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 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_NONE,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 D6DC9C41538 for ; Thu, 1 Apr 2021 17:42:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5AA2B613CA for ; Thu, 1 Apr 2021 17:42:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234678AbhDARmS (ORCPT ); Thu, 1 Apr 2021 13:42:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57160 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234673AbhDARjG (ORCPT ); Thu, 1 Apr 2021 13:39:06 -0400 Received: from baptiste.telenet-ops.be (baptiste.telenet-ops.be [IPv6:2a02:1800:120:4::f00:13]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 91AA7C05BD29 for ; Thu, 1 Apr 2021 06:01:43 -0700 (PDT) Received: from ramsan.of.borg ([IPv6:2a02:1810:ac12:ed20:7c3c:adbc:7a1a:b85f]) by baptiste.telenet-ops.be with bizsmtp id nR1h240034A7w6i01R1haJ; Thu, 01 Apr 2021 15:01:41 +0200 Received: from rox.of.borg ([192.168.97.57]) by ramsan.of.borg with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1lRwxA-00CBkG-La; Thu, 01 Apr 2021 15:01:40 +0200 Received: from geert by rox.of.borg with local (Exim 4.93) (envelope-from ) id 1lRwx9-003mtQ-MW; Thu, 01 Apr 2021 15:01:39 +0200 From: Geert Uytterhoeven To: Michael Turquette , Stephen Boyd Cc: linux-renesas-soc@vger.kernel.org, linux-clk@vger.kernel.org, Geert Uytterhoeven Subject: [PATCH 4/5] clk: renesas: div6: Consider all parents for requested rate Date: Thu, 1 Apr 2021 15:01:37 +0200 Message-Id: <60e639692b462f99e0b6ab868c3675b3d97dbdb0.1617281699.git.geert+renesas@glider.be> X-Mailer: git-send-email 2.25.1 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-clk@vger.kernel.org Currently the .determine_rate() callback considers only the current parent clock, limiting the range of achievable clock rates on DIV6 clocks with multiple parents, as found on SH/R-Mobile SoCs. Extend the callback to consider all available parent clocks. Signed-off-by: Geert Uytterhoeven --- drivers/clk/renesas/clk-div6.c | 35 +++++++++++++++++++++++++++++++--- 1 file changed, 32 insertions(+), 3 deletions(-) diff --git a/drivers/clk/renesas/clk-div6.c b/drivers/clk/renesas/clk-div6.c index 3af65ef5690e3d84..a9ac2a83c1d0daa0 100644 --- a/drivers/clk/renesas/clk-div6.c +++ b/drivers/clk/renesas/clk-div6.c @@ -103,10 +103,39 @@ static unsigned int cpg_div6_clock_calc_div(unsigned long rate, static int cpg_div6_clock_determine_rate(struct clk_hw *hw, struct clk_rate_request *req) { - unsigned int div = cpg_div6_clock_calc_div(req->rate, - req->best_parent_rate); + unsigned long prate, calc_rate, diff, best_rate, best_prate; + unsigned int num_parents = clk_hw_get_num_parents(hw); + struct clk_hw *parent, *best_parent = NULL; + unsigned long min_diff = ULONG_MAX; + unsigned int i, div; + + for (i = 0; i < num_parents; i++) { + parent = clk_hw_get_parent_by_index(hw, i); + if (!parent) + continue; + + prate = clk_hw_get_rate(parent); + if (!prate) + continue; + + div = cpg_div6_clock_calc_div(req->rate, prate); + calc_rate = prate / div; + diff = calc_rate > req->rate ? calc_rate - req->rate + : req->rate - calc_rate; + if (diff < min_diff) { + best_rate = calc_rate; + best_parent = parent; + best_prate = prate; + min_diff = diff; + } + } + + if (!best_parent) + return -EINVAL; - req->rate = req->best_parent_rate / div; + req->best_parent_rate = best_prate; + req->best_parent_hw = best_parent; + req->rate = best_rate; return 0; } -- 2.25.1