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[1/2] ARM: Rockchip: Handle rk3288/rk3288w revision

Message ID 20200302155703.278421-2-mylene.josserand@collabora.com (mailing list archive)
State New, archived
Headers show
Series ARM: Add Rockchip rk3288w support | expand

Commit Message

Mylene Josserand March 2, 2020, 3:57 p.m. UTC
Determine which revision of rk3288 by checking the HDMI version.
According to the Rockchip BSP kernel, on rk3288w, the HDMI
revision equals 0x1A which is not the case for the rk3288 [1].

As these SOC have some differences, the new function
'soc_is_rk3288w' will help us to know on which revision
we are.

[1]:https://github.com/rockchip-linux/u-boot/blob/f992fe3334aa5090acb448261982628b5a3d37a5/arch/arm/include/asm/arch-rockchip/cpu.h#L30..L34

Signed-off-by: Mylène Josserand <mylene.josserand@collabora.com>
---
 arch/arm/mach-rockchip/rockchip.c | 45 +++++++++++++++++++++++++++++++
 include/soc/rockchip/revision.h   | 22 +++++++++++++++
 2 files changed, 67 insertions(+)
 create mode 100644 include/soc/rockchip/revision.h

Comments

Heiko Stuebner March 4, 2020, 10:59 a.m. UTC | #1
Hi,

Am Montag, 2. März 2020, 16:57:02 CET schrieb Mylène Josserand:
> Determine which revision of rk3288 by checking the HDMI version.
> According to the Rockchip BSP kernel, on rk3288w, the HDMI
> revision equals 0x1A which is not the case for the rk3288 [1].
> 
> As these SOC have some differences, the new function
> 'soc_is_rk3288w' will help us to know on which revision
> we are.

what happened to just having a different compatible in the dts?
Aka doing a 

rk3288w.dtsi with

#include "rk3288.dtsi"

&cru {
	compatible = "rockchip,rk3288w-cru";
}

I somehow don't expect boards to just switch between soc variants
on the fly.

Also, doing things in mach-rockchip is not very future-proof:

(1) having random soc-specific APIs spanning the kernel feels wrong,
    especially as at some point it might not be contained to our own special
    drivers like the cru. I cannot really see people being enthusiastic if
    something like this would be needed in say the core Analogix-DP bridge ;-)
(2) I guess the rk3288w will not be the last soc doing this and on arm64 you
    can't do it that way, as there is no mach-rockchip there

So my personal preference would really would be just a specific compatible
for affected ip blocks.

Heiko

> [1]:https://github.com/rockchip-linux/u-boot/blob/f992fe3334aa5090acb448261982628b5a3d37a5/arch/arm/include/asm/arch-rockchip/cpu.h#L30..L34
> 
> Signed-off-by: Mylène Josserand <mylene.josserand@collabora.com>
> ---
>  arch/arm/mach-rockchip/rockchip.c | 45 +++++++++++++++++++++++++++++++
>  include/soc/rockchip/revision.h   | 22 +++++++++++++++
>  2 files changed, 67 insertions(+)
>  create mode 100644 include/soc/rockchip/revision.h
> 
> diff --git a/arch/arm/mach-rockchip/rockchip.c b/arch/arm/mach-rockchip/rockchip.c
> index f9797a2b5d0d..b907ba390093 100644
> --- a/arch/arm/mach-rockchip/rockchip.c
> +++ b/arch/arm/mach-rockchip/rockchip.c
> @@ -9,12 +9,14 @@
>  #include <linux/kernel.h>
>  #include <linux/init.h>
>  #include <linux/io.h>
> +#include <linux/of_address.h>
>  #include <linux/of_platform.h>
>  #include <linux/irqchip.h>
>  #include <linux/clk-provider.h>
>  #include <linux/clocksource.h>
>  #include <linux/mfd/syscon.h>
>  #include <linux/regmap.h>
> +#include <soc/rockchip/revision.h>
>  #include <asm/mach/arch.h>
>  #include <asm/mach/map.h>
>  #include <asm/hardware/cache-l2x0.h>
> @@ -22,6 +24,49 @@
>  #include "pm.h"
>  
>  #define RK3288_TIMER6_7_PHYS 0xff810000
> +#define RK3288_HDMI_REV_REG	0x04
> +#define RK3288W_HDMI_REV	0x1A
> +
> +static const struct of_device_id rk3288_dt_hdmi_match[] __initconst = {
> +	{ .compatible = "rockchip,rk3288-dw-hdmi" },
> +	{ }
> +};
> +
> +int rk3288_get_revision(void)
> +{
> +	static int revision = RK3288_SOC_REV_UNKNOWN;
> +	struct device_node *dn;
> +	void __iomem *hdmi_base;
> +
> +	if (revision != RK3288_SOC_REV_UNKNOWN)
> +		return revision;
> +
> +	dn = of_find_matching_node(NULL, rk3288_dt_hdmi_match);
> +	if (!dn) {
> +		pr_err("%s: Couldn't find HDMI node\n", __func__);
> +		return -EINVAL;
> +	}
> +
> +	hdmi_base = of_iomap(dn, 0);
> +	of_node_put(dn);
> +
> +	if (!hdmi_base) {
> +		pr_err("%s: Couldn't map %pOF regs\n", __func__,
> +		       hdmi_base);
> +		return -ENXIO;
> +	}
> +
> +	if (readl_relaxed(hdmi_base + RK3288_HDMI_REV_REG) ==
> +	    RK3288W_HDMI_REV)
> +		revision = RK3288_SOC_REV_RK3288W;
> +	else
> +		revision = RK3288_SOC_REV_RK3288;
> +
> +	iounmap(hdmi_base);
> +
> +	return revision;
> +}
> +EXPORT_SYMBOL(rk3288_get_revision);
>  
>  static void __init rockchip_timer_init(void)
>  {
> diff --git a/include/soc/rockchip/revision.h b/include/soc/rockchip/revision.h
> new file mode 100644
> index 000000000000..226419c60af0
> --- /dev/null
> +++ b/include/soc/rockchip/revision.h
> @@ -0,0 +1,22 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +/*
> + * Copyright 2020 Collabora
> + */
> +
> +#ifndef __SOC_ROCKCHIP_REVISION_H__
> +#define __SOC_ROCKCHIP_REVISION_H__
> +
> +enum rk3288_soc_revision {
> +	RK3288_SOC_REV_UNKNOWN,
> +	RK3288_SOC_REV_RK3288,
> +	RK3288_SOC_REV_RK3288W,
> +};
> +
> +int rk3288_get_revision(void);
> +
> +static inline bool soc_is_rk3288w(void)
> +{
> +	return rk3288_get_revision() == RK3288_SOC_REV_RK3288W;
> +}
> +
> +#endif /* __SOC_ROCKCHIP_REVISION_H__ */
>
Ezequiel Garcia March 5, 2020, 12:03 a.m. UTC | #2
Hi Heiko,

On Wed, 2020-03-04 at 11:59 +0100, Heiko Stübner wrote:
> Hi,
> 
> Am Montag, 2. März 2020, 16:57:02 CET schrieb Mylène Josserand:
> > Determine which revision of rk3288 by checking the HDMI version.
> > According to the Rockchip BSP kernel, on rk3288w, the HDMI
> > revision equals 0x1A which is not the case for the rk3288 [1].
> > 
> > As these SOC have some differences, the new function
> > 'soc_is_rk3288w' will help us to know on which revision
> > we are.
> 
> what happened to just having a different compatible in the dts?
> Aka doing a 
> 
> rk3288w.dtsi with
> 
> #include "rk3288.dtsi"
> 
> &cru {
> 	compatible = "rockchip,rk3288w-cru";
> }
> 

I guess you have something like this in mind:

static void __init rk3288_clk_init(struct device_node *np)
{
        __rk3288_clk_init(np, RK3288_SOC_REV_RK3288W);
}
CLK_OF_DECLARE(rk3288_cru, "rockchip,rk3288-cru", rk3288_clk_init);

static void __init rk3288w_clk_init(struct device_node *np)
{
        __rk3288_clk_init(np, RK3288_SOC_REV_RK3288);
}
CLK_OF_DECLARE(rk3288_cru, "rockchip,rk3288w-cru", rk3288w_clk_init);

And the rest is mostly untouched, except the revision is
no longer queried and is now passed by the DT?

This would be cleaner for the kernel, with the obvious
drawback being that you now have to maintain
another DTS.

This could be an inconvenience. I believe
RK3288W is meant as a direct replacement for RK3288,
so folks building products would expect to just use
RK3288W, and not really bother with passing a
different DTS or what not.

> I somehow don't expect boards to just switch between soc variants
> on the fly.
> 

While I agree they are nasty, quirks like this
are not uncommon.

> Also, doing things in mach-rockchip is not very future-proof:
> 

There is actually no reason to keep this in mach-rockchip, right?

The quirk could be placed in other places. For instance,
directly in the clock driver.

