7184659bed
Make smp_spin_table_cpu_postboot() static, because this function is used only in this file. Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
151 lines
3.7 KiB
C
151 lines
3.7 KiB
C
/*
|
|
* Spin Table SMP initialisation
|
|
*
|
|
* Copyright (C) 2013 ARM Ltd.
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*
|
|
* 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, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
#include <linux/delay.h>
|
|
#include <linux/init.h>
|
|
#include <linux/of.h>
|
|
#include <linux/smp.h>
|
|
|
|
#include <asm/cacheflush.h>
|
|
#include <asm/cpu_ops.h>
|
|
#include <asm/cputype.h>
|
|
#include <asm/smp_plat.h>
|
|
|
|
extern void secondary_holding_pen(void);
|
|
volatile unsigned long secondary_holding_pen_release = INVALID_HWID;
|
|
|
|
static phys_addr_t cpu_release_addr[NR_CPUS];
|
|
static DEFINE_RAW_SPINLOCK(boot_lock);
|
|
|
|
/*
|
|
* Write secondary_holding_pen_release in a way that is guaranteed to be
|
|
* visible to all observers, irrespective of whether they're taking part
|
|
* in coherency or not. This is necessary for the hotplug code to work
|
|
* reliably.
|
|
*/
|
|
static void write_pen_release(u64 val)
|
|
{
|
|
void *start = (void *)&secondary_holding_pen_release;
|
|
unsigned long size = sizeof(secondary_holding_pen_release);
|
|
|
|
secondary_holding_pen_release = val;
|
|
__flush_dcache_area(start, size);
|
|
}
|
|
|
|
|
|
static int smp_spin_table_cpu_init(struct device_node *dn, unsigned int cpu)
|
|
{
|
|
/*
|
|
* Determine the address from which the CPU is polling.
|
|
*/
|
|
if (of_property_read_u64(dn, "cpu-release-addr",
|
|
&cpu_release_addr[cpu])) {
|
|
pr_err("CPU %d: missing or invalid cpu-release-addr property\n",
|
|
cpu);
|
|
|
|
return -1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int smp_spin_table_cpu_prepare(unsigned int cpu)
|
|
{
|
|
void **release_addr;
|
|
|
|
if (!cpu_release_addr[cpu])
|
|
return -ENODEV;
|
|
|
|
release_addr = __va(cpu_release_addr[cpu]);
|
|
|
|
/*
|
|
* We write the release address as LE regardless of the native
|
|
* endianess of the kernel. Therefore, any boot-loaders that
|
|
* read this address need to convert this address to the
|
|
* boot-loader's endianess before jumping. This is mandated by
|
|
* the boot protocol.
|
|
*/
|
|
release_addr[0] = (void *) cpu_to_le64(__pa(secondary_holding_pen));
|
|
|
|
__flush_dcache_area(release_addr, sizeof(release_addr[0]));
|
|
|
|
/*
|
|
* Send an event to wake up the secondary CPU.
|
|
*/
|
|
sev();
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int smp_spin_table_cpu_boot(unsigned int cpu)
|
|
{
|
|
unsigned long timeout;
|
|
|
|
/*
|
|
* Set synchronisation state between this boot processor
|
|
* and the secondary one
|
|
*/
|
|
raw_spin_lock(&boot_lock);
|
|
|
|
/*
|
|
* Update the pen release flag.
|
|
*/
|
|
write_pen_release(cpu_logical_map(cpu));
|
|
|
|
/*
|
|
* Send an event, causing the secondaries to read pen_release.
|
|
*/
|
|
sev();
|
|
|
|
timeout = jiffies + (1 * HZ);
|
|
while (time_before(jiffies, timeout)) {
|
|
if (secondary_holding_pen_release == INVALID_HWID)
|
|
break;
|
|
udelay(10);
|
|
}
|
|
|
|
/*
|
|
* Now the secondary core is starting up let it run its
|
|
* calibrations, then wait for it to finish
|
|
*/
|
|
raw_spin_unlock(&boot_lock);
|
|
|
|
return secondary_holding_pen_release != INVALID_HWID ? -ENOSYS : 0;
|
|
}
|
|
|
|
static void smp_spin_table_cpu_postboot(void)
|
|
{
|
|
/*
|
|
* Let the primary processor know we're out of the pen.
|
|
*/
|
|
write_pen_release(INVALID_HWID);
|
|
|
|
/*
|
|
* Synchronise with the boot thread.
|
|
*/
|
|
raw_spin_lock(&boot_lock);
|
|
raw_spin_unlock(&boot_lock);
|
|
}
|
|
|
|
const struct cpu_operations smp_spin_table_ops = {
|
|
.name = "spin-table",
|
|
.cpu_init = smp_spin_table_cpu_init,
|
|
.cpu_prepare = smp_spin_table_cpu_prepare,
|
|
.cpu_boot = smp_spin_table_cpu_boot,
|
|
.cpu_postboot = smp_spin_table_cpu_postboot,
|
|
};
|