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RISC-V: Treat IPIs as normal Linux IRQs

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Currently, the RISC-V kernel provides arch specific hooks (i.e.
struct riscv_ipi_ops) to register IPI handling methods. The stats
gathering of IPIs is also arch specific in the RISC-V kernel.

Other architectures (such as ARM, ARM64, and MIPS) have moved away
from custom arch specific IPI handling methods. Currently, these
architectures have Linux irqchip drivers providing a range of Linux
IRQ numbers to be used as IPIs and IPI triggering is done using
generic IPI APIs. This approach allows architectures to treat IPIs
as normal Linux IRQs and IPI stats gathering is done by the generic
Linux IRQ subsystem.

We extend the RISC-V IPI handling as-per above approach so that arch
specific IPI handling methods (struct riscv_ipi_ops) can be removed
and the IPI handling is done through the Linux IRQ subsystem.

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230328035223.1480939-4-apatel@ventanamicro.com
This commit is contained in:
Anup Patel 2023-03-28 09:22:19 +05:30 committed by Marc Zyngier
parent 0c60a31ce6
commit 832f15f426
13 changed files with 291 additions and 247 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
arch/riscv/Kconfig
View File

@ -63,6 +63,8 @@ config RISCV
select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO
select GENERIC_IDLE_POLL_SETUP
select GENERIC_IOREMAP if MMU
select GENERIC_IRQ_IPI if SMP
select GENERIC_IRQ_IPI_MUX if SMP
select GENERIC_IRQ_MULTI_HANDLER
select GENERIC_IRQ_SHOW
select GENERIC_IRQ_SHOW_LEVEL

9
arch/riscv/include/asm/sbi.h
View File

@ -271,8 +271,7 @@ long sbi_get_marchid(void);
long sbi_get_mimpid(void);
void sbi_set_timer(uint64_t stime_value);
void sbi_shutdown(void);
void sbi_clear_ipi(void);
int sbi_send_ipi(const struct cpumask *cpu_mask);
void sbi_send_ipi(unsigned int cpu);
int sbi_remote_fence_i(const struct cpumask *cpu_mask);
int sbi_remote_sfence_vma(const struct cpumask *cpu_mask,
unsigned long start,
@ -335,4 +334,10 @@ unsigned long riscv_cached_mvendorid(unsigned int cpu_id);
unsigned long riscv_cached_marchid(unsigned int cpu_id);
unsigned long riscv_cached_mimpid(unsigned int cpu_id);
#if IS_ENABLED(CONFIG_SMP) && IS_ENABLED(CONFIG_RISCV_SBI)
void sbi_ipi_init(void);
#else
static inline void sbi_ipi_init(void) { }
#endif
#endif /* _ASM_RISCV_SBI_H */

35
arch/riscv/include/asm/smp.h
View File

@ -15,11 +15,6 @@
struct seq_file;
extern unsigned long boot_cpu_hartid;
struct riscv_ipi_ops {
void (*ipi_inject)(const struct cpumask *target);
void (*ipi_clear)(void);
};
#ifdef CONFIG_SMP
/*
* Mapping between linux logical cpu index and hartid.
@ -33,9 +28,6 @@ void show_ipi_stats(struct seq_file *p, int prec);
/* SMP initialization hook for setup_arch */
void __init setup_smp(void);
/* Called from C code, this handles an IPI. */
void handle_IPI(struct pt_regs *regs);
/* Hook for the generic smp_call_function_many() routine. */
void arch_send_call_function_ipi_mask(struct cpumask *mask);
@ -44,11 +36,17 @@ void arch_send_call_function_single_ipi(int cpu);
int riscv_hartid_to_cpuid(unsigned long hartid);
/* Set custom IPI operations */
void riscv_set_ipi_ops(const struct riscv_ipi_ops *ops);
/* Enable IPI for CPU hotplug */
void riscv_ipi_enable(void);
/* Clear IPI for current CPU */
void riscv_clear_ipi(void);
/* Disable IPI for CPU hotplug */
void riscv_ipi_disable(void);
/* Check if IPI interrupt numbers are available */
bool riscv_ipi_have_virq_range(void);
/* Set the IPI interrupt numbers for arch (called by irqchip drivers) */
void riscv_ipi_set_virq_range(int virq, int nr);
/* Check other CPUs stop or not */
bool smp_crash_stop_failed(void);
@ -85,11 +83,20 @@ static inline unsigned long cpuid_to_hartid_map(int cpu)
return boot_cpu_hartid;
}
static inline void riscv_set_ipi_ops(const struct riscv_ipi_ops *ops)
static inline void riscv_ipi_enable(void)
{
}
static inline void riscv_clear_ipi(void)
static inline void riscv_ipi_disable(void)
{
}
static inline bool riscv_ipi_have_virq_range(void)
{
return false;
}
static inline void riscv_ipi_set_virq_range(int virq, int nr)
{
}

