LoongArch-based procesors have 4, 8 or 16 cores per package. This patch adds multi-processor (SMP) support for LoongArch. Reviewed-by: WANG Xuerui <git@xxxxxxxxxx> Reviewed-by: Jiaxun Yang <jiaxun.yang@xxxxxxxxxxx> Signed-off-by: Huacai Chen <chenhuacai@xxxxxxxxxxx> --- arch/loongarch/Kconfig | 40 +- arch/loongarch/include/asm/atomic.h | 4 + arch/loongarch/include/asm/barrier.h | 108 ++++ arch/loongarch/include/asm/cmpxchg.h | 1 + arch/loongarch/include/asm/futex.h | 1 + arch/loongarch/include/asm/hardirq.h | 2 + arch/loongarch/include/asm/irq.h | 2 + arch/loongarch/include/asm/percpu.h | 194 +++++++ arch/loongarch/include/asm/pgtable.h | 21 + arch/loongarch/include/asm/smp.h | 124 ++++ arch/loongarch/include/asm/stackframe.h | 17 +- arch/loongarch/include/asm/tlbflush.h | 13 + arch/loongarch/include/asm/topology.h | 7 +- arch/loongarch/kernel/Makefile | 2 + arch/loongarch/kernel/acpi.c | 69 +++ arch/loongarch/kernel/asm-offsets.c | 10 + arch/loongarch/kernel/head.S | 30 + arch/loongarch/kernel/irq.c | 13 +- arch/loongarch/kernel/proc.c | 5 + arch/loongarch/kernel/process.c | 7 + arch/loongarch/kernel/reset.c | 12 + arch/loongarch/kernel/setup.c | 26 + arch/loongarch/kernel/smp.c | 735 ++++++++++++++++++++++++ arch/loongarch/kernel/topology.c | 43 +- arch/loongarch/kernel/vmlinux.lds.S | 4 + arch/loongarch/mm/tlbex.S | 69 +++ include/linux/cpuhotplug.h | 1 + 27 files changed, 1550 insertions(+), 10 deletions(-) create mode 100644 arch/loongarch/include/asm/smp.h create mode 100644 arch/loongarch/kernel/smp.c diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig index 03d9b74eb2a9..85ef258d36d2 100644 --- a/arch/loongarch/Kconfig +++ b/arch/loongarch/Kconfig @@ -64,6 +64,7 @@ config LOONGARCH select GENERIC_LIB_UCMPDI2 select GENERIC_PCI_IOMAP select GENERIC_SCHED_CLOCK + select GENERIC_SMP_IDLE_THREAD select GENERIC_TIME_VSYSCALL select GPIOLIB select HAVE_ARCH_AUDITSYSCALL @@ -92,7 +93,7 @@ config LOONGARCH select HAVE_RSEQ select HAVE_SYSCALL_TRACEPOINTS select HAVE_TIF_NOHZ - select HAVE_VIRT_CPU_ACCOUNTING_GEN + select HAVE_VIRT_CPU_ACCOUNTING_GEN if !SMP select IRQ_FORCED_THREADING select IRQ_LOONGARCH_CPU select MODULES_USE_ELF_RELA if MODULES @@ -297,6 +298,43 @@ config EFI This enables the kernel to use EFI runtime services that are available (such as the EFI variable services). +config SMP + bool "Multi-Processing support" + 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. + + If you say N here, the kernel will run on uni- and multiprocessor + machines, but will use only one CPU of a multiprocessor machine. If + you say Y here, the kernel will run on many, but not all, + uniprocessor machines. On a uniprocessor machine, the kernel + will run faster if you say N here. + + See also the SMP-HOWTO available at <http://www.tldp.org/docs.html#howto>. + + If you don't know what to do here, say N. + +config HOTPLUG_CPU + bool "Support for hot-pluggable CPUs" + depends on SMP + select GENERIC_IRQ_MIGRATION + help + Say Y here to allow turning CPUs off and on. CPUs can be + controlled through /sys/devices/system/cpu. + (Note: power management support will enable this option + automatically on SMP systems. ) + Say N if you want to disable CPU hotplug. + +config NR_CPUS + int "Maximum number of CPUs (2-256)" + range 2 256 + depends on SMP + default "64" + help + This allows you to specify the maximum number of CPUs which this + kernel will support. + config FORCE_MAX_ZONEORDER int "Maximum zone order" range 14 64 if PAGE_SIZE_64KB diff --git a/arch/loongarch/include/asm/atomic.h b/arch/loongarch/include/asm/atomic.h index 932352342b12..979367ad4e2c 100644 --- a/arch/loongarch/include/asm/atomic.h +++ b/arch/loongarch/include/asm/atomic.h @@ -162,6 +162,7 @@ static inline int arch_atomic_sub_if_positive(int i, atomic_t *v) " sc.w %1, %2 \n" " beq $zero, %1, 1b \n" "2: \n" + __WEAK_LLSC_MB : "=&r" (result), "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (v->counter) : "I" (-i)); @@ -174,6 +175,7 @@ static inline int arch_atomic_sub_if_positive(int i, atomic_t *v) " sc.w %1, %2 \n" " beq $zero, %1, 1b \n" "2: \n" + __WEAK_LLSC_MB : "=&r" (result), "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (v->counter) : "r" (i)); @@ -323,6 +325,7 @@ static inline long arch_atomic64_sub_if_positive(long i, atomic64_t *v) " sc.d %1, %2 \n" " beq %1, $zero, 1b \n" "2: \n" + __WEAK_LLSC_MB : "=&r" (result), "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (v->counter) : "I" (-i)); @@ -335,6 +338,7 @@ static inline long arch_atomic64_sub_if_positive(long i, atomic64_t *v) " sc.d %1, %2 \n" " beq %1, $zero, 1b \n" "2: \n" + __WEAK_LLSC_MB : "=&r" (result), "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (v->counter) : "r" (i)); diff --git a/arch/loongarch/include/asm/barrier.h b/arch/loongarch/include/asm/barrier.h index e57571bcaf4f..b6517eeeb141 100644 --- a/arch/loongarch/include/asm/barrier.h +++ b/arch/loongarch/include/asm/barrier.h @@ -18,6 +18,19 @@ #define mb() fast_mb() #define iob() fast_iob() +#define __smp_mb() __asm__ __volatile__("dbar 0" : : : "memory") +#define __smp_rmb() __asm__ __volatile__("dbar 0" : : : "memory") +#define __smp_wmb() __asm__ __volatile__("dbar 0" : : : "memory") + +#ifdef CONFIG_SMP +#define __WEAK_LLSC_MB " dbar 0 \n" +#else +#define __WEAK_LLSC_MB " \n" +#endif + +#define __smp_mb__before_atomic() barrier() +#define __smp_mb__after_atomic() barrier() + /** * array_index_mask_nospec() - generate a ~0 mask when index < size, 0 otherwise * @index: array element index @@ -46,6 +59,101 @@ static inline unsigned long array_index_mask_nospec(unsigned long index, return mask; } +#define __smp_load_acquire(p) \ +({ \ + union { typeof(*p) __val; char __c[1]; } __u; \ + unsigned long __tmp = 0; \ + compiletime_assert_atomic_type(*p); \ + switch (sizeof(*p)) { \ + case 1: \ + *(__u8 *)__u.__c = *(volatile __u8 *)p; \ + __smp_mb(); \ + break; \ + case 2: \ + *(__u16 *)__u.__c = *(volatile __u16 *)p; \ + __smp_mb(); \ + break; \ + case 4: \ + __asm__ __volatile__( \ + "amor_db.w %[val], %[tmp], %[mem] \n" \ + : [val] "=&r" (*(__u32 *)__u.__c) \ + : [mem] "ZB" (*(u32 *) p), [tmp] "r" (__tmp) \ + : "memory"); \ + break; \ + case 8: \ + __asm__ __volatile__( \ + "amor_db.d %[val], %[tmp], %[mem] \n" \ + : [val] "=&r" (*(__u64 *)__u.