Re: [PATCH 00/25] serial: sh-sci: Add external clock and BRG Support

[Geert Uytterhoeven]

Hi Greg,

On Sun, Dec 13, 2015 at 7:43 AM, Greg Kroah-Hartman
 wrote:
> On Fri, Nov 20, 2015 at 10:09:24AM +0100, Geert Uytterhoeven wrote:
>> On Thu, Nov 19, 2015 at 7:38 PM, Geert Uytterhoeven
>>  wrote:
>> > This patch series adds support to the Renesas SCI serial driver for
>> >   - the optional external clock on (H)SCI(F) and some SCIFA, where this
>> > pin can serve as a clock input,
>> >   - the optional clock sources for the Baud Rate Generator for External
>> > Clock (BRG), as found on some SCIF variants and on HSCIF.
>> > Using external clocks increases the range and accuracy of supported baud
>> > rates. Please see the descriptions of the DTS patches for more detailed
>> > information regarding the impact on the supported platforms.
>>
>> For the consumers: I've pushed this (incl. the dependencies and a few
>> WIP patches) to the scif-brg branch of my renesas-drivers repo.
>
> I don't know what I can do with this series given the dependancies, but
> if it helps, you can add:
> Acked-by: Greg Kroah-Hartman 
> to the serial patches and take them through what ever tree you want to.

Thanks for your ackes, they make (my) life a bit simpler!

I was going to post an updated version tomorrow. I will include a list of
merge options.

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- ge...@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
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Re: [PATCH 00/25] serial: sh-sci: Add external clock and BRG Support

[Geert Uytterhoeven]

Hi Greg,

On Sun, Dec 13, 2015 at 7:43 AM, Greg Kroah-Hartman
 wrote:
> On Fri, Nov 20, 2015 at 10:09:24AM +0100, Geert Uytterhoeven wrote:
>> On Thu, Nov 19, 2015 at 7:38 PM, Geert Uytterhoeven
>>  wrote:
>> > This patch series adds support to the Renesas SCI serial driver for
>> >   - the optional external clock on (H)SCI(F) and some SCIFA, where this
>> > pin can serve as a clock input,
>> >   - the optional clock sources for the Baud Rate Generator for External
>> > Clock (BRG), as found on some SCIF variants and on HSCIF.
>> > Using external clocks increases the range and accuracy of supported baud
>> > rates. Please see the descriptions of the DTS patches for more detailed
>> > information regarding the impact on the supported platforms.
>>
>> For the consumers: I've pushed this (incl. the dependencies and a few
>> WIP patches) to the scif-brg branch of my renesas-drivers repo.
>
> I don't know what I can do with this series given the dependancies, but
> if it helps, you can add:
> Acked-by: Greg Kroah-Hartman 
> to the serial patches and take them through what ever tree you want to.

Thanks for your ackes, they make (my) life a bit simpler!

I was going to post an updated version tomorrow. I will include a list of
merge options.

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- ge...@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
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
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Please read the FAQ at  http://www.tux.org/lkml/

Re: [PATCH 00/25] serial: sh-sci: Add external clock and BRG Support

[Greg Kroah-Hartman]

On Fri, Nov 20, 2015 at 10:09:24AM +0100, Geert Uytterhoeven wrote:
> On Thu, Nov 19, 2015 at 7:38 PM, Geert Uytterhoeven
>  wrote:
> > This patch series adds support to the Renesas SCI serial driver for
> >   - the optional external clock on (H)SCI(F) and some SCIFA, where this
> > pin can serve as a clock input,
> >   - the optional clock sources for the Baud Rate Generator for External
> > Clock (BRG), as found on some SCIF variants and on HSCIF.
> > Using external clocks increases the range and accuracy of supported baud
> > rates. Please see the descriptions of the DTS patches for more detailed
> > information regarding the impact on the supported platforms.
> 
> For the consumers: I've pushed this (incl. the dependencies and a few
> WIP patches) to the scif-brg branch of my renesas-drivers repo.

I don't know what I can do with this series given the dependancies, but
if it helps, you can add:
Acked-by: Greg Kroah-Hartman 
to the serial patches and take them through what ever tree you want to.

thanks,

greg k-h
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Re: [PATCH 00/25] serial: sh-sci: Add external clock and BRG Support

[Greg Kroah-Hartman]

On Fri, Nov 20, 2015 at 10:09:24AM +0100, Geert Uytterhoeven wrote:
> On Thu, Nov 19, 2015 at 7:38 PM, Geert Uytterhoeven
>  wrote:
> > This patch series adds support to the Renesas SCI serial driver for
> >   - the optional external clock on (H)SCI(F) and some SCIFA, where this
> > pin can serve as a clock input,
> >   - the optional clock sources for the Baud Rate Generator for External
> > Clock (BRG), as found on some SCIF variants and on HSCIF.
> > Using external clocks increases the range and accuracy of supported baud
> > rates. Please see the descriptions of the DTS patches for more detailed
> > information regarding the impact on the supported platforms.
> 
> For the consumers: I've pushed this (incl. the dependencies and a few
> WIP patches) to the scif-brg branch of my renesas-drivers repo.

I don't know what I can do with this series given the dependancies, but
if it helps, you can add:
Acked-by: Greg Kroah-Hartman 
to the serial patches and take them through what ever tree you want to.

thanks,

greg k-h
--
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Re: [PATCH 00/25] serial: sh-sci: Add external clock and BRG Support

[Simon Horman]

