[PATCH 2/2] clk: meson-axg: Add AO Clock and Reset controller driver

Yixun Lan yixun.lan at amlogic.com
Fri Mar 23 07:13:31 PDT 2018


Hi Jerome:


On 02/12/2018 11:32 PM, Jerome Brunet wrote:
> On Fri, 2018-02-09 at 15:00 +0800, Yixun Lan wrote:
>> Adds a Clock and Reset controller driver for the Always-On part
>> of the Amlogic Meson-AXG SoC.
>>
>> Signed-off-by: Qiufang Dai <qiufang.dai at amlogic.com>
>> Signed-off-by: Yixun Lan <yixun.lan at amlogic.com>
>> ---
>>  drivers/clk/meson/Makefile    |   2 +-
>>  drivers/clk/meson/axg-aoclk.c | 236 ++++++++++++++++++++++++++++++++++++++++++
>>  drivers/clk/meson/axg-aoclk.h |  25 +++++
>>  3 files changed, 262 insertions(+), 1 deletion(-)
>>  create mode 100644 drivers/clk/meson/axg-aoclk.c
>>  create mode 100644 drivers/clk/meson/axg-aoclk.h
>>
>> diff --git a/drivers/clk/meson/Makefile b/drivers/clk/meson/Makefile
>> index 11f99139b844..c7510744406a 100644
>> --- a/drivers/clk/meson/Makefile
>> +++ b/drivers/clk/meson/Makefile
>> @@ -6,6 +6,6 @@ obj-$(CONFIG_COMMON_CLK_AMLOGIC) += clk-pll.o clk-mpll.o clk-audio-divider.o
>>  obj-$(CONFIG_COMMON_CLK_AMLOGIC) += clk-phase.o
>>  obj-$(CONFIG_COMMON_CLK_MESON8B) += meson8b.o
>>  obj-$(CONFIG_COMMON_CLK_GXBB)	 += gxbb.o gxbb-aoclk.o gxbb-aoclk-32k.o
>> -obj-$(CONFIG_COMMON_CLK_AXG)	 += axg.o
>> +obj-$(CONFIG_COMMON_CLK_AXG)	 += axg.o axg-aoclk.o
>>  obj-$(CONFIG_COMMON_CLK_AXG_AUDIO)	+= axg-audio.o
>>  obj-$(CONFIG_COMMON_CLK_REGMAP_MESON)	+= clk-regmap.o
>> diff --git a/drivers/clk/meson/axg-aoclk.c b/drivers/clk/meson/axg-aoclk.c
>> new file mode 100644
>> index 000000000000..832aa19dd76c
>> --- /dev/null
>> +++ b/drivers/clk/meson/axg-aoclk.c
>> @@ -0,0 +1,236 @@
>> +// SPDX-License-Identifier: GPL-2.0+
>> +/*
>> + * AmLogic Meson-AXG Clock Controller Driver
> 
> Unless there a rule behind it, I think we should stop 
> with the funny camel case and stick to "Amlogic" like written below.
> 
will fix it

>> + *
>> + * Copyright (c) 2016 Baylibre SAS.
>> + * Author: Michael Turquette <mturquette at baylibre.com>
>> + *
>> + * Copyright (c) 2018 Amlogic, inc.
>> + * Author: Qiufang Dai <qiufang.dai at amlogic.com>
>> + */
>> +#include <linux/clk-provider.h>
>> +#include <linux/of_address.h>
> I did not see what is requiring this header. Did I miss something ?
> 
will drop this
>> +#include <linux/platform_device.h>
>> +#include <linux/reset-controller.h>
>> +#include <linux/mfd/syscon.h>
>> +#include <linux/regmap.h>
>> +#include <linux/init.h>
>> +#include <linux/delay.h>
> Same question for this one.
> 
ditto

>> +#include <dt-bindings/clock/axg-aoclkc.h>
>> +#include <dt-bindings/reset/axg-aoclkc.h>
> 
> I think those should be included in the same fashion as axg.h, gxbb.h and
> meson8.h ... which is at the end of the private header.
> 
will do

