From 81ac38847a1d7fdd74a232cae195ff8f0fb4ab21 Mon Sep 17 00:00:00 2001 From: Georgi Djakov Date: Tue, 5 Dec 2017 17:47:01 +0200 Subject: clk: qcom: Add APCS clock controller support Add a driver for the APCS clock controller. It is part of the APCS hardware block, which among other things implements also a combined mux and half integer divider functionality. It can choose between a fixed-rate clock or the dedicated APCS (A53) PLL. The source and the divider can be set both at the same time. This is required for enabling CPU frequency scaling on MSM8916-based platforms. Signed-off-by: Georgi Djakov Acked-by: Bjorn Andersson Tested-by: Amit Kucheria [sboyd@codeaurora.org: Include rcg header for parent_map, drop multiple unneeded includes, add COMPILE_TEST to APCS depends, made tristate/modular] Signed-off-by: Stephen Boyd --- drivers/clk/qcom/Kconfig | 11 ++++ drivers/clk/qcom/Makefile | 1 + drivers/clk/qcom/apcs-msm8916.c | 138 ++++++++++++++++++++++++++++++++++++++++ 3 files changed, 150 insertions(+) create mode 100644 drivers/clk/qcom/apcs-msm8916.c (limited to 'drivers') diff --git a/drivers/clk/qcom/Kconfig b/drivers/clk/qcom/Kconfig index 49db9fda6548..769e27353e1b 100644 --- a/drivers/clk/qcom/Kconfig +++ b/drivers/clk/qcom/Kconfig @@ -22,6 +22,17 @@ config QCOM_A53PLL Say Y if you want to support higher CPU frequencies on MSM8916 devices. +config QCOM_CLK_APCS_MSM8916 + tristate "MSM8916 APCS Clock Controller" + depends on COMMON_CLK_QCOM + depends on QCOM_APCS_IPC || COMPILE_TEST + default ARCH_QCOM + help + Support for the APCS Clock Controller on msm8916 devices. The + APCS is managing the mux and divider which feeds the CPUs. + Say Y if you want to support CPU frequency scaling on devices + such as msm8916. + config QCOM_CLK_RPM tristate "RPM based Clock Controller" depends on COMMON_CLK_QCOM && MFD_QCOM_RPM diff --git a/drivers/clk/qcom/Makefile b/drivers/clk/qcom/Makefile index 7c51d877f967..0408cebf38d4 100644 --- a/drivers/clk/qcom/Makefile +++ b/drivers/clk/qcom/Makefile @@ -34,5 +34,6 @@ obj-$(CONFIG_MSM_MMCC_8960) += mmcc-msm8960.o obj-$(CONFIG_MSM_MMCC_8974) += mmcc-msm8974.o obj-$(CONFIG_MSM_MMCC_8996) += mmcc-msm8996.o obj-$(CONFIG_QCOM_A53PLL) += a53-pll.o +obj-$(CONFIG_QCOM_CLK_APCS_MSM8916) += apcs-msm8916.o obj-$(CONFIG_QCOM_CLK_RPM) += clk-rpm.o obj-$(CONFIG_QCOM_CLK_SMD_RPM) += clk-smd-rpm.o diff --git a/drivers/clk/qcom/apcs-msm8916.c b/drivers/clk/qcom/apcs-msm8916.c new file mode 100644 index 000000000000..246957f1a413 --- /dev/null +++ b/drivers/clk/qcom/apcs-msm8916.c @@ -0,0 +1,138 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Qualcomm APCS clock controller driver + * + * Copyright (c) 2017, Linaro Limited + * Author: Georgi Djakov + */ + +#include +#include +#include +#include +#include +#include +#include + +#include "clk-regmap.h" +#include "clk-regmap-mux-div.h" + +static const u32 gpll0_a53cc_map[] = { 4, 5 }; + +static const char * const gpll0_a53cc[] = { + "gpll0_vote", + "a53pll", +}; + +/* + * We use the notifier function for switching to a temporary safe configuration + * (mux and divider), while the A53 PLL is reconfigured. + */ +static int a53cc_notifier_cb(struct notifier_block *nb, unsigned long event, + void *data) +{ + int ret = 0; + struct clk_regmap_mux_div *md = container_of(nb, + struct clk_regmap_mux_div, + clk_nb); + if (event == PRE_RATE_CHANGE) + /* set the mux and divider to safe frequency (400mhz) */ + ret = mux_div_set_src_div(md, 4, 3); + + return notifier_from_errno(ret); +} + +static int qcom_apcs_msm8916_clk_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct device *parent = dev->parent; + struct clk_regmap_mux_div *a53cc; + struct regmap *regmap; + struct clk_init_data init = { }; + int ret; + + regmap = dev_get_regmap(parent, NULL); + if (IS_ERR(regmap)) { + ret = PTR_ERR(regmap); + dev_err(dev, "failed to get regmap: %d\n", ret); + return ret; + } + + a53cc = devm_kzalloc(dev, sizeof(*a53cc), GFP_KERNEL); + if (!a53cc) + return -ENOMEM; + + init.name = "a53mux"; + init.parent_names = gpll0_a53cc; + init.num_parents = ARRAY_SIZE(gpll0_a53cc); + init.ops = &clk_regmap_mux_div_ops; + init.flags = CLK_SET_RATE_PARENT; + + a53cc->clkr.hw.init = &init; + a53cc->clkr.regmap = regmap; + a53cc->reg_offset = 0x50; + a53cc->hid_width = 5; + a53cc->hid_shift = 0; + a53cc->src_width = 3; + a53cc->src_shift = 8; + a53cc->parent_map = gpll0_a53cc_map; + + a53cc->pclk = devm_clk_get(parent, NULL); + if (IS_ERR(a53cc->pclk)) { + ret = PTR_ERR(a53cc->pclk); + dev_err(dev, "failed to get clk: %d\n", ret); + return ret; + } + + a53cc->clk_nb.notifier_call = a53cc_notifier_cb; + ret = clk_notifier_register(a53cc->pclk, &a53cc->clk_nb); + if (ret) { + dev_err(dev, "failed to register clock notifier: %d\n", ret); + return ret; + } + + ret = devm_clk_register_regmap(dev, &a53cc->clkr); + if (ret) { + dev_err(dev, "failed to register regmap clock: %d\n", ret); + goto err; + } + + ret = of_clk_add_hw_provider(parent->of_node, of_clk_hw_simple_get, + &a53cc->clkr.hw); + if (ret) { + dev_err(dev, "failed to add clock provider: %d\n", ret); + goto err; + } + + platform_set_drvdata(pdev, a53cc); + + return 0; + +err: + clk_notifier_unregister(a53cc->pclk, &a53cc->clk_nb); + return ret; +} + +static int qcom_apcs_msm8916_clk_remove(struct platform_device *pdev) +{ + struct clk_regmap_mux_div *a53cc = platform_get_drvdata(pdev); + struct device *parent = pdev->dev.parent; + + clk_notifier_unregister(a53cc->pclk, &a53cc->clk_nb); + of_clk_del_provider(parent->of_node); + + return 0; +} + +static struct platform_driver qcom_apcs_msm8916_clk_driver = { + .probe = qcom_apcs_msm8916_clk_probe, + .remove = qcom_apcs_msm8916_clk_remove, + .driver = { + .name = "qcom-apcs-msm8916-clk", + }, +}; +module_platform_driver(qcom_apcs_msm8916_clk_driver); + +MODULE_AUTHOR("Georgi Djakov "); +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("Qualcomm MSM8916 APCS clock driver"); -- cgit v1.2.3