From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-1098017-1521803715-2-4531783478425171321 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.25, ME_NOAUTH 0.01, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES en, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='CN', FromHeader='org', MailFrom='org' X-Spam-charsets: plain='UTF-8' X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: stable-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=arctest; t=1521803714; b=jmdYG2P1vB5RHl55bupkmIQTATgGp/jHinq7Y++nAF0AMnH LNY2krsqXnPTUlDtjOJb0hyzrr4T25rpWLajHh7FMXaWm0tGDtppX5yAXsDuQl4C glly2WvY7tN/lt1wV5xslCTm71nJQwxoMTpfXxpFWQOrwIQynuyumYwyNCLYulhp RIv0tUNYBK4eLduxc50xMZ6osPhFqOpgpwQLkQDA2lBdcJ9tQAut2c8sTuh11KGH gFrZ1ws7Mgn5FrO3KsGR2PYrgL1Ale5lHWC1Y9e/j3zYVPEEVFM3h6/DlzWDH/+F vJhF24mEgypyTYVi4SZipJK70DwSqA1zMbA/Hcg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=from:to:cc:subject:date:message-id :in-reply-to:references:mime-version:content-type:sender :list-id; s=arctest; t=1521803714; bh=MsYWKBl2xUwXUilwBEGrJxcjgI yolWsfw1MhEnPSx7E=; b=QJ7EUYpAoyFU0RUgM0Sm6qogUiRFtzrwZ747/4fFGb d4nae2vBqj79525i5L2a7bykgeGIumjdJyEQ6Vm2IStbyESZGMkogVyvOUGXoXCJ 2VQP4uaeSzS1odh84tHGIa80M2b7g+1EjrbRjC3Nn1tl6nPY5/b9ygTreBwKXfrJ jXq8ffYrCZq5QjBli9u/EMlsnGIap+BPZbidP9cZuDYf0KUFryKHx5IuTQn7Ij+M aFiqskC9N2J0y3Axr2vEgrJJPd2eWZD7j4AOmdGtWyTMLxUrFGuEA15ERsrywhkC ejlUFTVBAQpMhphbJlsTPjAjEfyWCjgJvcu51B+M3TBw== ARC-Authentication-Results: i=1; mx2.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=linuxfoundation.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=linuxfoundation.org header.result=pass header_is_org_domain=yes; x-vs=clean score=-100 state=0 Authentication-Results: mx2.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=linuxfoundation.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=linuxfoundation.org header.result=pass header_is_org_domain=yes; x-vs=clean score=-100 state=0 X-ME-VSCategory: clean Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932622AbeCWKKJ (ORCPT ); Fri, 23 Mar 2018 06:10:09 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:42396 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932375AbeCWKKH (ORCPT ); Fri, 23 Mar 2018 06:10:07 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Valentin Longchamp , Scott Wood , Sasha Levin Subject: [PATCH 4.9 105/177] soc/fsl/qe: round brg_freq to 1kHz granularity Date: Fri, 23 Mar 2018 10:53:53 +0100 Message-Id: <20180323094209.916492535@linuxfoundation.org> X-Mailer: git-send-email 2.16.2 In-Reply-To: <20180323094205.090519271@linuxfoundation.org> References: <20180323094205.090519271@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org X-Mailing-List: stable@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Valentin Longchamp [ Upstream commit 2ccf80b7566cc035d903dd0ac5d7ebd25c2c1060 ] Because of integer computation rounding in u-boot (that sets the QE brg-frequency DTS prop), the clk value is 99999999 Hz even though it is 100 MHz. When setting brg clks that are exact divisors of 100 MHz, this small differnce plays a role and can result in lower clks to be output (for instance 20 MHz - divide by 5 - results in 16.666 MHz - divide by 6). This patch fixes that by "forcing" the brg_clk to the nearest kHz when the difference is below 2 integer rounding errors (i.e. 4). Signed-off-by: Valentin Longchamp Signed-off-by: Scott Wood Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/soc/fsl/qe/qe.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) --- a/drivers/soc/fsl/qe/qe.c +++ b/drivers/soc/fsl/qe/qe.c @@ -163,11 +163,15 @@ EXPORT_SYMBOL(qe_issue_cmd); */ static unsigned int brg_clk = 0; +#define CLK_GRAN (1000) +#define CLK_GRAN_LIMIT (5) + unsigned int qe_get_brg_clk(void) { struct device_node *qe; int size; const u32 *prop; + unsigned int mod; if (brg_clk) return brg_clk; @@ -185,6 +189,15 @@ unsigned int qe_get_brg_clk(void) of_node_put(qe); + /* round this if near to a multiple of CLK_GRAN */ + mod = brg_clk % CLK_GRAN; + if (mod) { + if (mod < CLK_GRAN_LIMIT) + brg_clk -= mod; + else if (mod > (CLK_GRAN - CLK_GRAN_LIMIT)) + brg_clk += CLK_GRAN - mod; + } + return brg_clk; } EXPORT_SYMBOL(qe_get_brg_clk);