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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-24 08:46:03 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-24 08:46:03 -0700
commitcf9610f9116d55c5a66ef9f1faecacabd93a9322 (patch)
tree757a3d280760c654767631cab5ad8af2d86d1848 /arch/riscv/lib/strcmp.S
downloadlinux-stable-cf9610f9116d55c5a66ef9f1faecacabd93a9322.tar.gz
linux-stable-cf9610f9116d55c5a66ef9f1faecacabd93a9322.zip
Merge tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrlgrafted
Pull pin control updates from Linus Walleij: "Core changes: - Use the non-blocking mux_state_try_select() in the generic MUX pin control back-end - Free pin maps on pinctrl_generic_to_map() failure in the core helpers New hardware pin control: - Qualcomm Maili TLMM SoC, PMG1110 PMIC, and Eliza LPASS LPI TLMM SoC (this is for the low power audio, LPASS = Low Power Audio SubSystem portions) - Upboard support on top of the Intel pin controller - Apple T6030 and T6031 support (just compatible strings) - Samsung Exynos 8855 SoC - Mediatek MT6858 SoC - Rockchip RK3308B and RV1106 SoCs - Airoha EN7523 and AN7563 SoCs Improvements: - Qualcomm TLMM GPIOs are unconditionally marked as wakeup capable - Qualcomm improvements on top of the Qualcomm PDC (power domain controller) irqchip improvements from tglx:s tree - Qualcomm IPQ806x and IPQ9650 non-urgent pin grop fixups - The NPCM8xx driver has been put into shape fixing many pin and group definitions - Some non-urgent Tegra 264 pin assignments are fixed up - Some non-urgent fixups to Airoha AN7581 and AN7583 registers and pin assignments, missing features etc" * tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (130 commits) dt-bindings: pinctrl: Convert TI DA850 pupd to DT schema pinctrl: meson: sync some modify from A4 pinctrl: meson: a4: Add input enable pin configuration pinctrl: realtek: rtd1625: remove unused group name spdif_sel pinctrl: realtek: rtd1625: fix base_bit for VE4 GPIO 13 dt-bindings: pinctrl: microchip,pic32mzda-pinctrl: Convert to DT schema Revert "Merge branch 'ib-rsk7204' into devel" pinctrl: rockchip: Add RV1106 pinctrl support dt-bindings: pinctrl: rockchip: Add RV1106 compatible pinctrl: rockchip: Decode drive strength in the get function pinctrl: fix PINCTRL_GENERIC_MUX not always being selectable pinctrl: airoha: add support of an7563 SoC dt-bindings: pinctrl: airoha: add support of an7563 pin controller pinctrl: airoha: try to find chip scu node by phandle first pinctrl: airoha: add support of en7523 SoC dt-bindings: pinctrl: airoha: add support of en7523 pin controller pinctrl: airoha: an7583: add support for olt pinmux pinctrl: airoha: an7583: add support for pon_alt pinmux pinctrl: airoha: an7583: add support for npu_uart pinmux dt-bindings: pinctrl: airoha: an7583: add missed features ...
Diffstat (limited to 'arch/riscv/lib/strcmp.S')
-rw-r--r--arch/riscv/lib/strcmp.S125
1 files changed, 125 insertions, 0 deletions
diff --git a/arch/riscv/lib/strcmp.S b/arch/riscv/lib/strcmp.S
new file mode 100644
index 000000000..65027e742
--- /dev/null
+++ b/arch/riscv/lib/strcmp.S
@@ -0,0 +1,125 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <linux/linkage.h>
+#include <asm/asm.h>
+#include <asm/alternative-macros.h>
+#include <asm/hwcap.h>
+
+/* int strcmp(const char *cs, const char *ct) */
+SYM_FUNC_START(strcmp)
+
+ __ALTERNATIVE_CFG("nop", "j strcmp_zbb", 0, RISCV_ISA_EXT_ZBB,
+ IS_ENABLED(CONFIG_RISCV_ISA_ZBB) && IS_ENABLED(CONFIG_TOOLCHAIN_HAS_ZBB))
+
+ /*
+ * Returns
+ * a0 - comparison result, value like strcmp
+ *
+ * Parameters
+ * a0 - string1
+ * a1 - string2
+ *
+ * Clobbers
+ * t0, t1
+ */
+1:
+ lbu t0, 0(a0)
+ lbu t1, 0(a1)
+ addi a0, a0, 1
+ addi a1, a1, 1
+ bne t0, t1, 2f
+ bnez t0, 1b
+ li a0, 0
+ ret
+2:
+ /*
+ * strcmp only needs to return (< 0, 0, > 0) values
+ * not necessarily -1, 0, +1
+ */
+ sub a0, t0, t1
+ ret
+
+/*
+ * Variant of strcmp using the ZBB extension if available.
+ * The code was published as part of the bitmanip manual
+ * in Appendix A.
+ */
+#if defined(CONFIG_RISCV_ISA_ZBB) && defined(CONFIG_TOOLCHAIN_HAS_ZBB)
+strcmp_zbb:
+
+.option push
+.option arch,+zbb
+
+ /*
+ * Returns
+ * a0 - comparison result, value like strcmp
+ *
+ * Parameters
+ * a0 - string1
+ * a1 - string2
+ *
+ * Clobbers
+ * t0, t1, t2, t3, t4
+ */
+
+ or t2, a0, a1
+ li t4, -1
+ and t2, t2, SZREG-1
+ bnez t2, 3f
+
+ /* Main loop for aligned string. */
+ .p2align 3
+1:
+ REG_L t0, 0(a0)
+ REG_L t1, 0(a1)
+ orc.b t3, t0
+ bne t3, t4, 2f
+ addi a0, a0, SZREG
+ addi a1, a1, SZREG
+ beq t0, t1, 1b
+
+ /*
+ * Words don't match, and no null byte in the first
+ * word. Get bytes in big-endian order and compare.
+ */
+#ifndef CONFIG_CPU_BIG_ENDIAN
+ rev8 t0, t0
+ rev8 t1, t1
+#endif
+
+ /* Synthesize (t0 >= t1) ? 1 : -1 in a branchless sequence. */
+ sltu a0, t0, t1
+ neg a0, a0
+ ori a0, a0, 1
+ ret
+
+2:
+ /*
+ * Found a null byte.
+ * If words don't match, fall back to simple loop.
+ */
+ bne t0, t1, 3f
+
+ /* Otherwise, strings are equal. */
+ li a0, 0
+ ret
+
+ /* Simple loop for misaligned strings. */
+ .p2align 3
+3:
+ lbu t0, 0(a0)
+ lbu t1, 0(a1)
+ addi a0, a0, 1
+ addi a1, a1, 1
+ bne t0, t1, 4f
+ bnez t0, 3b
+
+4:
+ sub a0, t0, t1
+ ret
+
+.option pop
+#endif
+SYM_FUNC_END(strcmp)
+SYM_FUNC_ALIAS(__pi_strcmp, strcmp)
+EXPORT_SYMBOL(strcmp)