From patchwork Mon Jul 21 15:38:52 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tuomas Tynkkynen X-Patchwork-Id: 4596921 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 7233FC0515 for ; Mon, 21 Jul 2014 15:44:52 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 72B0D200DB for ; Mon, 21 Jul 2014 15:44:51 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 99235200E1 for ; Mon, 21 Jul 2014 15:44:49 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1X9FjD-0006zv-7q; Mon, 21 Jul 2014 15:42:15 +0000 Received: from hqemgate15.nvidia.com ([216.228.121.64]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1X9Fhe-00055S-9h for linux-arm-kernel@lists.infradead.org; Mon, 21 Jul 2014 15:40:39 +0000 Received: from hqnvupgp07.nvidia.com (Not Verified[216.228.121.13]) by hqemgate15.nvidia.com id ; Mon, 21 Jul 2014 08:39:52 -0700 Received: from hqemhub01.nvidia.com ([172.20.12.94]) by hqnvupgp07.nvidia.com (PGP Universal service); Mon, 21 Jul 2014 08:28:19 -0700 X-PGP-Universal: processed; by hqnvupgp07.nvidia.com on Mon, 21 Jul 2014 08:28:19 -0700 Received: from ttynkkynen-lnx.Nvidia.com (172.20.144.16) by hqemhub01.nvidia.com (172.20.150.30) with Microsoft SMTP Server id 8.3.342.0; Mon, 21 Jul 2014 08:39:58 -0700 From: Tuomas Tynkkynen To: , , , Subject: [PATCH v2 06/16] clk: tegra: Add functions for parsing CVB tables Date: Mon, 21 Jul 2014 18:38:52 +0300 Message-ID: <1405957142-19416-7-git-send-email-ttynkkynen@nvidia.com> X-Mailer: git-send-email 1.8.1.5 In-Reply-To: <1405957142-19416-1-git-send-email-ttynkkynen@nvidia.com> References: <1405957142-19416-1-git-send-email-ttynkkynen@nvidia.com> X-NVConfidentiality: public MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20140721_084038_369980_D900D51E X-CRM114-Status: GOOD ( 24.46 ) X-Spam-Score: -0.0 (/) Cc: devicetree@vger.kernel.org, Prashant Gaikwad , Mike Turquette , Stephen Warren , Viresh Kumar , Peter De Schrijver , "Rafael J. Wysocki" , Thierry Reding , Tuomas Tynkkynen , Paul Walmsley X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Tegra CVB tables encode the relationship between operating voltage and optimal frequency as a second-order polynomial of the so-called speedo value. The speedo value is written to the on-chip fuses at the factory, which allows the voltage-frequency operating points to be calculated on an per-chip basis. Add utility functions to parse the Tegra-specific tables and export the voltage-frequency pairs to the generic OPP framework for other drivers to use. Signed-off-by: Tuomas Tynkkynen --- v2 changes: - none arch/arm/mach-tegra/Kconfig | 1 + drivers/clk/tegra/cvb.c | 133 ++++++++++++++++++++++++++++++++++++++++++++ drivers/clk/tegra/cvb.h | 67 ++++++++++++++++++++++ 3 files changed, 201 insertions(+) create mode 100644 drivers/clk/tegra/cvb.c create mode 100644 drivers/clk/tegra/cvb.h diff --git a/arch/arm/mach-tegra/Kconfig b/arch/arm/mach-tegra/Kconfig index 0953996..0d5832f 100644 --- a/arch/arm/mach-tegra/Kconfig +++ b/arch/arm/mach-tegra/Kconfig @@ -7,6 +7,7 @@ menuconfig ARCH_TEGRA select HAVE_ARM_SCU if SMP select HAVE_ARM_TWD if SMP select PINCTRL + select PM_OPP select ARCH_HAS_RESET_CONTROLLER select RESET_CONTROLLER select SOC_BUS diff --git a/drivers/clk/tegra/cvb.c b/drivers/clk/tegra/cvb.c new file mode 100644 index 0000000..69c74ee --- /dev/null +++ b/drivers/clk/tegra/cvb.c @@ -0,0 +1,133 @@ +/* + * Utility functions for parsing Tegra CVB voltage tables + * + * Copyright (C) 2012-2014 NVIDIA Corporation. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + */ +#include +#include +#include + +#include "cvb.h" + +/* cvb_mv = ((c2 * speedo / s_scale + c1) * speedo / s_scale + c0) */ +static inline int get_cvb_voltage(int speedo, int s_scale, + const struct cvb_coefficients *cvb) +{ + int mv; + + /* apply only speedo scale: output mv = cvb_mv * v_scale */ + mv = DIV_ROUND_CLOSEST(cvb->c2 * speedo, s_scale); + mv = DIV_ROUND_CLOSEST((mv + cvb->c1) * speedo, s_scale) + cvb->c0; + return mv; +} + +static int round_cvb_voltage(int mv, int v_scale, + const struct rail_alignment *align) +{ + /* combined: apply voltage scale and round to cvb alignment step */ + int uv; + int step = (align->step_uv ? : 1000) * v_scale; + int offset = align->offset_uv * v_scale; + + uv = max(mv * 1000, offset) - offset; + uv = DIV_ROUND_UP(uv, step) * align->step_uv + align->offset_uv; + return uv / 1000; +} + +enum { + DOWN, + UP +}; + +static int round_voltage(int mv, const struct rail_alignment *align, int up) +{ + if (align->step_uv) { + int uv; + + uv = max(mv * 1000, align->offset_uv) - align->offset_uv; + uv = (uv + (up ? align->step_uv - 1 : 0)) / align->step_uv; + return (uv * align->step_uv + align->offset_uv) / 1000; + } + return mv; +} + +static int build_opp_table(const struct cvb_table *d, + int speedo_value, + unsigned long max_freq, + struct device *opp_dev) +{ + int i, ret, dfll_mv, min_mv, max_mv; + const struct cvb_table_freq_entry *table = NULL; + const struct rail_alignment *align = &d->alignment; + + min_mv = round_voltage(d->min_millivolts, align, UP); + max_mv = round_voltage(d->max_millivolts, align, DOWN); + + for (i = 0; i < MAX_DVFS_FREQS; i++) { + table = &d->cvb_table[i]; + if (!table->freq || (table->freq > max_freq)) + break; + + dfll_mv = get_cvb_voltage( + speedo_value, d->speedo_scale, &table->coefficients); + dfll_mv = round_cvb_voltage(dfll_mv, d->voltage_scale, align); + dfll_mv = clamp(dfll_mv, min_mv, max_mv); + + ret = dev_pm_opp_add(opp_dev, table->freq, dfll_mv * 1000); + if (ret) + return ret; + } + + return 0; +} + +/** + * tegra_cvb_build_opp_table - build OPP table from Tegra CVB tables + * @cvb_tables: array of CVB tables + * @sz: size of the previously mentioned array + * @process_id: process id of the HW module + * @speedo_id: speedo id of the HW module + * @speedo_value: speedo value of the HW module + * @max_rate: highest safe clock rate + * @opp_dev: the struct device * for which the OPP table is built + * + * On Tegra, a CVB table encodes the relationship between operating voltage + * and safe maximal frequency for a given module (e.g. GPU or CPU). This + * function calculates the optimal voltage-frequency operating points + * for the given arguments and exports them via the OPP library for the + * given @opp_dev. Returns a pointer to the struct cvb_table that matched + * or an ERR_PTR on failure. + */ +const struct cvb_table *tegra_cvb_build_opp_table( + const struct cvb_table *cvb_tables, + size_t sz, int process_id, + int speedo_id, int speedo_value, + unsigned long max_rate, + struct device *opp_dev) +{ + int i, ret; + + for (i = 0; i < sz; i++) { + const struct cvb_table *d = &cvb_tables[i]; + + if (d->speedo_id != -1 && d->speedo_id != speedo_id) + continue; + if (d->process_id != -1 && d->process_id != process_id) + continue; + + ret = build_opp_table(d, speedo_value, max_rate, opp_dev); + return ret ? ERR_PTR(ret) : d; + } + + return ERR_PTR(-EINVAL); +} diff --git a/drivers/clk/tegra/cvb.h b/drivers/clk/tegra/cvb.h new file mode 100644 index 0000000..f62cdc4 --- /dev/null +++ b/drivers/clk/tegra/cvb.h @@ -0,0 +1,67 @@ +/* + * Utility functions for parsing Tegra CVB voltage tables + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + */ + +#ifndef __DRIVERS_CLK_TEGRA_CVB_H +#define __DRIVERS_CLK_TEGRA_CVB_H + +#include + +struct device; + +#define MAX_DVFS_FREQS 40 + +struct rail_alignment { + int offset_uv; + int step_uv; +}; + +struct cvb_coefficients { + int c0; + int c1; + int c2; +}; + +struct cvb_table_freq_entry { + unsigned long freq; + struct cvb_coefficients coefficients; +}; + +struct cvb_cpu_dfll_data { + u32 tune0_low; + u32 tune0_high; + u32 tune1; +}; + +struct cvb_table { + int speedo_id; + int process_id; + + int min_millivolts; + int max_millivolts; + struct rail_alignment alignment; + + int speedo_scale; + int voltage_scale; + struct cvb_table_freq_entry cvb_table[MAX_DVFS_FREQS]; + struct cvb_cpu_dfll_data cpu_dfll_data; +}; + +const struct cvb_table *tegra_cvb_build_opp_table( + const struct cvb_table *cvb_tables, + size_t sz, int process_id, + int speedo_id, int speedo_value, + unsigned long max_rate, + struct device *opp_dev); + +#endif