mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-12-10 20:44:09 +08:00
d2685fb7b4
Signed-off-by: Philippe Gerum <rpm@xenomai.org> Signed-off-by: Li Yi <yi.li@analog.com> Signed-off-by: Mike Frysinger <vapier@gentoo.org>
405 lines
10 KiB
C
405 lines
10 KiB
C
/* -*- linux-c -*-
|
|
* linux/arch/blackfin/kernel/ipipe.c
|
|
*
|
|
* Copyright (C) 2005-2007 Philippe Gerum.
|
|
*
|
|
* 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, Inc., 675 Mass Ave, Cambridge MA 02139,
|
|
* USA; 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.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write to the Free Software
|
|
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
|
|
*
|
|
* Architecture-dependent I-pipe support for the Blackfin.
|
|
*/
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/module.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/percpu.h>
|
|
#include <linux/bitops.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/errno.h>
|
|
#include <linux/kthread.h>
|
|
#include <linux/unistd.h>
|
|
#include <linux/io.h>
|
|
#include <asm/system.h>
|
|
#include <asm/atomic.h>
|
|
|
|
DEFINE_PER_CPU(struct pt_regs, __ipipe_tick_regs);
|
|
|
|
asmlinkage void asm_do_IRQ(unsigned int irq, struct pt_regs *regs);
|
|
|
|
static void __ipipe_no_irqtail(void);
|
|
|
|
unsigned long __ipipe_irq_tail_hook = (unsigned long)&__ipipe_no_irqtail;
|
|
EXPORT_SYMBOL(__ipipe_irq_tail_hook);
|
|
|
|
unsigned long __ipipe_core_clock;
|
|
EXPORT_SYMBOL(__ipipe_core_clock);
|
|
|
|
unsigned long __ipipe_freq_scale;
|
|
EXPORT_SYMBOL(__ipipe_freq_scale);
|
|
|
|
atomic_t __ipipe_irq_lvdepth[IVG15 + 1];
|
|
|
|
unsigned long __ipipe_irq_lvmask = bfin_no_irqs;
|
|
EXPORT_SYMBOL(__ipipe_irq_lvmask);
|
|
|
|
static void __ipipe_ack_irq(unsigned irq, struct irq_desc *desc)
|
|
{
|
|
desc->ipipe_ack(irq, desc);
|
|
}
|
|
|
|
/*
|
|
* __ipipe_enable_pipeline() -- We are running on the boot CPU, hw
|
|
* interrupts are off, and secondary CPUs are still lost in space.
|
|
*/
|
|
void __ipipe_enable_pipeline(void)
|
|
{
|
|
unsigned irq;
|
|
|
|
__ipipe_core_clock = get_cclk(); /* Fetch this once. */
|
|
__ipipe_freq_scale = 1000000000UL / __ipipe_core_clock;
|
|
|
|
for (irq = 0; irq < NR_IRQS; ++irq)
|
|
ipipe_virtualize_irq(ipipe_root_domain,
|
|
irq,
|
|
(ipipe_irq_handler_t)&asm_do_IRQ,
|
|
NULL,
|
|
&__ipipe_ack_irq,
|
|
IPIPE_HANDLE_MASK | IPIPE_PASS_MASK);
|
|
}
|
|
|
|
/*
|
|
* __ipipe_handle_irq() -- IPIPE's generic IRQ handler. An optimistic
|
|
* interrupt protection log is maintained here for each domain. Hw
|
|
* interrupts are masked on entry.
|
|
*/
|
|
void __ipipe_handle_irq(unsigned irq, struct pt_regs *regs)
|
|
{
|
|
struct ipipe_percpu_domain_data *p = ipipe_root_cpudom_ptr();
|
|
struct ipipe_domain *this_domain, *next_domain;
|
|
struct list_head *head, *pos;
|
|
struct ipipe_irqdesc *idesc;
|
|
int m_ack, s = -1;
|
|
|
|
/*
|
|
* Software-triggered IRQs do not need any ack. The contents
|
|
* of the register frame should only be used when processing
|
|
* the timer interrupt, but not for handling any other
|
|
* interrupt.
