Re: [RFC PATCH-for-6.1 00/10] hw/misc: Add memory_region_add_subregion_aliased() helper
On 26/03/2021 00:27, Philippe Mathieu-Daudé wrote:
Hi,
This series introduce the memory_region_add_subregion_aliased()
helper which basically create a device which maps a subregion
multiple times.
Examples are easier, so having a subregion aliased every @span_size
then mapped onto a container at an offset, you get something like:
^---^
| |
| |
| +---+ | +-+ <--+
| | +-+ |
| | | | |
| | +---> | alias#3 | |
| | | | | |
| | | +-+ |
| | | +-+ |
| | | | | |
| | | +---> | alias#2 | |
| | | | | | |region
| container | | | +-+ | size
| | | | +-+ |
| | | | | | |
| | | | +> | alias#1 | |
| | | | | | | |
| | | | | +-+ <--+ |
| | +-+---+--+--+ +-+ | |
| | | | | | |span |
| | | subregion +-> | alias#0 | |size |
offset | | | | | | | |
+> | +---+ | +---+ +-+ <--+<--+
| | |
| | |
| | |
| | |
| | |
| ^---^
I know it need more documentation and tests, but I prefer to send
as draft RFC for early review before spending more time on it.
Based-on: <20210325120921.858993-1-f4...@amsat.org>
https://www.mail-archive.com/qemu-devel@nongnu.org/msg795218.html
Philippe Mathieu-Daudé (10):
hw/misc: Add device to help managing aliased memory regions
hw/arm/musicpal: Open-code pflash_cfi02_register() call
hw/arm/musicpal: Map flash using memory_region_add_subregion_aliased()
hw/arm/digic: Open-code pflash_cfi02_register() call
hw/arm/digic: Map flash using memory_region_add_subregion_aliased()
hw/block/pflash_cfi02: Remove pflash_setup_mappings()
hw/block/pflash_cfi02: Simplify pflash_cfi02_register() prototype
hw/misc/aliased_region: Simplify aliased I/O regions
hw/m68k/q800: Add MacIO container
hw/m68k/q800: Map MacIO using memory_region_add_subregion_aliased()
include/hw/block/flash.h | 1 -
include/hw/misc/aliased_region.h | 91 +++
hw/arm/digic_boards.c| 28 -
hw/arm/musicpal.c| 29 -
hw/arm/xilinx_zynq.c | 2 +-
hw/block/pflash_cfi02.c | 36 +-
hw/lm32/lm32_boards.c| 4 +-
hw/m68k/q800.c | 61 +-
hw/misc/aliased_region.c | 185 +++
hw/ppc/ppc405_boards.c | 6 +-
hw/sh4/r2d.c | 2 +-
MAINTAINERS | 6 +
hw/arm/Kconfig | 2 +
hw/m68k/Kconfig | 1 +
hw/misc/Kconfig | 3 +
hw/misc/meson.build | 1 +
16 files changed, 375 insertions(+), 83 deletions(-)
create mode 100644 include/hw/misc/aliased_region.h
create mode 100644 hw/misc/aliased_region.c
Now this is interesting. Are there any limits to the number of aliased memory regions
supported? In my q800 dev branch I have the following commit:
https://github.com/mcayland/qemu/commit/272547abbca69906dab5d94af32c5117691a1050
("q800: reimplement mac-io region aliasing using IO memory region") to implement
similar functionality because adding just one more device into the aliased region is
enough to cause QEMU to assert with "phys_section_add: Assertion `map->sections_nb <
TARGET_PAGE_SIZE'
failed" on startup.
ATB,
Mark.
Re: [RFC PATCH-for-6.1 00/10] hw/misc: Add memory_region_add_subregion_aliased() helper
On 3/25/21 6:27 PM, Philippe Mathieu-Daudé wrote: This series introduce the memory_region_add_subregion_aliased() helper which basically create a device which maps a subregion multiple times. I must say, the example mtree changes are persuasive. I'll look in more detail later. r~
[RFC PATCH-for-6.1 00/10] hw/misc: Add memory_region_add_subregion_aliased() helper
Hi, This series introduce the memory_region_add_subregion_aliased() helper which basically create a device which maps a subregion multiple times. Examples are easier, so having a subregion aliased every @span_size then mapped onto a container at an offset, you get something like: ^---^ | | | | | +---+ | +-+ <--+ | | +-+ | | | | | | | | +---> | alias#3 | | | | | | | | | | | +-+ | | | | +-+ | | | | | | | | | | +---> | alias#2 | | | | | | | | |region | container | | | +-+ | size | | | | +-+ | | | | | | | | | | | | +> | alias#1 | | | | | | | | | | | | | | | +-+ <--+ | | | +-+---+--+--+ +-+ | | | | | | | | |span | | | | subregion +-> | alias#0 | |size | offset | | | | | | | | +> | +---+ | +---+ +-+ <--+<--+ | | | | | | | | | | | | | | | | ^---^ I know it need more documentation and tests, but I prefer to send as draft RFC for early review before spending more time on it. Based-on: <20210325120921.858993-1-f4...@amsat.org> https://www.mail-archive.com/qemu-devel@nongnu.org/msg795218.html Philippe Mathieu-Daudé (10): hw/misc: Add device to help managing aliased memory regions hw/arm/musicpal: Open-code pflash_cfi02_register() call hw/arm/musicpal: Map flash using memory_region_add_subregion_aliased() hw/arm/digic: Open-code pflash_cfi02_register() call hw/arm/digic: Map flash using memory_region_add_subregion_aliased() hw/block/pflash_cfi02: Remove pflash_setup_mappings() hw/block/pflash_cfi02: Simplify pflash_cfi02_register() prototype hw/misc/aliased_region: Simplify aliased I/O regions hw/m68k/q800: Add MacIO container hw/m68k/q800: Map MacIO using memory_region_add_subregion_aliased() include/hw/block/flash.h | 1 - include/hw/misc/aliased_region.h | 91 +++ hw/arm/digic_boards.c| 28 - hw/arm/musicpal.c| 29 - hw/arm/xilinx_zynq.c | 2 +- hw/block/pflash_cfi02.c | 36 +- hw/lm32/lm32_boards.c| 4 +- hw/m68k/q800.c | 61 +- hw/misc/aliased_region.c | 185 +++ hw/ppc/ppc405_boards.c | 6 +- hw/sh4/r2d.c | 2 +- MAINTAINERS | 6 + hw/arm/Kconfig | 2 + hw/m68k/Kconfig | 1 + hw/misc/Kconfig | 3 + hw/misc/meson.build | 1 + 16 files changed, 375 insertions(+), 83 deletions(-) create mode 100644 include/hw/misc/aliased_region.h create mode 100644 hw/misc/aliased_region.c -- 2.26.2
