Re: [Qemu-devel] [PATCH] PL011: Fix ID reporting

[Marek Vasut <marek.vasut@gmail.com>]

> On 7 January 2012 20:11, Marek Vasut <marek.vasut@gmail.com> wrote:
> > The AMBA IDs are supposed to be at the end of 0x2000 block, which the
> > PL011 UART allocates. Current QEMU implementation puts those IDs at
> > 0x1000 offset, which is wrong. The QEMU implementation also allocates
> > only 0x1000 instead of 0x2000 of space.
> 
> Why do you think this change is correct? The PL011 TRM
> http://infocenter.arm.com/help/topic/com.arm.doc.ddi0183g/I18381.html
> says the ID registers are at 0xFE0..0xFFC.
> and for instance on the PBX-A9 devboard:
> http://infocenter.arm.com/help/topic/com.arm.doc.dui0440b/Bbajihec.html
> the UARTs are at 0x10009000, 0x1000A000, 0x1000B000, 0x1000C000, so
> they clearly can't be 0x2000 in size.

Then we have a problem, because eg. on freescale mx28 they are 0x2000 big. The 
only conclusion I can draw from this is that the size of the segment that can be 
assigned to PL011 is variable and the ID-octet is always at the end.

M
> 
> -- PMM