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authorYijie Yang <yijie.yang@oss.qualcomm.com>2026-08-11 16:46:47 +0800
committerRob Herring (Arm) <robh@kernel.org>2026-08-15 15:46:52 -0500
commite1c13aed4a1641550e8c9518c96f016e1d52d09b (patch)
tree61c2297688373db165cc857b7c7adcb147a5c419 /arch/alpha/lib/strlen.S
downloadlinux-stable-e1c13aed4a1641550e8c9518c96f016e1d52d09b.tar.gz
linux-stable-e1c13aed4a1641550e8c9518c96f016e1d52d09b.zip
dt-bindings: interconnect: qcom-bwmon: Add Maili cpu-bwmon compatiblegrafted
Add the Qualcomm Maili SoC compatible string for the CPU bandwidth monitor (BWMONv4). This falls back to the sdm845-bwmon compatible, consistent with the existing pattern used by other recent SoCs such as sm8750 and kaanapali. Signed-off-by: Yijie Yang <yijie.yang@oss.qualcomm.com> Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com> Reviewed-by: Jingyi Wang <jingyi.wang@oss.qualcomm.com> Link: https://patch.msgid.link/20260811-bwmon-v2-1-80f7f150ab9e@oss.qualcomm.com Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
Diffstat (limited to 'arch/alpha/lib/strlen.S')
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diff --git a/arch/alpha/lib/strlen.S b/arch/alpha/lib/strlen.S
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+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * strlen.S (c) 1995 David Mosberger (davidm@cs.arizona.edu)
+ *
+ * Finds length of a 0-terminated string. Optimized for the
+ * Alpha architecture:
+ *
+ * - memory accessed as aligned quadwords only
+ * - uses bcmpge to compare 8 bytes in parallel
+ * - does binary search to find 0 byte in last
+ * quadword (HAKMEM needed 12 instructions to
+ * do this instead of the 9 instructions that
+ * binary search needs).
+ */
+#include <linux/export.h>
+ .set noreorder
+ .set noat
+
+ .align 3
+
+ .globl strlen
+ .ent strlen
+
+strlen:
+ ldq_u $1, 0($16) # load first quadword ($16 may be misaligned)
+ lda $2, -1($31)
+ insqh $2, $16, $2
+ andnot $16, 7, $0
+ or $2, $1, $1
+ cmpbge $31, $1, $2 # $2 <- bitmask: bit i == 1 <==> i-th byte == 0
+ bne $2, found
+
+loop: ldq $1, 8($0)
+ addq $0, 8, $0 # addr += 8
+ nop # helps dual issue last two insns
+ cmpbge $31, $1, $2
+ beq $2, loop
+
+found: blbs $2, done # make aligned case fast
+ negq $2, $3
+ and $2, $3, $2
+
+ and $2, 0x0f, $1
+ addq $0, 4, $3
+ cmoveq $1, $3, $0
+
+ and $2, 0x33, $1
+ addq $0, 2, $3
+ cmoveq $1, $3, $0
+
+ and $2, 0x55, $1
+ addq $0, 1, $3
+ cmoveq $1, $3, $0
+
+done: subq $0, $16, $0
+ ret $31, ($26)
+
+ .end strlen
+ EXPORT_SYMBOL(strlen)