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iommu: sun50i: clear bypass register

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[ Upstream commit 927c70c93d929f4c2dcaf72f51b31bb7d118a51a ]

The Allwinner H6 IOMMU has a bypass register, which allows to circumvent
the page tables for each possible master. The reset value for this
register is 0, which disables the bypass.
The Allwinner H616 IOMMU resets this register to 0x7f, which activates
the bypass for all masters, which is not what we want.

Always clear this register to 0, to enforce the usage of page tables,
and make this driver compatible with the H616 in this respect.

Signed-off-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Chen-Yu Tsai <wens@csie.org>
Link: https://lore.kernel.org/r/20240616224056.29159-2-andre.przywara@arm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Jernej Skrabec 2024-06-16 23:40:52 +01:00 committed by Ksawlii
parent 7d62680ff2
commit b20eddd632
1 changed files with 1 additions and 0 deletions
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drivers/iommu/sun50i-iommu.c
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@ -380,6 +380,7 @@ static int sun50i_iommu_enable(struct sun50i_iommu *iommu)
IOMMU_TLB_PREFETCH_MASTER_ENABLE(3) |
IOMMU_TLB_PREFETCH_MASTER_ENABLE(4) |
IOMMU_TLB_PREFETCH_MASTER_ENABLE(5));
iommu_write(iommu, IOMMU_BYPASS_REG, 0);
iommu_write(iommu, IOMMU_INT_ENABLE_REG, IOMMU_INT_MASK);
iommu_write(iommu, IOMMU_DM_AUT_CTRL_REG(SUN50I_IOMMU_ACI_NONE),
IOMMU_DM_AUT_CTRL_RD_UNAVAIL(SUN50I_IOMMU_ACI_NONE, 0) |