[OpenBIOS] [PATCH 0/5] v1 alternative implementation of sparc64 boot memory mapping

[Andreas Färber]

Am 27.12.2009 um 14:46 schrieb Igor Kovalenko:

> On Sun, Dec 27, 2009 at 4:37 PM, Andreas Färber <andreas.faerber at web.de 
> > wrote:
>> Hello,
>>
>> Am 27.12.2009 um 12:43 schrieb Igor V. Kovalenko:
>>
>>> The following series implements alternative approach
>>> to solve issue where qemu provides i/o and pci memory
>>> spaces within physical RAM address space, which makes
>>> low memory addresses unusable.
>>>
>>> Instead of changing qemu to move i/o and pci spaces
>>> out of RAM space we can remap 64M of i/o and pci
>>> spaces to above 32bit accessible by client program.
>>> Then we map physical RAM at 64M offset to start of
>>> virtual memory.
>>>
>>> A few extra changes are required. At very least we
>>> need to find where framebuffer virtual address is
>>> placed by startup code, helper change is provided.
>>>
>>> NOTE: this approach may hide up to 128M from client
>>> allocations, therefore default qemu memory size
>>> is not sufficient. Please use at least '-m 256'
>>> on qemu command line to test with these changes.
>>>
>>> In my test these series are as efficient as
>>> qemu change to remap i/o and pci spaces in
>>> allowing milax032sparc.iso to not step over
>>> cmd646 registers. Currently milax loader
>>> gets a bit further and fails with
>>>
>>> Can't open /ramdisk-root
>>> byte-load: exception caught!
>>
>> I can confirm this behavior of milax032sparc.iso (with -m 256).
>>
>> debian-40r3-sparc-CD-1.iso however fails as follows, even with -m  
>> 1024:
>>
>> boot:
>> Allocated 8 Megs of memory at 0x40000000 for kernel
>> Loaded kernel version 2.6.18
>> Loading initial ramdisk (3882238 bytes at 0x8C00000 phys, 0x40C00000
>> virt)...
>> -
>> Unhandled Exception 0x0000000000000020
>> PC = 0x00000000005154dc NPC = 0x00000000005154e0
>> Stopping execution
>>
>> That's just before "Remapping the kernel...".
>
> I wonder if it worked before the proposed change.

Yes.

> Is the image available somewhere so I can take a look?

Try this one:
http://cdimage.debian.org/cdimage/archive/4.0_r8/sparc/iso-cd/debian-40r8-sparc-businesscard.iso

> I only have debian-40r4a-sparc-businesscard.iso and
> it keeps failing with inconsistent console (no change here).

I remember getting that message on some host, too.


For debian-503-sparc-businesscard.iso with your patches I get:

boot:
Allocated 8 Megs of memory at 0x40000000 for kernel
Loaded kernel version 2.6.26
Loading initial ramdisk (4311252 bytes at 0x8C00000 phys, 0x40C00000  
virt)...
|
[    0.000000] PROMLIB: Sun IEEE Boot Prom 'OBP 3.10.24 1999/01/01  
01:01'
[    0.000000] PROMLIB: Root node compatible: sun4u
[    0.000000] Initializing cgroup subsys cpu
[    0.000000] Linux version 2.6.26-2-sparc64 (Debian 2.6.26-19) (dannf at debian.org 
) (gcc version 4.1.3 20080704 (prerelease) (Debian 4.1.2-25)) #1 Thu  
Aug 20 15:21:01 UTC 2009
[    0.000000] console [earlyprom0] enabled
[    0.000000] ARCH: SUN4U
[    0.000000] Ethernet address: 52:54:00:12:34:56
Unhandled Exception 0x0000000000000020
PC = 0x000000000055049c NPC = 0x00000000005504a0
Stopping execution

With vanilla r647 I get:

boot:
Allocated 8 Megs of memory at 0x40000000 for kernel
Loaded kernel version 2.6.26
Loading initial ramdisk (4311252 bytes at 0xC00000 phys, 0x40C00000  
virt)...
qemu: unsupported keyboard cmd=0x62
zqemu: unsupported keyboard cmd=0x27

Andreas