Messages in this thread | | | Date | Thu, 10 Oct 2013 19:45:21 +0200 | From | Ingo Molnar <> | Subject | Re: [PATCH] x86/efi: Add EFI framebuffer earlyprintk support |
| |
* Peter Jones <pjones@redhat.com> wrote:
> On Thu, Oct 10, 2013 at 07:28:44PM +0200, Ingo Molnar wrote: > > > > Is a non-32-bit framebuffer a possibility? If yes then it might be nice to > > emit an informative printk() here, so that users who try to enable EFI > > early-printk can at least see why it's not working. (Assuming they get to > > look at regular printk output, on a safe/working kernel.) > > Not really - the spec allows RGBx, BGRx, and for custom bit masks, but > they're define like: > > typedef struct { > UINT32 RedMask; > UINT32 GreenMask; > UINT32 BlueMask; > UINT32 ReservedMask; > } EFI_PIXEL_BITMASK;
Hm, that structure does not show up anywhere in the kernel that I can see.
How are those mask values to be interpreted? As regular bitmasks? Are bits in the masks set to 1 consecutively, starting from bit 0?
Also, the main question would be, what is the typical value for si->lfb_depth. 32 on almost all EFI systems? All around the map? Depends on what graphics state the EFI bootloader passes us?
Thanks,
Ingo
| |