mirror of
https://github.com/torvalds/linux.git
synced 2024-11-07 04:32:03 +00:00
2605f85275
This patch also removes setting cpu_present_mask as platforms should only re-initialize it in smp_prepare_cpus() if present != possible. Cc: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com> Signed-off-by: Michal Simek <michal.simek@xilinx.com>
132 lines
3.4 KiB
C
132 lines
3.4 KiB
C
/*
|
|
* This file contains Xilinx specific SMP code, used to start up
|
|
* the second processor.
|
|
*
|
|
* Copyright (C) 2011-2013 Xilinx
|
|
*
|
|
* based on linux/arch/arm/mach-realview/platsmp.c
|
|
*
|
|
* Copyright (C) 2002 ARM Ltd.
|
|
*
|
|
* This software is licensed under the terms of the GNU General Public
|
|
* License version 2, as published by the Free Software Foundation, and
|
|
* may be copied, distributed, and modified under those terms.
|
|
*
|
|
* 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/export.h>
|
|
#include <linux/jiffies.h>
|
|
#include <linux/init.h>
|
|
#include <linux/io.h>
|
|
#include <asm/cacheflush.h>
|
|
#include <asm/smp_scu.h>
|
|
#include <linux/irqchip/arm-gic.h>
|
|
#include "common.h"
|
|
|
|
/*
|
|
* Store number of cores in the system
|
|
* Because of scu_get_core_count() must be in __init section and can't
|
|
* be called from zynq_cpun_start() because it is not in __init section.
|
|
*/
|
|
static int ncores;
|
|
|
|
int zynq_cpun_start(u32 address, int cpu)
|
|
{
|
|
u32 trampoline_code_size = &zynq_secondary_trampoline_end -
|
|
&zynq_secondary_trampoline;
|
|
|
|
/* MS: Expectation that SLCR are directly map and accessible */
|
|
/* Not possible to jump to non aligned address */
|
|
if (!(address & 3) && (!address || (address >= trampoline_code_size))) {
|
|
/* Store pointer to ioremap area which points to address 0x0 */
|
|
static u8 __iomem *zero;
|
|
u32 trampoline_size = &zynq_secondary_trampoline_jump -
|
|
&zynq_secondary_trampoline;
|
|
|
|
zynq_slcr_cpu_stop(cpu);
|
|
if (address) {
|
|
if (__pa(PAGE_OFFSET)) {
|
|
zero = ioremap(0, trampoline_code_size);
|
|
if (!zero) {
|
|
pr_warn("BOOTUP jump vectors not accessible\n");
|
|
return -1;
|
|
}
|
|
} else {
|
|
zero = (__force u8 __iomem *)PAGE_OFFSET;
|
|
}
|
|
|
|
/*
|
|
* This is elegant way how to jump to any address
|
|
* 0x0: Load address at 0x8 to r0
|
|
* 0x4: Jump by mov instruction
|
|
* 0x8: Jumping address
|
|
*/
|
|
memcpy((__force void *)zero, &zynq_secondary_trampoline,
|
|
trampoline_size);
|
|
writel(address, zero + trampoline_size);
|
|
|
|
flush_cache_all();
|
|
outer_flush_range(0, trampoline_code_size);
|
|
smp_wmb();
|
|
|
|
if (__pa(PAGE_OFFSET))
|
|
iounmap(zero);
|
|
}
|
|
zynq_slcr_cpu_start(cpu);
|
|
|
|
return 0;
|
|
}
|
|
|
|
pr_warn("Can't start CPU%d: Wrong starting address %x\n", cpu, address);
|
|
|
|
return -1;
|
|
}
|
|
EXPORT_SYMBOL(zynq_cpun_start);
|
|
|
|
static int zynq_boot_secondary(unsigned int cpu,
|
|
struct task_struct *idle)
|
|
{
|
|
return zynq_cpun_start(virt_to_phys(zynq_secondary_startup), cpu);
|
|
}
|
|
|
|
/*
|
|
* Initialise the CPU possible map early - this describes the CPUs
|
|
* which may be present or become present in the system.
|
|
*/
|
|
static void __init zynq_smp_init_cpus(void)
|
|
{
|
|
int i;
|
|
|
|
ncores = scu_get_core_count(zynq_scu_base);
|
|
|
|
for (i = 0; i < ncores && i < CONFIG_NR_CPUS; i++)
|
|
set_cpu_possible(i, true);
|
|
}
|
|
|
|
static void __init zynq_smp_prepare_cpus(unsigned int max_cpus)
|
|
{
|
|
scu_enable(zynq_scu_base);
|
|
}
|
|
|
|
#ifdef CONFIG_HOTPLUG_CPU
|
|
static int zynq_cpu_kill(unsigned cpu)
|
|
{
|
|
zynq_slcr_cpu_stop(cpu);
|
|
return 1;
|
|
}
|
|
#endif
|
|
|
|
struct smp_operations zynq_smp_ops __initdata = {
|
|
.smp_init_cpus = zynq_smp_init_cpus,
|
|
.smp_prepare_cpus = zynq_smp_prepare_cpus,
|
|
.smp_boot_secondary = zynq_boot_secondary,
|
|
#ifdef CONFIG_HOTPLUG_CPU
|
|
.cpu_die = zynq_platform_cpu_die,
|
|
.cpu_kill = zynq_cpu_kill,
|
|
#endif
|
|
};
|