linux/arch/arm/mach-qcom/platsmp.c
Rohit Vaswani 188611af42 ARM: qcom: Re-organize platsmp to make it extensible
This makes it easy to add SMP support for new devices by keying
on a device node for the release sequence. We add the
enable-method property for the cpus property to specify that we
want to use the gcc-msm8660 release sequence (which is going to
look for the global clock controller device node to map some
Scorpion specific power and control registers). We also remove
the nr_cpus detection code as that is done generically in the DT
CPU detection code.

Signed-off-by: Rohit Vaswani <rvaswani@codeaurora.org>
[sboyd: Port to CPU_METHOD_OF_DECLARE]
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Kumar Gala <galak@codeaurora.org>
2014-02-11 15:00:37 -06:00

150 lines
3.4 KiB
C

/*
* Copyright (C) 2002 ARM Ltd.
* All Rights Reserved
* Copyright (c) 2010, Code Aurora Forum. All rights reserved.
* Copyright (c) 2014 The Linux Foundation. All rights reserved.
*
* 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.
*/
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/smp.h>
#include <linux/io.h>
#include <asm/smp_plat.h>
#include "scm-boot.h"
#define VDD_SC1_ARRAY_CLAMP_GFS_CTL 0x35a0
#define SCSS_CPU1CORE_RESET 0x2d80
#define SCSS_DBG_STATUS_CORE_PWRDUP 0x2e64
extern void secondary_startup(void);
static DEFINE_SPINLOCK(boot_lock);
#ifdef CONFIG_HOTPLUG_CPU
static void __ref qcom_cpu_die(unsigned int cpu)
{
wfi();
}
#endif
static void qcom_secondary_init(unsigned int cpu)
{
/*
* Synchronise with the boot thread.
*/
spin_lock(&boot_lock);
spin_unlock(&boot_lock);
}
static int scss_release_secondary(unsigned int cpu)
{
struct device_node *node;
void __iomem *base;
node = of_find_compatible_node(NULL, NULL, "qcom,gcc-msm8660");
if (!node) {
pr_err("%s: can't find node\n", __func__);
return -ENXIO;
}
base = of_iomap(node, 0);
of_node_put(node);
if (!base)
return -ENOMEM;
writel_relaxed(0, base + VDD_SC1_ARRAY_CLAMP_GFS_CTL);
writel_relaxed(0, base + SCSS_CPU1CORE_RESET);
writel_relaxed(3, base + SCSS_DBG_STATUS_CORE_PWRDUP);
mb();
iounmap(base);
return 0;
}
static DEFINE_PER_CPU(int, cold_boot_done);
static int qcom_boot_secondary(unsigned int cpu, int (*func)(unsigned int))
{
int ret = 0;
if (!per_cpu(cold_boot_done, cpu)) {
ret = func(cpu);
if (!ret)
per_cpu(cold_boot_done, cpu) = true;
}
/*
* set synchronisation state between this boot processor
* and the secondary one
*/
spin_lock(&boot_lock);
/*
* Send the secondary CPU a soft interrupt, thereby causing
* the boot monitor to read the system wide flags register,
* and branch to the address found there.
*/
arch_send_wakeup_ipi_mask(cpumask_of(cpu));
/*
* now the secondary core is starting up let it run its
* calibrations, then wait for it to finish
*/
spin_unlock(&boot_lock);
return ret;
}
static int msm8660_boot_secondary(unsigned int cpu, struct task_struct *idle)
{
return qcom_boot_secondary(cpu, scss_release_secondary);
}
static void __init qcom_smp_prepare_cpus(unsigned int max_cpus)
{
int cpu, map;
unsigned int flags = 0;
static const int cold_boot_flags[] = {
0,
SCM_FLAG_COLDBOOT_CPU1,
};
for_each_present_cpu(cpu) {
map = cpu_logical_map(cpu);
if (WARN_ON(map >= ARRAY_SIZE(cold_boot_flags))) {
set_cpu_present(cpu, false);
continue;
}
flags |= cold_boot_flags[map];
}
if (scm_set_boot_addr(virt_to_phys(secondary_startup), flags)) {
for_each_present_cpu(cpu) {
if (cpu == smp_processor_id())
continue;
set_cpu_present(cpu, false);
}
pr_warn("Failed to set CPU boot address, disabling SMP\n");
}
}
static struct smp_operations smp_msm8660_ops __initdata = {
.smp_prepare_cpus = qcom_smp_prepare_cpus,
.smp_secondary_init = qcom_secondary_init,
.smp_boot_secondary = msm8660_boot_secondary,
#ifdef CONFIG_HOTPLUG_CPU
.cpu_die = qcom_cpu_die,
#endif
};
CPU_METHOD_OF_DECLARE(qcom_smp, "qcom,gcc-msm8660", &smp_msm8660_ops);