Re: [PATCH 2/4] clk: samsung: Add a separate driver for Exynos4412 ISP clocks

[Krzysztof Kozlowski <krzk@kernel.org>]

On Mon, Oct 02, 2017 at 12:47:57PM +0200, Marek Szyprowski wrote:
> Some registers for the Exynos 4412 ISP (Camera subsystem) clocks are
> partially located in the SOC area, which belongs to ISP power domain.
> Because those registers are also located in a different memory region
> than the main clock controller, support for them can be provided by
> a separate clock controller. This in turn allows to almost seamlessly
> make it aware of the power domain using recently introduced runtime
> PM support for clocks.
> 
> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
> ---
>  .../devicetree/bindings/clock/exynos4-clock.txt    |  27 ++++
>  drivers/clk/samsung/Makefile                       |   1 +
>  drivers/clk/samsung/clk-exynos4412-isp.c           | 179 +++++++++++++++++++++
>  include/dt-bindings/clock/exynos4.h                |  35 ++++
>  4 files changed, 242 insertions(+)
>  create mode 100644 drivers/clk/samsung/clk-exynos4412-isp.c
> 
> diff --git a/Documentation/devicetree/bindings/clock/exynos4-clock.txt b/Documentation/devicetree/bindings/clock/exynos4-clock.txt
> index f5a5b19ed3b2..9b260e0d1e66 100644
> --- a/Documentation/devicetree/bindings/clock/exynos4-clock.txt
> +++ b/Documentation/devicetree/bindings/clock/exynos4-clock.txt
> @@ -41,3 +41,30 @@ Example 2: UART controller node that consumes the clock generated by the clock
>  		clocks = <&clock CLK_UART2>, <&clock CLK_SCLK_UART2>;
>  		clock-names = "uart", "clk_uart_baud0";
>  	};
> +
> +Exynos4412 SoC contains some additional clocks for FIMC-ISP (Camera ISP)
> +subsystem. Registers for those clocks are partially located in the SOC area,
> +which belongs to ISP power domain. Because those registers are also located
> +in a different memory region than the main clock controller, a separate clock
> +controller has to be defined for handling them. The compatible string to such
> +controller is "samsung,exynos4412-isp-clock". It also has two input clocks
> +from the main Exynos4412 clock controller: "aclk200" and "aclk400_mcuisp".
> +The ISP clock controller has to be linked with respective ISP power domain
> +(for more information, see Samsung Exynos power domains bindings).
> +
> +Example 3: An example of a clock controllers for Exynos4412 SoCs.
> +
> +	clock: clock-controller@10030000 {
> +		compatible = "samsung,exynos4412-clock";
> +		reg = <0x10030000 0x18000>;
> +		#clock-cells = <1>;
> +	};
> +
> +	isp_clock: clock-controller@10048000 {
> +		compatible = "samsung,exynos4412-isp-clock";
> +		reg = <0x10048000 0x1000>;
> +		#clock-cells = <1>;
> +		power-domains = <&pd_isp>;
> +		clocks = <&clock CLK_ACLK200>, <&clock CLK_ACLK400_MCUISP>;
> +		clock-names = "aclk200", "aclk400_mcuisp";
> +	};
> diff --git a/drivers/clk/samsung/Makefile b/drivers/clk/samsung/Makefile
> index 7afc21dc374e..8a67a3bb6803 100644
> --- a/drivers/clk/samsung/Makefile
> +++ b/drivers/clk/samsung/Makefile
> @@ -5,6 +5,7 @@
>  obj-$(CONFIG_COMMON_CLK)	+= clk.o clk-pll.o clk-cpu.o
>  obj-$(CONFIG_SOC_EXYNOS3250)	+= clk-exynos3250.o
>  obj-$(CONFIG_ARCH_EXYNOS4)	+= clk-exynos4.o
> +obj-$(CONFIG_ARCH_EXYNOS4)	+= clk-exynos4412-isp.o
>  obj-$(CONFIG_SOC_EXYNOS5250)	+= clk-exynos5250.o
>  obj-$(CONFIG_SOC_EXYNOS5260)	+= clk-exynos5260.o
>  obj-$(CONFIG_SOC_EXYNOS5410)	+= clk-exynos5410.o
> diff --git a/drivers/clk/samsung/clk-exynos4412-isp.c b/drivers/clk/samsung/clk-exynos4412-isp.c
> new file mode 100644
> index 000000000000..6712db52e047
> --- /dev/null
> +++ b/drivers/clk/samsung/clk-exynos4412-isp.c
> @@ -0,0 +1,179 @@
> +/*
> + * Copyright (c) 2017 Samsung Electronics Co., Ltd.
> + * Author: Marek Szyprowski <m.szyprowski@samsung.com>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + * Common Clock Framework support for Exynos4412 ISP module.
> +*/
> +
> +#include <dt-bindings/clock/exynos4.h>
> +#include <linux/slab.h>
> +#include <linux/clk.h>
> +#include <linux/clk-provider.h>
> +#include <linux/of.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm_runtime.h>
> +
> +#include "clk.h"
> +
> +/* Exynos4x12 specific registers, which belong to ISP power domain */
> +#define E4X12_DIV_ISP0		0x0300
> +#define E4X12_DIV_ISP1		0x0304
> +#define E4X12_GATE_ISP0		0x0800
> +#define E4X12_GATE_ISP1		0x0804
> +
> +/*
> + * Support for CMU save/restore across system suspends
> + */
> +static struct samsung_clk_reg_dump *exynos4x12_save_isp;
> +
> +static const unsigned long exynos4x12_clk_isp_save[] __initconst = {
> +	E4X12_DIV_ISP0,
> +	E4X12_DIV_ISP1,
> +	E4X12_GATE_ISP0,
> +	E4X12_GATE_ISP1,
> +};
> +
> +PNAME(mout_user_aclk400_mcuisp_p4x12) = {"fin_pll", "div_aclk400_mcuisp", };

