From mboxrd@z Thu Jan 1 00:00:00 1970 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=-8.7 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_PASS,USER_AGENT_MUTT 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 1FB21C43387 for ; Fri, 14 Dec 2018 17:30:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E9FA3206C0 for ; Fri, 14 Dec 2018 17:30:18 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="QPlp0L7j" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730393AbeLNRaQ (ORCPT ); Fri, 14 Dec 2018 12:30:16 -0500 Received: from mail-pg1-f195.google.com ([209.85.215.195]:41144 "EHLO mail-pg1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730063AbeLNRaQ (ORCPT ); Fri, 14 Dec 2018 12:30:16 -0500 Received: by mail-pg1-f195.google.com with SMTP id m1so1360388pgq.8 for ; Fri, 14 Dec 2018 09:30:15 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=RCMJnv/8TopEp5Ur3v15RtFMvPv7LWMP7+jtECQcPOc=; b=QPlp0L7jH0nz46lHOvITqfpXx6zalDTA1C+97r67o/rkrl7ynryBp5GyV4+6Q+K2SN KYTJnBCFVU8EYDTHfA73jGyC9gEwk3tg8AH8LISkLGYd5wePPLNK91vWGJ9jTqwGaaGY Cq9DxapGKqhn7yMhlFtTO2XynqJsZAOdy0Qpk= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=RCMJnv/8TopEp5Ur3v15RtFMvPv7LWMP7+jtECQcPOc=; b=U8Ihd51+JkHHiDPaxObxWrIgD0VRtULXvXs/7Jo0j2AL+L4m3DamlDuYjnxwGyORVL 1APm8wXk116JTJCecEx6grE56I5v5ISL66jvkRfBFoXfEsDbtiTBEA19KBjQaU7HHJIL E2h0NXzH/tN7cFIXIxJPCKRWPIjE+3U9bdThSpvPUJBbfYP3CCu9VLclZ8O/UMh+iCUC CR5I/RbpnS1oGAnP4lAvsWOEak1YZ+igVWQySyNZtCNaeS+GNzi4GZ7EQS67YPPpQBgs 9y5yHBYkWI9bGgJBKetVaFcD6BjSuBzT+fCtb5YdBtRflhh0INhS/pvzBCpnzRI+NcFS mFRA== X-Gm-Message-State: AA+aEWa7UAFy++36N5wGV8hMwoO7VTgMcziYL6jlYKwwPqs+7aFeNBjI DujKCVXPrA3jyFWP+HkBTm3ueg== X-Google-Smtp-Source: AFSGD/XJVnxxODDEG4FXTDQjEgHHeIBjVZ0q0TK2tyR22sRgzFxzoET19EY7Y9H0/BONL3rqOhLcew== X-Received: by 2002:a62:81c1:: with SMTP id t184mr3781638pfd.40.1544808615218; Fri, 14 Dec 2018 09:30:15 -0800 (PST) Received: from localhost ([2620:15c:202:1:75a:3f6e:21d:9374]) by smtp.gmail.com with ESMTPSA id 128sm8401301pfu.129.2018.12.14.09.30.14 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Fri, 14 Dec 2018 09:30:14 -0800 (PST) Date: Fri, 14 Dec 2018 09:30:13 -0800 From: Matthias Kaehlcke To: Taniya Das Cc: "Rafael J. Wysocki" , Viresh Kumar , linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, Stephen Boyd , Rajendra Nayak , devicetree@vger.kernel.org, robh@kernel.org, skannan@codeaurora.org, linux-arm-msm@vger.kernel.org, evgreen@google.com, Stephen Boyd Subject: Re: [PATCH v13 2/2] cpufreq: qcom-hw: Add support for QCOM cpufreq HW driver Message-ID: <20181214173013.GA109358@google.com> References: <1544760624-12874-1-git-send-email-tdas@codeaurora.org> <1544760624-12874-3-git-send-email-tdas@codeaurora.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <1544760624-12874-3-git-send-email-tdas@codeaurora.org> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Dec 14, 2018 at 09:40:24AM +0530, Taniya Das wrote: > The CPUfreq HW present in some QCOM chipsets offloads the steps necessary > for changing the frequency of CPUs. The driver implements the cpufreq > driver interface for this hardware engine. > > Signed-off-by: Saravana Kannan > Signed-off-by: Stephen Boyd > Signed-off-by: Taniya Das I think it's common practice to carry over tags like 