Thanks for reviewing!
Ezequiel

> (1) having random soc-specific APIs spanning the kernel feels wrong,
>     especially as at some point it might not be contained to our own special
>     drivers like the cru. I cannot really see people being enthusiastic if
>     something like this would be needed in say the core Analogix-DP bridge ;-)
> (2) I guess the rk3288w will not be the last soc doing this and on arm64 you
>     can't do it that way, as there is no mach-rockchip there
> 
> So my personal preference would really would be just a specific compatible
> for affected ip blocks.
> 
> Heiko
> 
> > [1]:https://github.com/rockchip-linux/u-boot/blob/f992fe3334aa5090acb448261982628b5a3d37a5/arch/arm/include/asm/arch-rockchip/cpu.h#L30..L34
> > 
> > Signed-off-by: Mylène Josserand <mylene.josserand@collabora.com>
> > ---
> >  arch/arm/mach-rockchip/rockchip.c | 45 +++++++++++++++++++++++++++++++
> >  include/soc/rockchip/revision.h   | 22 +++++++++++++++
> >  2 files changed, 67 insertions(+)
> >  create mode 100644 include/soc/rockchip/revision.h
> > 
> > diff --git a/arch/arm/mach-rockchip/rockchip.c b/arch/arm/mach-rockchip/rockchip.c
> > index f9797a2b5d0d..b907ba390093 100644
> > --- a/arch/arm/mach-rockchip/rockchip.c
> > +++ b/arch/arm/mach-rockchip/rockchip.c
> > @@ -9,12 +9,14 @@
> >  #include <linux/kernel.h>
> >  #include <linux/init.h>
> >  #include <linux/io.h>
> > +#include <linux/of_address.h>
> >  #include <linux/of_platform.h>
> >  #include <linux/irqchip.h>
> >  #include <linux/clk-provider.h>
> >  #include <linux/clocksource.h>
> >  #include <linux/mfd/syscon.h>
> >  #include <linux/regmap.h>
> > +#include <soc/rockchip/revision.h>
> >  #include <asm/mach/arch.h>
> >  #include <asm/mach/map.h>
> >  #include <asm/hardware/cache-l2x0.h>
> > @@ -22,6 +24,49 @@
> >  #include "pm.h"
> >  
> >  #define RK3288_TIMER6_7_PHYS 0xff810000
> > +#define RK3288_HDMI_REV_REG	0x04
> > +#define RK3288W_HDMI_REV	0x1A
> > +
> > +static const struct of_device_id rk3288_dt_hdmi_match[] __initconst = {
> > +	{ .compatible = "rockchip,rk3288-dw-hdmi" },
> > +	{ }
> > +};
> > +
> > +int rk3288_get_revision(void)
> > +{
> > +	static int revision = RK3288_SOC_REV_UNKNOWN;
> > +	struct device_node *dn;
> > +	void __iomem *hdmi_base;
> > +
> > +	if (revision != RK3288_SOC_REV_UNKNOWN)
> > +		return revision;
> > +
> > +	dn = of_find_matching_node(NULL, rk3288_dt_hdmi_match);
> > +	if (!dn) {
> > +		pr_err("%s: Couldn't find HDMI node\n", __func__);
> > +		return -EINVAL;
> > +	}
> > +
> > +	hdmi_base = of_iomap(dn, 0);
> > +	of_node_put(dn);
> > +
> > +	if (!hdmi_base) {
> > +		pr_err("%s: Couldn't map %pOF regs\n", __func__,
> > +		       hdmi_base);
> > +		return -ENXIO;
> > +	}
> > +
> > +	if (readl_relaxed(hdmi_base + RK3288_HDMI_REV_REG) ==
> > +	    RK3288W_HDMI_REV)
> > +		revision = RK3288_SOC_REV_RK3288W;
> > +	else
> > +		revision = RK3288_SOC_REV_RK3288;
> > +
> > +	iounmap(hdmi_base);
> > +
> > +	return revision;
> > +}
> > +EXPORT_SYMBOL(rk3288_get_revision);
> >  
> >  static void __init rockchip_timer_init(void)
> >  {
> > diff --git a/include/soc/rockchip/revision.h b/include/soc/rockchip/revision.h
> > new file mode 100644
> > index 000000000000..226419c60af0
> > --- /dev/null
> > +++ b/include/soc/rockchip/revision.h
> > @@ -0,0 +1,22 @@
> > +/* SPDX-License-Identifier: GPL-2.0-only */
> > +/*
> > + * Copyright 2020 Collabora
> > + */
> > +
> > +#ifndef __SOC_ROCKCHIP_REVISION_H__
> > +#define __SOC_ROCKCHIP_REVISION_H__
> > +
> > +enum rk3288_soc_revision {
> > +	RK3288_SOC_REV_UNKNOWN,
> > +	RK3288_SOC_REV_RK3288,
> > +	RK3288_SOC_REV_RK3288W,
> > +};
> > +
> > +int rk3288_get_revision(void);
> > +
> > +static inline bool soc_is_rk3288w(void)
> > +{
> > +	return rk3288_get_revision() == RK3288_SOC_REV_RK3288W;
> > +}
> > +
> > +#endif /* __SOC_ROCKCHIP_REVISION_H__ */
> > 
> 
> 
> 
>
Heiko Stuebner March 5, 2020, 12:51 a.m. UTC | #3
Hi Ezequiel,

Am Donnerstag, 5. März 2020, 01:03:30 CET schrieb Ezequiel Garcia:
> Hi Heiko,
> 
> On Wed, 2020-03-04 at 11:59 +0100, Heiko Stübner wrote:
> > Hi,
> > 
> > Am Montag, 2. März 2020, 16:57:02 CET schrieb Mylène Josserand:
> > > Determine which revision of rk3288 by checking the HDMI version.
> > > According to the Rockchip BSP kernel, on rk3288w, the HDMI
> > > revision equals 0x1A which is not the case for the rk3288 [1].
> > > 
> > > As these SOC have some differences, the new function
> > > 'soc_is_rk3288w' will help us to know on which revision
> > > we are.
> > 
> > what happened to just having a different compatible in the dts?
> > Aka doing a 
> > 
> > rk3288w.dtsi with
> > 
> > #include "rk3288.dtsi"
> > 
> > &cru {
> > 	compatible = "rockchip,rk3288w-cru";
> > }
> > 
> 
> I guess you have something like this in mind:
> 
> static void __init rk3288_clk_init(struct device_node *np)
> {
>         __rk3288_clk_init(np, RK3288_SOC_REV_RK3288W);
> }
> CLK_OF_DECLARE(rk3288_cru, "rockchip,rk3288-cru", rk3288_clk_init);
> 
> static void __init rk3288w_clk_init(struct device_node *np)
> {
>         __rk3288_clk_init(np, RK3288_SOC_REV_RK3288);
> }
> CLK_OF_DECLARE(rk3288_cru, "rockchip,rk3288w-cru", rk3288w_clk_init);
> 
> And the rest is mostly untouched, except the revision is
> no longer queried and is now passed by the DT?

Essentially yes, but I guess I was more thinking along the lines of
the rk3188/rk3066a/rk3188a (drivers/clk/rockchip/clk-rk3188.c)


> This would be cleaner for the kernel, with the obvious
> drawback being that you now have to maintain
> another DTS.

Right now we would end up with the pretty minimal devicetree
having just that cru. So not very invasive.


> This could be an inconvenience. I believe
> RK3288W is meant as a direct replacement for RK3288,
> so folks building products would expect to just use
> RK3288W, and not really bother with passing a
> different DTS or what not.

Not sure I follow. As below, I don't think boards will magically switch
between soc variants, so a boards devicetree should just include
the variant - especially as I don't really know how many
additional new boards we will see with it (rk3288 being quite old itself).


> > I somehow don't expect boards to just switch between soc variants
> > on the fly.
> > 
> 
> While I agree they are nasty, quirks like this
> are not uncommon.
> 
> > Also, doing things in mach-rockchip is not very future-proof:
> > 
> 
> There is actually no reason to keep this in mach-rockchip, right?
> 
> The quirk could be placed in other places. For instance,
> directly in the clock driver.

Mapping the hdmi controller inside the clock driver to read some "random"
register that hopefully indicates an (undocumented) distinction between soc
variants.

Somehow just having that minimal devicetree for the "w" sounds
way cleaner ;-) .


It's definitly cool to have support for the rk3288w but I don't like
adding hacks for something that is after all some sort of niche product.


