From patchwork Fri Dec 2 09:05:43 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "J, KEERTHY" X-Patchwork-Id: 9458063 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 8E49E60515 for ; Fri, 2 Dec 2016 09:06:48 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 88CAD28540 for ; Fri, 2 Dec 2016 09:06:48 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 7D8722854F; Fri, 2 Dec 2016 09:06:48 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E6F9528540 for ; Fri, 2 Dec 2016 09:06:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757947AbcLBJGP (ORCPT ); Fri, 2 Dec 2016 04:06:15 -0500 Received: from fllnx210.ext.ti.com ([198.47.19.17]:52483 "EHLO fllnx210.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756290AbcLBJGJ (ORCPT ); Fri, 2 Dec 2016 04:06:09 -0500 Received: from dflxv15.itg.ti.com ([128.247.5.124]) by fllnx210.ext.ti.com (8.15.1/8.15.1) with ESMTP id uB2966o4029661; Fri, 2 Dec 2016 03:06:06 -0600 Received: from DFLE73.ent.ti.com (dfle73.ent.ti.com [128.247.5.110]) by dflxv15.itg.ti.com (8.14.3/8.13.8) with ESMTP id uB2966mP006624; Fri, 2 Dec 2016 03:06:06 -0600 Received: from dflp32.itg.ti.com (10.64.6.15) by DFLE73.ent.ti.com (128.247.5.110) with Microsoft SMTP Server id 14.3.294.0; Fri, 2 Dec 2016 03:06:05 -0600 Received: from ula0393675.dhcp.ti.com (ileax41-snat.itg.ti.com [10.172.224.153]) by dflp32.itg.ti.com (8.14.3/8.13.8) with ESMTP id uB2960TC024162; Fri, 2 Dec 2016 03:06:02 -0600 From: Keerthy To: CC: , , , , , Subject: [PATCH] clk: ti: divider: Add the table parsing to get the best divider value Date: Fri, 2 Dec 2016 14:35:43 +0530 Message-ID: <1480669543-16197-1-git-send-email-j-keerthy@ti.com> X-Mailer: git-send-email 1.9.1 MIME-Version: 1.0 Sender: linux-omap-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-omap@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Currently the divider selection logic blindly divides the parent_rate by the clk rate and gives the divider value for the divider clocks which do not have the CLK_SET_RATE_PARENT flag set. Add the clk divider table parsing to get the closest divider available in the table provided via Device tree. The code is pretty much taken from: drivers/clk/clk-divider.c. and used here to fix up the best divider selection logic. Signed-off-by: Keerthy Reported-by: Richard Woodruff Acked-by: Tero Kristo --- drivers/clk/ti/divider.c | 31 ++++++++++++++++++++++++++++++- 1 file changed, 30 insertions(+), 1 deletion(-) diff --git a/drivers/clk/ti/divider.c b/drivers/clk/ti/divider.c index b4e5de1..6bb8778 100644 --- a/drivers/clk/ti/divider.c +++ b/drivers/clk/ti/divider.c @@ -140,6 +140,35 @@ static bool _is_valid_div(struct clk_divider *divider, unsigned int div) return true; } +static int _div_round_up(const struct clk_div_table *table, + unsigned long parent_rate, unsigned long rate) +{ + const struct clk_div_table *clkt; + int up = INT_MAX; + int div = DIV_ROUND_UP_ULL((u64)parent_rate, rate); + + for (clkt = table; clkt->div; clkt++) { + if (clkt->div == div) + return clkt->div; + else if (clkt->div < div) + continue; + + if ((clkt->div - div) < (up - div)) + up = clkt->div; + } + + return up; +} + +static int _div_round(const struct clk_div_table *table, + unsigned long parent_rate, unsigned long rate) +{ + if (!table) + return DIV_ROUND_UP(parent_rate, rate); + + return _div_round_up(table, parent_rate, rate); +} + static int ti_clk_divider_bestdiv(struct clk_hw *hw, unsigned long rate, unsigned long *best_parent_rate) { @@ -155,7 +184,7 @@ static int ti_clk_divider_bestdiv(struct clk_hw *hw, unsigned long rate, if (!(clk_hw_get_flags(hw) & CLK_SET_RATE_PARENT)) { parent_rate = *best_parent_rate; - bestdiv = DIV_ROUND_UP(parent_rate, rate); + bestdiv = _div_round(divider->table, parent_rate, rate); bestdiv = bestdiv == 0 ? 1 : bestdiv; bestdiv = bestdiv > maxdiv ? maxdiv : bestdiv; return bestdiv;