kernel_optimize_test/arch/mips/kernel/smp-cmp.c
Ralf Baechle b633648c5a MIPS: MT: Remove SMTC support
Nobody is maintaining SMTC anymore and there also seems to be no userbase.
Which is a pity - the SMTC technology primarily developed by Kevin D.
Kissell <kevink@paralogos.com> is an ingenious demonstration for the MT
ASE's power and elegance.

Based on Markos Chandras <Markos.Chandras@imgtec.com> patch
https://patchwork.linux-mips.org/patch/6719/ which while very similar did
no longer apply cleanly when I tried to merge it plus some additional
post-SMTC cleanup - SMTC was a feature as tricky to remove as it was to
merge once upon a time.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-05-24 00:07:01 +02:00

166 lines
4.2 KiB
C

/*
* This program is free software; you can distribute 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 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.
*
* Copyright (C) 2007 MIPS Technologies, Inc.
* Chris Dearman (chris@mips.com)
*/
#undef DEBUG
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/smp.h>
#include <linux/cpumask.h>
#include <linux/interrupt.h>
#include <linux/compiler.h>
#include <linux/atomic.h>
#include <asm/cacheflush.h>
#include <asm/cpu.h>
#include <asm/processor.h>
#include <asm/hardirq.h>
#include <asm/mmu_context.h>
#include <asm/smp.h>
#include <asm/time.h>
#include <asm/mipsregs.h>
#include <asm/mipsmtregs.h>
#include <asm/mips_mt.h>
#include <asm/amon.h>
#include <asm/gic.h>
static void cmp_init_secondary(void)
{
struct cpuinfo_mips *c __maybe_unused = &current_cpu_data;
/* Assume GIC is present */
change_c0_status(ST0_IM, STATUSF_IP3 | STATUSF_IP4 | STATUSF_IP6 |
STATUSF_IP7);
/* Enable per-cpu interrupts: platform specific */
#ifdef CONFIG_MIPS_MT_SMP
if (cpu_has_mipsmt)
c->vpe_id = (read_c0_tcbind() >> TCBIND_CURVPE_SHIFT) &
TCBIND_CURVPE;
#endif
}
static void cmp_smp_finish(void)
{
pr_debug("SMPCMP: CPU%d: %s\n", smp_processor_id(), __func__);
/* CDFIXME: remove this? */
write_c0_compare(read_c0_count() + (8 * mips_hpt_frequency / HZ));
#ifdef CONFIG_MIPS_MT_FPAFF
/* If we have an FPU, enroll ourselves in the FPU-full mask */
if (cpu_has_fpu)
cpu_set(smp_processor_id(), mt_fpu_cpumask);
#endif /* CONFIG_MIPS_MT_FPAFF */
local_irq_enable();
}
static void cmp_cpus_done(void)
{
pr_debug("SMPCMP: CPU%d: %s\n", smp_processor_id(), __func__);
}
/*
* Setup the PC, SP, and GP of a secondary processor and start it running
* smp_bootstrap is the place to resume from
* __KSTK_TOS(idle) is apparently the stack pointer
* (unsigned long)idle->thread_info the gp
*/
static void cmp_boot_secondary(int cpu, struct task_struct *idle)
{
struct thread_info *gp = task_thread_info(idle);
unsigned long sp = __KSTK_TOS(idle);
unsigned long pc = (unsigned long)&smp_bootstrap;
unsigned long a0 = 0;
pr_debug("SMPCMP: CPU%d: %s cpu %d\n", smp_processor_id(),
__func__, cpu);
#if 0
/* Needed? */
flush_icache_range((unsigned long)gp,
(unsigned long)(gp + sizeof(struct thread_info)));
#endif
amon_cpu_start(cpu, pc, sp, (unsigned long)gp, a0);
}
/*
* Common setup before any secondaries are started
*/
void __init cmp_smp_setup(void)
{
int i;
int ncpu = 0;
pr_debug("SMPCMP: CPU%d: %s\n", smp_processor_id(), __func__);
#ifdef CONFIG_MIPS_MT_FPAFF
/* If we have an FPU, enroll ourselves in the FPU-full mask */
if (cpu_has_fpu)
cpu_set(0, mt_fpu_cpumask);
#endif /* CONFIG_MIPS_MT_FPAFF */
for (i = 1; i < NR_CPUS; i++) {
if (amon_cpu_avail(i)) {
set_cpu_possible(i, true);
__cpu_number_map[i] = ++ncpu;
__cpu_logical_map[ncpu] = i;
}
}
if (cpu_has_mipsmt) {
unsigned int nvpe = 1;
#ifdef CONFIG_MIPS_MT_SMP
unsigned int mvpconf0 = read_c0_mvpconf0();
nvpe = ((mvpconf0 & MVPCONF0_PVPE) >> MVPCONF0_PVPE_SHIFT) + 1;
#endif
smp_num_siblings = nvpe;
}
pr_info("Detected %i available secondary CPU(s)\n", ncpu);
}
void __init cmp_prepare_cpus(unsigned int max_cpus)
{
pr_debug("SMPCMP: CPU%d: %s max_cpus=%d\n",
smp_processor_id(), __func__, max_cpus);
#ifdef CONFIG_MIPS_MT
/*
* FIXME: some of these options are per-system, some per-core and
* some per-cpu
*/
mips_mt_set_cpuoptions();
#endif
}
struct plat_smp_ops cmp_smp_ops = {
.send_ipi_single = gic_send_ipi_single,
.send_ipi_mask = gic_send_ipi_mask,
.init_secondary = cmp_init_secondary,
.smp_finish = cmp_smp_finish,
.cpus_done = cmp_cpus_done,
.boot_secondary = cmp_boot_secondary,
.smp_setup = cmp_smp_setup,
.prepare_cpus = cmp_prepare_cpus,
};