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In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: 5C25B40003 X-Stat-Signature: dk68fuuhqrd1momn66ibhqwoiepuxexm X-Rspam-User: X-HE-Tag: 1728303436-273297 X-HE-Meta: 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 dUlvN6TQ X3jIgh3EqMrNzj+uFXwx35KPMs7/+ll3raPhiQtq9hL6bZ1e+wRuVcJ6cJnVNHojZefXMNvqyYj7M3LnhkJBLayEAhpVOvHXT6L6idvrbuCE+hwaihxnA8mG+Wdn7sMiaLWcYY6eCU/47cRcAhEiRl66nK9PXQnDBiHDBHE0PRvb0G0GSbJ2M6xjzItdCepLBElx3fuT20fUjiNJPXrYOV22LpZ8qTmdbalXGYzXlX2aN0bRbL0QA/RIK8uItG5bXfMRbtwSMTgOc8sUOHO0VT/ukuh2ypiVboLAQyKtvW7sut7DM2v2LCLHJ+dGfBGAWUg6BnNGHIJKNHr64hQhmhGDJ5TMpnw+iJYPsT2kJsPeYOjMR06z6QvlMFxfJAhe4FOLlebiskqioq1XvKRu/bfs11uFhHFquB2ucSvYSwDKPv/KXTs+qxHko4r3fC7XwKcIg/Jh1HIpXhF5pnp/5NboxxAA9CXwZRkE876CseNI/oDppTM1b/8svSlIX8Bycrqt7iM6OyLj8DvP7jJa36kkOpzywfWikGIqGBhuA8xHGy37jTW+FlyrzzhcAPl8S2KkGZVLOy4uG35qsPvIUrMX8F4YnZQXv/EGIZgGfRt7CuAQ= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 06/10/2024 11:44, Vladimir Kondratiev wrote: >> I'm wondering how distro kernels will deal with that since some >> platforms will need the ZONE_DMA32 and some others will break when >> enabled as you have shown. > > I agree platforms with no ZONE_DMA32 is non-portable, > to address this I will add dependency on NONPORTABLE and re-submit > shortly. Thanks for pointing that. So the last time I got to looking at this, the SoC had no memory in the 32bit space and all the on-chip IP blocks where all 64bit DMA capable. The only thing we didn't sort out was anything connected by the DW PCIe core, but we think that could use an inbound translation window. However, software wise we didn't have the time to try and either hack something into the kernel or write some form of IOMMU for the inbound translation unit. We just removed the warnings to get the initial testing through. >> Is there a way to make it optional at runtime instead? > Unfortunately no, or at least I see no way to do so > > Thanks, Vladimir > _______________________________________________ > linux-riscv mailing list > linux-riscv@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-riscv > -- Ben Dooks http://www.codethink.co.uk/ Senior Engineer Codethink - Providing Genius https://www.codethink.co.uk/privacy.html