From patchwork Fri Nov 4 06:42:56 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: James Liao X-Patchwork-Id: 9411989 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 8F91160585 for ; Fri, 4 Nov 2016 06:45:15 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 803792AB36 for ; Fri, 4 Nov 2016 06:45:15 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 7226F2AB7C; Fri, 4 Nov 2016 06:45:15 +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=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 088CF2AB36 for ; Fri, 4 Nov 2016 06:45:15 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.85_2 #1 (Red Hat Linux)) id 1c2YDr-0008VC-EV; Fri, 04 Nov 2016 06:43:31 +0000 Received: from [210.61.82.183] (helo=mailgw01.mediatek.com) by bombadil.infradead.org with esmtp (Exim 4.85_2 #1 (Red Hat Linux)) id 1c2YDm-0008T7-I2; Fri, 04 Nov 2016 06:43:27 +0000 Received: from mtkhts07.mediatek.inc [(172.21.101.69)] by mailgw01.mediatek.com (envelope-from ) (mhqrelay.mediatek.com ESMTP with TLS) with ESMTP id 534932438; Fri, 04 Nov 2016 14:43:00 +0800 Received: from mtksdtcf04.mediatek.inc (10.21.12.144) by mtkhts07.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 14.3.266.1; Fri, 4 Nov 2016 14:42:59 +0800 From: James Liao To: Matthias Brugger , Mike Turquette , Stephen Boyd Subject: [PATCH v3] clk: mediatek: Allow changing PLL rate when it is off Date: Fri, 4 Nov 2016 14:42:56 +0800 Message-ID: <1478241776-50687-1-git-send-email-jamesjj.liao@mediatek.com> X-Mailer: git-send-email 1.9.1 MIME-Version: 1.0 X-MTK: N X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20161103_234326_769300_FB0977E4 X-CRM114-Status: GOOD ( 12.40 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: devicetree@vger.kernel.org, srv_heupstream@mediatek.com, James Liao , linux-kernel@vger.kernel.org, Daniel Kurtz , linux-mediatek@lists.infradead.org, Sascha Hauer , linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP Some modules may need to change its clock rate before turn on it. So changing PLL's rate when it is off should be allowed. This patch removes PLL enabled check before set rate, so that PLLs can set new frequency even if they are off. On MT8173 for example, ARMPLL's enable bit can be controlled by other HW. That means ARMPLL may be turned on even if we (CPU / SW) set ARMPLL's enable bit as 0. In this case, SW may want and can still change ARMPLL's rate by changing its pcw and postdiv settings. But without this patch, new pcw setting will not be applied because its enable bit is 0. Signed-off-by: James Liao Acked-by: Michael Turquette --- Please refer to previous comments in [1] and [2]. changes since v2: - Rebase to v4.9-rc1. changes since v1: - Add more explanation in commit messages. [1] https://patchwork.kernel.org/patch/7983221/ [2] https://patchwork.kernel.org/patch/7998891/ drivers/clk/mediatek/clk-pll.c | 9 ++------- 1 file changed, 2 insertions(+), 7 deletions(-) diff --git a/drivers/clk/mediatek/clk-pll.c b/drivers/clk/mediatek/clk-pll.c index 0c2deac..80f57b4 100644 --- a/drivers/clk/mediatek/clk-pll.c +++ b/drivers/clk/mediatek/clk-pll.c @@ -91,9 +91,6 @@ static void mtk_pll_set_rate_regs(struct mtk_clk_pll *pll, u32 pcw, int postdiv) { u32 con1, val; - int pll_en; - - pll_en = readl(pll->base_addr + REG_CON0) & CON0_BASE_EN; /* set postdiv */ val = readl(pll->pd_addr); @@ -114,15 +111,13 @@ static void mtk_pll_set_rate_regs(struct mtk_clk_pll *pll, u32 pcw, con1 = readl(pll->base_addr + REG_CON1); - if (pll_en) - con1 |= CON0_PCW_CHG; + con1 |= CON0_PCW_CHG; writel(con1, pll->base_addr + REG_CON1); if (pll->tuner_addr) writel(con1 + 1, pll->tuner_addr); - if (pll_en) - udelay(20); + udelay(20); } /*