1
arch/riscv/kernel/Makefile
View File

@ -74,6 +74,7 @@ obj-$(CONFIG_PERF_EVENTS) += perf_callchain.o
obj-$(CONFIG_HAVE_PERF_REGS) += perf_regs.o
obj-$(CONFIG_RISCV_SBI) += sbi.o
ifeq ($(CONFIG_RISCV_SBI), y)
obj-$(CONFIG_SMP) += sbi-ipi.o
obj-$(CONFIG_SMP) += cpu_ops_sbi.o
endif
obj-$(CONFIG_HOTPLUG_CPU) += cpu-hotplug.o

3
arch/riscv/kernel/cpu-hotplug.c
View File

@ -13,7 +13,7 @@
#include <asm/irq.h>
#include <asm/cpu_ops.h>
#include <asm/numa.h>
#include <asm/sbi.h>
#include <asm/smp.h>
bool cpu_has_hotplug(unsigned int cpu)
{
@ -43,6 +43,7 @@ int __cpu_disable(void)
remove_cpu_topology(cpu);
numa_remove_cpu(cpu);
set_cpu_online(cpu, false);
riscv_ipi_disable();
irq_migrate_all_off_this_cpu();
return ret;

3
arch/riscv/kernel/irq.c
View File

@ -10,7 +10,7 @@
#include <linux/irqdomain.h>
#include <linux/module.h>
#include <linux/seq_file.h>
#include <asm/smp.h>
#include <asm/sbi.h>
static struct fwnode_handle *(*__get_intc_node)(void);
@ -39,4 +39,5 @@ void __init init_IRQ(void)
irqchip_init();
if (!handle_arch_irq)
panic("No interrupt controller found.");
sbi_ipi_init();
}