'Reviewed-by' or 'Acked-by' for trivial changes. > --- > drivers/cpufreq/Kconfig.arm | 11 ++ > drivers/cpufreq/Makefile | 1 + > drivers/cpufreq/qcom-cpufreq-hw.c | 308 ++++++++++++++++++++++++++++++++++++++ > 3 files changed, 320 insertions(+) > create mode 100644 drivers/cpufreq/qcom-cpufreq-hw.c > > diff --git a/drivers/cpufreq/Kconfig.arm b/drivers/cpufreq/Kconfig.arm > index 4e1131e..688f102 100644 > --- a/drivers/cpufreq/Kconfig.arm > +++ b/drivers/cpufreq/Kconfig.arm > @@ -114,6 +114,17 @@ config ARM_QCOM_CPUFREQ_KRYO > > If in doubt, say N. > > +config ARM_QCOM_CPUFREQ_HW > + tristate "QCOM CPUFreq HW driver" > + depends on ARCH_QCOM || COMPILE_TEST > + help > + Support for the CPUFreq HW driver. > + Some QCOM chipsets have a HW engine to offload the steps > + necessary for changing the frequency of the CPUs. Firmware loaded > + in this engine exposes a programming interface to the OS. > + The driver implements the cpufreq interface for this HW engine. > + Say Y if you want to support CPUFreq HW. > + > config ARM_S3C_CPUFREQ > bool > help > diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile > index d5ee456..08c071b 100644 > --- a/drivers/cpufreq/Makefile > +++ b/drivers/cpufreq/Makefile > @@ -61,6 +61,7 @@ obj-$(CONFIG_MACH_MVEBU_V7) += mvebu-cpufreq.o > obj-$(CONFIG_ARM_OMAP2PLUS_CPUFREQ) += omap-cpufreq.o > obj-$(CONFIG_ARM_PXA2xx_CPUFREQ) += pxa2xx-cpufreq.o > obj-$(CONFIG_PXA3xx) += pxa3xx-cpufreq.o > +obj-$(CONFIG_ARM_QCOM_CPUFREQ_HW) += qcom-cpufreq-hw.o > obj-$(CONFIG_ARM_QCOM_CPUFREQ_KRYO) += qcom-cpufreq-kryo.o > obj-$(CONFIG_ARM_S3C2410_CPUFREQ) += s3c2410-cpufreq.o > obj-$(CONFIG_ARM_S3C2412_CPUFREQ) += s3c2412-cpufreq.o > diff --git a/drivers/cpufreq/qcom-cpufreq-hw.c b/drivers/cpufreq/qcom-cpufreq-hw.c > new file mode 100644 > index 0000000..d83939a > --- /dev/null > +++ b/drivers/cpufreq/qcom-cpufreq-hw.c > @@ -0,0 +1,308 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Copyright (c) 2018, The Linux Foundation. All rights reserved. > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +#define LUT_MAX_ENTRIES 40U > +#define LUT_SRC GENMASK(31, 30) > +#define LUT_L_VAL GENMASK(7, 0) > +#define LUT_CORE_COUNT GENMASK(18, 16) > +#define LUT_ROW_SIZE 32 > +#define CLK_HW_DIV 2 > + > +/* Register offsets */ > +#define REG_ENABLE 0x0 > +#define REG_LUT_TABLE 0x110 > +#define REG_PERF_STATE 0x920 > + > +static unsigned long cpu_hw_rate, xo_rate; > +static struct platform_device *global_pdev; > + > +static int qcom_cpufreq_hw_target_index(struct cpufreq_policy *policy, > + unsigned int index) > +{ > + void __iomem *perf_state_reg = policy->driver_data; > + > + writel_relaxed(index, perf_state_reg); > + > + return 0; > +} > + > +static unsigned int qcom_cpufreq_hw_get(unsigned int cpu) > +{ > + void __iomem *perf_state_reg; > + struct cpufreq_policy *policy; > + unsigned int index; > + > + policy = cpufreq_cpu_get_raw(cpu); > + if (!policy) > + return 0; > + > + perf_state_reg = policy->driver_data; > + > + index = readl_relaxed(perf_state_reg); > + index = min(index, LUT_MAX_ENTRIES - 1); > + > + return policy->freq_table[index].frequency; > +} > + > +static unsigned int qcom_cpufreq_hw_fast_switch(struct cpufreq_policy *policy, > + unsigned int target_freq) > +{ > + void __iomem *perf_state_reg = policy->driver_data; > + int index; > + > + index = policy->cached_resolved_idx; > + if (index < 0) > + return 0; > + > + writel_relaxed(index, perf_state_reg); > + > + return policy->freq_table[index].frequency; > +} > + > +static int qcom_cpufreq_hw_read_lut(struct device *dev, > + struct cpufreq_policy *policy, > + void __iomem *base) > +{ > + u32 data, src, lval, i, core_count, prev_cc = 0, prev_freq = 0, freq; > + unsigned int max_cores = cpumask_weight(policy->cpus); > + struct cpufreq_frequency_table *table; > + > + table = kcalloc(LUT_MAX_ENTRIES + 1, sizeof(*table), GFP_KERNEL); > + if (!table) > + return -ENOMEM; > + > + for (i = 0; i < LUT_MAX_ENTRIES; i++) { > + data = readl_relaxed(base + REG_LUT_TABLE + i * LUT_ROW_SIZE); > + src = FIELD_GET(LUT_SRC, data); > + lval = FIELD_GET(LUT_L_VAL, data); > + core_count = FIELD_GET(LUT_CORE_COUNT, data); > + > + if (src) > + freq = xo_rate * lval / 1000; > + else > + freq = cpu_hw_rate / 1000; > + > + /* Ignore boosts in the middle of the table */ > + if (core_count != max_cores) { > + table[i].frequency = CPUFREQ_ENTRY_INVALID; > + } else { > + table[i].frequency = freq; > + dev_dbg(dev, "index=%d freq=%d, core_count %d\n", i, > + freq, core_count); > + } > + > + /* > + * Two of the same frequencies with the same core counts means > + * end of table > + */ > + if (i > 0 && prev_freq == freq && prev_cc == core_count) { > + struct cpufreq_frequency_table *prev = &table[i - 1]; > + > + /* > + * Only treat the last frequency that might be a boost > + * as the boost frequency > + */ > + if (prev_cc != max_cores) { > + prev->frequency = prev_freq; > + prev->flags = CPUFREQ_BOOST_FREQ; > + } > + > + break; > + } > + > + prev_cc = core_count; > + prev_freq = freq; > + } > + > + table[i].frequency = CPUFREQ_TABLE_END; > + policy->freq_table = table; > + > + return 0; > +} > + > +static void qcom_get_related_cpus(int index, struct cpumask *m) > +{ > + struct device_node *cpu_np; > + struct of_phandle_args args; > + int cpu, ret; > + > + for_each_possible_cpu(cpu) { > + cpu_np = of_cpu_device_node_get(cpu); > + if (!cpu_np) > + continue; > + > + ret = of_parse_phandle_with_args(cpu_np, "qcom,freq-domain", > + "#freq-domain-cells", 0, > + &args); > + of_node_put(cpu_np); > + if (ret < 0) > + continue; > + > + if (index == args.args[0]) > + cpumask_set_cpu(cpu, m); > + } > +} > + > +static int qcom_cpufreq_hw_cpu_init(struct cpufreq_policy *policy) > +{ > + struct device *dev = &global_pdev->dev; > + struct of_phandle_args args; > + struct device_node *cpu_np; > + struct resource *res; > + void __iomem *base; > + int ret, index; > + > + cpu_np = of_cpu_device_node_get(policy->cpu); > + if (!cpu_np) > + return -EINVAL; > + > + ret = of_parse_phandle_with_args(cpu_np, "qcom,freq-domain", > + "#freq-domain-cells", 0, &args); > + of_node_put(cpu_np); > + if (ret) > + return ret; > + > + index = args.args[0]; > + > + res = platform_get_resource(global_pdev, IORESOURCE_MEM, index); > + if (!res) > + return -ENODEV; > + > + base = devm_ioremap(dev, res->start, resource_size(res)); > + if (!base) > + return -ENOMEM; > + > + /* HW should be in enabled state to proceed */ > + if (!