diff mbox

[v4,09/12] clk: qcom: Add Krait clock controller driver

Message ID 1512725401-4944-10-git-send-email-sricharan@codeaurora.org (mailing list archive)
State Not Applicable, archived
Delegated to: Andy Gross
Headers show

Commit Message

Sricharan Ramabadhran Dec. 8, 2017, 9:29 a.m. UTC
From: Stephen Boyd <sboyd@codeaurora.org>

The Krait CPU clocks are made up of a primary mux and secondary
mux for each CPU and the L2, controlled via cp15 accessors. For
Kraits within KPSSv1 each secondary mux accepts a different aux
source, but on KPSSv2 each secondary mux accepts the same aux
source.

Cc: <devicetree@vger.kernel.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
---
 .../devicetree/bindings/clock/qcom,krait-cc.txt    |  22 ++
 drivers/clk/qcom/Kconfig                           |   8 +
 drivers/clk/qcom/Makefile                          |   1 +
 drivers/clk/qcom/krait-cc.c                        | 350 +++++++++++++++++++++
 4 files changed, 381 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/clock/qcom,krait-cc.txt
 create mode 100644 drivers/clk/qcom/krait-cc.c

Comments

Philippe Ombredanne Dec. 8, 2017, 10:23 a.m. UTC | #1
Sricharan, Stephen,

On Fri, Dec 8, 2017 at 10:29 AM, Sricharan R <sricharan@codeaurora.org> wrote:
> From: Stephen Boyd <sboyd@codeaurora.org>
>
> The Krait CPU clocks are made up of a primary mux and secondary
> mux for each CPU and the L2, controlled via cp15 accessors. For
> Kraits within KPSSv1 each secondary mux accepts a different aux
> source, but on KPSSv2 each secondary mux accepts the same aux
> source.
>
> Cc: <devicetree@vger.kernel.org>
> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
[]
> --- /dev/null
> +++ b/drivers/clk/qcom/krait-cc.c
> @@ -0,0 +1,350 @@
> +/* Copyright (c) 2013-2015, The Linux Foundation. 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 and
> + * only 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.
> + */

Have you considered using the new SPDX ids? Something like this:

// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2013-2015, The Linux Foundation. All rights reserved.

Beside  being simpler and increasing the code to comment ratio by
deleting 9 lines of boilerplate, this will also save a few trees over
the long term each time that I print the source code of the kernel ;)
(do not worry, I am NOT as insane as to really print the kernel
sources, but someone more insane than me may well do it)

You may wonder about the C++ // comment style I used here... Please
see Linus posts on the topic as well as Thomas doc patches overall for
instructions on using the SPDX ids.

And if you were to do this for your past, present and future
contributions (eventually these of your group), I would be quite
grateful.

Thank you for your kind consideration
Sricharan Ramabadhran Dec. 8, 2017, 11 a.m. UTC | #2
Hi Philippe,


On 12/8/2017 3:53 PM, Philippe Ombredanne wrote:
> Sricharan, Stephen,
> 
> On Fri, Dec 8, 2017 at 10:29 AM, Sricharan R <sricharan@codeaurora.org> wrote:
>> From: Stephen Boyd <sboyd@codeaurora.org>
>>
>> The Krait CPU clocks are made up of a primary mux and secondary
>> mux for each CPU and the L2, controlled via cp15 accessors. For
>> Kraits within KPSSv1 each secondary mux accepts a different aux
>> source, but on KPSSv2 each secondary mux accepts the same aux
>> source.
>>
>> Cc: <devicetree@vger.kernel.org>
>> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
> []
>> --- /dev/null
>> +++ b/drivers/clk/qcom/krait-cc.c
>> @@ -0,0 +1,350 @@
>> +/* Copyright (c) 2013-2015, The Linux Foundation. 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 and
>> + * only 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.
>> + */
> 
> Have you considered using the new SPDX ids? Something like this:
> 
> // SPDX-License-Identifier: GPL-2.0
> // Copyright (c) 2013-2015, The Linux Foundation. All rights reserved.
> 
> Beside  being simpler and increasing the code to comment ratio by
> deleting 9 lines of boilerplate, this will also save a few trees over
> the long term each time that I print the source code of the kernel ;)
> (do not worry, I am NOT as insane as to really print the kernel
> sources, but someone more insane than me may well do it)
> 
> You may wonder about the C++ // comment style I used here... Please
> see Linus posts on the topic as well as Thomas doc patches overall for
> instructions on using the SPDX ids.
> 
> And if you were to do this for your past, present and future
> contributions (eventually these of your group), I would be quite
> grateful.
> 
> Thank you for your kind consideration
> 

Ha ok. will change it to use this one. Infact saw this feedback on other
patches, but missed updating to it while sending.