Heiko


> > (1) having random soc-specific APIs spanning the kernel feels wrong,
> >     especially as at some point it might not be contained to our own special
> >     drivers like the cru. I cannot really see people being enthusiastic if
> >     something like this would be needed in say the core Analogix-DP bridge ;-)
> > (2) I guess the rk3288w will not be the last soc doing this and on arm64 you
> >     can't do it that way, as there is no mach-rockchip there
> > 
> > So my personal preference would really would be just a specific compatible
> > for affected ip blocks.
> > 
> > Heiko
> > 
> > > [1]:https://github.com/rockchip-linux/u-boot/blob/f992fe3334aa5090acb448261982628b5a3d37a5/arch/arm/include/asm/arch-rockchip/cpu.h#L30..L34
> > > 
> > > Signed-off-by: Mylène Josserand <mylene.josserand@collabora.com>
> > > ---
> > >  arch/arm/mach-rockchip/rockchip.c | 45 +++++++++++++++++++++++++++++++
> > >  include/soc/rockchip/revision.h   | 22 +++++++++++++++
> > >  2 files changed, 67 insertions(+)
> > >  create mode 100644 include/soc/rockchip/revision.h
> > > 
> > > diff --git a/arch/arm/mach-rockchip/rockchip.c b/arch/arm/mach-rockchip/rockchip.c
> > > index f9797a2b5d0d..b907ba390093 100644
> > > --- a/arch/arm/mach-rockchip/rockchip.c
> > > +++ b/arch/arm/mach-rockchip/rockchip.c
> > > @@ -9,12 +9,14 @@
> > >  #include <linux/kernel.h>
> > >  #include <linux/init.h>
> > >  #include <linux/io.h>
> > > +#include <linux/of_address.h>
> > >  #include <linux/of_platform.h>
> > >  #include <linux/irqchip.h>
> > >  #include <linux/clk-provider.h>
> > >  #include <linux/clocksource.h>
> > >  #include <linux/mfd/syscon.h>
> > >  #include <linux/regmap.h>
> > > +#include <soc/rockchip/revision.h>
> > >  #include <asm/mach/arch.h>
> > >  #include <asm/mach/map.h>
> > >  #include <asm/hardware/cache-l2x0.h>
> > > @@ -22,6 +24,49 @@
> > >  #include "pm.h"
> > >  
> > >  #define RK3288_TIMER6_7_PHYS 0xff810000
> > > +#define RK3288_HDMI_REV_REG	0x04
> > > +#define RK3288W_HDMI_REV	0x1A
> > > +
> > > +static const struct of_device_id rk3288_dt_hdmi_match[] __initconst = {
> > > +	{ .compatible = "rockchip,rk3288-dw-hdmi" },
> > > +	{ }
> > > +};
> > > +
> > > +int rk3288_get_revision(void)
> > > +{
> > > +	static int revision = RK3288_SOC_REV_UNKNOWN;
> > > +	struct device_node *dn;
> > > +	void __iomem *hdmi_base;
> > > +
> > > +	if (revision != RK3288_SOC_REV_UNKNOWN)
> > > +		return revision;
> > > +
> > > +	dn = of_find_matching_node(NULL, rk3288_dt_hdmi_match);
> > > +	if (!dn) {
> > > +		pr_err("%s: Couldn't find HDMI node\n", __func__);
> > > +		return -EINVAL;
> > > +	}
> > > +
> > > +	hdmi_base = of_iomap(dn, 0);
> > > +	of_node_put(dn);
> > > +
> > > +	if (!hdmi_base) {
> > > +		pr_err("%s: Couldn't map %pOF regs\n", __func__,
> > > +		       hdmi_base);
> > > +		return -ENXIO;
> > > +	}
> > > +
> > > +	if (readl_relaxed(hdmi_base + RK3288_HDMI_REV_REG) ==
> > > +	    RK3288W_HDMI_REV)
> > > +		revision = RK3288_SOC_REV_RK3288W;
> > > +	else
> > > +		revision = RK3288_SOC_REV_RK3288;
> > > +
> > > +	iounmap(hdmi_base);
> > > +
> > > +	return revision;
> > > +}
> > > +EXPORT_SYMBOL(rk3288_get_revision);
> > >  
> > >  static void __init rockchip_timer_init(void)
> > >  {
> > > diff --git a/include/soc/rockchip/revision.h b/include/soc/rockchip/revision.h
> > > new file mode 100644
> > > index 000000000000..226419c60af0
> > > --- /dev/null
> > > +++ b/include/soc/rockchip/revision.h
> > > @@ -0,0 +1,22 @@
> > > +/* SPDX-License-Identifier: GPL-2.0-only */
> > > +/*
> > > + * Copyright 2020 Collabora
> > > + */
> > > +
> > > +#ifndef __SOC_ROCKCHIP_REVISION_H__
> > > +#define __SOC_ROCKCHIP_REVISION_H__
> > > +
> > > +enum rk3288_soc_revision {
> > > +	RK3288_SOC_REV_UNKNOWN,
> > > +	RK3288_SOC_REV_RK3288,
> > > +	RK3288_SOC_REV_RK3288W,
> > > +};
> > > +
> > > +int rk3288_get_revision(void);
> > > +
> > > +static inline bool soc_is_rk3288w(void)
> > > +{
> > > +	return rk3288_get_revision() == RK3288_SOC_REV_RK3288W;
> > > +}
> > > +
> > > +#endif /* __SOC_ROCKCHIP_REVISION_H__ */
> > > 
> > 
> > 
> > 
> > 
> 
> 
>
Ezequiel Garcia March 5, 2020, 11:32 a.m. UTC | #4
On Thu, 2020-03-05 at 01:51 +0100, Heiko Stübner wrote:
> Hi Ezequiel,
> 
> Am Donnerstag, 5. März 2020, 01:03:30 CET schrieb Ezequiel Garcia:
> > Hi Heiko,
> > 
> > On Wed, 2020-03-04 at 11:59 +0100, Heiko Stübner wrote:
> > > Hi,
> > > 
> > > Am Montag, 2. März 2020, 16:57:02 CET schrieb Mylène Josserand:
> > > > Determine which revision of rk3288 by checking the HDMI version.
> > > > According to the Rockchip BSP kernel, on rk3288w, the HDMI
> > > > revision equals 0x1A which is not the case for the rk3288 [1].
> > > > 
> > > > As these SOC have some differences, the new function
> > > > 'soc_is_rk3288w' will help us to know on which revision
> > > > we are.
> > > 
> > > what happened to just having a different compatible in the dts?
> > > Aka doing a 
> > > 
> > > rk3288w.dtsi with
> > > 
> > > #include "rk3288.dtsi"
> > > 
> > > &cru {
> > > 	compatible = "rockchip,rk3288w-cru";
> > > }
> > > 
> > 
> > I guess you have something like this in mind:
> > 
> > static void __init rk3288_clk_init(struct device_node *np)
> > {
> >         __rk3288_clk_init(np, RK3288_SOC_REV_RK3288W);
> > }
> > CLK_OF_DECLARE(rk3288_cru, "rockchip,rk3288-cru", rk3288_clk_init);
> > 
> > static void __init rk3288w_clk_init(struct device_node *np)
> > {
> >         __rk3288_clk_init(np, RK3288_SOC_REV_RK3288);
> > }
> > CLK_OF_DECLARE(rk3288_cru, "rockchip,rk3288w-cru", rk3288w_clk_init);
> > 
> > And the rest is mostly untouched, except the revision is
> > no longer queried and is now passed by the DT?
> 
> Essentially yes, but I guess I was more thinking along the lines of
> the rk3188/rk3066a/rk3188a (drivers/clk/rockchip/clk-rk3188.c)
> 
> 
> > This would be cleaner for the kernel, with the obvious
> > drawback being that you now have to maintain
> > another DTS.
> 
> Right now we would end up with the pretty minimal devicetree
> having just that cru. So not very invasive.
> 
> 
> > This could be an inconvenience. I believe
> > RK3288W is meant as a direct replacement for RK3288,
> > so folks building products would expect to just use
> > RK3288W, and not really bother with passing a
> > different DTS or what not.
> 
> Not sure I follow. As below, I don't think boards will magically switch
> between soc variants, so a boards devicetree should just include
> the variant - especially as I don't really know how many
> additional new boards we will see with it (rk3288 being quite old itself).
> 

It's not about new boards, any company does sells some RK32888-based product,
will eventually want to produce some more.

If I understand correctly, RK3288W is the SoC that Rockchip is now offering,
and not RK3288 anymore.

So, if you have to produce another batch of _the same RK3288_ product,
you'll have to use RK3288W. In other words, they would "just switch"
between SoC variants.

In fact, such a case motivates these patches :-)

> 
> > > I somehow don't expect boards to just switch between soc variants
> > > on the fly.
> > > 
> > 
> > While I agree they are nasty, quirks like this
> > are not uncommon.
> > 
> > > Also, doing things in mach-rockchip is not very future-proof:
> > > 
> > 
> > There is actually no reason to keep this in mach-rockchip, right?
> > 
> > The quirk could be placed in other places. For instance,
> > directly in the clock driver.
> 
> Mapping the hdmi controller inside the clock driver to read some "random"
> register that hopefully indicates an (undocumented) distinction between soc
> variants.
> 
> Somehow just having that minimal devicetree for the "w" sounds
> way cleaner ;-) .
> 
> 
> It's definitly cool to have support for the rk3288w but I don't like
> adding hacks for something that is after all some sort of niche product.
> 

Why do you think it's a niche product?

