* [PATCH] ARM: dts: at91: sama5d2: use the divided clock for SMC
@ 2018-11-20 16:57 Romain Izard
2018-11-20 17:16 ` Alexandre Belloni
0 siblings, 1 reply; 5+ messages in thread
From: Romain Izard @ 2018-11-20 16:57 UTC (permalink / raw)
To: Nicolas Ferre, Alexandre Belloni, Tudor Ambarus
Cc: Rob Herring, Mark Rutland, linux-arm-kernel, devicetree,
linux-kernel, Romain Izard
The SAMA5D2 is different from SAMA5D3 and SAMA5D4, as there are two
different clocks for the peripherals in the SoC. The Static Memory
controller is connected to the divided master clock.
Unfortunately, the device tree does not correctly show this and uses the
master clock directly. This clock is then used by the code for the NAND
controller to calculate the timings for the controller, and we end up with
slow NAND Flash access.
Fix the device tree, and the performance of Flash access is improved.
Signed-off-by: Romain Izard <romain.izard.pro@gmail.com>
---
arch/arm/boot/dts/sama5d2.dtsi | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/arm/boot/dts/sama5d2.dtsi b/arch/arm/boot/dts/sama5d2.dtsi
index 61f68e5c48e9..b405992eb601 100644
--- a/arch/arm/boot/dts/sama5d2.dtsi
+++ b/arch/arm/boot/dts/sama5d2.dtsi
@@ -308,7 +308,7 @@
0x1 0x0 0x60000000 0x10000000
0x2 0x0 0x70000000 0x10000000
0x3 0x0 0x80000000 0x10000000>;
- clocks = <&mck>;
+ clocks = <&h32ck>;
status = "disabled";
nand_controller: nand-controller {
--
2.17.1
^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH] ARM: dts: at91: sama5d2: use the divided clock for SMC
2018-11-20 16:57 [PATCH] ARM: dts: at91: sama5d2: use the divided clock for SMC Romain Izard
@ 2018-11-20 17:16 ` Alexandre Belloni
2018-11-20 18:01 ` Romain Izard
0 siblings, 1 reply; 5+ messages in thread
From: Alexandre Belloni @ 2018-11-20 17:16 UTC (permalink / raw)
To: Romain Izard
Cc: Nicolas Ferre, Tudor Ambarus, Rob Herring, Mark Rutland,
linux-arm-kernel, devicetree, linux-kernel
Hello Romain,
On 20/11/2018 17:57:37+0100, Romain Izard wrote:
> The SAMA5D2 is different from SAMA5D3 and SAMA5D4, as there are two
> different clocks for the peripherals in the SoC. The Static Memory
> controller is connected to the divided master clock.
>
> Unfortunately, the device tree does not correctly show this and uses the
> master clock directly. This clock is then used by the code for the NAND
> controller to calculate the timings for the controller, and we end up with
> slow NAND Flash access.
>
> Fix the device tree, and the performance of Flash access is improved.
>
> Signed-off-by: Romain Izard <romain.izard.pro@gmail.com>
> ---
> arch/arm/boot/dts/sama5d2.dtsi | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/arm/boot/dts/sama5d2.dtsi b/arch/arm/boot/dts/sama5d2.dtsi
> index 61f68e5c48e9..b405992eb601 100644
> --- a/arch/arm/boot/dts/sama5d2.dtsi
> +++ b/arch/arm/boot/dts/sama5d2.dtsi
> @@ -308,7 +308,7 @@
> 0x1 0x0 0x60000000 0x10000000
> 0x2 0x0 0x70000000 0x10000000
> 0x3 0x0 0x80000000 0x10000000>;
> - clocks = <&mck>;
> + clocks = <&h32ck>;
You will have to rebase on top of at91-dt. And if I'm not mistaken, this
line should be:
+ clocks = <&pmc PMC_TYPE_CORE PMC_MCK2>;
> status = "disabled";
>
> nand_controller: nand-controller {
> --
> 2.17.1
>
--
Alexandre Belloni, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] ARM: dts: at91: sama5d2: use the divided clock for SMC
2018-11-20 17:16 ` Alexandre Belloni
@ 2018-11-20 18:01 ` Romain Izard
2018-11-20 20:40 ` Alexandre Belloni
0 siblings, 1 reply; 5+ messages in thread
From: Romain Izard @ 2018-11-20 18:01 UTC (permalink / raw)
To: Alexandre Belloni
Cc: Nicolas Ferre, Tudor Ambarus, Rob Herring, mark.rutland,
linux-arm-kernel, devicetree, LKML
Le mar. 20 nov. 2018 à 18:16, Alexandre Belloni
<alexandre.belloni@bootlin.com> a écrit :
>
> Hello Romain,
>
> On 20/11/2018 17:57:37+0100, Romain Izard wrote:
> > The SAMA5D2 is different from SAMA5D3 and SAMA5D4, as there are two
> > different clocks for the peripherals in the SoC. The Static Memory
> > controller is connected to the divided master clock.