Regards,
 Sricharan
Philippe Ombredanne Dec. 8, 2017, 1:10 p.m. UTC | #3
Sricharan,

On Fri, Dec 8, 2017 at 12:00 PM, Sricharan R <sricharan@codeaurora.org> wrote:
> Hi Philippe,
>
>
> On 12/8/2017 3:53 PM, Philippe Ombredanne wrote:
>> Sricharan, Stephen,
>>
>> On Fri, Dec 8, 2017 at 10:29 AM, Sricharan R <sricharan@codeaurora.org> wrote:
>>> From: Stephen Boyd <sboyd@codeaurora.org>
>>>
>>> The Krait CPU clocks are made up of a primary mux and secondary
>>> mux for each CPU and the L2, controlled via cp15 accessors. For
>>> Kraits within KPSSv1 each secondary mux accepts a different aux
>>> source, but on KPSSv2 each secondary mux accepts the same aux
>>> source.
>>>
>>> Cc: <devicetree@vger.kernel.org>
>>> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
>> []
>>> --- /dev/null
>>> +++ b/drivers/clk/qcom/krait-cc.c
>>> @@ -0,0 +1,350 @@
>>> +/* Copyright (c) 2013-2015, The Linux Foundation. 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 and
>>> + * only 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.
>>> + */
>>
>> Have you considered using the new SPDX ids? Something like this:
>>
>> // SPDX-License-Identifier: GPL-2.0
>> // Copyright (c) 2013-2015, The Linux Foundation. All rights reserved.
>>
>> Beside  being simpler and increasing the code to comment ratio by
>> deleting 9 lines of boilerplate, this will also save a few trees over
>> the long term each time that I print the source code of the kernel ;)
>> (do not worry, I am NOT as insane as to really print the kernel
>> sources, but someone more insane than me may well do it)
>>
>> You may wonder about the C++ // comment style I used here... Please
>> see Linus posts on the topic as well as Thomas doc patches overall for
>> instructions on using the SPDX ids.
>>
>> And if you were to do this for your past, present and future
>> contributions (eventually these of your group), I would be quite
>> grateful.
>>
>> Thank you for your kind consideration
>>
>
> Ha ok. will change it to use this one. Infact saw this feedback on other
> patches, but missed updating to it while sending.

Thanks!
diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/clock/qcom,krait-cc.txt b/Documentation/devicetree/bindings/clock/qcom,krait-cc.txt
new file mode 100644
index 0000000..874138f
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/qcom,krait-cc.txt
@@ -0,0 +1,22 @@ 
+Krait Clock Controller
+
+PROPERTIES
+
+- compatible:
+	Usage: required
+	Value type: <string>
+	Definition: must be one of:
+			"qcom,krait-cc-v1"
+			"qcom,krait-cc-v2"
+
+- #clock-cells:
+	Usage: required
+	Value type: <u32>
+	Definition: must be 1
+
+Example:
+
+	kraitcc: clock-controller {
+		compatible = "qcom,krait-cc-v1";
+		#clock-cells = <1>;
+	};
diff --git a/drivers/clk/qcom/Kconfig b/drivers/clk/qcom/Kconfig
index 17dcb88..de6b60d 100644
--- a/drivers/clk/qcom/Kconfig
+++ b/drivers/clk/qcom/Kconfig
@@ -222,6 +222,14 @@  config KPSS_XCC
 	  if you want to support CPU frequency scaling on devices such
 	  as MSM8960, APQ8064, etc.
 
