linux/drivers/cpufreq/ppc_cbe_cpufreq_pervasive.c
Thomas Gleixner de6cc6515a treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 153
Based on 1 normalized pattern(s):

  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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 77 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Armijn Hemel <armijn@tjaldur.nl>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.837555891@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00

103 lines
2.2 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* pervasive backend for the cbe_cpufreq driver
*
* This driver makes use of the pervasive unit to
* engage the desired frequency.
*
* (C) Copyright IBM Deutschland Entwicklung GmbH 2005-2007
*
* Author: Christian Krafft <krafft@de.ibm.com>
*/
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/time.h>
#include <asm/machdep.h>
#include <asm/hw_irq.h>
#include <asm/cell-regs.h>
#include "ppc_cbe_cpufreq.h"
/* to write to MIC register */
static u64 MIC_Slow_Fast_Timer_table[] = {
[0 ... 7] = 0x007fc00000000000ull,
};
/* more values for the MIC */
static u64 MIC_Slow_Next_Timer_table[] = {
0x0000240000000000ull,
0x0000268000000000ull,
0x000029C000000000ull,
0x00002D0000000000ull,
0x0000300000000000ull,
0x0000334000000000ull,
0x000039C000000000ull,
0x00003FC000000000ull,
};
int cbe_cpufreq_set_pmode(int cpu, unsigned int pmode)
{
struct cbe_pmd_regs __iomem *pmd_regs;
struct cbe_mic_tm_regs __iomem *mic_tm_regs;
unsigned long flags;
u64 value;
#ifdef DEBUG
long time;
#endif
local_irq_save(flags);
mic_tm_regs = cbe_get_cpu_mic_tm_regs(cpu);
pmd_regs = cbe_get_cpu_pmd_regs(cpu);
#ifdef DEBUG
time = jiffies;
#endif
out_be64(&mic_tm_regs->slow_fast_timer_0, MIC_Slow_Fast_Timer_table[pmode]);
out_be64(&mic_tm_regs->slow_fast_timer_1, MIC_Slow_Fast_Timer_table[pmode]);
out_be64(&mic_tm_regs->slow_next_timer_0, MIC_Slow_Next_Timer_table[pmode]);
out_be64(&mic_tm_regs->slow_next_timer_1, MIC_Slow_Next_Timer_table[pmode]);
value = in_be64(&pmd_regs->pmcr);
/* set bits to zero */
value &= 0xFFFFFFFFFFFFFFF8ull;
/* set bits to next pmode */
value |= pmode;
out_be64(&pmd_regs->pmcr, value);
#ifdef DEBUG
/* wait until new pmode appears in status register */
value = in_be64(&pmd_regs->pmsr) & 0x07;
while (value != pmode) {
cpu_relax();
value = in_be64(&pmd_regs->pmsr) & 0x07;
}
time = jiffies - time;
time = jiffies_to_msecs(time);
pr_debug("had to wait %lu ms for a transition using " \
"pervasive unit\n", time);
#endif
local_irq_restore(flags);
return 0;
}
int cbe_cpufreq_get_pmode(int cpu)
{
int ret;
struct cbe_pmd_regs __iomem *pmd_regs;
pmd_regs = cbe_get_cpu_pmd_regs(cpu);
ret = in_be64(&pmd_regs->pmsr) & 0x07;
return ret;
}