Thanks,
Ezequiel

> 
> Heiko
> 
> 
> > > (1) having random soc-specific APIs spanning the kernel feels wrong,
> > >     especially as at some point it might not be contained to our own special
> > >     drivers like the cru. I cannot really see people being enthusiastic if
> > >     something like this would be needed in say the core Analogix-DP bridge ;-)
> > > (2) I guess the rk3288w will not be the last soc doing this and on arm64 you
> > >     can't do it that way, as there is no mach-rockchip there
> > > 
> > > So my personal preference would really would be just a specific compatible
> > > for affected ip blocks.
> > > 
> > > Heiko
> > > 
> > > > [1]:https://github.com/rockchip-linux/u-boot/blob/f992fe3334aa5090acb448261982628b5a3d37a5/arch/arm/include/asm/arch-rockchip/cpu.h#L30..L34
> > > > 
> > > > Signed-off-by: Mylène Josserand <mylene.josserand@collabora.com>
> > > > ---
> > > >  arch/arm/mach-rockchip/rockchip.c | 45 +++++++++++++++++++++++++++++++
> > > >  include/soc/rockchip/revision.h   | 22 +++++++++++++++
> > > >  2 files changed, 67 insertions(+)
> > > >  create mode 100644 include/soc/rockchip/revision.h
> > > > 
> > > > diff --git a/arch/arm/mach-rockchip/rockchip.c b/arch/arm/mach-rockchip/rockchip.c
> > > > index f9797a2b5d0d..b907ba390093 100644
> > > > --- a/arch/arm/mach-rockchip/rockchip.c
> > > > +++ b/arch/arm/mach-rockchip/rockchip.c
> > > > @@ -9,12 +9,14 @@
> > > >  #include <linux/kernel.h>
> > > >  #include <linux/init.h>
> > > >  #include <linux/io.h>
> > > > +#include <linux/of_address.h>
> > > >  #include <linux/of_platform.h>
> > > >  #include <linux/irqchip.h>
> > > >  #include <linux/clk-provider.h>
> > > >  #include <linux/clocksource.h>
> > > >  #include <linux/mfd/syscon.h>
> > > >  #include <linux/regmap.h>
> > > > +#include <soc/rockchip/revision.h>
> > > >  #include <asm/mach/arch.h>
> > > >  #include <asm/mach/map.h>
> > > >  #include <asm/hardware/cache-l2x0.h>
> > > > @@ -22,6 +24,49 @@
> > > >  #include "pm.h"
> > > >  
> > > >  #define RK3288_TIMER6_7_PHYS 0xff810000
> > > > +#define RK3288_HDMI_REV_REG	0x04
> > > > +#define RK3288W_HDMI_REV	0x1A
> > > > +
> > > > +static const struct of_device_id rk3288_dt_hdmi_match[] __initconst = {
> > > > +	{ .compatible = "rockchip,rk3288-dw-hdmi" },
> > > > +	{ }
> > > > +};
> > > > +
> > > > +int rk3288_get_revision(void)
> > > > +{
> > > > +	static int revision = RK3288_SOC_REV_UNKNOWN;
> > > > +	struct device_node *dn;
> > > > +	void __iomem *hdmi_base;
> > > > +
> > > > +	if (revision != RK3288_SOC_REV_UNKNOWN)
> > > > +		return revision;
> > > > +
> > > > +	dn = of_find_matching_node(NULL, rk3288_dt_hdmi_match);
> > > > +	if (!dn) {
> > > > +		pr_err("%s: Couldn't find HDMI node\n", __func__);
> > > > +		return -EINVAL;
> > > > +	}
> > > > +
> > > > +	hdmi_base = of_iomap(dn, 0);
> > > > +	of_node_put(dn);
> > > > +
> > > > +	if (!hdmi_base) {
> > > > +		pr_err("%s: Couldn't map %pOF regs\n", __func__,
> > > > +		       hdmi_base);
> > > > +		return -ENXIO;
> > > > +	}
> > > > +
> > > > +	if (readl_relaxed(hdmi_base + RK3288_HDMI_REV_REG) ==
> > > > +	    RK3288W_HDMI_REV)
> > > > +		revision = RK3288_SOC_REV_RK3288W;
> > > > +	else
> > > > +		revision = RK3288_SOC_REV_RK3288;
> > > > +
> > > > +	iounmap(hdmi_base);
> > > > +
> > > > +	return revision;
> > > > +}
> > > > +EXPORT_SYMBOL(rk3288_get_revision);
> > > >  
> > > >  static void __init rockchip_timer_init(void)
> > > >  {
> > > > diff --git a/include/soc/rockchip/revision.h b/include/soc/rockchip/revision.h
> > > > new file mode 100644
> > > > index 000000000000..226419c60af0
> > > > --- /dev/null
> > > > +++ b/include/soc/rockchip/revision.h
> > > > @@ -0,0 +1,22 @@
> > > > +/* SPDX-License-Identifier: GPL-2.0-only */
> > > > +/*
> > > > + * Copyright 2020 Collabora
> > > > + */
> > > > +
> > > > +#ifndef __SOC_ROCKCHIP_REVISION_H__
> > > > +#define __SOC_ROCKCHIP_REVISION_H__
> > > > +
> > > > +enum rk3288_soc_revision {
> > > > +	RK3288_SOC_REV_UNKNOWN,
> > > > +	RK3288_SOC_REV_RK3288,
> > > > +	RK3288_SOC_REV_RK3288W,
> > > > +};
> > > > +
> > > > +int rk3288_get_revision(void);
> > > > +
> > > > +static inline bool soc_is_rk3288w(void)
> > > > +{
> > > > +	return rk3288_get_revision() == RK3288_SOC_REV_RK3288W;
> > > > +}
> > > > +
> > > > +#endif /* __SOC_ROCKCHIP_REVISION_H__ */
> > > > 
> > > 
> > > 
> > > 
> > 
> > 
> 
> 
>
Ezequiel Garcia March 5, 2020, 11:35 a.m. UTC | #5
(Adding Kever to the loop)

