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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/alpha/lib/memcpy.c
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/alpha/lib/memcpy.c')
-rw-r--r--arch/alpha/lib/memcpy.c166
1 files changed, 166 insertions, 0 deletions
diff --git a/arch/alpha/lib/memcpy.c b/arch/alpha/lib/memcpy.c
new file mode 100644
index 000000000..78b6850a9
--- /dev/null
+++ b/arch/alpha/lib/memcpy.c
@@ -0,0 +1,166 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * linux/arch/alpha/lib/memcpy.c
+ *
+ * Copyright (C) 1995 Linus Torvalds
+ */
+
+/*
+ * This is a reasonably optimized memcpy() routine.
+ */
+
+/*
+ * Note that the C code is written to be optimized into good assembly. However,
+ * at this point gcc is unable to sanely compile "if (n >= 0)", resulting in a
+ * explicit compare against 0 (instead of just using the proper "blt reg, xx" or
+ * "bge reg, xx"). I hope alpha-gcc will be fixed to notice this eventually..
+ */
+
+#include <linux/types.h>
+#include <linux/export.h>
+#include <linux/string.h>
+
+/*
+ * This should be done in one go with ldq_u*2/mask/stq_u. Do it
+ * with a macro so that we can fix it up later..
+ */
+#define ALIGN_DEST_TO8_UP(d,s,n) \
+ while (d & 7) { \
+ if (n <= 0) return; \
+ n--; \
+ *(char *) d = *(char *) s; \
+ d++; s++; \
+ }
+#define ALIGN_DEST_TO8_DN(d,s,n) \
+ while (d & 7) { \
+ if (n <= 0) return; \
+ n--; \
+ d--; s--; \
+ *(char *) d = *(char *) s; \
+ }
+
+/*
+ * This should similarly be done with ldq_u*2/mask/stq. The destination
+ * is aligned, but we don't fill in a full quad-word
+ */
+#define DO_REST_UP(d,s,n) \
+ while (n > 0) { \
+ n--; \
+ *(char *) d = *(char *) s; \
+ d++; s++; \
+ }
+#define DO_REST_DN(d,s,n) \
+ while (n > 0) { \
+ n--; \
+ d--; s--; \
+ *(char *) d = *(char *) s; \
+ }
+
+/*
+ * This should be done with ldq/mask/stq. The source and destination are
+ * aligned, but we don't fill in a full quad-word
+ */
+#define DO_REST_ALIGNED_UP(d,s,n) DO_REST_UP(d,s,n)
+#define DO_REST_ALIGNED_DN(d,s,n) DO_REST_DN(d,s,n)
+
+/*
+ * This does unaligned memory copies. We want to avoid storing to
+ * an unaligned address, as that would do a read-modify-write cycle.
+ * We also want to avoid double-reading the unaligned reads.
+ *
+ * Note the ordering to try to avoid load (and address generation) latencies.
+ */
+static inline void __memcpy_unaligned_up (unsigned long d, unsigned long s,
+ long n)
+{
+ ALIGN_DEST_TO8_UP(d,s,n);
+ n -= 8; /* to avoid compare against 8 in the loop */
+ if (n >= 0) {
+ unsigned long low_word, high_word;
+ __asm__("ldq_u %0,%1":"=r" (low_word):"m" (*(unsigned long *) s));
+ do {
+ unsigned long tmp;
+ __asm__("ldq_u %0,%1":"=r" (high_word):"m" (*(unsigned long *)(s+8)));
+ n -= 8;
+ __asm__("extql %1,%2,%0"
+ :"=r" (low_word)
+ :"r" (low_word), "r" (s));
+ __asm__("extqh %1,%2,%0"
+ :"=r" (tmp)
+ :"r" (high_word), "r" (s));
+ s += 8;
+ *(unsigned long *) d = low_word | tmp;
+ d += 8;
+ low_word = high_word;
+ } while (n >= 0);
+ }
+ n += 8;
+ DO_REST_UP(d,s,n);
+}
+
+static inline void __memcpy_unaligned_dn (unsigned long d, unsigned long s,
+ long n)
+{
+ /* I don't understand AXP assembler well enough for this. -Tim */
+ s += n;
+ d += n;
+ while (n--)
+ * (char *) --d = * (char *) --s;
+}
+
+/*
+ * Hmm.. Strange. The __asm__ here is there to make gcc use an integer register
+ * for the load-store. I don't know why, but it would seem that using a floating
+ * point register for the move seems to slow things down (very small difference,
+ * though).
+ *
+ * Note the ordering to try to avoid load (and address generation) latencies.
+ */
+static inline void __memcpy_aligned_up (unsigned long d, unsigned long s,
+ long n)
+{
+ ALIGN_DEST_TO8_UP(d,s,n);
+ n -= 8;
+ while (n >= 0) {
+ unsigned long tmp;
+ __asm__("ldq %0,%1":"=r" (tmp):"m" (*(unsigned long *) s));
+ n -= 8;
+ s += 8;
+ *(unsigned long *) d = tmp;
+ d += 8;
+ }
+ n += 8;
+ DO_REST_ALIGNED_UP(d,s,n);
+}
+static inline void __memcpy_aligned_dn (unsigned long d, unsigned long s,
+ long n)
+{
+ s += n;
+ d += n;
+ ALIGN_DEST_TO8_DN(d,s,n);
+ n -= 8;
+ while (n >= 0) {
+ unsigned long tmp;
+ s -= 8;
+ __asm__("ldq %0,%1":"=r" (tmp):"m" (*(unsigned long *) s));
+ n -= 8;
+ d -= 8;
+ *(unsigned long *) d = tmp;
+ }
+ n += 8;
+ DO_REST_ALIGNED_DN(d,s,n);
+}
+
+#undef memcpy
+
+void * memcpy(void * dest, const void *src, size_t n)
+{
+ if (!(((unsigned long) dest ^ (unsigned long) src) & 7)) {
+ __memcpy_aligned_up ((unsigned long) dest, (unsigned long) src,
+ n);
+ return dest;
+ }
+ __memcpy_unaligned_up ((unsigned long) dest, (unsigned long) src, n);
+ return dest;
+}
+EXPORT_SYMBOL(memcpy);