ARCv2: SMP: Support ARConnect (MCIP) for Inter-Core-Interrupts et al

Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
This commit is contained in:
Vineet Gupta 2014-09-10 19:05:38 +05:30
parent 173eaafaed
commit 82fea5a1bb
7 changed files with 230 additions and 8 deletions

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@ -160,12 +160,12 @@ config CPU_BIG_ENDIAN
Build kernel for Big Endian Mode of ARC CPU
config SMP
bool "Symmetric Multi-Processing (Incomplete)"
bool "Symmetric Multi-Processing"
default n
select ARC_HAS_COH_CACHES if ISA_ARCV2
select ARC_MCIP if ISA_ARCV2
help
This enables support for systems with more than one CPU. If you have
a system with only one CPU, say N. If you have a system with more
than one CPU, say Y.
This enables support for systems with more than one CPU.
if SMP
@ -175,13 +175,20 @@ config ARC_HAS_COH_CACHES
config ARC_HAS_REENTRANT_IRQ_LV2
def_bool n
endif #SMP
config ARC_MCIP
bool "ARConnect Multicore IP (MCIP) Support "
depends on ISA_ARCV2
help
This IP block enables SMP in ARC-HS38 cores.
It provides for cross-core interrupts, multi-core debug
hardware semaphores, shared memory,....
config NR_CPUS
int "Maximum number of CPUs (2-4096)"
range 2 4096
depends on SMP
default "2"
default "4"
endif #SMP
menuconfig ARC_CACHE
bool "Enable Cache Support"

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@ -19,6 +19,7 @@
#else
#define TIMER0_IRQ 16
#define TIMER1_IRQ 17
#define IPI_IRQ 19
#endif
#include <linux/interrupt.h>

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@ -0,0 +1,91 @@
/*
* ARConnect IP Support (Multi core enabler: Cross core IPI, RTC ...)
*
* Copyright (C) 2014-15 Synopsys, Inc. (www.synopsys.com)
*
* 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.
*/
#ifndef __ASM_MCIP_H
#define __ASM_MCIP_H
#ifdef CONFIG_ISA_ARCV2
#include <asm/arcregs.h>
#define ARC_REG_MCIP_BCR 0x0d0
#define ARC_REG_MCIP_CMD 0x600
#define ARC_REG_MCIP_WDATA 0x601
#define ARC_REG_MCIP_READBACK 0x602
struct mcip_cmd {
#ifdef CONFIG_CPU_BIG_ENDIAN
unsigned int pad:8, param:16, cmd:8;
#else
unsigned int cmd:8, param:16, pad:8;
#endif
#define CMD_INTRPT_GENERATE_IRQ 0x01
#define CMD_INTRPT_GENERATE_ACK 0x02
#define CMD_INTRPT_READ_STATUS 0x03
#define CMD_INTRPT_CHECK_SOURCE 0x04
/* Semaphore Commands */
#define CMD_SEMA_CLAIM_AND_READ 0x11
#define CMD_SEMA_RELEASE 0x12
#define CMD_DEBUG_SET_MASK 0x34
#define CMD_DEBUG_SET_SELECT 0x36
#define CMD_IDU_ENABLE 0x71
#define CMD_IDU_DISABLE 0x72
#define CMD_IDU_SET_MODE 0x74
#define CMD_IDU_SET_DEST 0x76
#define CMD_IDU_SET_MASK 0x7C
#define IDU_M_TRIG_LEVEL 0x0
#define IDU_M_TRIG_EDGE 0x1
#define IDU_M_DISTRI_RR 0x0
#define IDU_M_DISTRI_DEST 0x2
};
/*
* MCIP programming model
*
* - Simple commands write {cmd:8,param:16} to MCIP_CMD aux reg
* (param could be irq, common_irq, core_id ...)
* - More involved commands setup MCIP_WDATA with cmd specific data
* before invoking the simple command
*/
static inline void __mcip_cmd(unsigned int cmd, unsigned int param)
{
struct mcip_cmd buf;
buf.pad = 0;
buf.cmd = cmd;
buf.param = param;
WRITE_AUX(ARC_REG_MCIP_CMD, buf);
}
/*
* Setup additional data for a cmd
* Callers need to lock to ensure atomicity
*/
static inline void __mcip_cmd_data(unsigned int cmd, unsigned int param,
unsigned int data)
{
write_aux_reg(ARC_REG_MCIP_WDATA, data);
__mcip_cmd(cmd, param);
}
extern void mcip_init_early_smp(void);
extern void mcip_init_smp(unsigned int cpu);
#endif
#endif

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@ -15,6 +15,7 @@ obj-$(CONFIG_ISA_ARCV2) += entry-arcv2.o intc-arcv2.o
obj-$(CONFIG_MODULES) += arcksyms.o module.o
obj-$(CONFIG_SMP) += smp.o
obj-$(CONFIG_ARC_MCIP) += mcip.o
obj-$(CONFIG_ARC_DW2_UNWIND) += unwind.o
obj-$(CONFIG_KPROBES) += kprobes.o
obj-$(CONFIG_ARC_EMUL_UNALIGNED) += unaligned.o

