From patchwork Thu Dec 17 18:06:14 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Osipenko X-Patchwork-Id: 345054 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=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 61D42C2BBCF for ; Thu, 17 Dec 2020 18:13:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2ED302388E for ; Thu, 17 Dec 2020 18:13:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730271AbgLQSMa (ORCPT ); Thu, 17 Dec 2020 13:12:30 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41996 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730359AbgLQSI5 (ORCPT ); Thu, 17 Dec 2020 13:08:57 -0500 Received: from mail-lf1-x12f.google.com (mail-lf1-x12f.google.com [IPv6:2a00:1450:4864:20::12f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3AA28C061794; Thu, 17 Dec 2020 10:07:49 -0800 (PST) Received: by mail-lf1-x12f.google.com with SMTP id o19so34209261lfo.1; Thu, 17 Dec 2020 10:07:49 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=2xd7/yRqQ1bpLSBqqvPYmX9y9km1o1DPCdEu2/xdf8k=; b=knjqp1xwmZY1uipSsuIrAKlbV0FPromBnLXJv9W83vZ4UUD9iS/WzmlpXNbZhD+xJn SVAeMUogtUbshBqLuRHfAQSoeEPnAUD2yOgO+lP8Bv5/lzDv8qlofpqMefqRFy+qnU8y cmQWdkpzg8Ar4Ggr1+b1gKRJeePAZtWXiDMoiFncDbrbrSMtUGmP/E6F80FzVADdQkzy obs4CCg1a82jm+Qbii45XqQPDlOvSM0QVnq93k4Ac/PIR/SMRe3nDMizmTePuRTNAgHV BgBWlE/0wpha34e9hCrNtqDLLb1/sEbxoNPJESoXU299byDkUHyj1fP1p1mFO/Rl8rs3 DTPg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=2xd7/yRqQ1bpLSBqqvPYmX9y9km1o1DPCdEu2/xdf8k=; b=MZ1qSwhU1K9I9oTToP03+AhcFbm5CbWoo18ehBbi1rHt22ffm9MV1HNRlk0F/8jwfd seicjEMzZ3fMYSvZWRqkwurH2Wi//XPC/G9loyxFMz97ZEBWhE1cQSnZ6DpyAq83G4rc 5reGST/R8iXnr3nCs+ipQrHVh3fNlellFf2pObHChVfeoilexOWx2KIjoL+hqTTWZmlP zgfmcZ1PErAJJFGtlywawLBRUZeqHz9c6qw/qGzigodQINaXIM3oqVS1ZuH+i1PP0/8C go7QXOF3fIx9E7aU/IzjxnhmIRStZ+M6SzEgT/wPDVgRZk1QRVw/bouzfvkBeFOAJLWN rIpw== X-Gm-Message-State: AOAM532LphPMkjHSKJbNO5J/5B6ghdLpm66MmDlzx6iD/Zoze0TmEuyt acOxf2WHYBbyW546+2BfIDU= X-Google-Smtp-Source: ABdhPJxl5RroGj+GTUW6FyPBVu/AN/pYFQvr0N2HeyHSfmpalUAs6qNcm/28WYlCJIdj+T+0fIA9GQ== X-Received: by 2002:a19:9d8:: with SMTP id 207mr8275737lfj.581.1608228467753; Thu, 17 Dec 2020 10:07:47 -0800 (PST) Received: from localhost.localdomain (109-252-192-57.dynamic.spd-mgts.ru. [109.252.192.57]) by smtp.gmail.com with ESMTPSA id u5sm655596lff.78.2020.12.17.10.07.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 17 Dec 2020 10:07:47 -0800 (PST) From: Dmitry Osipenko To: Thierry Reding , Jonathan Hunter , Mark Brown , Liam Girdwood , Ulf Hansson , Mauro Carvalho Chehab , Rob Herring , Peter Geis , Nicolas Chauvet , Krzysztof Kozlowski , "Rafael J. Wysocki" , Kevin Hilman , Peter De Schrijver , Viresh Kumar , Stephen Boyd , Michael Turquette Cc: devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-media@vger.kernel.org, linux-tegra@vger.kernel.org, linux-clk@vger.kernel.org Subject: [PATCH v2 24/48] soc/tegra: pmc: Ensure that clock rates aren't too high Date: Thu, 17 Dec 2020 21:06:14 +0300 Message-Id: <20201217180638.22748-25-digetx@gmail.com> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201217180638.22748-1-digetx@gmail.com> References: <20201217180638.22748-1-digetx@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org Switch all clocks of a power domain to a safe rate which is suitable for all possible voltages in order to ensure that hardware constraints aren't violated when power domain state toggles. Signed-off-by: Dmitry Osipenko --- drivers/soc/tegra/pmc.c | 92 ++++++++++++++++++++++++++++++++++++++++- 1 file changed, 90 insertions(+), 2 deletions(-) diff --git a/drivers/soc/tegra/pmc.c b/drivers/soc/tegra/pmc.c index 985373ce52b1..8edcd5b319f6 100644 --- a/drivers/soc/tegra/pmc.c +++ b/drivers/soc/tegra/pmc.c @@ -237,6 +237,7 @@ struct tegra_powergate { unsigned int id; struct clk **clks; unsigned int num_clks; + unsigned