>> +#include "clkc.h"
>> +#include "axg-aoclk.h"
>> +
>> +struct axg_aoclk_reset_controller {
>> +	struct reset_controller_dev reset;
>> +	unsigned int *data;
>> +	struct regmap *regmap;
>> +};
> 
> This duplicate what is gxbb-aoclk.
> Please make something cleaner with a shared definition.
> 
as you already raised this in another email.
and I will factor the common code, and send out an updated version
>> +
>> +static int axg_aoclk_do_reset(struct reset_controller_dev *rcdev,
>> +			       unsigned long id)
>> +{
>> +	struct axg_aoclk_reset_controller *reset =
>> +		container_of(rcdev, struct axg_aoclk_reset_controller, reset);
>> +
>> +	return regmap_write(reset->regmap, AO_RTI_GEN_CNTL_REG0,
>> +			    BIT(reset->data[id]));
>> +}
>> +
>> +static const struct reset_control_ops axg_aoclk_reset_ops = {
>> +	.reset = axg_aoclk_do_reset,
>> +};
>> +
>> +#define AXG_AO_GATE(_name, _bit)					\
>> +static struct clk_regmap _name##_ao = {					\
>> +	.data = &(struct clk_regmap_gate_data) {			\
>> +		.offset = (AO_RTI_GEN_CNTL_REG0),			\
>> +		.bit_idx = (_bit),					\
>> +	},								\
>> +	.hw.init = &(struct clk_init_data) {				\
>> +		.name = #_name "_ao",					\
>> +		.ops = &clk_regmap_gate_ops,				\
>> +		.parent_names = (const char *[]){ "clk81" },		\
>> +		.num_parents = 1,					\
>> +		.flags = (CLK_SET_RATE_PARENT | CLK_IGNORE_UNUSED),	\
> 
> These clock are peripheral clocks (meant to enable/disable IPs):
> * CLK_SET_RATE_PARENT: why do you need rate propagation here ? do you really
> want a consumer of these gate to be able to change clk81 ? 
> 

No, we shouldn't change clk81, will drop this flag

> * CLK_IGNORE_UNUSED: Why do need this flag ? All the IPs behind this
> definition should be able to claim the pclk properly. If not the driver should
> be fixed.
> 
not really, we could drop this flag

but I'd like to address this in yet another thread (rather than in this
"add ao clock and reset driver")

>> +	},								\
>> +}
>> +
>> +AXG_AO_GATE(remote, 0);
>> +AXG_AO_GATE(i2c_master, 1);
>> +AXG_AO_GATE(i2c_slave, 2);
>> +AXG_AO_GATE(uart1, 3);
>> +AXG_AO_GATE(uart2, 5);
>> +AXG_AO_GATE(ir_blaster, 6);
>> +AXG_AO_GATE(saradc, 7);
>> +
>> +static struct clk_fixed_rate ao_alt_xtal = {
>> +	.fixed_rate = 32000,
>> +	.hw.init = &(struct clk_init_data){
>> +		.name = "ao_alt_xtal",
>> +		.num_parents = 0,
>> +		.ops = &clk_fixed_rate_ops,
>> +	},
>> +};
> 
> Unless this xtal is actually embedded in SoC, this should be defined it the DT,
> same as the other xtal.
> 
it's an external crystal, I will put it into DT file, thanks for hint

>> +
>> +static struct clk_regmap ao_clk81 = {
>> +	.data = &(struct clk_regmap_mux_data) {
>> +		.offset = AO_RTI_PWR_CNTL_REG0,
>> +		.mask = 0x1,
>> +		.shift = 8,
>> +	},
>> +	.hw.init = &(struct clk_init_data){
>> +		.name = "ao_clk81",
>> +		.ops = &clk_regmap_mux_ro_ops,
>> +		.parent_names = (const char *[]){ "clk81", "ao_alt_xtal"},
>> +		.num_parents = 2,
>> +	},
>> +};
>> +
>> +static struct clk_regmap axg_saradc_mux = {
>> +	.data = &(struct clk_regmap_mux_data) {
>> +		.offset = AO_SAR_CLK,
>> +		.mask = 0x3,
>> +		.shift = 9,
>> +	},
>> +	.hw.init = &(struct clk_init_data){
>> +		.name = "axg_saradc_mux",
>> +		.ops = &clk_regmap_mux_ops,
>> +		.parent_names = (const char *[]){ "xtal", "ao_clk81" },
>> +		.num_parents = 2,
>> +	},
>> +};
>> +
>> +static struct clk_regmap axg_saradc_div = {
>> +	.data = &(struct clk_regmap_div_data) {
>> +		.offset = AO_SAR_CLK,
>> +		.shift = 0,
>> +		.width = 8,
>> +	},
>> +	.hw.init = &(struct clk_init_data){
>> +		.name = "axg_saradc_div",
>> +		.ops = &clk_regmap_divider_ops,
>> +		.parent_names = (const char *[]){ "axg_saradc_mux" },
>> +		.num_parents = 1,
> 
> Should the saradc mux change to accomodate the requested rate, if needed ?
> If so, you might want to add a CLK_SET_RATE_PARENT here.
> 
yes, from hardware perspective, the mux can select clk parent, I will
update this