On Thu, Nov 19, 2015 at 07:38:39PM +0100, Geert Uytterhoeven wrote:
>   Hi,
> 
> This patch series adds support to the Renesas SCI serial driver for
>   - the optional external clock on (H)SCI(F) and some SCIFA, where this
> pin can serve as a clock input,
>   - the optional clock sources for the Baud Rate Generator for External
> Clock (BRG), as found on some SCIF variants and on HSCIF.
> Using external clocks increases the range and accuracy of supported baud
> rates. Please see the descriptions of the DTS patches for more detailed
> information regarding the impact on the supported platforms.
> 
> For now this supports r8a7791/koelsch and r8a7795/salvator-x only, which
> have an external SCIF_CLK running at 14.7456 MHz.
> Support for other R-Car platforms will be added later.
> 
> Testing:
>   - The Baud Rate Generator for External Clock (BRG) was tested with
> SCIF and HSCIF on r8a7791/koelsch and r8a7795/salvator-x,
>   - The external clock input on (H)SCK was tested on r8a7795/salvator-x
> by feeding an external clock signal to (H)SCIF1,
>   - Various bit rates were monitored using a SmartScope,
>   - Regression testing was done on Renesas ARM platforms that use SCIFA
> as the console (r8a73a4/ape6evm, r8a7740/armadillo, and
> sh73a0/kzm9g).
> 
> Dependencies:
>   - This series depends on the series "[PATCH v2 00/16] serial: sh-sci:
> Clock Cleanups",
>   - The SH patch 25 depends on the "serial: sh-sci" patches in this
> series,
>   - The DTS patches 21-24 can be applied independently, once the DT
> binding patches 1-2 are accepted,

I have marked those patches as deferred pending the bindings being
accepted.

>   - r8a7791/r8a7795 has a runtime dependency on series "[PATCH 0/2]
> pinctrl: sh-pfc: r8a7791/r8a7795: Add SCIF_CLK support",
>   - r8a7795 also depends on
>- platform support in e.g. renesas-drivers-2015-11-17-v4.4-rc1,
>- "[PATCH] pinctrl: sh-pfc: r8a7795: Add HSCIF pins, groups, and
>functions",
>- "[PATCH] arm64: renesas: r8a7795 dtsi: Add all HSCIF nodes".
>   - Legacy SH has a runtime dependency on:
>   - series "[PATCH 0/2] drivers: sh: clk: Cleanup clock API",
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Re: [PATCH 00/25] serial: sh-sci: Add external clock and BRG Support

[Simon Horman]

On Thu, Nov 19, 2015 at 07:38:39PM +0100, Geert Uytterhoeven wrote:
>   Hi,
> 
> This patch series adds support to the Renesas SCI serial driver for
>   - the optional external clock on (H)SCI(F) and some SCIFA, where this
> pin can serve as a clock input,
>   - the optional clock sources for the Baud Rate Generator for External
> Clock (BRG), as found on some SCIF variants and on HSCIF.
> Using external clocks increases the range and accuracy of supported baud
> rates. Please see the descriptions of the DTS patches for more detailed
> information regarding the impact on the supported platforms.
> 
> For now this supports r8a7791/koelsch and r8a7795/salvator-x only, which
> have an external SCIF_CLK running at 14.7456 MHz.
> Support for other R-Car platforms will be added later.
> 
> Testing:
>   - The Baud Rate Generator for External Clock (BRG) was tested with
> SCIF and HSCIF on r8a7791/koelsch and r8a7795/salvator-x,
>   - The external clock input on (H)SCK was tested on r8a7795/salvator-x
> by feeding an external clock signal to (H)SCIF1,
>   - Various bit rates were monitored using a SmartScope,
>   - Regression testing was done on Renesas ARM platforms that use SCIFA
> as the console (r8a73a4/ape6evm, r8a7740/armadillo, and
> sh73a0/kzm9g).
> 
> Dependencies:
>   - This series depends on the series "[PATCH v2 00/16] serial: sh-sci:
> Clock Cleanups",
>   - The SH patch 25 depends on the "serial: sh-sci" patches in this
> series,
>   - The DTS patches 21-24 can be applied independently, once the DT
> binding patches 1-2 are accepted,

I have marked those patches as deferred pending the bindings being
accepted.

>   - r8a7791/r8a7795 has a runtime dependency on series "[PATCH 0/2]
> pinctrl: sh-pfc: r8a7791/r8a7795: Add SCIF_CLK support",
>   - r8a7795 also depends on
>- platform support in e.g. renesas-drivers-2015-11-17-v4.4-rc1,
>- "[PATCH] pinctrl: sh-pfc: r8a7795: Add HSCIF pins, groups, and
>functions",
>- "[PATCH] arm64: renesas: r8a7795 dtsi: Add all HSCIF nodes".
>   - Legacy SH has a runtime dependency on:
>   - series "[PATCH 0/2] drivers: sh: clk: Cleanup clock API",
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Re: [PATCH 00/25] serial: sh-sci: Add external clock and BRG Support

[Geert Uytterhoeven]

On Fri, Nov 20, 2015 at 3:50 PM, Laurent Pinchart
 wrote:
> On Friday 20 November 2015 10:07:31 Geert Uytterhoeven wrote:
>> On Fri, Nov 20, 2015 at 9:58 AM, Laurent Pinchart wrote:
>> > On Friday 20 November 2015 09:22:16 Geert Uytterhoeven wrote:
>> >> On Thu, Nov 19, 2015 at 10:08 PM, Laurent Pinchart wrote:
>> >>> Could you briefly explain (and even better in a source code comment)
>> >>> how you handle baud rate calculation with the chained BRGs ?
>> >>
>> >> I'll do that. Note that there's no chaining of BRGs, only muxing (so yes,
>> >> it needs more clarification ;-).
>> >
>> > Really ? I thought the BRG-EC was one possible input for the internal BRG
>> > ? Does it bypass the internal BRG ? Or do you configure the internal BRG
>> > to not divide the clock when using the BRG-EC ?
>>
>> Yes, it's bypassed.
>>
>> Cfr. SCSCR.CKE[1:0].
>> '00' means internal BRG (although the docs state P divided by 1/4/16/64),
>> '10' means SCK or SC_CLK (SCIF_CLK/INT_CLK).
>
> That's indeed simpler. Could you capture the behaviour in a source code
> comment ?

Sure.

