[PATCH] timer: starfive: Add Starfive timer support

[WeiLiang Lim]

Can anyone help review this patch please?

> -----Original Message-----
> From: KuanLim.Lee <kuanlim.lee at starfivetech.com>
> Sent: Tuesday, September 19, 2023 3:31 PM
> To: u-boot at lists.denx.de
> Cc: WeiLiang Lim <weiliang.lim at starfivetech.com>; KuanLim.Lee
> <kuanlim.lee at starfivetech.com>
> Subject: [PATCH] timer: starfive: Add Starfive timer support
> 
> Add timer driver in Starfive SoC. It is an timer that outside of CPU core and
> inside Starfive SoC.
> 
> Signed-off-by: Kuan Lim Lee <kuanlim.lee at starfivetech.com>
> Reviewed-by: Wei Liang Lim <weiliang.lim at starfivetech.com>
> ---
>  drivers/timer/Kconfig          |  7 +++
>  drivers/timer/Makefile         |  1 +
>  drivers/timer/starfive-timer.c | 94
> ++++++++++++++++++++++++++++++++++
>  3 files changed, 102 insertions(+)
>  create mode 100644 drivers/timer/starfive-timer.c
> 
> diff --git a/drivers/timer/Kconfig b/drivers/timer/Kconfig index
> 915b2af160..a98be9dfae 100644
> --- a/drivers/timer/Kconfig
> +++ b/drivers/timer/Kconfig
> @@ -326,4 +326,11 @@ config XILINX_TIMER
>  	  Select this to enable support for the timer found on
>  	  any Xilinx boards (axi timer).
> 
> +config STARFIVE_TIMER
> +	bool "Starfive timer support"
> +	depends on TIMER
> +	help
> +	  Select this to enable support for the timer found on
> +	  Starfive SoC.
> +
>  endmenu
> diff --git a/drivers/timer/Makefile b/drivers/timer/Makefile index
> 1ca74805fd..1ef814970b 100644
> --- a/drivers/timer/Makefile
> +++ b/drivers/timer/Makefile
> @@ -34,3 +34,4 @@ obj-$(CONFIG_MTK_TIMER)		+=
> mtk_timer.o
>  obj-$(CONFIG_MCHP_PIT64B_TIMER)	+= mchp-pit64b-timer.o
>  obj-$(CONFIG_IMX_GPT_TIMER)	+= imx-gpt-timer.o
>  obj-$(CONFIG_XILINX_TIMER)	+= xilinx-timer.o
> +obj-$(CONFIG_STARFIVE_TIMER)	+= starfive-timer.o
> diff --git a/drivers/timer/starfive-timer.c b/drivers/timer/starfive-timer.c new
> file mode 100644 index 0000000000..816402fdbf
> --- /dev/null
> +++ b/drivers/timer/starfive-timer.c
> @@ -0,0 +1,94 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Copyright 2022 StarFive, Inc. All rights reserved.
> + *   Author: Lee Kuan Lim <kuanlim.lee at starfivetech.com>
> + */
> +
> +#include <common.h>
> +#include <clk.h>
> +#include <dm.h>
> +#include <time.h>
> +#include <timer.h>
> +#include <asm/io.h>
> +#include <dm/device-internal.h>
> +#include <linux/err.h>
> +
> +#define	STF_TIMER_INT_STATUS	0x00
> +#define STF_TIMER_CTL		0x04
> +#define STF_TIMER_LOAD		0x08
> +#define STF_TIMER_ENABLE	0x10
> +#define STF_TIMER_RELOAD	0x14
> +#define STF_TIMER_VALUE		0x18
> +#define STF_TIMER_INT_CLR	0x20
> +#define STF_TIMER_INT_MASK	0x24
> +
> +struct starfive_timer_priv {
> +	void __iomem *base;
> +	u32 timer_size;
> +};
> +
> +static u64 notrace starfive_get_count(struct udevice *dev) {
> +	struct starfive_timer_priv *priv = dev_get_priv(dev);
> +
> +	/* Read decrement timer value and convert to increment value */
> +	return priv->timer_size - readl(priv->base + STF_TIMER_VALUE); }
> +
> +static const struct timer_ops starfive_ops = {
> +	.get_count = starfive_get_count,
> +};
> +
> +static int starfive_probe(struct udevice *dev) {
> +	struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev);
> +	struct starfive_timer_priv *priv = dev_get_priv(dev);
> +	int timer_channel;
> +	struct clk clk;
> +	int ret;
> +
> +	priv->base = dev_read_addr_ptr(dev);
> +	if (IS_ERR(priv->base))
> +		return PTR_ERR(priv->base);
> +
> +	timer_channel = dev_read_u32_default(dev, "channel", 0);
> +	priv->base = priv->base + (0x40 * timer_channel);
> +
> +	/* Get clock rate from channel selectecd*/
> +	ret = clk_get_by_index(dev, timer_channel, &clk);
> +	if (ret)
> +		return ret;
> +
> +	ret = clk_enable(&clk);
> +	if (ret)
> +		return ret;
> +	uc_priv->clock_rate = clk_get_rate(&clk);
> +
> +	/* Initiate timer, channel 0 */
> +	/* Unmask Interrupt Mask */
> +	writel(0, priv->base + STF_TIMER_INT_MASK);
> +	/* Single run mode Setting */
> +	if (dev_read_bool(dev, "single-run"))
> +		writel(1, priv->base + STF_TIMER_CTL);
> +	/* Set Reload value */
> +	priv->timer_size = dev_read_u32_default(dev, "timer-size", 0xffffffff);
> +	writel(priv->timer_size, priv->base + STF_TIMER_LOAD);
> +	/* Enable to start timer */
> +	writel(1, priv->base + STF_TIMER_ENABLE);
> +
> +	return 0;
> +}
> +
> +static const struct udevice_id starfive_ids[] = {
> +	{ .compatible = "starfive,jh8100-timers" },
> +	{ }
> +};
> +
> +U_BOOT_DRIVER(jh8100_starfive_timer) = {
> +	.name		= "jh8100_starfive_timer",
> +	.id		= UCLASS_TIMER,
> +	.of_match	= starfive_ids,
> +	.probe		= starfive_probe,
> +	.ops		= &starfive_ops,
> +	.priv_auto	= sizeof(struct starfive_timer_priv),
> +};
> --
> 2.34.1