>> +	},
>> +};
>> +
>> +static struct clk_regmap axg_saradc_gate = {
>> +	.data = &(struct clk_regmap_gate_data) {
>> +		.offset = AO_SAR_CLK,
>> +		.bit_idx = 8,
>> +	},
>> +	.hw.init = &(struct clk_init_data){
>> +		.name = "axg_saradc_gate",
>> +		.ops = &clk_regmap_gate_ops,
>> +		.parent_names = (const char *[]){ "axg_saradc_div" },
>> +		.num_parents = 1,
>> +		.flags = CLK_SET_RATE_PARENT,
>> +	},
>> +};
>> +
>> +static unsigned int axg_aoclk_reset[] = {
>> +	[RESET_AO_REMOTE] = 16,
>> +	[RESET_AO_I2C_MASTER] = 18,
>> +	[RESET_AO_I2C_SLAVE] = 19,
>> +	[RESET_AO_UART1] = 17,
>> +	[RESET_AO_UART2] = 22,
>> +	[RESET_AO_IR_BLASTER] = 23,
>> +};
>> +
>> +static struct clk_regmap *axg_aoclk_regmap[] = {
>> +	[CLKID_AO_REMOTE]	= &remote_ao,
>> +	[CLKID_AO_I2C_MASTER]	= &i2c_master_ao,
>> +	[CLKID_AO_I2C_SLAVE]	= &i2c_slave_ao,
>> +	[CLKID_AO_UART1]	= &uart1_ao,
>> +	[CLKID_AO_UART2]	= &uart2_ao,
>> +	[CLKID_AO_IR_BLASTER]	= &ir_blaster_ao,
>> +	[CLKID_AO_SAR_ADC]	= &saradc_ao,
>> +	[CLKID_AO_CLK81]	= &ao_clk81,
>> +	[CLKID_AO_SAR_ADC_SEL]	= &axg_saradc_mux,
>> +	[CLKID_AO_SAR_ADC_DIV]	= &axg_saradc_div,
>> +	[CLKID_AO_SAR_ADC_CLK]	= &axg_saradc_gate,
>> +};
>> +
>> +static struct clk_hw_onecell_data axg_aoclk_onecell_data = {
>> +	.hws = {
>> +		[CLKID_AO_REMOTE]	= &remote_ao.hw,
>> +		[CLKID_AO_I2C_MASTER]	= &i2c_master_ao.hw,
>> +		[CLKID_AO_I2C_SLAVE]	= &i2c_slave_ao.hw,
>> +		[CLKID_AO_UART1]	= &uart1_ao.hw,
>> +		[CLKID_AO_UART2]	= &uart2_ao.hw,
>> +		[CLKID_AO_IR_BLASTER]	= &ir_blaster_ao.hw,
>> +		[CLKID_AO_SAR_ADC]	= &saradc_ao.hw,
>> +		[CLKID_AO_CLK81]	= &ao_clk81.hw,
>> +		[CLKID_AO_SAR_ADC_SEL]	= &axg_saradc_mux.hw,
>> +		[CLKID_AO_SAR_ADC_DIV]	= &axg_saradc_div.hw,
>> +		[CLKID_AO_SAR_ADC_CLK]	= &axg_saradc_gate.hw,
>> +		[CLKID_AO_ALT_XTAL]	= &ao_alt_xtal.hw,
>> +	},
>> +	.num = 12,
> 
> I would prefer having a NR_CLKS defined in drivers/clk/meson/axg-aoclk.h
> 
can do

