[+cc Thomas, Ley Foon]
On Sat, Jun 17, 2017 at 12:57:38PM -0700, Paul Burton wrote:
> The driver expects to use hardware IRQ numbers 1 through 4 for INTX
> interrupts, but only creates an IRQ domain of size 4 (ie. IRQ numbers 0
> through 3). This results in a warning from irq_domain_associate when it
> is called with hwirq=4:
>
> WARNING: CPU: 0 PID: 1 at kernel/irq/irqdomain.c:365
> irq_domain_associate+0x170/0x220
> error: hwirq 0x4 is too large for dummy
> Modules linked in:
> CPU: 0 PID: 1 Comm: swapper/0 Tainted: G W
> 4.12.0-rc5-00126-g19e1b3a10aad-dirty #427
> Stack : 0000000000000000 0000000000000004 0000000000000006 ffffffff8092c78a
> 0000000000000061 ffffffff8018bf60 0000000000000000 0000000000000000
> ffffffff8088c287 ffffffff80811d18 a8000000ffc60000 ffffffff80926678
> 0000000000000001 0000000000000000 ffffffff80887880 ffffffff80960000
> ffffffff80920000 ffffffff801e6744 ffffffff80887880 a8000000ffc4f8f8
> 000000000000089c ffffffff8018d260 0000000000010000 ffffffff80811d18
> 0000000000000000 0000000000000001 0000000000000000 0000000000000000
> 0000000000000000 a8000000ffc4f840 0000000000000000 ffffffff8042cf34
> 0000000000000000 0000000000000000 0000000000000000 0000000000040c00
> 0000000000000000 ffffffff8010d1c8 0000000000000000 ffffffff8042cf34
> ...
> Call Trace:
> [<ffffffff8010d1c8>] show_stack+0x80/0xa0
> [<ffffffff8042cf34>] dump_stack+0xd4/0x110
> [<ffffffff8013ea98>] __warn+0xf0/0x108
> [<ffffffff8013eb14>] warn_slowpath_fmt+0x3c/0x48
> [<ffffffff80196528>] irq_domain_associate+0x170/0x220
> [<ffffffff80196bf0>] irq_create_mapping+0x88/0x118
> [<ffffffff801976a8>] irq_create_fwspec_mapping+0xb8/0x320
> [<ffffffff80197970>] irq_create_of_mapping+0x60/0x70
> [<ffffffff805d1318>] of_irq_parse_and_map_pci+0x20/0x38
> [<ffffffff8049c210>] pci_fixup_irqs+0x60/0xe0
> [<ffffffff8049cd64>] xilinx_pcie_probe+0x28c/0x478
> [<ffffffff804e8ca8>] platform_drv_probe+0x50/0xd0
> [<ffffffff804e73a4>] driver_probe_device+0x2c4/0x3a0
> [<ffffffff804e7544>] __driver_attach+0xc4/0xd0
> [<ffffffff804e5254>] bus_for_each_dev+0x64/0xa8
> [<ffffffff804e5e40>] bus_add_driver+0x1f0/0x268
> [<ffffffff804e8000>] driver_register+0x68/0x118
> [<ffffffff801001a4>] do_one_initcall+0x4c/0x178
> [<ffffffff808d3ca8>] kernel_init_freeable+0x204/0x2b0
> [<ffffffff80730b68>] kernel_init+0x10/0xf8
> [<ffffffff80106218>] ret_from_kernel_thread+0x14/0x1c
>
> This patch avoids that warning by creating the legacy IRQ domain with
> size 5 rather than 4, allowing it to cover the hwirq=4/INTD case.
>
> Signed-off-by: Paul Burton <paul.burton@xxxxxxxxxx>
> Cc: Bharat Kumar Gogada <bharatku@xxxxxxxxxx>
> Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
> Cc: Michal Simek <michal.simek@xxxxxxxxxx>
> Cc: Ravikiran Gummaluri <rgummal@xxxxxxxxxx>
> Cc: linux-pci@xxxxxxxxxxxxxxx
>
> ---
>
> Changes in v5:
> - New patch; replacing "PCI: xilinx: Fix INTX irq dispatch".
>
> Changes in v4: None
> Changes in v3: None
> Changes in v2: None
>
> drivers/pci/host/pcie-xilinx.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/pci/host/pcie-xilinx.c b/drivers/pci/host/pcie-xilinx.c
> index 2fe2df51f9f8..94c71fb91648 100644
> --- a/drivers/pci/host/pcie-xilinx.c
> +++ b/drivers/pci/host/pcie-xilinx.c
> @@ -524,7 +524,7 @@ static int xilinx_pcie_init_irq_domain(struct xilinx_pcie_port *port)
> return -ENODEV;
> }
>
> - port->leg_domain = irq_domain_add_linear(pcie_intc_node, 4,
> + port->leg_domain = irq_domain_add_linear(pcie_intc_node, 1 + 4,
I don't understand this. Several drivers call irq_domain_add_linear() with
a size of 4:
dra7xx_pcie_init_irq_domain
ks_dw_pcie_host_init
advk_pcie_init_irq_domain
faraday_pci_setup_cascaded_irq
rockchip_pcie_init_irq_domain
nwl_pcie_init_irq_domain
Only one other in drivers/pci uses a size of 5:
altera_pcie_init_irq_domain
Why can't we use a size of 4 for all of them? We only have INTA-INTD. Are
altera and xilinx missing something to apply an offset from the 0-3 space
to the 1-4 space?
> &intx_domain_ops,
> port);
> if (!port->leg_domain) {
> --
> 2.13.1
>
