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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
commitf4cdf7ca9a1fdcca413157df19753f388a5a224e (patch)
tree60a31895b2446cd7fa27514e8c2843534a0de0da /arch/arm/lib/findbit.S
downloadlinux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.tar.gz
linux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.zip
Merge tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-mediagrafted
Pull media updates from Mauro Carvalho Chehab: - v4l2-core: added ISP statistics support and per-block validation - v4l2-core: Allow unknown HDR10 white point and luminance - New camera sensors: Sony IMX678 and IMX471m, Himax HM1092 IR sensor - New codec: Milos: VPU v2.0 codec support - isp driver: gained support for Dreamchip RPPX1 ISP framework - vsp1 driver: gained support for RZ/T2H and RZ/N2H - Novalake driver: gained CVS support for new NVL hardware - dvb-core: fix feed leak on failed DMX_ADD_PID - several driver fixes, cleanups and minor improvements * tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (308 commits) media: ipu-bridge: check all DMI entries when overriding sensor rotation media: v4l2-async: avoid deleting unlinked ASC entry on link error media: rzg2l-cru: Align bytesperline to hardware DMA stride requirement media: intel/ipu6: fix async notifier cleanup leak on parse error media: staging/ipu7: fix async notifier UAF on probe error path media: amd: isp4: fix self-deadlock in isp4sd_pwron_and_init() error path media: amd: isp4: release partial allocations in isp4if_alloc_fw_gpumem() media: rcar-isp: Fix VSPX reference leaks media: rcar-isp: Release ISPCORE resources media: i2c: imx415: Release runtime PM reference on VBLANK error media: i2c: imx415: Return test pattern write errors media: renesas: vsp1: Declare index variables in for loop statement media: renesas: vsp1: Make reset control optional to support platforms without a reset line media: dt-bindings: media: renesas,vsp1: Document RZ/T2H and RZ/N2H SoCs media: dt-bindings: media: renesas,fcp: Document RZ/T2H and RZ/N2H SoCs media: nxp: imx8-isi: Add additional 32-bit RGB format support media: nxp: imx8-isi: Add 16-bit raw Bayer format support media: nxp: imx8-isi: Implement per-stream reference counting for multiplexed streams media: nxp: imx8-isi: Use BIT_ULL() for 64-bit stream masks media: nxp: imx8-isi: Correct color map between V4L2 and ISI ...
Diffstat (limited to 'arch/arm/lib/findbit.S')
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diff --git a/arch/arm/lib/findbit.S b/arch/arm/lib/findbit.S
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+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * linux/arch/arm/lib/findbit.S
+ *
+ * Copyright (C) 1995-2000 Russell King
+ *
+ * 16th March 2001 - John Ripley <jripley@sonicblue.com>
+ * Fixed so that "size" is an exclusive not an inclusive quantity.
+ * All users of these functions expect exclusive sizes, and may
+ * also call with zero size.
+ * Reworked by rmk.
+ */
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+#include <asm/unwind.h>
+ .text
+
+#ifdef __ARMEB__
+#define SWAB_ENDIAN le
+#else
+#define SWAB_ENDIAN be
+#endif
+
+ .macro find_first, endian, set, name
+ENTRY(_find_first_\name\()bit_\endian)
+ UNWIND( .fnstart)
+ teq r1, #0
+ beq 3f
+ mov r2, #0
+1: ldr r3, [r0], #4
+ .ifeq \set
+ mvns r3, r3 @ invert/test bits
+ .else
+ movs r3, r3 @ test bits
+ .endif
+ .ifc \endian, SWAB_ENDIAN
+ bne .L_found_swab
+ .else
+ bne .L_found @ found the bit?
+ .endif
+ add r2, r2, #32 @ next index
+2: cmp r2, r1 @ any more?
+ blo 1b
+3: mov r0, r1 @ no more bits
+ ret lr
+ UNWIND( .fnend)
+ENDPROC(_find_first_\name\()bit_\endian)
+ .endm
+
+ .macro find_next, endian, set, name
+ENTRY(_find_next_\name\()bit_\endian)
+ UNWIND( .fnstart)
+ cmp r2, r1
+ bhs 3b
+ mov ip, r2, lsr #5 @ word index
+ add r0, r0, ip, lsl #2
+ ands ip, r2, #31 @ bit position
+ beq 1b
+ ldr r3, [r0], #4
+ .ifeq \set
+ mvn r3, r3 @ invert bits
+ .endif
+ .ifc \endian, SWAB_ENDIAN
+ rev_l r3, ip
+ .if .Lrev_l_uses_tmp
+ @ we need to recompute ip because rev_l will have overwritten
+ @ it.
+ and ip, r2, #31 @ bit position
+ .endif
+ .endif
+ movs r3, r3, lsr ip @ shift off unused bits
+ bne .L_found
+ orr r2, r2, #31 @ no zero bits
+ add r2, r2, #1 @ align bit pointer
+ b 2b @ loop for next bit
+ UNWIND( .fnend)
+ENDPROC(_find_next_\name\()bit_\endian)
+ .endm
+
+ .macro find_bit, endian, set, name
+ find_first \endian, \set, \name
+ find_next \endian, \set, \name
+ .endm
+
+/* _find_first_zero_bit_le and _find_next_zero_bit_le */
+ find_bit le, 0, zero_
+
+/* _find_first_bit_le and _find_next_bit_le */
+ find_bit le, 1
+
+#ifdef __ARMEB__
+
+/* _find_first_zero_bit_be and _find_next_zero_bit_be */
+ find_bit be, 0, zero_
+
+/* _find_first_bit_be and _find_next_bit_be */
+ find_bit be, 1
+
+#endif
+
+/*
+ * One or more bits in the LSB of r3 are assumed to be set.
+ */
+.L_found_swab:
+ UNWIND( .fnstart)
+ rev_l r3, ip
+.L_found:
+#if __LINUX_ARM_ARCH__ >= 7
+ rbit r3, r3 @ reverse bits
+ clz r3, r3 @ count high zero bits
+ add r0, r2, r3 @ add offset of first set bit
+#elif __LINUX_ARM_ARCH__ >= 5
+ rsb r0, r3, #0
+ and r3, r3, r0 @ mask out lowest bit set
+ clz r3, r3 @ count high zero bits
+ rsb r3, r3, #31 @ offset of first set bit
+ add r0, r2, r3 @ add offset of first set bit
+#else
+ mov ip, #~0
+ tst r3, ip, lsr #16 @ test bits 0-15
+ addeq r2, r2, #16
+ moveq r3, r3, lsr #16
+ tst r3, #0x00ff
+ addeq r2, r2, #8
+ moveq r3, r3, lsr #8
+ tst r3, #0x000f
+ addeq r2, r2, #4
+ moveq r3, r3, lsr #4
+ tst r3, #0x0003
+ addeq r2, r2, #2
+ moveq r3, r3, lsr #2
+ tst r3, #0x0001
+ addeq r2, r2, #1
+ mov r0, r2
+#endif
+ cmp r1, r0 @ Clamp to maxbit
+ movlo r0, r1
+ ret lr
+ UNWIND( .fnend)