On Tue, Aug 15, 2017 at 04:38:38PM -0500, Bjorn Helgaas wrote:
> Use the PCI_NUM_INTX macro to indicate the number of PCI INTx interrupts
> rather than the magic number 4. This makes it clearer where the number
> comes from & what it relates to.
>
> Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
> Cc: Kishon Vijay Abraham I <kishon@xxxxxx>
> ---
> drivers/pci/dwc/pci-dra7xx.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/pci/dwc/pci-dra7xx.c b/drivers/pci/dwc/pci-dra7xx.c
> index f2fc5f47064e..30131ecaadea 100644
> --- a/drivers/pci/dwc/pci-dra7xx.c
> +++ b/drivers/pci/dwc/pci-dra7xx.c
> @@ -238,7 +238,7 @@ static int dra7xx_pcie_init_irq_domain(struct pcie_port *pp)
> return -ENODEV;
> }
>
> - dra7xx->irq_domain = irq_domain_add_linear(pcie_intc_node, 4,
> + dra7xx->irq_domain = irq_domain_add_linear(pcie_intc_node, PCI_NUM_INTX,
> &intx_domain_ops, pp);
> if (!dra7xx->irq_domain) {
> dev_err(dev, "Failed to get a INTx IRQ domain\n");
>
Oops. I think this patch is OK as far as it goes, but Kishon
confirmed [1] that INTD was broken in dra7xx, and AFAIK it's still
broken, so maybe we need to also use pci_irqd_intx_xlate() as in the
following?
[1] https://lkml.org/lkml/2016/9/14/241
commit 569f29aa4ff0ab4bd4d1782b3a806a7561fe9db5
Author: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Date: Tue Aug 15 16:28:27 2017 -0500
PCI: dra7xx: Translate INTx range to hwirqs 0-3
The pci-dra7xx driver creates an IRQ domain of size 4 for legacy PCI INTx
interrupts, which at first glance seems reasonable since there are 4 possible
such interrupts. Unfortunately the driver then proceeds to use the range 1-4
as the hwirq numbers for INTA-INTD, causing warnings & broken interrupts when
attempting to use INTD/hwirq=4 due to it being beyond the range of the IRQ
domain:
WARNING: CPU: 0 PID: 1 at kernel/irq/irqdomain.c:342 irq_domain_associate+0x12c/0x1c4
error: hwirq 0x4 is too large for dummy
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.8.0-rc6-01351-gd4fcf3d-dirty #15
Hardware name: Generic DRA72X (Flattened Device Tree)
(unwind_backtrace) from [<c010c264>] (show_stack+0x10/0x14)
(show_stack) from [<c048f3ec>] (dump_stack+0xac/0xe0)
(dump_stack) from [<c0138a74>] (__warn+0xd8/0x104)
(__warn) from [<c0138ad4>] (warn_slowpath_fmt+0x34/0x44)
(warn_slowpath_fmt) from [<c01a9944>] (irq_domain_associate+0x12c/0x1c4)
(irq_domain_associate) from [<c01aa158>] (irq_create_mapping+0x64/0xcc)
(irq_create_mapping) from [<c01aa848>] (irq_create_fwspec_mapping+0xac/0x2fc)
(irq_create_fwspec_mapping) from [<c01aaaec>] (irq_create_of_mapping+0x54/0x5c)
(irq_create_of_mapping) from [<c0668b04>] (of_irq_parse_and_map_pci+0x24/0x2c)
(of_irq_parse_and_map_pci) from [<c04ea578>] (pci_fixup_irqs+0x44/0xb8)
(pci_fixup_irqs) from [<c04eb8dc>] (dw_pcie_host_init+0x234/0x3e4)
(dw_pcie_host_init) from [<c0b38fa4>] (dra7xx_pcie_probe+0x418/0x5c4)
(dra7xx_pcie_probe) from [<c0557260>] (platform_drv_probe+0x4c/0xb0)
Fix this by making use of the new pci_irqd_intx_xlate() helper to translate
the INTx 1-4 range into the 0-3 range suitable for the IRQ domain of size
4, and stop adding 1 to the hwirq number decoded from the interrupt FIFO
which is already in the range 0-3.
Whilst we're here we switch to using PCI_NUM_INTX rather than the magic
number 4, making it clearer what the 4 means.
Based-on-similar-patches-by: Paul Burton <paul.burton@xxxxxxxxxx>
Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Cc: Kishon Vijay Abraham I <kishon@xxxxxx>
diff --git a/drivers/pci/dwc/pci-dra7xx.c b/drivers/pci/dwc/pci-dra7xx.c
index f2fc5f47064e..55f16fcf701d 100644
--- a/drivers/pci/dwc/pci-dra7xx.c
+++ b/drivers/pci/dwc/pci-dra7xx.c
@@ -223,6 +223,7 @@ static int dra7xx_pcie_intx_map(struct irq_domain *domain, unsigned int irq,
static const struct irq_domain_ops intx_domain_ops = {
.map = dra7xx_pcie_intx_map,
+ .xlate = pci_irqd_intx_xlate,
};
static int dra7xx_pcie_init_irq_domain(struct pcie_port *pp)
@@ -238,7 +239,7 @@ static int dra7xx_pcie_init_irq_domain(struct pcie_port *pp)
return -ENODEV;
}
- dra7xx->irq_domain = irq_domain_add_linear(pcie_intc_node, 4,
+ dra7xx->irq_domain = irq_domain_add_linear(pcie_intc_node, PCI_NUM_INTX,
&intx_domain_ops, pp);
if (!dra7xx->irq_domain) {
dev_err(dev, "Failed to get a INTx IRQ domain\n");