77
arch/riscv/kernel/sbi-ipi.c Normal file
View File

@ -0,0 +1,77 @@
// SPDX-License-Identifier: GPL-2.0-only
/*
* Multiplex several IPIs over a single HW IPI.
*
* Copyright (c) 2022 Ventana Micro Systems Inc.
*/
#define pr_fmt(fmt) "riscv: " fmt
#include <linux/cpu.h>
#include <linux/init.h>
#include <linux/irq.h>
#include <linux/irqchip/chained_irq.h>
#include <linux/irqdomain.h>
#include <asm/sbi.h>
static int sbi_ipi_virq;
static void sbi_ipi_handle(struct irq_desc *desc)
{
struct irq_chip *chip = irq_desc_get_chip(desc);
chained_irq_enter(chip, desc);
csr_clear(CSR_IP, IE_SIE);
ipi_mux_process();
chained_irq_exit(chip, desc);
}
static int sbi_ipi_starting_cpu(unsigned int cpu)
{
enable_percpu_irq(sbi_ipi_virq, irq_get_trigger_type(sbi_ipi_virq));
return 0;
}
void __init sbi_ipi_init(void)
{
int virq;
struct irq_domain *domain;
if (riscv_ipi_have_virq_range())
return;
domain = irq_find_matching_fwnode(riscv_get_intc_hwnode(),
DOMAIN_BUS_ANY);
if (!domain) {
pr_err("unable to find INTC IRQ domain\n");
return;
}
sbi_ipi_virq = irq_create_mapping(domain, RV_IRQ_SOFT);
if (!sbi_ipi_virq) {
pr_err("unable to create INTC IRQ mapping\n");
return;
}
virq = ipi_mux_create(BITS_PER_BYTE, sbi_send_ipi);
if (virq <= 0) {
pr_err("unable to create muxed IPIs\n");
irq_dispose_mapping(sbi_ipi_virq);
return;
}
irq_set_chained_handler(sbi_ipi_virq, sbi_ipi_handle);
/*
* Don't disable IPI when CPU goes offline because
* the masking/unmasking of virtual IPIs is done
* via generic IPI-Mux
*/
cpuhp_setup_state(CPUHP_AP_ONLINE_DYN,
"irqchip/sbi-ipi:starting",
sbi_ipi_starting_cpu, NULL);
riscv_ipi_set_virq_range(virq, BITS_PER_BYTE);
pr_info("providing IPIs using SBI IPI extension\n");
}