__c) \ + : [mem] "ZB" (*(u64 *) p), [tmp] "r" (__tmp) \ + : "memory"); \ + break; \ + } \ + (typeof(*p))__u.__val; \ +}) + +#define __smp_store_release(p, v) \ +do { \ + union { typeof(*p) __val; char __c[1]; } __u = \ + { .__val = (__force typeof(*p)) (v) }; \ + unsigned long __tmp; \ + compiletime_assert_atomic_type(*p); \ + switch (sizeof(*p)) { \ + case 1: \ + __smp_mb(); \ + *(volatile __u8 *)p = *(__u8 *)__u.__c; \ + break; \ + case 2: \ + __smp_mb(); \ + *(volatile __u16 *)p = *(__u16 *)__u.__c; \ + break; \ + case 4: \ + __asm__ __volatile__( \ + "amswap_db.w %[tmp], %[val], %[mem] \n" \ + : [mem] "+ZB" (*(u32 *)p), [tmp] "=&r" (__tmp) \ + : [val] "r" (*(__u32 *)__u.__c) \ + : ); \ + break; \ + case 8: \ + __asm__ __volatile__( \ + "amswap_db.d %[tmp], %[val], %[mem] \n" \ + : [mem] "+ZB" (*(u64 *)p), [tmp] "=&r" (__tmp) \ + : [val] "r" (*(__u64 *)__u.__c) \ + : ); \ + break; \ + } \ +} while (0) + +#define __smp_store_mb(p, v) \ +do { \ + union { typeof(p) __val; char __c[1]; } __u = \ + { .__val = (__force typeof(p)) (v) }; \ + unsigned long __tmp; \ + switch (sizeof(p)) { \ + case 1: \ + *(volatile __u8 *)&p = *(__u8 *)__u.__c; \ + __smp_mb(); \ + break; \ + case 2: \ + *(volatile __u16 *)&p = *(__u16 *)__u.__c; \ + __smp_mb(); \ + break; \ + case 4: \ + __asm__ __volatile__( \ + "amswap_db.w %[tmp], %[val], %[mem] \n" \ + : [mem] "+ZB" (*(u32 *)&p), [tmp] "=&r" (__tmp) \ + : [val] "r" (*(__u32 *)__u.__c) \ + : ); \ + break; \ + case 8: \ + __asm__ __volatile__( \ + "amswap_db.d %[tmp], %[val], %[mem] \n" \ + : [mem] "+ZB" (*(u64 *)&p), [tmp] "=&r" (__tmp) \ + : [val] "r" (*(__u64 *)__u.__c) \ + : ); \ + break; \ + } \ +} while (0) + #include <asm-generic/barrier.h> #endif /* __ASM_BARRIER_H */ diff --git a/arch/loongarch/include/asm/cmpxchg.h b/arch/loongarch/include/asm/cmpxchg.h index 48613b872bc8..75b3a4478652 100644 --- a/arch/loongarch/include/asm/cmpxchg.h +++ b/arch/loongarch/include/asm/cmpxchg.h @@ -59,6 +59,7 @@ static inline unsigned long __xchg(volatile void *ptr, unsigned long x, " " st " $t0, %1 \n" \ " beq $zero, $t0, 1b \n" \ "2: \n" \ + __WEAK_LLSC_MB \ : "=&r" (__ret), "=ZB"(*m) \ : "ZB"(*m), "Jr" (old), "Jr" (new) \ : "t0", "memory"); \ diff --git a/arch/loongarch/include/asm/futex.h b/arch/loongarch/include/asm/futex.h index b27d55f92db7..9de8231694ec 100644 --- a/arch/loongarch/include/asm/futex.h +++ b/arch/loongarch/include/asm/futex.h @@ -86,6 +86,7 @@ futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr, u32 oldval, u32 newv "2: sc.w $t0, %2 \n" " beq $zero, $t0, 1b \n" "3: \n" + __WEAK_LLSC_MB " .section .fixup,\"ax\" \n" "4: li.d %0, %6 \n" " b 3b \n" diff --git a/arch/loongarch/include/asm/hardirq.h b/arch/loongarch/include/asm/hardirq.h index d32f83938880..befe8184aa08 100644 --- a/arch/loongarch/include/asm/hardirq.h +++ b/arch/loongarch/include/asm/hardirq.h @@ -21,4 +21,6 @@ typedef struct { DECLARE_PER_CPU_ALIGNED(irq_cpustat_t, irq_stat); +#define __ARCH_IRQ_STAT + #endif /* _ASM_HARDIRQ_H */ diff --git a/arch/loongarch/include/asm/irq.h b/arch/loongarch/include/asm/irq.h index f3f1baf7027c..ace3ea6da72e 100644 --- a/arch/loongarch/include/asm/irq.h +++ b/arch/loongarch/include/asm/irq.h @@ -125,6 +125,8 @@ extern struct irq_domain *pch_lpc_domain; extern struct irq_domain *pch_msi_domain[MAX_IO_PICS]; extern struct irq_domain *pch_pic_domain[MAX_IO_PICS]; +extern irqreturn_t loongson3_ipi_interrupt(int irq, void *dev); + #include <asm-generic/irq.h> #endif /* _ASM_IRQ_H */ diff --git a/arch/loongarch/include/asm/percpu.h b/arch/loongarch/include/asm/percpu.h index b03d8f8b9fd3..34f15a6fb1e7 100644 --- a/arch/loongarch/include/asm/percpu.h +++ b/arch/loongarch/include/asm/percpu.h @@ -5,6 +5,8 @@ #ifndef __ASM_PERCPU_H #define __ASM_PERCPU_H +#include <asm/cmpxchg.h> + /* Use r21 for fast access */ register unsigned long __my_cpu_offset __asm__("$r21"); @@ -15,6 +17,198 @@ static inline void set_my_cpu_offset(unsigned long off) } #define __my_cpu_offset __my_cpu_offset +#define PERCPU_OP(op, asm_op, c_op) \ +static inline unsigned long __percpu_##op(void *ptr, \ + unsigned long val, int size) \ +{ \ + unsigned long ret; \ + \ + switch (size) { \ + case 4: \ + __asm__ __volatile__( \ + "am"#asm_op".w" " %[ret], %[val], %[ptr] \n" \ + : [ret] "=&r" (ret), [ptr] "+ZB"(*(u32 *)ptr) \ + : [val] "r" (val)); \ + break; \ + case 8: \ + __asm__ __volatile__( \ + "am"#asm_op".d" " %[ret], %[val], %[ptr] \n" \ + : [ret] "=&r" (ret), [ptr] "+ZB"(*(u64 *)ptr) \ + : [val] "r" (val)); \ + break; \ + default: \ + ret = 0; \ + BUILD_BUG(); \ + } \ + \ + return ret c_op val; \ +} + +PERCPU_OP(add, add, +) +PERCPU_OP(and, and, &) +PERCPU_OP(or, or, |) +#undef PERCPU_OP + +static inline unsigned long __percpu_read(void *ptr, int size) +{ + unsigned long ret; + + switch (size) { + case 1: + __asm__ __volatile__ ("ldx.b %[ret], $r21, %[ptr] \n" + : [ret] "=&r"(ret) + : [ptr] "r"(ptr) + : "memory"); + break; + case 2: + __asm__ __volatile__ ("ldx.h %[ret], $r21, %[ptr] \n" + : [ret] "=&r"(ret) + : [ptr] "r"(ptr) + : "memory"); + break; + case 4: + __asm__ __volatile__ ("ldx.w %[ret], $r21, %[ptr] \n" + : [ret] "=&r"(ret) + : [ptr] "r"(ptr) + : "memory"); + break; + case 8: + __asm__ __volatile__ ("ldx.d %[ret], $r21, %[ptr] \n" + : [ret] "=&r"(ret) + : [ptr] "r"(ptr) + : "memory"); + break; + default: + ret = 0; + BUILD_BUG(); + } + + return ret; +} + +static inline void __percpu_write(void *ptr, unsigned long val, int size) +{ + switch (size) { + case 1: + __asm__ __volatile__("stx.b %[val], $r21, %[ptr] \n" + : + : [val] "r" (val), [ptr] "r" (ptr) + : "memory"); + break; + case 2: + __asm__ __volatile__("stx.h %[val], $r21, %[ptr] \n" + : + : [val] "r" (val), [ptr] "r" (ptr) + : "memory"); + break; + case 4: + __asm__ __volatile__("stx.w %[val], $r21, %[ptr] \n" + : + : [val] "r" (val), [ptr] "r" (ptr) + : "memory"); + break; + case 8: + __asm__ __volatile__("stx.d %[val], $r21, %[ptr] \n" + : + : [val] "r" (val), [ptr] "r" (ptr) + : "memory"); + break; + default: + BUILD_BUG(); + } +} + +static inline unsigned long __percpu_xchg(void *ptr, unsigned long val, + int size) +{ + switch (size) { + case 4: + return __xchg_asm("amswap.w", (volatile u32 *)ptr, (u32)val); + + case 8: + return __xchg_asm("amswap.d", (volatile u64 *)ptr, (u64)val); + + default: + BUILD_BUG(); + } + + return 0; +} + +/* this_cpu_cmpxchg */ +#define _protect_cmpxchg_local(pcp, o, n) \ +({ \ + typeof(*raw_cpu_ptr(&(pcp))) __ret; \ + preempt_disable_notrace(); \ + __ret = cmpxchg_local(raw_cpu_ptr(&(pcp)), o, n); \ + preempt_enable_notrace(); \ + __ret; \ +}) + +#define _percpu_read(pcp) \ +({ \ + typeof(pcp) __retval; \ + __retval = (typeof(pcp))__percpu_read(&(pcp), sizeof(pcp)); \ + __retval; \ +}) + +#define _percpu_write(pcp, val) \ +do { \ + __percpu_write(&(pcp), (unsigned long)(val), sizeof(pcp)); \ +} while (0) \ + +#define _pcp_protect(operation, pcp, val) \ +({ \ + typeof(pcp) __retval; \ + preempt_disable_notrace(); \ + __retval = (typeof(pcp))operation(raw_cpu_ptr(&(pcp)), \ + (val), sizeof(pcp)); \ + preempt_enable_notrace(); \ + __retval; \ +}) + +#define _percpu_add(pcp, val) \ + _pcp_protect(__percpu_add, pcp, val) + +#define _percpu_add_return(pcp, val) _percpu_add(pcp, val) + +#define _percpu_and(pcp, val) \ + _pcp_protect(__percpu_and, pcp, val) + +#define _percpu_or(pcp, val) \ + _pcp_protect(__percpu_or, pcp, val) + +#define _percpu_xchg(pcp, val) ((typeof(pcp)) \ + _pcp_protect(__percpu_xchg, pcp, (unsigned long)(val))) + +#define this_cpu_add_4(pcp, val) _percpu_add(pcp, val) +#define this_cpu_add_8(pcp, val) _percpu_add(pcp, val) + +#define this_cpu_add_return_4(pcp, val) _percpu_add_return(pcp, val) +#define this_cpu_add_return_8(pcp, val) _percpu_add_return(pcp, val) + +#define this_cpu_and_4(pcp, val) _percpu_and(pcp, val) +#define this_cpu_and_8(pcp, val) _percpu_and(pcp, val) + +#define this_cpu_or_4(pcp, val) _percpu_or(pcp, val) +#define this_cpu_or_8(pcp, val) _percpu_or(pcp, val) + +#define this_cpu_read_1(pcp) _percpu_read(pcp) +#define this_cpu_read_2(pcp) _percpu_read(pcp) +#define this_cpu_read_4(pcp) _percpu_read(pcp) +#define this_cpu_read_8(pcp) _percpu_read(pcp) + +#define this_cpu_write_1(pcp, val) _percpu_write(pcp, val) +#define this_cpu_write_2(pcp, val) _percpu_write(pcp, val) +#define this_cpu_write_4(pcp, val) _percpu_write(pcp, val) +#define this_cpu_write_8(pcp, val) _percpu_write(pcp, val) + +#define this_cpu_xchg_4(pcp, val) _percpu_xchg(pcp, val) +#define this_cpu_xchg_8(pcp, val) _percpu_xchg(pcp, val) + +#define this_cpu_cmpxchg_4(ptr, o, n) _protect_cmpxchg_local(ptr, o, n) +#define this_cpu_cmpxchg_8(ptr, o, n) _protect_cmpxchg_local(ptr, o, n) + #include <asm-generic/percpu.h> #endif /* __ASM_PERCPU_H */ diff --git a/arch/loongarch/include/asm/pgtable.h b/arch/loongarch/include/asm/pgtable.h index 8920dd8b297b..5e33987d0a13 100644 --- a/arch/loongarch/include/asm/pgtable.h +++ b/arch/loongarch/include/asm/pgtable.h @@ -279,8 +279,29 @@ static inline void set_pte(pte_t *ptep, pte_t pteval) * Make sure the buddy is global too (if it's !none, * it better already be global) */ +#ifdef CONFIG_SMP + /* + * For SMP, multiple CPUs can race, so we need to do + * this atomically. + */ + unsigned long page_global = _PAGE_GLOBAL; + unsigned long tmp; + + __asm__ __volatile__ ( + "1:" __LL "%[tmp], %[buddy] \n" + " bnez %[tmp], 2f \n" + " or %[tmp], %[tmp], %[global] \n" + __SC "%[tmp], %[buddy] \n" + " beqz %[tmp], 1b \n" + " nop \n" + "2: \n" + __WEAK_LLSC_MB + : [buddy] "+m" (buddy->pte), [tmp] "=&r" (tmp) + : [global] "r" (page_global)); +#else /* !CONFIG_SMP */ if (pte_none(*buddy)) pte_val(*buddy) = pte_val(*buddy) | _PAGE_GLOBAL; +#endif /* CONFIG_SMP */ } } diff --git a/arch/loongarch/include/asm/smp.h b/arch/loongarch/include/asm/smp.h new file mode 100644 index 000000000000..551e1f37c705 --- /dev/null +++ b/arch/loongarch/include/asm/smp.h @@ -0,0 +1,124 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Author: Huacai Chen <chenhuacai@xxxxxxxxxxx> + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited + */ +#ifndef __ASM_SMP_H +#define __ASM_SMP_H + +#include <linux/atomic.h> +#include <linux/bitops.h> +#include <linux/linkage.h> +#include <linux/smp.h> +#include <linux/threads.h> +#include <linux/cpumask.h> + +void loongson3_smp_setup(void); +void loongson3_prepare_cpus(unsigned int max_cpus); +void loongson3_boot_secondary(int cpu, struct task_struct *idle); +void loongson3_init_secondary(void); +void loongson3_smp_finish(void); +void loongson3_send_ipi_single(int cpu, unsigned int action); +void loongson3_send_ipi_mask(const struct cpumask *mask, unsigned int action); +#ifdef CONFIG_HOTPLUG_CPU +int loongson3_cpu_disable(void); +void loongson3_cpu_die(unsigned int cpu); +#endif + +#ifdef CONFIG_SMP + +static inline void plat_smp_setup(void) +{ + loongson3_smp_setup(); +} + +#else /* !CONFIG_SMP */ + +static inline void plat_smp_setup(void) { } + +#endif /* !CONFIG_SMP */ + +extern int smp_num_siblings; +extern int num_processors; +extern int disabled_cpus; +extern cpumask_t cpu_sibling_map[]; +extern cpumask_t cpu_core_map[]; +extern cpumask_t cpu_foreign_map[]; + +static inline int raw_smp_processor_id(void) +{ +#if defined(__VDSO__) + extern int vdso_smp_processor_id(void) + __compiletime_error("VDSO should not call smp_processor_id()"); + return vdso_smp_processor_id(); +#else + return current_thread_info()->cpu; +#endif +} +#define raw_smp_processor_id raw_smp_processor_id + +/* Map from cpu id to sequential logical cpu number. This will only + * not be idempotent when cpus failed to come on-line. */ +extern int __cpu_number_map[NR_CPUS]; +#define cpu_number_map(cpu) __cpu_number_map[cpu] + +/* The reverse map from sequential logical cpu number to cpu id. */ +extern int __cpu_logical_map[NR_CPUS]; +#define cpu_logical_map(cpu) __cpu_logical_map[cpu] + +#define cpu_physical_id(cpu) cpu_logical_map(cpu) + +#define SMP_BOOT_CPU 0x1 +#define SMP_RESCHEDULE 0x2 +#define SMP_CALL_FUNCTION 0x4 + +struct secondary_data { + unsigned long stack; + unsigned long thread_info; +}; +extern struct secondary_data cpuboot_data; + +extern asmlinkage void smpboot_entry(void); + +extern void calculate_cpu_foreign_map(void); + +/* + * Generate IPI list text + */ +extern void show_ipi_list(struct seq_file *p, int prec); + +/* + * This function sends a 'reschedule' IPI to another CPU. + * it goes straight through and wastes no time serializing + * anything. Worst case is that we lose a reschedule ... + */ +static inline void smp_send_reschedule(int cpu) +{ + loongson3_send_ipi_single(cpu, SMP_RESCHEDULE); +} + +static inline void arch_send_call_function_single_ipi(int cpu) +{ + loongson3_send_ipi_single(cpu, SMP_CALL_FUNCTION); +} + +static