> >
> > Unfortunately, the device tree does not correctly show this and uses the
> > master clock directly. This clock is then used by the code for the NAND
> > controller to calculate the timings for the controller, and we end up with
> > slow NAND Flash access.
> >
> > Fix the device tree, and the performance of Flash access is improved.
> >
> > Signed-off-by: Romain Izard <romain.izard.pro@gmail.com>
> > ---
> > arch/arm/boot/dts/sama5d2.dtsi | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/arch/arm/boot/dts/sama5d2.dtsi b/arch/arm/boot/dts/sama5d2.dtsi
> > index 61f68e5c48e9..b405992eb601 100644
> > --- a/arch/arm/boot/dts/sama5d2.dtsi
> > +++ b/arch/arm/boot/dts/sama5d2.dtsi
> > @@ -308,7 +308,7 @@
> > 0x1 0x0 0x60000000 0x10000000
> > 0x2 0x0 0x70000000 0x10000000
> > 0x3 0x0 0x80000000 0x10000000>;
> > - clocks = <&mck>;
> > + clocks = <&h32ck>;
>
> You will have to rebase on top of at91-dt. And if I'm not mistaken, this
> line should be:
>
> + clocks = <&pmc PMC_TYPE_CORE PMC_MCK2>;
>
> > status = "disabled";
> >
> > nand_controller: nand-controller {
I guess you're right but this will only reach mainline in 4.21. I get slow
flash access with 4.19 as well...
After a second look, it looks like the SAMA5D4 is affected too.
Best regards,
--
Romain Izard
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] ARM: dts: at91: sama5d2: use the divided clock for SMC
2018-11-20 18:01 ` Romain Izard
@ 2018-11-20 20:40 ` Alexandre Belloni
2018-11-21 11:00 ` Alexandre Belloni
0 siblings, 1 reply; 5+ messages in thread
From: Alexandre Belloni @ 2018-11-20 20:40 UTC (permalink / raw)
To: Romain Izard
Cc: Nicolas Ferre, Tudor Ambarus, Rob Herring, mark.rutland,
linux-arm-kernel, devicetree, LKML
On 20/11/2018 19:01:32+0100, Romain Izard wrote:
> Le mar. 20 nov. 2018 à 18:16, Alexandre Belloni
> <alexandre.belloni@bootlin.com> a écrit :
> >
> > Hello Romain,
> >
> > On 20/11/2018 17:57:37+0100, Romain Izard wrote:
> > > The SAMA5D2 is different from SAMA5D3 and SAMA5D4, as there are two
> > > different clocks for the peripherals in the SoC. The Static Memory
> > > controller is connected to the divided master clock.
> > >
> > > Unfortunately, the device tree does not correctly show this and uses the
> > > master clock directly. This clock is then used by the code for the NAND
> > > controller to calculate the timings for the controller, and we end up with
> > > slow NAND Flash access.
> > >
> > > Fix the device tree, and the performance of Flash access is improved.