106
arch/riscv/kernel/sbi.c
View File

@ -17,7 +17,7 @@ unsigned long sbi_spec_version __ro_after_init = SBI_SPEC_VERSION_DEFAULT;
EXPORT_SYMBOL(sbi_spec_version);
static void (*__sbi_set_timer)(uint64_t stime) __ro_after_init;
static int (*__sbi_send_ipi)(const struct cpumask *cpu_mask) __ro_after_init;
static void (*__sbi_send_ipi)(unsigned int cpu) __ro_after_init;
static int (*__sbi_rfence)(int fid, const struct cpumask *cpu_mask,
unsigned long start, unsigned long size,
unsigned long arg4, unsigned long arg5) __ro_after_init;
@ -130,17 +130,6 @@ void sbi_shutdown(void)
}
EXPORT_SYMBOL(sbi_shutdown);
/**
* sbi_clear_ipi() - Clear any pending IPIs for the calling hart.
*
* Return: None
*/
void sbi_clear_ipi(void)
{
sbi_ecall(SBI_EXT_0_1_CLEAR_IPI, 0, 0, 0, 0, 0, 0, 0);
}
EXPORT_SYMBOL(sbi_clear_ipi);
/**
* __sbi_set_timer_v01() - Program the timer for next timer event.
* @stime_value: The value after which next timer event should fire.
@ -157,17 +146,12 @@ static void __sbi_set_timer_v01(uint64_t stime_value)
#endif
}
static int __sbi_send_ipi_v01(const struct cpumask *cpu_mask)
static void __sbi_send_ipi_v01(unsigned int cpu)
{
unsigned long hart_mask;
if (!cpu_mask || cpumask_empty(cpu_mask))
cpu_mask = cpu_online_mask;
hart_mask = __sbi_v01_cpumask_to_hartmask(cpu_mask);
unsigned long hart_mask =
__sbi_v01_cpumask_to_hartmask(cpumask_of(cpu));
sbi_ecall(SBI_EXT_0_1_SEND_IPI, 0, (unsigned long)(&hart_mask),
0, 0, 0, 0, 0);
return 0;
}
static int __sbi_rfence_v01(int fid, const struct cpumask *cpu_mask,
@ -216,12 +200,10 @@ static void __sbi_set_timer_v01(uint64_t stime_value)
sbi_major_version(), sbi_minor_version());
}
static int __sbi_send_ipi_v01(const struct cpumask *cpu_mask)
static void __sbi_send_ipi_v01(unsigned int cpu)
{
pr_warn("IPI extension is not available in SBI v%lu.%lu\n",
sbi_major_version(), sbi_minor_version());
return 0;
}
static int __sbi_rfence_v01(int fid, const struct cpumask *cpu_mask,
@ -248,55 +230,18 @@ static void __sbi_set_timer_v02(uint64_t stime_value)
#endif
}
static int __sbi_send_ipi_v02(const struct cpumask *cpu_mask)
static void __sbi_send_ipi_v02(unsigned int cpu)
{
unsigned long hartid, cpuid, hmask = 0, hbase = 0, htop = 0;
struct sbiret ret = {0};
int result;
struct sbiret ret = {0};
if (!cpu_mask || cpumask_empty(cpu_mask))
cpu_mask = cpu_online_mask;
for_each_cpu(cpuid, cpu_mask) {
hartid = cpuid_to_hartid_map(cpuid);
if (hmask) {
if (hartid + BITS_PER_LONG <= htop ||
hbase + BITS_PER_LONG <= hartid) {
ret = sbi_ecall(SBI_EXT_IPI,
SBI_EXT_IPI_SEND_IPI, hmask,
hbase, 0, 0, 0, 0);
if (ret.error)
goto ecall_failed;
hmask = 0;
} else if (hartid < hbase) {
/* shift the mask to fit lower hartid */
hmask <<= hbase - hartid;
hbase = hartid;
}
}
if (!hmask) {
hbase = hartid;
htop = hartid;
} else if (hartid > htop) {
htop = hartid;
}
hmask |= BIT(hartid - hbase);
ret = sbi_ecall(SBI_EXT_IPI, SBI_EXT_IPI_SEND_IPI,
1UL, cpuid_to_hartid_map(cpu), 0, 0, 0, 0);
if (ret.error) {
result = sbi_err_map_linux_errno(ret.error);
pr_err("%s: hbase = [%lu] failed (error [%d])\n",
__func__, cpuid_to_hartid_map(cpu), result);
}
if (hmask) {
ret = sbi_ecall(SBI_EXT_IPI, SBI_EXT_IPI_SEND_IPI,
hmask, hbase, 0, 0, 0, 0);
if (ret.error)
goto ecall_failed;
}
return 0;
ecall_failed:
result = sbi_err_map_linux_errno(ret.error);
pr_err("%s: hbase = [%lu] hmask = [0x%lx] failed (error [%d])\n",
__func__, hbase, hmask, result);
return result;
}
static int __sbi_rfence_v02_call(unsigned long fid, unsigned long hmask,
@ -410,13 +355,11 @@ void sbi_set_timer(uint64_t stime_value)
/**
* sbi_send_ipi() - Send an IPI to any hart.
* @cpu_mask: A cpu mask containing all the target harts.
*
* Return: 0 on success, appropriate linux error code otherwise.
* @cpu: Logical id of the target CPU.
*/
int sbi_send_ipi(const struct cpumask *cpu_mask)
void sbi_send_ipi(unsigned int cpu)
{
return __sbi_send_ipi(cpu_mask);
__sbi_send_ipi(cpu);
}
EXPORT_SYMBOL(sbi_send_ipi);
@ -641,21 +584,6 @@ long sbi_get_mimpid(void)
}
EXPORT_SYMBOL_GPL(sbi_get_mimpid);
static void sbi_send_cpumask_ipi(const struct cpumask *target)
{
sbi_send_ipi(target);
}
static void sbi_ipi_clear(void)
{
csr_clear(CSR_IP, IE_SIE);
}
static const struct riscv_ipi_ops sbi_ipi_ops = {
.ipi_inject = sbi_send_cpumask_ipi,
.ipi_clear = sbi_ipi_clear
};
void __init sbi_init(void)
{
int ret;
@ -702,6 +630,4 @@ void __init sbi_init(void)
__sbi_send_ipi = __sbi_send_ipi_v01;
__sbi_rfence = __sbi_rfence_v01;
}
riscv_set_ipi_ops(&sbi_ipi_ops);
}

