDIkStF4nk87ZIS2CJrocjbZhQ1M mL5RQZoCwcnQCzq+0vwl+fI9JvOOurf3kIcg8RGGFE2Ze0KlGCT7pNbDbVapDcmL6arFIMfIam/2o 517AZR/A==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sVkJf-00000008H02-1kWf; Mon, 22 Jul 2024 04:06:27 +0000 Received: from szxga08-in.huawei.com ([45.249.212.255]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1sVkIx-00000008GlK-2uyE for linux-arm-kernel@lists.infradead.org; Mon, 22 Jul 2024 04:05:46 +0000 Received: from mail.maildlp.com (unknown [172.19.163.48]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4WS64v3qSgz1JDRb; Mon, 22 Jul 2024 12:00:31 +0800 (CST) Received: from kwepemf100008.china.huawei.com (unknown [7.202.181.222]) by mail.maildlp.com (Postfix) with ESMTPS id 807B8180064; Mon, 22 Jul 2024 12:05:29 +0800 (CST) Received: from huawei.com (10.175.103.91) by kwepemf100008.china.huawei.com (7.202.181.222) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Mon, 22 Jul 2024 12:05:28 +0800 From: Zeng Heng To: , , , CC: , , , Subject: [PATCH mpam/v6.10-rc1 RFC 1/4] arm_mpam: Correct MBA granularity calculation Date: Mon, 22 Jul 2024 12:01:18 +0800 Message-ID: <20240722040121.515021-2-zengheng4@huawei.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20240722040121.515021-1-zengheng4@huawei.com> References: <20240722040121.515021-1-zengheng4@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.103.91] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To kwepemf100008.china.huawei.com (7.202.181.222) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240721_210543_920566_19EE0ED9 X-CRM114-Status: GOOD ( 10.89 ) 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 Correct MBA granularity calculation function. As said in the comments, "bwa_wd is the number of bits implemented in the 0.xxx fixed point fraction". Fixes: 867471fefd5c ("SPLIT untested: arm_mpam: resctrl: Add support for MB resource") Signed-off-by: Zeng Heng --- drivers/platform/arm64/mpam/mpam_resctrl.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/platform/arm64/mpam/mpam_resctrl.c b/drivers/platform/arm64/mpam/mpam_resctrl.c index 2fa732a42d4f..a217f2e1f350 100644 --- a/drivers/platform/arm64/mpam/mpam_resctrl.c +++ b/drivers/platform/arm64/mpam/mpam_resctrl.c @@ -523,7 +523,7 @@ static u32 get_mba_granularity(struct mpam_props *cprops) * bwa_wd is the number of bits implemented in the 0.xxx * fixed point fraction. 1 bit is 50%, 2 is 25% etc. */ - return MAX_MBA_BW / (cprops->bwa_wd + 1); + return MAX_MBA_BW / (1 << cprops->bwa_wd); } return 0;