From patchwork Fri Nov 3 14:47:53 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sudeep Holla X-Patchwork-Id: 117926 Delivered-To: patch@linaro.org Received: by 10.80.245.45 with SMTP id t42csp3402949edm; Fri, 3 Nov 2017 07:50:37 -0700 (PDT) X-Google-Smtp-Source: ABhQp+RXzNpTt/GlYaJ++EWUtbVJHpCoKSkBpEYBWbq2tFMb3XAx8lorG/zeYWq2ArOjO7zVv2Hu X-Received: by 10.84.176.163 with SMTP id v32mr7079762plb.175.1509720637191; Fri, 03 Nov 2017 07:50:37 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1509720637; cv=none; d=google.com; s=arc-20160816; b=NDR8NmzQRlEqYwZssvSF9iTqxCCa2BWa4/3Yz/yCCd8i7CZ1y4svTbxrHBVJN+HfbC 8dXNf/Y/Mj4vo2nqXvtdMJq/XgvifpAiEZFmApforDk45d2vKzWrQJepqDiyDCB4lYkg Q1kPYGs3jO30jrDcIbKk9J6FgNyitWxgkPEiOguq5gC/CQjVe/Y7rnGyyhcuyU0lHUfw cGI5HBgU1VdqS/k7bnl8uvFny+jVRHEC+ID/V8WTGWihaWB1vHwlbkj0zh+C4g2CDMXN H0lsDSUVP9d0dNrBP5234aL4kbeQ2k9N+5H/Z76D+dSUpFXjTEp7rnAjEvuOpGHhnlVa 08xQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:references:in-reply-to:message-id:date :subject:cc:to:from:arc-authentication-results; bh=U2eePmsAA/TwHstuY2AlvsYlUmucFMYZVX49O9b8/6I=; b=TZv/sKCY1A7xnLMaZQIyne6LqgFxvjvh+uKyPG0sKuWRCAeAnek5Pze3HEOesGnNOY Fb/8Eht3Dm7uPB/QguztmFz4uuU4WYU7gAvwBa7lMkn6pw/yvSGqw7V5mNiMU+jcZDPn RvCCZ/mhyJSXx+fzZdYPkhGirfKpGe5XcqmTKYiN6NFvQukBIJMJ0HIWgG8KGB2pUw20 3MgtQ7hPPmYiK3J8NomCFeMyf95J1u0KSNUS2FC/1ZZOyRZ33BFJDQsOwhUzwFzdLNTw RcGoqzEotWL9BISFdsHH15kq5L/82Yt5px7RxWxKPmlPRX7Qbkghb41m47uLPylAthvS +CpQ== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id f68si6571313pfb.395.2017.11.03.07.50.36; Fri, 03 Nov 2017 07:50:37 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933875AbdKCOue (ORCPT + 26 others); Fri, 3 Nov 2017 10:50:34 -0400 Received: from foss.arm.com ([217.140.101.70]:44480 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933658AbdKCOt0 (ORCPT ); Fri, 3 Nov 2017 10:49:26 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 3A2FC19F6; Fri, 3 Nov 2017 07:49:26 -0700 (PDT) Received: from e107155-lin.cambridge.arm.com (e107155-lin.cambridge.arm.com [10.1.210.28]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 03F803F3DF; Fri, 3 Nov 2017 07:49:23 -0700 (PDT) From: Sudeep Holla To: ALKML , LKML , DTML Cc: Sudeep Holla , Roy Franz , Harb Abdulhamid , Nishanth Menon , Arnd Bergmann , Loc Ho , Ryan Harkin , Jassi Brar , linux-clk@vger.kernel.org, Michael Turquette Subject: [PATCH v4 16/20] clk: add support for clocks provided by SCMI Date: Fri, 3 Nov 2017 14:47:53 +0000 Message-Id: <1509720477-18936-17-git-send-email-sudeep.holla@arm.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1509720477-18936-1-git-send-email-sudeep.holla@arm.com> References: <1509720477-18936-1-git-send-email-sudeep.holla@arm.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On some ARM based systems, a separate Cortex-M based System Control Processor(SCP) provides the overall power, clock, reset and system control. System Control and Management Interface(SCMI) Message Protocol is defined for the communication between the Application Cores(AP) and the SCP. This patch adds support for the clocks provided by SCP using SCMI protocol. Cc: linux-clk@vger.kernel.org Cc: Michael Turquette Acked-by: Stephen Boyd Signed-off-by: Sudeep Holla --- MAINTAINERS | 2 +- drivers/clk/Kconfig | 10 +++ drivers/clk/Makefile | 1 + drivers/clk/clk-scmi.c | 213 +++++++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 225 insertions(+), 1 deletion(-) create mode 100644 drivers/clk/clk-scmi.c -- 2.7.4 diff --git