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- ge...@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
--
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Re: [PATCH 00/25] serial: sh-sci: Add external clock and BRG Support

[Laurent Pinchart]

Hi Geert,

On Friday 20 November 2015 10:07:31 Geert Uytterhoeven wrote:
> On Fri, Nov 20, 2015 at 9:58 AM, Laurent Pinchart wrote:
> > On Friday 20 November 2015 09:22:16 Geert Uytterhoeven wrote:
> >> On Thu, Nov 19, 2015 at 10:08 PM, Laurent Pinchart wrote:
> >>> Could you briefly explain (and even better in a source code comment)
> >>> how you handle baud rate calculation with the chained BRGs ?
> >> 
> >> I'll do that. Note that there's no chaining of BRGs, only muxing (so yes,
> >> it needs more clarification ;-).
> > 
> > Really ? I thought the BRG-EC was one possible input for the internal BRG
> > ? Does it bypass the internal BRG ? Or do you configure the internal BRG
> > to not divide the clock when using the BRG-EC ?
> 
> Yes, it's bypassed.
> 
> Cfr. SCSCR.CKE[1:0].
> '00' means internal BRG (although the docs state P divided by 1/4/16/64),
> '10' means SCK or SC_CLK (SCIF_CLK/INT_CLK).

That's indeed simpler. Could you capture the behaviour in a source code 
comment ?

-- 
Regards,

Laurent Pinchart

--
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Re: [PATCH 00/25] serial: sh-sci: Add external clock and BRG Support

[Geert Uytterhoeven]

On Thu, Nov 19, 2015 at 7:38 PM, Geert Uytterhoeven
 wrote:
> This patch series adds support to the Renesas SCI serial driver for
>   - the optional external clock on (H)SCI(F) and some SCIFA, where this
> pin can serve as a clock input,
>   - the optional clock sources for the Baud Rate Generator for External
> Clock (BRG), as found on some SCIF variants and on HSCIF.
> Using external clocks increases the range and accuracy of supported baud
> rates. Please see the descriptions of the DTS patches for more detailed
> information regarding the impact on the supported platforms.

For the consumers: I've pushed this (incl. the dependencies and a few
WIP patches) to the scif-brg branch of my renesas-drivers repo.

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- ge...@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
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
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Re: [PATCH 00/25] serial: sh-sci: Add external clock and BRG Support

[Geert Uytterhoeven]

Hi Laurent,

On Fri, Nov 20, 2015 at 9:58 AM, Laurent Pinchart
 wrote:
> On Friday 20 November 2015 09:22:16 Geert Uytterhoeven wrote:
>> On Thu, Nov 19, 2015 at 10:08 PM, Laurent Pinchart wrote:
>> > Could you briefly explain (and even better in a source code comment) how
>> > you handle baud rate calculation with the chained BRGs ?
>>
>> I'll do that. Note that there's no chaining of BRGs, only muxing (so yes, it
>> needs more clarification ;-).
>
> Really ? I thought the BRG-EC was one possible input for the internal BRG ?
> Does it bypass the internal BRG ? Or do you configure the internal BRG to not
> divide the clock when using the BRG-EC ?

Yes, it's bypassed.

Cfr. SCSCR.CKE[1:0].
'00' means internal BRG (although the docs state P divided by 1/4/16/64),
'10' means SCK or SC_CLK (SCIF_CLK/INT_CLK).

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- ge...@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
--
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Please read the FAQ at  http://www.tux.org/lkml/

Re: [PATCH 00/25] serial: sh-sci: Add external clock and BRG Support

[Laurent Pinchart]

Hi Geert,

On Friday 20 November 2015 09:22:16 Geert Uytterhoeven wrote:
> On Thu, Nov 19, 2015 at 10:08 PM, Laurent Pinchart wrote:
> > For patches 3-6, 13, 15-16 and 22 and 24,
> > 
> > Reviewed-by: Laurent Pinchart 
> 
> Many thanks for your review comments!

You're welcome.

> > I'm not sure I'd bother with patch 25/25, but I'm not against merging it
> > either. I'd be surprised if the serial driver still worked at all on SH
> > :-)
> 
> It should not cause problems, as long as sh7734 doesn't add the optional
> clocks ;-)

To be clear I don't expect this patch set to break it, I expect it to be 
broken already :-)

> > On Thursday 19 November 2015 19:38:39 Geert Uytterhoeven wrote:
> >> This patch series adds support to the Renesas SCI serial driver for
> >> 
> >>   - the optional external clock on (H)SCI(F) and some SCIFA, where this
> >>   
> >> pin can serve as a clock input,
> >>   
> >>   - the optional clock sources for the Baud Rate Generator for External
> >>   
> >> Clock (BRG), as found on some SCIF variants and on HSCIF.
> > 
> > Could you briefly explain (and even better in a source code comment) how
> > you handle baud rate calculation with the chained BRGs ?
> 
> I'll do that. Note that there's no chaining of BRGs, only muxing (so yes, it
> needs more clarification ;-).

Really ? I thought the BRG-EC was one possible input for the internal BRG ? 
Does it bypass the internal BRG ? Or do you configure the internal BRG to not 
divide the clock when using the BRG-EC ?

> There can be 4 possible sources for the sampling clock:
>   1. Internal BRG (BRR register),
>   2. (H)SCK,
>   3. BRG for external clock
>   a. Using SCIF_CLK,
>   b. Using the bus clock.

-- 
Regards,

Laurent Pinchart

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Re: [PATCH 00/25] serial: sh-sci: Add external clock and BRG Support

[Geert Uytterhoeven]

Hi Laurent,

On Thu, Nov 19, 2015 at 10:08 PM, Laurent Pinchart
 wrote:
> For patches 3-6, 13, 15-16 and 22 and 24,
>
> Reviewed-by: Laurent Pinchart 

Many thanks for your review comments!

> I'm not sure I'd bother with patch 25/25, but I'm not against merging it
> either. I'd be surprised if the serial driver still worked at all on SH :-)

It should not cause problems, as long as sh7734 doesn't add the optional
clocks ;-)

> On Thursday 19 November 2015 19:38:39 Geert Uytterhoeven wrote:
>> This patch series adds support to the Renesas SCI serial driver for
>>   - the optional external clock on (H)SCI(F) and some SCIFA, where this
>> pin can serve as a clock input,
>>   - the optional clock sources for the Baud Rate Generator for External
>> Clock (BRG), as found on some SCIF variants and on HSCIF.
>
> Could you briefly explain (and even better in a source code comment) how you
> handle baud rate calculation with the chained BRGs ?

