Hi Lucas,

Thanks for the review.

On 21/03/2014 11:18, Lucas wrote:

Subject: Re: [PATCH v4 2/9] PCI: host: rcar: Add MSI support

Am Freitag, den 21.03.2014, 10:32 +0000 schrieb Phil Edworthy:

quoted

Signed-off-by: Phil Edworthy <redacted>
---
 drivers/pci/host/pcie-rcar.c | 232 

++++++++++++++++++++++++++++++++++++++++++-

quoted

 drivers/pci/host/pcie-rcar.h |   5 +
 2 files changed, 236 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/host/pcie-rcar.c 

b/drivers/pci/host/pcie-rcar.c

quoted

index 16670e5..cbbcd77 100644

--- a/drivers/pci/host/pcie-rcar.c
+++ b/drivers/pci/host/pcie-rcar.c

[...]

quoted

+
+static irqreturn_t rcar_pcie_msi_irq(int irq, void *data)
+{
+   struct rcar_pcie *pcie = data;
+   struct rcar_msi *msi = &pcie->msi;
+   unsigned long reg;
+
+   reg = pci_read_reg(pcie, PCIEMSIFR);
+
+   while (reg) {
+      unsigned int index = find_first_bit(&reg, 32);
+      unsigned int irq;
+
+      /* clear the interrupt */
+      pci_write_reg(pcie, 1 << index, PCIEMSIFR);
+
+      irq = irq_find_mapping(msi->domain, index);
+      if (irq) {
+         if (test_bit(index, msi->used))
+            generic_handle_irq(irq);
+         else
+            dev_info(pcie->dev, "unhandled MSI\n");
+      } else {
+         /*
+          * that's weird who triggered this?
+          * just clear it
+          */
+         dev_info(pcie->dev, "unexpected MSI\n");
+      }
+
+      /* see if there's any more pending in this vector */
+      reg = pci_read_reg(pcie, PCIEMSIFR);
+   }
+
+   return IRQ_HANDLED;
+}
+

From your DT binding it seems you have only one interrupt from the PCIe
core, shared between the MSI irqs and the PCI legacy interrupts.
This means this handler may get called without an MSI irq pending, so
this function really should have a path where it's returning IRQ_NONE.

Ah, yes you are right... though actually there are two interrupts, one has 
some MSI and INTx, the other has the rest of the MSIs.

Regards,
Lucas

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Pengutronix e.K.                           | Lucas Stach |
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Thanks
Phil