* Re: [PATCH 4/8] ARM: shmobile: lager: Add dummy PCIe bus clock
2014-05-28 7:23 [PATCH 4/8] ARM: shmobile: lager: Add dummy PCIe bus clock Phil Edworthy
@ 2014-05-28 12:44 ` Sergei Shtylyov
2014-05-28 15:04 ` Phil Edworthy
` (3 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: Sergei Shtylyov @ 2014-05-28 12:44 UTC (permalink / raw)
To: linux-sh
Hello.
On 05/28/2014 11:23 AM, Phil Edworthy wrote:
> Since the CPU's dtsi refers to pcie_bus_clock, we need an entry in
> the board's dts, even if we aren't using PCIe.
> Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com>
> ---
> arch/arm/boot/dts/r8a7790-lager.dts | 10 ++++++++++
> 1 file changed, 10 insertions(+)
> diff --git a/arch/arm/boot/dts/r8a7790-lager.dts b/arch/arm/boot/dts/r8a7790-lager.dts
> index 9becef7..6d4fe97 100644
> --- a/arch/arm/boot/dts/r8a7790-lager.dts
> +++ b/arch/arm/boot/dts/r8a7790-lager.dts
> @@ -144,6 +144,16 @@
> states = <3300000 1
> 1800000 0>;
> };
> +
> + clocks {
> + /* External PCIe bus clock - not used */
> + pcie_bus_clk: pcie_bus_clk {
> + compatible = "fixed-clock";
> + #clock-cells = <0>;
> + clock-frequency = <0>;
When this value gets filled in?
WBR, Sergei
^ permalink raw reply [flat|nested] 6+ messages in thread* RE: [PATCH 4/8] ARM: shmobile: lager: Add dummy PCIe bus clock
2014-05-28 7:23 [PATCH 4/8] ARM: shmobile: lager: Add dummy PCIe bus clock Phil Edworthy
2014-05-28 12:44 ` Sergei Shtylyov
@ 2014-05-28 15:04 ` Phil Edworthy
2014-05-28 17:40 ` Sergei Shtylyov
` (2 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: Phil Edworthy @ 2014-05-28 15:04 UTC (permalink / raw)
To: linux-sh
Hi Sergei,
On 28 May 2014 13:44, Sergei wrote:
> On 05/28/2014 11:23 AM, Phil Edworthy wrote:
>
> > Since the CPU's dtsi refers to pcie_bus_clock, we need an entry in
> > the board's dts, even if we aren't using PCIe.
>
> > Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com>
> > ---
> > arch/arm/boot/dts/r8a7790-lager.dts | 10 ++++++++++
> > 1 file changed, 10 insertions(+)
>
> > diff --git a/arch/arm/boot/dts/r8a7790-lager.dts
> b/arch/arm/boot/dts/r8a7790-lager.dts
> > index 9becef7..6d4fe97 100644
> > --- a/arch/arm/boot/dts/r8a7790-lager.dts
> > +++ b/arch/arm/boot/dts/r8a7790-lager.dts
> > @@ -144,6 +144,16 @@
> > states = <3300000 1
> > 1800000 0>;
> > };
> > +
> > + clocks {
> > + /* External PCIe bus clock - not used */
> > + pcie_bus_clk: pcie_bus_clk {
> > + compatible = "fixed-clock";
> > + #clock-cells = <0>;
> > + clock-frequency = <0>;
>
> When this value gets filled in?
It doesn't. On the Lager board, there is no PCIe support.
It's needed as pcie_bus_clk is referenced from r8a7790.dtsi and without it
you'll get build failures.
