On Wed, Oct 01 2014 at 01:27:27 AM, Arnd Bergmann wrote:
> On Tuesday 30 September 2014 18:28:13 Mitchel Humpherys wrote:
>> + if (readl_poll_timeout_atomic(cb_base + ARM_SMMU_CB_ATSR, tmp,
>> + !(tmp & ATSR_ACTIVE), 50, 100)) {
>>
>
> This looks really bad.
>
On Tuesday 30 September 2014 18:28:13 Mitchel Humpherys wrote:
> + if (readl_poll_timeout_atomic(cb_base + ARM_SMMU_CB_ATSR, tmp,
> + !(tmp & ATSR_ACTIVE), 50, 100)) {
>
This looks really bad.
You are doing up to 50 100us delays, each of which can be much long
Currently, we provide the iommu_ops.iova_to_phys service by doing a
table walk in software to translate IO virtual addresses to physical
addresses. On SMMUs that support it, it can be useful to ask the SMMU
itself to do the translation. This can be used to warm the TLBs for an
SMMU. It can also be
