arm: kernel: pci: remove pci=firmware command line parameter handling

RFC PATCH New Lorenzo Pieralisi 4 participants 8 messages Feb 29, 2016 – Mar 3, 2016

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Lorenzo Pieralisi

author

2016-02-29 17:41 UTC #0 lore raw

RFC PATCH 1/1 arm: kernel: pci: remove pci=firmware command line parameter handling

According to kernel documentation, the pci=firmware command line parameter is only meant to be used on IXP2000 ARM platforms to prevent the kernel from assigning PCI resources configured by the bootloader.

Since the IXP2000 ARM platforms support has been removed from the kernel in commit:

commit c65f2abf54a6 ("ARM: remove ixp23xx and ixp2000 platforms")

its platforms specific kernel parameters should be removed too from the kernel documentation along with the kernel code currently handling them in that they have just become obsolete.

This patch removes the pci=firmware command line parameter handling from ARM code and the related kernel parameters documentation section.

Signed-off-by Lorenzo Pieralisi <[email protected]>

Cc Arnd Bergmann <[email protected]>

Cc Lennert Buytenhek <[email protected]>

Cc Jonathan Corbet <[email protected]>

Cc Bjorn Helgaas <[email protected]>

Cc Rob Herring <[email protected]>

Cc Russell King <[email protected]>

---
 Documentation/kernel-parameters.txt | 5 -----
 arch/arm/kernel/bios32.c            | 3 ---
 2 files changed, 8 deletions(-)

Documentation/kernel-parameters.txt +0 -5

index 9a53c92..e213acc 100644
@@ -2875,11 +2875,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 				for broken drivers that don't call it.
 		skip_isa_align	[X86] do not align io start addr, so can
 				handle more pci cards
-		firmware	[ARM] Do not re-enumerate the bus but instead
-				just use the configuration from the
-				bootloader. This is currently used on
-				IXP2000 systems where the bus has to be
-				configured a certain way for adjunct CPUs.
 		noearly		[X86] Don't do any early type 1 scanning.
 				This might help on some broken boards which
 				machine check when some devices' config space

arch/arm/kernel/bios32.c +0 -3

index 066f7f9..05e61a2 100644
@@ -550,9 +550,6 @@ char * __init pcibios_setup(char *str)
 	if (!strcmp(str, "debug")) {
 		debug_pci = 1;
 		return NULL;
-	} else if (!strcmp(str, "firmware")) {
-		pci_add_flags(PCI_PROBE_ONLY);
-		return NULL;
 	}
 	return str;
 }

Signature · 1 line

2.5.1

Lennert Buytenhek

2016-02-29 17:42 UTC #1 lore raw

RFC PATCH 1/1 arm: kernel: pci: remove pci=firmware command line parameter handling

Quoted 17 lines · Lorenzo Pieralisi

According to kernel documentation, the pci=firmware command line parameter is only meant to be used on IXP2000 ARM platforms to prevent the kernel from assigning PCI resources configured by the bootloader.
Since the IXP2000 ARM platforms support has been removed from the kernel in commit:
commit c65f2abf54a6 ("ARM: remove ixp23xx and ixp2000 platforms")
its platforms specific kernel parameters should be removed too from the kernel documentation along with the kernel code currently handling them in that they have just become obsolete.
This patch removes the pci=firmware command line parameter handling from ARM code and the related kernel parameters documentation section.

