mbox series

[v2,0/5] Add support for Airoha EN7523 SoC

Message ID 20210907102722.47543-1-bert@biot.com
Headers show
Series Add support for Airoha EN7523 SoC | expand

Message

Bert Vermeulen Sept. 7, 2021, 10:27 a.m. UTC
This patchset adds support for the Airoha EN7523 SoC, intended primarily
for xPON/xDSL routers.

v2:
- The company changed name from EcoNet to Airoha.
- Removed Makefile text offset in lieu of /memreserve/ DTS node (see
  https://lists.infradead.org/pipermail/linux-arm-kernel/2021-September/681898.html)
- DTS: Moved /memory node, fixed CPU compatible, removed GIC_CPU_MASK_SIMPLE
  from timer interrupts node, changed timer compatible, and minor fixes.

John Crispin (5):
  dt-bindings: Add vendor prefix for Airoha
  dt-bindings: arm: airoha: Add binding for EN7523 SoC and EVB
  ARM: dts: Add basic support for Airoha EN7523
  ARM: Add basic support for Airoha EN7523 SoC
  ARM: multi_v7_defconfig: Add support for Airoha EN7523 SoC

 .../devicetree/bindings/arm/airoha.yaml       |  27 +++++
 .../devicetree/bindings/vendor-prefixes.yaml  |   2 +
 arch/arm/Kconfig                              |  14 +++
 arch/arm/boot/dts/Makefile                    |   2 +
 arch/arm/boot/dts/en7523-evb.dts              |  26 ++++
 arch/arm/boot/dts/en7523.dtsi                 | 114 ++++++++++++++++++
 arch/arm/configs/multi_v7_defconfig           |   2 +
 7 files changed, 187 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/arm/airoha.yaml
 create mode 100644 arch/arm/boot/dts/en7523-evb.dts
 create mode 100644 arch/arm/boot/dts/en7523.dtsi

Comments

Dmitry Osipenko Sept. 7, 2021, 10:39 a.m. UTC | #1
07.09.2021 13:27, Bert Vermeulen пишет:
> From: John Crispin <john@phrozen.org>
> 
> This enables basic bootup support for the Airoha EN7523 SoC.
> 
> Signed-off-by: John Crispin <john@phrozen.org>
> Signed-off-by: Bert Vermeulen <bert@biot.com>
> ---
>  arch/arm/configs/multi_v7_defconfig | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/arch/arm/configs/multi_v7_defconfig b/arch/arm/configs/multi_v7_defconfig
> index d9abaae118dd..a9370a95dc38 100644
> --- a/arch/arm/configs/multi_v7_defconfig
> +++ b/arch/arm/configs/multi_v7_defconfig
> @@ -31,6 +31,7 @@ CONFIG_MACH_BERLIN_BG2=y
>  CONFIG_MACH_BERLIN_BG2CD=y
>  CONFIG_MACH_BERLIN_BG2Q=y
>  CONFIG_ARCH_DIGICOLOR=y
> +CONFIG_ARCH_AIROHA=y
>  CONFIG_ARCH_EXYNOS=y
>  CONFIG_ARCH_HIGHBANK=y
>  CONFIG_ARCH_HISI=y
> @@ -983,6 +984,7 @@ CONFIG_STAGING_BOARD=y
>  CONFIG_MFD_CROS_EC_DEV=m
>  CONFIG_CROS_EC_I2C=m
>  CONFIG_CROS_EC_SPI=m
> +CONFIG_COMMON_CLK_EN7523=y

If SoC doesn't work without clk support, then this option should be
auto-selected by the arch option.