On Thu, 2020-03-05 at 08:32 -0300, Ezequiel Garcia wrote:
> On Thu, 2020-03-05 at 01:51 +0100, Heiko Stübner wrote:
> > Hi Ezequiel,
> > 
> > Am Donnerstag, 5. März 2020, 01:03:30 CET schrieb Ezequiel Garcia:
> > > Hi Heiko,
> > > 
> > > On Wed, 2020-03-04 at 11:59 +0100, Heiko Stübner wrote:
> > > > Hi,
> > > > 
> > > > Am Montag, 2. März 2020, 16:57:02 CET schrieb Mylène Josserand:
> > > > > Determine which revision of rk3288 by checking the HDMI version.
> > > > > According to the Rockchip BSP kernel, on rk3288w, the HDMI
> > > > > revision equals 0x1A which is not the case for the rk3288 [1].
> > > > > 
> > > > > As these SOC have some differences, the new function
> > > > > 'soc_is_rk3288w' will help us to know on which revision
> > > > > we are.
> > > > 
> > > > what happened to just having a different compatible in the dts?
> > > > Aka doing a 
> > > > 
> > > > rk3288w.dtsi with
> > > > 
> > > > #include "rk3288.dtsi"
> > > > 
> > > > &cru {
> > > > 	compatible = "rockchip,rk3288w-cru";
> > > > }
> > > > 
> > > 
> > > I guess you have something like this in mind:
> > > 
> > > static void __init rk3288_clk_init(struct device_node *np)
> > > {
> > >         __rk3288_clk_init(np, RK3288_SOC_REV_RK3288W);
> > > }
> > > CLK_OF_DECLARE(rk3288_cru, "rockchip,rk3288-cru", rk3288_clk_init);
> > > 
> > > static void __init rk3288w_clk_init(struct device_node *np)
> > > {
> > >         __rk3288_clk_init(np, RK3288_SOC_REV_RK3288);
> > > }
> > > CLK_OF_DECLARE(rk3288_cru, "rockchip,rk3288w-cru", rk3288w_clk_init);
> > > 
> > > And the rest is mostly untouched, except the revision is
> > > no longer queried and is now passed by the DT?
> > 
> > Essentially yes, but I guess I was more thinking along the lines of
> > the rk3188/rk3066a/rk3188a (drivers/clk/rockchip/clk-rk3188.c)
> > 
> > 
> > > This would be cleaner for the kernel, with the obvious
> > > drawback being that you now have to maintain
> > > another DTS.
> > 
> > Right now we would end up with the pretty minimal devicetree
> > having just that cru. So not very invasive.
> > 
> > 
> > > This could be an inconvenience. I believe
> > > RK3288W is meant as a direct replacement for RK3288,
> > > so folks building products would expect to just use
> > > RK3288W, and not really bother with passing a
> > > different DTS or what not.
> > 
> > Not sure I follow. As below, I don't think boards will magically switch
> > between soc variants, so a boards devicetree should just include
> > the variant - especially as I don't really know how many
> > additional new boards we will see with it (rk3288 being quite old itself).
> > 
> 
> It's not about new boards, any company does sells some RK32888-based product,
> will eventually want to produce some more.
> 
> If I understand correctly, RK3288W is the SoC that Rockchip is now offering,
> and not RK3288 anymore.
> 
> So, if you have to produce another batch of _the same RK3288_ product,
> you'll have to use RK3288W. In other words, they would "just switch"
> between SoC variants.
> 
> In fact, such a case motivates these patches :-)
> 
> > > > I somehow don't expect boards to just switch between soc variants
> > > > on the fly.
> > > > 
> > > 
> > > While I agree they are nasty, quirks like this
> > > are not uncommon.
> > > 
> > > > Also, doing things in mach-rockchip is not very future-proof:
> > > > 
> > > 
> > > There is actually no reason to keep this in mach-rockchip, right?
> > > 
> > > The quirk could be placed in other places. For instance,
> > > directly in the clock driver.
> > 
> > Mapping the hdmi controller inside the clock driver to read some "random"
> > register that hopefully indicates an (undocumented) distinction between soc
> > variants.
> > 
> > Somehow just having that minimal devicetree for the "w" sounds
> > way cleaner ;-) .
> > 
> > 
> > It's definitly cool to have support for the rk3288w but I don't like
> > adding hacks for something that is after all some sort of niche product.
> > 
> 
> Why do you think it's a niche product?
> 
> Thanks,
> Ezequiel
> 
> > Heiko
> > 
> > 
> > > > (1) having random soc-specific APIs spanning the kernel feels wrong,
> > > >     especially as at some point it might not be contained to our own special
> > > >     drivers like the cru. I cannot really see people being enthusiastic if
> > > >     something like this would be needed in say the core Analogix-DP bridge ;-)
> > > > (2) I guess the rk3288w will not be the last soc doing this and on arm64 you
> > > >     can't do it that way, as there is no mach-rockchip there
> > > > 
> > > > So my personal preference would really would be just a specific compatible
> > > > for affected ip blocks.
> > > > 
> > > > Heiko
> > > > 
> > > > > [1]:https://github.com/rockchip-linux/u-boot/blob/f992fe3334aa5090acb448261982628b5a3d37a5/arch/arm/include/asm/arch-rockchip/cpu.h#L30..L34
> > > > > 
> > > > > Signed-off-by: Mylène Josserand <mylene.josserand@collabora.com>
> > > > > ---
> > > > >  arch/arm/mach-rockchip/rockchip.c | 45 +++++++++++++++++++++++++++++++
> > > > >  include/soc/rockchip/revision.h   | 22 +++++++++++++++
> > > > >  2 files changed, 67 insertions(+)
> > > > >  create mode 100644 include/soc/rockchip/revision.h
> > > > > 
> > > > > diff --git a/arch/arm/mach-rockchip/rockchip.c b/arch/arm/mach-rockchip/rockchip.c
> > > > > index f9797a2b5d0d..b907ba390093 100644
> > > > > --- a/arch/arm/mach-rockchip/rockchip.c
> > > > > +++ b/arch/arm/mach-rockchip/rockchip.c
> > > > > @@ -9,12 +9,14 @@
> > > > >  #include <linux/kernel.h>
> > > > >  #include <linux/init.h>
> > > > >  #include <linux/io.h>
> > > > > +#include <linux/of_address.h>
> > > > >  #include <linux/of_platform.h>
> > > > >  #include <linux/irqchip.h>
> > > > >  #include <linux/clk-provider.h>
> > > > >  #include <linux/clocksource.h>
> > > > >  #include <linux/mfd/syscon.h>
> > > > >  #include <linux/regmap.h>
> > > > > +#include <soc/rockchip/revision.h>
> > > > >  #include <asm/mach/arch.h>
> > > > >  #include <asm/mach/map.h>
> > > > >  #include <asm/hardware/cache-l2x0.h>
> > > > > @@ -22,6 +24,49 @@
> > > > >  #include "pm.h"
> > > > >  
> > > > >  #define RK3288_TIMER6_7_PHYS 0xff810000
> > > > > +#define RK3288_HDMI_REV_REG	0x04
> > > > > +#define RK3288W_HDMI_REV	0x1A
> > > > > +
> > > > > +static const struct of_device_id rk3288_dt_hdmi_match[] __initconst = {
> > > > > +	{ .compatible = "rockchip,rk3288-dw-hdmi" },
> > > > > +	{ }
> > > > > +};
> > > > > +
> > > > > +int rk3288_get_revision(void)
> > > > > +{
> > > > > +	static int revision = RK3288_SOC_REV_UNKNOWN;
> > > > > +	struct device_node *dn;
> > > > > +	void __iomem *hdmi_base;
> > > > > +
> > > > > +	if (revision != RK3288_SOC_REV_UNKNOWN)
> > > > > +		return revision;
> > > > > +
> > > > > +	dn = of_find_matching_node(NULL, rk3288_dt_hdmi_match);
> > > > > +	if (!dn) {
> > > > > +		pr_err("%s: Couldn't find HDMI node\n", __func__);
> > > > > +		return -EINVAL;
> > > > > +	}
> > > > > +
> > > > > +	hdmi_base = of_iomap(dn, 0);
> > > > > +	of_node_put(dn);
> > > > > +
> > > > > +	if (!hdmi_base) {
> > > > > +		pr_err("%s: Couldn't map %pOF regs\n", __func__,
> > > > > +		       hdmi_base);
> > > > > +		return -ENXIO;
> > > > > +	}
> > > > > +
> > > > > +	if (readl_relaxed(hdmi_base + RK3288_HDMI_REV_REG) ==
> > > > > +	    RK3288W_HDMI_REV)
> > > > > +		revision = RK3288_SOC_REV_RK3288W;
> > > > > +	else
> > > > > +		revision = RK3288_SOC_REV_RK3288;
> > > > > +
> > > > > +	iounmap(hdmi_base);
> > > > > +
> > > > > +	return revision;
> > > > > +}
> > > > > +EXPORT_SYMBOL(rk3288_get_revision);
> > > > >  
> > > > >  static void __init rockchip_timer_init(void)
> > > > >  {
> > > > > diff --git a/include/soc/rockchip/revision.h b/include/soc/rockchip/revision.h
> > > > > new file mode 100644
> > > > > index 000000000000..226419c60af0
> > > > > --- /dev/null
> > > > > +++ b/include/soc/rockchip/revision.h
> > > > > @@ -0,0 +1,22 @@
> > > > > +/* SPDX-License-Identifier: GPL-2.0-only */
> > > > > +/*
> > > > > + * Copyright 2020 Collabora
> > > > > + */
> > > > > +
> > > > > +#ifndef __SOC_ROCKCHIP_REVISION_H__
> > > > > +#define __SOC_ROCKCHIP_REVISION_H__
> > > > > +
> > > > > +enum rk3288_soc_revision {
> > > > > +	RK3288_SOC_REV_UNKNOWN,
> > > > > +	RK3288_SOC_REV_RK3288,
> > > > > +	RK3288_SOC_REV_RK3288W,
> > > > > +};
> > > > > +
> > > > > +int rk3288_get_revision(void);
> > > > > +
> > > > > +static inline bool soc_is_rk3288w(void)
> > > > > +{
> > > > > +	return rk3288_get_revision() == RK3288_SOC_REV_RK3288W;
> > > > > +}
> > > > > +
> > > > > +#endif /* __SOC_ROCKCHIP_REVISION_H__ */
> > > > > 
> > > > 
> > > > 
> > 
> > 
> 
>
Kever Yang March 6, 2020, 2:44 a.m. UTC | #6
Hi Ezequiel,


On 2020/3/5 下午7:35, Ezequiel Garcia wrote:
> (Adding Kever to the loop)
>
> On Thu, 2020-03-05 at 08:32 -0300, Ezequiel Garcia wrote:
>> On Thu, 2020-03-05 at 01:51 +0100, Heiko Stübner wrote:
>>> Hi Ezequiel,
>>>
>>> Am Donnerstag, 5. März 2020, 01:03:30 CET schrieb Ezequiel Garcia:
>>>> Hi Heiko,
>>>>
>>>> On Wed, 2020-03-04 at 11:59 +0100, Heiko Stübner wrote:
>>>>> Hi,
>>>>>
>>>>> Am Montag, 2. März 2020, 16:57:02 CET schrieb Mylène Josserand:
>>>>>> Determine which revision of rk3288 by checking the HDMI version.
>>>>>> According to the Rockchip BSP kernel, on rk3288w, the HDMI
>>>>>> revision equals 0x1A which is not the case for the rk3288 [1].
>>>>>>
>>>>>> As these SOC have some differences, the new function
>>>>>> 'soc_is_rk3288w' will help us to know on which revision
>>>>>> we are.
>>>>> what happened to just having a different compatible in the dts?
>>>>> Aka doing a
>>>>>
>>>>> rk3288w.dtsi with
>>>>>
>>>>> #include "rk3288.dtsi"
>>>>>
>>>>> &cru {
>>>>> 	compatible = "rockchip,rk3288w-cru";
>>>>> }
>>>>>
>>>> I guess you have something like this in mind:
>>>>
>>>> static void __init rk3288_clk_init(struct device_node *np)
>>>> {
>>>>          __rk3288_clk_init(np, RK3288_SOC_REV_RK3288W);
>>>> }
>>>> CLK_OF_DECLARE(rk3288_cru, "rockchip,rk3288-cru", rk3288_clk_init);
>>>>
>>>> static void __init rk3288w_clk_init(struct device_node *np)
>>>> {
>>>>          __rk3288_clk_init(np, RK3288_SOC_REV_RK3288);
>>>> }
>>>> CLK_OF_DECLARE(rk3288_cru, "rockchip,rk3288w-cru", rk3288w_clk_init);
>>>>
>>>> And the rest is mostly untouched, except the revision is
>>>> no longer queried and is now passed by the DT?
>>> Essentially yes, but I guess I was more thinking along the lines of
>>> the rk3188/rk3066a/rk3188a (drivers/clk/rockchip/clk-rk3188.c)
>>>
>>>
>>>> This would be cleaner for the kernel, with the obvious
>>>> drawback being that you now have to maintain
>>>> another DTS.
>>> Right now we would end up with the pretty minimal devicetree
>>> having just that cru. So not very invasive.
>>>
>>>
>>>> This could be an inconvenience. I believe
>>>> RK3288W is meant as a direct replacement for RK3288,
>>>> so folks building products would expect to just use
>>>> RK3288W, and not really bother with passing a
>>>> different DTS or what not.
>>> Not sure I follow. As below, I don't think boards will magically switch
>>> between soc variants, so a boards devicetree should just include
>>> the variant - especially as I don't really know how many
>>> additional new boards we will see with it (rk3288 being quite old itself).
>>>
>> It's not about new boards, any company does sells some RK32888-based product,
>> will eventually want to produce some more.
>>
>> If I understand correctly, RK3288W is the SoC that Rockchip is now offering,
>> and not RK3288 anymore.


