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authorDanilo Krummrich <dakr@kernel.org>2026-08-13 18:52:04 +0200
committerDanilo Krummrich <dakr@kernel.org>2026-08-17 01:41:36 +0200
commitf146c7bc85a51f95c05e0f8173d484eb301ece78 (patch)
tree07296ae54ed6551492b0c609dc0f5463f61f89ca /arch/powerpc/boot/util.S
downloadlinux-stable-f146c7bc85a51f95c05e0f8173d484eb301ece78.tar.gz
linux-stable-f146c7bc85a51f95c05e0f8173d484eb301ece78.zip
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>
Diffstat (limited to 'arch/powerpc/boot/util.S')
-rw-r--r--arch/powerpc/boot/util.S67
1 files changed, 67 insertions, 0 deletions
diff --git a/arch/powerpc/boot/util.S b/arch/powerpc/boot/util.S
new file mode 100644
index 000000000..6a92376da
--- /dev/null
+++ b/arch/powerpc/boot/util.S
@@ -0,0 +1,67 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copied from <file:arch/powerpc/kernel/misc_32.S>
+ *
+ * This file contains miscellaneous low-level functions.
+ * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
+ *
+ * Largely rewritten by Cort Dougan (cort@cs.nmt.edu)
+ * and Paul Mackerras.
+ *
+ * kexec bits:
+ * Copyright (C) 2002-2003 Eric Biederman <ebiederm@xmission.com>
+ * GameCube/ppc32 port Copyright (C) 2004 Albert Herranz
+ */
+#include "ppc_asm.h"
+
+#define SPRN_PVR 0x11F /* Processor Version Register */
+
+ .text
+
+/* udelay needs to know the period of the
+ * timebase in nanoseconds. This used to be hardcoded to be 60ns
+ * (period of 66MHz/4). Now a variable is used that is initialized to
+ * 60 for backward compatibility, but it can be overridden as necessary
+ * with code something like this:
+ * extern unsigned long timebase_period_ns;
+ * timebase_period_ns = 1000000000 / bd->bi_tbfreq;
+ */
+ .data
+ .globl timebase_period_ns
+timebase_period_ns:
+ .long 60
+
+ .text
+/*
+ * Delay for a number of microseconds
+ */
+ .globl udelay
+udelay:
+ mulli r4,r3,1000 /* nanoseconds */
+ /* Change r4 to be the number of ticks using:
+ * (nanoseconds + (timebase_period_ns - 1 )) / timebase_period_ns
+ * timebase_period_ns defaults to 60 (16.6MHz) */
+ mflr r5
+ bcl 20,31,0f
+0: mflr r6
+ mtlr r5
+ addis r5,r6,(timebase_period_ns-0b)@ha
+ lwz r5,(timebase_period_ns-0b)@l(r5)
+ add r4,r4,r5
+ addi r4,r4,-1
+ divw r4,r4,r5 /* BUS ticks */
+1: MFTBU(r5)
+ MFTBL(r6)
+ MFTBU(r7)
+ cmpw 0,r5,r7
+ bne 1b /* Get [synced] base time */
+ addc r9,r6,r4 /* Compute end time */
+ addze r8,r5
+2: MFTBU(r5)
+ cmpw 0,r5,r8
+ blt 2b
+ bgt 3f
+ MFTBL(r6)
+ cmpw 0,r6,r9
+ blt 2b
+3: blr