MIPS: Loongson 3: Add Loongson-3 SMP support

IPI registers of Loongson-3 include IPI_SET, IPI_CLEAR, IPI_STATUS,
IPI_EN and IPI_MAILBOX_BUF. Each bit of IPI_STATUS indicate a type of
IPI and IPI_EN indicate whether the IPI is enabled. The sender write 1
to IPI_SET bits generate IPIs in IPI_STATUS, and receiver write 1 to
bits of IPI_CLEAR to clear IPIs. IPI_MAILBOX_BUF are used to deliver
more information about IPIs.

Why we change code in arch/mips/loongson/common/setup.c?

If without this change, when SMP configured, system cannot boot since
it hang at printk() in cgroup_init_early(). The root cause is:

console_trylock()
  \-->down_trylock(&console_sem)
    \-->raw_spin_unlock_irqrestore(&sem->lock, flags)
      \-->_raw_spin_unlock_irqrestore()(SMP/UP have different versions)
        \-->__raw_spin_unlock_irqrestore()  (following is the SMP case)
          \-->do_raw_spin_unlock()
            \-->arch_spin_unlock()
              \-->nudge_writes()
                \-->mb()
                  \-->wbflush()
                    \-->__wbflush()

In previous code __wbflush() is initialized in plat_mem_setup(), but
cgroup_init_early() is called before plat_mem_setup(). Therefore, In
this patch we make changes to avoid boot failure.

Signed-off-by: Huacai Chen <chenhc@lemote.com>
Signed-off-by: Hongliang Tao <taohl@lemote.com>
Signed-off-by: Hua Yan <yanh@lemote.com>
Tested-by: Alex Smith <alex.smith@imgtec.com>
Reviewed-by: Alex Smith <alex.smith@imgtec.com>
Cc: John Crispin <john@phrozen.org>
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: Aurelien Jarno <aurelien@aurel32.net>
Cc: linux-mips@linux-mips.org
Cc: Fuxin Zhang <zhangfx@lemote.com>
Cc: Zhangjin Wu <wuzhangjin@gmail.com>
Patchwork: https://patchwork.linux-mips.org/patch/6638
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This commit is contained in:
Huacai Chen 2014-03-21 18:44:08 +08:00 committed by Ralf Baechle
parent 0e476d9124
commit 300459d558
8 changed files with 326 additions and 5 deletions

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@ -37,5 +37,7 @@
#endif
extern void loongson3_ipi_interrupt(struct pt_regs *regs);
#include_next <irq.h>
#endif /* __ASM_MACH_LOONGSON_IRQ_H_ */

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@ -27,6 +27,7 @@ extern void mach_prepare_shutdown(void);
/* environment arguments from bootloader */
extern u32 cpu_clock_freq;
extern u32 memsize, highmemsize;
extern struct plat_smp_ops loongson3_smp_ops;
/* loongson-specific command line, env and memory initialization */
extern void __init prom_init_memory(void);

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@ -9,6 +9,7 @@
*/
#include <linux/bootmem.h>
#include <asm/smp-ops.h>
#include <loongson.h>
@ -33,6 +34,7 @@ void __init prom_init(void)
/*init the uart base address */
prom_init_uart_base();
register_smp_ops(&loongson3_smp_ops);
}
void __init prom_free_prom_memory(void)

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@ -18,9 +18,6 @@
#include <linux/screen_info.h>
#endif
void (*__wbflush)(void);
EXPORT_SYMBOL(__wbflush);
static void wbflush_loongson(void)
{
asm(".set\tpush\n\t"
@ -32,10 +29,11 @@ static void wbflush_loongson(void)
".set mips0\n\t");
}
void (*__wbflush)(void) = wbflush_loongson;
EXPORT_SYMBOL(__wbflush);
void __init plat_mem_setup(void)
{
__wbflush = wbflush_loongson;
#ifdef CONFIG_VT
#if defined(CONFIG_VGA_CONSOLE)
conswitchp = &vga_con;

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@ -2,3 +2,5 @@
# Makefile for Loongson-3 family machines
#
obj-y += irq.o
obj-$(CONFIG_SMP) += smp.o

