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authorMatthew Garrett <mjg@redhat.com>2012-03-27 10:17:41 -0400
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2012-04-02 09:53:10 -0700
commite277a09f64ac659407582c2182b245afa66dcebc (patch)
treec0b2891f4825bde0e5d55e0a3b51a4f03471247f /drivers/pci/pcie/aspm.c
parent46979bfe3c1c2435f7f8190ff0c0994de3cfc471 (diff)
ASPM: Fix pcie devices with non-pcie children
commit c9651e70ad0aa499814817cbf3cc1d0b806ed3a1 upstream. Since 3.2.12 and 3.3, some systems are failing to boot with a BUG_ON. Some other systems using the pata_jmicron driver fail to boot because no disks are detected. Passing pcie_aspm=force on the kernel command line works around it. The cause: commit 4949be16822e ("PCI: ignore pre-1.1 ASPM quirking when ASPM is disabled") changed the behaviour of pcie_aspm_sanity_check() to always return 0 if aspm is disabled, in order to avoid cases where we changed ASPM state on pre-PCIe 1.1 devices. This skipped the secondary function of pcie_aspm_sanity_check which was to avoid us enabling ASPM on devices that had non-PCIe children, causing trouble later on. Move the aspm_disabled check so we continue to honour that scenario. Addresses https://bugzilla.kernel.org/show_bug.cgi?id=42979 and http://bugs.debian.org/665420 Reported-by: Romain Francoise <romain@orebokech.com> # kernel panic Reported-by: Chris Holland <bandidoirlandes@gmail.com> # disk detection trouble Signed-off-by: Matthew Garrett <mjg@redhat.com> Tested-by: Hatem Masmoudi <hatem.masmoudi@gmail.com> # Dell Latitude E5520 Tested-by: janek <jan0x6c@gmail.com> # pata_jmicron with JMB362/JMB363 [jn: with more symptoms in log message] Signed-off-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/pci/pcie/aspm.c')
-rw-r--r--drivers/pci/pcie/aspm.c13
1 files changed, 10 insertions, 3 deletions
diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
index 24f049e7395..22751622568 100644
--- a/drivers/pci/pcie/aspm.c
+++ b/drivers/pci/pcie/aspm.c
@@ -500,9 +500,6 @@ static int pcie_aspm_sanity_check(struct pci_dev *pdev)
int pos;
u32 reg32;
- if (aspm_disabled)
- return 0;
-
/*
* Some functions in a slot might not all be PCIe functions,
* very strange. Disable ASPM for the whole slot
@@ -511,6 +508,16 @@ static int pcie_aspm_sanity_check(struct pci_dev *pdev)
pos = pci_pcie_cap(child);
if (!pos)
return -EINVAL;
+
+ /*
+ * If ASPM is disabled then we're not going to change
+ * the BIOS state. It's safe to continue even if it's a
+ * pre-1.1 device
+ */
+
+ if (aspm_disabled)
+ continue;
+
/*
* Disable ASPM for pre-1.1 PCIe device, we follow MS to use
* RBER bit to determine if a function is 1.1 version device