|
|
*/
|
|
m_ack = (regs == NULL || irq == IRQ_SYSTMR || irq == IRQ_CORETMR);
|
|
this_domain = __ipipe_current_domain;
|
|
idesc = &this_domain->irqs[irq];
|
|
|
|
if (unlikely(test_bit(IPIPE_STICKY_FLAG, &idesc->control)))
|
|
head = &this_domain->p_link;
|
|
else {
|
|
head = __ipipe_pipeline.next;
|
|
next_domain = list_entry(head, struct ipipe_domain, p_link);
|
|
idesc = &next_domain->irqs[irq];
|
|
if (likely(test_bit(IPIPE_WIRED_FLAG, &idesc->control))) {
|
|
if (!m_ack && idesc->acknowledge != NULL)
|
|
idesc->acknowledge(irq, irq_to_desc(irq));
|
|
if (test_bit(IPIPE_SYNCDEFER_FLAG, &p->status))
|
|
s = __test_and_set_bit(IPIPE_STALL_FLAG,
|
|
&p->status);
|
|
__ipipe_dispatch_wired(next_domain, irq);
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
/* Ack the interrupt. */
|
|
|
|
pos = head;
|
|
while (pos != &__ipipe_pipeline) {
|
|
next_domain = list_entry(pos, struct ipipe_domain, p_link);
|
|
idesc = &next_domain->irqs[irq];
|
|
if (test_bit(IPIPE_HANDLE_FLAG, &idesc->control)) {
|
|
__ipipe_set_irq_pending(next_domain, irq);
|
|
if (!m_ack && idesc->acknowledge != NULL) {
|
|
idesc->acknowledge(irq, irq_to_desc(irq));
|
|
m_ack = 1;
|
|
}
|
|
}
|
|
if (!test_bit(IPIPE_PASS_FLAG, &idesc->control))
|
|
break;
|
|
pos = next_domain->p_link.next;
|
|
}
|
|
|
|
/*
|
|
* Now walk the pipeline, yielding control to the highest
|
|
* priority domain that has pending interrupt(s) or
|
|
* immediately to the current domain if the interrupt has been
|
|
* marked as 'sticky'. This search does not go beyond the
|
|
* current domain in the pipeline. We also enforce the
|
|
* additional root stage lock (blackfin-specific).
|
|
*/
|
|
if (test_bit(IPIPE_SYNCDEFER_FLAG, &p->status))
|
|
s = __test_and_set_bit(IPIPE_STALL_FLAG, &p->status);
|
|
|
|
/*
|
|
* If the interrupt preempted the head domain, then do not
|
|
* even try to walk the pipeline, unless an interrupt is
|
|
* pending for it.
|
|
*/
|
|
if (test_bit(IPIPE_AHEAD_FLAG, &this_domain->flags) &&
|
|
ipipe_head_cpudom_var(irqpend_himask) == 0)
|
|
goto out;
|
|
|
|
__ipipe_walk_pipeline(head);
|
|
out:
|
|
if (!s)
|
|
__clear_bit(IPIPE_STALL_FLAG, &p->status);
|
|
}
|
|
|
|
void __ipipe_enable_irqdesc(struct ipipe_domain *ipd, unsigned irq)
|
|
{
|
|
struct irq_desc *desc = irq_to_desc(irq);
|
|
int prio = __ipipe_get_irq_priority(irq);
|
|
|
|
desc->depth = 0;
|
|
if (ipd != &ipipe_root &&
|
|
atomic_inc_return(&__ipipe_irq_lvdepth[prio]) == 1)
|
|
__set_bit(prio, &__ipipe_irq_lvmask);
|
|
}
|
|
EXPORT_SYMBOL(__ipipe_enable_irqdesc);
|
|
|
|
void __ipipe_disable_irqdesc(struct ipipe_domain *ipd, unsigned irq)
|
|
{
|
|
int prio = __ipipe_get_irq_priority(irq);
|
|
|
|
if (ipd != &ipipe_root &&
|
|
atomic_dec_and_test(&__ipipe_irq_lvdepth[prio]))
|
|
__clear_bit(prio, &__ipipe_irq_lvmask);
|
|
}
|
|
EXPORT_SYMBOL(__ipipe_disable_irqdesc);
|
|
|
|
int __ipipe_syscall_root(struct pt_regs *regs)
|
|
{
|
|
struct ipipe_percpu_domain_data *p;
|
|
unsigned long flags;
|
|
int ret;
|
|
|
|
/*
|
|
* We need to run the IRQ tail hook whenever we don't
|
|
* propagate a syscall to higher domains, because we know that
|
|
* important operations might be pending there (e.g. Xenomai
|
|
* deferred rescheduling).