Quoted 7 lines

Signed-off-by Lorenzo Pieralisi <[email protected]>
Cc Arnd Bergmann <[email protected]>
Cc Lennert Buytenhek <[email protected]>
Cc Jonathan Corbet <[email protected]>
Cc Bjorn Helgaas <[email protected]>
Cc Rob Herring <[email protected]>
Cc Russell King <[email protected]>

Acked-by Lennert Buytenhek <[email protected]>

Lorenzo Pieralisi

author

2016-03-01 09:56 UTC #2 lore raw

RFC PATCH 1/1 arm: kernel: pci: remove pci=firmware command line parameter handling

Quoted 27 lines · Lennert Buytenhek

Quoted 17 lines · Lorenzo Pieralisi
According to kernel documentation, the pci=firmware command line parameter is only meant to be used on IXP2000 ARM platforms to prevent the kernel from assigning PCI resources configured by the bootloader.
Since the IXP2000 ARM platforms support has been removed from the kernel in commit:
commit c65f2abf54a6 ("ARM: remove ixp23xx and ixp2000 platforms")
its platforms specific kernel parameters should be removed too from the kernel documentation along with the kernel code currently handling them in that they have just become obsolete.
This patch removes the pci=firmware command line parameter handling from ARM code and the related kernel parameters documentation section.
Quoted 7 lines
Signed-off-by Lorenzo Pieralisi <[email protected]>
Cc Arnd Bergmann <[email protected]>
Cc Lennert Buytenhek <[email protected]>
Cc Jonathan Corbet <[email protected]>
Cc Bjorn Helgaas <[email protected]>
Cc Rob Herring <[email protected]>
Cc Russell King <[email protected]>

Quoted 1 line

Acked-by Lennert Buytenhek <[email protected]>

Thank you Lennert, I take this as an acknowledgement that you are not aware of any other ARM platform using that kernel parameter other than IXP2000s, according to documentation there should not be any but it is a bit complicated to figure out.

Thanks,
Lorenzo

Lennert Buytenhek

2016-03-02 22:31 UTC #3 lore raw

RFC PATCH 1/1 arm: kernel: pci: remove pci=firmware command line parameter handling

Quoted 25 lines · Lorenzo Pieralisi

Quoted 25 lines
Quoted 24 lines
According to kernel documentation, the pci=firmware command line parameter is only meant to be used on IXP2000 ARM platforms to prevent the kernel from assigning PCI resources configured by the bootloader.
Since the IXP2000 ARM platforms support has been removed from the kernel in commit:
commit c65f2abf54a6 ("ARM: remove ixp23xx and ixp2000 platforms")
its platforms specific kernel parameters should be removed too from the kernel documentation along with the kernel code currently handling them in that they have just become obsolete.
This patch removes the pci=firmware command line parameter handling from ARM code and the related kernel parameters documentation section.
Signed-off-by Lorenzo Pieralisi <[email protected]>
Cc Arnd Bergmann <[email protected]>
Cc Lennert Buytenhek <[email protected]>
Cc Jonathan Corbet <[email protected]>
Cc Bjorn Helgaas <[email protected]>
Cc Rob Herring <[email protected]>
Cc Russell King <[email protected]>

Quoted 6 lines

Quoted 1 line
Acked-by Lennert Buytenhek <[email protected]>
Thank you Lennert, I take this as an acknowledgement that you are not aware of any other ARM platform using that kernel parameter other than IXP2000s, according to documentation there should not be any but it is a bit complicated to figure out.

I'm not aware of other platforms using this, but that might not say much, I've been out of the loop on Linux/ARM things for a while now.

Lorenzo Pieralisi

author

2016-03-03 10:46 UTC #4 lore raw

RFC PATCH 1/1 arm: kernel: pci: remove pci=firmware command line parameter handling

Quoted 29 lines · Lennert Buytenhek

Quoted 27 lines · Lorenzo Pieralisi
Quoted 26 lines
Quoted 17 lines
According to kernel documentation, the pci=firmware command line parameter is only meant to be used on IXP2000 ARM platforms to prevent the kernel from assigning PCI resources configured by the bootloader.
Since the IXP2000 ARM platforms support has been removed from the kernel in commit:
commit c65f2abf54a6 ("ARM: remove ixp23xx and ixp2000 platforms")
its platforms specific kernel parameters should be removed too from the kernel documentation along with the kernel code currently handling them in that they have just become obsolete.
This patch removes the pci=firmware command line parameter handling from ARM code and the related kernel parameters documentation section.
Quoted 7 lines
Signed-off-by Lorenzo Pieralisi <[email protected]>
Cc Arnd Bergmann <[email protected]>
Cc Lennert Buytenhek <[email protected]>
Cc Jonathan Corbet <[email protected]>
Cc Bjorn Helgaas <[email protected]>
Cc Rob Herring <[email protected]>
Cc Russell King <[email protected]>
Acked-by Lennert Buytenhek <[email protected]>

