Re: [linux-sunxi] [PATCH resend 2/6] clk: sunxi: Add VE (Video Engine) module clock driver for sun[457]i

[Jens Kuske <jenskuske@gmail.com>]

On 05/12/15 14:16, Chen-Yu Tsai wrote:
> The video engine has its own special module clock, consisting of a clock
> gate, configurable dividers, and a reset control.
> 

Hi,

I've tested these patches on A20, everything works so far.
I only read some bits from a random bitstream, so nothing fancy yet, but
it shows that both dram and module clock are working.

One small indentation error below, otherwise it looks good.

> On later (sun[68]i) families, the reset control is moved out of this
> piece of hardware and grouped with reset controls of other peripherals.
> 
> Signed-off-by: Chen-Yu Tsai <wens@csie.org>
> ---
>  Documentation/devicetree/bindings/clock/sunxi.txt |   4 +
>  drivers/clk/sunxi/Makefile                        |   1 +
>  drivers/clk/sunxi/clk-a10-ve.c                    | 171 ++++++++++++++++++++++
>  3 files changed, 176 insertions(+)
>  create mode 100644 drivers/clk/sunxi/clk-a10-ve.c
> 
> diff --git a/Documentation/devicetree/bindings/clock/sunxi.txt b/Documentation/devicetree/bindings/clock/sunxi.txt
> index ef0b452806b1..14496056319f 100644
> --- a/Documentation/devicetree/bindings/clock/sunxi.txt
> +++ b/Documentation/devicetree/bindings/clock/sunxi.txt
> @@ -74,6 +74,7 @@ Required properties:
>  	"allwinner,sun8i-h3-usb-clk" - for usb gates + resets on H3
>  	"allwinner,sun9i-a80-usb-mod-clk" - for usb gates + resets on A80
>  	"allwinner,sun9i-a80-usb-phy-clk" - for usb phy gates + resets on A80
> +	"allwinner,sun4i-a10-ve-clk" - for the Video Engine clock
>  
>  Required properties for all clocks:
>  - reg : shall be the control register address for the clock.
> @@ -93,6 +94,9 @@ Required properties for all clocks:
>  And "allwinner,*-usb-clk" clocks also require:
>  - reset-cells : shall be set to 1
>  
> +The "allwinner,sun4i-a10-ve-clk" clock also requires:
> +- reset-cells : shall be set to 0
> +
>  The "allwinner,sun9i-a80-mmc-config-clk" clock also requires:
>  - #reset-cells : shall be set to 1
>  - resets : shall be the reset control phandle for the mmc block.
> diff --git a/drivers/clk/sunxi/Makefile b/drivers/clk/sunxi/Makefile
> index 103efab05ca8..78db91ad5af6 100644
> --- a/drivers/clk/sunxi/Makefile
> +++ b/drivers/clk/sunxi/Makefile
> @@ -7,6 +7,7 @@ obj-y += clk-a10-codec.o
>  obj-y += clk-a10-hosc.o
>  obj-y += clk-a10-mod1.o
>  obj-y += clk-a10-pll2.o
> +obj-y += clk-a10-ve.o
>  obj-y += clk-a20-gmac.o
>  obj-y += clk-mod0.o
>  obj-y += clk-simple-gates.o
> diff --git a/drivers/clk/sunxi/clk-a10-ve.c b/drivers/clk/sunxi/clk-a10-ve.c
> new file mode 100644
> index 000000000000..de0fdb656150
> --- /dev/null
> +++ b/drivers/clk/sunxi/clk-a10-ve.c
> @@ -0,0 +1,171 @@
> +/*
> + * Copyright 2015 Chen-Yu Tsai
> + *
> + * Chen-Yu Tsai <wens@csie.org>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * 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/clk-provider.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/reset-controller.h>
> +#include <linux/slab.h>
> +#include <linux/spinlock.h>
> +
> +static DEFINE_SPINLOCK(ve_lock);
> +
> +#define SUN4I_VE_ENABLE		31
> +#define SUN4I_VE_DIVIDER_SHIFT	16
> +#define SUN4I_VE_DIVIDER_WIDTH	3
> +#define SUN4I_VE_RESET		0
> +
> +/**
> + * sunxi_ve_reset... - reset bit in ve clk registers handling
> + */
> +
> +struct ve_reset_data {
> +	void __iomem			*reg;
> +	spinlock_t			*lock;
> +	struct reset_controller_dev	rcdev;
> +};
> +
> +static int sunxi_ve_reset_assert(struct reset_controller_dev *rcdev,
> +				 unsigned long id)
> +{
> +	struct ve_reset_data *data = container_of(rcdev,
> +						  struct ve_reset_data,
> +						  rcdev);
> +	unsigned long flags;
> +	u32 reg;
> +
> +	spin_lock_irqsave(data->lock, flags);
> +
> +	reg = readl(data->reg);
> +	writel(reg & ~BIT(SUN4I_VE_RESET), data->reg);
> +
> +	spin_unlock_irqrestore(data->lock, flags);
> +
> +	return 0;
> +}
> +
> +static int sunxi_ve_reset_deassert(struct reset_controller_dev *rcdev,
> +				   unsigned long id)
> +{
> +	struct ve_reset_data *data = container_of(rcdev,
> +						  struct ve_reset_data,
> +						  rcdev);
> +	unsigned long flags;
> +	u32 reg;
> +
> +	spin_lock_irqsave(data->lock, flags);
> +
> +	reg = readl(data->reg);
> +	writel(reg | BIT(SUN4I_VE_RESET), data->reg);
> +
> +	spin_unlock_irqrestore(data->lock, flags);
> +
> +	return 0;
> +}
> +
> +static int sunxi_ve_of_xlate(struct reset_controller_dev *rcdev,
> +			     const struct of_phandle_args *reset_spec)
> +{
> +    if (WARN_ON(reset_spec->args_count != 0))
> +	return -EINVAL;
> +
> +    return 0;
    ^
Spaces instead of tabs here.