No, the RK3288 will continue to supply to the legacy projects which may 
have a long contract with Rockchip,

and RK3288W is the recommend to use in all new project.

>>
>> So, if you have to produce another batch of _the same RK3288_ product,
>> you'll have to use RK3288W. In other words, they would "just switch"
>> between SoC variants.
>>
>> In fact, such a case motivates these patches :-)
>>
>>>>> I somehow don't expect boards to just switch between soc variants
>>>>> on the fly.
>>>>>
>>>> While I agree they are nasty, quirks like this
>>>> are not uncommon.
>>>>
>>>>> Also, doing things in mach-rockchip is not very future-proof:
>>>>>
>>>> There is actually no reason to keep this in mach-rockchip, right?
>>>>
>>>> The quirk could be placed in other places. For instance,
>>>> directly in the clock driver.
>>> Mapping the hdmi controller inside the clock driver to read some "random"
>>> register that hopefully indicates an (undocumented) distinction between soc
>>> variants.
>>>
>>> Somehow just having that minimal devicetree for the "w" sounds
>>> way cleaner ;-) .

I agree with Heiko on this.

What Rockchip done is:

- kernel is using "rockchip,rk3288w" compatible to identify rk3288w, 
which is clean in kernel;

- kernel evb dts do not have compatible "rockchip,rk3288w" for we would 
like to identify it dynamic in bootloader;

- We use U-Boot to identify the rk3288w with HDMI reg value, and pass it 
to kernel via modify the

    dtb pass to kernel, so that we can support all kind of rockchip 
customer projects with any kind of rk3288;

- For upstream kernel, it make sense to add "rockchip,rk3288w" in board 
dts for which using rk3288w SoC.


Thanks,

- Kever

>>>
>>>
>>> It's definitly cool to have support for the rk3288w but I don't like
>>> adding hacks for something that is after all some sort of niche product.
>>>
>> Why do you think it's a niche product?
>>
>> Thanks,
>> Ezequiel
>>
>>> Heiko
>>>
>>>
>>>>> (1) having random soc-specific APIs spanning the kernel feels wrong,
>>>>>      especially as at some point it might not be contained to our own special
>>>>>      drivers like the cru. I cannot really see people being enthusiastic if
>>>>>      something like this would be needed in say the core Analogix-DP bridge ;-)
>>>>> (2) I guess the rk3288w will not be the last soc doing this and on arm64 you
>>>>>      can't do it that way, as there is no mach-rockchip there
>>>>>
>>>>> So my personal preference would really would be just a specific compatible
>>>>> for affected ip blocks.
>>>>>
>>>>> Heiko
>>>>>
>>>>>> [1]:https://github.com/rockchip-linux/u-boot/blob/f992fe3334aa5090acb448261982628b5a3d37a5/arch/arm/include/asm/arch-rockchip/cpu.h#L30..L34
>>>>>>
>>>>>> Signed-off-by: Mylène Josserand <mylene.josserand@collabora.com>
>>>>>> ---
>>>>>>   arch/arm/mach-rockchip/rockchip.c | 45 +++++++++++++++++++++++++++++++
>>>>>>   include/soc/rockchip/revision.h   | 22 +++++++++++++++
>>>>>>   2 files changed, 67 insertions(+)
>>>>>>   create mode 100644 include/soc/rockchip/revision.h
>>>>>>
>>>>>> diff --git a/arch/arm/mach-rockchip/rockchip.c b/arch/arm/mach-rockchip/rockchip.c
>>>>>> index f9797a2b5d0d..b907ba390093 100644
>>>>>> --- a/arch/arm/mach-rockchip/rockchip.c
>>>>>> +++ b/arch/arm/mach-rockchip/rockchip.c
>>>>>> @@ -9,12 +9,14 @@
>>>>>>   #include <linux/kernel.h>
>>>>>>   #include <linux/init.h>
>>>>>>   #include <linux/io.h>
>>>>>> +#include <linux/of_address.h>
>>>>>>   #include <linux/of_platform.h>
>>>>>>   #include <linux/irqchip.h>
>>>>>>   #include <linux/clk-provider.h>
>>>>>>   #include <linux/clocksource.h>
>>>>>>   #include <linux/mfd/syscon.h>
>>>>>>   #include <linux/regmap.h>
>>>>>> +#include <soc/rockchip/revision.h>
>>>>>>   #include <asm/mach/arch.h>
>>>>>>   #include <asm/mach/map.h>
>>>>>>   #include <asm/hardware/cache-l2x0.h>
>>>>>> @@ -22,6 +24,49 @@
>>>>>>   #include "pm.h"
>>>>>>   
>>>>>>   #define RK3288_TIMER6_7_PHYS 0xff810000
>>>>>> +#define RK3288_HDMI_REV_REG	0x04
>>>>>> +#define RK3288W_HDMI_REV	0x1A
>>>>>> +
>>>>>> +static const struct of_device_id rk3288_dt_hdmi_match[] __initconst = {
>>>>>> +	{ .compatible = "rockchip,rk3288-dw-hdmi" },
>>>>>> +	{ }
>>>>>> +};
>>>>>> +
>>>>>> +int rk3288_get_revision(void)
>>>>>> +{
>>>>>> +	static int revision = RK3288_SOC_REV_UNKNOWN;
>>>>>> +	struct device_node *dn;
>>>>>> +	void __iomem *hdmi_base;
>>>>>> +
>>>>>> +	if (revision != RK3288_SOC_REV_UNKNOWN)
>>>>>> +		return revision;
>>>>>> +
>>>>>> +	dn = of_find_matching_node(NULL, rk3288_dt_hdmi_match);
>>>>>> +	if (!dn) {
>>>>>> +		pr_err("%s: Couldn't find HDMI node\n", __func__);
>>>>>> +		return -EINVAL;
>>>>>> +	}
>>>>>> +
>>>>>> +	hdmi_base = of_iomap(dn, 0);
>>>>>> +	of_node_put(dn);
>>>>>> +
>>>>>> +	if (!hdmi_base) {
>>>>>> +		pr_err("%s: Couldn't map %pOF regs\n", __func__,
>>>>>> +		       hdmi_base);
>>>>>> +		return -ENXIO;
>>>>>> +	}
>>>>>> +
>>>>>> +	if (readl_relaxed(hdmi_base + RK3288_HDMI_REV_REG) ==
>>>>>> +	    RK3288W_HDMI_REV)
>>>>>> +		revision = RK3288_SOC_REV_RK3288W;
>>>>>> +	else
>>>>>> +		revision = RK3288_SOC_REV_RK3288;
>>>>>> +
>>>>>> +	iounmap(hdmi_base);
>>>>>> +
>>>>>> +	return revision;
>>>>>> +}
>>>>>> +EXPORT_SYMBOL(rk3288_get_revision);
>>>>>>   
>>>>>>   static void __init rockchip_timer_init(void)
>>>>>>   {
>>>>>> diff --git a/include/soc/rockchip/revision.h b/include/soc/rockchip/revision.h
>>>>>> new file mode 100644
>>>>>> index 000000000000..226419c60af0
>>>>>> --- /dev/null
>>>>>> +++ b/include/soc/rockchip/revision.h
>>>>>> @@ -0,0 +1,22 @@
>>>>>> +/* SPDX-License-Identifier: GPL-2.0-only */
>>>>>> +/*
>>>>>> + * Copyright 2020 Collabora
>>>>>> + */
>>>>>> +
>>>>>> +#ifndef __SOC_ROCKCHIP_REVISION_H__
>>>>>> +#define __SOC_ROCKCHIP_REVISION_H__
>>>>>> +
>>>>>> +enum rk3288_soc_revision {
>>>>>> +	RK3288_SOC_REV_UNKNOWN,
>>>>>> +	RK3288_SOC_REV_RK3288,
>>>>>> +	RK3288_SOC_REV_RK3288W,
>>>>>> +};
>>>>>> +
>>>>>> +int rk3288_get_revision(void);
>>>>>> +
>>>>>> +static inline bool soc_is_rk3288w(void)
>>>>>> +{
>>>>>> +	return rk3288_get_revision() == RK3288_SOC_REV_RK3288W;
>>>>>> +}
>>>>>> +
>>>>>> +#endif /* __SOC_ROCKCHIP_REVISION_H__ */
>>>>>>
>>>>>
>>>
>>
>
>
>
>
Ezequiel Garcia March 6, 2020, 10:30 a.m. UTC | #7
On Fri, 2020-03-06 at 10:44 +0800, Kever Yang wrote:
> Hi Ezequiel,
> 
> 
> On 2020/3/5 下午7:35, Ezequiel Garcia wrote:
> > (Adding Kever to the loop)
> > 
> > On Thu, 2020-03-05 at 08:32 -0300, Ezequiel Garcia wrote:
> > > On Thu, 2020-03-05 at 01:51 +0100, Heiko Stübner wrote:
> > > > Hi Ezequiel,
> > > > 
> > > > Am Donnerstag, 5. März 2020, 01:03:30 CET schrieb Ezequiel Garcia:
> > > > > Hi Heiko,
> > > > > 
> > > > > On Wed, 2020-03-04 at 11:59 +0100, Heiko Stübner wrote:
> > > > > > Hi,
> > > > > > 
> > > > > > Am Montag, 2. März 2020, 16:57:02 CET schrieb Mylène Josserand:
> > > > > > > Determine which revision of rk3288 by checking the HDMI version.
> > > > > > > According to the Rockchip BSP kernel, on rk3288w, the HDMI
> > > > > > > revision equals 0x1A which is not the case for the rk3288 [1].
> > > > > > > 
> > > > > > > As these SOC have some differences, the new function
> > > > > > > 'soc_is_rk3288w' will help us to know on which revision
> > > > > > > we are.
> > > > > > what happened to just having a different compatible in the dts?
> > > > > > Aka doing a
> > > > > > 
> > > > > > rk3288w.dtsi with
> > > > > > 
> > > > > > #include "rk3288.dtsi"
> > > > > > 
> > > > > > &cru {
> > > > > > 	compatible = "rockchip,rk3288w-cru";
> > > > > > }
> > > > > > 
> > > > > I guess you have something like this in mind:
> > > > > 
> > > > > static void __init rk3288_clk_init(struct device_node *np)
> > > > > {
> > > > >          __rk3288_clk_init(np, RK3288_SOC_REV_RK3288W);
> > > > > }
> > > > > CLK_OF_DECLARE(rk3288_cru, "rockchip,rk3288-cru", rk3288_clk_init);
> > > > > 
> > > > > static void __init rk3288w_clk_init(struct device_node *np)
> > > > > {
> > > > >          __rk3288_clk_init(np, RK3288_SOC_REV_RK3288);
> > > > > }
> > > > > CLK_OF_DECLARE(rk3288_cru, "rockchip,rk3288w-cru", rk3288w_clk_init);
> > > > > 
> > > > > And the rest is mostly untouched, except the revision is
> > > > > no longer queried and is now passed by the DT?
> > > > Essentially yes, but I guess I was more thinking along the lines of
> > > > the rk3188/rk3066a/rk3188a (drivers/clk/rockchip/clk-rk3188.c)
> > > > 
> > > > 
> > > > > This would be cleaner for the kernel, with the obvious
> > > > > drawback being that you now have to maintain
> > > > > another DTS.
> > > > Right now we would end up with the pretty minimal devicetree
> > > > having just that cru. So not very invasive.
> > > > 
> > > > 
> > > > > This could be an inconvenience. I believe
> > > > > RK3288W is meant as a direct replacement for RK3288,
> > > > > so folks building products would expect to just use
> > > > > RK3288W, and not really bother with passing a
> > > > > different DTS or what not.
> > > > Not sure I follow. As below, I don't think boards will magically switch
> > > > between soc variants, so a boards devicetree should just include
> > > > the variant - especially as I don't really know how many
> > > > additional new boards we will see with it (rk3288 being quite old itself).
> > > > 
> > > It's not about new boards, any company does sells some RK32888-based product,
> > > will eventually want to produce some more.
> > > 
> > > If I understand correctly, RK3288W is the SoC that Rockchip is now offering,
> > > and not RK3288 anymore.
> 
> No, the RK3288 will continue to supply to the legacy projects which may 
> have a long contract with Rockchip,
> 
> and RK3288W is the recommend to use in all new project.
> 

