[U-Boot] [PATCH 12/26] clk: add clock gating driver for MediaTek MIPS platform

[Weijie Gao]

On Wed, 2019-08-28 at 15:24 +0200, Daniel Schwierzeck wrote:
> 
> Am 28.08.19 um 08:37 schrieb Weijie Gao:
> > This patch adds clock gating driver for MediaTek MIPS platform
> > 
> > Signed-off-by: Weijie Gao <weijie.gao at mediatek.com>
> > ---
> >  drivers/clk/Kconfig                  |  8 ++++
> >  drivers/clk/Makefile                 |  1 +
> >  drivers/clk/clk-mtmips-cg.c          | 63 ++++++++++++++++++++++++++++
> >  include/dt-bindings/clk/mt7628-clk.h | 31 ++++++++++++++
> >  4 files changed, 103 insertions(+)
> >  create mode 100644 drivers/clk/clk-mtmips-cg.c
> >  create mode 100644 include/dt-bindings/clk/mt7628-clk.h
> > 
> > diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig
> > index 95fe0aea2c..0762a42476 100644
> > --- a/drivers/clk/Kconfig
> > +++ b/drivers/clk/Kconfig
> > @@ -160,4 +160,12 @@ config SANDBOX_CLK_CCF
> >  	  Enable this option if you want to test the Linux kernel's Common
> >  	  Clock Framework [CCF] code in U-Boot's Sandbox clock driver.
> >  
> > +config CLK_MTMIPS_GATE
> > +	bool "Enable clock gating driver for MediaTek MIPS platform"
> > +	depends on CLK && ARCH_MTMIPS
> > +	default y
> > +	help
> > +	  Enable clock gating driver for MediaTek MIPS platform.
> > +	  This driver supports only clock enable and disable.
> > +
> >  endmenu
> > diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
> > index 68aabe1ca9..353974d784 100644
> > --- a/drivers/clk/Makefile
> > +++ b/drivers/clk/Makefile
> > @@ -26,6 +26,7 @@ obj-$(CONFIG_CLK_BOSTON) += clk_boston.o
> >  obj-$(CONFIG_CLK_EXYNOS) += exynos/
> >  obj-$(CONFIG_CLK_HSDK) += clk-hsdk-cgu.o
> >  obj-$(CONFIG_CLK_MPC83XX) += mpc83xx_clk.o
> > +obj-$(CONFIG_CLK_MTMIPS_GATE) += clk-mtmips-cg.o
> >  obj-$(CONFIG_CLK_OWL) += owl/
> >  obj-$(CONFIG_CLK_RENESAS) += renesas/
> >  obj-$(CONFIG_CLK_SIFIVE) += sifive/
> > diff --git a/drivers/clk/clk-mtmips-cg.c b/drivers/clk/clk-mtmips-cg.c
> > new file mode 100644
> > index 0000000000..0221d95aed
> > --- /dev/null
> > +++ b/drivers/clk/clk-mtmips-cg.c
> > @@ -0,0 +1,63 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * Copyright (C) 2019 MediaTek Inc. All Rights Reserved.
> > + *
> > + * Author: Weijie Gao <weijie.gao at mediatek.com>
> > + */
> > +
> > +#include <common.h>
> > +#include <clk-uclass.h>
> > +#include <dm.h>
> > +#include <asm/io.h>
> > +
> > +struct mtmips_clk_gate_priv {
> > +	void __iomem *base;
> > +};
> > +
> > +static int mtmips_clk_gate_enable(struct clk *clk)
> > +{
> > +	struct mtmips_clk_gate_priv *priv = dev_get_priv(clk->dev);
> > +
> > +	setbits_32(priv->base, BIT(clk->id));
> > +
> > +	return 0;
> > +}
> > +
> > +static int mtmips_clk_gate_disable(struct clk *clk)
> > +{
> > +	struct mtmips_clk_gate_priv *priv = dev_get_priv(clk->dev);
> > +
> > +	clrbits_32(priv->base, BIT(clk->id));
> > +
> > +	return 0;
> > +}
> > +
> > +const struct clk_ops mtmips_clk_gate_ops = {
> > +	.enable = mtmips_clk_gate_enable,
> > +	.disable = mtmips_clk_gate_disable,
> > +};
> 
> the generic clk-gate.c driver already supports this simple register bit
> toggling. Why don't you use that one?
> 
> > +
> > +static int mtmips_clk_gate_probe(struct udevice *dev)
> > +{
> > +	struct mtmips_clk_gate_priv *priv = dev_get_priv(dev);
> > +
> > +	priv->base = (void __iomem *)dev_remap_addr_index(dev, 0);
> > +	if (!priv->base)
> > +		return -EINVAL;
> > +
> > +	return 0;
> > +}
> > +
> > +static const struct udevice_id mtmips_clk_gate_ids[] = {
> > +	{ .compatible = "mediatek,mtmips-clk-gate" },
> > +	{ }
> > +};
> > +
> > +U_BOOT_DRIVER(mtmips_clk_gate) = {
> > +	.name = "mtmips-clk-gate",
> > +	.id = UCLASS_CLK,
> > +	.of_match = mtmips_clk_gate_ids,
> > +	.probe = mtmips_clk_gate_probe,
> > +	.priv_auto_alloc_size = sizeof(struct mtmips_clk_gate_priv),
> > +	.ops = &mtmips_clk_gate_ops,
> > +};
> > diff --git a/include/dt-bindings/clk/mt7628-clk.h b/include/dt-bindings/clk/mt7628-clk.h
> > new file mode 100644
> > index 0000000000..6784d6e50b
> > --- /dev/null
> > +++ b/include/dt-bindings/clk/mt7628-clk.h
> > @@ -0,0 +1,31 @@
> > +/* SPDX-License-Identifier: GPL-2.0 */
> > +/*
> > + * Copyright (C) 2019 MediaTek Inc.
> > + *
> > + * Author:  Weijie Gao <weijie.gao at mediatek.com>
> > + */
> > +
> > +#ifndef _DT_BINDINGS_MT7628_CLK_H_
> > +#define _DT_BINDINGS_MT7628_CLK_H_
> > +
> > +#define MT7628_PWM_CLK			31
> > +#define MT7628_SDXC_CLK			30
> > +#define MT7628_CRYPTO_CLK		29
> > +#define MT7628_MIPS_CNT_CLK		28
> > +#define MT7628_PCIE_CLK			26
> > +#define MT7628_UPHY_CLK			25
> > +#define MT7628_ETH_CLK			23
> > +#define MT7628_UART2_CLK		20
> > +#define MT7628_UART1_CLK		19
> > +#define MT7628_SPI_CLK			18
> > +#define MT7628_I2S_CLK			17
> > +#define MT7628_I2C_CLK			16
> > +#define MT7628_GDMA_CLK			14
> > +#define MT7628_PIO_CLK			13
> > +#define MT7628_UART0_CLK		12
> > +#define MT7628_PCM_CLK			11
> > +#define MT7628_MC_CLK			10
> > +#define MT7628_INT_CLK			9
> > +#define MT7628_TIMER_CLK		8
> > +
> > +#endif /* _DT_BINDINGS_MT7628_CLK_H_ */
> > 
> 


I've written this driver in the early July, before clk-gate was added.
I didn't notice this driver yesterday.
I will try to switch to clk-gate.