|
|
*/
|
|
|
|
if (regs->orig_p0 < NR_syscalls) {
|
|
void (*hook)(void) = (void (*)(void))__ipipe_irq_tail_hook;
|
|
hook();
|
|
if ((current->flags & PF_EVNOTIFY) == 0)
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* This routine either returns:
|
|
* 0 -- if the syscall is to be passed to Linux;
|
|
* >0 -- if the syscall should not be passed to Linux, and no
|
|
* tail work should be performed;
|
|
* <0 -- if the syscall should not be passed to Linux but the
|
|
* tail work has to be performed (for handling signals etc).
|
|
*/
|
|
|
|
if (!__ipipe_event_monitored_p(IPIPE_EVENT_SYSCALL))
|
|
return 0;
|
|
|
|
ret = __ipipe_dispatch_event(IPIPE_EVENT_SYSCALL, regs);
|
|
|
|
local_irq_save_hw(flags);
|
|
|
|
if (!__ipipe_root_domain_p) {
|
|
local_irq_restore_hw(flags);
|
|
return 1;
|
|
}
|
|
|
|
p = ipipe_root_cpudom_ptr();
|
|
if ((p->irqpend_himask & IPIPE_IRQMASK_VIRT) != 0)
|
|
__ipipe_sync_pipeline(IPIPE_IRQMASK_VIRT);
|
|
|
|
local_irq_restore_hw(flags);
|
|
|
|
return -ret;
|
|
}
|
|
|
|
unsigned long ipipe_critical_enter(void (*syncfn) (void))
|
|
{
|
|
unsigned long flags;
|
|
|
|
local_irq_save_hw(flags);
|
|
|
|
return flags;
|
|
}
|
|
|
|
void ipipe_critical_exit(unsigned long flags)
|
|
{
|
|
local_irq_restore_hw(flags);
|
|
}
|
|
|
|
static void __ipipe_no_irqtail(void)
|
|
{
|
|
}
|
|
|
|
int ipipe_get_sysinfo(struct ipipe_sysinfo *info)
|
|
{
|
|
info->ncpus = num_online_cpus();
|
|
info->cpufreq = ipipe_cpu_freq();
|
|
info->archdep.tmirq = IPIPE_TIMER_IRQ;
|
|
info->archdep.tmfreq = info->cpufreq;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* ipipe_trigger_irq() -- Push the interrupt at front of the pipeline
|
|
* just like if it has been actually received from a hw source. Also
|
|
* works for virtual interrupts.
|
|
*/
|
|
int ipipe_trigger_irq(unsigned irq)
|
|
{
|
|
unsigned long flags;
|
|
|
|
#ifdef CONFIG_IPIPE_DEBUG
|
|
if (irq >= IPIPE_NR_IRQS ||
|
|
(ipipe_virtual_irq_p(irq)
|
|
&& !test_bit(irq - IPIPE_VIRQ_BASE, &__ipipe_virtual_irq_map)))
|
|
return -EINVAL;
|
|
#endif
|
|
|
|
local_irq_save_hw(flags);
|
|
__ipipe_handle_irq(irq, NULL);
|
|
local_irq_restore_hw(flags);
|
|
|
|
return 1;
|
|
}
|
|
|
|
asmlinkage void __ipipe_sync_root(void)
|
|
{
|
|
void (*irq_tail_hook)(void) = (void (*)(void))__ipipe_irq_tail_hook;
|
|
unsigned long flags;
|
|
|
|
BUG_ON(irqs_disabled());
|
|
|
|
local_irq_save_hw(flags);
|
|
|
|
if (irq_tail_hook)
|
|
irq_tail_hook();
|
|
|
|
clear_thread_flag(TIF_IRQ_SYNC);
|
|
|
|
if (ipipe_root_cpudom_var(irqpend_himask) != 0)
|
|
__ipipe_sync_pipeline(IPIPE_IRQMASK_ANY);
|
|
|
|
local_irq_restore_hw(flags);
|
|
}
|
|
|
|
void ___ipipe_sync_pipeline(unsigned long syncmask)
|
|
{
|
|
if (__ipipe_root_domain_p &&
|
|
test_bit(IPIPE_SYNCDEFER_FLAG, &ipipe_root_cpudom_var(status)))
|
|
return;
|
|
|
|
__ipipe_sync_stage(syncmask);
|
|
}
|
|
|
|
void __ipipe_disable_root_irqs_hw(void)
|
|
{
|
|
/*
|
|
* This code is called by the ins{bwl} routines (see
|
|
* arch/blackfin/lib/ins.S), which are heavily used by the
|
|
* network stack. It masks all interrupts but those handled by
|
|
* non-root domains, so that we keep decent network transfer
|
|
* rates for Linux without inducing pathological jitter for
|
|
* the real-time domain.