I guess this means that if a company not having a long contract
wants to keep producing an RK3288-based product, it will have to
resort to RK3288W.

And IIRC, it's meant to be a direct replacement.
 
> > > So, if you have to produce another batch of _the same RK3288_ product,
> > > you'll have to use RK3288W. In other words, they would "just switch"
> > > between SoC variants.
> > > 
> > > In fact, such a case motivates these patches :-)
> > > 
> > > > > > I somehow don't expect boards to just switch between soc variants
> > > > > > on the fly.
> > > > > > 
> > > > > While I agree they are nasty, quirks like this
> > > > > are not uncommon.
> > > > > 
> > > > > > Also, doing things in mach-rockchip is not very future-proof:
> > > > > > 
> > > > > There is actually no reason to keep this in mach-rockchip, right?
> > > > > 
> > > > > The quirk could be placed in other places. For instance,
> > > > > directly in the clock driver.
> > > > Mapping the hdmi controller inside the clock driver to read some "random"
> > > > register that hopefully indicates an (undocumented) distinction between soc
> > > > variants.
> > > > 
> > > > Somehow just having that minimal devicetree for the "w" sounds
> > > > way cleaner ;-) .
> 
> I agree with Heiko on this.
> 
> What Rockchip done is:
> 
> - kernel is using "rockchip,rk3288w" compatible to identify rk3288w, 
> which is clean in kernel;
> 
> - kernel evb dts do not have compatible "rockchip,rk3288w" for we would 
> like to identify it dynamic in bootloader;
> 
> - We use U-Boot to identify the rk3288w with HDMI reg value, and pass it 
> to kernel via modify the
> 
>     dtb pass to kernel, so that we can support all kind of rockchip 
> customer projects with any kind of rk3288;
> 
> - For upstream kernel, it make sense to add "rockchip,rk3288w" in board 
> dts for which using rk3288w SoC.
> 

So you proposing to move this revision detection code
from the kernel to all the bootloaders (U-Boot is not the
only one, right?).

I understand that bootloaders are maybe less strict
to quirks like this, but OTOH this approach seems like
just movint things around, plus requiring now to update
two components, instead of just one.

And also, are we sure the bootloaders maintainers
will accept the quirk?

Thanks,
Ezequiel
Geert Uytterhoeven March 6, 2020, 10:45 a.m. UTC | #8
Hi Heiko,

On Wed, Mar 4, 2020 at 12:00 PM Heiko Stübner <heiko@sntech.de> wrote:
> Am Montag, 2. März 2020, 16:57:02 CET schrieb Mylène Josserand:
> > Determine which revision of rk3288 by checking the HDMI version.
> > According to the Rockchip BSP kernel, on rk3288w, the HDMI
> > revision equals 0x1A which is not the case for the rk3288 [1].
> >
> > As these SOC have some differences, the new function
> > 'soc_is_rk3288w' will help us to know on which revision
> > we are.
>
> what happened to just having a different compatible in the dts?
> Aka doing a
>
> rk3288w.dtsi with
>
> #include "rk3288.dtsi"
>
> &cru {
>         compatible = "rockchip,rk3288w-cru";
> }
>
> I somehow don't expect boards to just switch between soc variants
> on the fly.
>
> Also, doing things in mach-rockchip is not very future-proof:
>
> (1) having random soc-specific APIs spanning the kernel feels wrong,
>     especially as at some point it might not be contained to our own special
>     drivers like the cru. I cannot really see people being enthusiastic if
>     something like this would be needed in say the core Analogix-DP bridge ;-)

Indeed.  You're better of registering an soc_device_attribute using
soc_device_register(), after which any driver can use soc_device_match()
to differentiate based on the SoC revision.

> (2) I guess the rk3288w will not be the last soc doing this and on arm64 you
>     can't do it that way, as there is no mach-rockchip there

There's drivers/soc/rockchip ;-)

> So my personal preference would really would be just a specific compatible
> for affected ip blocks.

Doing that only for affected IP blocks may miss integration differences.
Of course, you can always resort to soc_device_match() to handle those...

Gr{oetje,eeting}s,

                        Geert
Mylene Josserand March 26, 2020, 1:50 p.m. UTC | #9
Hello everyone,

Thank you for all these feedback and discussion about my patches.

On 3/6/20 11:45 AM, Geert Uytterhoeven wrote:
> Hi Heiko,
> 
> On Wed, Mar 4, 2020 at 12:00 PM Heiko Stübner <heiko@sntech.de> wrote:
>> Am Montag, 2. März 2020, 16:57:02 CET schrieb Mylène Josserand:
>>> Determine which revision of rk3288 by checking the HDMI version.
>>> According to the Rockchip BSP kernel, on rk3288w, the HDMI
>>> revision equals 0x1A which is not the case for the rk3288 [1].
>>>
>>> As these SOC have some differences, the new function
>>> 'soc_is_rk3288w' will help us to know on which revision
>>> we are.
>>
>> what happened to just having a different compatible in the dts?
>> Aka doing a
>>
>> rk3288w.dtsi with
>>
>> #include "rk3288.dtsi"
>>
>> &cru {
>>          compatible = "rockchip,rk3288w-cru";
>> }
>>
>> I somehow don't expect boards to just switch between soc variants
>> on the fly.
>>
>> Also, doing things in mach-rockchip is not very future-proof:
>>
>> (1) having random soc-specific APIs spanning the kernel feels wrong,
>>      especially as at some point it might not be contained to our own special
>>      drivers like the cru. I cannot really see people being enthusiastic if
>>      something like this would be needed in say the core Analogix-DP bridge ;-)
> 
> Indeed.  You're better of registering an soc_device_attribute using
> soc_device_register(), after which any driver can use soc_device_match()
> to differentiate based on the SoC revision.

