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authorDave Airlie <airlied@redhat.com>2026-09-26 07:57:59 +1000
committerDave Airlie <airlied@redhat.com>2026-09-26 07:58:24 +1000
commita9ed3aa9b87ee41e8ab3ff471b1331c154767e45 (patch)
treecc62d74e0eb4905246978674461e78e2f9df2afd /arch/arm/lib/delay-loop.S
downloadlinux-stable-a9ed3aa9b87ee41e8ab3ff471b1331c154767e45.tar.gz
linux-stable-a9ed3aa9b87ee41e8ab3ff471b1331c154767e45.zip
Merge tag 'drm-misc-fixes-2026-09-24' of https://gitlab.freedesktop.org/drm/misc/kernel into drm-fixesgrafted
A number of fixes: - bridge: - samsung-dsim: fix GPIO lifetime - client: Null pointer dereference fix - imagination: error handling fix, page handling fix - nouveau: fix reference leaks, double-frees, out-of-bounds accesses, use-after-frees, don't reject config without SCDC, a number of workarounds - virtio: fix memory leak, reference leaks, null pointer dereference, add pixel blend mode, cache coherency fix Signed-off-by: Dave Airlie <airlied@redhat.com> From: Maxime Ripard <self@mripard.dev> Link: https://patch.msgid.link/arU22zzqUGDEco1y@houat
Diffstat (limited to 'arch/arm/lib/delay-loop.S')
-rw-r--r--arch/arm/lib/delay-loop.S67
1 files changed, 67 insertions, 0 deletions
diff --git a/arch/arm/lib/delay-loop.S b/arch/arm/lib/delay-loop.S
new file mode 100644
index 000000000..33b08ca1c
--- /dev/null
+++ b/arch/arm/lib/delay-loop.S
@@ -0,0 +1,67 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * linux/arch/arm/lib/delay.S
+ *
+ * Copyright (C) 1995, 1996 Russell King
+ */
+#include <linux/linkage.h>
+#include <linux/cfi_types.h>
+#include <asm/assembler.h>
+#include <asm/delay.h>
+
+#ifdef CONFIG_ARCH_RPC
+ .arch armv4
+#endif
+
+ .text
+
+.LC0: .word loops_per_jiffy
+.LC1: .word UDELAY_MULT
+
+/*
+ * loops = r0 * HZ * loops_per_jiffy / 1000000
+ *
+ * r0 <= 2000
+ * HZ <= 1000
+ */
+
+SYM_TYPED_FUNC_START(__loop_udelay)
+ ldr r2, .LC1
+ mul r0, r2, r0 @ r0 = delay_us * UDELAY_MULT
+ b __loop_const_udelay
+SYM_FUNC_END(__loop_udelay)
+
+SYM_TYPED_FUNC_START(__loop_const_udelay) @ 0 <= r0 <= 0xfffffaf0
+ ldr r2, .LC0
+ ldr r2, [r2]
+ umull r1, r0, r2, r0 @ r0-r1 = r0 * loops_per_jiffy
+ adds r1, r1, #0xffffffff @ rounding up ...
+ adcs r0, r0, r0 @ and right shift by 31
+ reteq lr
+ b __loop_delay
+SYM_FUNC_END(__loop_const_udelay)
+
+ .align 3
+
+@ Delay routine
+SYM_TYPED_FUNC_START(__loop_delay)
+ subs r0, r0, #1
+#if 0
+ retls lr
+ subs r0, r0, #1
+ retls lr
+ subs r0, r0, #1
+ retls lr
+ subs r0, r0, #1
+ retls lr
+ subs r0, r0, #1
+ retls lr
+ subs r0, r0, #1
+ retls lr
+ subs r0, r0, #1
+ retls lr
+ subs r0, r0, #1
+#endif
+ bhi __loop_delay
+ ret lr
+SYM_FUNC_END(__loop_delay)