On 27/08/2024 11:37, Julien Grall wrote:
Hi,
Hi Julien,
On 23/08/2024 17:31, Ayan Kumar Halder wrote:
There are features in the forthcoming patches which are dependent on
MPU. For eg fixed start address.
Also, some of the Xen features (eg STATIC_MEMORY) will be selected
by the MPU configuration.
Thus, this patch introduces a choice between MMU and MPU for the type
of memory management system. By default, MMU is selected.
All the current platforms are now made dependent on MMU.
Signed-off-by: Ayan Kumar Halder <ayan.kumar.hal...@amd.com>
---
xen/arch/arm/Kconfig | 17 ++++++++++++++++-
xen/arch/arm/platforms/Kconfig | 2 +-
2 files changed, 17 insertions(+), 2 deletions(-)
diff --git a/xen/arch/arm/Kconfig b/xen/arch/arm/Kconfig
index 323c967361..686948cefd 100644
--- a/xen/arch/arm/Kconfig
+++ b/xen/arch/arm/Kconfig
@@ -58,10 +58,25 @@ config PADDR_BITS
default 40 if ARM_PA_BITS_40
default 48 if ARM_64
+choice
+ prompt "Memory management system"
+ default MMU if ARM
+ help
+ User can choose between the different forms of memory
management system.
+ Most of the Arm based systems support MMU.
I feel this is quite subjective. So I would drop it.
Agreed.
+
config MMU
- def_bool y
+ bool "MMU"
select HAS_PMAP
select HAS_VMAP
+ help
+ Memory management unit is supported on most Arm based systems.
For this case, I would write "Select it you are plan to run Xen on
Armv7-A or Armv8-A".
Ack.
+
+config MPU
+ bool "MPU"
I think it should be gated by UNSUPPORTED. SUPPORT.md also needs to be
updated.
Ack.
+ help
+ Memory protection unit is supported on some Cortex-R systems.
Why do you make this specific to Cortex-R? Shouldn't this instead be
Armv8-R?
Yes, you are correct. It should be Armv8-R. Otherwise, someone might
think it is applicable for Cortex-R5, R7, etc.
- Ayan