a/MAINTAINERS b/MAINTAINERS index 8ee63627f1ac..1f9004d68ad4 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -12954,7 +12954,7 @@ M: Sudeep Holla L: linux-arm-kernel@lists.infradead.org S: Maintained F: Documentation/devicetree/bindings/arm/arm,sc[mp]i.txt -F: drivers/clk/clk-scpi.c +F: drivers/clk/clk-sc[mp]i.c F: drivers/cpufreq/scpi-cpufreq.c F: drivers/firmware/arm_scpi.c F: drivers/firmware/arm_scmi/ diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig index 1c4e1aa6767e..57c66b22eab8 100644 --- a/drivers/clk/Kconfig +++ b/drivers/clk/Kconfig @@ -62,6 +62,16 @@ config COMMON_CLK_HI655X multi-function device has one fixed-rate oscillator, clocked at 32KHz. +config COMMON_CLK_SCMI + tristate "Clock driver controlled via SCMI interface" + depends on ARM_SCMI_PROTOCOL || COMPILE_TEST + ---help--- + This driver provides support for clocks that are controlled + by firmware that implements the SCMI interface. + + This driver uses SCMI Message Protocol to interact with the + firmware providing all the clock controls. + config COMMON_CLK_SCPI tristate "Clock driver controlled via SCPI interface" depends on ARM_SCPI_PROTOCOL || COMPILE_TEST diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile index c99f363826f0..46ad2f2b686a 100644 --- a/drivers/clk/Makefile +++ b/drivers/clk/Makefile @@ -39,6 +39,7 @@ obj-$(CONFIG_CLK_QORIQ) += clk-qoriq.o obj-$(CONFIG_COMMON_CLK_RK808) += clk-rk808.o obj-$(CONFIG_COMMON_CLK_HI655X) += clk-hi655x.o obj-$(CONFIG_COMMON_CLK_S2MPS11) += clk-s2mps11.o +obj-$(CONFIG_COMMON_CLK_SCMI) += clk-scmi.o obj-$(CONFIG_COMMON_CLK_SCPI) += clk-scpi.o obj-$(CONFIG_COMMON_CLK_SI5351) += clk-si5351.o obj-$(CONFIG_COMMON_CLK_SI514) += clk-si514.o diff --git a/drivers/clk/clk-scmi.c b/drivers/clk/clk-scmi.c new file mode 100644 index 000000000000..1e4d7a57779b --- /dev/null +++ b/drivers/clk/clk-scmi.c @@ -0,0 +1,213 @@ +/* + * System Control and Power Interface (SCMI) Protocol based clock driver + * + * Copyright (C) 2017 ARM Ltd. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope 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. + * + * You should have received a copy of the GNU General Public License along with + * this program. If not, see . + */ + +#include +#include +#include +#include +#include +#include +#include + +struct scmi_clk { + u32 id; + struct clk_hw hw; + const struct scmi_clock_info *info; + const struct scmi_handle *handle; +}; + +#define to_scmi_clk(clk) container_of(clk, struct scmi_clk, hw) + +static unsigned long scmi_clk_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + int ret; + u64 rate; + struct scmi_clk *clk = to_scmi_clk(hw); + + ret = clk->handle->clk_ops->rate_get(clk->handle, clk->id, &rate); + if (ret) + return 0; + return rate; +} + +static long scmi_clk_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *parent_rate) +{ + int step; + u64 fmin, fmax, ftmp; + struct scmi_clk *clk = to_scmi_clk(hw); + + /* + * We can't figure out what rate it will be, so just return the + * rate back to the caller. scmi_clk_recalc_rate() will be called + * after the rate is set and we'll know what rate the clock is + * running at then. + */ + if (clk->info->rate_discrete) + return rate; + + fmin = clk->info->range.min_rate; + fmax = clk->info->range.max_rate; + if (rate <= fmin) + return fmin; + else if (rate >= fmax) + return fmax; + + ftmp = rate - fmin; + ftmp += clk->info->range.step_size - 1; /* to round up */ + step = do_div(ftmp, clk->info->range.step_size); + + return