[PATCH] ARM: shmobile: r8a7779: Add L2 cache-controller node

[PATCH] ARM: shmobile: r8a7779: Add L2 cache-controller node

[Simon Horman]

Add the missing L2 cache-controller node, and link the CPU nodes to it.

The L2 cache is an ARM L2C-310 (r3p2), of size 1 MB (64 KiB x 16 ways).

Based on work for the r8a7740 by Geert Uytterhoeven.

Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

---

* About the r8a7778 (M1A)

  My reading of the documentation is that although a pl310 L2 cache
  controller is present it is not available for use as there is no L2
  cache memory present. For this reason I do not intend to follow up
  with a similar patch for the r8a7798.

* Lightly tested against renesas-devel-20151124-v4.4-rc2
---
 arch/arm/boot/dts/r8a7779.dtsi | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/arch/arm/boot/dts/r8a7779.dtsi b/arch/arm/boot/dts/r8a7779.dtsi
index 6afa909865b5..f27fa2db16ee 100644
--- a/arch/arm/boot/dts/r8a7779.dtsi
+++ b/arch/arm/boot/dts/r8a7779.dtsi
@@ -28,24 +28,28 @@
 			compatible = "arm,cortex-a9";
 			reg = <0>;
 			clock-frequency = <1000000000>;
+			next-level-cache = <&L2>;
 		};
 		cpu@1 {
 			device_type = "cpu";
 			compatible = "arm,cortex-a9";
 			reg = <1>;
 			clock-frequency = <1000000000>;
+			next-level-cache = <&L2>;
 		};
 		cpu@2 {
 			device_type = "cpu";
 			compatible = "arm,cortex-a9";
 			reg = <2>;
 			clock-frequency = <1000000000>;
+			next-level-cache = <&L2>;
 		};
 		cpu@3 {
 			device_type = "cpu";
 			compatible = "arm,cortex-a9";
 			reg = <3>;
 			clock-frequency = <1000000000>;
+			next-level-cache = <&L2>;
 		};
 	};
 
@@ -63,6 +67,17 @@
 		      <0xf0000100 0x100>;
 	};
 
+	L2: cache-controller {
+		compatible = "arm,pl310-cache";
+		reg = <0xf0100000 0x1000>;
+		interrupts = <0 122 IRQ_TYPE_LEVEL_HIGH>;
+		arm,data-latency = <3 3 3>;
+		arm,tag-latency = <2 2 2>;
+		arm,shared-override;
+		cache-unified;
+		cache-level = <2>;
+	};
+
 	timer@f0000600 {
 		compatible = "arm,cortex-a9-twd-timer";
 		reg = <0xf0000600 0x20>;
-- 
2.1.4

[PATCH] ARM: shmobile: r8a7779: Add L2 cache-controller node

[Simon Horman]

Add the missing L2 cache-controller node, and link the CPU nodes to it.

The L2 cache is an ARM L2C-310 (r3p2), of size 1 MB (64 KiB x 16 ways).

Based on work for the r8a7740 by Geert Uytterhoeven.

Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

---

* About the r8a7778 (M1A)

  My reading of the documentation is that although a pl310 L2 cache
  controller is present it is not available for use as there is no L2
  cache memory present. For this reason I do not intend to follow up
  with a similar patch for the r8a7798.

* Lightly tested against renesas-devel-20151124-v4.4-rc2
---
 arch/arm/boot/dts/r8a7779.dtsi | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/arch/arm/boot/dts/r8a7779.dtsi b/arch/arm/boot/dts/r8a7779.dtsi
index 6afa909865b5..f27fa2db16ee 100644
--- a/arch/arm/boot/dts/r8a7779.dtsi
+++ b/arch/arm/boot/dts/r8a7779.dtsi
@@ -28,24 +28,28 @@
 			compatible = "arm,cortex-a9";
 			reg = <0>;
 			clock-frequency = <1000000000>;
+			next-level-cache = <&L2>;
 		};
 		cpu at 1 {
 			device_type = "cpu";
 			compatible = "arm,cortex-a9";
 			reg = <1>;
 			clock-frequency = <1000000000>;
+			next-level-cache = <&L2>;
 		};
 		cpu at 2 {
 			device_type = "cpu";
 			compatible = "arm,cortex-a9";
 			reg = <2>;
 			clock-frequency = <1000000000>;
+			next-level-cache = <&L2>;
 		};
 		cpu at 3 {
 			device_type = "cpu";
 			compatible = "arm,cortex-a9";
 			reg = <3>;
 			clock-frequency = <1000000000>;
+			next-level-cache = <&L2>;
 		};
 	};
 
@@ -63,6 +67,17 @@
 		      <0xf0000100 0x100>;
 	};
 