long *clk_rates; struct reset_control *reset; }; @@ -586,6 +587,57 @@ static int __tegra_powergate_remove_clamping(struct tegra_pmc *pmc, return 0; } +static int tegra_powergate_prepare_clocks(struct tegra_powergate *pg) +{ + unsigned long safe_rate = 100 * 1000 * 1000; + unsigned int i; + int err; + + for (i = 0; i < pg->num_clks; i++) { + pg->clk_rates[i] = clk_get_rate(pg->clks[i]); + + if (!pg->clk_rates[i]) { + err = -EINVAL; + goto out; + } + + if (pg->clk_rates[i] <= safe_rate) + continue; + + /* + * We don't know whether voltage state is okay for the + * current clock rate, hence it's better to temporally + * switch clock to a safe rate which is suitable for + * all voltages, before enabling the clock. + */ + err = clk_set_rate(pg->clks[i], safe_rate); + if (err) + goto out; + } + + return 0; + +out: + while (i--) + clk_set_rate(pg->clks[i], pg->clk_rates[i]); + + return err; +} + +static int tegra_powergate_unprepare_clocks(struct tegra_powergate *pg) +{ + unsigned int i; + int err; + + for (i = 0; i < pg->num_clks; i++) { + err = clk_set_rate(pg->clks[i], pg->clk_rates[i]); + if (err) + return err; + } + + return 0; +} + static void tegra_powergate_disable_clocks(struct tegra_powergate *pg) { unsigned int i; @@ -636,10 +688,14 @@ static int tegra_powergate_power_up(struct tegra_powergate *pg, usleep_range(10, 20); - err = tegra_powergate_enable_clocks(pg); + err = tegra_powergate_prepare_clocks(pg); if (err) goto powergate_off; + err = tegra_powergate_enable_clocks(pg); + if (err) + goto unprepare_clks; + usleep_range(10, 20); err = __tegra_powergate_remove_clamping(pg->pmc, pg->id); @@ -670,12 +726,19 @@ static int tegra_powergate_power_up(struct tegra_powergate *pg, if (disable_clocks) tegra_powergate_disable_clocks(pg); + err = tegra_powergate_unprepare_clocks(pg); + if (err) + return err; + return 0; disable_clks: tegra_powergate_disable_clocks(pg); usleep_range(10, 20); +unprepare_clks: + tegra_powergate_unprepare_clocks(pg); + powergate_off: tegra_powergate_set(pg->pmc, pg->id, false); @@ -686,10 +749,14 @@ static int tegra_powergate_power_down(struct tegra_powergate *pg) { int err; - err = tegra_powergate_enable_clocks(pg); + err = tegra_powergate_prepare_clocks(pg); if (err) return err; + err = tegra_powergate_enable_clocks(pg); + if (err) + goto unprepare_clks; + usleep_range(10, 20); err = reset_control_assert(pg->reset); @@ -706,6 +773,10 @@ static int tegra_powergate_power_down(struct tegra_powergate *pg) if (err) goto assert_resets; + err = tegra_powergate_unprepare_clocks(pg); + if (err) + return err; + return 0; assert_resets: @@ -717,6 +788,9 @@ static int tegra_powergate_power_down(struct tegra_powergate *pg) disable_clks: tegra_powergate_disable_clocks(pg); +unprepare_clks: + tegra_powergate_unprepare_clocks(pg); + return err; } @@ -834,6 +908,12 @@ int tegra_powergate_sequence_power_up(unsigned int id, struct clk *clk, if (!pg) return -ENOMEM; + pg->clk_rates = kzalloc(sizeof(*pg->clk_rates), GFP_KERNEL); + if (!pg->clk_rates) { + kfree(pg->clks); + return -ENOMEM; + } + pg->id = id; pg->clks = &clk; pg->num_clks = 1; @@ -845,6 +925,7 @@ int tegra_powergate_sequence_power_up(unsigned int id, struct clk *clk, dev_err(pmc->dev, "failed to turn on partition %d: %d\n", id, err); + kfree(pg->clk_rates); kfree(pg); return err; @@ -995,6 +1076,12 @@ static int tegra_powergate_of_get_clks(struct tegra_powergate *pg, if (!pg->clks) return -ENOMEM; + pg->clk_rates = kcalloc(count, sizeof(*pg->clk_rates), GFP_KERNEL); + if (!pg->clk_rates) { + kfree(pg->clks); + return -ENOMEM; + } + for (i = 0; i < count; i++) { pg->clks[i] = of_clk_get(np, i); if (IS_ERR(pg->clks[i])) { @@ -1011,6 +1098,7 @@ static int tegra_powergate_of_get_clks(struct tegra_powergate *pg, while (i--) clk_put(pg->clks[i]); + kfree(pg->clk_rates); kfree(pg->clks); return err;