[OpenPower-Firmware] [RFC] Drop untested graphic support from the build

[Stewart Smith]

Paul Menzel <pmenzel+openpower-firmware at molgen.mpg.de> writes:

> Dear Stewart,
>
>
> Am 22.08.2018 um 06:51 schrieb Stewart Smith:
>> Paul Menzel <pmenzel+openpower-firmware at molgen.mpg.de> writes:
>>> On 08/21/18 06:53, Stewart Smith wrote:
>>>> Paul Menzel <pmenzel+openpower-firmware at molgen.mpg.de> writes:
>>>>> On 08/20/18 08:54, Joel Stanley wrote:
>>>>>> Back in the day Tuletta (P8) machines would use Radeon GPU drivers. No
>>>>>> one has tested this in many moons. To save all systems are paying for
>>>>>> the kernel driver,
>>>>>
>>>>> I do not understand the sentence.
>>>>
>>>> Tuleta is the name for the S812L, S822L etc servers that IBM released as
>>>> the first POWER8 systems. Allegedly you can purchase these with some
>>>> really old Radeon card, although we've never had one in the LTC to be
>>>> able to check if graphics come out.
>>>
>>> Thank you for the explanation, but I only meant the last version.
>>>
>>>> To save all systems are paying for the kernel driver,
>>>
>>> A verb seems to have snucked in. But What is paid? The image size?
>> 
>> Yeah, image size and boot time.
>
> It’d be great to have specific numbers (for (at least) one test system) 
> in the commit message.
>
>> We don't really get multiple megabytes per second loading off flash, and
>> the bootkernel image is close to 16mb. Additionally, the initramfs takes
>> about 2.5 seconds to decompress.
>
> If the image is smaller now, and decompression takes so long, it might 
> be worth to test if LZ4 gives better timings by having a larger image 
> size but faster decompression.

The problem is that flash chips in existing machines are a fixed size :)

We do have spare space on several system types though, and we could use
our existing space more efficiently, but I'd prefer us attack that as a
separate problem.

> Additionally, I always wondered, why the initrd (if no encryption is 
> used) can’t be loaded from a hard disk (preferably SSD) or a fast
> network.

This is the initramfs for petitboot, so without it, you have no way to
configure where to find it from. i.e. if diskless node there'd be no way
to say it should load off the network rather than local disk.

-- 
Stewart Smith
OPAL Architect, IBM.