|
|
*/
|
|
bfin_sti(__ipipe_irq_lvmask);
|
|
__set_bit(IPIPE_STALL_FLAG, &ipipe_root_cpudom_var(status));
|
|
}
|
|
|
|
void __ipipe_enable_root_irqs_hw(void)
|
|
{
|
|
__clear_bit(IPIPE_STALL_FLAG, &ipipe_root_cpudom_var(status));
|
|
bfin_sti(bfin_irq_flags);
|
|
}
|
|
|
|
/*
|
|
* We could use standard atomic bitops in the following root status
|
|
* manipulation routines, but let's prepare for SMP support in the
|
|
* same move, preventing CPU migration as required.
|
|
*/
|
|
void __ipipe_stall_root(void)
|
|
{
|
|
unsigned long *p, flags;
|
|
|
|
local_irq_save_hw(flags);
|
|
p = &__ipipe_root_status;
|
|
__set_bit(IPIPE_STALL_FLAG, p);
|
|
local_irq_restore_hw(flags);
|
|
}
|
|
EXPORT_SYMBOL(__ipipe_stall_root);
|
|
|
|
unsigned long __ipipe_test_and_stall_root(void)
|
|
{
|
|
unsigned long *p, flags;
|
|
int x;
|
|
|
|
local_irq_save_hw(flags);
|
|
p = &__ipipe_root_status;
|
|
x = __test_and_set_bit(IPIPE_STALL_FLAG, p);
|
|
local_irq_restore_hw(flags);
|
|
|
|
return x;
|
|
}
|
|
EXPORT_SYMBOL(__ipipe_test_and_stall_root);
|
|
|
|
unsigned long __ipipe_test_root(void)
|
|
{
|
|
const unsigned long *p;
|
|
unsigned long flags;
|
|
int x;
|
|
|
|
local_irq_save_hw_smp(flags);
|
|
p = &__ipipe_root_status;
|
|
x = test_bit(IPIPE_STALL_FLAG, p);
|
|
local_irq_restore_hw_smp(flags);
|
|
|
|
return x;
|
|
}
|
|
EXPORT_SYMBOL(__ipipe_test_root);
|
|
|
|
void __ipipe_lock_root(void)
|
|
{
|
|
unsigned long *p, flags;
|
|
|
|
local_irq_save_hw(flags);
|
|
p = &__ipipe_root_status;
|
|
__set_bit(IPIPE_SYNCDEFER_FLAG, p);
|
|
local_irq_restore_hw(flags);
|
|
}
|
|
EXPORT_SYMBOL(__ipipe_lock_root);
|
|
|
|
void __ipipe_unlock_root(void)
|
|
{
|
|
unsigned long *p, flags;
|
|
|
|
local_irq_save_hw(flags);
|
|
p = &__ipipe_root_status;
|
|
__clear_bit(IPIPE_SYNCDEFER_FLAG, p);
|
|
local_irq_restore_hw(flags);
|
|
}
|
|
EXPORT_SYMBOL(__ipipe_unlock_root);
|