Thank you for this suggestion. The issue is that clocks are registered 
at an early stage of the boot so using initcalls is too late for the 
clock differentiation :(

> 
>> (2) I guess the rk3288w will not be the last soc doing this and on arm64 you
>>      can't do it that way, as there is no mach-rockchip there
> 
> There's drivers/soc/rockchip ;-)
> 
>> So my personal preference would really would be just a specific compatible
>> for affected ip blocks.
> 
> Doing that only for affected IP blocks may miss integration differences.
> Of course, you can always resort to soc_device_match() to handle those...
> 
> Gr{oetje,eeting}s,
> 
>                          Geert
> 

It would be a great idea indeed if there was not this clock registration 
too soon for initcalls.

I am currently running out of ideas to propose a better solution than 
this V1. Is anyone has any recommendation to handle that? I would really 
appreciate :)

Thank you in advance!
Best regards,
Mylène
Geert Uytterhoeven March 26, 2020, 3:31 p.m. UTC | #10
Hi Mylene,

On Thu, Mar 26, 2020 at 2:50 PM Mylene Josserand
<mylene.josserand@collabora.com> wrote:
> On 3/6/20 11:45 AM, Geert Uytterhoeven wrote:
> > On Wed, Mar 4, 2020 at 12:00 PM Heiko Stübner <heiko@sntech.de> wrote:
> >> Am Montag, 2. März 2020, 16:57:02 CET schrieb Mylène Josserand:
> >>> Determine which revision of rk3288 by checking the HDMI version.
> >>> According to the Rockchip BSP kernel, on rk3288w, the HDMI
> >>> revision equals 0x1A which is not the case for the rk3288 [1].
> >>>
> >>> As these SOC have some differences, the new function
> >>> 'soc_is_rk3288w' will help us to know on which revision
> >>> we are.
> >>
> >> what happened to just having a different compatible in the dts?
> >> Aka doing a
> >>
> >> rk3288w.dtsi with
> >>
> >> #include "rk3288.dtsi"
> >>
> >> &cru {
> >>          compatible = "rockchip,rk3288w-cru";
> >> }
> >>
> >> I somehow don't expect boards to just switch between soc variants
> >> on the fly.
> >>
> >> Also, doing things in mach-rockchip is not very future-proof:
> >>
> >> (1) having random soc-specific APIs spanning the kernel feels wrong,
> >>      especially as at some point it might not be contained to our own special
> >>      drivers like the cru. I cannot really see people being enthusiastic if
> >>      something like this would be needed in say the core Analogix-DP bridge ;-)
> >
> > Indeed.  You're better of registering an soc_device_attribute using
> > soc_device_register(), after which any driver can use soc_device_match()
> > to differentiate based on the SoC revision.
>
> Thank you for this suggestion. The issue is that clocks are registered
> at an early stage of the boot so using initcalls is too late for the
> clock differentiation :(

IC, rk388 is still using CLK_OF_DECLARE().
What about converting it to a platform driver, registered from e.g.
subsys_initcall()?
If you need some clocks early (e.g. for timers), you can do split
registration, with the early part still using CLK_OF_DECLARE().
That should work, assumed the timer clocks don't need differentiation.

Gr{oetje,eeting}s,

                        Geert
Mylene Josserand March 27, 2020, 6:20 a.m. UTC | #11
Hi Geert,

On 3/26/20 4:31 PM, Geert Uytterhoeven wrote:
> Hi Mylene,
> 
> On Thu, Mar 26, 2020 at 2:50 PM Mylene Josserand
> <mylene.josserand@collabora.com> wrote:
>> On 3/6/20 11:45 AM, Geert Uytterhoeven wrote:
>>> On Wed, Mar 4, 2020 at 12:00 PM Heiko Stübner <heiko@sntech.de> wrote:
>>>> Am Montag, 2. März 2020, 16:57:02 CET schrieb Mylène Josserand:
>>>>> Determine which revision of rk3288 by checking the HDMI version.
>>>>> According to the Rockchip BSP kernel, on rk3288w, the HDMI
>>>>> revision equals 0x1A which is not the case for the rk3288 [1].
>>>>>
>>>>> As these SOC have some differences, the new function
>>>>> 'soc_is_rk3288w' will help us to know on which revision
>>>>> we are.
>>>>
>>>> what happened to just having a different compatible in the dts?
>>>> Aka doing a
>>>>
>>>> rk3288w.dtsi with
>>>>
>>>> #include "rk3288.dtsi"
>>>>
>>>> &cru {
>>>>           compatible = "rockchip,rk3288w-cru";
>>>> }
>>>>
>>>> I somehow don't expect boards to just switch between soc variants
>>>> on the fly.
>>>>
>>>> Also, doing things in mach-rockchip is not very future-proof:
>>>>
>>>> (1) having random soc-specific APIs spanning the kernel feels wrong,
>>>>       especially as at some point it might not be contained to our own special
>>>>       drivers like the cru. I cannot really see people being enthusiastic if
>>>>       something like this would be needed in say the core Analogix-DP bridge ;-)
>>>
>>> Indeed.  You're better of registering an soc_device_attribute using
>>> soc_device_register(), after which any driver can use soc_device_match()
>>> to differentiate based on the SoC revision.
>>
>> Thank you for this suggestion. The issue is that clocks are registered
>> at an early stage of the boot so using initcalls is too late for the
>> clock differentiation :(
> 
> IC, rk388 is still using CLK_OF_DECLARE().
> What about converting it to a platform driver, registered from e.g.
> subsys_initcall()?
> If you need some clocks early (e.g. for timers), you can do split
> registration, with the early part still using CLK_OF_DECLARE().
> That should work, assumed the timer clocks don't need differentiation.
> 
> Gr{oetje,eeting}s,
> 
>                          Geert
> 

oh, nice, thanks for the help!
I will try that and send a new version if it is working fine.

Best regards,
Mylène
diff mbox series

Patch

diff --git a/arch/arm/mach-rockchip/rockchip.c b/arch/arm/mach-rockchip/rockchip.c
index f9797a2b5d0d..b907ba390093 100644
--- a/arch/arm/mach-rockchip/rockchip.c
+++ b/arch/arm/mach-rockchip/rockchip.c
@@ -9,12 +9,14 @@ 
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/io.h>
+#include <linux/of_address.h>
 #include <linux/of_platform.h>
 #include <linux/irqchip.h>
 #include <linux/clk-provider.h>
 #include <linux/clocksource.h>
 #include <linux/mfd/syscon.h>
 #include <linux/regmap.h>
+#include <soc/rockchip/revision.h>
 #include <asm/mach/arch.h>
 #include <asm/mach/map.h>
 #include <asm/hardware/cache-l2x0.h>
@@ -22,6 +24,49 @@ 
 #include "pm.h"
 
 #define RK3288_TIMER6_7_PHYS 0xff810000
+#define RK3288_HDMI_REV_REG	0x04
+#define RK3288W_HDMI_REV	0x1A
+
+static const struct of_device_id rk3288_dt_hdmi_match[] __initconst = {
+	{ .compatible = "rockchip,rk3288-dw-hdmi" },
+	{ }
+};
+
+int rk3288_get_revision(void)
+{
+	static int revision = RK3288_SOC_REV_UNKNOWN;
+	struct device_node *dn;
+	void __iomem *hdmi_base;
+
+	if (revision != RK3288_SOC_REV_UNKNOWN)
+		return revision;
+
+	dn = of_find_matching_node(NULL, rk3288_dt_hdmi_match);
+	if (!dn) {
+		pr_err("%s: Couldn't find HDMI node\n", __func__);
+		return -EINVAL;
+	}
+
+	hdmi_base = of_iomap(dn, 0);
+	of_node_put(dn);
+
+	if (!hdmi_base) {
+		pr_err("%s: Couldn't map %pOF regs\n", __func__,
+		       hdmi_base);
+		return -ENXIO;
+	}
+
+	if (readl_relaxed(hdmi_base + RK3288_HDMI_REV_REG) ==
+	    RK3288W_HDMI_REV)
+		revision = RK3288_SOC_REV_RK3288W;
+	else
+		revision = RK3288_SOC_REV_RK3288;
+
+	iounmap(hdmi_base);
+
+	return revision;
+}
+EXPORT_SYMBOL(rk3288_get_revision);
 
 static void __init rockchip_timer_init(void)
 {
diff --git a/include/soc/rockchip/revision.h b/include/soc/rockchip/revision.h
new file mode 100644
index 000000000000..226419c60af0
--- /dev/null
+++ b/include/soc/rockchip/revision.h
@@ -0,0 +1,22 @@ 
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright 2020 Collabora
+ */
+
+#ifndef __SOC_ROCKCHIP_REVISION_H__
+#define __SOC_ROCKCHIP_REVISION_H__
+
+enum rk3288_soc_revision {
+	RK3288_SOC_REV_UNKNOWN,
+	RK3288_SOC_REV_RK3288,
+	RK3288_SOC_REV_RK3288W,
+};
+
+int rk3288_get_revision(void);
+
+static inline bool soc_is_rk3288w(void)
+{
+	return rk3288_get_revision() == RK3288_SOC_REV_RK3288W;
+}
+
+#endif /* __SOC_ROCKCHIP_REVISION_H__ */