From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <SRS0=6E3r=WM=vger.kernel.org=linux-gpio-owner@kernel.org>
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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED,
	DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,
	MAILING_LIST_MULTI,SIGNED_OFF_BY,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 321DEC3A59D
	for <linux-gpio@archiver.kernel.org>; Fri, 16 Aug 2019 19:43:55 +0000 (UTC)
Received: from vger.kernel.org (vger.kernel.org [209.132.180.67])
	by mail.kernel.org (Postfix) with ESMTP id F33B0206C1
	for <linux-gpio@archiver.kernel.org>; Fri, 16 Aug 2019 19:43:54 +0000 (UTC)
Authentication-Results: mail.kernel.org;
	dkim=pass (2048-bit key) header.d=nvidia.com header.i=@nvidia.com header.b="H6QwagCn"
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
        id S1727628AbfHPTnx (ORCPT <rfc822;linux-gpio@archiver.kernel.org>);
        Fri, 16 Aug 2019 15:43:53 -0400
Received: from hqemgate16.nvidia.com ([216.228.121.65]:13233 "EHLO
        hqemgate16.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
        with ESMTP id S1727661AbfHPTm0 (ORCPT
        <rfc822;linux-gpio@vger.kernel.org>); Fri, 16 Aug 2019 15:42:26 -0400
Received: from hqpgpgate101.nvidia.com (Not Verified[216.228.121.13]) by hqemgate16.nvidia.com (using TLS: TLSv1.2, DES-CBC3-SHA)
        id <B5d5707230002>; Fri, 16 Aug 2019 12:42:27 -0700
Received: from hqmail.nvidia.com ([172.20.161.6])
  by hqpgpgate101.nvidia.com (PGP Universal service);
  Fri, 16 Aug 2019 12:42:24 -0700
X-PGP-Universal: processed;
        by hqpgpgate101.nvidia.com on Fri, 16 Aug 2019 12:42:24 -0700
Received: from HQMAIL110.nvidia.com (172.18.146.15) by HQMAIL104.nvidia.com
 (172.18.146.11) with Microsoft SMTP Server (TLS) id 15.0.1473.3; Fri, 16 Aug
 2019 19:42:23 +0000
Received: from HQMAIL101.nvidia.com (172.20.187.10) by hqmail110.nvidia.com
 (172.18.146.15) with Microsoft SMTP Server (TLS) id 15.0.1473.3; Fri, 16 Aug
 2019 19:42:23 +0000
Received: from hqnvemgw01.nvidia.com (172.20.150.20) by HQMAIL101.nvidia.com
 (172.20.187.10) with Microsoft SMTP Server (TLS) id 15.0.1473.3 via Frontend
 Transport; Fri, 16 Aug 2019 19:42:23 +0000
Received: from skomatineni-linux.nvidia.com (Not Verified[10.2.166.126]) by hqnvemgw01.nvidia.com with Trustwave SEG (v7,5,8,10121)
        id <B5d57071d0000>; Fri, 16 Aug 2019 12:42:23 -0700
From:   Sowjanya Komatineni <skomatineni@nvidia.com>
To:     <thierry.reding@gmail.com>, <jonathanh@nvidia.com>,
        <tglx@linutronix.de>, <jason@lakedaemon.net>,
        <marc.zyngier@arm.com>, <linus.walleij@linaro.org>,
        <stefan@agner.ch>, <mark.rutland@arm.com>
CC:     <pdeschrijver@nvidia.com>, <pgaikwad@nvidia.com>,
        <sboyd@kernel.org>, <linux-clk@vger.kernel.org>,
        <linux-gpio@vger.kernel.org>, <jckuo@nvidia.com>,
        <josephl@nvidia.com>, <talho@nvidia.com>, <skomatineni@nvidia.com>,
        <linux-tegra@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        <mperttunen@nvidia.com>, <spatra@nvidia.com>, <robh+dt@kernel.org>,
        <digetx@gmail.com>, <devicetree@vger.kernel.org>,
        <rjw@rjwysocki.net>, <viresh.kumar@linaro.org>,
        <linux-pm@vger.kernel.org>
Subject: [PATCH v9 05/22] clk: tegra: pll: Save and restore pll context
Date:   Fri, 16 Aug 2019 12:41:50 -0700
Message-ID: <1565984527-5272-6-git-send-email-skomatineni@nvidia.com>
X-Mailer: git-send-email 2.7.4
In-Reply-To: <1565984527-5272-1-git-send-email-skomatineni@nvidia.com>
References: <1565984527-5272-1-git-send-email-skomatineni@nvidia.com>
X-NVConfidentiality: public
MIME-Version: 1.0
Content-Type: text/plain
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nvidia.com; s=n1;
        t=1565984547; bh=cuX86Gbvu2GiH0TrxAcpwKRDIfjySVNpjUXIW6UATOE=;
        h=X-PGP-Universal:From:To:CC:Subject:Date:Message-ID:X-Mailer:
         In-Reply-To:References:X-NVConfidentiality:MIME-Version:
         Content-Type;
        b=H6QwagCnsCNMKbs5cfjCj4InXuQi9bP5kmm6r1goDxsGtWCDf9u7x/Ezy5O0J5Xcl
         ual3piCRW+uGtE6v9crAyzUpFJPBz8EcV9ujWW/Q9ZqX9fDZ1VtHU42IE/g1o6LVbo
         h6uJqiBeYCjv0PNJlHXUa/OpyHPBz46aPZ7Fql+yvMilpXJZn6u1MHAnYcd0tKsaQR
         m7hmOAVtdpDDT0Sh67A5wmNG4KQQZcKyWPgWX4IeO40Q7IDkISXp2p3GQeKFiG0XVP
         DZ0gR+8cJU5CbE84X4AiaSCjWP6dmLwFIJZWSfvCUCxK8UBZL0g2H6nPu2ybphhvm2
         5R5jgXoAanUAg==
Sender: linux-gpio-owner@vger.kernel.org
Precedence: bulk
List-ID: <linux-gpio.vger.kernel.org>
X-Mailing-List: linux-gpio@vger.kernel.org

