linux-stable/arch/mips/kernel/csrc-gic.c
Steven J. Hill dfa762e1c3 MIPS: Refactor GIC clocksource code.
Reorganize some of the GIC clocksource driver code. Below is a list of
the various changes.

  * No longer select CSRC_GIC by default for Malta platform.
  * Limit choice for either the GIC or R4K clocksource, not both.
  * Change location in Makefile.
  * Created new 'gic_read_count' function in common 'irq-gic.c' file.
  * Change 'git_hpt_read' function in 'csrc-gic.c' to use new function.
  * Surround GIC specific code in Malta platform code with #ifdef's.
  * Only initialize the GIC clocksource if it was selected. Original
    code called it unconditionally if a GIC was found.

Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
2013-05-09 17:55:20 +02:00

40 lines
1 KiB
C

/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 2012 MIPS Technologies, Inc. All rights reserved.
*/
#include <linux/init.h>
#include <linux/time.h>
#include <asm/gic.h>
static cycle_t gic_hpt_read(struct clocksource *cs)
{
return gic_read_count();
}
static struct clocksource gic_clocksource = {
.name = "GIC",
.read = gic_hpt_read,
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};
void __init gic_clocksource_init(unsigned int frequency)
{
unsigned int config, bits;
/* Calculate the clocksource mask. */
GICREAD(GIC_REG(SHARED, GIC_SH_CONFIG), config);
bits = 32 + ((config & GIC_SH_CONFIG_COUNTBITS_MSK) >>
(GIC_SH_CONFIG_COUNTBITS_SHF - 2));
/* Set clocksource mask. */
gic_clocksource.mask = CLOCKSOURCE_MASK(bits);
/* Calculate a somewhat reasonable rating value. */
gic_clocksource.rating = 200 + frequency / 10000000;
clocksource_register_hz(&gic_clocksource, frequency);
}