linux-stable-rt/arch/powerpc/platforms/cell/pervasive.c

167 lines
3.9 KiB
C

/*
* CBE Pervasive Monitor and Debug
*
* (C) Copyright IBM Corporation 2005
*
* Authors: Maximino Aguilar (maguilar@us.ibm.com)
* Michael N. Day (mnday@us.ibm.com)
*
* 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, or (at your option)
* any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#undef DEBUG
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/percpu.h>
#include <linux/types.h>
#include <linux/kallsyms.h>
#include <asm/io.h>
#include <asm/machdep.h>
#include <asm/prom.h>
#include <asm/pgtable.h>
#include <asm/reg.h>
#include "pervasive.h"
#include "cbe_regs.h"
static DEFINE_SPINLOCK(cbe_pervasive_lock);
static void __init cbe_enable_pause_zero(void)
{
unsigned long thread_switch_control;
unsigned long temp_register;
struct cbe_pmd_regs __iomem *pregs;
spin_lock_irq(&cbe_pervasive_lock);
pregs = cbe_get_cpu_pmd_regs(smp_processor_id());
if (pregs == NULL)
goto out;
pr_debug("Power Management: CPU %d\n", smp_processor_id());
/* Enable Pause(0) control bit */
temp_register = in_be64(&pregs->pmcr);
out_be64(&pregs->pmcr,
temp_register | CBE_PMD_PAUSE_ZERO_CONTROL);
/* Enable DEC and EE interrupt request */
thread_switch_control = mfspr(SPRN_TSC_CELL);
thread_switch_control |= TSC_CELL_EE_ENABLE | TSC_CELL_EE_BOOST;
switch ((mfspr(SPRN_CTRLF) & CTRL_CT)) {
case CTRL_CT0:
thread_switch_control |= TSC_CELL_DEC_ENABLE_0;
break;
case CTRL_CT1:
thread_switch_control |= TSC_CELL_DEC_ENABLE_1;
break;
default:
printk(KERN_WARNING "%s: unknown configuration\n",
__FUNCTION__);
break;
}
mtspr(SPRN_TSC_CELL, thread_switch_control);
out:
spin_unlock_irq(&cbe_pervasive_lock);
}
static void cbe_idle(void)
{
unsigned long ctrl;
/* Why do we do that on every idle ? Couldn't that be done once for
* all or do we lose the state some way ? Also, the pmcr
* register setting, that can't be set once at boot ? We really want
* to move that away in order to implement a simple powersave
*/
cbe_enable_pause_zero();
while (1) {
if (!need_resched()) {
local_irq_disable();
while (!need_resched()) {
/* go into low thread priority */
HMT_low();
/*
* atomically disable thread execution
* and runlatch.
* External and Decrementer exceptions
* are still handled when the thread
* is disabled but now enter in
* cbe_system_reset_exception()
*/
ctrl = mfspr(SPRN_CTRLF);
ctrl &= ~(CTRL_RUNLATCH | CTRL_TE);
mtspr(SPRN_CTRLT, ctrl);
}
/* restore thread prio */
HMT_medium();
local_irq_enable();
}
/*
* turn runlatch on again before scheduling the
* process we just woke up
*/
ppc64_runlatch_on();
preempt_enable_no_resched();
schedule();
preempt_disable();
}
}
static int cbe_system_reset_exception(struct pt_regs *regs)
{
switch (regs->msr & SRR1_WAKEMASK) {
case SRR1_WAKEEE:
do_IRQ(regs);
break;
case SRR1_WAKEDEC:
timer_interrupt(regs);
break;
case SRR1_WAKEMT:
break;
#ifdef CONFIG_CBE_RAS
case SRR1_WAKESYSERR:
cbe_system_error_exception(regs);
break;
case SRR1_WAKETHERM:
cbe_thermal_exception(regs);
break;
#endif /* CONFIG_CBE_RAS */
default:
/* do system reset */
return 0;
}
/* everything handled */
return 1;
}
void __init cbe_pervasive_init(void)
{
if (!cpu_has_feature(CPU_FTR_PAUSE_ZERO))
return;
ppc_md.idle_loop = cbe_idle;
ppc_md.system_reset_exception = cbe_system_reset_exception;
}