+config KRAITCC
+	tristate "Krait Clock Controller"
+	depends on COMMON_CLK_QCOM && ARM
+	select KRAIT_CLOCKS
+	help
+	  Support for the Krait CPU clocks on Qualcomm devices.
+	  Say Y if you want to support CPU frequency scaling.
+
 config KRAIT_CLOCKS
 	bool
 	select KRAIT_L2_ACCESSORS
diff --git a/drivers/clk/qcom/Makefile b/drivers/clk/qcom/Makefile
index 7ad2302..6e6c700 100644
--- a/drivers/clk/qcom/Makefile
+++ b/drivers/clk/qcom/Makefile
@@ -39,3 +39,4 @@  obj-$(CONFIG_QCOM_CLK_SMD_RPM) += clk-smd-rpm.o
 obj-$(CONFIG_SPMI_PMIC_CLKDIV) += clk-spmi-pmic-div.o
 obj-$(CONFIG_KPSS_XCC) += kpss-xcc.o
 obj-$(CONFIG_QCOM_HFPLL) += hfpll.o
+obj-$(CONFIG_KRAITCC) += krait-cc.o
diff --git a/drivers/clk/qcom/krait-cc.c b/drivers/clk/qcom/krait-cc.c
new file mode 100644
index 0000000..f5ffb1a
--- /dev/null
+++ b/drivers/clk/qcom/krait-cc.c
@@ -0,0 +1,350 @@ 
+/* Copyright (c) 2013-2015, The Linux Foundation. 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 and
+ * only 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 <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/slab.h>
+
+#include "clk-krait.h"
+
+static unsigned int sec_mux_map[] = {
+	2,
+	0,
+};
+
+static unsigned int pri_mux_map[] = {
+	1,
+	2,
+	0,
+};
+
+static int
+krait_add_div(struct device *dev, int id, const char *s, unsigned int offset)
+{
+	struct krait_div2_clk *div;
+	struct clk_init_data init = {
+		.num_parents = 1,
+		.ops = &krait_div2_clk_ops,
+		.flags = CLK_SET_RATE_PARENT,
+	};
+	const char *p_names[1];
+	struct clk *clk;
+
+	div = devm_kzalloc(dev, sizeof(*div), GFP_KERNEL);
+	if (!div)
+		return -ENOMEM;
+
+	div->width = 2;
+	div->shift = 6;
+	div->lpl = id >= 0;
+	div->offset = offset;
+	div->hw.init = &init;
+
+	init.name = kasprintf(GFP_KERNEL, "hfpll%s_div", s);
+	if (!init.name)
+		return -ENOMEM;
+
+	init.parent_names = p_names;
+	p_names[0] = kasprintf(GFP_KERNEL, "hfpll%s", s);
+	if (!p_names[0]) {
+		kfree(init.name);
+		return -ENOMEM;
+	}
+
+	clk = devm_clk_register(dev, &div->hw);
+	kfree(p_names[0]);
+	kfree(init.name);
+
+	return PTR_ERR_OR_ZERO(clk);
+}
+
+static int
+krait_add_sec_mux(struct device *dev, int id, const char *s,
+		  unsigned int offset, bool unique_aux)
+{
+	struct krait_mux_clk *mux;
+	static const char *sec_mux_list[] = {
+		"acpu_aux",
+		"qsb",
+	};
+	struct clk_init_data init = {
+		.parent_names = sec_mux_list,
+		.num_parents = ARRAY_SIZE(sec_mux_list),
+		.ops = &krait_mux_clk_ops,
+		.flags = CLK_SET_RATE_PARENT,
+	};
+	struct clk *clk;
+
+	mux = devm_kzalloc(dev, sizeof(*mux), GFP_KERNEL);
+	if (!mux)
+		return -ENOMEM;
+
+	mux->offset = offset;
+	mux->lpl = id >= 0;
+	mux->mask = 0x3;
+	mux->shift = 2;
+	mux->parent_map = sec_mux_map;
+	mux->hw.init = &init;
+
+	init.name = kasprintf(GFP_KERNEL, "krait%s_sec_mux", s);
+	if (!init.name)
+		return -ENOMEM;
+
+	if (unique_aux) {
+		sec_mux_list[0] = kasprintf(GFP_KERNEL, "acpu%s_aux", s);
