On Thu, 2021-09-30 at 13:26 +0200, Dafna Hirschfeld wrote: > > On 13.08.21 08:53, Yong Wu wrote: > > Prepare for 2 HWs that sharing pgtable in different power-domains. > > > > The previous SoC don't have PM. Only mt8192 has power-domain, > > and it is display's power-domain which nearly always is enabled. > > hi, I see that in mt1873.dtsi, many devices that uses the iommu have > the > 'power-domains' property. Sorry, I didn't clarify this clear. I mean the iommu device don't have this property rather than the other device. > > > > > When there are 2 M4U HWs, it may has problem. > > In this function, we get the pm_status via the m4u dev, but it > > don't > > reflect the real power-domain status of the HW since there may be > > other > > HW also use that power-domain. > > > > Currently we could not get the real power-domain status, thus > > always > > pm_runtime_get here. > > > > Prepare for mt8195, thus, no need fix tags here. > > > > This patch may drop the performance, we expect the user could > > pm_runtime_get_sync before dma_alloc_attrs which need tlb ops. > > > > Could you explain this sentence a bit? should the user call > pm_runtime_get_sync > before calling dma_alloc_attrs? In v3, I have removed this patch. Use [1] instead. [1] https://lore.kernel.org/linux-mediatek/20210923115840.17813-13-yong.wu@xxxxxxxxxxxx/ Thanks. > > Thanks, > Dafna > > > Signed-off-by: Yong Wu <yong.wu@xxxxxxxxxxxx> > > --- > > drivers/iommu/mtk_iommu.c | 5 ++++- > > 1 file changed, 4 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c > > index add23a36a5e2..abc721a1da21 100644 > > --- a/drivers/iommu/mtk_iommu.c > > +++ b/drivers/iommu/mtk_iommu.c > > @@ -238,8 +238,11 @@ static void > > mtk_iommu_tlb_flush_range_sync(unsigned long iova, size_t size, > > > > for_each_m4u(data, head) { > > if (has_pm) { > > - if (pm_runtime_get_if_in_use(data->dev) <= 0) > > + ret = pm_runtime_resume_and_get(data->dev); > > + if (ret < 0) { > > + dev_err(data->dev, "tlb flush: pm get > > fail %d.\n", ret); > > continue; > > + } > > } > > > > spin_lock_irqsave(&data->tlb_lock, flags); > >