It also doesn't look like upstream kernel has COMMON_CLK_EN7523 at all.
Bert Vermeulen Sept. 7, 2021, 10:41 a.m. UTC | #2
On 9/7/21 12:39 PM, Dmitry Osipenko wrote:
> 07.09.2021 13:27, Bert Vermeulen пишет:
>> From: John Crispin <john@phrozen.org>
>> 
>> This enables basic bootup support for the Airoha EN7523 SoC.
>> 
>> Signed-off-by: John Crispin <john@phrozen.org>
>> Signed-off-by: Bert Vermeulen <bert@biot.com>
>> ---
>>  arch/arm/configs/multi_v7_defconfig | 2 ++
>>  1 file changed, 2 insertions(+)
>> 
>> diff --git a/arch/arm/configs/multi_v7_defconfig b/arch/arm/configs/multi_v7_defconfig
>> index d9abaae118dd..a9370a95dc38 100644
>> --- a/arch/arm/configs/multi_v7_defconfig
>> +++ b/arch/arm/configs/multi_v7_defconfig
>> @@ -31,6 +31,7 @@ CONFIG_MACH_BERLIN_BG2=y
>>  CONFIG_MACH_BERLIN_BG2CD=y
>>  CONFIG_MACH_BERLIN_BG2Q=y
>>  CONFIG_ARCH_DIGICOLOR=y
>> +CONFIG_ARCH_AIROHA=y
>>  CONFIG_ARCH_EXYNOS=y
>>  CONFIG_ARCH_HIGHBANK=y
>>  CONFIG_ARCH_HISI=y
>> @@ -983,6 +984,7 @@ CONFIG_STAGING_BOARD=y
>>  CONFIG_MFD_CROS_EC_DEV=m
>>  CONFIG_CROS_EC_I2C=m
>>  CONFIG_CROS_EC_SPI=m
>> +CONFIG_COMMON_CLK_EN7523=y
> 
> If SoC doesn't work without clk support, then this option should be
> auto-selected by the arch option.
> 
> It also doesn't look like upstream kernel has COMMON_CLK_EN7523 at all.

Oops, you're right -- the clock driver is coming as soon as the base system 
is in. I guess this option (under ARCH_AIROHA) should come in at that time 
as well? I'll respin after some more comments.
Daniel Palmer Sept. 7, 2021, 10:48 a.m. UTC | #3
Hi Bert,

On Tue, 7 Sept 2021 at 19:30, Bert Vermeulen <bert@biot.com> wrote:
>
> From: John Crispin <john@phrozen.org>
>
> EN7523 is an armv7 based silicon used inside broadband access type devices
> such as xPON and xDSL. It shares various silicon blocks with MediaTek
> silicon such as the MT7622.

This is a Cortex A53 isn't it? So it's ARMv8. I thought the issue is
that it's actually a 64bit system but you only have a 32bit
bootloader, firmware etc?

Off-topic but related:  Another MediaTek spin off, SigmaStar, seems to
have done exactly the same thing. Cortex A53 chip running as a 32bit
system to avoid having to fix their software. I'm interested to see if
this makes it into arm or arm64. :)

Cheers,

Daniel
Dmitry Osipenko Sept. 7, 2021, 11:03 a.m. UTC | #4
07.09.2021 13:41, Bert Vermeulen пишет:
> On 9/7/21 12:39 PM, Dmitry Osipenko wrote:
>> 07.09.2021 13:27, Bert Vermeulen пишет:
>>> From: John Crispin <john@phrozen.org>
>>>
>>> This enables basic bootup support for the Airoha EN7523 SoC.
>>>
>>> Signed-off-by: John Crispin <john@phrozen.org>
>>> Signed-off-by: Bert Vermeulen <bert@biot.com>
>>> ---
>>>  arch/arm/configs/multi_v7_defconfig | 2 ++
>>>  1 file changed, 2 insertions(+)
>>>
>>> diff --git a/arch/arm/configs/multi_v7_defconfig
>>> b/arch/arm/configs/multi_v7_defconfig
>>> index d9abaae118dd..a9370a95dc38 100644
>>> --- a/arch/arm/configs/multi_v7_defconfig
>>> +++ b/arch/arm/configs/multi_v7_defconfig
>>> @@ -31,6 +31,7 @@ CONFIG_MACH_BERLIN_BG2=y
>>>  CONFIG_MACH_BERLIN_BG2CD=y
>>>  CONFIG_MACH_BERLIN_BG2Q=y
>>>  CONFIG_ARCH_DIGICOLOR=y
>>> +CONFIG_ARCH_AIROHA=y
>>>  CONFIG_ARCH_EXYNOS=y
>>>  CONFIG_ARCH_HIGHBANK=y
>>>  CONFIG_ARCH_HISI=y
>>> @@ -983,6 +984,7 @@ CONFIG_STAGING_BOARD=y
>>>  CONFIG_MFD_CROS_EC_DEV=m
>>>  CONFIG_CROS_EC_I2C=m
>>>  CONFIG_CROS_EC_SPI=m
>>> +CONFIG_COMMON_CLK_EN7523=y
>>
>> If SoC doesn't work without clk support, then this option should be
>> auto-selected by the arch option.
>>
>> It also doesn't look like upstream kernel has COMMON_CLK_EN7523 at all.
> 
> Oops, you're right -- the clock driver is coming as soon as the base
> system is in. I guess this option (under ARCH_AIROHA) should come in at
> that time as well? I'll respin after some more comments.