step * clk->info->range.step_size + fmin; +} + +static int scmi_clk_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct scmi_clk *clk = to_scmi_clk(hw); + + return clk->handle->clk_ops->rate_set(clk->handle, clk->id, 0, rate); +} + +static int scmi_clk_enable(struct clk_hw *hw) +{ + struct scmi_clk *clk = to_scmi_clk(hw); + + return clk->handle->clk_ops->enable(clk->handle, clk->id); +} + +static void scmi_clk_disable(struct clk_hw *hw) +{ + struct scmi_clk *clk = to_scmi_clk(hw); + + clk->handle->clk_ops->disable(clk->handle, clk->id); +} + +static const struct clk_ops scmi_clk_ops = { + .recalc_rate = scmi_clk_recalc_rate, + .round_rate = scmi_clk_round_rate, + .set_rate = scmi_clk_set_rate, + /* + * We can't provide enable/disable callback as we can't perform the same + * in atomic context. Since the clock framework provides standard API + * clk_prepare_enable that helps cases using clk_enable in non-atomic + * context, it should be fine providing prepare/unprepare. + */ + .prepare = scmi_clk_enable, + .unprepare = scmi_clk_disable, +}; + +static int scmi_clk_ops_init(struct device *dev, struct scmi_clk *sclk) +{ + int ret; + struct clk_init_data init = { + .flags = CLK_GET_RATE_NOCACHE, + .num_parents = 0, + .ops = &scmi_clk_ops, + .name = sclk->info->name, + }; + + sclk->hw.init = &init; + ret = devm_clk_hw_register(dev, &sclk->hw); + if (!ret) + clk_hw_set_rate_range(&sclk->hw, sclk->info->range.min_rate, + sclk->info->range.max_rate); + return ret; +} + +static int scmi_clocks_probe(struct scmi_device *sdev) +{ + int idx, count, err; + struct clk_hw **hws; + struct clk_hw_onecell_data *clk_data; + struct device *dev = &sdev->dev; + struct device_node *np = dev->of_node; + const struct scmi_handle *handle = sdev->handle; + + if (!handle || !handle->clk_ops) + return -ENODEV; + + count = handle->clk_ops->count_get(handle); + if (count < 0) { + dev_err(dev, "%s: invalid clock output count\n", np->name); + return -EINVAL; + } + + clk_data = devm_kzalloc(dev, sizeof(*clk_data) + + sizeof(*clk_data->hws) * count, GFP_KERNEL); + if (!clk_data) + return -ENOMEM; + + clk_data->num = count; + hws = clk_data->hws; + + for (idx = 0; idx < count; idx++) { + struct scmi_clk *sclk; + + sclk = devm_kzalloc(dev, sizeof(*sclk), GFP_KERNEL); + if (!sclk) + return -ENOMEM; + + sclk->info = handle->clk_ops->info_get(handle, idx); + if (!sclk->info) { + dev_dbg(dev, "invalid clock info for idx %d\n", idx); + continue; + } + + sclk->id = idx; + sclk->handle = handle; + + err = scmi_clk_ops_init(dev, sclk); + if (err) { + dev_err(dev, "failed to register clock %d\n", idx); + devm_kfree(dev, sclk); + hws[idx] = NULL; + } else { + dev_dbg(dev, "Registered clock:%s\n", sclk->info->name); + hws[idx] = &sclk->hw; + } + } + + return of_clk_add_hw_provider(np, of_clk_hw_onecell_get, clk_data); +} + +static void scmi_clocks_remove(struct scmi_device *sdev) +{ + struct device *dev = &sdev->dev; + struct device_node *np = dev->of_node; + + of_clk_del_provider(np); +} + +static const struct scmi_device_id scmi_id_table[] = { + { SCMI_PROTOCOL_CLOCK }, + { }, +}; +MODULE_DEVICE_TABLE(scmi, scmi_id_table); + +static struct scmi_driver scmi_clocks_driver = { + .name = "scmi-clocks", + .probe = scmi_clocks_probe, + .remove = scmi_clocks_remove, + .id_table = scmi_id_table, +}; +module_scmi_driver(scmi_clocks_driver); + +MODULE_AUTHOR("Sudeep Holla "); +MODULE_DESCRIPTION("ARM SCMI clock driver"); +MODULE_LICENSE("GPL v2");