^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) /* SPDX-License-Identifier: GPL-2.0 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * Copyright (C) 2008 Michal Simek
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) * Copyright (C) 2007 John Williams
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * Copyright (C) 2006 Atmark Techno, Inc.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) #ifndef _ASM_MICROBLAZE_DELAY_H
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) #define _ASM_MICROBLAZE_DELAY_H
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/param.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) static inline void __delay(unsigned long loops)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) asm volatile ("# __delay \n\t" \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) "1: addi %0, %0, -1\t\n" \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) "bneid %0, 1b \t\n" \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) "nop \t\n"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) : "=r" (loops)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) : "0" (loops));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) * Note that 19 * 226 == 4294 ==~ 2^32 / 10^6, so
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) * loops = (4294 * usecs * loops_per_jiffy * HZ) / 2^32.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) * The mul instruction gives us loops = (a * b) / 2^32.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) * We choose a = usecs * 19 * HZ and b = loops_per_jiffy * 226
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) * because this lets us support a wide range of HZ and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) * loops_per_jiffy values without either a or b overflowing 2^32.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) * Thus we need usecs * HZ <= (2^32 - 1) / 19 = 226050910 and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) * loops_per_jiffy <= (2^32 - 1) / 226 = 19004280
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) * (which corresponds to ~3800 bogomips at HZ = 100).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) * -- paulus
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) #define __MAX_UDELAY (226050910UL/HZ) /* maximum udelay argument */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) #define __MAX_NDELAY (4294967295UL/HZ) /* maximum ndelay argument */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) extern unsigned long loops_per_jiffy;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) static inline void __udelay(unsigned int x)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) unsigned long long tmp =
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) (unsigned long long)x * (unsigned long long)loops_per_jiffy \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) * 226LL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) unsigned loops = tmp >> 32;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) __asm__("mulxuu %0,%1,%2" : "=r" (loops) :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) "r" (x), "r" (loops_per_jiffy * 226));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) __delay(loops);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) extern void __bad_udelay(void); /* deliberately undefined */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) extern void __bad_ndelay(void); /* deliberately undefined */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) #define udelay(n) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) ({ \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) if (__builtin_constant_p(n)) { \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) if ((n) / __MAX_UDELAY >= 1) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) __bad_udelay(); \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) else \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) __udelay((n) * (19 * HZ)); \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) } else { \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) __udelay((n) * (19 * HZ)); \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) } \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) })
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) #define ndelay(n) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) ({ \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) if (__builtin_constant_p(n)) { \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) if ((n) / __MAX_NDELAY >= 1) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) __bad_ndelay(); \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) else \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) __udelay((n) * HZ); \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) } else { \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) __udelay((n) * HZ); \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) } \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) })
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) #define muldiv(a, b, c) (((a)*(b))/(c))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) #endif /* _ASM_MICROBLAZE_DELAY_H */
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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