From patchwork Wed Dec 2 18:06:07 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sakari Ailus X-Patchwork-Id: 336317 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 557FAC71156 for ; Wed, 2 Dec 2020 18:11:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 082AD221FC for ; Wed, 2 Dec 2020 18:11:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728945AbgLBSLY (ORCPT ); Wed, 2 Dec 2020 13:11:24 -0500 Received: from retiisi.eu ([95.216.213.190]:33484 "EHLO hillosipuli.retiisi.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726283AbgLBSLY (ORCPT ); Wed, 2 Dec 2020 13:11:24 -0500 Received: from lanttu.localdomain (lanttu-e.localdomain [192.168.1.64]) by hillosipuli.retiisi.eu (Postfix) with ESMTP id 2811E634C8C; Wed, 2 Dec 2020 20:08:31 +0200 (EET) From: Sakari Ailus To: linux-media@vger.kernel.org Cc: mchehab@kernel.org Subject: [PATCH 04/38] ccs-pll: End search if there are no better values available Date: Wed, 2 Dec 2020 20:06:07 +0200 Message-Id: <20201202180641.17401-5-sakari.ailus@linux.intel.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20201202180641.17401-1-sakari.ailus@linux.intel.com> References: <20201202180641.17401-1-sakari.ailus@linux.intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org The VT divisor search can be ended if we've already found the value that corresponds exactly the total divisor, as there are no better (lower) values available. Signed-off-by: Sakari Ailus --- drivers/media/i2c/ccs-pll.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/media/i2c/ccs-pll.c b/drivers/media/i2c/ccs-pll.c index ea0f84fc8a90..22e29127804a 100644 --- a/drivers/media/i2c/ccs-pll.c +++ b/drivers/media/i2c/ccs-pll.c @@ -352,6 +352,7 @@ __ccs_pll_calculate(struct device *dev, const struct ccs_pll_limits *lim, sys_div <= max_sys_div; sys_div += 2 - (sys_div & 1)) { uint16_t pix_div = DIV_ROUND_UP(vt_div, sys_div); + uint16_t rounded_div; if (pix_div < lim->vt_bk.min_pix_clk_div || pix_div > lim->vt_bk.max_pix_clk_div) { @@ -363,10 +364,15 @@ __ccs_pll_calculate(struct device *dev, const struct ccs_pll_limits *lim, continue; } + rounded_div = roundup(vt_div, best_pix_div); + /* Check if this one is better. */ - if (pix_div * sys_div - <= roundup(vt_div, best_pix_div)) + if (pix_div * sys_div <= rounded_div) best_pix_div = pix_div; + + /* Bail out if we've already found the best value. */ + if (vt_div == rounded_div) + break; } if (best_pix_div < INT_MAX >> 1) break;