                                            ^^ one space here, before quote

> +
> +static struct samsung_div_clock exynos4x12_isp_div_clks[] = {
> +	DIV(CLK_ISP_DIV_ISP0, "div_isp0", "aclk200", E4X12_DIV_ISP0, 0, 3),
> +	DIV(CLK_ISP_DIV_ISP1, "div_isp1", "aclk200", E4X12_DIV_ISP0, 4, 3),
> +	DIV(CLK_ISP_DIV_MCUISP0, "div_mcuisp0", "aclk400_mcuisp",
> +	    E4X12_DIV_ISP1, 4, 3),
> +	DIV(CLK_ISP_DIV_MCUISP1, "div_mcuisp1", "div_mcuisp0",
> +	    E4X12_DIV_ISP1, 8, 3),
> +	DIV(0, "div_mpwm", "div_isp1", E4X12_DIV_ISP1, 0, 3),
> +};
> +
> +static struct samsung_gate_clock exynos4x12_isp_gate_clks[] = {
> +	GATE(CLK_ISP_FIMC_ISP, "isp", "aclk200", E4X12_GATE_ISP0, 0, 0, 0),
> +	GATE(CLK_ISP_FIMC_DRC, "drc", "aclk200", E4X12_GATE_ISP0, 1, 0, 0),
> +	GATE(CLK_ISP_FIMC_FD, "fd", "aclk200", E4X12_GATE_ISP0, 2, 0, 0),
> +	GATE(CLK_ISP_FIMC_LITE0, "lite0", "aclk200", E4X12_GATE_ISP0, 3, 0, 0),
> +	GATE(CLK_ISP_FIMC_LITE1, "lite1", "aclk200", E4X12_GATE_ISP0, 4, 0, 0),
> +	GATE(CLK_ISP_MCUISP, "mcuisp", "aclk200", E4X12_GATE_ISP0, 5, 0, 0),
> +	GATE(CLK_ISP_GICISP, "gicisp", "aclk200", E4X12_GATE_ISP0, 7, 0, 0),
> +	GATE(CLK_ISP_SMMU_ISP, "smmu_isp", "aclk200", E4X12_GATE_ISP0, 8, 0, 0),
> +	GATE(CLK_ISP_SMMU_DRC, "smmu_drc", "aclk200", E4X12_GATE_ISP0, 9, 0, 0),
> +	GATE(CLK_ISP_SMMU_FD, "smmu_fd", "aclk200", E4X12_GATE_ISP0, 10, 0, 0),
> +	GATE(CLK_ISP_SMMU_LITE0, "smmu_lite0", "aclk200", E4X12_GATE_ISP0, 11,
> +	     0, 0),
> +	GATE(CLK_ISP_SMMU_LITE1, "smmu_lite1", "aclk200", E4X12_GATE_ISP0, 12,
> +	     0, 0),
> +	GATE(CLK_ISP_PPMUISPMX, "ppmuispmx", "aclk200", E4X12_GATE_ISP0, 20,
> +	     0, 0),
> +	GATE(CLK_ISP_PPMUISPX, "ppmuispx", "aclk200", E4X12_GATE_ISP0, 21,
> +	     0, 0),
> +	GATE(CLK_ISP_MCUCTL_ISP, "mcuctl_isp", "aclk200", E4X12_GATE_ISP0, 23,
> +	     0, 0),
> +	GATE(CLK_ISP_MPWM_ISP, "mpwm_isp", "aclk200", E4X12_GATE_ISP0, 24,
> +	     0, 0),
> +	GATE(CLK_ISP_I2C0_ISP, "i2c0_isp", "aclk200", E4X12_GATE_ISP0, 25,
> +	     0, 0),
> +	GATE(CLK_ISP_I2C1_ISP, "i2c1_isp", "aclk200", E4X12_GATE_ISP0, 26,
> +	     0, 0),
> +	GATE(CLK_ISP_MTCADC_ISP, "mtcadc_isp", "aclk200", E4X12_GATE_ISP0, 27,
> +	     0, 0),
> +	GATE(CLK_ISP_PWM_ISP, "pwm_isp", "aclk200", E4X12_GATE_ISP0, 28, 0, 0),
> +	GATE(CLK_ISP_WDT_ISP, "wdt_isp", "aclk200", E4X12_GATE_ISP0, 30, 0, 0),