>> +};
>> +
>> +static int axg_aoclkc_probe(struct platform_device *pdev)
>> +{
>> +	struct axg_aoclk_reset_controller *rstc;
>> +	struct device *dev = &pdev->dev;
>> +	struct regmap *regmap;
>> +	int ret, clkid;
>> +
>> +	rstc = devm_kzalloc(dev, sizeof(*rstc), GFP_KERNEL);
>> +	if (!rstc)
>> +		return -ENOMEM;
>> +
>> +	regmap = syscon_node_to_regmap(of_get_parent(dev->of_node));
>> +	if (IS_ERR(regmap)) {
>> +		dev_err(dev, "failed to get regmap\n");
>> +		return -ENODEV;
>> +	}
>> +
>> +	/* Reset Controller */
>> +	rstc->regmap = regmap;
>> +	rstc->data = axg_aoclk_reset;
>> +	rstc->reset.ops = &axg_aoclk_reset_ops;
>> +	rstc->reset.nr_resets = ARRAY_SIZE(axg_aoclk_reset);
>> +	rstc->reset.of_node = dev->of_node;
>> +	ret = devm_reset_controller_register(dev, &rstc->reset);
>> +
>> +	/*
>> +	 * Populate regmap and register all clks
>> +	 */
>> +	for (clkid = 0; clkid < ARRAY_SIZE(axg_aoclk_regmap); clkid++) {
>> +		axg_aoclk_regmap[clkid]->map = regmap;
>> +
>> +		ret = devm_clk_hw_register(dev,
>> +					axg_aoclk_onecell_data.hws[clkid]);
>> +		if (ret) {
>> +			dev_err(dev, "clk register failed.\n");
>> +			return ret;
>> +		}
>> +	}
>> +
>> +	/* Specific clocks */
>> +	ret = devm_clk_hw_register(dev, &ao_alt_xtal.hw);
>> +	if (ret) {
>> +		dev_err(dev, "clk alt_xtal register failed.\n");
>> +		return ret;
>> +	}
>> +
>> +	return of_clk_add_hw_provider(dev->of_node, of_clk_hw_onecell_get,
>> +			&axg_aoclk_onecell_data);
>> +}
>> +
>> +static const struct of_device_id axg_aoclkc_match_table[] = {
>> +	{ .compatible = "amlogic,meson-axg-aoclkc" },
>> +	{ }
>> +};
>> +
>> +static struct platform_driver axg_aoclkc_driver = {
>> +	.probe		= axg_aoclkc_probe,
>> +	.driver		= {
>> +		.name	= "axg-aoclkc",
>> +		.of_match_table = axg_aoclkc_match_table,
>> +	},
>> +};
>> +
>> +builtin_platform_driver(axg_aoclkc_driver);
>> diff --git a/drivers/clk/meson/axg-aoclk.h b/drivers/clk/meson/axg-aoclk.h
>> new file mode 100644
>> index 000000000000..70f82004d3db
>> --- /dev/null
>> +++ b/drivers/clk/meson/axg-aoclk.h
>> @@ -0,0 +1,25 @@
>> +/* SPDX-License-Identifier: (GPL-2.0+ OR MIT) */
>> +/*
>> + * Copyright (c) 2017 BayLibre, SAS
>> + * Author: Neil Armstrong <narmstrong at baylibre.com>
>> + *
>> + * Copyright (c) 2018 Amlogic, inc.
>> + * Author: Qiufang Dai <qiufang.dai at amlogic.com>
>> + */
>> +
>> +#ifndef __AXG_AOCLKC_H
>> +#define __AXG_AOCLKC_H
>> +
>> +/* AO Configuration Clock registers offsets
>> + * Register offsets from the data sheet must be multiplied by 4.
>> + */
>> +#define AO_RTI_PWR_CNTL_REG1	(0x03 << 2)
>> +#define AO_RTI_PWR_CNTL_REG0	(0x04 << 2)
>> +#define AO_RTI_GEN_CNTL_REG0	(0x10 << 2)
>> +#define AO_OSCIN_CNTL		(0x16 << 2)
>> +#define AO_CRT_CLK_CNTL1	(0x1a << 2)
>> +#define AO_SAR_CLK		(0x24 << 2)
>> +#define AO_RTC_ALT_CLK_CNTL0	(0x25 << 2)
>> +#define AO_RTC_ALT_CLK_CNTL1	(0x26 << 2)
> 
> As already pointed out for the axg clk series, please remove those
> calculation from the header file.
> 
Ok, will update
>> +
>> +#endif /* __AXG_AOCLKC_H */
> 
> .
> 




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