I'll do that. Note that there's no chaining of BRGs, only muxing (so yes, it
needs more clarification ;-).

There can be 4 possible sources for the sampling clock:
  1. Internal BRG (BRR register),
  2. (H)SCK,
  3. BRG for external clock
  a. Using SCIF_CLK,
  b. Using the bus clock.

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- ge...@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
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Re: [PATCH 00/25] serial: sh-sci: Add external clock and BRG Support

[Laurent Pinchart]

Hi Geert,

On Friday 20 November 2015 10:07:31 Geert Uytterhoeven wrote:
> On Fri, Nov 20, 2015 at 9:58 AM, Laurent Pinchart wrote:
> > On Friday 20 November 2015 09:22:16 Geert Uytterhoeven wrote:
> >> On Thu, Nov 19, 2015 at 10:08 PM, Laurent Pinchart wrote:
> >>> Could you briefly explain (and even better in a source code comment)
> >>> how you handle baud rate calculation with the chained BRGs ?
> >> 
> >> I'll do that. Note that there's no chaining of BRGs, only muxing (so yes,
> >> it needs more clarification ;-).
> > 
> > Really ? I thought the BRG-EC was one possible input for the internal BRG
> > ? Does it bypass the internal BRG ? Or do you configure the internal BRG
> > to not divide the clock when using the BRG-EC ?
> 
> Yes, it's bypassed.
> 
> Cfr. SCSCR.CKE[1:0].
> '00' means internal BRG (although the docs state P divided by 1/4/16/64),
> '10' means SCK or SC_CLK (SCIF_CLK/INT_CLK).

That's indeed simpler. Could you capture the behaviour in a source code 
comment ?

-- 
Regards,

Laurent Pinchart

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Re: [PATCH 00/25] serial: sh-sci: Add external clock and BRG Support

[Geert Uytterhoeven]

On Fri, Nov 20, 2015 at 3:50 PM, Laurent Pinchart
 wrote:
> On Friday 20 November 2015 10:07:31 Geert Uytterhoeven wrote:
>> On Fri, Nov 20, 2015 at 9:58 AM, Laurent Pinchart wrote:
>> > On Friday 20 November 2015 09:22:16 Geert Uytterhoeven wrote:
>> >> On Thu, Nov 19, 2015 at 10:08 PM, Laurent Pinchart wrote:
>> >>> Could you briefly explain (and even better in a source code comment)
>> >>> how you handle baud rate calculation with the chained BRGs ?
>> >>
>> >> I'll do that. Note that there's no chaining of BRGs, only muxing (so yes,
>> >> it needs more clarification ;-).
>> >
>> > Really ? I thought the BRG-EC was one possible input for the internal BRG
>> > ? Does it bypass the internal BRG ? Or do you configure the internal BRG
>> > to not divide the clock when using the BRG-EC ?
>>
>> Yes, it's bypassed.
>>
>> Cfr. SCSCR.CKE[1:0].
>> '00' means internal BRG (although the docs state P divided by 1/4/16/64),
>> '10' means SCK or SC_CLK (SCIF_CLK/INT_CLK).
>
> That's indeed simpler. Could you capture the behaviour in a source code
> comment ?

Sure.

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- ge...@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
--
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Re: [PATCH 00/25] serial: sh-sci: Add external clock and BRG Support

[Laurent Pinchart]

Hi Geert,

On Friday 20 November 2015 09:22:16 Geert Uytterhoeven wrote:
> On Thu, Nov 19, 2015 at 10:08 PM, Laurent Pinchart wrote:
> > For patches 3-6, 13, 15-16 and 22 and 24,
> > 
> > Reviewed-by: Laurent Pinchart 
> 
> Many thanks for your review comments!

You're welcome.

> > I'm not sure I'd bother with patch 25/25, but I'm not against merging it
> > either. I'd be surprised if the serial driver still worked at all on SH
> > :-)
> 
> It should not cause problems, as long as sh7734 doesn't add the optional
> clocks ;-)

To be clear I don't expect this patch set to break it, I expect it to be 
broken already :-)

> > On Thursday 19 November 2015 19:38:39 Geert Uytterhoeven wrote:
> >> This patch series adds support to the Renesas SCI serial driver for
> >> 
> >>   - the optional external clock on (H)SCI(F) and some SCIFA, where this
> >>   
> >> pin can serve as a clock input,
> >>   
> >>   - the optional clock sources for the Baud Rate Generator for External
> >>   
> >> Clock (BRG), as found on some SCIF variants and on HSCIF.
> > 
> > Could you briefly explain (and even better in a source code comment) how
> > you handle baud rate calculation with the chained BRGs ?
> 
> I'll do that. Note that there's no chaining of BRGs, only muxing (so yes, it
> needs more clarification ;-).

Really ? I thought the BRG-EC was one possible input for the internal BRG ? 
Does it bypass the internal BRG ? Or do you configure the internal BRG to not 
divide the clock when using the BRG-EC ?

> There can be 4 possible sources for the sampling clock:
>   1. Internal BRG (BRR register),
>   2. (H)SCK,
>   3. BRG for external clock
>   a. Using SCIF_CLK,
>   b. Using the bus clock.

-- 
Regards,

Laurent Pinchart

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Re: [PATCH 00/25] serial: sh-sci: Add external clock and BRG Support

[Geert Uytterhoeven]

Hi Laurent,

On Fri, Nov 20, 2015 at 9:58 AM, Laurent Pinchart
 wrote:
> On Friday 20 November 2015 09:22:16 Geert Uytterhoeven wrote:
>> On Thu, Nov 19, 2015 at 10:08 PM, Laurent Pinchart wrote:
>> > Could you briefly explain (and even better in a source code comment) how
>> > you handle baud rate calculation with the chained BRGs ?
>>
>> I'll do that. Note that there's no chaining of BRGs, only muxing (so yes, it
>> needs more clarification ;-).
>
> Really ? I thought the BRG-EC was one possible input for the internal BRG ?
> Does it bypass the internal BRG ? Or do you configure the internal BRG to not
> divide the clock when using the BRG-EC ?