Probably. You may also make clk driver to use ARCH_AIROHA option
directly if driver is supposed to be used only by that single arch, like
some other platform do that.
Arnd Bergmann Sept. 7, 2021, 11:51 a.m. UTC | #5
On Tue, Sep 7, 2021 at 12:48 PM Daniel Palmer <daniel@0x0f.com> wrote:
> On Tue, 7 Sept 2021 at 19:30, Bert Vermeulen <bert@biot.com> wrote:
> >
> > From: John Crispin <john@phrozen.org>
> >
> > EN7523 is an armv7 based silicon used inside broadband access type devices
> > such as xPON and xDSL. It shares various silicon blocks with MediaTek
> > silicon such as the MT7622.
>
> This is a Cortex A53 isn't it? So it's ARMv8. I thought the issue is
> that it's actually a 64bit system but you only have a 32bit
> bootloader, firmware etc?
>
> Off-topic but related:  Another MediaTek spin off, SigmaStar, seems to
> have done exactly the same thing. Cortex A53 chip running as a 32bit
> system to avoid having to fix their software. I'm interested to see if
> this makes it into arm or arm64. :)

Maybe it's best to just add them to both at the same time? The boot
loader situation might take a bit to work out, but in theory this should
be fixable.

You can generally include .dtsi files from one in the other, as you can
see from e.g. arch/arm64/boot/dts/broadcom/bcm2837-rpi-3-b.dts.

For new files, I think I would prefer having the .dts files in arm64 and
including them from arch/arm/ rather than the other way round, but
others may come up with a good reason to keep doing the reverse.
This would help encourage the thought that running a 64-bit
kernel is the better setup, rather than propagate the 32-bit kernel
nonsense on 64-bit machines.

       Arnd
Daniel Palmer Sept. 7, 2021, 12:27 p.m. UTC | #6
Hi Arnd,

On Tue, 7 Sept 2021 at 20:52, Arnd Bergmann <arnd@arndb.de> wrote:
> > Off-topic but related:  Another MediaTek spin off, SigmaStar, seems to
> > have done exactly the same thing. Cortex A53 chip running as a 32bit
> > system to avoid having to fix their software. I'm interested to see if
> > this makes it into arm or arm64. :)
>
> Maybe it's best to just add them to both at the same time? The boot
> loader situation might take a bit to work out, but in theory this should
> be fixable.

I wonder how fixable it would be..

I haven't gotten a board with the chip in question (SSD268G) yet but
from looking at some firmware binaries I can see that even u-boot is a
6 year old 32bit version.
As far as I can tell there's no PSCI, ATF etc that I think would be
expected for an arm64 machine.
I think the broken memory controller is still there so somehow I'd
need to get the heavy barrier to work in arm64. I haven't yet worked
out if that's even possible.
I think they are advertising that it supports up to 2GB of DDR. So
it's a hobbled 64bit capable system with highmem.

Putting most of the DT bits under arm64 even though it's so broken
it'll only ever boot a 32bit kernel makes sense to me.
Better than having lots of arm64 typical stuff like a newer GIC in a
file under arm and confusing everyone that comes across it.

