Re: [PATCH 0/3] Request direct mapping for modem firmware subdevice

From: Christoph Hellwig
Date: Mon Mar 16 2020 - 11:50:33 EST


On Mon, Mar 09, 2020 at 11:52:52PM +0530, Sibi Sankar wrote:
> The Q6 modem sub-system has direct access to DDR through memnoc and
> an indirect access routed through a SMMU which MSS CE (crypto engine
> sub-component of MSS) uses during out of reset sequence. Request direct
> mapping for the modem-firmware subdevice since smmu is not expected
> to provide access control/translation for these SIDs (sandboxing of the
> modem is achieved through XPUs engaged using SMC calls).

Please fix your device tree so that the device isn't bound to an
IOMMU.