PCI: Add pci_irq_type() to query the allocated interrupt typegrafted

Add a helper that returns PCI_IRQ_MSIX, PCI_IRQ_MSI, or PCI_IRQ_INTX
based on the interrupt type the PCI core selected after
pci_alloc_irq_vectors().

Several drivers already open-code this check against pdev->msix_enabled
and pdev->msi_enabled, or even open code this helper [1].

A common helper avoids the duplication and keeps drivers from accessing
the bitfield directly (see also [2]).

Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: John Hubbard <jhubbard@nvidia.com>
Link: https://elixir.bootlin.com/linux/v7.1/source/drivers/net/ethernet/aquantia/atlantic/aq_pci_func.c#L196 [1]
Inspired-by: John Hubbard <jhubbard@nvidia.com>
Link: https://lore.kernel.org/all/DKKG2QM3YJYB.Z2H2B2UXJ75N@kernel.org/ [2]
Reviewed-by: Gary Guo <gary@garyguo.net>
Link: https://patch.msgid.link/20260813165234.620555-5-dakr@kernel.org
[ Add missing pci_irq_type() stub for CONFIG_PCI=n. ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>

1 files changed, 70 insertions, 0 deletions

diff --git a/Documentation/ABI/testing/debugfs-scmi b/Documentation/ABI/testing/debugfs-scmi
new file mode 100644
index 000000000..ee7179ab2
--- /dev/null
+++ b/Documentation/ABI/testing/debugfs-scmi
@@ -0,0 +1,70 @@
+What:		/sys/kernel/debug/scmi/<n>/instance_name
+Date:		March 2023
+KernelVersion:	6.3
+Contact:	cristian.marussi@arm.com
+Description:	The name of the underlying SCMI instance <n> described by
+		all the debugfs accessors rooted at /sys/kernel/debug/scmi/<n>,
+		expressed as the full name of the top DT SCMI node under which
+		this SCMI instance is rooted.
+Users:		Debugging, any userspace test suite
+
+What:		/sys/kernel/debug/scmi/<n>/atomic_threshold_us
+Date:		March 2023
+KernelVersion:	6.3
+Contact:	cristian.marussi@arm.com
+Description:	An optional time value, expressed in microseconds, representing,
+		on this SCMI instance <n>, the threshold above which any SCMI
+		command, advertised to have an higher-than-threshold execution
+		latency, should not be considered for atomic mode of operation,
+		even if requested.
+Users:		Debugging, any userspace test suite
+
+What:		/sys/kernel/debug/scmi/<n>/transport/type
+Date:		March 2023
+KernelVersion:	6.3
+Contact:	cristian.marussi@arm.com
+Description:	A string representing the type of transport configured for this
+		SCMI instance <n>.
+Users:		Debugging, any userspace test suite
+
+What:		/sys/kernel/debug/scmi/<n>/transport/is_atomic
+Date:		March 2023
+KernelVersion:	6.3
+Contact:	cristian.marussi@arm.com
+Description:	A boolean stating if the transport configured on the underlying
+		SCMI instance <n> is capable of atomic mode of operation.
+Users:		Debugging, any userspace test suite
+
+What:		/sys/kernel/debug/scmi/<n>/transport/max_rx_timeout_ms
+Date:		March 2023
+KernelVersion:	6.3
+Contact:	cristian.marussi@arm.com
+Description:	Timeout in milliseconds allowed for SCMI synchronous replies
+		for the currently configured SCMI transport for instance <n>.
+Users:		Debugging, any userspace test suite
+
+What:		/sys/kernel/debug/scmi/<n>/transport/max_msg_size
+Date:		March 2023
+KernelVersion:	6.3
+Contact:	cristian.marussi@arm.com
+Description:	Max message size of allowed SCMI messages for the currently
+		configured SCMI transport for instance <n>.
+Users:		Debugging, any userspace test suite
+
+What:		/sys/kernel/debug/scmi/<n>/transport/tx_max_msg
+Date:		March 2023
+KernelVersion:	6.3
+Contact:	cristian.marussi@arm.com
+Description:	Max number of concurrently allowed in-flight SCMI messages for
+		the currently configured SCMI transport for instance <n> on the
+		TX channels.
+Users:		Debugging, any userspace test suite
+
+What:		/sys/kernel/debug/scmi/<n>/transport/rx_max_msg
+Date:		March 2023
+KernelVersion:	6.3
+Contact:	cristian.marussi@arm.com
+Description:	Max number of concurrently allowed in-flight SCMI messages for
+		the currently configured SCMI transport for instance <n> on the
+		RX channels.
+Users:		Debugging, any userspace test suite