Re: [PATCH 1/2] powerpc: disable MSI using new interface if possible
flat view
From: Nishanth Aravamudan <hidden>
Date: 2011-03-03 19:44:19
On 03.03.2011 [11:39:23 -0800], Nishanth Aravamudan wrote:
On upcoming hardware, we have a PCI adapter with two functions, one of which uses MSI and the other uses MSI-X. This adapter, when MSI is disabled using the "old" firmware interface (RTAS_CHANGE_FN), still signals an MSI-X interrupt and triggers an EEH. We are working with the vendor to ensure that the hardware is not at fault, but if we use the "new" interface (RTAS_CHANGE_MSI_FN) to disable MSI, we also automatically disable MSI-X and the adapter does not appear to signal any stray MSI-X interrupt. Signed-off-by: Nishanth Aravamudan <redacted> Cc: Milton Miller <redacted> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <redacted>
Sorry, I fudged my git-send-email config, apologies that the Cc's above weren't actually used in the original!
--- This is effectively a PCI quirk, but I'm not sure how to do a architecture-specific quirk (looking through the code now). If anyone has any pointers, I'd appreciate it!
If this would be preferred, I think I see now how it would be done and can work on a different patch that only makes this change for this device. Thanks, Nish
quoted hunk ↗ jump to hunk
arch/powerpc/platforms/pseries/msi.c | 14 ++++++++++++-- 1 files changed, 12 insertions(+), 2 deletions(-)diff --git a/arch/powerpc/platforms/pseries/msi.c b/arch/powerpc/platforms/pseries/msi.c index 1164c34..9434576 100644 --- a/arch/powerpc/platforms/pseries/msi.c +++ b/arch/powerpc/platforms/pseries/msi.c@@ -93,8 +93,18 @@ static void rtas_disable_msi(struct pci_dev *pdev) if (!pdn) return; - if (rtas_change_msi(pdn, RTAS_CHANGE_FN, 0) != 0) - pr_debug("rtas_msi: Setting MSIs to 0 failed!\n"); + /* + * disabling MSI with the explicit interface also disables MSI-X + */ + if (rtas_change_msi(pdn, RTAS_CHANGE_MSI_FN, 0) != 0) { + /* + * may have failed due to lacking + * "ibm,change-msix-capable" property + */ + if (rtas_change_msi(pdn, RTAS_CHANGE_FN, 0) != 0) { + pr_debug("rtas_msi: Setting MSIs to 0 failed!\n"); + } + } } static int rtas_query_irq_number(struct pci_dn *pdn, int offset)-- 1.7.1 _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
-- Nishanth Aravamudan [off-list ref] IBM Linux Technology Center