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The current implementations of __ndelay and __udelay call a hypervisor service to delay, but the hypervisor service isn't actually implemented very well, and the consensus is that Linux should handle figuring this out natively and not use a hypervisor service. By converting nanoseconds to cycles, and then spinning until the cycle counter reaches the desired cycle, we get several benefits: first, we are sensitive to the actual clock speed; second, we use less power by issuing a slow SPR read once every six cycles while we delay; and third, we properly handle the case of an interrupt by exiting at the target time rather than after some number of cycles. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com> |
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| .. | ||
| atomic_32.c | ||
| atomic_asm_32.S | ||
| cacheflush.c | ||
| checksum.c | ||
| cpumask.c | ||
| delay.c | ||
| exports.c | ||
| Makefile | ||
| mb_incoherent.S | ||
| memchr_32.c | ||
| memcpy_32.S | ||
| memcpy_tile64.c | ||
| memmove.c | ||
| memset_32.c | ||
| spinlock_32.c | ||
| spinlock_common.h | ||
| strchr_32.c | ||
| strlen_32.c | ||
| uaccess.c | ||
| usercopy_32.S | ||