+	L2: cache-controller {
+		compatible = "arm,pl310-cache";
+		reg = <0xf0100000 0x1000>;
+		interrupts = <0 122 IRQ_TYPE_LEVEL_HIGH>;
+		arm,data-latency = <3 3 3>;
+		arm,tag-latency = <2 2 2>;
+		arm,shared-override;
+		cache-unified;
+		cache-level = <2>;
+	};
+
 	timer at f0000600 {
 		compatible = "arm,cortex-a9-twd-timer";
 		reg = <0xf0000600 0x20>;
-- 
2.1.4

Re: [PATCH] ARM: shmobile: r8a7779: Add L2 cache-controller node

[Geert Uytterhoeven]

Hi Simon,

On Wed, Nov 25, 2015 at 2:58 AM, Simon Horman
<horms+renesas@verge.net.au> wrote:
> Add the missing L2 cache-controller node, and link the CPU nodes to it.
>
> The L2 cache is an ARM L2C-310 (r3p2), of size 1 MB (64 KiB x 16 ways).
>
> Based on work for the r8a7740 by Geert Uytterhoeven.
>
> Cc: Geert Uytterhoeven <geert+renesas@glider.be>
> Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

Thanks for your patch!

> ---
>  arch/arm/boot/dts/r8a7779.dtsi | 15 +++++++++++++++
>  1 file changed, 15 insertions(+)
>
> diff --git a/arch/arm/boot/dts/r8a7779.dtsi b/arch/arm/boot/dts/r8a7779.dtsi
> index 6afa909865b5..f27fa2db16ee 100644
> --- a/arch/arm/boot/dts/r8a7779.dtsi
> +++ b/arch/arm/boot/dts/r8a7779.dtsi

> @@ -63,6 +67,17 @@
>                       <0xf0000100 0x100>;
>         };
>
> +       L2: cache-controller {
> +               compatible = "arm,pl310-cache";
> +               reg = <0xf0100000 0x1000>;
> +               interrupts = <0 122 IRQ_TYPE_LEVEL_HIGH>;

40?

Comparing to other devices, you have to subtract 32 from 0x5a, not
add 32?

> +               arm,data-latency = <3 3 3>;
> +               arm,tag-latency = <2 2 2>;

Table 9.5 says 2 resp. 1 instead of 3 resp. 2?

However:

"The TAG and data RAM latency can be set in the reg1_tag_ram_control and
 reg1_data_ram_control registers. However, since values to be set are
 hardware-dependent, the default values should not be modified."

Perhaps we should just omit these values?

> +               arm,shared-override;
> +               cache-unified;
> +               cache-level = <2>;
> +       };
> +

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

[PATCH] ARM: shmobile: r8a7779: Add L2 cache-controller node

[Geert Uytterhoeven]

Hi Simon,

On Wed, Nov 25, 2015 at 2:58 AM, Simon Horman
<horms+renesas@verge.net.au> wrote:
> Add the missing L2 cache-controller node, and link the CPU nodes to it.
>
> The L2 cache is an ARM L2C-310 (r3p2), of size 1 MB (64 KiB x 16 ways).
>
> Based on work for the r8a7740 by Geert Uytterhoeven.
>
> Cc: Geert Uytterhoeven <geert+renesas@glider.be>
> Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

Thanks for your patch!

> ---
>  arch/arm/boot/dts/r8a7779.dtsi | 15 +++++++++++++++
>  1 file changed, 15 insertions(+)
>
> diff --git a/arch/arm/boot/dts/r8a7779.dtsi b/arch/arm/boot/dts/r8a7779.dtsi
> index 6afa909865b5..f27fa2db16ee 100644
> --- a/arch/arm/boot/dts/r8a7779.dtsi
> +++ b/arch/arm/boot/dts/r8a7779.dtsi

> @@ -63,6 +67,17 @@
>                       <0xf0000100 0x100>;
>         };
>
> +       L2: cache-controller {
> +               compatible = "arm,pl310-cache";
> +               reg = <0xf0100000 0x1000>;
> +               interrupts = <0 122 IRQ_TYPE_LEVEL_HIGH>;

40?

Comparing to other devices, you have to subtract 32 from 0x5a, not
add 32?

> +               arm,data-latency = <3 3 3>;
> +               arm,tag-latency = <2 2 2>;

Table 9.5 says 2 resp. 1 instead of 3 resp. 2?

However:

"The TAG and data RAM latency can be set in the reg1_tag_ram_control and
 reg1_data_ram_control registers. However, since values to be set are
 hardware-dependent, the default values should not be modified."

Perhaps we should just omit these values?

