RE: 2.6.23.1 - sata_mv (7042) hang with large file operations

Morrison, Tom
2007-11-16T00:08:20Z

In the case of PCI (am no big expert on this)- I believe the code
allows you to address 32 bits at a time...you can see the the
effectve address resource address is some where around
0xea900000 - but, if you have PHYS_64BIT & PTE_64BIT -
you get resource_types of 64bits...that you can manipulate accordingly.

In the case of the eDMA - its 64bit dma operations - thus, you
setup the hi portion (by shifting twice by 16 (you get compiler
warnings if you try to shiftg the size of the offset - a bug IMHO))
and thus, can play the game I mentioned below and use the power
of the PEX inbound/outbound translation windows to move your data
correctly to the appropriate 32 bit location...

This game works fine very well for 2.6.11 + kernel - there are a few
more tests I need to do (like setting mem=<just below the PEX space>
and see if it works correctly...and then try again just a little bit above
PEX memory space (> ~0xea900000) - if it works below & doesn't work
above - it points to a problem with sata_mv doing some type of operation
outside the dma engine that is corrupting memory -

Thats another issue how does memory dribble/scribbling (only side affect
I can think of if something is going wrong with this translation)?

I'll try your 'patch' and see if that has any affect as well (and the
associated side-affects...)

t

________________________________

From: Mark Lord [mailto:liml@rtr.ca]
Sent: Thu 11/15/2007 5:14 PM
To: Morrison, Tom
Cc: Jeff Garzik; linux-ide@vger.kernel.org; linux-kernel@vger.kernel.org
Subject: Re: 2.6.23.1 - sata_mv (7042) hang with large file operations

Morrison, Tom wrote:
> The plot thickens - it looks like it might be some type
> of problem interacting with the setup of my 4Gig DDR memory
> and how I setup some translation windows in my MPC8548E
>
> I realized this morning that I have an inbound/ output PEX window
> Translation Setup for mapping all from/to PEX bus to outside
> the physical 4GIG memory space (i.e.: up at 0xC_xxxx_xxxx). Thus,
> all output operations that translation from 0xC_xxxx_xxxx to
> the pci 32 bit address of xxxx_xxxx) - and vice versa for for
> the inbound. Note: we also have a straight 1:1 translation mapping
> as well for the lower 4Gig - so that's why this worked without
> the below mentioned change...
>
> So, I changed the Request & Response Hi Addresses (which were
> Being shifted by 32 bits down anyways) and 'OR' that with my
> 0xC (so the effective 64bit DMA address is 0xC_xxxx_xxxx (where
> Xxxx_xxxx is the effective address). This was what we did to
> solve the problem with the Marvel Linux driver that we got from
> the Marvel site....
>
> This all works just fine with ONLY 2 gig of memory in the system
> (and still have these inbound/output pex translation windows),
> but fails when I put back the 4 Gig (and the 8Gig) DDR memory.
>
> Unfortunately, this still hasn't solved the problem though -
> so there is something else which I am not seeing?
..

I don't know much about how 32-bit PPC deals with memory addresses
that are more than 32-bits..

But does this patch have any effect:

--- old/drivers/ata/sata_mv.c 2007-10-12 12:43:44.000000000 -0400
+++ linux/drivers/ata/sata_mv.c 2007-11-15 17:12:24.000000000 -0500
@@ -685,7 +685,7 @@
{
int rc;

- if (!pci_set_dma_mask(pdev, DMA_64BIT_MASK)) {
+ if (0 && !pci_set_dma_mask(pdev, DMA_64BIT_MASK)) {
rc = pci_set_consistent_dma_mask(pdev, DMA_64BIT_MASK);
if (rc) {
rc = pci_set_consistent_dma_mask(pdev, DMA_32BIT_MASK);