inline void arch_send_call_function_ipi_mask(const struct cpumask *mask) +{ + loongson3_send_ipi_mask(mask, SMP_CALL_FUNCTION); +} + +#ifdef CONFIG_HOTPLUG_CPU +static inline int __cpu_disable(void) +{ + return loongson3_cpu_disable(); +} + +static inline void __cpu_die(unsigned int cpu) +{ + loongson3_cpu_die(cpu); +} + +extern void play_dead(void); +#endif + +#endif /* __ASM_SMP_H */ diff --git a/arch/loongarch/include/asm/stackframe.h b/arch/loongarch/include/asm/stackframe.h index 44151b878d00..4ca953062b5b 100644 --- a/arch/loongarch/include/asm/stackframe.h +++ b/arch/loongarch/include/asm/stackframe.h @@ -77,17 +77,24 @@ * new value in sp. */ .macro get_saved_sp docfi=0 - la.abs t1, kernelsp - move t0, sp + la.abs t1, kernelsp +#ifdef CONFIG_SMP + csrrd t0, PERCPU_BASE_KS + LONG_ADD t1, t1, t0 +#endif + move t0, sp .if \docfi .cfi_register sp, t0 .endif - LONG_L sp, t1, 0 + LONG_L sp, t1, 0 .endm .macro set_saved_sp stackp temp temp2 - la.abs \temp, kernelsp - LONG_S \stackp, \temp, 0 + la.abs \temp, kernelsp +#ifdef CONFIG_SMP + LONG_ADD \temp, \temp, u0 +#endif + LONG_S \stackp, \temp, 0 .endm .macro SAVE_SOME docfi=0 diff --git a/arch/loongarch/include/asm/tlbflush.h b/arch/loongarch/include/asm/tlbflush.h index 36bd6d11dc2d..a0785e590681 100644 --- a/arch/loongarch/include/asm/tlbflush.h +++ b/arch/loongarch/include/asm/tlbflush.h @@ -25,6 +25,17 @@ extern void local_flush_tlb_kernel_range(unsigned long start, unsigned long end) extern void local_flush_tlb_page(struct vm_area_struct *vma, unsigned long page); extern void local_flush_tlb_one(unsigned long vaddr); +#ifdef CONFIG_SMP + +extern void flush_tlb_all(void); +extern void flush_tlb_mm(struct mm_struct *); +extern void flush_tlb_range(struct vm_area_struct *vma, unsigned long, unsigned long); +extern void flush_tlb_kernel_range(unsigned long, unsigned long); +extern void flush_tlb_page(struct vm_area_struct *, unsigned long); +extern void flush_tlb_one(unsigned long vaddr); + +#else /* CONFIG_SMP */ + #define flush_tlb_all() local_flush_tlb_all() #define flush_tlb_mm(mm) local_flush_tlb_mm(mm) #define flush_tlb_range(vma, vmaddr, end) local_flush_tlb_range(vma, vmaddr, end) @@ -32,4 +43,6 @@ extern void local_flush_tlb_one(unsigned long vaddr); #define flush_tlb_page(vma, page) local_flush_tlb_page(vma, page) #define flush_tlb_one(vaddr) local_flush_tlb_one(vaddr) +#endif /* CONFIG_SMP */ + #endif /* __ASM_TLBFLUSH_H */ diff --git a/arch/loongarch/include/asm/topology.h b/arch/loongarch/include/asm/topology.h index 9ac71a25207a..da135841e5b1 100644 --- a/arch/loongarch/include/asm/topology.h +++ b/arch/loongarch/include/asm/topology.h @@ -7,7 +7,12 @@ #include <linux/smp.h> -#define cpu_logical_map(cpu) 0 +#ifdef CONFIG_SMP +#define topology_physical_package_id(cpu) (cpu_data[cpu].package) +#define topology_core_id(cpu) (cpu_data[cpu].core) +#define topology_core_cpumask(cpu) (&cpu_core_map[cpu]) +#define topology_sibling_cpumask(cpu) (&cpu_sibling_map[cpu]) +#endif #include <asm-generic/topology.h> diff --git a/arch/loongarch/kernel/Makefile b/arch/loongarch/kernel/Makefile index e5a3b2fb9961..2cb6f698716a 100644 --- a/arch/loongarch/kernel/Makefile +++ b/arch/loongarch/kernel/Makefile @@ -18,4 +18,6 @@ obj-$(CONFIG_MODULES) += module.o module-sections.o obj-$(CONFIG_PROC_FS) += proc.o +obj-$(CONFIG_SMP) += smp.o + CPPFLAGS_vmlinux.lds := $(KBUILD_CFLAGS) diff --git a/arch/loongarch/kernel/acpi.c b/arch/loongarch/kernel/acpi.c index a644220bb426..181c59493b63 100644 --- a/arch/loongarch/kernel/acpi.c +++ b/arch/loongarch/kernel/acpi.c @@ -137,8 +137,44 @@ void __init acpi_boot_table_init(void) } } +static int set_processor_mask(u32 id, u32 flags) +{ + + int cpu, cpuid = id; + + if (num_processors >= nr_cpu_ids) { + pr_warn(PREFIX "nr_cpus/possible_cpus limit of %i reached." + " processor 0x%x ignored.\n", nr_cpu_ids, cpuid); + + return -ENODEV; + + } + if (cpuid == loongson_sysconf.boot_cpu_id) + cpu = 0; + else + cpu = cpumask_next_zero(-1, cpu_present_mask); + + if (flags & ACPI_MADT_ENABLED) { + num_processors++; + set_cpu_possible(cpu, true); + set_cpu_present(cpu, true); + __cpu_number_map[cpuid] = cpu; + __cpu_logical_map[cpu] = cpuid; + } else + disabled_cpus++; + + return cpu; +} + static void __init acpi_process_madt(void) { + int i; + + for (i = 0; i < NR_CPUS; i++) { + __cpu_number_map[i] = -1; + __cpu_logical_map[i] = -1; + } + loongson_sysconf.nr_cpus = num_processors; } @@ -167,3 +203,36 @@ void __init arch_reserve_mem_area(acpi_physical_address addr, size_t size) { memblock_reserve(addr, size); } + +#ifdef CONFIG_ACPI_HOTPLUG_CPU + +#include <acpi/processor.h> + +int acpi_map_cpu(acpi_handle handle, phys_cpuid_t physid, u32 acpi_id, int *pcpu) +{ + int cpu; + + cpu = set_processor_mask(physid, ACPI_MADT_ENABLED); + if (cpu < 0) { + pr_info(PREFIX "Unable to map lapic to logical cpu number\n"); + return cpu; + } + + *pcpu = cpu; + + return 0; +} +EXPORT_SYMBOL(acpi_map_cpu); + +int acpi_unmap_cpu(int cpu) +{ + set_cpu_present(cpu, false); + num_processors--; + + pr_info("cpu%d hot remove!\n", cpu); + + return 0; +} +EXPORT_SYMBOL(acpi_unmap_cpu); + +#endif /* CONFIG_ACPI_HOTPLUG_CPU */ diff --git a/arch/loongarch/kernel/asm-offsets.c b/arch/loongarch/kernel/asm-offsets.c index 3531e3c60a6e..bfb65eb2844f 100644 --- a/arch/loongarch/kernel/asm-offsets.c +++ b/arch/loongarch/kernel/asm-offsets.c @@ -252,3 +252,13 @@ void output_signal_defines(void) DEFINE(_SIGXFSZ, SIGXFSZ); BLANK(); } + +#ifdef CONFIG_SMP +void output_smpboot_defines(void) +{ + COMMENT("Linux smp cpu boot offsets."); + OFFSET(CPU_BOOT_STACK, secondary_data, stack); + OFFSET(CPU_BOOT_TINFO, secondary_data, thread_info); + BLANK(); +} +#endif diff --git a/arch/loongarch/kernel/head.S b/arch/loongarch/kernel/head.S index 57dabb699bb7..e596dfcd924b 100644 --- a/arch/loongarch/kernel/head.S +++ b/arch/loongarch/kernel/head.S @@ -65,4 +65,34 @@ SYM_CODE_START(kernel_entry) # kernel entry point SYM_CODE_END(kernel_entry) +#ifdef CONFIG_SMP + +/* + * SMP slave cpus entry point. Board specific code for bootstrap calls this + * function after setting up the stack and tp registers. + */ +SYM_CODE_START(smpboot_entry) + li.d t0, CSR_DMW0_INIT # UC, PLV0 + csrwr t0, LOONGARCH_CSR_DMWIN0 + li.d t0, CSR_DMW1_INIT # CA, PLV0 + csrwr t0, LOONGARCH_CSR_DMWIN1 + li.w t0, 0xb0 # PLV=0, IE=0, PG=1 + csrwr t0, LOONGARCH_CSR_CRMD + li.w t0, 0x04 # PLV=0, PIE=1, PWE=0 + csrwr t0, LOONGARCH_CSR_PRMD + li.w t0, 0x00 # FPE=0, SXE=0, ASXE=0, BTE=0 + csrwr t0, LOONGARCH_CSR_EUEN + + la.abs t0, cpuboot_data + ld.d sp, t0, CPU_BOOT_STACK + ld.d tp, t0, CPU_BOOT_TINFO + + la.abs t0, 0f + jirl zero, t0, 0 +0: + bl start_secondary +SYM_CODE_END(smpboot_entry) + +#endif /* CONFIG_SMP */ + SYM_ENTRY(kernel_entry_end, SYM_L_GLOBAL, SYM_A_NONE) diff --git a/arch/loongarch/kernel/irq.c b/arch/loongarch/kernel/irq.c index 9bd07edf0bce..4b671d305ede 100644 --- a/arch/loongarch/kernel/irq.c +++ b/arch/loongarch/kernel/irq.c @@ -47,13 +47,17 @@ asmlinkage void spurious_interrupt(void) int arch_show_interrupts(struct seq_file *p, int prec) { +#ifdef CONFIG_SMP + show_ipi_list(p, prec); +#endif seq_printf(p, "%*s: %10u\n", prec, "ERR", atomic_read(&irq_err_count)); return 0; } void __init init_IRQ(void) { - int i; + int i, r, ipi_irq; + static int ipi_dummy_dev; unsigned int order = get_order(IRQ_STACK_SIZE); struct page *page; @@ -61,6 +65,13 @@ void __init init_IRQ(void) clear_csr_estat(ESTATF_IP); irqchip_init(); +#ifdef CONFIG_SMP + ipi_irq = EXCCODE_IPI - EXCCODE_INT_START; + irq_set_percpu_devid(ipi_irq); + r = request_percpu_irq(ipi_irq, loongson3_ipi_interrupt, "IPI", &ipi_dummy_dev); + if (r < 0) + panic("IPI IRQ request failed\n"); +#endif for (i = 0; i < NR_IRQS; i++) irq_set_noprobe(i); diff --git a/arch/loongarch/kernel/proc.c b/arch/loongarch/kernel/proc.c index d25592a29196..1effc73850fe 100644 --- a/arch/loongarch/kernel/proc.c +++ b/arch/loongarch/kernel/proc.c @@ -35,6 +35,11 @@ static int show_cpuinfo(struct seq_file *m, void *v) unsigned int fp_version = cpu_data[n].fpu_vers; struct proc_cpuinfo_notifier_args proc_cpuinfo_notifier_args; +#ifdef CONFIG_SMP + if (!cpu_online(n)) + return 0; +#endif + /* * For the first processor also print the system type */ diff --git a/arch/loongarch/kernel/process.c b/arch/loongarch/kernel/process.c index 54020223068f..6d944d65f600 100644 --- a/arch/loongarch/kernel/process.c +++ b/arch/loongarch/kernel/process.c @@ -53,6 +53,13 @@ unsigned long boot_option_idle_override = IDLE_NO_OVERRIDE; EXPORT_SYMBOL(boot_option_idle_override); +#ifdef CONFIG_HOTPLUG_CPU +void arch_cpu_idle_dead(void) +{ + play_dead(); +} +#endif + asmlinkage void ret_from_fork(void); asmlinkage void ret_from_kernel_thread(void); diff --git a/arch/loongarch/kernel/reset.c b/arch/loongarch/kernel/reset.c index ef484ce43c5c..2b86469e4718 100644 --- a/arch/loongarch/kernel/reset.c +++ b/arch/loongarch/kernel/reset.c @@ -65,16 +65,28 @@ EXPORT_SYMBOL(pm_power_off); void machine_halt(void) { +#ifdef CONFIG_SMP + preempt_disable(); + smp_send_stop(); +#endif default_halt(); } void machine_power_off(void) { +#ifdef CONFIG_SMP + preempt_disable(); + smp_send_stop(); +#endif pm_power_off(); } void machine_restart(char *command) { +#ifdef CONFIG_SMP + preempt_disable(); + smp_send_stop(); +#endif do_kernel_restart(command); pm_restart(); } diff --git a/arch/loongarch/kernel/setup.c b/arch/loongarch/kernel/setup.c index 29f3b82cd0a5..34a3011f679e 100644 --- a/arch/loongarch/kernel/setup.c +++ b/arch/loongarch/kernel/setup.c @@ -38,6 +38,7 @@ #include <asm/pgalloc.h> #include <asm/sections.h> #include <asm/setup.h> +#include <asm/smp.h> #include <asm/time.h> #define SMBIOS_BIOSSIZE_OFFSET 0x09 @@ -322,6 +323,29 @@ static int __init reserve_memblock_reserved_regions(void) } arch_initcall(reserve_memblock_reserved_regions); +#ifdef CONFIG_SMP +static void __init prefill_possible_map(void) +{ + int i, possible; + + possible = num_processors + disabled_cpus; + if (possible > nr_cpu_ids) + possible = nr_cpu_ids; + + pr_info("SMP: Allowing %d CPUs, %d hotplug CPUs\n", + possible, max((possible - num_processors), 0)); + + for (i = 0; i < possible; i++) + set_cpu_possible(i, true); + for (; i < NR_CPUS; i++) + set_cpu_possible(i, false); + + nr_cpu_ids = possible; +} +#else +static inline void prefill_possible_map(void) {} +#endif + void __init setup_arch(char **cmdline_p) { cpu_probe(); @@ -336,6 +360,8 @@ void __init setup_arch(char **cmdline_p) arch_mem_init(cmdline_p); resource_init(); + plat_smp_setup(); + prefill_possible_map(); paging_init(); } diff --git a/arch/loongarch/kernel/smp.c b/arch/loongarch/kernel/smp.c new file mode 100644 index 000000000000..99ba7a56edf9 --- /dev/null +++ b/arch/loongarch/kernel/smp.c @@ -0,0 +1,735 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited + * + * Derived from MIPS: + * Copyright (C) 2000, 2001 Kanoj Sarcar + * Copyright (C) 2000, 2001 Ralf Baechle + * Copyright (C) 2000, 2001 Silicon Graphics, Inc. + * Copyright (C) 2000, 2001, 2003 Broadcom Corporation + */ +#include <linux/cpu.h> +#include <linux/cpumask.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/seq_file.h> +#include <linux/smp.h> +#include <linux/threads.h> +#include <linux/export.h> +#include <linux/time.h> +#include <linux/tracepoint.h> +#include <linux/sched/hotplug.h> +#include <linux/sched/task_stack.h> + +#include <asm/cpu.h> +#include <asm/idle.h> +#include <asm/loongson.h> +#include <asm/mmu_context.h> +#include <asm/processor.h> +#include <asm/setup.h> +#include <asm/time.h> + +int __cpu_number_map[NR_CPUS]; /* Map physical to logical */ +EXPORT_SYMBOL(__cpu_number_map); + +int __cpu_logical_map[NR_CPUS]; /* Map logical to physical */ +EXPORT_SYMBOL(__cpu_logical_map); + +/* Number of threads (siblings) per CPU core */ +int smp_num_siblings = 1; +EXPORT_SYMBOL(smp_num_siblings); + +/* Representing the threads (siblings) of each logical CPU */ +cpumask_t cpu_sibling_map[NR_CPUS] __read_mostly; +EXPORT_SYMBOL(cpu_sibling_map); + +/* Representing the core map of multi-core chips of each logical CPU */ +cpumask_t cpu_core_map[NR_CPUS] __read_mostly; +EXPORT_SYMBOL(cpu_core_map); + +static DECLARE_COMPLETION(cpu_starting); +static DECLARE_COMPLETION(cpu_running); + +/* + * A logcal cpu mask containing only one VPE per core to + * reduce the number of IPIs on large MT systems. + */ +cpumask_t cpu_foreign_map[NR_CPUS] __read_mostly; +EXPORT_SYMBOL(cpu_foreign_map); + +/* representing cpus for which sibling maps can be computed */ +static cpumask_t cpu_sibling_setup_map; + +/* representing cpus for which core maps can be computed */ +static cpumask_t cpu_core_setup_map; + +struct secondary_data cpuboot_data; +static