Re: [PATCH v2 5/7] hw/arm/digic: Map flash using memory_region_add_subregion_aliased()

[Richard Henderson]

On 4/19/21 2:43 AM, Philippe Mathieu-Daudé wrote:
> Instead of using a device specific feature for mapping the
> flash memory multiple times over a wider region, use the
> generic memory_region_add_subregion_aliased() helper.
>
> There is no change in the memory layout.
>
> * before:
>
>    $ qemu-system-arm -M canon-a1100 -S -monitor stdio
>    QEMU 5.2.90 monitor - type 'help' for more information
>    (qemu) info mtree
>    address-space: memory
>      0000000000000000-ffffffffffffffff (prio 0, i/o): system
>        0000000000000000-0000000003ffffff (prio 0, ram): ram
>        00000000c0210000-00000000c02100ff (prio 0, i/o): digic-timer
>        00000000c0210100-00000000c02101ff (prio 0, i/o): digic-timer
>        00000000c0210200-00000000c02102ff (prio 0, i/o): digic-timer
>        00000000c0800000-00000000c0800017 (prio 0, i/o): digic-uart
>        00000000f8000000-00000000ffffffff (prio 0, i/o): pflash
>          00000000f8000000-00000000f83fffff (prio 0, romd): alias pflash-alias 
> @pflash 0000000000000000-00000000003fffff
>          00000000f8400000-00000000f87fffff (prio 0, romd): alias pflash-alias 
> @pflash 0000000000000000-00000000003fffff
>          00000000f8800000-00000000f8bfffff (prio 0, romd): alias pflash-alias 
> @pflash 0000000000000000-00000000003fffff
>          ...
>          00000000ff400000-00000000ff7fffff (prio 0, romd): alias pflash-alias 
> @pflash 0000000000000000-00000000003fffff
>          00000000ff800000-00000000ffbfffff (prio 0, romd): alias pflash-alias 
> @pflash 0000000000000000-00000000003fffff
>          00000000ffc00000-00000000ffffffff (prio 0, romd): alias pflash-alias 
> @pflash 0000000000000000-00000000003fffff
>
> * after:
>
>    (qemu) info mtree
>    address-space: memory
>      0000000000000000-ffffffffffffffff (prio 0, i/o): system
>        0000000000000000-0000000003ffffff (prio 0, ram): ram
>        00000000c0210000-00000000c02100ff (prio 0, i/o): digic-timer
>        00000000c0210100-00000000c02101ff (prio 0, i/o): digic-timer
>        00000000c0210200-00000000c02102ff (prio 0, i/o): digic-timer
>        00000000c0800000-00000000c0800017 (prio 0, i/o): digic-uart
>        00000000f8000000-00000000ffffffff (prio 0, i/o): masked pflash [span of 
> 4 MiB]
>          00000000f8000000-00000000f83fffff (prio 0, romd): alias pflash [#0/32] 
> @pflash 0000000000000000-00000000003fffff
>          00000000f8400000-00000000f87fffff (prio 0, romd): alias pflash [#1/32] 
> @pflash 0000000000000000-00000000003fffff
>          00000000f8800000-00000000f8bfffff (prio 0, romd): alias pflash [#2/32] 
> @pflash 0000000000000000-00000000003fffff
>          ...
>          00000000ff400000-00000000ff7fffff (prio 0, romd): alias pflash 
> [#29/32] @pflash 0000000000000000-00000000003fffff
>          00000000ff800000-00000000ffbfffff (prio 0, romd): alias pflash 
> [#30/32] @pflash 0000000000000000-00000000003fffff
>          00000000ffc00000-00000000ffffffff (prio 0, romd): alias pflash 
> [#31/32] @pflash 0000000000000000-00000000003fffff
>
> Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> ---
>   hw/arm/digic_boards.c | 8 +++++---
>   hw/arm/Kconfig        | 1 +
>   2 files changed, 6 insertions(+), 3 deletions(-)

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

r~