[PATCH] Revert "lmb: Reinstate access to memory above ram_top"

[Marek Vasut]

On 5/30/26 3:43 PM, Peter Robinson wrote:
> On Sat, 30 May 2026 at 14:27, Marek Vasut <marek.vasut at mailbox.org> wrote:
>>
>> On 5/29/26 6:29 PM, Peter Robinson wrote:
>>> This reverts commit a3075db94d49f415658bf7e961e1eae90d9abc33.
>>>
>>> This causes boot issues on Raspberry Pi 4/5 in a number of ways,
>>> the mmc needs memory < 4Gb, the mailbox needs it < 1Gb at the
>>> very least so there's some work to be done here for that platform.
>>>
>>> Signed-off-by: Peter Robinson <pbrobinson at gmail.com>
>> NAK
>>
>> The revert is wrong as that breaks other things, like use of DRAM above
>> 4 GiB boundary, which is exactly why the original change was implemented.
> 
> Read the thread, Tom asked me to send a revert.

The revert is wrong, I already sent you a way to fix your RPi problem 
too. It would be nice if you didn't use "Tom said so" as an argument in 
technical discussion, that is not helpful.

>> If RPi has limitations, then those limitations should be imposed on RPi,
>> not globally. Please add the LMB reservations on RPi only. Use
>> lmb_arch_add_memory() to add those restrictions per-board/soc/arch instead.