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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/xtensa/lib/modsi3.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/xtensa/lib/modsi3.S')
-rw-r--r--arch/xtensa/lib/modsi3.S88
1 files changed, 88 insertions, 0 deletions
diff --git a/arch/xtensa/lib/modsi3.S b/arch/xtensa/lib/modsi3.S
new file mode 100644
index 000000000..c5f4295c6
--- /dev/null
+++ b/arch/xtensa/lib/modsi3.S
@@ -0,0 +1,88 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later WITH GCC-exception-2.0 */
+#include <linux/linkage.h>
+#include <asm/asmmacro.h>
+#include <asm/core.h>
+
+ENTRY(__modsi3)
+
+ abi_entry_default
+#if XCHAL_HAVE_DIV32
+ rems a2, a2, a3
+#else
+ mov a7, a2 /* save original (signed) dividend */
+ do_abs a2, a2, a4 /* udividend = abs (dividend) */
+ do_abs a3, a3, a4 /* udivisor = abs (divisor) */
+ bltui a3, 2, .Lle_one /* check if udivisor <= 1 */
+ do_nsau a5, a2, a6, a8 /* udividend_shift = nsau (udividend) */
+ do_nsau a4, a3, a6, a8 /* udivisor_shift = nsau (udivisor) */
+ bgeu a5, a4, .Lspecial
+
+ sub a4, a4, a5 /* count = udivisor_shift - udividend_shift */
+ ssl a4
+ sll a3, a3 /* udivisor <<= count */
+
+ /* test-subtract-and-shift loop */
+#if XCHAL_HAVE_LOOPS
+ loopnez a4, .Lloopend
+#endif /* XCHAL_HAVE_LOOPS */
+.Lloop:
+ bltu a2, a3, .Lzerobit
+ sub a2, a2, a3
+.Lzerobit:
+ srli a3, a3, 1
+#if !XCHAL_HAVE_LOOPS
+ addi a4, a4, -1
+ bnez a4, .Lloop
+#endif /* !XCHAL_HAVE_LOOPS */
+.Lloopend:
+
+.Lspecial:
+ bltu a2, a3, .Lreturn
+ sub a2, a2, a3 /* subtract again if udividend >= udivisor */
+.Lreturn:
+ bgez a7, .Lpositive
+ neg a2, a2 /* if (dividend < 0), return -udividend */
+.Lpositive:
+ abi_ret_default
+
+.Lle_one:
+ bnez a3, .Lreturn0
+
+ /* Divide by zero: Use an illegal instruction to force an exception.
+ The subsequent "DIV0" string can be recognized by the exception
+ handler to identify the real cause of the exception. */
+ ill
+ .ascii "DIV0"
+
+.Lreturn0:
+ movi a2, 0
+#endif /* XCHAL_HAVE_DIV32 */
+ abi_ret_default
+
+ENDPROC(__modsi3)
+EXPORT_SYMBOL(__modsi3)
+
+#if !XCHAL_HAVE_NSA
+ .section .rodata
+ .align 4
+ .global __nsau_data
+ .type __nsau_data, @object
+__nsau_data:
+ .byte 8, 7, 6, 6, 5, 5, 5, 5, 4, 4, 4, 4, 4, 4, 4, 4
+ .byte 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3
+ .byte 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2
+ .byte 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2
+ .byte 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1
+ .byte 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1
+ .byte 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1
+ .byte 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1
+ .byte 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
+ .byte 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
+ .byte 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
+ .byte 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
+ .byte 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
+ .byte 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
+ .byte 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
+ .byte 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
+ .size __nsau_data, . - __nsau_data
+#endif /* !XCHAL_HAVE_NSA */