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@ -26,6 +26,10 @@ void mach_irq_dispatch(unsigned int pending)
{
if (pending & CAUSEF_IP7)
do_IRQ(LOONGSON_TIMER_IRQ);
#if defined(CONFIG_SMP)
else if (pending & CAUSEF_IP6)
loongson3_ipi_interrupt(NULL);
#endif
else if (pending & CAUSEF_IP3)
ht_irqdispatch();
else if (pending & CAUSEF_IP2)
@ -45,10 +49,26 @@ static inline void mask_loongson_irq(struct irq_data *d)
{
clear_c0_status(0x100 << (d->irq - MIPS_CPU_IRQ_BASE));
irq_disable_hazard();
/* Workaround: UART IRQ may deliver to any core */
if (d->irq == LOONGSON_UART_IRQ) {
int cpu = smp_processor_id();
LOONGSON_INT_ROUTER_INTENCLR = 1 << 10;
LOONGSON_INT_ROUTER_LPC = 0x10 + (1<<cpu);
}
}
static inline void unmask_loongson_irq(struct irq_data *d)
{
/* Workaround: UART IRQ may deliver to any core */
if (d->irq == LOONGSON_UART_IRQ) {
int cpu = smp_processor_id();
LOONGSON_INT_ROUTER_INTENSET = 1 << 10;
LOONGSON_INT_ROUTER_LPC = 0x10 + (1<<cpu);
}
set_c0_status(0x100 << (d->irq - MIPS_CPU_IRQ_BASE));
irq_enable_hazard();
}