This patch implements save and restore of PLL context.

During system suspend, core power goes off and looses the settings
of the Tegra CAR controller registers.

So during resume, pll context is restored based on cached rate
and state.

Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
---
 drivers/clk/tegra/clk-pll.c | 86 ++++++++++++++++++++++++++++-----------------
 1 file changed, 54 insertions(+), 32 deletions(-)

diff --git a/drivers/clk/tegra/clk-pll.c b/drivers/clk/tegra/clk-pll.c
index 1583f5fc992f..531c2b3d814e 100644
--- a/drivers/clk/tegra/clk-pll.c
+++ b/drivers/clk/tegra/clk-pll.c
@@ -1008,6 +1008,27 @@ static unsigned long clk_plle_recalc_rate(struct clk_hw *hw,
 	return rate;
 }
 
+static void tegra_clk_pll_restore_context(struct clk_hw *hw)
+{
+	struct tegra_clk_pll *pll = to_clk_pll(hw);
+	struct clk_hw *parent = clk_hw_get_parent(hw);
+	unsigned long parent_rate = clk_hw_get_rate(parent);
+	unsigned long rate = clk_hw_get_rate(hw);
+
+	if (clk_pll_is_enabled(hw))
+		return;
+
+	if (pll->params->set_defaults)
+		pll->params->set_defaults(pll);
+
+	clk_pll_set_rate(hw, rate, parent_rate);
+
+	if (!__clk_get_enable_count(hw->clk))
+		clk_pll_disable(hw);
+	else
+		clk_pll_enable(hw);
+}
+
 const struct clk_ops tegra_clk_pll_ops = {
 	.is_enabled = clk_pll_is_enabled,
 	.enable = clk_pll_enable,
@@ -1015,6 +1036,7 @@ const struct clk_ops tegra_clk_pll_ops = {
 	.recalc_rate = clk_pll_recalc_rate,
 	.round_rate = clk_pll_round_rate,
 	.set_rate = clk_pll_set_rate,
+	.restore_context = tegra_clk_pll_restore_context,
 };
 
 const struct clk_ops tegra_clk_plle_ops = {
@@ -1802,6 +1824,27 @@ static int clk_pllu_tegra114_enable(struct clk_hw *hw)
 
 	return ret;
 }
+
+static void _clk_plle_tegra_init_parent(struct tegra_clk_pll *pll)
+{
+	u32 val, val_aux;
+
+	/* ensure parent is set to pll_ref */
+	val = pll_readl_base(pll);
+	val_aux = pll_readl(pll->params->aux_reg, pll);
+
+	if (val & PLL_BASE_ENABLE) {
+		if ((val_aux & PLLE_AUX_PLLRE_SEL) ||
+		    (val_aux & PLLE_AUX_PLLP_SEL))
+			WARN(1, "pll_e enabled with unsupported parent %s\n",
+			     (val_aux & PLLE_AUX_PLLP_SEL) ? "pllp_out0" :
+			     "pll_re_vco");
+	} else {
+		val_aux &= ~(PLLE_AUX_PLLRE_SEL | PLLE_AUX_PLLP_SEL);
+		pll_writel(val_aux, pll->params->aux_reg, pll);
+		fence_udelay(1, pll->clk_base);
+	}
+}
 #endif
 