> +}
> +
> +static struct reset_control_ops sunxi_ve_reset_ops = {
> +	.assert		= sunxi_ve_reset_assert,
> +	.deassert	= sunxi_ve_reset_deassert,
> +};
> +
> +static void __init sun4i_ve_clk_setup(struct device_node *node)
> +{
> +	struct clk *clk;
> +	struct clk_divider *div;
> +	struct clk_gate *gate;
> +	struct ve_reset_data *reset_data;
> +	const char *parent;
> +	const char *clk_name = node->name;
> +	void __iomem *reg;
> +	int err;
> +
> +	reg = of_io_request_and_map(node, 0, of_node_full_name(node));
> +	if (IS_ERR(reg))
> +		return;
> +
> +	div = kzalloc(sizeof(*div), GFP_KERNEL);
> +	if (!div)
> +		goto err_unmap;
> +
> +	gate = kzalloc(sizeof(*gate), GFP_KERNEL);
> +	if (!gate)
> +		goto err_free_div;
> +
> +	of_property_read_string(node, "clock-output-names", &clk_name);
> +	parent = of_clk_get_parent_name(node, 0);
> +
> +	gate->reg = reg;
> +	gate->bit_idx = SUN4I_VE_ENABLE;
> +	gate->lock = &ve_lock;
> +
> +	div->reg = reg;
> +	div->shift = SUN4I_VE_DIVIDER_SHIFT;
> +	div->width = SUN4I_VE_DIVIDER_WIDTH;
> +	div->lock = &ve_lock;
> +
> +	clk = clk_register_composite(NULL, clk_name, &parent, 1,
> +				     NULL, NULL,
> +				     &div->hw, &clk_divider_ops,
> +				     &gate->hw, &clk_gate_ops,
> +				     CLK_SET_RATE_PARENT);
> +	if (IS_ERR(clk))
> +		goto err_free_gate;
> +
> +	err = of_clk_add_provider(node, of_clk_src_simple_get, clk);
> +	if (err)
> +		goto err_unregister_clk;
> +
> +	reset_data = kzalloc(sizeof(*reset_data), GFP_KERNEL);
> +	if (!reset_data)
> +		goto err_del_provider;
> +
> +	reset_data->reg = reg;
> +	reset_data->lock = &ve_lock;
> +	reset_data->rcdev.nr_resets = 1;
> +	reset_data->rcdev.ops = &sunxi_ve_reset_ops;
> +	reset_data->rcdev.of_node = node;
> +	reset_data->rcdev.of_xlate = sunxi_ve_of_xlate;
> +	reset_data->rcdev.of_reset_n_cells = 0;
> +	err = reset_controller_register(&reset_data->rcdev);
> +	if (err)
> +		goto err_free_reset;
> +
> +	return;
> +
> +err_free_reset:
> +	kfree(reset_data);
> +err_del_provider:
> +	of_clk_del_provider(node);
> +err_unregister_clk:
> +	clk_unregister(clk);
> +err_free_gate:
> +	kfree(gate);
> +err_free_div:
> +	kfree(div);
> +err_unmap:
> +	iounmap(reg);
> +}
> +CLK_OF_DECLARE(sun4i_ve, "allwinner,sun4i-a10-ve-clk",
> +	       sun4i_ve_clk_setup);
>