176
arch/riscv/kernel/smp.c
View File

@ -13,14 +13,15 @@
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/kexec.h>
#include <linux/percpu.h>
#include <linux/profile.h>
#include <linux/smp.h>
#include <linux/sched.h>
#include <linux/seq_file.h>
#include <linux/delay.h>
#include <linux/irq.h>
#include <linux/irq_work.h>
#include <asm/sbi.h>
#include <asm/tlbflush.h>
#include <asm/cacheflush.h>
#include <asm/cpu_ops.h>
@ -44,11 +45,10 @@ void __init smp_setup_processor_id(void)
cpuid_to_hartid_map(0) = boot_cpu_hartid;
}
/* A collection of single bit ipi messages. */
static struct {
unsigned long stats[IPI_MAX] ____cacheline_aligned;
unsigned long bits ____cacheline_aligned;
} ipi_data[NR_CPUS] __cacheline_aligned;
static DEFINE_PER_CPU_READ_MOSTLY(int, ipi_dummy_dev);
static int ipi_virq_base __ro_after_init;
static int nr_ipi __ro_after_init = IPI_MAX;
static struct irq_desc *ipi_desc[IPI_MAX] __read_mostly;
int riscv_hartid_to_cpuid(unsigned long hartid)
{
@ -100,46 +100,14 @@ static inline void ipi_cpu_crash_stop(unsigned int cpu, struct pt_regs *regs)
}
#endif
static const struct riscv_ipi_ops *ipi_ops __ro_after_init;
void riscv_set_ipi_ops(const struct riscv_ipi_ops *ops)
{
ipi_ops = ops;
}
EXPORT_SYMBOL_GPL(riscv_set_ipi_ops);
void riscv_clear_ipi(void)
{
if (ipi_ops && ipi_ops->ipi_clear)
ipi_ops->ipi_clear();
}
EXPORT_SYMBOL_GPL(riscv_clear_ipi);
static void send_ipi_mask(const struct cpumask *mask, enum ipi_message_type op)
{
int cpu;
smp_mb__before_atomic();
for_each_cpu(cpu, mask)
set_bit(op, &ipi_data[cpu].bits);
smp_mb__after_atomic();
if (ipi_ops && ipi_ops->ipi_inject)
ipi_ops->ipi_inject(mask);
else
pr_warn("SMP: IPI inject method not available\n");
__ipi_send_mask(ipi_desc[op], mask);
}
static void send_ipi_single(int cpu, enum ipi_message_type op)
{
smp_mb__before_atomic();
set_bit(op, &ipi_data[cpu].bits);
smp_mb__after_atomic();
if (ipi_ops && ipi_ops->ipi_inject)
ipi_ops->ipi_inject(cpumask_of(cpu));
else
pr_warn("SMP: IPI inject method not available\n");
__ipi_send_mask(ipi_desc[op], cpumask_of(cpu));
}
#ifdef CONFIG_IRQ_WORK
@ -149,59 +117,89 @@ void arch_irq_work_raise(void)
}
#endif
void handle_IPI(struct pt_regs *regs)
static irqreturn_t handle_IPI(int irq, void *data)
{
unsigned int cpu = smp_processor_id();
unsigned long *pending_ipis = &ipi_data[cpu].bits;
unsigned long *stats = ipi_data[cpu].stats;
riscv_clear_ipi();
while (true) {
unsigned long ops;