> +	GATE(CLK_ISP_UART_ISP, "uart_isp", "aclk200", E4X12_GATE_ISP0, 31,
> +	     0, 0),
> +	GATE(CLK_ISP_ASYNCAXIM, "asyncaxim", "aclk200", E4X12_GATE_ISP1, 0,
> +	     0, 0),
> +	GATE(CLK_ISP_SMMU_ISPCX, "smmu_ispcx", "aclk200", E4X12_GATE_ISP1, 4,
> +	     0, 0),
> +	GATE(CLK_ISP_SPI0_ISP, "spi0_isp", "aclk200", E4X12_GATE_ISP1, 12,
> +	     0, 0),
> +	GATE(CLK_ISP_SPI1_ISP, "spi1_isp", "aclk200", E4X12_GATE_ISP1, 13,
> +	     0, 0),
> +};
> +
> +static int __maybe_unused exynos4x12_isp_clk_suspend(struct device *dev)
> +{
> +	struct samsung_clk_provider *ctx = dev_get_drvdata(dev);
> +
> +	samsung_clk_save(ctx->reg_base, exynos4x12_save_isp,
> +			 ARRAY_SIZE(exynos4x12_clk_isp_save));
> +	return 0;
> +}
> +
> +static int __maybe_unused exynos4x12_isp_clk_resume(struct device *dev)
> +{
> +	struct samsung_clk_provider *ctx = dev_get_drvdata(dev);
> +
> +	samsung_clk_restore(ctx->reg_base, exynos4x12_save_isp,
> +			    ARRAY_SIZE(exynos4x12_clk_isp_save));
> +	return 0;
> +}
> +
> +static int __init exynos4x12_isp_clk_probe(struct platform_device *pdev)
> +{
> +	struct samsung_clk_provider *ctx;
> +	struct device *dev = &pdev->dev;
> +	struct device_node *np = dev->of_node;
> +	struct resource *res;
> +	void __iomem *reg_base;
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	reg_base = devm_ioremap_resource(dev, res);
> +	if (IS_ERR(reg_base)) {
> +		dev_err(dev, "failed to map registers\n");
> +		return PTR_ERR(reg_base);
> +	}
> +
> +	exynos4x12_save_isp = samsung_clk_alloc_reg_dump(exynos4x12_clk_isp_save,
> +					ARRAY_SIZE(exynos4x12_clk_isp_save));
> +	if (!exynos4x12_save_isp)
> +		return -ENOMEM;
> +
> +	ctx = samsung_clk_init(np, reg_base, CLK_NR_ISP_CLKS);
> +	ctx->dev = dev;
> +
> +	platform_set_drvdata(pdev, ctx);
> +
> +	pm_runtime_set_active(dev);
> +	pm_runtime_enable(dev);
> +	pm_runtime_get_sync(dev);
> +
> +	samsung_clk_register_div(ctx, exynos4x12_isp_div_clks,
> +				 ARRAY_SIZE(exynos4x12_isp_div_clks));
> +	samsung_clk_register_gate(ctx, exynos4x12_isp_gate_clks,
> +				  ARRAY_SIZE(exynos4x12_isp_gate_clks));
> +
> +	samsung_clk_of_add_provider(np, ctx);
> +	pm_runtime_put(dev);
> +
> +	return 0;
> +}
> +
> +static const struct of_device_id exynos4x12_isp_clk_of_match[] = {