Yes, it's bypassed.

Cfr. SCSCR.CKE[1:0].
'00' means internal BRG (although the docs state P divided by 1/4/16/64),
'10' means SCK or SC_CLK (SCIF_CLK/INT_CLK).

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- ge...@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
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Re: [PATCH 00/25] serial: sh-sci: Add external clock and BRG Support

[Geert Uytterhoeven]

On Thu, Nov 19, 2015 at 7:38 PM, Geert Uytterhoeven
 wrote:
> This patch series adds support to the Renesas SCI serial driver for
>   - the optional external clock on (H)SCI(F) and some SCIFA, where this
> pin can serve as a clock input,
>   - the optional clock sources for the Baud Rate Generator for External
> Clock (BRG), as found on some SCIF variants and on HSCIF.
> Using external clocks increases the range and accuracy of supported baud
> rates. Please see the descriptions of the DTS patches for more detailed
> information regarding the impact on the supported platforms.

For the consumers: I've pushed this (incl. the dependencies and a few
WIP patches) to the scif-brg branch of my renesas-drivers repo.

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- ge...@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
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Re: [PATCH 00/25] serial: sh-sci: Add external clock and BRG Support

[Geert Uytterhoeven]

Hi Laurent,

On Thu, Nov 19, 2015 at 10:08 PM, Laurent Pinchart
 wrote:
> For patches 3-6, 13, 15-16 and 22 and 24,
>
> Reviewed-by: Laurent Pinchart 

Many thanks for your review comments!

> I'm not sure I'd bother with patch 25/25, but I'm not against merging it
> either. I'd be surprised if the serial driver still worked at all on SH :-)

It should not cause problems, as long as sh7734 doesn't add the optional
clocks ;-)

> On Thursday 19 November 2015 19:38:39 Geert Uytterhoeven wrote:
>> This patch series adds support to the Renesas SCI serial driver for
>>   - the optional external clock on (H)SCI(F) and some SCIFA, where this
>> pin can serve as a clock input,
>>   - the optional clock sources for the Baud Rate Generator for External
>> Clock (BRG), as found on some SCIF variants and on HSCIF.
>
> Could you briefly explain (and even better in a source code comment) how you
> handle baud rate calculation with the chained BRGs ?

I'll do that. Note that there's no chaining of BRGs, only muxing (so yes, it
needs more clarification ;-).

There can be 4 possible sources for the sampling clock:
  1. Internal BRG (BRR register),
  2. (H)SCK,
  3. BRG for external clock
  a. Using SCIF_CLK,
  b. Using the bus clock.

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- ge...@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
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Re: [PATCH 00/25] serial: sh-sci: Add external clock and BRG Support

[Laurent Pinchart]

Hi Geert,

Thank you for the patches.

For patches 3-6, 13, 15-16 and 22 and 24,

Reviewed-by: Laurent Pinchart 

I'm not sure I'd bother with patch 25/25, but I'm not against merging it 
either. I'd be surprised if the serial driver still worked at all on SH :-)

On Thursday 19 November 2015 19:38:39 Geert Uytterhoeven wrote:
>   Hi,
> 
> This patch series adds support to the Renesas SCI serial driver for
>   - the optional external clock on (H)SCI(F) and some SCIFA, where this
> pin can serve as a clock input,
>   - the optional clock sources for the Baud Rate Generator for External
> Clock (BRG), as found on some SCIF variants and on HSCIF.

Could you briefly explain (and even better in a source code comment) how you 
handle baud rate calculation with the chained BRGs ?