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@ -107,7 +107,7 @@ static struct irq_chip arcv2_irq_chip = {
static int arcv2_irq_map(struct irq_domain *d, unsigned int irq,
irq_hw_number_t hw)
{
if (irq == TIMER0_IRQ)
if (irq == TIMER0_IRQ || irq == IPI_IRQ)
irq_set_chip_and_handler(irq, &arcv2_irq_chip, handle_percpu_irq);
else
irq_set_chip_and_handler(irq, &arcv2_irq_chip, handle_level_irq);

117
arch/arc/kernel/mcip.c Normal file
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@ -0,0 +1,117 @@
/*
* ARC ARConnect (MultiCore IP) support (formerly known as MCIP)
*
* Copyright (C) 2013 Synopsys, Inc. (www.synopsys.com)
*
* 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/smp.h>
#include <linux/irq.h>
#include <linux/spinlock.h>
#include <asm/mcip.h>
static char smp_cpuinfo_buf[128];
static DEFINE_RAW_SPINLOCK(mcip_lock);
/*
* Any SMP specific init any CPU does when it comes up.
* Here we setup the CPU to enable Inter-Processor-Interrupts
* Called for each CPU
* -Master : init_IRQ()
* -Other(s) : start_kernel_secondary()
*/
void mcip_init_smp(unsigned int cpu)
{
smp_ipi_irq_setup(cpu, IPI_IRQ);
}
static void mcip_ipi_send(int cpu)
{
unsigned long flags;
raw_spin_lock_irqsave(&mcip_lock, flags);
__mcip_cmd(CMD_INTRPT_GENERATE_IRQ, cpu);
raw_spin_unlock_irqrestore(&mcip_lock, flags);
}
static void mcip_ipi_clear(int irq)
{
unsigned int cpu;
unsigned long flags;
raw_spin_lock_irqsave(&mcip_lock, flags);
/* Who sent the IPI */
__mcip_cmd(CMD_INTRPT_CHECK_SOURCE, 0);
cpu = read_aux_reg(ARC_REG_MCIP_READBACK); /* 1,2,4,8... */
__mcip_cmd(CMD_INTRPT_GENERATE_ACK, __ffs(cpu)); /* 0,1,2,3... */
raw_spin_unlock_irqrestore(&mcip_lock, flags);
}
volatile int wake_flag;
static void mcip_wakeup_cpu(int cpu, unsigned long pc)
{
BUG_ON(cpu == 0);
wake_flag = cpu;
}
void arc_platform_smp_wait_to_boot(int cpu)
{
while (wake_flag != cpu)
;
wake_flag = 0;
__asm__ __volatile__("j @first_lines_of_secondary \n");
}
struct plat_smp_ops plat_smp_ops = {
.info = smp_cpuinfo_buf,
.cpu_kick = mcip_wakeup_cpu,
.ipi_send = mcip_ipi_send,
.ipi_clear = mcip_ipi_clear,
};
void mcip_init_early_smp(void)
{
#define IS_AVAIL1(var, str) ((var) ? str : "")
struct mcip_bcr {
#ifdef CONFIG_CPU_BIG_ENDIAN
unsigned int pad3:8,
idu:1, llm:1, num_cores:6,
iocoh:1, grtc:1, dbg:1, pad2:1,
msg:1, sem:1, ipi:1, pad:1,
ver:8;
#else
unsigned int ver:8,
pad:1, ipi:1, sem:1, msg:1,
pad2:1, dbg:1, grtc:1, iocoh:1,
num_cores:6, llm:1, idu:1,
pad3:8;
#endif
} mp;
READ_BCR(ARC_REG_MCIP_BCR, mp);
sprintf(smp_cpuinfo_buf,
"Extn [SMP]\t: ARConnect (v%d): %d cores with %s%s%s%s\n",
mp.ver, mp.num_cores,
IS_AVAIL1(mp.ipi, "IPI "),
IS_AVAIL1(mp.idu, "IDU "),
IS_AVAIL1(mp.dbg, "DEBUG "),
IS_AVAIL1(mp.grtc, "GRTC"));
if (mp.dbg) {
__mcip_cmd_data(CMD_DEBUG_SET_SELECT, 0, 0xf);
__mcip_cmd_data(CMD_DEBUG_SET_MASK, 0xf, 0xf);
}
}

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@ -10,6 +10,7 @@
#include <linux/init.h>
#include <asm/mach_desc.h>
#include <asm/mcip.h>
/*----------------------- Machine Descriptions ------------------------------
*
@ -27,4 +28,8 @@ static const char *simulation_compat[] __initconst = {
MACHINE_START(SIMULATION, "simulation")
.dt_compat = simulation_compat,
#ifdef CONFIG_ARC_MCIP
.init_early = mcip_init_early_smp,
.init_smp = mcip_init_smp,
#endif
MACHINE_END