Re: [Qemu-devel] [5706] Implement LSI53C895A quirks exposed by OpenServer (Justin Chevrier).

[Ryan Harper]

* Andrzej Zaborowski <address@hidden> [2008-11-12 10:50]:
> Revision: 5706
>           http://svn.sv.gnu.org/viewvc/?view=rev&root=qemu&revision=5706
> Author:   balrog
> Date:     2008-11-12 16:41:32 +0000 (Wed, 12 Nov 2008)
> 
> Log Message:
> -----------
> Implement LSI53C895A quirks exposed by OpenServer (Justin Chevrier).
> 
> After going through the debug log and scratching my head for quite some
> time. I found the following:
> 
> The problem was with this block move:
> 
> lsi_scsi: SCRIPTS dsp=0fae8e50 opcode 01000028 arg 00f63c40
> lsi_scsi: DMA addr=0x00f63c40 len=36
> 
> The number of bytes to be transferred (len) should be 40 which corresponds
> to the block transfer of length 0x28 (from opcode 01000028). Instead we
> have a length of 36 (0x24). The code responsible for this is (in
> 'lsi_do_dma'):
> 
> if (count > s->current_dma_len)
>    count = s->current_dma_len;
> 
> Basically we're overwriting the length 40 with the value 36 which I
> think we just left over in that variable from an earlier transfer. In my
> patch below I initialize s->current_dma_len to s->dbc before we begin
> the DMA transfer during Data In phase.
> 
> The attached patch gets Openserver 5.0.5 past the hardware detection
> (and it lists the hard drive to boot, woohoo). It appears to stop a
> little while later (doesn't seem SCSI related), but it's been so long since
> I've booted Openserver I'm not sure what's supposted to happen after the HW
> detection using the boot/root disks.
> 
> Props go to Craig Ringer for the initial post and the code that he posted
> some of which is in this patch.

This patch breaks WinXP SP3 32-bit install to scsi device.  After
attempting to format a partition on the scsi device, Windows says there
is an error formating the partition.  If I revert the patch, formating
and installation to a scsi disk works ok.

I haven't dug into what part of the patch is breaking it just yet, but
plan to do so.


-- 
Ryan Harper
Software Engineer; Linux Technology Center
IBM Corp., Austin, Tx
address@hidden