> > >
> > > Signed-off-by: Romain Izard <romain.izard.pro@gmail.com>
> > > ---
> > > arch/arm/boot/dts/sama5d2.dtsi | 2 +-
> > > 1 file changed, 1 insertion(+), 1 deletion(-)
> > >
> > > diff --git a/arch/arm/boot/dts/sama5d2.dtsi b/arch/arm/boot/dts/sama5d2.dtsi
> > > index 61f68e5c48e9..b405992eb601 100644
> > > --- a/arch/arm/boot/dts/sama5d2.dtsi
> > > +++ b/arch/arm/boot/dts/sama5d2.dtsi
> > > @@ -308,7 +308,7 @@
> > > 0x1 0x0 0x60000000 0x10000000
> > > 0x2 0x0 0x70000000 0x10000000
> > > 0x3 0x0 0x80000000 0x10000000>;
> > > - clocks = <&mck>;
> > > + clocks = <&h32ck>;
> >
> > You will have to rebase on top of at91-dt. And if I'm not mistaken, this
> > line should be:
> >
> > + clocks = <&pmc PMC_TYPE_CORE PMC_MCK2>;
> >
> > > status = "disabled";
> > >
> > > nand_controller: nand-controller {
>
> I guess you're right but this will only reach mainline in 4.21. I get slow
> flash access with 4.19 as well...
>
Ok, this is super annoying, I'll try to get that as fixes on v4.20 and
I'll rebase at91-dt on top of that...
--
Alexandre Belloni, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] ARM: dts: at91: sama5d2: use the divided clock for SMC
2018-11-20 20:40 ` Alexandre Belloni
@ 2018-11-21 11:00 ` Alexandre Belloni
0 siblings, 0 replies; 5+ messages in thread
From: Alexandre Belloni @ 2018-11-21 11:00 UTC (permalink / raw)
To: Romain Izard
Cc: Nicolas Ferre, Tudor Ambarus, Rob Herring, mark.rutland,
linux-arm-kernel, devicetree, LKML
On 20/11/2018 21:40:49+0100, Alexandre Belloni wrote:
> On 20/11/2018 19:01:32+0100, Romain Izard wrote:
> > Le mar. 20 nov. 2018 à 18:16, Alexandre Belloni
> > <alexandre.belloni@bootlin.com> a écrit :
> > >
> > > Hello Romain,
> > >
> > > On 20/11/2018 17:57:37+0100, Romain Izard wrote:
> > > > The SAMA5D2 is different from SAMA5D3 and SAMA5D4, as there are two
> > > > different clocks for the peripherals in the SoC. The Static Memory
> > > > controller is connected to the divided master clock.
> > > >
> > > > Unfortunately, the device tree does not correctly show this and uses the
> > > > master clock directly. This clock is then used by the code for the NAND
> > > > controller to calculate the timings for the controller, and we end up with
> > > > slow NAND Flash access.
> > > >
> > > > Fix the device tree, and the performance of Flash access is improved.
> > > >
> > > > Signed-off-by: Romain Izard <romain.izard.pro@gmail.com>
> > > > ---
> > > > arch/arm/boot/dts/sama5d2.dtsi | 2 +-
> > > > 1 file changed, 1 insertion(+), 1 deletion(-)
> > > >
> > > > diff --git a/arch/arm/boot/dts/sama5d2.dtsi b/arch/arm/boot/dts/sama5d2.dtsi
> > > > index 61f68e5c48e9..b405992eb601 100644
> > > > --- a/arch/arm/boot/dts/sama5d2.dtsi
> > > > +++ b/arch/arm/boot/dts/sama5d2.dtsi
> > > > @@ -308,7 +308,7 @@
> > > > 0x1 0x0 0x60000000 0x10000000
> > > > 0x2 0x0 0x70000000 0x10000000
> > > > 0x3 0x0 0x80000000 0x10000000>;
> > > > - clocks = <&mck>;
> > > > + clocks = <&h32ck>;
> > >
> > > You will have to rebase on top of at91-dt. And if I'm not mistaken, this
> > > line should be:
> > >
> > > + clocks = <&pmc PMC_TYPE_CORE PMC_MCK2>;
> > >
> > > > status = "disabled";
> > > >
> > > > nand_controller: nand-controller {
> >
> > I guess you're right but this will only reach mainline in 4.21. I get slow
> > flash access with 4.19 as well...
> >
>
> Ok, this is super annoying, I'll try to get that as fixes on v4.20 and
> I'll rebase at91-dt on top of that...
>
So, I did that just now.
--
Alexandre Belloni, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2018-11-21 11:01 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-11-20 16:57 [PATCH] ARM: dts: at91: sama5d2: use the divided clock for SMC Romain Izard
2018-11-20 17:16 ` Alexandre Belloni
2018-11-20 18:01 ` Romain Izard
2018-11-20 20:40 ` Alexandre Belloni
2018-11-21 11:00 ` Alexandre Belloni
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).