Re: [PATCH v3 18/24] iommu/mediatek: Support master use iova over 32bit

Krzysztof Kozlowski
2020-10-06T07:18:55Z

On Wed, Sep 30, 2020 at 03:06:41PM +0800, Yong Wu wrote:
> After extending v7s, our pagetable already support iova reach
> 16GB(34bit). the master got the iova via dma_alloc_attrs may reach
> 34bits, but its HW register still is 32bit. then how to set the
> bit32/bit33 iova? this depend on a SMI larb setting(bank_sel).
>
> we separate whole 16GB iova to four banks:
> bank: 0: 0~4G; 1: 4~8G; 2: 8-12G; 3: 12-16G;
> The bank number is (iova >> 32).
>
> We will preassign which bank the larbs belong to. currently we don't
> have a interface for master to adjust its bank number.
>
> Each a bank is a iova_region which is a independent iommu-domain.
> the iova range for each iommu-domain can't cross 4G.
>
> Signed-off-by: Yong Wu <yong.wu@mediatek.com>
> ---
> drivers/iommu/mtk_iommu.c | 12 +++++++++---
> drivers/memory/mtk-smi.c | 7 +++++++
> include/soc/mediatek/smi.h | 1 +
> 3 files changed, 17 insertions(+), 3 deletions(-)

For the memory part:
Acked-by: Krzysztof Kozlowski <krzk@kernel.org>

Best regards,
Krzysztof