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@ -0,0 +1,267 @@
/*
* Copyright (C) 2010, 2011, 2012, Lemote, Inc.
* Author: Chen Huacai, chenhc@lemote.com
*
* 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; 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.
*
*/
#include <linux/init.h>
#include <linux/cpu.h>
#include <linux/sched.h>
#include <linux/smp.h>
#include <linux/cpufreq.h>
#include <asm/processor.h>
#include <asm/time.h>
#include <asm/clock.h>
#include <asm/tlbflush.h>
#include <loongson.h>
#include "smp.h"
/* read a 32bit value from ipi register */
#define loongson3_ipi_read32(addr) readl(addr)
/* read a 64bit value from ipi register */
#define loongson3_ipi_read64(addr) readq(addr)
/* write a 32bit value to ipi register */
#define loongson3_ipi_write32(action, addr) \
do { \
writel(action, addr); \
__wbflush(); \
} while (0)
/* write a 64bit value to ipi register */
#define loongson3_ipi_write64(action, addr) \
do { \
writeq(action, addr); \
__wbflush(); \
} while (0)
static void *ipi_set0_regs[] = {
(void *)(SMP_CORE_GROUP0_BASE + SMP_CORE0_OFFSET + SET0),
(void *)(SMP_CORE_GROUP0_BASE + SMP_CORE1_OFFSET + SET0),
(void *)(SMP_CORE_GROUP0_BASE + SMP_CORE2_OFFSET + SET0),
(void *)(SMP_CORE_GROUP0_BASE + SMP_CORE3_OFFSET + SET0),
(void *)(SMP_CORE_GROUP1_BASE + SMP_CORE0_OFFSET + SET0),
(void *)(SMP_CORE_GROUP1_BASE + SMP_CORE1_OFFSET + SET0),
(void *)(SMP_CORE_GROUP1_BASE + SMP_CORE2_OFFSET + SET0),
(void *)(SMP_CORE_GROUP1_BASE + SMP_CORE3_OFFSET + SET0),
(void *)(SMP_CORE_GROUP2_BASE + SMP_CORE0_OFFSET + SET0),
(void *)(SMP_CORE_GROUP2_BASE + SMP_CORE1_OFFSET + SET0),
(void *)(SMP_CORE_GROUP2_BASE + SMP_CORE2_OFFSET + SET0),
(void *)(SMP_CORE_GROUP2_BASE + SMP_CORE3_OFFSET + SET0),
(void *)(SMP_CORE_GROUP3_BASE + SMP_CORE0_OFFSET + SET0),
(void *)(SMP_CORE_GROUP3_BASE + SMP_CORE1_OFFSET + SET0),
(void *)(SMP_CORE_GROUP3_BASE + SMP_CORE2_OFFSET + SET0),
(void *)(SMP_CORE_GROUP3_BASE + SMP_CORE3_OFFSET + SET0),
};
static void *ipi_clear0_regs[] = {
(void *)(SMP_CORE_GROUP0_BASE + SMP_CORE0_OFFSET + CLEAR0),
(void *)(SMP_CORE_GROUP0_BASE + SMP_CORE1_OFFSET + CLEAR0),
(void *)(SMP_CORE_GROUP0_BASE + SMP_CORE2_OFFSET + CLEAR0),
(void *)(SMP_CORE_GROUP0_BASE + SMP_CORE3_OFFSET + CLEAR0),
(void *)(SMP_CORE_GROUP1_BASE + SMP_CORE0_OFFSET + CLEAR0),
(void *)(SMP_CORE_GROUP1_BASE + SMP_CORE1_OFFSET + CLEAR0),
(void *)(SMP_CORE_GROUP1_BASE + SMP_CORE2_OFFSET + CLEAR0),
(void *)(SMP_CORE_GROUP1_BASE + SMP_CORE3_OFFSET + CLEAR0),
(void *)(SMP_CORE_GROUP2_BASE + SMP_CORE0_OFFSET + CLEAR0),
(void *)(SMP_CORE_GROUP2_BASE + SMP_CORE1_OFFSET + CLEAR0),
(void *)(SMP_CORE_GROUP2_BASE + SMP_CORE2_OFFSET + CLEAR0),
(void *)(SMP_CORE_GROUP2_BASE + SMP_CORE3_OFFSET + CLEAR0),
(void *)(SMP_CORE_GROUP3_BASE + SMP_CORE0_OFFSET + CLEAR0),
(void *)(SMP_CORE_GROUP3_BASE + SMP_CORE1_OFFSET + CLEAR0),
(void *)(SMP_CORE_GROUP3_BASE + SMP_CORE2_OFFSET + CLEAR0),
(void *)(SMP_CORE_GROUP3_BASE + SMP_CORE3_OFFSET + CLEAR0),
};
static void *ipi_status0_regs[] = {
(void *)(SMP_CORE_GROUP0_BASE + SMP_CORE0_OFFSET + STATUS0),
(void *)(SMP_CORE_GROUP0_BASE + SMP_CORE1_OFFSET + STATUS0),
(void *)(SMP_CORE_GROUP0_BASE + SMP_CORE2_OFFSET + STATUS0),
(void *)(SMP_CORE_GROUP0_BASE + SMP_CORE3_OFFSET + STATUS0),
(void *)(SMP_CORE_GROUP1_BASE + SMP_CORE0_OFFSET + STATUS0),
