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authorLinus Torvalds <torvalds@linux-foundation.org>2026-09-05 11:59:05 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-09-05 11:59:05 -0700
commit9f0346dcbea363787186c94ef94dd01aaa215afa (patch)
treeb81c168f4d0dbe4c7f4750f4598d48a6deb72094 /arch/sh/lib/delay.c
downloadlinux-stable-9f0346dcbea363787186c94ef94dd01aaa215afa.tar.gz
linux-stable-9f0346dcbea363787186c94ef94dd01aaa215afa.zip
Merge tag 'driver-core-7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-coregrafted
Pull driver core fixes from Danilo Krummrich: - Fix kernfs listxattr() not returning security xattr names (e.g. SELinux labels) when the kernfs node has no allocated kernfs_iattrs - Fix silent truncation of IRQ vector indices in the Rust PCI abstractions - Don't select OF from DRIVER_PE_KUNIT_TEST; skip the test when OF is disabled instead of silently enabling extra kernel functionality - Russ Weight is retiring from kernel development; update the Firmware Loader sysfs contact to the driver-core mailing list, add a CREDITS entry for Firmware Upload, and update MAINTAINERS accordingly * tag 'driver-core-7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core: MAINTAINERS: Remove Russ Weight from Firmware Loader CREDITS: Add CREDITS entry for Firmware Upload firmware_loader: Change contact for sysfs nodes rust: pci: reject IRQ vector indices that do not fit in u32 kernfs: preserve security xattrs without allocating iattrs drivers: base: test: DRIVER_PE_KUNIT_TEST should not select OF
Diffstat (limited to 'arch/sh/lib/delay.c')
-rw-r--r--arch/sh/lib/delay.c54
1 files changed, 54 insertions, 0 deletions
diff --git a/arch/sh/lib/delay.c b/arch/sh/lib/delay.c
new file mode 100644
index 000000000..dad8e6a54
--- /dev/null
+++ b/arch/sh/lib/delay.c
@@ -0,0 +1,54 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Precise Delay Loops for SuperH
+ *
+ * Copyright (C) 1999 Niibe Yutaka & Kaz Kojima
+ */
+
+#include <linux/sched.h>
+#include <linux/delay.h>
+
+void __delay(unsigned long loops)
+{
+ __asm__ __volatile__(
+ /*
+ * ST40-300 appears to have an issue with this code,
+ * normally taking two cycles each loop, as with all
+ * other SH variants. If however the branch and the
+ * delay slot straddle an 8 byte boundary, this increases
+ * to 3 cycles.
+ * This align directive ensures this doesn't occur.
+ */
+ ".balign 8\n\t"
+
+ "tst %0, %0\n\t"
+ "1:\t"
+ "bf/s 1b\n\t"
+ " dt %0"
+ : "=r" (loops)
+ : "0" (loops)
+ : "t");
+}
+
+inline void __const_udelay(unsigned long xloops)
+{
+ xloops *= 4;
+ __asm__("dmulu.l %0, %2\n\t"
+ "sts mach, %0"
+ : "=r" (xloops)
+ : "0" (xloops),
+ "r" (cpu_data[raw_smp_processor_id()].loops_per_jiffy * (HZ/4))
+ : "macl", "mach");
+ __delay(++xloops);
+}
+
+void __udelay(unsigned long usecs)
+{
+ __const_udelay(usecs * 0x000010c6); /* 2**32 / 1000000 */
+}
+
+void __ndelay(unsigned long nsecs)
+{
+ __const_udelay(nsecs * 0x00000005);
+}
+