On Mon, Jun 17, 2019 at 10:34:35AM +0000, Z.q. Hou wrote:

[...]

quoted

There is nothing obvious. Write what you are fixing in the commit log and I will
apply the patch, I won't write the commit log for you. Anyone should be able
to understand why a patch was needed by reading the commit log, it is as
important as writing the code itself.

With the flag MSI_FLAG_MULTI_PCI_MSI, when the Endpoint allocates
multiple MSI, it will trigger the "WARN_ON(nr_irqs != 1);" in
mobiveil_irq_msi_domain_alloc(), this is the issue this patch want to
fix. 

And that's wrong. Marc explained why this controller does not support
Multi MSI and that's what should go in the commit log, triggering
a WARN_ON is the least of the problems (and the WARN_ON can even
be removed after this patch is applied), if it was used as a bandaid
to prevent allocating Multi MSI it is even more broken.

Lorenzo

Thanks,
Zhiqiang

quoted

Thanks,
Lorenzo

quoted

Thanks,
Zhiqiang

quoted

Lorenzo

quoted

Subbu, did you test with Endpoint supporting multi MSI?

Thanks,
Zhiqiang

quoted

Thanks,
Lorenzo

quoted

Fixes: 1e913e58335f ("PCI: mobiveil: Add MSI support")
Signed-off-by: Hou Zhiqiang <Zhiqiang.Hou@nxp.com>
Reviewed-by: Minghuan Lian <Minghuan.Lian@nxp.com>
---
V5:
 - Corrected the subject.

 drivers/pci/controller/pcie-mobiveil.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/pci/controller/pcie-mobiveil.c

b/drivers/pci/controller/pcie-mobiveil.c
index 563210e731d3..a0dd337c6214 100644

--- a/drivers/pci/controller/pcie-mobiveil.c
+++ b/drivers/pci/controller/pcie-mobiveil.c

@@ -703,7 +703,7 @@ static struct irq_chip

mobiveil_msi_irq_chip = {

 static struct msi_domain_info mobiveil_msi_domain_info = {
 	.flags	= (MSI_FLAG_USE_DEF_DOM_OPS |

MSI_FLAG_USE_DEF_CHIP_OPS |

quoted

-		   MSI_FLAG_MULTI_PCI_MSI | MSI_FLAG_PCI_MSIX),
+		   MSI_FLAG_PCI_MSIX),
 	.chip	= &mobiveil_msi_irq_chip,
 };

--
2.17.1

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