Bjorn Andersson <bjorn.andersson@xxxxxxxxxx> writes: > On Mon 03 Sep 09:37 PDT 2018, Rakesh Pillai wrote: > >> WCN3990 is a 37-bit target but can address memory range >> only upto 35 bits. The 36th bit is used to control the >> smmu/iommu translation and the 37th bit is used by the >> internal bus masters to access the wifi subsystem internal >> SRAM. With the DMA mask set to 37i-bit, the host driver >> can get 37-bit dma address, which leads to incorrect >> address access in the target. >> >> Hence the host driver can used addresses upto 35-bit >> for WCN3990. Fix the dma mask for wcn3990 to 35-bit, >> instead of 37-bit. >> >> Tested HW: WCN3990 >> Tested FW: WLAN.HL.2.0-01188-QCAHLSWMTPLZ-1 >> >> Signed-off-by: Rakesh Pillai <pillair@xxxxxxxxxxxxxx> > > This solves the problem I'm seeing on my SDM845, where I see a > translation fault on a 32-bit address from the IOMMU, which we > previously mapped the 36 bit version of (my dma-ranges is set to 36 > bits). > > So: > > Tested-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx> Thanks for the reminder. This got piled up in my deferred queue in patchwork and I hadn't looked at it yet. I'll queue this for -next. > However, some of the changes in this patch and the fact that I get a > translation error on the lower 32 bits of the mapped iova, makes me > suspect that while the hardware is capable of 37 bits, the driver only > dealt with the lower 32. And if that's the case I would like to see > that mentioned in the commit message. Rakesh mentioned that it's actually 35 bits. Should something changed in the commit log still? I can do that if needed. -- Kalle Valo