+		if (!sec_mux_list[0]) {
+			clk = ERR_PTR(-ENOMEM);
+			goto err_aux;
+		}
+	}
+
+	clk = devm_clk_register(dev, &mux->hw);
+
+	if (unique_aux)
+		kfree(sec_mux_list[0]);
+err_aux:
+	kfree(init.name);
+	return PTR_ERR_OR_ZERO(clk);
+}
+
+static struct clk *
+krait_add_pri_mux(struct device *dev, int id, const char *s,
+		  unsigned int offset)
+{
+	struct krait_mux_clk *mux;
+	const char *p_names[3];
+	struct clk_init_data init = {
+		.parent_names = p_names,
+		.num_parents = ARRAY_SIZE(p_names),
+		.ops = &krait_mux_clk_ops,
+		.flags = CLK_SET_RATE_PARENT,
+	};
+	struct clk *clk;
+
+	mux = devm_kzalloc(dev, sizeof(*mux), GFP_KERNEL);
+	if (!mux)
+		return ERR_PTR(-ENOMEM);
+
+	mux->mask = 0x3;
+	mux->shift = 0;
+	mux->offset = offset;
+	mux->lpl = id >= 0;
+	mux->parent_map = pri_mux_map;
+	mux->hw.init = &init;
+
+	init.name = kasprintf(GFP_KERNEL, "krait%s_pri_mux", s);
+	if (!init.name)
+		return ERR_PTR(-ENOMEM);
+
+	p_names[0] = kasprintf(GFP_KERNEL, "hfpll%s", s);
+	if (!p_names[0]) {
+		clk = ERR_PTR(-ENOMEM);
+		goto err_p0;
+	}
+
+	p_names[1] = kasprintf(GFP_KERNEL, "hfpll%s_div", s);
+	if (!p_names[1]) {
+		clk = ERR_PTR(-ENOMEM);
+		goto err_p1;
+	}
+
+	p_names[2] = kasprintf(GFP_KERNEL, "krait%s_sec_mux", s);
+	if (!p_names[2]) {
+		clk = ERR_PTR(-ENOMEM);
+		goto err_p2;
+	}
+
+	clk = devm_clk_register(dev, &mux->hw);
+
+	kfree(p_names[2]);
+err_p2:
+	kfree(p_names[1]);
+err_p1:
+	kfree(p_names[0]);
+err_p0:
+	kfree(init.name);
+	return clk;
+}
+
+/* id < 0 for L2, otherwise id == physical CPU number */
+static struct clk *krait_add_clks(struct device *dev, int id, bool unique_aux)
+{
+	int ret;
+	unsigned int offset;
+	void *p = NULL;
+	const char *s;
+	struct clk *clk;
+
+	if (id >= 0) {
+		offset = 0x4501 + (0x1000 * id);
+		s = p = kasprintf(GFP_KERNEL, "%d", id);
+		if (!s)
+			return ERR_PTR(-ENOMEM);
+	} else {
+		offset = 0x500;
+		s = "_l2";
+	}
+
+	ret = krait_add_div(dev, id, s, offset);
+	if (ret) {
+		clk = ERR_PTR(ret);
+		goto err;
+	}
+
+	ret = krait_add_sec_mux(dev, id, s, offset, unique_aux);
+	if (ret) {
+		clk = ERR_PTR(ret);
+		goto err;
+	}
+
+	clk = krait_add_pri_mux(dev, id, s, offset);
+err:
+	kfree(p);
+	return clk;
+}
+
+static struct clk *krait_of_get(struct of_phandle_args *clkspec, void *data)
+{
+	unsigned int idx = clkspec->args[0];
+	struct clk **clks = data;
+
+	if (idx >= 5) {
+		pr_err("%s: invalid clock index %d\n", __func__, idx);
+		return ERR_PTR(-EINVAL);
+	}
+
+	return clks[idx] ? : ERR_PTR(-ENODEV);
+}
+
+static const struct of_device_id krait_cc_match_table[] = {
+	{ .compatible = "qcom,krait-cc-v1", (void *)1UL },
+	{ .compatible = "qcom,krait-cc-v2" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, krait_cc_match_table);
+
+static int krait_cc_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	const struct of_device_id *id;
+	unsigned long cur_rate, aux_rate;
+	int cpu;
+	struct clk *clk;
+	struct clk **clks;
