From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AH8x226lC02b2zcbGN6SFIgVuzbmLqSEVsWwMYlHhotYOFYHjqeVHKVAdGrww5nKQNkJPBXs/MwN ARC-Seal: i=1; a=rsa-sha256; t=1518461168; cv=none; d=google.com; s=arc-20160816; b=fnPOvsTqLoJKPfrPiSpb2mOfZqf74B0MBueL9hkNz5w5+7ppw9LnddyRD7H7Swa7FD Q8xzacLVsAmYJeS5f/Sgp5sZ9/WooHmkPIe8DMxJJdJVC9Dpn3NOLuCGXiNjuemrEYvZ 5t6B1ef6/CvePNanaZDKk1Pqk3LbK+jLkBQiBU4A8AShI50ELgghO3btyjmats/mzhuI m27wBNTQp8q6zdHf8MoAJsC7frnEOPmc8WxaUfO5N5YhrAyL57j1WBDL0JgVCIjwYBZR iChomgQytwp/u9PzM3sN459j1joIOZX/NbHtS1d1ELHX8mrOYiCLvv/BFs3wmXyWh+7H TwgA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=references:in-reply-to:message-id:date:subject:cc:to:from :arc-authentication-results; bh=9k6KTPoq/IXHX4nT2upADuz2ZAmqG7rGHn05db046JY=; b=AmuGD//5WBH1Ibmgld4dQwOgXag36L3LxzS0UcYmIr2IDXh/9ZVwbLPRy6U0Ihko21 dJkUGFolz+HhXajI1bIleN0VFwbqxNAlABA8Ii2ZKietKIY5EamDed3JFs6A4xiujAne T17WcCvsfX8lhaA3YNoUYGOihL2e7s8FLijuhas1+VodSDvsUmq5SIgauruSsg0xOBPj 4UtfvcaT3mfxq7A+TKY+K35dO+RD9Z88w+odnvZ9c4D9Kkk03L4sRPsdkPFPHwWaD7jW Cfv5Qk6MrGhVeaN1d28ndkbaBHTHxCSdXpAv5hVhKgPhryZJMSIkqywQJn6nGdekron/ LUHw== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of sudeep.holla@arm.com designates 217.140.101.70 as permitted sender) smtp.mailfrom=sudeep.holla@arm.com Authentication-Results: mx.google.com; spf=pass (google.com: domain of sudeep.holla@arm.com designates 217.140.101.70 as permitted sender) smtp.mailfrom=sudeep.holla@arm.com From: Sudeep Holla To: ALKML , LKML , DTML Cc: Sudeep Holla , Greg Kroah-Hartman , Arnd Bergmann , Alexey Klimov , linux-clk@vger.kernel.org, Michael Turquette Subject: [PATCH v5 16/20] clk: add support for clocks provided by SCMI Date: Mon, 12 Feb 2018 18:45:20 +0000 Message-Id: <1518461124-17371-17-git-send-email-sudeep.holla@arm.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1518461124-17371-1-git-send-email-sudeep.holla@arm.com> References: <1518461124-17371-1-git-send-email-sudeep.holla@arm.com> X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1592221938378679164?= X-GMAIL-MSGID: =?utf-8?q?1592221938378679164?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 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 diff --git a/MAINTAINERS b/MAINTAINERS index 7cede6e7dfed..d6e9e3eae5ac 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -13384,7 +13384,7 @@ 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 98ce9fc6e6c0..7ae23b25b406 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 71ec41e6364f..6605513eaa94 100644 --- a/drivers/clk/Makefile +++ b/drivers/clk/Makefile @@ -41,6 +41,7 @@ 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"); -- 2.7.4