Quoted 7 lines

Quoted 4 lines
Thank you Lennert, I take this as an acknowledgement that you are not aware of any other ARM platform using that kernel parameter other than IXP2000s, according to documentation there should not be any but it is a bit complicated to figure out.
I'm not aware of other platforms using this, but that might not say much, I've been out of the loop on Linux/ARM things for a while now.

I think we should go ahead otherwise we are stuck forever with it, it is probably best for this patch to land in -next beginning of next cycle to unearth possible issues, that's the same thing we did for the latest changes in arm pcibios that we feared could trigger regressions.

Russell, what's your opinion on this ? Please let me know.

Thanks !
Lorenzo

Russell King - ARM Linux

2016-03-03 10:50 UTC #5 lore raw

RFC PATCH 1/1 arm: kernel: pci: remove pci=firmware command line parameter handling

Quoted 7 lines · Lorenzo Pieralisi

I think we should go ahead otherwise we are stuck forever with it, it is probably best for this patch to land in -next beginning of next cycle to unearth possible issues, that's the same thing we did for the latest changes in arm pcibios that we feared could trigger regressions.
Russell, what's your opinion on this ? Please let me know.

I'm happy with the suggested approach.

Thanks.

Signature · 3 lines

RMK's Patch system: http://www.arm.linux.org.uk/developer/patches/
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Bjorn Helgaas

2016-02-29 22:56 UTC #6 lore raw

RFC PATCH 1/1 arm: kernel: pci: remove pci=firmware command line parameter handling

In reply to Lorenzo Pieralisi

Quoted 13 lines · Lorenzo Pieralisi

According to kernel documentation, the pci=firmware command line parameter is only meant to be used on IXP2000 ARM platforms to prevent the kernel from assigning PCI resources configured by the bootloader.
Since the IXP2000 ARM platforms support has been removed from the kernel in commit:
commit c65f2abf54a6 ("ARM: remove ixp23xx and ixp2000 platforms")
its platforms specific kernel parameters should be removed too from the kernel documentation along with the kernel code currently handling them in that they have just become obsolete.

Quoted 5 lines

This patch removes the pci=firmware command line parameter handling from ARM code and the related kernel parameters documentation section.
Signed-off-by Lorenzo Pieralisi <[email protected]>

Acked-by Bjorn Helgaas <[email protected]>

It looks like Rob merged c65f2abf54a6, so maybe he will merge this as well? Otherwise I'd be happy to merge it; just let me know if you want me to.

Quoted 48 lines

Cc Arnd Bergmann <[email protected]>

Cc Lennert Buytenhek <[email protected]>

Cc Jonathan Corbet <[email protected]>

Cc Bjorn Helgaas <[email protected]>

Cc Rob Herring <[email protected]>

Cc Russell King <[email protected]>

---
 Documentation/kernel-parameters.txt | 5 -----
 arch/arm/kernel/bios32.c            | 3 ---
 2 files changed, 8 deletions(-)

