openwrtv4/target/linux/oxnas/files/arch/arm/mach-oxnas/platsmp.c

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/*
* arch/arm/mach-ox820/platsmp.c
*
* Copyright (C) 2002 ARM Ltd.
* 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/device.h>
#include <linux/jiffies.h>
#include <linux/smp.h>
#include <linux/io.h>
#include <linux/dma-mapping.h>
#include <linux/cache.h>
#include <asm/cacheflush.h>
#include <asm/smp_scu.h>
#include <asm/tlbflush.h>
#include <asm/cputype.h>
#include <linux/delay.h>
#include <asm/fiq.h>
#include <linux/irqchip/arm-gic.h>
#include <mach/iomap.h>
#include <mach/smp.h>
#include <mach/hardware.h>
#include <mach/irqs.h>
#ifdef CONFIG_DMA_CACHE_FIQ_BROADCAST
#define FIQ_GENERATE 0x00000002
#define OXNAS_MAP_AREA 0x01000000
#define OXNAS_UNMAP_AREA 0x02000000
#define OXNAS_FLUSH_RANGE 0x03000000
struct fiq_req {
union {
struct {
const void *addr;
size_t size;
} map;
struct {
const void *addr;
size_t size;
} unmap;
struct {
const void *start;
const void *end;
} flush;
};
volatile uint flags;
void __iomem *reg;
} ____cacheline_aligned;
static struct fiq_handler fh = {
.name = "oxnas-fiq"
};
DEFINE_PER_CPU(struct fiq_req, fiq_data);
static inline void ox820_set_fiq_regs(unsigned int cpu)
{
struct pt_regs FIQ_regs;
struct fiq_req *fiq_req = &per_cpu(fiq_data, !cpu);
FIQ_regs.ARM_r8 = 0;
FIQ_regs.ARM_ip = (unsigned int)fiq_req;
FIQ_regs.ARM_sp = (int)(cpu ? RPSC_IRQ_SOFT : RPSA_IRQ_SOFT);
fiq_req->reg = cpu ? RPSC_IRQ_SOFT : RPSA_IRQ_SOFT;
set_fiq_regs(&FIQ_regs);
}
static void __init ox820_init_fiq(void)
{
void *fiqhandler_start;
unsigned int fiqhandler_length;
int ret;
fiqhandler_start = &ox820_fiq_start;
fiqhandler_length = &ox820_fiq_end - &ox820_fiq_start;
ret = claim_fiq(&fh);
if (ret)
return;
set_fiq_handler(fiqhandler_start, fiqhandler_length);
writel(IRQ_SOFT, RPSA_FIQ_IRQ_TO_FIQ);
writel(1, RPSA_FIQ_ENABLE);
writel(IRQ_SOFT, RPSC_FIQ_IRQ_TO_FIQ);
writel(1, RPSC_FIQ_ENABLE);
}
void fiq_dma_map_area(const void *addr, size_t size, int dir)
{
unsigned long flags;
struct fiq_req *req;
raw_local_irq_save(flags);
/* currently, not possible to take cpu0 down, so only check cpu1 */
if (!cpu_online(1)) {
raw_local_irq_restore(flags);
v6_dma_map_area(addr, size, dir);
return;
}
req = this_cpu_ptr(&fiq_data);
req->map.addr = addr;
req->map.size = size;
req->flags = dir | OXNAS_MAP_AREA;
smp_mb();
writel_relaxed(FIQ_GENERATE, req->reg);
v6_dma_map_area(addr, size, dir);
while (req->flags)
barrier();
raw_local_irq_restore(flags);
}
void fiq_dma_unmap_area(const void *addr, size_t size, int dir)
{
unsigned long flags;
struct fiq_req *req;
raw_local_irq_save(flags);
/* currently, not possible to take cpu0 down, so only check cpu1 */
if (!cpu_online(1)) {
raw_local_irq_restore(flags);
v6_dma_unmap_area(addr, size, dir);
return;
}
req = this_cpu_ptr(&fiq_data);
req->unmap.addr = addr;
req->unmap.size = size;
req->flags = dir | OXNAS_UNMAP_AREA;
smp_mb();
writel_relaxed(FIQ_GENERATE, req->reg);
v6_dma_unmap_area(addr, size, dir);
while (req->flags)
barrier();
raw_local_irq_restore(flags);
}
void fiq_dma_flush_range(const void *start, const void *end)
{
unsigned long flags;
struct fiq_req *req;