+	struct clk *l2_pri_mux_clk;
+
+	id = of_match_device(krait_cc_match_table, dev);
+	if (!id)
+		return -ENODEV;
+
+	/* Rate is 1 because 0 causes problems for __clk_mux_determine_rate */
+	clk = clk_register_fixed_rate(dev, "qsb", NULL, 0, 1);
+	if (IS_ERR(clk))
+		return PTR_ERR(clk);
+
+	if (!id->data) {
+		clk = clk_register_fixed_factor(dev, "acpu_aux",
+						"gpll0_vote", 0, 1, 2);
+		if (IS_ERR(clk))
+			return PTR_ERR(clk);
+	}
+
+	/* Krait configurations have at most 4 CPUs and one L2 */
+	clks = devm_kcalloc(dev, 5, sizeof(*clks), GFP_KERNEL);
+	if (!clks)
+		return -ENOMEM;
+
+	for_each_possible_cpu(cpu) {
+		clk = krait_add_clks(dev, cpu, id->data);
+		if (IS_ERR(clk))
+			return PTR_ERR(clk);
+		clks[cpu] = clk;
+	}
+
+	l2_pri_mux_clk = krait_add_clks(dev, -1, id->data);
+	if (IS_ERR(l2_pri_mux_clk))
+		return PTR_ERR(l2_pri_mux_clk);
+	clks[4] = l2_pri_mux_clk;
+
+	/*
+	 * We don't want the CPU or L2 clocks to be turned off at late init
+	 * if CPUFREQ or HOTPLUG configs are disabled. So, bump up the
+	 * refcount of these clocks. Any cpufreq/hotplug manager can assume
+	 * that the clocks have already been prepared and enabled by the time
+	 * they take over.
+	 */
+	for_each_online_cpu(cpu) {
+		clk_prepare_enable(l2_pri_mux_clk);
+		WARN(clk_prepare_enable(clks[cpu]),
+		     "Unable to turn on CPU%d clock", cpu);
+	}
+
+	/*
+	 * Force reinit of HFPLLs and muxes to overwrite any potential
+	 * incorrect configuration of HFPLLs and muxes by the bootloader.
+	 * While at it, also make sure the cores are running at known rates
+	 * and print the current rate.
+	 *
+	 * The clocks are set to aux clock rate first to make sure the
+	 * secondary mux is not sourcing off of QSB. The rate is then set to
+	 * two different rates to force a HFPLL reinit under all
+	 * circumstances.
+	 */
+	cur_rate = clk_get_rate(l2_pri_mux_clk);
+	aux_rate = 384000000;
+	if (cur_rate == 1) {
+		pr_info("L2 @ QSB rate. Forcing new rate.\n");
+		cur_rate = aux_rate;
+	}
+	clk_set_rate(l2_pri_mux_clk, aux_rate);
+	clk_set_rate(l2_pri_mux_clk, 2);
+	clk_set_rate(l2_pri_mux_clk, cur_rate);
+	pr_info("L2 @ %lu KHz\n", clk_get_rate(l2_pri_mux_clk) / 1000);
+	for_each_possible_cpu(cpu) {
+		clk = clks[cpu];
+		cur_rate = clk_get_rate(clk);
+		if (cur_rate == 1) {
+			pr_info("CPU%d @ QSB rate. Forcing new rate.\n", cpu);
+			cur_rate = aux_rate;
+		}
+
+		clk_set_rate(clk, aux_rate);
+		clk_set_rate(clk, 2);
+		clk_set_rate(clk, cur_rate);
+		pr_info("CPU%d @ %lu KHz\n", cpu, clk_get_rate(clk) / 1000);
+	}
+
+	of_clk_add_provider(dev->of_node, krait_of_get, clks);
+
+	return 0;
+}
+
+static struct platform_driver krait_cc_driver = {
+	.probe = krait_cc_probe,
+	.driver = {
+		.name = "krait-cc",
+		.of_match_table = krait_cc_match_table,
+	},
+};
+module_platform_driver(krait_cc_driver);
+
+MODULE_DESCRIPTION("Krait CPU Clock Driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:krait-cc");