| Message ID | 20221029224307.138822-1-gshan@redhat.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | hw/arm/virt: Improve address assignment for high memory regions | expand |
On Sat, 29 Oct 2022 at 23:43, Gavin Shan <gshan@redhat.com> wrote: > > There are three high memory regions, which are VIRT_HIGH_REDIST2, > VIRT_HIGH_PCIE_ECAM and VIRT_HIGH_PCIE_MMIO. Their base addresses > are floating on highest RAM address. However, they can be disabled > in several cases. > > (1) One specific high memory region is disabled by developer by > toggling vms->highmem_{redists, ecam, mmio}. > > (2) VIRT_HIGH_PCIE_ECAM region is disabled on machine, which is > 'virt-2.12' or ealier than it. > > (3) VIRT_HIGH_PCIE_ECAM region is disabled when firmware is loaded > on 32-bits system. > > (4) One specific high memory region is disabled when it breaks the > PA space limit. > > The current implementation of virt_set_memmap() isn't comprehensive > because the space for one specific high memory region is always > reserved from the PA space for case (1), (2) and (3). In the code, > 'base' and 'vms->highest_gpa' are always increased for those three > cases. It's unnecessary since the assigned space of the disabled > high memory region won't be used afterwards. > > The series intends to improve the address assignment for these > high memory regions and introduces new properties for user to > selectively disable those 3 high memory regions. I've applied this patchset to a target-arm-for-8.0 branch that will end up being the target-arm queue once 7.2 is out. thanks -- PMM
There are three high memory regions, which are VIRT_HIGH_REDIST2, VIRT_HIGH_PCIE_ECAM and VIRT_HIGH_PCIE_MMIO. Their base addresses are floating on highest RAM address. However, they can be disabled in several cases. (1) One specific high memory region is disabled by developer by toggling vms->highmem_{redists, ecam, mmio}. (2) VIRT_HIGH_PCIE_ECAM region is disabled on machine, which is 'virt-2.12' or ealier than it. (3) VIRT_HIGH_PCIE_ECAM region is disabled when firmware is loaded on 32-bits system. (4) One specific high memory region is disabled when it breaks the PA space limit. The current implementation of virt_set_memmap() isn't comprehensive because the space for one specific high memory region is always reserved from the PA space for case (1), (2) and (3). In the code, 'base' and 'vms->highest_gpa' are always increased for those three cases. It's unnecessary since the assigned space of the disabled high memory region won't be used afterwards. The series intends to improve the address assignment for these high memory regions and introduces new properties for user to selectively disable those 3 high memory regions. PATCH[1-4] preparatory work for the improvment PATCH[5] improve high memory region address assignment PATCH[6] adds 'compact-highmem' to enable or disable the optimization PATCH[7] adds properties so that high memory regions can be disabled v6: https://lists.nongnu.org/archive/html/qemu-arm/2022-10/msg00490.html v5: https://lists.nongnu.org/archive/html/qemu-arm/2022-10/msg00280.html v4: https://lists.nongnu.org/archive/html/qemu-arm/2022-10/msg00067.html v3: https://lists.nongnu.org/archive/html/qemu-arm/2022-09/msg00258.html v2: https://lore.kernel.org/all/20220815062958.100366-1-gshan@redhat.com/T/ v1: https://lists.nongnu.org/archive/html/qemu-arm/2022-08/msg00013.html Changelog ========== v7: * Pick review-by from Connie/Eric/Marc (Connie/Eric/Marc) * Use 'base - 1' to update 'vms->highest_gpa' in PATCH[v7 5] (Eric) * Replace 'even' with 'even if' in the comments about the legacy and compact layout in PATCH[v7 6] (Connie) * The maximal supported CPUs are calculated based on property 'highmem-redists' and the improved comments and error messages for this property (Connie) v6: * Pick review-by from Connie/Eric (Connie/Eric) * Make the changes obvious in PATCH[v6 5/7] (Eric) * Move the example to commit log and describe the legacy and compact layout in code's comments in PATCH[v6 6/7] (Eric) * Comment and commit message improvements (Connie/Eric) * Add 3 properties in PATCH[v6 7/7], allowing user to disable those 3 high memory regions (Marc) v5: * Pick review-by and tested-by (Connie/Zhenyu) * Add extra check in PATCH[v5 4/6] (Connie) * Improve comments about compatibility for disabled regions in PATCH[v5 5/6] (Connie) v4: * Add virt_get_high_memmap_enabled() helper (Eric) * Move 'vms->highmem_compact' and related logic from PATCH[v4 6/6] to PATCH[v4 5/6] to avoid git-bisect breakage (Eric) * Document the legacy and optimized high memory region layout in commit log and source code (Eric) v3: * Reorder the patches (Gavin) * Add 'highmem-compact' property for backwards compatibility (Eric) v2: * Split the patches for easier review (Gavin) * Improved changelog (Marc) * Use 'bool fits' in virt_set_high_memmap() (Eric) Gavin Shan (7): hw/arm/virt: Introduce virt_set_high_memmap() helper hw/arm/virt: Rename variable size to region_size in virt_set_high_memmap() hw/arm/virt: Introduce variable region_base in virt_set_high_memmap() hw/arm/virt: Introduce virt_get_high_memmap_enabled() helper hw/arm/virt: Improve high memory region address assignment hw/arm/virt: Add 'compact-highmem' property hw/arm/virt: Add properties to disable high memory regions docs/system/arm/virt.rst | 17 ++++ hw/arm/virt.c | 193 ++++++++++++++++++++++++++++++++------- include/hw/arm/virt.h | 2 + 3 files changed, 177 insertions(+), 35 deletions(-)