Re: [PATCH] ACPI/IORT: Make dma masks set-up IORT specific

From: Hanjun Guo
Date: Tue Dec 06 2016 - 03:14:31 EST


On 2016/12/5 20:26, Lorenzo Pieralisi wrote:
> The introduction of acpi_dma_configure() allows to configure DMA
> and related IOMMU for any device that is DMA capable. To achieve
> that goal it ensures DMA masks are set-up to sane default values
> before proceeding with IOMMU and DMA ops configuration.
>
> On x86/ia64 systems, through acpi_bind_one(), acpi_dma_configure() is
> called for every device that has an ACPI companion, in that every device
> is considered DMA capable on x86/ia64 systems (ie acpi_get_dma_attr() API),
> which has the side effect of initializing dma masks also for
> pseudo-devices (eg CPUs and memory nodes) and potentially for devices
> whose dma masks were not set-up before the acpi_dma_configure() API was
> introduced, which may have noxious side effects.
>
> Therefore, in preparation for IORT firmware specific DMA masks set-up,
> wrap the default DMA masks set-up in acpi_dma_configure() inside an IORT
> specific wrapper that reverts to a NOP on x86/ia64 systems, restoring the
> default expected behaviour on x86/ia64 systems and keeping DMA default
> masks set-up on IORT based (ie ARM) arch configurations.
>
> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx>
> Cc: Will Deacon <will.deacon@xxxxxxx>
> Cc: Hanjun Guo <hanjun.guo@xxxxxxxxxx>

Add this patch on top of your v9 acpi smmu patchset,
tested on Hisilicon D03 (ARM64), devices with SMMU
enabled work fine,

Tested-by: Hanjun Guo <hanjun.guo@xxxxxxxxxx>
Reviewed-by: Hanjun Guo <hanjun.guo@xxxxxxxxxx>

Thanks
Hanjun