Cheers
Phil
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH 4/8] ARM: shmobile: lager: Add dummy PCIe bus clock
2014-05-28 7:23 [PATCH 4/8] ARM: shmobile: lager: Add dummy PCIe bus clock Phil Edworthy
2014-05-28 12:44 ` Sergei Shtylyov
2014-05-28 15:04 ` Phil Edworthy
@ 2014-05-28 17:40 ` Sergei Shtylyov
2014-05-29 14:46 ` Phil Edworthy
2014-06-10 8:06 ` Phil Edworthy
4 siblings, 0 replies; 6+ messages in thread
From: Sergei Shtylyov @ 2014-05-28 17:40 UTC (permalink / raw)
To: linux-sh
On 05/28/2014 07:04 PM, Phil Edworthy wrote:
>>> Since the CPU's dtsi refers to pcie_bus_clock, we need an entry in
>>> the board's dts, even if we aren't using PCIe.
>>> Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com>
>>> ---
>>> arch/arm/boot/dts/r8a7790-lager.dts | 10 ++++++++++
>>> 1 file changed, 10 insertions(+)
>>> diff --git a/arch/arm/boot/dts/r8a7790-lager.dts
>> b/arch/arm/boot/dts/r8a7790-lager.dts
>>> index 9becef7..6d4fe97 100644
>>> --- a/arch/arm/boot/dts/r8a7790-lager.dts
>>> +++ b/arch/arm/boot/dts/r8a7790-lager.dts
>>> @@ -144,6 +144,16 @@
>>> states = <3300000 1
>>> 1800000 0>;
>>> };
>>> +
>>> + clocks {
>>> + /* External PCIe bus clock - not used */
>>> + pcie_bus_clk: pcie_bus_clk {
>>> + compatible = "fixed-clock";
>>> + #clock-cells = <0>;
>>> + clock-frequency = <0>;
>> When this value gets filled in?
> It doesn't. On the Lager board, there is no PCIe support.
> It's needed as pcie_bus_clk is referenced from r8a7790.dtsi and without it
> you'll get build failures.
Yeah, I've figured that out after sending that email. Perhaps it makes
sense to stub this clock in the SoC's .dtsi file alike the EXTAL clock?
> Cheers
> Phil
WBR, Sergei
^ permalink raw reply [flat|nested] 6+ messages in thread* RE: [PATCH 4/8] ARM: shmobile: lager: Add dummy PCIe bus clock
2014-05-28 7:23 [PATCH 4/8] ARM: shmobile: lager: Add dummy PCIe bus clock Phil Edworthy
` (2 preceding siblings ...)
2014-05-28 17:40 ` Sergei Shtylyov
@ 2014-05-29 14:46 ` Phil Edworthy
2014-06-10 8:06 ` Phil Edworthy
4 siblings, 0 replies; 6+ messages in thread
From: Phil Edworthy @ 2014-05-29 14:46 UTC (permalink / raw)
To: linux-sh
Hi Sergei,
On 28 May 2014 18:40, Sergei wrote:
> On 05/28/2014 07:04 PM, Phil Edworthy wrote:
>
> >>> Since the CPU's dtsi refers to pcie_bus_clock, we need an entry in
> >>> the board's dts, even if we aren't using PCIe.
>
> >>> Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com>
> >>> ---
> >>> arch/arm/boot/dts/r8a7790-lager.dts | 10 ++++++++++
> >>> 1 file changed, 10 insertions(+)
>
> >>> diff --git a/arch/arm/boot/dts/r8a7790-lager.dts
> >> b/arch/arm/boot/dts/r8a7790-lager.dts
> >>> index 9becef7..6d4fe97 100644
> >>> --- a/arch/arm/boot/dts/r8a7790-lager.dts
> >>> +++ b/arch/arm/boot/dts/r8a7790-lager.dts
> >>> @@ -144,6 +144,16 @@
> >>> states = <3300000 1
> >>> 1800000 0>;
> >>> };
> >>> +
> >>> + clocks {
> >>> + /* External PCIe bus clock - not used */
> >>> + pcie_bus_clk: pcie_bus_clk {
> >>> + compatible = "fixed-clock";
> >>> + #clock-cells = <0>;
> >>> + clock-frequency = <0>;
>
> >> When this value gets filled in?
