Re: [Qemu-devel] [Qemu-arm] [PATCH 0/8] arm/raspi: Make fb handle virtual viewport

[Peter Maydell]

Ping for code review?

thanks
-- PMM

On 14 August 2018 at 15:44, Peter Maydell <address@hidden> wrote:
> The raspi framebuffer supports a virtual viewport which can
> be set up so that the virtual framebuffer size is larger than
> the physical screen size, and the displayed area is at some
> offset within this virtual framebuffer area. This patchset
> implements that support.
>
> To do that I had to do a fair amount of refactoring, because
> getting the viewport code to work correctly and prevent the
> guest from making it fall over by specifying silly offsets
> or sizes requires that we properly validate and clip the
> config that the guest sends us.
>
> Note that the documentation in places like
> https://github.com/raspberrypi/firmware/wiki/Mailbox-property-interface
> has various errors in it. The behaviour implemented here
> corresponds to how a hardware raspi2 I tested seems to behave,
> using test programs based on the code from
> http://www.valvers.com/open-software/raspberry-pi/step05-bare-metal-programming-in-c-pt5/
>
> (I was a little bit hampered because I couldn't get the rpi
> to actually *display* anything to the HDMI port, so mostly
> I was testing the edge case behaviour of attempting to set
> and read back various config values.)
>
> This series fixes this bug:
> https://bugs.launchpad.net/qemu/+bug/1777672
>
> thanks
> -- PMM
>
> Peter Maydell (8):
>   hw/misc/bcm2835_fb: Move config fields to their own struct
>   hw/misc/bcm2835_property: Track fb settings using BCM2835FBConfig
>   hw/display/bcm2835_fb: Drop unused size and pitch fields
>   hw/display/bcm2835_fb: Reset resolution, etc correctly
>   hw/display/bcm2835_fb: Abstract out calculation of pitch, size
>   hw/display/bcm2835_fb: Fix handling of virtual framebuffer
>   hw/display/bcm2835_fb: Validate config settings
>   hw/display/bcm2835_fb: Validate bcm2835_fb_mbox_push() config
>
>  include/hw/display/bcm2835_fb.h |  59 +++++++--
>  hw/display/bcm2835_fb.c         | 218 +++++++++++++++++++-------------
>  hw/misc/bcm2835_property.c      | 123 +++++++++---------
>  3 files changed, 240 insertions(+), 160 deletions(-)