Re: [PATCH 3/3] cpufreq: Switch imx7d to imx-cpufreq-dt for speed grading

From: Viresh Kumar <viresh.kumar@linaro.org>
To: Leonard Crestez <leonard.crestez@nxp.com>
Cc: Shawn Guo <shawnguo@kernel.org>, Jacky Bai <ping.bai@nxp.com>,
	"Rafael J. Wysocki" <rjw@rjwysocki.net>,
	Anson Huang <anson.huang@nxp.com>, Abel Vesa <abel.vesa@nxp.com>,
	Aisheng Dong <aisheng.dong@nxp.com>,
	Fabio Estevam <fabio.estevam@nxp.com>,
	"linux-pm@vger.kernel.org" <linux-pm@vger.kernel.org>,
	"kernel@pengutronix.de" <kernel@pengutronix.de>,
	dl-linux-imx <linux-imx@nxp.com>,
	"linux-arm-kernel@lists.infradead.org" 
	<linux-arm-kernel@lists.infradead.org>
Subject: Re: [PATCH 3/3] cpufreq: Switch imx7d to imx-cpufreq-dt for speed grading
Date: Mon, 3 Jun 2019 11:08:50 +0530	[thread overview]
Message-ID: <20190603053850.tkskdzcloir4k3kw@vireshk-i7> (raw)
In-Reply-To: <8787934ff35e7e55837f2caabc0d5bf65828d971.1559131365.git.leonard.crestez@nxp.com>

On 29-05-19, 12:03, Leonard Crestez wrote:
> This driver can handle speed grading bits on imx7d just like on imx8mq
> and imx8mm.
> 
> Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
> ---
>  arch/arm/mach-imx/mach-imx7d.c       | 7 +++++++
>  drivers/cpufreq/cpufreq-dt-platdev.c | 2 +-
>  drivers/cpufreq/imx-cpufreq-dt.c     | 1 +
>  3 files changed, 9 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/arm/mach-imx/mach-imx7d.c b/arch/arm/mach-imx/mach-imx7d.c
> index 26ca744d3e2b..0b77412795c9 100644
> --- a/arch/arm/mach-imx/mach-imx7d.c
> +++ b/arch/arm/mach-imx/mach-imx7d.c
> @@ -95,10 +95,16 @@ static void __init imx7d_init_machine(void)
>  
>  	imx_anatop_init();
>  	imx7d_enet_init();
>  }
>  
> +static void __init imx7d_init_late(void)
> +{
> +	if (IS_ENABLED(CONFIG_ARM_IMX_CPUFREQ_DT))
> +		platform_device_register_simple("imx-cpufreq-dt", -1, NULL, 0);
> +}
> +
>  static void __init imx7d_init_irq(void)
>  {
>  	imx_init_revision_from_anatop();
>  	imx_src_init();
>  	irqchip_init();
> @@ -111,7 +117,8 @@ static const char *const imx7d_dt_compat[] __initconst = {
>  };
>  
>  DT_MACHINE_START(IMX7D, "Freescale i.MX7 Dual (Device Tree)")
>  	.init_irq	= imx7d_init_irq,
>  	.init_machine	= imx7d_init_machine,
> +	.init_late      = imx7d_init_late,
>  	.dt_compat	= imx7d_dt_compat,
>  MACHINE_END
> diff --git a/drivers/cpufreq/cpufreq-dt-platdev.c b/drivers/cpufreq/cpufreq-dt-platdev.c
> index 19c1aad57e26..eb282dff9f2c 100644
> --- a/drivers/cpufreq/cpufreq-dt-platdev.c
> +++ b/drivers/cpufreq/cpufreq-dt-platdev.c
> @@ -38,11 +38,10 @@ static const struct of_device_id whitelist[] __initconst = {
>  	{ .compatible = "hisilicon,hi3660", },
>  
>  	{ .compatible = "fsl,imx27", },
>  	{ .compatible = "fsl,imx51", },
>  	{ .compatible = "fsl,imx53", },
> -	{ .compatible = "fsl,imx7d", },
>  
>  	{ .compatible = "marvell,berlin", },
>  	{ .compatible = "marvell,pxa250", },
>  	{ .compatible = "marvell,pxa270", },
>  
> @@ -106,10 +105,11 @@ static const struct of_device_id whitelist[] __initconst = {
>   */
>  static const struct of_device_id blacklist[] __initconst = {
>  	{ .compatible = "calxeda,highbank", },
>  	{ .compatible = "calxeda,ecx-2000", },
>  
> +	{ .compatible = "fsl,imx7d", },
>  	{ .compatible = "fsl,imx8mq", },
>  	{ .compatible = "fsl,imx8mm", },
>  
>  	{ .compatible = "marvell,armadaxp", },
>  
> diff --git a/drivers/cpufreq/imx-cpufreq-dt.c b/drivers/cpufreq/imx-cpufreq-dt.c
> index 5061503cb0a1..ce26ffc18ce6 100644
> --- a/drivers/cpufreq/imx-cpufreq-dt.c
> +++ b/drivers/cpufreq/imx-cpufreq-dt.c
> @@ -18,10 +18,11 @@
>  #define OCOTP_CFG3_SPEED_GRADE_MASK	(0x3 << 8)
>  #define OCOTP_CFG3_MKT_SEGMENT_SHIFT    6
>  #define OCOTP_CFG3_MKT_SEGMENT_MASK     (0x3 << 6)
>  
>  static const struct of_device_id imx_cpufreq_dt_match_list[] = {
> +	{ .compatible = "fsl,imx7d" },
>  	{ .compatible = "fsl,imx8mm" },
>  	{ .compatible = "fsl,imx8mq" },
>  	{}
>  };

What is the purpose of this array and can we get rid of it instead ? I am asking
as this driver gets probed only if the platform code has created the
imx-cpufreq-dt device and it shouldn't get created for other machines than what
is supported.

-- 
viresh