* PPC440EPx on Sequoia: /proc/iomem acts weird
@ 2007-11-09 18:30 Steven A. Falco
2007-11-09 18:35 ` Josh Boyer
0 siblings, 1 reply; 6+ messages in thread
From: Steven A. Falco @ 2007-11-09 18:30 UTC (permalink / raw)
To: linuxppc-dev
If I cat /proc/iomem on a Sequoia board, it never stops printing. Here
are the first 10 lines:
bash-3.00# head -10 /proc/iomem
e0000100-e000017f : usb
e0000100-e000017f : musbhsfc_udc
e0000300-e000038f : ehci_hcd
180000000-18fffffff : /plb/pci@1eec00000
1d0000000-1d0001fff : ndfc
1d0000000-1d0001fff : ndfc
1d0000000-1d0001fff : ndfc
1d0000000-1d0001fff : ndfc
1d0000000-1d0001fff : ndfc
1d0000000-1d0001fff : ndfc
Basically, the last line (regarding the nand flash) keeps repeating
"forever".
Is anyone else seeing this behavior? My kernel is 2.6.23 with Xenomai
patched in.
Steve
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: PPC440EPx on Sequoia: /proc/iomem acts weird 2007-11-09 18:30 PPC440EPx on Sequoia: /proc/iomem acts weird Steven A. Falco @ 2007-11-09 18:35 ` Josh Boyer 2007-11-09 18:46 ` Steven A. Falco 0 siblings, 1 reply; 6+ messages in thread From: Josh Boyer @ 2007-11-09 18:35 UTC (permalink / raw) To: Steven A. Falco; +Cc: linuxppc-dev On Fri, 09 Nov 2007 13:30:03 -0500 "Steven A. Falco" <sfalco@harris•com> wrote: > If I cat /proc/iomem on a Sequoia board, it never stops printing. Here > are the first 10 lines: > > bash-3.00# head -10 /proc/iomem > e0000100-e000017f : usb > e0000100-e000017f : musbhsfc_udc > e0000300-e000038f : ehci_hcd > 180000000-18fffffff : /plb/pci@1eec00000 > 1d0000000-1d0001fff : ndfc > 1d0000000-1d0001fff : ndfc > 1d0000000-1d0001fff : ndfc > 1d0000000-1d0001fff : ndfc > 1d0000000-1d0001fff : ndfc > 1d0000000-1d0001fff : ndfc > > Basically, the last line (regarding the nand flash) keeps repeating > "forever". > > Is anyone else seeing this behavior? My kernel is 2.6.23 with Xenomai > patched in. Erm.. 2.6.23? There is no Sequoia support in arch/ppc or arch/powerpc for 2.6.23 in the official trees. What is Xenomai? You should probably talk to them. josh ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: PPC440EPx on Sequoia: /proc/iomem acts weird 2007-11-09 18:35 ` Josh Boyer @ 2007-11-09 18:46 ` Steven A. Falco 2007-11-10 13:03 ` Stefan Roese 0 siblings, 1 reply; 6+ messages in thread From: Steven A. Falco @ 2007-11-09 18:46 UTC (permalink / raw) To: Josh Boyer; +Cc: linuxppc-dev [-- Attachment #1: Type: text/plain, Size: 1166 bytes --] I am using the Denx 2.6.32 kernel, which does have powerpc/sequoia. Xenomai is a real-time kernel built on Adeos/Ipipe. I'll dig into it further. Steve Josh Boyer wrote: > On Fri, 09 Nov 2007 13:30:03 -0500 > "Steven A. Falco" <sfalco@harris•com> wrote: > > >> If I cat /proc/iomem on a Sequoia board, it never stops printing. Here >> are the first 10 lines: >> >> bash-3.00# head -10 /proc/iomem >> e0000100-e000017f : usb >> e0000100-e000017f : musbhsfc_udc >> e0000300-e000038f : ehci_hcd >> 180000000-18fffffff : /plb/pci@1eec00000 >> 1d0000000-1d0001fff : ndfc >> 1d0000000-1d0001fff : ndfc >> 1d0000000-1d0001fff : ndfc >> 1d0000000-1d0001fff : ndfc >> 1d0000000-1d0001fff : ndfc >> 1d0000000-1d0001fff : ndfc >> >> Basically, the last line (regarding the nand flash) keeps repeating >> "forever". >> >> Is anyone else seeing this behavior? My kernel is 2.6.23 with Xenomai >> patched in. >> > > Erm.. 2.6.23? There is no Sequoia support in arch/ppc or arch/powerpc > for 2.6.23 in the official trees. What is Xenomai? You should > probably talk to them. > > josh > > [-- Attachment #2: Type: text/html, Size: 1626 bytes --] ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: PPC440EPx on Sequoia: /proc/iomem acts weird 2007-11-09 18:46 ` Steven A. Falco @ 2007-11-10 13:03 ` Stefan Roese 2007-11-12 15:36 ` Steven A. Falco 2007-11-12 19:25 ` Steven A. Falco 0 siblings, 2 replies; 6+ messages in thread From: Stefan Roese @ 2007-11-10 13:03 UTC (permalink / raw) To: linuxppc-dev Hi Steve, On Friday 09 November 2007, Steven A. Falco wrote: > I am using the Denx 2.6.32 kernel, which does have powerpc/sequoia. > Xenomai is a real-time kernel built on Adeos/Ipipe. I'll dig into it > further. Is this arch/ppc or arch/powerpc? I remember fixing this a while ago in arch/ppc: commit 67a35ce785b1d11d09bf528c166ea26d489a4bd6 Author: Stefan Roese <sr@denx•de> Date: Thu Aug 2 14:15:22 2007 +0200 ppc: Fix problem with recursive NDFC platform_device resource management This change fixes a problem with a resursive platform_device resource management of the AMCC 4xx NDFC. Without this fix a "cat /proc/iomem" leads to an infinite loop of printing the "ndfc-nand.0" resource. Signed-off-by: Stefan Roese <sr@denx•de> Best regards, Stefan ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: PPC440EPx on Sequoia: /proc/iomem acts weird 2007-11-10 13:03 ` Stefan Roese @ 2007-11-12 15:36 ` Steven A. Falco 2007-11-12 19:25 ` Steven A. Falco 1 sibling, 0 replies; 6+ messages in thread From: Steven A. Falco @ 2007-11-12 15:36 UTC (permalink / raw) To: Stefan Roese; +Cc: linuxppc-dev [-- Attachment #1: Type: text/plain, Size: 1667 bytes --] This is on arch/powerpc. I traced through the linked lists in resource.c. Here is a partial list, with the addresses changed to single upper-case letters for readability. Also "N" is a null pointer: r=A p=N s=N c=K r=K p=A s=M c=P r=M p=A s=R c=N r=R p=A s=B c=N r=B p=B s=J c=B r=J p=A s=C c=N r=C p=A s=D c=N r=D p=A s=E c=N r=E p=A s=F c=N r=F p=A s=G c=N r=G p=A s=H c=N r=H p=A s=N c=N r=B p=B s=J c=B r=J p=A s=C c=N r=C p=A s=D c=N r is the resource itself, p is the parent, s is the sibling, and c is the child. As you can see, most nodes point back to parent "A", and have null children. But one node, "B", points to itself both as parent and child. I believe this is the problem, but I haven't confirmed that, nor have I determined how the list gets into this state. Steve Stefan Roese wrote: > Hi Steve, > > On Friday 09 November 2007, Steven A. Falco wrote: > >> I am using the Denx 2.6.32 kernel, which does have powerpc/sequoia. >> Xenomai is a real-time kernel built on Adeos/Ipipe. I'll dig into it >> further. >> > > Is this arch/ppc or arch/powerpc? I remember fixing this a while ago in > arch/ppc: > > commit 67a35ce785b1d11d09bf528c166ea26d489a4bd6 > Author: Stefan Roese <sr@denx•de> > Date: Thu Aug 2 14:15:22 2007 +0200 > > ppc: Fix problem with recursive NDFC platform_device resource management > > This change fixes a problem with a resursive platform_device resource > management of the AMCC 4xx NDFC. Without this fix a "cat /proc/iomem" > leads to an infinite loop of printing the "ndfc-nand.0" resource. > > Signed-off-by: Stefan Roese <sr@denx•de> > > Best regards, > Stefan > > [-- Attachment #2: Type: text/html, Size: 2259 bytes --] ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: PPC440EPx on Sequoia: /proc/iomem acts weird 2007-11-10 13:03 ` Stefan Roese 2007-11-12 15:36 ` Steven A. Falco @ 2007-11-12 19:25 ` Steven A. Falco 1 sibling, 0 replies; 6+ messages in thread From: Steven A. Falco @ 2007-11-12 19:25 UTC (permalink / raw) To: Stefan Roese; +Cc: linuxppc-dev [-- Attachment #1: Type: text/plain, Size: 1670 bytes --] First I will say that I don't understand resources well enough to suggest a fix. But I have done a little poking around. In file arch/powerpc/platforms/44x/ppc4xx-nand.c I see one "struct resource", which is referenced by two "struct platform_device" items (ndfc_dev and nand_dev). In routine ppc4xx_setup_nand_node() we have two calls to platform_device_register(): platform_device_register(&ndfc_dev); platform_device_register(&nand_dev); If I comment out the second one, then there is no loop in the resource tree, and I can cat /proc/iomem just fine. If both calls are present, then cat /proc/iomem loops forever. So, just a wild guess - should there be two "struct resource"s, one for each platform_device, or is there some other way to break the loop in the tree? Steve Stefan Roese wrote: > Hi Steve, > > On Friday 09 November 2007, Steven A. Falco wrote: > >> I am using the Denx 2.6.32 kernel, which does have powerpc/sequoia. >> Xenomai is a real-time kernel built on Adeos/Ipipe. I'll dig into it >> further. >> > > Is this arch/ppc or arch/powerpc? I remember fixing this a while ago in > arch/ppc: > > commit 67a35ce785b1d11d09bf528c166ea26d489a4bd6 > Author: Stefan Roese <sr@denx•de> > Date: Thu Aug 2 14:15:22 2007 +0200 > > ppc: Fix problem with recursive NDFC platform_device resource management > > This change fixes a problem with a resursive platform_device resource > management of the AMCC 4xx NDFC. Without this fix a "cat /proc/iomem" > leads to an infinite loop of printing the "ndfc-nand.0" resource. > > Signed-off-by: Stefan Roese <sr@denx•de> > > Best regards, > Stefan > > [-- Attachment #2: Type: text/html, Size: 2231 bytes --] ^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2007-11-12 19:25 UTC | newest] Thread overview: 6+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2007-11-09 18:30 PPC440EPx on Sequoia: /proc/iomem acts weird Steven A. Falco 2007-11-09 18:35 ` Josh Boyer 2007-11-09 18:46 ` Steven A. Falco 2007-11-10 13:03 ` Stefan Roese 2007-11-12 15:36 ` Steven A. Falco 2007-11-12 19:25 ` Steven A. Falco
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