> Using external clocks increases the range and accuracy of supported baud
> rates. Please see the descriptions of the DTS patches for more detailed
> information regarding the impact on the supported platforms.
> 
> For now this supports r8a7791/koelsch and r8a7795/salvator-x only, which
> have an external SCIF_CLK running at 14.7456 MHz.
> Support for other R-Car platforms will be added later.
> 
> Testing:
>   - The Baud Rate Generator for External Clock (BRG) was tested with
> SCIF and HSCIF on r8a7791/koelsch and r8a7795/salvator-x,
>   - The external clock input on (H)SCK was tested on r8a7795/salvator-x
> by feeding an external clock signal to (H)SCIF1,
>   - Various bit rates were monitored using a SmartScope,
>   - Regression testing was done on Renesas ARM platforms that use SCIFA
> as the console (r8a73a4/ape6evm, r8a7740/armadillo, and
> sh73a0/kzm9g).
> 
> Dependencies:
>   - This series depends on the series "[PATCH v2 00/16] serial: sh-sci:
> Clock Cleanups",
>   - The SH patch 25 depends on the "serial: sh-sci" patches in this
> series,
>   - The DTS patches 21-24 can be applied independently, once the DT
> binding patches 1-2 are accepted,
>   - r8a7791/r8a7795 has a runtime dependency on series "[PATCH 0/2]
> pinctrl: sh-pfc: r8a7791/r8a7795: Add SCIF_CLK support",
>   - r8a7795 also depends on
>- platform support in e.g. renesas-drivers-2015-11-17-v4.4-rc1,
>- "[PATCH] pinctrl: sh-pfc: r8a7795: Add HSCIF pins, groups, and
>functions",
>- "[PATCH] arm64: renesas: r8a7795 dtsi: Add all HSCIF nodes".
>   - Legacy SH has a runtime dependency on:
>   - series "[PATCH 0/2] drivers: sh: clk: Cleanup clock API",
> 
> Thanks for your comments!
> 
> Geert Uytterhoeven (25):
>   serial: sh-sci: Update DT binding documentation for external clock
> input
>   serial: sh-sci: Update DT binding documentation for BRG support
>   serial: sh-sci: Drop useless check for zero sampling_rate
>   serial: sh-sci: Grammar s/Get ... for/Get ... from/
>   serial: sh-sci: Drop unused frame_len parameter for
> sci_baud_calc_hscif()
>   serial: sh-sci: Don't overwrite clock selection in
> serial_console_write()
>   serial: sh-sci: Convert from clk_get() to devm_clk_get()
>   serial: sh-sci: Make unsigned values in sci_baud_calc_hscif() unsigned
>   serial: sh-sci: Avoid overflow in sci_baud_calc_hscif()
>   serial: sh-sci: Improve bit rate error calculation for HSCIF
>   serial: sh-sci: Avoid calculating the receive margin for HSCIF
>   serial: sh-sci: Merge sci_scbrr_calc() and sci_baud_calc_hscif()
>   serial: sh-sci: Take into account sampling rate for max baud rate
>   serial: sh-sci: Add BRG register definitions
>   serial: sh-sci: Replace struct sci_port_info by type/regtype encoding
>   serial: sh-sci: Correct SCIF type on RZ/A1H
>   serial: sh-sci: Correct SCIF type on R-Car for BRG
>   serial: sh-sci: Prepare for multiple clocks and baud rate generators
>   serial: sh-sci: Add support for optional external (H)SCK input
>   serial: sh-sci: Add support for optional BRG on (H)SCIF
>   ARM: shmobile: r8a7791 dtsi: Add BRG support for (H)SCIF
>   ARM: shmobile: koelsch dts: Enable SCIF_CLK frequency and pins
>   arm64: renesas: r8a7795 dtsi: Add BRG support for (H)SCIF
>   arm64: renesas: salvator-x dts: Enable SCIF_CLK frequency and pins
>   sh: sh7734: Correct SCIF type for BRG
> 
>  .../bindings/serial/renesas,sci-serial.txt |   9 +
>  arch/arm/boot/dts/r8a7791-koelsch.dts  |  13 +
>  arch/arm/boot/dts/r8a7791.dtsi |  54 ++-
>  arch/arm64/boot/dts/renesas/r8a7795-salvator-x.dts |  12 +
>  arch/arm64/boot/dts/renesas/r8a7795.dtsi   |  74 ++-
>  arch/sh/kernel/cpu/sh4a/setup-sh7734.c |  12 +-
>  drivers/tty/serial/sh-sci.c| 530 --
>  drivers/tty/serial/sh-sci.h|   5 +
>  include/linux/serial_sci.h |   1 +
>  9 files changed, 508 insertions(+), 202 deletions(-)

-- 
Regards,

Laurent Pinchart

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
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[PATCH 00/25] serial: sh-sci: Add external clock and BRG Support

[Geert Uytterhoeven]

Hi,

This patch series adds support to the Renesas SCI serial driver for
  - the optional external clock on (H)SCI(F) and some SCIFA, where this
pin can serve as a clock input,
  - the optional clock sources for the Baud Rate Generator for External
Clock (BRG), as found on some SCIF variants and on HSCIF.
Using external clocks increases the range and accuracy of supported baud
rates. Please see the descriptions of the DTS patches for more detailed
information regarding the impact on the supported platforms.

For now this supports r8a7791/koelsch and r8a7795/salvator-x only, which
have an external SCIF_CLK running at 14.7456 MHz.
Support for other R-Car platforms will be added later.

Testing:
  - The Baud Rate Generator for External Clock (BRG) was tested with
SCIF and HSCIF on r8a7791/koelsch and r8a7795/salvator-x,
  - The external clock input on (H)SCK was tested on r8a7795/salvator-x
by feeding an external clock signal to (H)SCIF1,
  - Various bit rates were monitored using a SmartScope,
  - Regression testing was done on Renesas ARM platforms that use SCIFA
as the console (r8a73a4/ape6evm, r8a7740/armadillo, and
sh73a0/kzm9g).
  
Dependencies:
  - This series depends on the series "[PATCH v2 00/16] serial: sh-sci:
Clock Cleanups",
  - The SH patch 25 depends on the "serial: sh-sci" patches in this
series,
  - The DTS patches 21-24 can be applied independently, once the DT
binding patches 1-2 are accepted,
  - r8a7791/r8a7795 has a runtime dependency on series "[PATCH 0/2]
pinctrl: sh-pfc: r8a7791/r8a7795: Add SCIF_CLK support",
  - r8a7795 also depends on
   - platform support in e.g. renesas-drivers-2015-11-17-v4.4-rc1,
   - "[PATCH] pinctrl: sh-pfc: r8a7795: Add HSCIF pins, groups, and
 functions",
   - "[PATCH] arm64: renesas: r8a7795 dtsi: Add all HSCIF nodes".
  - Legacy SH has a runtime dependency on:
  - series "[PATCH 0/2] drivers: sh: clk: Cleanup clock API",

Thanks for your comments!

Geert Uytterhoeven (25):
  serial: sh-sci: Update DT binding documentation for external clock
input
  serial: sh-sci: Update DT binding documentation for BRG support
  serial: sh-sci: Drop useless check for zero sampling_rate
  serial: sh-sci: Grammar s/Get ... for/Get ... from/
  serial: sh-sci: Drop unused frame_len parameter for
sci_baud_calc_hscif()
  serial: sh-sci: Don't overwrite clock selection in
serial_console_write()
  serial: sh-sci: Convert from clk_get() to devm_clk_get()
  serial: sh-sci: Make unsigned values in sci_baud_calc_hscif() unsigned
  serial: sh-sci: Avoid overflow in sci_baud_calc_hscif()
  serial: sh-sci: Improve bit rate error calculation for HSCIF
  serial: sh-sci: Avoid calculating the receive margin for HSCIF
  serial: sh-sci: Merge sci_scbrr_calc() and sci_baud_calc_hscif()
  serial: sh-sci: Take into account sampling rate for max baud rate
  serial: sh-sci: Add BRG register definitions
  serial: sh-sci: Replace struct sci_port_info by type/regtype encoding
  serial: sh-sci: Correct SCIF type on RZ/A1H
  serial: sh-sci: Correct SCIF type on R-Car for BRG
  serial: sh-sci: Prepare for multiple clocks and baud rate generators
  serial: sh-sci: Add support for optional external (H)SCK input
  serial: sh-sci: Add support for optional BRG on (H)SCIF
  ARM: shmobile: r8a7791 dtsi: Add BRG support for (H)SCIF
  ARM: shmobile: koelsch dts: Enable SCIF_CLK frequency and pins
  arm64: renesas: r8a7795 dtsi: Add BRG support for (H)SCIF
  arm64: renesas: salvator-x dts: Enable SCIF_CLK frequency and pins
  sh: sh7734: Correct SCIF type for BRG

 .../bindings/serial/renesas,sci-serial.txt |   9 +
 arch/arm/boot/dts/r8a7791-koelsch.dts  |  13 +
 arch/arm/boot/dts/r8a7791.dtsi |  54 ++-
 arch/arm64/boot/dts/renesas/r8a7795-salvator-x.dts |  12 +
 arch/arm64/boot/dts/renesas/r8a7795.dtsi   |  74 ++-
 arch/sh/kernel/cpu/sh4a/setup-sh7734.c |  12 +-
 drivers/tty/serial/sh-sci.c| 530 +++--
 drivers/tty/serial/sh-sci.h|   5 +
 include/linux/serial_sci.h |   1 +
 9 files changed, 508 insertions(+), 202 deletions(-)

-- 
1.9.1

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- ge...@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
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[PATCH 00/25] serial: sh-sci: Add external clock and BRG Support

[Geert Uytterhoeven]

Hi,

This patch series adds support to the Renesas SCI serial driver for
  - the optional external clock on (H)SCI(F) and some SCIFA, where this
pin can serve as a clock input,
  - the optional clock sources for the Baud Rate Generator for External
Clock (BRG), as found on some SCIF variants and on HSCIF.
Using external clocks increases the range and accuracy of supported baud
rates. Please see the descriptions of the DTS patches for more detailed
information regarding the impact on the supported platforms.

For now this supports r8a7791/koelsch and r8a7795/salvator-x only, which
have an external SCIF_CLK running at 14.7456 MHz.
Support for other R-Car platforms will be added later.

Testing:
  - The Baud Rate Generator for External Clock (BRG) was tested with
SCIF and HSCIF on r8a7791/koelsch and r8a7795/salvator-x,
  - The external clock input on (H)SCK was tested on r8a7795/salvator-x
by feeding an external clock signal to (H)SCIF1,
  - Various bit rates were monitored using a SmartScope,
  - Regression testing was done on Renesas ARM platforms that use SCIFA
as the console (r8a73a4/ape6evm, r8a7740/armadillo, and
sh73a0/kzm9g).
  
Dependencies:
  - This series depends on the series "[PATCH v2 00/16] serial: sh-sci:
Clock Cleanups",
  - The SH patch 25 depends on the "serial: sh-sci" patches in this
series,
  - The DTS patches 21-24 can be applied independently, once the DT
binding patches 1-2 are accepted,
  - r8a7791/r8a7795 has a runtime dependency on series "[PATCH 0/2]
pinctrl: sh-pfc: r8a7791/r8a7795: Add SCIF_CLK support",
  - r8a7795 also depends on
   - platform support in e.g. renesas-drivers-2015-11-17-v4.4-rc1,
   - "[PATCH] pinctrl: sh-pfc: r8a7795: Add HSCIF pins, groups, and
 functions",
   - "[PATCH] arm64: renesas: r8a7795 dtsi: Add all HSCIF nodes".
  - Legacy SH has a runtime dependency on:
  - series "[PATCH 0/2] drivers: sh: clk: Cleanup clock API",

Thanks for your comments!

Geert Uytterhoeven (25):
  serial: sh-sci: Update DT binding documentation for external clock
input
  serial: sh-sci: Update DT binding documentation for BRG support
  serial: sh-sci: Drop useless check for zero sampling_rate
  serial: sh-sci: Grammar s/Get ... for/Get ... from/
  serial: sh-sci: Drop unused frame_len parameter for
sci_baud_calc_hscif()
  serial: sh-sci: Don't overwrite clock selection in
serial_console_write()
  serial: sh-sci: Convert from clk_get() to devm_clk_get()
  serial: sh-sci: Make unsigned values in sci_baud_calc_hscif() unsigned
  serial: sh-sci: Avoid overflow in sci_baud_calc_hscif()
  serial: sh-sci: Improve bit rate error calculation for HSCIF
  serial: sh-sci: Avoid calculating the receive margin for HSCIF
  serial: sh-sci: Merge sci_scbrr_calc() and sci_baud_calc_hscif()
  serial: sh-sci: Take into account sampling rate for max baud rate
  serial: sh-sci: Add BRG register definitions
  serial: sh-sci: Replace struct sci_port_info by type/regtype encoding
  serial: sh-sci: Correct SCIF type on RZ/A1H
  serial: sh-sci: Correct SCIF type on R-Car for BRG
  serial: sh-sci: Prepare for multiple clocks and baud rate generators
  serial: sh-sci: Add support for optional external (H)SCK input
  serial: sh-sci: Add support for optional BRG on (H)SCIF
  ARM: shmobile: r8a7791 dtsi: Add BRG support for (H)SCIF
  ARM: shmobile: koelsch dts: Enable SCIF_CLK frequency and pins
  arm64: renesas: r8a7795 dtsi: Add BRG support for (H)SCIF
  arm64: renesas: salvator-x dts: Enable SCIF_CLK frequency and pins
  sh: sh7734: Correct SCIF type for BRG

 .../bindings/serial/renesas,sci-serial.txt |   9 +
 arch/arm/boot/dts/r8a7791-koelsch.dts  |  13 +
 arch/arm/boot/dts/r8a7791.dtsi |  54 ++-
 arch/arm64/boot/dts/renesas/r8a7795-salvator-x.dts |  12 +
 arch/arm64/boot/dts/renesas/r8a7795.dtsi   |  74 ++-
 arch/sh/kernel/cpu/sh4a/setup-sh7734.c |  12 +-
 drivers/tty/serial/sh-sci.c| 530 +++--
 drivers/tty/serial/sh-sci.h|   5 +
 include/linux/serial_sci.h |   1 +
 9 files changed, 508 insertions(+), 202 deletions(-)

-- 
1.9.1

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- ge...@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
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Re: [PATCH 00/25] serial: sh-sci: Add external clock and BRG Support

[Laurent Pinchart]

Hi Geert,

Thank you for the patches.