>
> > It doesn't. On the Lager board, there is no PCIe support.
>
> > It's needed as pcie_bus_clk is referenced from r8a7790.dtsi and without it
> > you'll get build failures.
>
> Yeah, I've figured that out after sending that email. Perhaps it makes
> sense to stub this clock in the SoC's .dtsi file alike the EXTAL clock?
I am not sure what's best, providing a complete fixed-clock entry in the device dtsi and allow boards to override everything about the clock, or provide an empty shell for the clock. I'm leaning towards a complete fixed-clock entry.
Thanks
Phil
^ permalink raw reply [flat|nested] 6+ messages in thread* RE: [PATCH 4/8] ARM: shmobile: lager: Add dummy PCIe bus clock
2014-05-28 7:23 [PATCH 4/8] ARM: shmobile: lager: Add dummy PCIe bus clock Phil Edworthy
` (3 preceding siblings ...)
2014-05-29 14:46 ` Phil Edworthy
@ 2014-06-10 8:06 ` Phil Edworthy
4 siblings, 0 replies; 6+ messages in thread
From: Phil Edworthy @ 2014-06-10 8:06 UTC (permalink / raw)
To: linux-sh
Hi Sergei,
On 29 May 2014 15:47, Phil Edworthy wrote:
> On 28 May 2014 18:40, Sergei wrote:
> > On 05/28/2014 07:04 PM, Phil Edworthy wrote:
> >
> > >>> Since the CPU's dtsi refers to pcie_bus_clock, we need an entry in
> > >>> the board's dts, even if we aren't using PCIe.
> >
> > >>> Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com>
> > >>> ---
> > >>> arch/arm/boot/dts/r8a7790-lager.dts | 10 ++++++++++
> > >>> 1 file changed, 10 insertions(+)
> >
> > >>> diff --git a/arch/arm/boot/dts/r8a7790-lager.dts
> > >> b/arch/arm/boot/dts/r8a7790-lager.dts
> > >>> index 9becef7..6d4fe97 100644
> > >>> --- a/arch/arm/boot/dts/r8a7790-lager.dts
> > >>> +++ b/arch/arm/boot/dts/r8a7790-lager.dts
> > >>> @@ -144,6 +144,16 @@
> > >>> states = <3300000 1
> > >>> 1800000 0>;
> > >>> };
> > >>> +
> > >>> + clocks {
> > >>> + /* External PCIe bus clock - not used */
> > >>> + pcie_bus_clk: pcie_bus_clk {
> > >>> + compatible = "fixed-clock";
> > >>> + #clock-cells = <0>;
> > >>> + clock-frequency = <0>;
> >
> > >> When this value gets filled in?
> >
> > > It doesn't. On the Lager board, there is no PCIe support.
> >
> > > It's needed as pcie_bus_clk is referenced from r8a7790.dtsi and without it
> > > you'll get build failures.
> >
> > Yeah, I've figured that out after sending that email. Perhaps it makes
> > sense to stub this clock in the SoC's .dtsi file alike the EXTAL clock?
>
> I am not sure what's best, providing a complete fixed-clock entry in the
> device dtsi and allow boards to override everything about the clock, or
> provide an empty shell for the clock. I'm leaning towards a complete fixed-
> clock entry.
Since the clock will always be 100MHz, the only reason for a board specific entry is the use of an external device to switch the clock on/off.
I guess that the best thing is to just put this in r8a7790/1.dtsi. If a board does control the clock, they can override it. Is that ok?
/* External PCIe bus clock */
pcie_bus_clk: pcie_bus_clk {
compatible = "fixed-clock";
#clock-cells = <0>;
clock-frequency = <100000000>;
clock-output-names = "pcie_bus";
};
Thanks
Phil
^ permalink raw reply [flat|nested] 6+ messages in thread