Re: [PATCH v4 2/2] remoteproc: add AMD BRAM-based remote processor driver

[Michal Simek <michal.simek@amd.com>]

On 7/3/26 18:39, Mathieu Poirier wrote:
> Hi Ben,
> 
> On Mon, Jun 29, 2026 at 09:40:03AM -0700, Ben Levinsky wrote:
>> Add a remoteproc driver for AMD soft-core processor subsystems
>> instantiated in programmable logic and using dual-port BRAM for
>> firmware storage and execution.
>>
>> The driver parses the firmware memory window from the remoteproc device
>> node's reg property, interprets that address and size in the
>> processor-local address space, and then uses standard devicetree
>> address translation through the parent bus ranges property to obtain
>> the corresponding Linux-visible system physical address.
>>
>> The resulting translated region is registered as the executable
>> remoteproc carveout and coredump segment.
>>
>> The processor is controlled through an active-low reset GPIO and a
>> subsystem clock. The clock is enabled before reset is released, and the
>> processor is kept in reset until firmware loading completes.
>>
>> The firmware-name property is optional, allowing firmware to be
>> assigned later through the remoteproc framework. Firmware images
>> without a resource table are also accepted.
>>
>> Signed-off-by: Ben Levinsky <ben.levinsky@amd.com>
>> ---
>>   drivers/remoteproc/Kconfig          |  11 ++
>>   drivers/remoteproc/Makefile         |   1 +
>>   drivers/remoteproc/amd_bram_rproc.c | 213 ++++++++++++++++++++++++++++
>>   3 files changed, 225 insertions(+)
>>   create mode 100644 drivers/remoteproc/amd_bram_rproc.c
>>
>> diff --git a/drivers/remoteproc/Kconfig b/drivers/remoteproc/Kconfig
>> index c521c744e7db..58fa566b609f 100644
>> --- a/drivers/remoteproc/Kconfig
>> +++ b/drivers/remoteproc/Kconfig
>> @@ -23,6 +23,17 @@ config REMOTEPROC_CDEV
>>   
>>   	  It's safe to say N if you don't want to use this interface.
>>   
>> +config AMD_BRAM_REMOTEPROC
>> +	tristate "AMD BRAM-based remoteproc support"
>> +	depends on OF && COMMON_CLK && (GPIOLIB || COMPILE_TEST)
>> +	help
>> +	  Say y or m here to support a BRAM-based remote processor managed
>> +	  through the remoteproc framework.
>> +
>> +	  The processor is controlled through a reset GPIO and clock.
>> +
> 
> This last sentence doesn't belong here - please remove.
> 
> Looking at the bindings and this Kconfig I wonder why the emphasis of the naming
> convention, i.e "BRAM-based remoteproc" is placed on the kind of memory the
> remote processor is connected to rather than the remote processor itself.
> 
> Wouldn't it be better to have something like "AMD MicroBlaze/V remote
> processor"?  What happens when we get another AMD softcore that is completely
> different than MicroBlaze/V that is also connected to the same type of memory?
> 
> I'm good with the implemenation, I just wonder about the name...

We started with very generic amd,bram-proc compatible string and then based on 
discussion
https://lore.kernel.org/all/20260427162703.1644103-2-ben.levinsky@amd.com/
we got recommendation to treat is as soc specific instead of generic.
Which give us back to origin point if driver should be more soc specific or not.

I think no issue with AMD prefix.

BRAM - that's technology used for access. And I see value in symbol to state it 
because access to different memory can be done differently too.

Shouldn't be there any soc string? This is for zynqmp, versal* SOCs that's why 
hard to choose which one.

The driver is written in very generic way that if there is arm, mips, ppc, 
different risc-v or others access will be the same. Our primary target is 
obviously MicroBlaze/V and I don't think it is a problem to change description 
to just reference them even it is technically possible to connect different cpus 
too.

Is this enough?

-	tristate "AMD BRAM-based remoteproc support"
+	tristate "AMD MicroBlaze/V BRAM-based remoteproc support"

Are you fine with AMD_BRAM_REMOTEPROC symbol name?

Thanks,
Michal