summaryrefslogtreecommitdiffstats
path: root/arch/xtensa/lib/modsi3.S
diff options
context:
space:
mode:
authorNiklas Cassel <cassel@kernel.org>2026-09-16 15:00:32 +0200
committerNiklas Cassel <cassel@kernel.org>2026-09-16 16:18:00 +0200
commit8d836581f9b1f57ceaa2b47654754ef1260b410b (patch)
tree1dbd4d0dfb99c2e238356cbe947e5b0be3e3a571 /arch/xtensa/lib/modsi3.S
downloadlinux-stable-8d836581f9b1f57ceaa2b47654754ef1260b410b.tar.gz
linux-stable-8d836581f9b1f57ceaa2b47654754ef1260b410b.zip
ata: libata-scsi: fix ata_dsm_trim_pages() kernel-docgrafted
make htmldocs fails with: Documentation/driver-api/libata:604: ./drivers/ata/libata-scsi.c:2301: ERROR: Unexpected indentation. [docutils] The Return: section of ata_dsm_trim_pages() ends its first sentence with a colon and continues with an indented bullet list. reStructuredText requires a blank line before an indented block, so docutils chokes on the list. Simply adding the missing blank line does not work either: Return: is a kernel-doc "special section", which is terminated by the first blank line, so the bullet list would end up in the Description section, detached from the sentence introducing it. Spell the two bounds out as prose instead, so that the Return: section stays self-contained. Documentation-only change. Fixes: e64e6b5dc867 ("ata: libata-scsi: scale DSM TRIM payload by MAX PAGES PER DSM COMMAND") Reported-by: Thomas Huth <thuth@redhat.com> Closes: https://lore.kernel.org/linux-ide/b0a0b8e8-cc4f-4c7b-8bc5-fee0712d405a@redhat.com/ Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Thomas Huth <thuth@redhat.com> Link: https://lore.kernel.org/r/20260916130031.29990-2-cassel@kernel.org Signed-off-by: Niklas Cassel <cassel@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 */