iommu/ipmmu-vmsa: Drop LPAE Kconfig dependency
PATCH 1/1 iommu/ipmmu-vmsa: Drop LPAE Kconfig dependency
From: Magnus Damm <[email protected]>
Neither the ARM page table code enabled by IOMMU_IO_PGTABLE_LPAE nor the IPMMU_VMSA driver actually depends on ARM_LPAE, so get rid of the dependency.
Tested with ipmmu-vmsa on r8a7794 ALT and a kernel config using:
# CONFIG_ARM_LPAE is not set
---
drivers/iommu/Kconfig | 1 - 1 file changed, 1 deletion(-)
drivers/iommu/Kconfig +0 -1
@@ -324,7 +324,6 @@ config SHMOBILE_IOMMU_L1SIZE config IPMMU_VMSA bool "Renesas VMSA-compatible IPMMU" - depends on ARM_LPAE depends on ARCH_SHMOBILE || COMPILE_TEST select IOMMU_API select IOMMU_IO_PGTABLE_LPAE
Hi Magnus,
Thank you for the patch.
Quoted 8 lines · On Monday 19 October 2015 12:02:53 Magnus Damm wrote:
From: Magnus Damm <[email protected]>
Neither the ARM page table code enabled by
IOMMU_IO_PGTABLE_LPAEnor theIPMMU_VMSAdriver actually depends onARM_LPAE, so get rid of the dependency.Tested with ipmmu-vmsa on r8a7794 ALT and a kernel config using:
#CONFIG_ARM_LPAEis not set
The driver only supports the 40-bits page table format for now, hence the dependency on LPAE, but it indeed seems that the dependency is bogus. As long as the 8 MSBs of the translated address are all 0 I assume the output 40-bit address is usable on a 32-bit physical address system.
How have you tested the patch ?
Quoted 16 lines
Signed-off-by Magnus Damm <[email protected]>---
drivers/iommu/Kconfig | 1 - 1 file changed, 1 deletion(-)drivers/iommu/Kconfig +0
-1@@ -324,7 +324,6 @@ config SHMOBILE_IOMMU_L1SIZE config IPMMU_VMSA bool "Renesas VMSA-compatible IPMMU" - depends on ARM_LPAE depends on ARCH_SHMOBILE || COMPILE_TEST select IOMMU_API select IOMMU_IO_PGTABLE_LPAE
Signature · 3 lines
Regards, Laurent Pinchart
Hi Laurent,
Quoted 14 lines · Laurent Pinchart
Hi Magnus,
Thank you for the patch.
Quoted 8 lines · On Monday 19 October 2015 12:02:53 Magnus Damm wrote:
From: Magnus Damm <[email protected]>
Neither the ARM page table code enabled by
IOMMU_IO_PGTABLE_LPAEnor theIPMMU_VMSAdriver actually depends onARM_LPAE, so get rid of the dependency.Tested with ipmmu-vmsa on r8a7794 ALT and a kernel config using:
#CONFIG_ARM_LPAEis not set
Quoted 6 lines
The driver only supports the 40-bits page table format for now, hence the dependency on LPAE, but it indeed seems that the dependency is bogus. As long as the 8 MSBs of the translated address are all 0 I assume the output 40-bit address is usable on a 32-bit physical address system.
How have you tested the patch ?
Modetest with local IPMMUMX enablement on r8a7794 ALT.
Cheers,
/ magnus
Laurent Pinchart
Acked-byHi Magnus,
Quoted 11 lines · On Tuesday 20 October 2015 17:54:59 Magnus Damm wrote:
Quoted 10 lines · Laurent Pinchart
Quoted 8 lines · On Monday 19 October 2015 12:02:53 Magnus Damm wrote:
From: Magnus Damm <[email protected]>
Neither the ARM page table code enabled by
IOMMU_IO_PGTABLE_LPAEnor theIPMMU_VMSAdriver actually depends onARM_LPAE, so get rid of the dependency.Tested with ipmmu-vmsa on r8a7794 ALT and a kernel config using:
#CONFIG_ARM_LPAEis not set
Quoted 8 lines
Quoted 6 lines
The driver only supports the 40-bits page table format for now, hence the dependency on LPAE, but it indeed seems that the dependency is bogus. As long as the 8 MSBs of the translated address are all 0 I assume the output 40-bit address is usable on a 32-bit physical address system.
How have you tested the patch ?
Modetest with local IPMMUMX enablement on r8a7794 ALT.
Then,
Signature · 3 lines
Regards, Laurent Pinchart
Quoted 10 lines · Magnus Damm
From: Magnus Damm <[email protected]>
Neither the ARM page table code enabled by
IOMMU_IO_PGTABLE_LPAEnor theIPMMU_VMSAdriver actually depends onARM_LPAE, so get rid of the dependency.Tested with ipmmu-vmsa on r8a7794 ALT and a kernel config using:
#CONFIG_ARM_LPAEis not setSigned-off-by Magnus Damm <[email protected]>
Applied, thanks.