Cheers,

Daniel
Arnd Bergmann Sept. 7, 2021, 2:11 p.m. UTC | #7
On Tue, Sep 7, 2021 at 2:27 PM Daniel Palmer <daniel@0x0f.com> wrote:
> On Tue, 7 Sept 2021 at 20:52, Arnd Bergmann <arnd@arndb.de> wrote:
> > > Off-topic but related:  Another MediaTek spin off, SigmaStar, seems to
> > > have done exactly the same thing. Cortex A53 chip running as a 32bit
> > > system to avoid having to fix their software. I'm interested to see if
> > > this makes it into arm or arm64. :)
> >
> > Maybe it's best to just add them to both at the same time? The boot
> > loader situation might take a bit to work out, but in theory this should
> > be fixable.
>
> I wonder how fixable it would be..
>
> I haven't gotten a board with the chip in question (SSD268G) yet but
> from looking at some firmware binaries I can see that even u-boot is a
> 6 year old 32bit version.
> As far as I can tell there's no PSCI, ATF etc that I think would be
> expected for an arm64 machine.

If the source code is available, creating a minimal PSCI implementation
in u-boot should be possible, and it would make it work well for both
32-bit and 64-bit kernels. There is no need for ATF here.

> I think the broken memory controller is still there so somehow I'd
> need to get the heavy barrier to work in arm64. I haven't yet worked
> out if that's even possible.

I think I missed that part of the discussion, or I forgot about it already.
What is the issue you are referring to here?

       Arnd
Daniel Palmer Sept. 7, 2021, 2:32 p.m. UTC | #8
Hi Arnd,

On Tue, 7 Sept 2021 at 23:12, Arnd Bergmann <arnd@arndb.de> wrote:

> > I think the broken memory controller is still there so somehow I'd
> > need to get the heavy barrier to work in arm64. I haven't yet worked
> > out if that's even possible.
>I think I missed that part of the discussion, or I forgot about it already.
>What is the issue you are referring to here?

Sorry. I should have put a bit more context. This is for the SSD268G
not the original target of this series. But a similar situation.
The SSD268G (according to the decompiled device tree) is the same
hardware as the MSTAR_V7 chips but with a Cortex A53 instead of the
Cortex A7.
So it probably has the same memory controller as the MSTAR_V7 stuff
and that memory controller is not coherent so it needs the kernel to
make sure memory requests are flushed out to memory before DMA
happens[0]. For arm I fixed that with the heavy mb callback. With
arm64 I have no idea how to fix that.

I'm interested to see how this Airoha EN7523 series goes as if/when I
push anything for the SSD268G it'll probably only be for a 32bit
kernel.

0 - https://elixir.bootlin.com/linux/latest/source/arch/arm/mach-mstar/mstarv7.c#L61
Arnd Bergmann Sept. 7, 2021, 3:22 p.m. UTC | #9
On Tue, Sep 7, 2021 at 4:32 PM Daniel Palmer <daniel@0x0f.com> wrote:
> On Tue, 7 Sept 2021 at 23:12, Arnd Bergmann <arnd@arndb.de> wrote:
>
> > > I think the broken memory controller is still there so somehow I'd
> > > need to get the heavy barrier to work in arm64. I haven't yet worked
> > > out if that's even possible.
> >I think I missed that part of the discussion, or I forgot about it already.
> >What is the issue you are referring to here?
>
> Sorry. I should have put a bit more context. This is for the SSD268G
> not the original target of this series. But a similar situation.
> The SSD268G (according to the decompiled device tree) is the same
> hardware as the MSTAR_V7 chips but with a Cortex A53 instead of the
> Cortex A7.
> So it probably has the same memory controller as the MSTAR_V7 stuff
> and that memory controller is not coherent so it needs the kernel to
> make sure memory requests are flushed out to memory before DMA
> happens[0]. For arm I fixed that with the heavy mb callback. With
> arm64 I have no idea how to fix that.

Ok, got it. I do remember the Mstar SoCs having this problem. My feeling
is that this should be possible to implement on arm64 as well using
an erratum fixup with a configuration option, and possibly dynamic patching
to avoid the worst effects when the workaround is built into the kernel
but not needed.

Whether this is acceptable or not is up to the arm64 architecture maintainers
of course.

       Arnd