raw_local_irq_save(flags);
/* currently, not possible to take cpu0 down, so only check cpu1 */
if (!cpu_online(1)) {
raw_local_irq_restore(flags);
v6_dma_flush_range(start, end);
return;
}
req = this_cpu_ptr(&fiq_data);
req->flush.start = start;
req->flush.end = end;
req->flags = OXNAS_FLUSH_RANGE;
smp_mb();
writel_relaxed(FIQ_GENERATE, req->reg);
v6_dma_flush_range(start, end);
while (req->flags)
barrier();
raw_local_irq_restore(flags);
}
void fiq_flush_kern_dcache_area(void *addr, size_t size)
{
fiq_dma_flush_range(addr, addr + size);
}
#else
#define ox820_set_fiq_regs(cpu) do {} while (0) /* nothing */
#define ox820_init_fiq() do {} while (0) /* nothing */
#endif /* DMA_CACHE_FIQ_BROADCAST */
static DEFINE_SPINLOCK(boot_lock);
void ox820_secondary_init(unsigned int cpu)
{
/*
* Setup Secondary Core FIQ regs
*/
ox820_set_fiq_regs(1);
/*
* let the primary processor know we're out of the
* pen, then head off into the C entry point
*/
write_pen_release(-1);
/*
* Synchronise with the boot thread.
*/
spin_lock(&boot_lock);
spin_unlock(&boot_lock);
}
int ox820_boot_secondary(unsigned int cpu, struct task_struct *idle)
{
unsigned long timeout;
/*
* Set synchronisation state between this boot processor
* and the secondary one
*/
spin_lock(&boot_lock);
/*
* This is really belt and braces; we hold unintended secondary
* CPUs in the holding pen until we're ready for them. However,
* since we haven't sent them a soft interrupt, they shouldn't
* be there.
*/
write_pen_release(cpu);
writel(1, IOMEM(OXNAS_GICN_BASE_VA(cpu) + GIC_CPU_CTRL));
/*
* 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));
timeout = jiffies + (1 * HZ);
while (time_before(jiffies, timeout)) {
smp_rmb();
if (read_pen_release() == -1)
break;
udelay(10);
}
/*
* now the secondary core is starting up let it run its
* calibrations, then wait for it to finish
*/
spin_unlock(&boot_lock);
return read_pen_release() != -1 ? -ENOSYS : 0;
}
void *scu_base_addr(void)
{
return IOMEM(OXNAS_SCU_BASE_VA);
}
/*
* Initialise the CPU possible map early - this describes the CPUs
* which may be present or become present in the system.
*/
static void __init ox820_smp_init_cpus(void)
{
void __iomem *scu_base = scu_base_addr();
unsigned int i, ncores;
ncores = scu_base ? scu_get_core_count(scu_base) : 1;
/* sanity check */
if (ncores > nr_cpu_ids) {
pr_warn("SMP: %u cores greater than maximum (%u), clipping\n",
ncores, nr_cpu_ids);
ncores = nr_cpu_ids;
}
for (i = 0; i < ncores; i++)
set_cpu_possible(i, true);
}
static void __init ox820_smp_prepare_cpus(unsigned int max_cpus)
{
scu_enable(scu_base_addr());
/*
* Write the address of secondary startup into the
* system-wide flags register. The BootMonitor waits
* until it receives a soft interrupt, and then the
* secondary CPU branches to this address.
*/
writel(virt_to_phys(ox820_secondary_startup),
HOLDINGPEN_LOCATION);
ox820_init_fiq();
ox820_set_fiq_regs(0);
}
struct smp_operations ox820_smp_ops __initdata = {
.smp_init_cpus = ox820_smp_init_cpus,
.smp_prepare_cpus = ox820_smp_prepare_cpus,
.smp_secondary_init = ox820_secondary_init,
.smp_boot_secondary = ox820_boot_secondary,
#ifdef CONFIG_HOTPLUG_CPU
.cpu_die = ox820_cpu_die,
#endif
};