> +               arm,shared-override;
> +               cache-unified;
> +               cache-level = <2>;
> +       };
> +

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH] ARM: shmobile: r8a7779: Add L2 cache-controller node

[Simon Horman]

On Wed, Nov 25, 2015 at 09:41:42AM +0100, Geert Uytterhoeven wrote:
> Hi Simon,
> 
> On Wed, Nov 25, 2015 at 2:58 AM, Simon Horman
> <horms+renesas@verge.net.au> wrote:
> > Add the missing L2 cache-controller node, and link the CPU nodes to it.
> >
> > The L2 cache is an ARM L2C-310 (r3p2), of size 1 MB (64 KiB x 16 ways).
> >
> > Based on work for the r8a7740 by Geert Uytterhoeven.
> >
> > Cc: Geert Uytterhoeven <geert+renesas@glider.be>
> > Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
> 
> Thanks for your patch!
> 
> > ---
> >  arch/arm/boot/dts/r8a7779.dtsi | 15 +++++++++++++++
> >  1 file changed, 15 insertions(+)
> >
> > diff --git a/arch/arm/boot/dts/r8a7779.dtsi b/arch/arm/boot/dts/r8a7779.dtsi
> > index 6afa909865b5..f27fa2db16ee 100644
> > --- a/arch/arm/boot/dts/r8a7779.dtsi
> > +++ b/arch/arm/boot/dts/r8a7779.dtsi
> 
> > @@ -63,6 +67,17 @@
> >                       <0xf0000100 0x100>;
> >         };
> >
> > +       L2: cache-controller {
> > +               compatible = "arm,pl310-cache";
> > +               reg = <0xf0100000 0x1000>;
> > +               interrupts = <0 122 IRQ_TYPE_LEVEL_HIGH>;
> 
> 40?
> 
> Comparing to other devices, you have to subtract 32 from 0x5a, not
> add 32?

Thanks for pointing that out. I will update this to 0x5a - 32 = 58

> > +               arm,data-latency = <3 3 3>;
> > +               arm,tag-latency = <2 2 2>;
> 
> Table 9.5 says 2 resp. 1 instead of 3 resp. 2?

Thanks.

> However:
> 
> "The TAG and data RAM latency can be set in the reg1_tag_ram_control and
>  reg1_data_ram_control registers. However, since values to be set are
>  hardware-dependent, the default values should not be modified."
> 
> Perhaps we should just omit these values?

I see also see remarks regarding the values not being configurable
for the r8a7740 (section 2.7.1) and sh73a0 (section 6.10.1) so perhaps we
should remove the values from the dts files of those SoCs too?

[PATCH] ARM: shmobile: r8a7779: Add L2 cache-controller node

[Simon Horman]

On Wed, Nov 25, 2015 at 09:41:42AM +0100, Geert Uytterhoeven wrote:
> Hi Simon,
> 
> On Wed, Nov 25, 2015 at 2:58 AM, Simon Horman
> <horms+renesas@verge.net.au> wrote:
> > Add the missing L2 cache-controller node, and link the CPU nodes to it.
> >
> > The L2 cache is an ARM L2C-310 (r3p2), of size 1 MB (64 KiB x 16 ways).
> >
> > Based on work for the r8a7740 by Geert Uytterhoeven.
> >
> > Cc: Geert Uytterhoeven <geert+renesas@glider.be>
> > Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
> 
> Thanks for your patch!
> 
> > ---
> >  arch/arm/boot/dts/r8a7779.dtsi | 15 +++++++++++++++
> >  1 file changed, 15 insertions(+)
> >
> > diff --git a/arch/arm/boot/dts/r8a7779.dtsi b/arch/arm/boot/dts/r8a7779.dtsi
> > index 6afa909865b5..f27fa2db16ee 100644
> > --- a/arch/arm/boot/dts/r8a7779.dtsi
> > +++ b/arch/arm/boot/dts/r8a7779.dtsi
> 
> > @@ -63,6 +67,17 @@
> >                       <0xf0000100 0x100>;
> >         };
> >
> > +       L2: cache-controller {
> > +               compatible = "arm,pl310-cache";
> > +               reg = <0xf0100000 0x1000>;
> > +               interrupts = <0 122 IRQ_TYPE_LEVEL_HIGH>;
> 
> 40?
> 
> Comparing to other devices, you have to subtract 32 from 0x5a, not
> add 32?

Thanks for pointing that out. I will update this to 0x5a - 32 = 58

> > +               arm,data-latency = <3 3 3>;
> > +               arm,tag-latency = <2 2 2>;
> 
> Table 9.5 says 2 resp. 1 instead of 3 resp. 2?

Thanks.

> However:
> 
> "The TAG and data RAM latency can be set in the reg1_tag_ram_control and
>  reg1_data_ram_control registers. However, since values to be set are
>  hardware-dependent, the default values should not be modified."
> 
> Perhaps we should just omit these values?

I see also see remarks regarding the values not being configurable
for the r8a7740 (section 2.7.1) and sh73a0 (section 6.10.1) so perhaps we
should remove the values from the dts files of those SoCs too?