DEFINE_PER_CPU(int, cpu_state); +DEFINE_PER_CPU_SHARED_ALIGNED(irq_cpustat_t, irq_stat); +EXPORT_PER_CPU_SYMBOL(irq_stat); + +enum ipi_msg_type { + IPI_RESCHEDULE, + IPI_CALL_FUNCTION, +}; + +static const char *ipi_types[NR_IPI] __tracepoint_string = { + [IPI_RESCHEDULE] = "Rescheduling interrupts", + [IPI_CALL_FUNCTION] = "Function call interrupts", +}; + +void show_ipi_list(struct seq_file *p, int prec) +{ + unsigned int cpu, i; + + for (i = 0; i < NR_IPI; i++) { + seq_printf(p, "%*s%u:%s", prec - 1, "IPI", i, prec >= 4 ? " " : ""); + for_each_online_cpu(cpu) + seq_printf(p, "%10u ", per_cpu(irq_stat, cpu).ipi_irqs[i]); + seq_printf(p, " LoongArch %d %s\n", i + 1, ipi_types[i]); + } +} + +/* Send mailbox buffer via Mail_Send */ +static void csr_mail_send(uint64_t data, int cpu, int mailbox) +{ + uint64_t val; + + /* Send high 32 bits */ + val = IOCSR_MBUF_SEND_BLOCKING; + val |= (IOCSR_MBUF_SEND_BOX_HI(mailbox) << IOCSR_MBUF_SEND_BOX_SHIFT); + val |= (cpu << IOCSR_MBUF_SEND_CPU_SHIFT); + val |= (data & IOCSR_MBUF_SEND_H32_MASK); + iocsr_write64(val, LOONGARCH_IOCSR_MBUF_SEND); + + /* Send low 32 bits */ + val = IOCSR_MBUF_SEND_BLOCKING; + val |= (IOCSR_MBUF_SEND_BOX_LO(mailbox) << IOCSR_MBUF_SEND_BOX_SHIFT); + val |= (cpu << IOCSR_MBUF_SEND_CPU_SHIFT); + val |= (data << IOCSR_MBUF_SEND_BUF_SHIFT); + iocsr_write64(val, LOONGARCH_IOCSR_MBUF_SEND); +}; + +static u32 ipi_read_clear(int cpu) +{ + u32 action; + + /* Load the ipi register to figure out what we're supposed to do */ + action = iocsr_read32(LOONGARCH_IOCSR_IPI_STATUS); + /* Clear the ipi register to clear the interrupt */ + iocsr_write32(action, LOONGARCH_IOCSR_IPI_CLEAR); + smp_mb(); + + return action; +} + +static void ipi_write_action(int cpu, u32 action) +{ + unsigned int irq = 0; + + while ((irq = ffs(action))) { + uint32_t val = IOCSR_IPI_SEND_BLOCKING; + + val |= (irq - 1); + val |= (cpu << IOCSR_IPI_SEND_CPU_SHIFT); + iocsr_write32(val, LOONGARCH_IOCSR_IPI_SEND); + action &= ~BIT(irq - 1); + } +} + +void loongson3_send_ipi_single(int cpu, unsigned int action) +{ + ipi_write_action(cpu_logical_map(cpu), (u32)action); +} + +void loongson3_send_ipi_mask(const struct cpumask *mask, unsigned int action) +{ + unsigned int i; + + for_each_cpu(i, mask) + ipi_write_action(cpu_logical_map(i), (u32)action); +} + +irqreturn_t loongson3_ipi_interrupt(int irq, void *dev) +{ + unsigned int action; + unsigned int cpu = smp_processor_id(); + + action = ipi_read_clear(cpu_logical_map(cpu)); + + if (action & SMP_RESCHEDULE) { + scheduler_ipi(); + per_cpu(irq_stat, cpu).ipi_irqs[IPI_RESCHEDULE]++; + } + + if (action & SMP_CALL_FUNCTION) { + generic_smp_call_function_interrupt(); + per_cpu(irq_stat, cpu).ipi_irqs[IPI_CALL_FUNCTION]++; + } + + return IRQ_HANDLED; +} + +void __init loongson3_smp_setup(void) +{ + cpu_data[0].core = cpu_logical_map(0) % loongson_sysconf.cores_per_package; + cpu_data[0].package = cpu_logical_map(0) / loongson_sysconf.cores_per_package; + + iocsr_write32(0xffffffff, LOONGARCH_IOCSR_IPI_EN); + pr_info("Detected %i available CPU(s)\n", loongson_sysconf.nr_cpus); +} + +void __init loongson3_prepare_cpus(unsigned int max_cpus) +{ + int i = 0; + + for (i = 0; i < loongson_sysconf.nr_cpus; i++) { + set_cpu_present(i, true); + csr_mail_send(0, __cpu_logical_map[i], 0); + } + + per_cpu(cpu_state, smp_processor_id()) = CPU_ONLINE; +} + +/* + * Setup the PC, SP, and TP of a secondary processor and start it running! + */ +void loongson3_boot_secondary(int cpu, struct task_struct *idle) +{ + unsigned long entry; + + pr_info("Booting CPU#%d...\n", cpu); + + entry = __pa_symbol((unsigned long)&smpboot_entry); + cpuboot_data.stack = (unsigned long)__KSTK_TOS(idle); + cpuboot_data.thread_info = (unsigned long)task_thread_info(idle); + + csr_mail_send(entry, cpu_logical_map(cpu), 0); + + loongson3_send_ipi_single(cpu, SMP_BOOT_CPU); +} + +/* + * SMP init and finish on secondary CPUs + */ +void loongson3_init_secondary(void) +{ + unsigned int cpu = smp_processor_id(); + unsigned int imask = ECFGF_IP0 | ECFGF_IP1 | ECFGF_IP2 | + ECFGF_IPI | ECFGF_PMC | ECFGF_TIMER; + + change_csr_ecfg(ECFG0_IM, imask); + + iocsr_write32(0xffffffff, LOONGARCH_IOCSR_IPI_EN); + + per_cpu(cpu_state, cpu) = CPU_ONLINE; + cpu_data[cpu].core = + cpu_logical_map(cpu) % loongson_sysconf.cores_per_package; + cpu_data[cpu].package = + cpu_logical_map(cpu) / loongson_sysconf.cores_per_package; +} + +void loongson3_smp_finish(void) +{ + local_irq_enable(); + iocsr_write64(0, LOONGARCH_IOCSR_MBUF0); + pr_info("CPU#%d finished\n", smp_processor_id()); +} + +#ifdef CONFIG_HOTPLUG_CPU + +static bool io_master(int cpu) +{ + if (cpu == 0) + return true; + + return false; +} + +int loongson3_cpu_disable(void) +{ + unsigned long flags; + unsigned int cpu = smp_processor_id(); + + if (io_master(cpu)) + return -EBUSY; + + set_cpu_online(cpu, false); + calculate_cpu_foreign_map(); + local_irq_save(flags); + irq_migrate_all_off_this_cpu(); + clear_csr_ecfg(ECFG0_IM); + local_irq_restore(flags); + local_flush_tlb_all(); + + return 0; +} + +void loongson3_cpu_die(unsigned int cpu) +{ + while (per_cpu(cpu_state, cpu) != CPU_DEAD) + cpu_relax(); + + mb(); +} + +/* + * The target CPU should go to XKPRANGE (uncached area) and flush + * ICache/DCache/VCache before the control CPU can safely disable its clock. + */ +static void loongson3_play_dead(int *state_addr) +{ + register int val; + register void *addr; + register void (*init_fn)(void); + + __asm__ __volatile__( + " li.d %[addr], 0x8000000000000000\n" + "1: cacop 0x8, %[addr], 0 \n" /* flush ICache */ + " cacop 0x8, %[addr], 1 \n" + " cacop 0x8, %[addr], 2 \n" + " cacop 0x8, %[addr], 3 \n" + " cacop 0x9, %[addr], 0 \n" /* flush DCache */ + " cacop 0x9, %[addr], 1 \n" + " cacop 0x9, %[addr], 2 \n" + " cacop 0x9, %[addr], 3 \n" + " addi.w %[sets], %[sets], -1 \n" + " addi.d %[addr], %[addr], 0x40 \n" + " bnez %[sets], 1b \n" + " li.d %[addr], 0x8000000000000000\n" + "2: cacop 0xa, %[addr], 0 \n" /* flush VCache */ + " cacop 0xa, %[addr], 1 \n" + " cacop 0xa, %[addr], 2 \n" + " cacop 0xa, %[addr], 3 \n" + " cacop 0xa, %[addr], 4 \n" + " cacop 0xa, %[addr], 5 \n" + " cacop 0xa, %[addr], 6 \n" + " cacop 0xa, %[addr], 7 \n" + " cacop 0xa, %[addr], 8 \n" + " cacop 0xa, %[addr], 9 \n" + " cacop 0xa, %[addr], 10 \n" + " cacop 0xa, %[addr], 11 \n" + " cacop 