xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

ARM: Alpine: smp support

Browse Source 
This patch introduces support for waking up secondary CPU cores on
Alpine platform.

Signed-off-by: Barak Wasserstrom <barak@annapurnalabs.com>
Signed-off-by: Tsahee Zidenberg <tsahee@annapurnalabs.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
This commit is contained in:
Tsahee Zidenberg
2015-03-12 13:53:06 +02:00
committed by Arnd Bergmann
parent 3c215e64eb
commit e9e06f2853
6 changed files with 186 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

70
arch/arm/mach-alpine/alpine_cpu_pm.c Normal file
View File

@@ -0,0 +1,70 @@
/*
* Low-level power-management support for Alpine platform.
*
* Copyright (C) 2015 Annapurna Labs Ltd.
*
* 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.
*
* 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.
*/
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/regmap.h>
#include <linux/mfd/syscon.h>
#include "alpine_cpu_pm.h"
#include "alpine_cpu_resume.h"
/* NB registers */
#define AL_SYSFAB_POWER_CONTROL(cpu) (0x2000 + (cpu)*0x100 + 0x20)
static struct regmap *al_sysfabric;
static struct al_cpu_resume_regs __iomem *al_cpu_resume_regs;
static int wakeup_supported;
int alpine_cpu_wakeup(unsigned int phys_cpu, uint32_t phys_resume_addr)
{
if (!wakeup_supported)
return -ENOSYS;
/*
* Set CPU resume address -
* secure firmware running on boot will jump to this address
* after setting proper CPU mode, and initialiing e.g. secure
* regs (the same mode all CPUs are booted to - usually HYP)
*/
writel(phys_resume_addr,
&al_cpu_resume_regs->per_cpu[phys_cpu].resume_addr);
/* Power-up the CPU */
regmap_write(al_sysfabric, AL_SYSFAB_POWER_CONTROL(phys_cpu), 0);
return 0;
}
void __init alpine_cpu_pm_init(void)
{
struct device_node *np;
uint32_t watermark;
al_sysfabric = syscon_regmap_lookup_by_compatible("al,alpine-sysfabric-service");
np = of_find_compatible_node(NULL, NULL, "al,alpine-cpu-resume");
al_cpu_resume_regs = of_iomap(np, 0);
wakeup_supported = !IS_ERR(al_sysfabric) && al_cpu_resume_regs;
if (wakeup_supported) {
watermark = readl(&al_cpu_resume_regs->watermark);
wakeup_supported = (watermark & AL_CPU_RESUME_MAGIC_NUM_MASK)
== AL_CPU_RESUME_MAGIC_NUM;
}
}