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, 87 insertions, 0 deletions

diff --git a/arch/powerpc/boot/simpleboot.c b/arch/powerpc/boot/simpleboot.c
new file mode 100644
index 000000000..27591df41
--- /dev/null
+++ b/arch/powerpc/boot/simpleboot.c
@@ -0,0 +1,87 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * The simple platform -- for booting when firmware doesn't supply a device
+ *                        tree or any platform configuration information.
+ *                        All data is extracted from an embedded device tree
+ *                        blob.
+ *
+ * Authors: Scott Wood <scottwood@freescale.com>
+ *          Grant Likely <grant.likely@secretlab.ca>
+ *
+ * Copyright (c) 2007 Freescale Semiconductor, Inc.
+ * Copyright (c) 2008 Secret Lab Technologies Ltd.
+ */
+
+#include "ops.h"
+#include "types.h"
+#include "io.h"
+#include "stdio.h"
+#include <libfdt.h>
+
+BSS_STACK(4*1024);
+
+extern int platform_specific_init(void) __attribute__((weak));
+
+void platform_init(unsigned long r3, unsigned long r4, unsigned long r5,
+		   unsigned long r6, unsigned long r7)
+{
+	const u32 *na, *ns, *reg, *timebase;
+	u64 memsize64;
+	int node, size, i;
+
+	/* Make sure FDT blob is sane */
+	if (fdt_check_header(_dtb_start) != 0)
+		fatal("Invalid device tree blob\n");
+
+	/* Find the #address-cells and #size-cells properties */
+	node = fdt_path_offset(_dtb_start, "/");
+	if (node < 0)
+		fatal("Cannot find root node\n");
+	na = fdt_getprop(_dtb_start, node, "#address-cells", &size);
+	if (!na || (size != 4))
+		fatal("Cannot find #address-cells property");
+	ns = fdt_getprop(_dtb_start, node, "#size-cells", &size);
+	if (!ns || (size != 4))
+		fatal("Cannot find #size-cells property");
+
+	/* Find the memory range */
+	node = fdt_node_offset_by_prop_value(_dtb_start, -1, "device_type",
+					     "memory", sizeof("memory"));
+	if (node < 0)
+		fatal("Cannot find memory node\n");
+	reg = fdt_getprop(_dtb_start, node, "reg", &size);
+	if (size < (*na+*ns) * sizeof(u32))
+		fatal("cannot get memory range\n");
+
+	/* Only interested in memory based at 0 */
+	for (i = 0; i < *na; i++)
+		if (*reg++ != 0)
+			fatal("Memory range is not based at address 0\n");
+
+	/* get the memsize and truncate it to under 4G on 32 bit machines */
+	memsize64 = 0;
+	for (i = 0; i < *ns; i++)
+		memsize64 = (memsize64 << 32) | *reg++;
+	if (sizeof(void *) == 4 && memsize64 >= 0x100000000ULL)
+		memsize64 = 0xffffffff;
+
+	/* finally, setup the timebase */
+	node = fdt_node_offset_by_prop_value(_dtb_start, -1, "device_type",
+					     "cpu", sizeof("cpu"));
+	if (node < 0)
+		fatal("Cannot find cpu node\n");
+	timebase = fdt_getprop(_dtb_start, node, "timebase-frequency", &size);
+	if (timebase && (size == 4))
+		timebase_period_ns = 1000000000 / *timebase;
+
+	/* Now we have the memory size; initialize the heap */
+	simple_alloc_init(_end, memsize64 - (unsigned long)_end, 32, 64);
+
+	/* prepare the device tree and find the console */
+	fdt_init(_dtb_start);
+
+	if (platform_specific_init)
+		platform_specific_init();
+
+	serial_console_init();
+}