/* Order bit clearing and data access. */
mb();
ops = xchg(pending_ipis, 0);
if (ops == 0)
return;
if (ops & (1 << IPI_RESCHEDULE)) {
stats[IPI_RESCHEDULE]++;
scheduler_ipi();
}
if (ops & (1 << IPI_CALL_FUNC)) {
stats[IPI_CALL_FUNC]++;
generic_smp_call_function_interrupt();
}
if (ops & (1 << IPI_CPU_STOP)) {
stats[IPI_CPU_STOP]++;
ipi_stop();
}
if (ops & (1 << IPI_CPU_CRASH_STOP)) {
ipi_cpu_crash_stop(cpu, get_irq_regs());
}
if (ops & (1 << IPI_IRQ_WORK)) {
stats[IPI_IRQ_WORK]++;
irq_work_run();
}
int ipi = irq - ipi_virq_base;
switch (ipi) {
case IPI_RESCHEDULE:
scheduler_ipi();
break;
case IPI_CALL_FUNC:
generic_smp_call_function_interrupt();
break;
case IPI_CPU_STOP:
ipi_stop();
break;
case IPI_CPU_CRASH_STOP:
ipi_cpu_crash_stop(smp_processor_id(), get_irq_regs());
break;
case IPI_IRQ_WORK:
irq_work_run();
break;
#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
if (ops & (1 << IPI_TIMER)) {
stats[IPI_TIMER]++;
tick_receive_broadcast();
}
case IPI_TIMER:
tick_receive_broadcast();
break;
#endif
BUG_ON((ops >> IPI_MAX) != 0);
/* Order data access and bit testing. */
mb();
default:
pr_warn("CPU%d: unhandled IPI%d\n", smp_processor_id(), ipi);
break;
}
return IRQ_HANDLED;
}
void riscv_ipi_enable(void)
{
int i;
if (WARN_ON_ONCE(!ipi_virq_base))
return;
for (i = 0; i < nr_ipi; i++)
enable_percpu_irq(ipi_virq_base + i, 0);
}
void riscv_ipi_disable(void)
{
int i;
if (WARN_ON_ONCE(!ipi_virq_base))
return;
for (i = 0; i < nr_ipi; i++)
disable_percpu_irq(ipi_virq_base + i);
}
bool riscv_ipi_have_virq_range(void)
{
return (ipi_virq_base) ? true : false;
}
void riscv_ipi_set_virq_range(int virq, int nr)
{
int i, err;
if (WARN_ON(ipi_virq_base))
return;
WARN_ON(nr < IPI_MAX);
nr_ipi = min(nr, IPI_MAX);
ipi_virq_base = virq;
/* Request IPIs */
for (i = 0; i < nr_ipi; i++) {
err = request_percpu_irq(ipi_virq_base + i, handle_IPI,
"IPI", &ipi_dummy_dev);
WARN_ON(err);
ipi_desc[i] = irq_to_desc(ipi_virq_base + i);
irq_set_status_flags(ipi_virq_base + i, IRQ_HIDDEN);
}
/* Enabled IPIs for boot CPU immediately */
riscv_ipi_enable();
}
static const char * const ipi_names[] = {
@ -221,7 +219,7 @@ void show_ipi_stats(struct seq_file *p, int prec)
seq_printf(p, "%*s%u:%s", prec - 1, "IPI", i,
prec >= 4 ? " " : "");
for_each_online_cpu(cpu)
seq_printf(p, "%10lu ", ipi_data[cpu].stats[i]);
seq_printf(p, "%10u ", irq_desc_kstat_cpu(ipi_desc[i], cpu));
seq_printf(p, " %s\n", ipi_names[i]);
}
}