(readl_relaxed(base + REG_ENABLE) & 0x1)) { > + dev_err(dev, "Domain-%d cpufreq hardware not enabled\n", index); > + ret = -ENODEV; > + goto error; > + } > + > + qcom_get_related_cpus(index, policy->cpus); > + if (!cpumask_weight(policy->cpus)) { > + dev_err(dev, "Domain-%d failed to get related CPUs\n", index); > + ret = -ENOENT; > + goto error; > + } > + > + policy->driver_data = base + REG_PERF_STATE; > + > + ret = qcom_cpufreq_hw_read_lut(dev, policy, base); > + if (ret) { > + dev_err(dev, "Domain-%d failed to read LUT\n", index); > + goto error; > + } > + > + policy->fast_switch_possible = true; > + > + return 0; > +error: > + devm_iounmap(dev, base); > + return ret; > +} > + > +static int qcom_cpufreq_hw_cpu_exit(struct cpufreq_policy *policy) > +{ > + void __iomem *base = policy->driver_data - REG_PERF_STATE; > + > + kfree(policy->freq_table); > + devm_iounmap(&global_pdev->dev, base); > + > + return 0; > +} > + > +static struct freq_attr *qcom_cpufreq_hw_attr[] = { > + &cpufreq_freq_attr_scaling_available_freqs, > + &cpufreq_freq_attr_scaling_boost_freqs, > + NULL > +}; > + > +static struct cpufreq_driver cpufreq_qcom_hw_driver = { > + .flags = CPUFREQ_STICKY | CPUFREQ_NEED_INITIAL_FREQ_CHECK | > + CPUFREQ_HAVE_GOVERNOR_PER_POLICY, > + .verify = cpufreq_generic_frequency_table_verify, > + .target_index = qcom_cpufreq_hw_target_index, > + .get = qcom_cpufreq_hw_get, > + .init = qcom_cpufreq_hw_cpu_init, > + .exit = qcom_cpufreq_hw_cpu_exit, > + .fast_switch = qcom_cpufreq_hw_fast_switch, > + .name = "qcom-cpufreq-hw", > + .attr = qcom_cpufreq_hw_attr, > +}; > + > +static int qcom_cpufreq_hw_driver_probe(struct platform_device *pdev) > +{ > + struct clk *clk; > + int ret; > + > + clk = clk_get(&pdev->dev, "xo"); > + if (IS_ERR(clk)) > + return PTR_ERR(clk); > + > + xo_rate = clk_get_rate(clk); > + clk_put(clk); > + > + clk = clk_get(&pdev->dev, "alternate"); > + if (IS_ERR(clk)) > + return PTR_ERR(clk); > + > + cpu_hw_rate = clk_get_rate(clk) / CLK_HW_DIV; > + clk_put(clk); > + > + global_pdev = pdev; > + > + ret = cpufreq_register_driver(&cpufreq_qcom_hw_driver); > + if (ret) > + dev_err(&pdev->dev, "CPUFreq HW driver failed to register\n"); > + else > + dev_dbg(&pdev->dev, "QCOM CPUFreq HW driver initialized\n"); > + > + return ret; > +} > + > +static int qcom_cpufreq_hw_driver_remove(struct platform_device *pdev) > +{ > + return cpufreq_unregister_driver(&cpufreq_qcom_hw_driver); > +} > + > +static const struct of_device_id qcom_cpufreq_hw_match[] = { > + { .compatible = "qcom,cpufreq-hw" }, > + {} > +}; > +MODULE_DEVICE_TABLE(of, qcom_cpufreq_hw_match); > + > +static struct platform_driver qcom_cpufreq_hw_driver = { > + .probe = qcom_cpufreq_hw_driver_probe, > + .remove = qcom_cpufreq_hw_driver_remove, > + .driver = { > + .name = "qcom-cpufreq-hw", > + .of_match_table = qcom_cpufreq_hw_match, > + }, > +}; > + > +static int __init qcom_cpufreq_hw_init(void) > +{ > + return platform_driver_register(&qcom_cpufreq_hw_driver); > +} > +subsys_initcall(qcom_cpufreq_hw_init); > + > +static void __exit qcom_cpufreq_hw_exit(void) > +{ > + platform_driver_unregister(&qcom_cpufreq_hw_driver); > +} > +module_exit(qcom_cpufreq_hw_exit); > + > +MODULE_DESCRIPTION("QCOM CPUFREQ HW Driver"); > +MODULE_LICENSE("GPL v2"); Reviewed-by: Matthias Kaehlcke