> +	{ .compatible = "samsung,exynos4412-isp-clock", },
> +	{ },
> +};
> +
> +static const struct dev_pm_ops exynos4x12_isp_pm_ops = {
> +	SET_RUNTIME_PM_OPS(exynos4x12_isp_clk_suspend,
> +			   exynos4x12_isp_clk_resume, NULL)
> +	SET_LATE_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
> +				     pm_runtime_force_resume)
> +};
> +
> +static struct platform_driver exynos4x12_isp_clk_driver __refdata = {
> +	.driver	= {
> +		.name = "exynos4x12-isp-clk",
> +		.of_match_table = exynos4x12_isp_clk_of_match,
> +		.suppress_bind_attrs = true,
> +		.pm = &exynos4x12_isp_pm_ops,
> +	},
> +	.probe = exynos4x12_isp_clk_probe,
> +};
> +
> +static int __init exynos4x12_isp_clk_init(void)
> +{
> +	return platform_driver_register(&exynos4x12_isp_clk_driver);
> +}
> +core_initcall(exynos4x12_isp_clk_init);
> diff --git a/include/dt-bindings/clock/exynos4.h b/include/dt-bindings/clock/exynos4.h
> index c40111f36d5e..bf44a7c5eccc 100644
> --- a/include/dt-bindings/clock/exynos4.h
> +++ b/include/dt-bindings/clock/exynos4.h
> @@ -272,4 +272,39 @@
>  /* must be greater than maximal clock id */
>  #define CLK_NR_CLKS		461
>  
> +/* Exynos4x12 ISP clocks */
> +#define CLK_ISP_FIMC_ISP		 1
> +#define CLK_ISP_FIMC_DRC		 2
> +#define CLK_ISP_FIMC_FD			 3
> +#define CLK_ISP_FIMC_LITE0		 4
> +#define CLK_ISP_FIMC_LITE1		 5
> +#define CLK_ISP_MCUISP			 6
> +#define CLK_ISP_GICISP			 7
> +#define CLK_ISP_SMMU_ISP		 8
> +#define CLK_ISP_SMMU_DRC		 9
> +#define CLK_ISP_SMMU_FD			10
> +#define CLK_ISP_SMMU_LITE0		11
> +#define CLK_ISP_SMMU_LITE1		12
> +#define CLK_ISP_PPMUISPMX		13
> +#define CLK_ISP_PPMUISPX		14
> +#define CLK_ISP_MCUCTL_ISP		15
> +#define CLK_ISP_MPWM_ISP		16
> +#define CLK_ISP_I2C0_ISP		17
> +#define CLK_ISP_I2C1_ISP		18
> +#define CLK_ISP_MTCADC_ISP		19
> +#define CLK_ISP_PWM_ISP			20
> +#define CLK_ISP_WDT_ISP			21
> +#define CLK_ISP_UART_ISP		22
> +#define CLK_ISP_ASYNCAXIM		23
> +#define CLK_ISP_SMMU_ISPCX		24
> +#define CLK_ISP_SPI0_ISP		25
> +#define CLK_ISP_SPI1_ISP		26
> +

Do you expect here more clocks?

Best regards,
Krzysztof


> +#define CLK_ISP_DIV_ISP0		30
> +#define CLK_ISP_DIV_ISP1		31
> +#define CLK_ISP_DIV_MCUISP0		32
> +#define CLK_ISP_DIV_MCUISP1		33
> +
> +#define CLK_NR_ISP_CLKS			34
> +
>  #endif /* _DT_BINDINGS_CLOCK_EXYNOS_4_H */
> -- 
> 2.14.2
>