5
arch/riscv/kernel/smpboot.c
View File

@ -30,7 +30,6 @@
#include <asm/numa.h>
#include <asm/tlbflush.h>
#include <asm/sections.h>
#include <asm/sbi.h>
#include <asm/smp.h>
#include "head.h"
@ -158,12 +157,12 @@ asmlinkage __visible void smp_callin(void)
struct mm_struct *mm = &init_mm;
unsigned int curr_cpuid = smp_processor_id();
riscv_clear_ipi();
/* All kernel threads share the same mm context. */
mmgrab(mm);
current->active_mm = mm;
riscv_ipi_enable();
store_cpu_topology(curr_cpuid);
notify_cpu_starting(curr_cpuid);
numa_add_cpu(curr_cpuid);

65
drivers/clocksource/timer-clint.c
View File

@ -17,6 +17,9 @@
#include <linux/sched_clock.h>
#include <linux/io-64-nonatomic-lo-hi.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/irqchip/chained_irq.h>
#include <linux/irqdomain.h>
#include <linux/of_irq.h>
#include <linux/smp.h>
#include <linux/timex.h>
@ -31,6 +34,7 @@
/* CLINT manages IPI and Timer for RISC-V M-mode */
static u32 __iomem *clint_ipi_base;
static unsigned int clint_ipi_irq;
static u64 __iomem *clint_timer_cmp;
static u64 __iomem *clint_timer_val;
static unsigned long clint_timer_freq;
@ -41,12 +45,10 @@ u64 __iomem *clint_time_val;
EXPORT_SYMBOL(clint_time_val);
#endif
static void clint_send_ipi(const struct cpumask *target)
#ifdef CONFIG_SMP
static void clint_send_ipi(unsigned int cpu)
{
unsigned int cpu;
for_each_cpu(cpu, target)
writel(1, clint_ipi_base + cpuid_to_hartid_map(cpu));
writel(1, clint_ipi_base + cpuid_to_hartid_map(cpu));
}
static void clint_clear_ipi(void)
@ -54,10 +56,18 @@ static void clint_clear_ipi(void)
writel(0, clint_ipi_base + cpuid_to_hartid_map(smp_processor_id()));
}
static struct riscv_ipi_ops clint_ipi_ops = {
.ipi_inject = clint_send_ipi,
.ipi_clear = clint_clear_ipi,
};
static void clint_ipi_interrupt(struct irq_desc *desc)
{
struct irq_chip *chip = irq_desc_get_chip(desc);
chained_irq_enter(chip, desc);
clint_clear_ipi();
ipi_mux_process();
chained_irq_exit(chip, desc);
}
#endif
#ifdef CONFIG_64BIT
#define clint_get_cycles() readq_relaxed(clint_timer_val)
@ -125,12 +135,19 @@ static int clint_timer_starting_cpu(unsigned int cpu)
enable_percpu_irq(clint_timer_irq,
irq_get_trigger_type(clint_timer_irq));
enable_percpu_irq(clint_ipi_irq,
irq_get_trigger_type(clint_ipi_irq));
return 0;
}
static int clint_timer_dying_cpu(unsigned int cpu)
{
disable_percpu_irq(clint_timer_irq);
/*
* Don't disable IPI when CPU goes offline because
* the masking/unmasking of virtual IPIs is done
* via generic IPI-Mux
*/
return 0;
}
@ -170,6 +187,12 @@ static int __init clint_timer_init_dt(struct device_node *np)
return -ENODEV;
}
/* Find parent irq domain and map ipi irq */
if (!clint_ipi_irq &&
oirq.args[0] == RV_IRQ_SOFT &&
irq_find_host(oirq.np))
clint_ipi_irq = irq_of_parse_and_map(np, i);
/* Find parent irq domain and map timer irq */
if (!clint_timer_irq &&
oirq.args[0] == RV_IRQ_TIMER &&
@ -177,9 +200,9 @@ static int __init clint_timer_init_dt(struct device_node *np)
clint_timer_irq = irq_of_parse_and_map(np, i);
}
/* If CLINT timer irq not found then fail */
if (!clint_timer_irq) {
pr_err("%pOFP: timer irq not found\n", np);
/* If CLINT ipi or timer irq not found then fail */
if (!clint_ipi_irq || !clint_timer_irq) {
pr_err("%pOFP: ipi/timer irq not found\n", np);
return -ENODEV;
}
@ -219,6 +242,19 @@ static int __init clint_timer_init_dt(struct device_node *np)
goto fail_iounmap;
}
#ifdef CONFIG_SMP
rc = ipi_mux_create(BITS_PER_BYTE, clint_send_ipi);
if (rc <= 0) {
pr_err("unable to create muxed IPIs\n");
rc = (rc < 0) ? rc : -ENODEV;
goto fail_free_irq;
}
irq_set_chained_handler(clint_ipi_irq, clint_ipi_interrupt);
riscv_ipi_set_virq_range(rc, BITS_PER_BYTE);
clint_clear_ipi();
#endif
rc = cpuhp_setup_state(CPUHP_AP_CLINT_TIMER_STARTING,
"clockevents/clint/timer:starting",
clint_timer_starting_cpu,
@ -228,13 +264,10 @@ static int __init clint_timer_init_dt(struct device_node *np)
goto fail_free_irq;
}
riscv_set_ipi_ops(&clint_ipi_ops);
clint_clear_ipi();
return 0;
fail_free_irq:
free_irq(clint_timer_irq, &clint_clock_event);
free_percpu_irq(clint_timer_irq, &clint_clock_event);
fail_iounmap:
iounmap(base);
return rc;