(void *)(SMP_CORE_GROUP1_BASE + SMP_CORE1_OFFSET + STATUS0),
(void *)(SMP_CORE_GROUP1_BASE + SMP_CORE2_OFFSET + STATUS0),
(void *)(SMP_CORE_GROUP1_BASE + SMP_CORE3_OFFSET + STATUS0),
(void *)(SMP_CORE_GROUP2_BASE + SMP_CORE0_OFFSET + STATUS0),
(void *)(SMP_CORE_GROUP2_BASE + SMP_CORE1_OFFSET + STATUS0),
(void *)(SMP_CORE_GROUP2_BASE + SMP_CORE2_OFFSET + STATUS0),
(void *)(SMP_CORE_GROUP2_BASE + SMP_CORE3_OFFSET + STATUS0),
(void *)(SMP_CORE_GROUP3_BASE + SMP_CORE0_OFFSET + STATUS0),
(void *)(SMP_CORE_GROUP3_BASE + SMP_CORE1_OFFSET + STATUS0),
(void *)(SMP_CORE_GROUP3_BASE + SMP_CORE2_OFFSET + STATUS0),
(void *)(SMP_CORE_GROUP3_BASE + SMP_CORE3_OFFSET + STATUS0),
};
static void *ipi_en0_regs[] = {
(void *)(SMP_CORE_GROUP0_BASE + SMP_CORE0_OFFSET + EN0),
(void *)(SMP_CORE_GROUP0_BASE + SMP_CORE1_OFFSET + EN0),
(void *)(SMP_CORE_GROUP0_BASE + SMP_CORE2_OFFSET + EN0),
(void *)(SMP_CORE_GROUP0_BASE + SMP_CORE3_OFFSET + EN0),
(void *)(SMP_CORE_GROUP1_BASE + SMP_CORE0_OFFSET + EN0),
(void *)(SMP_CORE_GROUP1_BASE + SMP_CORE1_OFFSET + EN0),
(void *)(SMP_CORE_GROUP1_BASE + SMP_CORE2_OFFSET + EN0),
(void *)(SMP_CORE_GROUP1_BASE + SMP_CORE3_OFFSET + EN0),
(void *)(SMP_CORE_GROUP2_BASE + SMP_CORE0_OFFSET + EN0),
(void *)(SMP_CORE_GROUP2_BASE + SMP_CORE1_OFFSET + EN0),
(void *)(SMP_CORE_GROUP2_BASE + SMP_CORE2_OFFSET + EN0),
(void *)(SMP_CORE_GROUP2_BASE + SMP_CORE3_OFFSET + EN0),
(void *)(SMP_CORE_GROUP3_BASE + SMP_CORE0_OFFSET + EN0),
(void *)(SMP_CORE_GROUP3_BASE + SMP_CORE1_OFFSET + EN0),
(void *)(SMP_CORE_GROUP3_BASE + SMP_CORE2_OFFSET + EN0),
(void *)(SMP_CORE_GROUP3_BASE + SMP_CORE3_OFFSET + EN0),
};
static void *ipi_mailbox_buf[] = {
(void *)(SMP_CORE_GROUP0_BASE + SMP_CORE0_OFFSET + BUF),
(void *)(SMP_CORE_GROUP0_BASE + SMP_CORE1_OFFSET + BUF),
(void *)(SMP_CORE_GROUP0_BASE + SMP_CORE2_OFFSET + BUF),
(void *)(SMP_CORE_GROUP0_BASE + SMP_CORE3_OFFSET + BUF),
(void *)(SMP_CORE_GROUP1_BASE + SMP_CORE0_OFFSET + BUF),
(void *)(SMP_CORE_GROUP1_BASE + SMP_CORE1_OFFSET + BUF),
(void *)(SMP_CORE_GROUP1_BASE + SMP_CORE2_OFFSET + BUF),
(void *)(SMP_CORE_GROUP1_BASE + SMP_CORE3_OFFSET + BUF),
(void *)(SMP_CORE_GROUP2_BASE + SMP_CORE0_OFFSET + BUF),
(void *)(SMP_CORE_GROUP2_BASE + SMP_CORE1_OFFSET + BUF),
(void *)(SMP_CORE_GROUP2_BASE + SMP_CORE2_OFFSET + BUF),
(void *)(SMP_CORE_GROUP2_BASE + SMP_CORE3_OFFSET + BUF),
(void *)(SMP_CORE_GROUP3_BASE + SMP_CORE0_OFFSET + BUF),
(void *)(SMP_CORE_GROUP3_BASE + SMP_CORE1_OFFSET + BUF),
(void *)(SMP_CORE_GROUP3_BASE + SMP_CORE2_OFFSET + BUF),
(void *)(SMP_CORE_GROUP3_BASE + SMP_CORE3_OFFSET + BUF),
};
/*
* Simple enough, just poke the appropriate ipi register
*/
static void loongson3_send_ipi_single(int cpu, unsigned int action)
{
loongson3_ipi_write32((u32)action, ipi_set0_regs[cpu]);
}
static void
loongson3_send_ipi_mask(const struct cpumask *mask, unsigned int action)
{
unsigned int i;
for_each_cpu(i, mask)
loongson3_ipi_write32((u32)action, ipi_set0_regs[i]);
}
void loongson3_ipi_interrupt(struct pt_regs *regs)
{
int cpu = smp_processor_id();
unsigned int action;
/* Load the ipi register to figure out what we're supposed to do */
action = loongson3_ipi_read32(ipi_status0_regs[cpu]);
/* Clear the ipi register to clear the interrupt */
loongson3_ipi_write32((u32)action, ipi_clear0_regs[cpu]);
if (action & SMP_RESCHEDULE_YOURSELF)
scheduler_ipi();
