* Stephen Warren wrote: > On 06/11/2012 09:05 AM, Thierry Reding wrote: > > This commit adds support for message signaled interrupts to the Tegra > > PCIe controller. Based on code by Krishna Kishore <[email protected]>. > > > diff --git a/arch/arm/mach-tegra/pcie.c b/arch/arm/mach-tegra/pcie.c > > > +static irqreturn_t tegra_pcie_msi_irq(int irq, void *data) > ... > > + irq = irq_find_mapping(pcie->msi->domain, index); > > + if (irq) { > > + if (test_bit(index, pcie->msi->used)) > > + generic_handle_irq(irq); > > This invokes the handler first ... > > ... > > + /* clear the interrupt */ > > + afi_writel(pcie, 1 << offset, AFI_MSI_VEC0 + i * 4); > > + /* see if there's any more pending in this vector */ > > + reg = afi_readl(pcie, AFI_MSI_VEC0 + i * 4); > > ... then clears the interrupt status in the PCIe controller. Won't that > lose interrupts if one is raised between when the handler clears the > root-cause, and when this code clears the received interrupt status?
It certainly doesn't follow the conventional way of clearing the interrupt first. I carried this from the original MSI patch, but I'll move the interrupt clearing up and retest. > > +static int tegra_pcie_disable_msi(struct platform_device *pdev) > > Should this free pcie->msi->pages? Yes it should. I actually mention making that change in the changelog but in fact didn't. > Why allocate pcie->msi separately; why not include the fields directly > into struct tegra_pcie_info *pcie? For one I find this easier to read. If this wasn't a separate structure, each of the individual fields would get an msi_ prefix anyway so there isn't much to be gained from keeping them directly in tegra_pcie_info. Second, and more importantly, this will keep the size of struct tegra_pcie_info smaller if PCI_MSI is not selected because there is just one unused pointer instead of five unused fields. Thierry
pgppqXvAJGzzN.pgp
Description: PGP signature
_______________________________________________ devicetree-discuss mailing list [email protected] https://lists.ozlabs.org/listinfo/devicetree-discuss