Documentation/kernel-parameters.txt +0 -5

index 9a53c92..e213acc 100644
@@ -2875,11 +2875,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 				for broken drivers that don't call it.
 		skip_isa_align	[X86] do not align io start addr, so can
 				handle more pci cards
-		firmware	[ARM] Do not re-enumerate the bus but instead
-				just use the configuration from the
-				bootloader. This is currently used on
-				IXP2000 systems where the bus has to be
-				configured a certain way for adjunct CPUs.
 		noearly		[X86] Don't do any early type 1 scanning.
 				This might help on some broken boards which
 				machine check when some devices' config space

arch/arm/kernel/bios32.c +0 -3

index 066f7f9..05e61a2 100644
@@ -550,9 +550,6 @@ char * __init pcibios_setup(char *str)
 	if (!strcmp(str, "debug")) {
 		debug_pci = 1;
 		return NULL;
-	} else if (!strcmp(str, "firmware")) {
-		pci_add_flags(PCI_PROBE_ONLY);
-		return NULL;
 	}
 	return str;
 }

Signature · 6 lines

2.5.1

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Lorenzo Pieralisi

author

2016-03-01 09:48 UTC #7 lore raw

RFC PATCH 1/1 arm: kernel: pci: remove pci=firmware command line parameter handling

Quoted 14 lines · Bjorn Helgaas

Quoted 13 lines · Lorenzo Pieralisi
According to kernel documentation, the pci=firmware command line parameter is only meant to be used on IXP2000 ARM platforms to prevent the kernel from assigning PCI resources configured by the bootloader.
Since the IXP2000 ARM platforms support has been removed from the kernel in commit:
commit c65f2abf54a6 ("ARM: remove ixp23xx and ixp2000 platforms")
its platforms specific kernel parameters should be removed too from the kernel documentation along with the kernel code currently handling them in that they have just become obsolete.

Quoted 7 lines

Quoted 5 lines
This patch removes the pci=firmware command line parameter handling from ARM code and the related kernel parameters documentation section.
Signed-off-by Lorenzo Pieralisi <[email protected]>
Acked-by Bjorn Helgaas <[email protected]>

Thank you !

Quoted 3 lines

It looks like Rob merged c65f2abf54a6, so maybe he will merge this as well? Otherwise I'd be happy to merge it; just let me know if you want me to.

Hopefully the kernel parameter description matches current usage on ARM systems, it could affect all ARM 32-bit platforms (if any ?) that abused the pci=firmware parameter, it is just impossible for me to check (that's why I posted it as an RFC. It would be very good to remove that kernel parameter though).

Having said that, either way of merging it is fine by me, I can send it to Russell's patch system too, given that there are already patches queued to remove PCI_PROBE_ONLY from some PCI host controllers I am happy for it to go via PCI tree.

Rob, Russell, any preferences ?

Thanks !
Lorenzo

Quoted 50 lines

Quoted 49 lines

Cc Arnd Bergmann <[email protected]>

Cc Lennert Buytenhek <[email protected]>

Cc Jonathan Corbet <[email protected]>

Cc Bjorn Helgaas <[email protected]>

Cc Rob Herring <[email protected]>

Cc Russell King <[email protected]>

---
 Documentation/kernel-parameters.txt | 5 -----
 arch/arm/kernel/bios32.c            | 3 ---
 2 files changed, 8 deletions(-)

Documentation/kernel-parameters.txt +0 -5

index 9a53c92..e213acc 100644
@@ -2875,11 +2875,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 				for broken drivers that don't call it.
 		skip_isa_align	[X86] do not align io start addr, so can
 				handle more pci cards
-		firmware	[ARM] Do not re-enumerate the bus but instead
-				just use the configuration from the
-				bootloader. This is currently used on
-				IXP2000 systems where the bus has to be
-				configured a certain way for adjunct CPUs.
 		noearly		[X86] Don't do any early type 1 scanning.
 				This might help on some broken boards which
 				machine check when some devices' config space

arch/arm/kernel/bios32.c +0 -3

index 066f7f9..05e61a2 100644
@@ -550,9 +550,6 @@ char * __init pcibios_setup(char *str)
 	if (!strcmp(str, "debug")) {
 		debug_pci = 1;
 		return NULL;
-	} else if (!strcmp(str, "firmware")) {
-		pci_add_flags(PCI_PROBE_ONLY);
-		return NULL;
 	}
 	return str;
 }

Signature · 6 lines

2.5.1

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