0xa, %[addr], 12 \n" + " cacop 0xa, %[addr], 13 \n" + " cacop 0xa, %[addr], 14 \n" + " cacop 0xa, %[addr], 15 \n" + " addi.w %[vsets], %[vsets], -1 \n" + " addi.d %[addr], %[addr], 0x40 \n" + " bnez %[vsets], 2b \n" + " li.w %[val], 0x7 \n" /* *state_addr = CPU_DEAD; */ + " st.w %[val], %[state_addr], 0 \n" + " dbar 0 \n" + " cacop 0x11, %[state_addr], 0 \n" /* flush entry of *state_addr */ + : [addr] "=&r" (addr), [val] "=&r" (val) + : [state_addr] "r" (state_addr), + [sets] "r" (cpu_data[smp_processor_id()].dcache.sets), + [vsets] "r" (cpu_data[smp_processor_id()].vcache.sets)); + + local_irq_enable(); + change_csr_ecfg(ECFG0_IM, ECFGF_IPI); + + __asm__ __volatile__( + " idle 0 \n" + " li.w $t0, 0x1020 \n" + " iocsrrd.d %[init_fn], $t0 \n" /* Get init PC */ + : [init_fn] "=&r" (addr) + : /* No Input */ + : "a0"); + init_fn = __va(addr); + + init_fn(); + unreachable(); +} + +void play_dead(void) +{ + int *state_addr; + unsigned int cpu = smp_processor_id(); + void (*play_dead_uncached)(int *s); + + idle_task_exit(); + play_dead_uncached = (void *)TO_UNCACHE(__pa((unsigned long)loongson3_play_dead)); + state_addr = &per_cpu(cpu_state, cpu); + mb(); + play_dead_uncached(state_addr); +} + +static int loongson3_enable_clock(unsigned int cpu) +{ + uint64_t core_id = cpu_data[cpu].core; + uint64_t package_id = cpu_data[cpu].package; + + LOONGSON_FREQCTRL(package_id) |= 1 << (core_id * 4 + 3); + + return 0; +} + +static int loongson3_disable_clock(unsigned int cpu) +{ + uint64_t core_id = cpu_data[cpu].core; + uint64_t package_id = cpu_data[cpu].package; + + LOONGSON_FREQCTRL(package_id) &= ~(1 << (core_id * 4 + 3)); + + return 0; +} + +static int register_loongson3_notifier(void) +{ + return cpuhp_setup_state_nocalls(CPUHP_LOONGARCH_SOC_PREPARE, + "loongarch/loongson:prepare", + loongson3_enable_clock, + loongson3_disable_clock); +} +early_initcall(register_loongson3_notifier); + +#endif + +/* + * Power management + */ +#ifdef CONFIG_PM + +static int loongson3_ipi_suspend(void) +{ + return 0; +} + +static void loongson3_ipi_resume(void) +{ + iocsr_write32(0xffffffff, LOONGARCH_IOCSR_IPI_EN); +} + +static struct syscore_ops loongson3_ipi_syscore_ops = { + .resume = loongson3_ipi_resume, + .suspend = loongson3_ipi_suspend, +}; + +/* + * Enable boot cpu ipi before enabling nonboot cpus + * during syscore_resume. + */ +static int __init ipi_pm_init(void) +{ + register_syscore_ops(&loongson3_ipi_syscore_ops); + return 0; +} + +core_initcall(ipi_pm_init); +#endif + +static inline void set_cpu_sibling_map(int cpu) +{ + int i; + + cpumask_set_cpu(cpu, &cpu_sibling_setup_map); + + if (smp_num_siblings <= 1) + cpumask_set_cpu(cpu, &cpu_sibling_map[cpu]); + else { + for_each_cpu(i, &cpu_sibling_setup_map) { + if (cpus_are_siblings(cpu, i)) { + cpumask_set_cpu(i, &cpu_sibling_map[cpu]); + cpumask_set_cpu(cpu, &cpu_sibling_map[i]); + } + } + } +} + +static inline void set_cpu_core_map(int cpu) +{ + int i; + + cpumask_set_cpu(cpu, &cpu_core_setup_map); + + for_each_cpu(i, &cpu_core_setup_map) { + if (cpu_data[cpu].package == cpu_data[i].package) { + cpumask_set_cpu(i, &cpu_core_map[cpu]); + cpumask_set_cpu(cpu, &cpu_core_map[i]); + } + } +} + +/* + * Calculate a new cpu_foreign_map mask whenever a + * new cpu appears or disappears. + */ +void calculate_cpu_foreign_map(void) +{ + int i, k, core_present; + cpumask_t temp_foreign_map; + + /* Re-calculate the mask */ + cpumask_clear(&temp_foreign_map); + for_each_online_cpu(i) { + core_present = 0; + for_each_cpu(k, &temp_foreign_map) + if (cpus_are_siblings(i, k)) + core_present = 1; + if (!core_present) + cpumask_set_cpu(i, &temp_foreign_map); + } + + for_each_online_cpu(i) + cpumask_andnot(&cpu_foreign_map[i], + &temp_foreign_map, &cpu_sibling_map[i]); +} + +/* Preload SMP state for boot cpu */ +void smp_prepare_boot_cpu(void) +{ + unsigned int cpu; + + set_cpu_possible(0, true); + set_cpu_online(0, true); + set_my_cpu_offset(per_cpu_offset(0)); + + for_each_possible_cpu(cpu) + set_cpu_numa_node(cpu, 0); +} + +/* called from main before smp_init() */ +void __init smp_prepare_cpus(unsigned int max_cpus) +{ + init_new_context(current, &init_mm); + current_thread_info()->cpu = 0; + loongson3_prepare_cpus(max_cpus); + set_cpu_sibling_map(0); + set_cpu_core_map(0); + calculate_cpu_foreign_map(); +#ifndef CONFIG_HOTPLUG_CPU + init_cpu_present(cpu_possible_mask); +#endif +} + +int __cpu_up(unsigned int cpu, struct task_struct *tidle) +{ + loongson3_boot_secondary(cpu, tidle); + + /* Wait for CPU to start and be ready to sync counters */ + if (!wait_for_completion_timeout(&cpu_starting, + msecs_to_jiffies(5000))) { + pr_crit("CPU%u: failed to start\n", cpu); + return -EIO; + } + + /* Wait for CPU to finish startup & mark itself online before return */ + wait_for_completion(&cpu_running); + + return 0; +} + +/* + * First C code run on the secondary CPUs after being started up by + * the master. + */ +asmlinkage void start_secondary(void) +{ + unsigned int cpu; + + sync_counter(); + cpu = smp_processor_id(); + set_my_cpu_offset(per_cpu_offset(cpu)); + + cpu_probe(); + constant_clockevent_init(); + loongson3_init_secondary(); + + set_cpu_sibling_map(cpu); + set_cpu_core_map(cpu); + + notify_cpu_starting(cpu); + + /* Notify boot CPU that we're starting */ + complete(&cpu_starting); + + /* The CPU is running, now mark it online */ + set_cpu_online(cpu, true); + + calculate_cpu_foreign_map(); + + /* + * Notify boot CPU that we're up & online and it can safely return + * from __cpu_up() + */ + complete(&cpu_running); + + /* + * irq will be enabled in loongson3_smp_finish(), enabling it too + * early is dangerous. + */ + WARN_ON_ONCE(!irqs_disabled()); + loongson3_smp_finish(); + + cpu_startup_entry(CPUHP_AP_ONLINE_IDLE); +} + +void __init smp_cpus_done(unsigned int max_cpus) +{ +} + +static void stop_this_cpu(void *dummy) +{ + set_cpu_online(smp_processor_id(), false); + calculate_cpu_foreign_map(); + local_irq_disable(); + while (true); +} + +void smp_send_stop(void) +{ + smp_call_function(stop_this_cpu, NULL, 0); +} + +int setup_profiling_timer(unsigned int multiplier) +{ + return 0; +} + +static void flush_tlb_all_ipi(void *info) +{ + local_flush_tlb_all(); +} + +void flush_tlb_all(void) +{ + on_each_cpu(flush_tlb_all_ipi, NULL, 1); +} + +static void flush_tlb_mm_ipi(void *mm) +{ + local_flush_tlb_mm((struct