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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /arch/sh/lib/delay.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/sh/lib/delay.c')
-rw-r--r-- | arch/sh/lib/delay.c | 54 |
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); +} + |