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| author |   Sandor Bodo-Merle <sbodomerle@gmail.com> | 2021-06-22 17:26:30 +0200 |
|---|---|---|
| committer |   Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> | 2021-06-22 16:43:42 +0100 |
| commit | 2dc0a201d0f59e6818ef443609f0850a32910844 (patch) | |
| tree | 0c656222fbe4bbe90f70c1accda5828d7c850554 /drivers/pci/controller/pcie-iproc-msi.c | |
| parent | PCI: iproc: Fix multi-MSI base vector number allocation (diff) | |
| download | linux-dev-2dc0a201d0f59e6818ef443609f0850a32910844.tar.xz linux-dev-2dc0a201d0f59e6818ef443609f0850a32910844.zip | |
PCI: iproc: Support multi-MSI only on uniprocessor kernel
The interrupt affinity scheme used by this driver is incompatible with
multi-MSI as it implies moving the doorbell address to that of another MSI
group. This isn't possible for multi-MSI, as all the MSIs must have the
same doorbell address. As such it is restricted to systems with a single
CPU.
Link: https://lore.kernel.org/r/20210622152630.40842-2-sbodomerle@gmail.com
Fixes: fc54bae28818 ("PCI: iproc: Allow allocation of multiple MSIs")
Reported-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Sandor Bodo-Merle <sbodomerle@gmail.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Acked-by: Pali Rohár <pali@kernel.org>
Acked-by: Ray Jui <ray.jui@broadcom.com>
Diffstat (limited to 'drivers/pci/controller/pcie-iproc-msi.c')
| -rw-r--r-- | drivers/pci/controller/pcie-iproc-msi.c | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/drivers/pci/controller/pcie-iproc-msi.c b/drivers/pci/controller/pcie-iproc-msi.c index 557d93dcb3bc..81b4effeb130 100644 --- a/drivers/pci/controller/pcie-iproc-msi.c +++ b/drivers/pci/controller/pcie-iproc-msi.c @@ -171,7 +171,7 @@ static struct irq_chip iproc_msi_irq_chip = { static struct msi_domain_info iproc_msi_domain_info = { .flags = MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS | - MSI_FLAG_MULTI_PCI_MSI | MSI_FLAG_PCI_MSIX, + MSI_FLAG_PCI_MSIX, .chip = &iproc_msi_irq_chip, }; @@ -250,6 +250,9 @@ static int iproc_msi_irq_domain_alloc(struct irq_domain *domain, struct iproc_msi *msi = domain->host_data; int hwirq, i; + if (msi->nr_cpus > 1 && nr_irqs > 1) + return -EINVAL; + mutex_lock(&msi->bitmap_lock); /* @@ -540,6 +543,9 @@ int iproc_msi_init(struct iproc_pcie *pcie, struct device_node *node) mutex_init(&msi->bitmap_lock); msi->nr_cpus = num_possible_cpus(); + if (msi->nr_cpus == 1) + iproc_msi_domain_info.flags |= MSI_FLAG_MULTI_PCI_MSI; + msi->nr_irqs = of_irq_count(node); if (!msi->nr_irqs) { dev_err(pcie->dev, "found no MSI GIC interrupt\n"); |