1
drivers/irqchip/Kconfig
View File

@ -535,6 +535,7 @@ config TI_PRUSS_INTC
config RISCV_INTC
bool
depends on RISCV
select IRQ_DOMAIN_HIERARCHY
config SIFIVE_PLIC
bool

55
drivers/irqchip/irq-riscv-intc.c
View File

@ -26,20 +26,7 @@ static asmlinkage void riscv_intc_irq(struct pt_regs *regs)
if (unlikely(cause >= BITS_PER_LONG))
panic("unexpected interrupt cause");
switch (cause) {
#ifdef CONFIG_SMP
case RV_IRQ_SOFT:
/*
* We only use software interrupts to pass IPIs, so if a
* non-SMP system gets one, then we don't know what to do.
*/
handle_IPI(regs);
break;
#endif
default:
generic_handle_domain_irq(intc_domain, cause);
break;
}
generic_handle_domain_irq(intc_domain, cause);
}
/*
@ -59,18 +46,6 @@ static void riscv_intc_irq_unmask(struct irq_data *d)
csr_set(CSR_IE, BIT(d->hwirq));
}
static int riscv_intc_cpu_starting(unsigned int cpu)
{
csr_set(CSR_IE, BIT(RV_IRQ_SOFT));
return 0;
}
static int riscv_intc_cpu_dying(unsigned int cpu)
{
csr_clear(CSR_IE, BIT(RV_IRQ_SOFT));
return 0;
}
static struct irq_chip riscv_intc_chip = {
.name = "RISC-V INTC",
.irq_mask = riscv_intc_irq_mask,
@ -87,9 +62,32 @@ static int riscv_intc_domain_map(struct irq_domain *d, unsigned int irq,
return 0;
}
static int riscv_intc_domain_alloc(struct irq_domain *domain,
unsigned int virq, unsigned int nr_irqs,
void *arg)
{
int i, ret;
irq_hw_number_t hwirq;
unsigned int type = IRQ_TYPE_NONE;
struct irq_fwspec *fwspec = arg;
ret = irq_domain_translate_onecell(domain, fwspec, &hwirq, &type);
if (ret)
return ret;
for (i = 0; i < nr_irqs; i++) {
ret = riscv_intc_domain_map(domain, virq + i, hwirq + i);
if (ret)
return ret;
}
return 0;
}
static const struct irq_domain_ops riscv_intc_domain_ops = {
.map = riscv_intc_domain_map,
.xlate = irq_domain_xlate_onecell,
.alloc = riscv_intc_domain_alloc
};
static struct fwnode_handle *riscv_intc_hwnode(void)
@ -133,11 +131,6 @@ static int __init riscv_intc_init(struct device_node *node,
riscv_set_intc_hwnode_fn(riscv_intc_hwnode);
cpuhp_setup_state(CPUHP_AP_IRQ_RISCV_STARTING,
"irqchip/riscv/intc:starting",
riscv_intc_cpu_starting,
riscv_intc_cpu_dying);
pr_info("%d local interrupts mapped\n", BITS_PER_LONG);
return 0;