[PATCH v1] lmb: Optionally limit available memory to 4 GiB on limited systems

[Marek Vasut]

On 6/4/26 8:43 AM, Ilias Apalodimas wrote:
> On Wed, 3 Jun 2026 at 17:18, Marek Vasut
> <marek.vasut+renesas at mailbox.org> wrote:
>>
>> Some architectures can not DMA above 4 GiB boundary,
>> limit available memory to memory below 4 GiB boundary.
>>
>> Signed-off-by: Marek Vasut <marek.vasut+renesas at mailbox.org>
>> ---
>> Cc: Andrew Goodbody <andrew.goodbody at linaro.org>
>> Cc: David Lechner <dlechner at baylibre.com>
>> Cc: Heiko Schocher <hs at nabladev.com>
>> Cc: Heinrich Schuchardt <xypron.glpk at gmx.de>
>> Cc: Holger Brunck <holger.brunck at hitachienergy.com>
>> Cc: Ilias Apalodimas <ilias.apalodimas at linaro.org>
>> Cc: Peter Robinson <pbrobinson at gmail.com>
>> Cc: Quentin Schulz <quentin.schulz at cherry.de>
>> Cc: Simon Glass <sjg at chromium.org>
>> Cc: Sughosh Ganu <sughosh.ganu at arm.com>
>> Cc: Tom Rini <trini at konsulko.com>
>> Cc: u-boot at lists.denx.de
>> ---
>> V1: Invert the IS_ENABLED(CONFIG_LMB_LIMIT_DMA_BELOW_4G) conditional
>> ---
> 
> Reviewed-by: Ilias Apalodimas <ilias.apalodimas at linaro.org>
> Tested-by: Ilias Apalodimas <ilias.apalodimas at linaro.org> #rpi4 8GiB
I sent a follow up patch for the Kconfig option name too.