For patches 3-6, 13, 15-16 and 22 and 24,

Reviewed-by: Laurent Pinchart 

I'm not sure I'd bother with patch 25/25, but I'm not against merging it 
either. I'd be surprised if the serial driver still worked at all on SH :-)

On Thursday 19 November 2015 19:38:39 Geert Uytterhoeven wrote:
>   Hi,
> 
> This patch series adds support to the Renesas SCI serial driver for
>   - the optional external clock on (H)SCI(F) and some SCIFA, where this
> pin can serve as a clock input,
>   - the optional clock sources for the Baud Rate Generator for External
> Clock (BRG), as found on some SCIF variants and on HSCIF.

Could you briefly explain (and even better in a source code comment) how you 
handle baud rate calculation with the chained BRGs ?

> Using external clocks increases the range and accuracy of supported baud
> rates. Please see the descriptions of the DTS patches for more detailed
> information regarding the impact on the supported platforms.
> 
> For now this supports r8a7791/koelsch and r8a7795/salvator-x only, which
> have an external SCIF_CLK running at 14.7456 MHz.
> Support for other R-Car platforms will be added later.
> 
> Testing:
>   - The Baud Rate Generator for External Clock (BRG) was tested with
> SCIF and HSCIF on r8a7791/koelsch and r8a7795/salvator-x,
>   - The external clock input on (H)SCK was tested on r8a7795/salvator-x
> by feeding an external clock signal to (H)SCIF1,
>   - Various bit rates were monitored using a SmartScope,
>   - Regression testing was done on Renesas ARM platforms that use SCIFA
> as the console (r8a73a4/ape6evm, r8a7740/armadillo, and
> sh73a0/kzm9g).
> 
> Dependencies:
>   - This series depends on the series "[PATCH v2 00/16] serial: sh-sci:
> Clock Cleanups",
>   - The SH patch 25 depends on the "serial: sh-sci" patches in this
> series,
>   - The DTS patches 21-24 can be applied independently, once the DT
> binding patches 1-2 are accepted,
>   - r8a7791/r8a7795 has a runtime dependency on series "[PATCH 0/2]
> pinctrl: sh-pfc: r8a7791/r8a7795: Add SCIF_CLK support",
>   - r8a7795 also depends on
>- platform support in e.g. renesas-drivers-2015-11-17-v4.4-rc1,
>- "[PATCH] pinctrl: sh-pfc: r8a7795: Add HSCIF pins, groups, and
>functions",
>- "[PATCH] arm64: renesas: r8a7795 dtsi: Add all HSCIF nodes".
>   - Legacy SH has a runtime dependency on:
>   - series "[PATCH 0/2] drivers: sh: clk: Cleanup clock API",
> 
> Thanks for your comments!
> 
> Geert Uytterhoeven (25):
>   serial: sh-sci: Update DT binding documentation for external clock
> input
>   serial: sh-sci: Update DT binding documentation for BRG support
>   serial: sh-sci: Drop useless check for zero sampling_rate
>   serial: sh-sci: Grammar s/Get ... for/Get ... from/
>   serial: sh-sci: Drop unused frame_len parameter for
> sci_baud_calc_hscif()
>   serial: sh-sci: Don't overwrite clock selection in
> serial_console_write()
>   serial: sh-sci: Convert from clk_get() to devm_clk_get()
>   serial: sh-sci: Make unsigned values in sci_baud_calc_hscif() unsigned
>   serial: sh-sci: Avoid overflow in sci_baud_calc_hscif()
>   serial: sh-sci: Improve bit rate error calculation for HSCIF
>   serial: sh-sci: Avoid calculating the receive margin for HSCIF
>   serial: sh-sci: Merge sci_scbrr_calc() and sci_baud_calc_hscif()
>   serial: sh-sci: Take into account sampling rate for max baud rate
>   serial: sh-sci: Add BRG register definitions
>   serial: sh-sci: Replace struct sci_port_info by type/regtype encoding
>   serial: sh-sci: Correct SCIF type on RZ/A1H
>   serial: sh-sci: Correct SCIF type on R-Car for BRG
>   serial: sh-sci: Prepare for multiple clocks and baud rate generators
>   serial: sh-sci: Add support for optional external (H)SCK input
>   serial: sh-sci: Add support for optional BRG on (H)SCIF
>   ARM: shmobile: r8a7791 dtsi: Add BRG support for (H)SCIF
>   ARM: shmobile: koelsch dts: Enable SCIF_CLK frequency and pins
>   arm64: renesas: r8a7795 dtsi: Add BRG support for (H)SCIF
>   arm64: renesas: salvator-x dts: Enable SCIF_CLK frequency and pins
>   sh: sh7734: Correct SCIF type for BRG
> 
>  .../bindings/serial/renesas,sci-serial.txt |   9 +
>  arch/arm/boot/dts/r8a7791-koelsch.dts  |  13 +
>  arch/arm/boot/dts/r8a7791.dtsi |  54 ++-
>  arch/arm64/boot/dts/renesas/r8a7795-salvator-x.dts |  12 +
>  arch/arm64/boot/dts/renesas/r8a7795.dtsi   |  74 ++-
>  arch/sh/kernel/cpu/sh4a/setup-sh7734.c |  12 +-
>  drivers/tty/serial/sh-sci.c| 530 --
>  drivers/tty/serial/sh-sci.h|   5 +
>  include/linux/serial_sci.h |   1 +
>  9 files changed, 508 insertions(+), 202 deletions(-)

-- 
Regards,

Laurent Pinchart

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