 static struct tegra_clk_pll *_tegra_init_pll(void __iomem *clk_base,
@@ -2214,27 +2257,12 @@ struct clk *tegra_clk_register_plle_tegra114(const char *name,
 {
 	struct tegra_clk_pll *pll;
 	struct clk *clk;
-	u32 val, val_aux;
 
 	pll = _tegra_init_pll(clk_base, NULL, pll_params, lock);
 	if (IS_ERR(pll))
 		return ERR_CAST(pll);
 
-	/* ensure parent is set to pll_re_vco */
-
-	val = pll_readl_base(pll);
-	val_aux = pll_readl(pll_params->aux_reg, pll);
-
-	if (val & PLL_BASE_ENABLE) {
-		if ((val_aux & PLLE_AUX_PLLRE_SEL) ||
-			(val_aux & PLLE_AUX_PLLP_SEL))
-			WARN(1, "pll_e enabled with unsupported parent %s\n",
-			  (val_aux & PLLE_AUX_PLLP_SEL) ? "pllp_out0" :
-					"pll_re_vco");
-	} else {
-		val_aux &= ~(PLLE_AUX_PLLRE_SEL | PLLE_AUX_PLLP_SEL);
-		pll_writel(val_aux, pll_params->aux_reg, pll);
-	}
+	_clk_plle_tegra_init_parent(pll);
 
 	clk = _tegra_clk_register_pll(pll, name, parent_name, flags,
 				      &tegra_clk_plle_tegra114_ops);
@@ -2276,6 +2304,7 @@ static const struct clk_ops tegra_clk_pllss_ops = {
 	.recalc_rate = clk_pll_recalc_rate,
 	.round_rate = clk_pll_ramp_round_rate,
 	.set_rate = clk_pllxc_set_rate,
+	.restore_context = tegra_clk_pll_restore_context,
 };
 
 struct clk *tegra_clk_register_pllss(const char *name, const char *parent_name,
@@ -2520,11 +2549,19 @@ static void clk_plle_tegra210_disable(struct clk_hw *hw)
 		spin_unlock_irqrestore(pll->lock, flags);
 }
 
+static void tegra_clk_plle_t210_restore_context(struct clk_hw *hw)
+{
+	struct tegra_clk_pll *pll = to_clk_pll(hw);
+
+	_clk_plle_tegra_init_parent(pll);
+}
+
 static const struct clk_ops tegra_clk_plle_tegra210_ops = {
 	.is_enabled =  clk_plle_tegra210_is_enabled,
 	.enable = clk_plle_tegra210_enable,
 	.disable = clk_plle_tegra210_disable,
 	.recalc_rate = clk_pll_recalc_rate,
+	.restore_context = tegra_clk_plle_t210_restore_context,
 };
 
 struct clk *tegra_clk_register_plle_tegra210(const char *name,
@@ -2535,27 +2572,12 @@ struct clk *tegra_clk_register_plle_tegra210(const char *name,
 {
 	struct tegra_clk_pll *pll;
 	struct clk *clk;
-	u32 val, val_aux;
 
 	pll = _tegra_init_pll(clk_base, NULL, pll_params, lock);
 	if (IS_ERR(pll))
 		return ERR_CAST(pll);
 
-	/* ensure parent is set to pll_re_vco */
-
-	val = pll_readl_base(pll);
-	val_aux = pll_readl(pll_params->aux_reg, pll);
-
-	if (val & PLLE_BASE_ENABLE) {
-		if ((val_aux & PLLE_AUX_PLLRE_SEL) ||
-			(val_aux & PLLE_AUX_PLLP_SEL))
-			WARN(1, "pll_e enabled with unsupported parent %s\n",
-			  (val_aux & PLLE_AUX_PLLP_SEL) ? "pllp_out0" :
-					"pll_re_vco");
-	} else {
-		val_aux &= ~(PLLE_AUX_PLLRE_SEL | PLLE_AUX_PLLP_SEL);
-		pll_writel(val_aux, pll_params->aux_reg, pll);
-	}
+	_clk_plle_tegra_init_parent(pll);
 
 	clk = _tegra_clk_register_pll(pll, name, parent_name, flags,
 				      &tegra_clk_plle_tegra210_ops);
-- 
2.7.4