if (action & SMP_CALL_FUNCTION)
smp_call_function_interrupt();
}
/*
* SMP init and finish on secondary CPUs
*/
static void loongson3_init_secondary(void)
{
int i;
unsigned int imask = STATUSF_IP7 | STATUSF_IP6 |
STATUSF_IP3 | STATUSF_IP2;
/* Set interrupt mask, but don't enable */
change_c0_status(ST0_IM, imask);
for (i = 0; i < loongson_sysconf.nr_cpus; i++)
loongson3_ipi_write32(0xffffffff, ipi_en0_regs[i]);
}
static void loongson3_smp_finish(void)
{
write_c0_compare(read_c0_count() + mips_hpt_frequency/HZ);
local_irq_enable();
loongson3_ipi_write64(0,
(void *)(ipi_mailbox_buf[smp_processor_id()]+0x0));
pr_info("CPU#%d finished, CP0_ST=%x\n",
smp_processor_id(), read_c0_status());
}
static void __init loongson3_smp_setup(void)
{
int i, num;
init_cpu_possible(cpu_none_mask);
set_cpu_possible(0, true);
__cpu_number_map[0] = 0;
__cpu_logical_map[0] = 0;
/* For unified kernel, NR_CPUS is the maximum possible value,
* loongson_sysconf.nr_cpus is the really present value */
for (i = 1, num = 0; i < loongson_sysconf.nr_cpus; i++) {
set_cpu_possible(i, true);
__cpu_number_map[i] = ++num;
__cpu_logical_map[num] = i;
}
pr_info("Detected %i available secondary CPU(s)\n", num);
}
static void __init loongson3_prepare_cpus(unsigned int max_cpus)
{
}
/*
* Setup the PC, SP, and GP of a secondary processor and start it runing!
*/
static void loongson3_boot_secondary(int cpu, struct task_struct *idle)
{
unsigned long startargs[4];
pr_info("Booting CPU#%d...\n", cpu);
/* startargs[] are initial PC, SP and GP for secondary CPU */
startargs[0] = (unsigned long)&smp_bootstrap;
startargs[1] = (unsigned long)__KSTK_TOS(idle);
startargs[2] = (unsigned long)task_thread_info(idle);
startargs[3] = 0;
pr_debug("CPU#%d, func_pc=%lx, sp=%lx, gp=%lx\n",
cpu, startargs[0], startargs[1], startargs[2]);
loongson3_ipi_write64(startargs[3], (void *)(ipi_mailbox_buf[cpu]+0x18));
loongson3_ipi_write64(startargs[2], (void *)(ipi_mailbox_buf[cpu]+0x10));
loongson3_ipi_write64(startargs[1], (void *)(ipi_mailbox_buf[cpu]+0x8));
loongson3_ipi_write64(startargs[0], (void *)(ipi_mailbox_buf[cpu]+0x0));
}
/*
* Final cleanup after all secondaries booted
*/
static void __init loongson3_cpus_done(void)
{
}
struct plat_smp_ops loongson3_smp_ops = {
.send_ipi_single = loongson3_send_ipi_single,
.send_ipi_mask = loongson3_send_ipi_mask,
.init_secondary = loongson3_init_secondary,
.smp_finish = loongson3_smp_finish,
.cpus_done = loongson3_cpus_done,
.boot_secondary = loongson3_boot_secondary,
.smp_setup = loongson3_smp_setup,
.prepare_cpus = loongson3_prepare_cpus,
};

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@ -0,0 +1,29 @@
#ifndef __LOONGSON_SMP_H_
#define __LOONGSON_SMP_H_
/* for Loongson-3A smp support */
/* 4 groups(nodes) in maximum in numa case */
#define SMP_CORE_GROUP0_BASE 0x900000003ff01000
#define SMP_CORE_GROUP1_BASE 0x900010003ff01000
#define SMP_CORE_GROUP2_BASE 0x900020003ff01000
#define SMP_CORE_GROUP3_BASE 0x900030003ff01000
/* 4 cores in each group(node) */
#define SMP_CORE0_OFFSET 0x000
#define SMP_CORE1_OFFSET 0x100
#define SMP_CORE2_OFFSET 0x200
#define SMP_CORE3_OFFSET 0x300
/* ipi registers offsets */
#define STATUS0 0x00
#define EN0 0x04
#define SET0 0x08
#define CLEAR0 0x0c
#define STATUS1 0x10
#define MASK1 0x14
#define SET1 0x18
#define CLEAR1 0x1c
#define BUF 0x20
#endif