Re: [PATCH v4 18/24] iommu/mediatek: Support master use iova over 32bit
From: Krzysztof Kozlowski <krzk@kernel.org>
Date: 2020-11-11 21:34:34
Also in:
linux-devicetree, linux-iommu, linux-mediatek, lkml
On Wed, Nov 11, 2020 at 08:38:32PM +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> Acked-by: Krzysztof Kozlowski <krzk@kernel.org> # memory part --- 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(-)
Acked-by: Krzysztof Kozlowski <krzk@kernel.org> Best regards, Krzysztof _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel