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Revision 750a7eee7395492960a7aeb3a3a1aa74158ec326 authored by Paul Mundt on 11 November 2011, 06:41:50 UTC, committed by Paul Mundt on 11 November 2011, 06:41:50 UTC 
drivers: sh: Generalize runtime PM platform stub.
 
The runtime PM platform support stub in use by ARM-based SH/R-Mobile
platforms contains nothing that's specifically ARM-related and instead of
wholly generic to anything using the clock framework.

The recent runtime PM changes interact rather badly with the lazy
disabling of clocks late in the boot process through the clock framework,
leading to situations where the runtime suspend/resume paths are entered
without a clock being actively driven due to having been lazily gated
off.

In order to correct this we can trivially tie in the aforementioned stub
as a general fallback for all SH platforms that don't presently have
their own runtime PM implementations (the corner case being SH-based
SH-Mobile platforms, which have their own stub through the hwblk API --
which in turn has bitrotted and will be subsequently adapted to use the
same stub as everyone else), regardless of whether the platforms choose
to define power domains of their own or not.

This fixes up regressions for clock framework users who also build in
runtime PM support without any specific power domains of their own, which
was previously causing the serial console to be lost when warring with
lazy clock disabling.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
1 parent 5e442a4
Raw File
find_last_bit.c 
/* find_last_bit.c: fallback find next bit implementation
 *
 * Copyright (C) 2008 IBM Corporation
 * Written by Rusty Russell <rusty@rustcorp.com.au>
 * (Inspired by David Howell's find_next_bit implementation)
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version
 * 2 of the License, or (at your option) any later version.
 */

#include <linux/bitops.h>
#include <linux/module.h>
#include <asm/types.h>
#include <asm/byteorder.h>

#ifndef find_last_bit

unsigned long find_last_bit(const unsigned long *addr, unsigned long size)
{
	unsigned long words;
	unsigned long tmp;

	/* Start at final word. */
	words = size / BITS_PER_LONG;

	/* Partial final word? */
	if (size & (BITS_PER_LONG-1)) {
		tmp = (addr[words] & (~0UL >> (BITS_PER_LONG
					 - (size & (BITS_PER_LONG-1)))));
		if (tmp)
			goto found;
	}

	while (words) {
		tmp = addr[--words];
		if (tmp) {
found:
			return words * BITS_PER_LONG + __fls(tmp);
		}
	}

	/* Not found */
	return size;
}
EXPORT_SYMBOL(find_last_bit);

#endif
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