Re: [PATCH 2/2] clk: meson-axg: Add AO Clock and Reset controller driver
From: Jerome Brunet
Date: Mon Feb 12 2018 - 10:32:59 EST
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@xxxxxxxxxxx>
> Signed-off-by: Yixun Lan <yixun.lan@xxxxxxxxxxx>
> ---
> 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.
> + *
> + * Copyright (c) 2016 Baylibre SAS.
> + * Author: Michael Turquette <mturquette@xxxxxxxxxxxx>
> + *
> + * Copyright (c) 2018 Amlogic, inc.
> + * Author: Qiufang Dai <qiufang.dai@xxxxxxxxxxx>
> + */
> +#include <linux/clk-provider.h>
> +#include <linux/of_address.h>
I did not see what is requiring this header. Did I miss something ?
> +#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.
> +#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.
> +#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.
> +
> +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 ?
* 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.
> + }, \
> +}
> +
> +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.
> +
> +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.
> + },
> +};
> +
> +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
> +};
> +
> +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@xxxxxxxxxxxx>
> + *
> + * Copyright (c) 2018 Amlogic, inc.
> + * Author: Qiufang Dai <qiufang.dai@xxxxxxxxxxx>
> + */
> +
> +#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.
> +
> +#endif /* __AXG_AOCLKC_H */