mm_struct *)mm); +} + +void flush_tlb_mm(struct mm_struct *mm) +{ + if (atomic_read(&mm->mm_users) == 0) + return; /* happens as a result of exit_mmap() */ + + preempt_disable(); + + if ((atomic_read(&mm->mm_users) != 1) || (current->mm != mm)) { + on_each_cpu_mask(mm_cpumask(mm), flush_tlb_mm_ipi, mm, 1); + } else { + unsigned int cpu; + + for_each_online_cpu(cpu) { + if (cpu != smp_processor_id() && cpu_context(cpu, mm)) + cpu_context(cpu, mm) = 0; + } + local_flush_tlb_mm(mm); + } + + preempt_enable(); +} + +struct flush_tlb_data { + struct vm_area_struct *vma; + unsigned long addr1; + unsigned long addr2; +}; + +static void flush_tlb_range_ipi(void *info) +{ + struct flush_tlb_data *fd = info; + + local_flush_tlb_range(fd->vma, fd->addr1, fd->addr2); +} + +void flush_tlb_range(struct vm_area_struct *vma, unsigned long start, unsigned long end) +{ + struct mm_struct *mm = vma->vm_mm; + + preempt_disable(); + if ((atomic_read(&mm->mm_users) != 1) || (current->mm != mm)) { + struct flush_tlb_data fd = { + .vma = vma, + .addr1 = start, + .addr2 = end, + }; + + on_each_cpu_mask(mm_cpumask(mm), flush_tlb_range_ipi, &fd, 1); + } else { + unsigned int cpu; + int exec = vma->vm_flags & VM_EXEC; + + for_each_online_cpu(cpu) { + /* + * flush_cache_range() will only fully flush icache if + * the VMA is executable, otherwise we must invalidate + * ASID without it appearing to has_valid_asid() as if + * mm has been completely unused by that CPU. + */ + if (cpu != smp_processor_id() && cpu_context(cpu, mm)) + cpu_context(cpu, mm) = !exec; + } + local_flush_tlb_range(vma, start, end); + } + preempt_enable(); +} + +static void flush_tlb_kernel_range_ipi(void *info) +{ + struct flush_tlb_data *fd = info; + + local_flush_tlb_kernel_range(fd->addr1, fd->addr2); +} + +void flush_tlb_kernel_range(unsigned long start, unsigned long end) +{ + struct flush_tlb_data fd = { + .addr1 = start, + .addr2 = end, + }; + + on_each_cpu(flush_tlb_kernel_range_ipi, &fd, 1); +} + +static void flush_tlb_page_ipi(void *info) +{ + struct flush_tlb_data *fd = info; + + local_flush_tlb_page(fd->vma, fd->addr1); +} + +void flush_tlb_page(struct vm_area_struct *vma, unsigned long page) +{ + preempt_disable(); + if ((atomic_read(&vma->vm_mm->mm_users) != 1) || (current->mm != vma->vm_mm)) { + struct flush_tlb_data fd = { + .vma = vma, + .addr1 = page, + }; + + on_each_cpu_mask(mm_cpumask(vma->vm_mm), flush_tlb_page_ipi, &fd, 1); + } else { + unsigned int cpu; + + for_each_online_cpu(cpu) { + /* + * flush_cache_page() only does partial flushes, so + * invalidate ASID without it appearing to + * has_valid_asid() as if mm has been completely unused + * by that CPU. + */ + if (cpu != smp_processor_id() && cpu_context(cpu, vma->vm_mm)) + cpu_context(cpu, vma->vm_mm) = 1; + } + local_flush_tlb_page(vma, page); + } + preempt_enable(); +} +EXPORT_SYMBOL(flush_tlb_page); + +static void flush_tlb_one_ipi(void *info) +{ + unsigned long vaddr = (unsigned long) info; + + local_flush_tlb_one(vaddr); +} + +void flush_tlb_one(unsigned long vaddr) +{ + on_each_cpu(flush_tlb_one_ipi, (void *)vaddr, 1); +} +EXPORT_SYMBOL(flush_tlb_one); diff --git a/arch/loongarch/kernel/topology.c b/arch/loongarch/kernel/topology.c index 3b2cbb95875b..ab1a75c0b5a6 100644 --- a/arch/loongarch/kernel/topology.c +++ b/arch/loongarch/kernel/topology.c @@ -1,13 +1,52 @@ // SPDX-License-Identifier: GPL-2.0 #include <linux/cpu.h> +#include <linux/cpumask.h> #include <linux/init.h> +#include <linux/node.h> +#include <linux/nodemask.h> #include <linux/percpu.h> -static struct cpu cpu_device; +static DEFINE_PER_CPU(struct cpu, cpu_devices); + +#ifdef CONFIG_HOTPLUG_CPU +int arch_register_cpu(int cpu) +{ + int ret; + struct cpu *c = &per_cpu(cpu_devices, cpu); + + c->hotpluggable = 1; + ret = register_cpu(c, cpu); + if (ret < 0) + pr_warn("register_cpu %d failed (%d)\n", cpu, ret); + + return ret; +} +EXPORT_SYMBOL(arch_register_cpu); + +void arch_unregister_cpu(int cpu) +{ + struct cpu *c = &per_cpu(cpu_devices, cpu); + + c->hotpluggable = 0; + unregister_cpu(c); +} +EXPORT_SYMBOL(arch_unregister_cpu); +#endif static int __init topology_init(void) { - return register_cpu(&cpu_device, 0); + int i, ret; + + for_each_present_cpu(i) { + struct cpu *c = &per_cpu(cpu_devices, i); + + c->hotpluggable = !!i; + ret = register_cpu(c, i); + if (ret < 0) + pr_warn("topology_init: register_cpu %d failed (%d)\n", i, ret); + } + + return 0; } subsys_initcall(topology_init); diff --git a/arch/loongarch/kernel/vmlinux.lds.S b/arch/loongarch/kernel/vmlinux.lds.S index 7da4c4d7c50d..006cbb1bd5c6 100644 --- a/arch/loongarch/kernel/vmlinux.lds.S +++ b/arch/loongarch/kernel/vmlinux.lds.S @@ -73,6 +73,10 @@ SECTIONS EXIT_DATA } +#ifdef CONFIG_SMP + PERCPU_SECTION(1 << CONFIG_L1_CACHE_SHIFT) +#endif + .init.bss : { *(.init.bss) } diff --git a/arch/loongarch/mm/tlbex.S b/arch/loongarch/mm/tlbex.S index bef740710a3b..7eee40271577 100644 --- a/arch/loongarch/mm/tlbex.S +++ b/arch/loongarch/mm/tlbex.S @@ -88,7 +88,14 @@ vmalloc_done_load: slli.d t0, t0, _PTE_T_LOG2 add.d t1, ra, t0 +#ifdef CONFIG_SMP +smp_pgtable_change_load: +#endif +#ifdef CONFIG_SMP + ll.d t0, t1, 0 +#else ld.d t0, t1, 0 +#endif tlbsrch srli.d ra, t0, _PAGE_PRESENT_SHIFT @@ -96,7 +103,12 @@ vmalloc_done_load: beq ra, $r0, nopage_tlb_load ori t0, t0, _PAGE_VALID +#ifdef CONFIG_SMP + sc.d t0, t1, 0 + beq t0, $r0, smp_pgtable_change_load +#else st.d t0, t1, 0 +#endif ori t1, t1, 8 xori t1, t1, 8 ld.d t0, t1, 0 @@ -120,14 +132,24 @@ vmalloc_load: * spots a huge page. */ tlb_huge_update_load: +#ifdef CONFIG_SMP + ll.d t0, t1, 0 +#else ld.d t0, t1, 0 +#endif srli.d ra, t0, _PAGE_PRESENT_SHIFT andi ra, ra, 1 beq ra, $r0, nopage_tlb_load tlbsrch ori t0, t0, _PAGE_VALID +#ifdef CONFIG_SMP + sc.d t0, t1, 0 + beq t0, $r0, tlb_huge_update_load + ld.d t0, t1, 0 +#else st.d t0, t1, 0 +#endif addu16i.d t1, $r0, -(CSR_TLBIDX_EHINV >> 16) addi.d ra, t1, 0 csrxchg ra, t1, LOONGARCH_CSR_TLBIDX @@ -173,6 +195,7 @@ tlb_huge_update_load: csrxchg t1, t0, LOONGARCH_CSR_TLBIDX nopage_tlb_load: + dbar 0 csrrd ra, EXCEPTION_KS2 la.abs t0, tlb_do_page_fault_0 jirl $r0, t0, 0 @@ -229,7 +252,14 @@ vmalloc_done_store: slli.d t0, t0, _PTE_T_LOG2 add.d t1, ra, t0 +#ifdef CONFIG_SMP +smp_pgtable_change_store: +#endif +#ifdef CONFIG_SMP + ll.d t0, t1, 0 +#else ld.d t0, t1, 0 +#endif tlbsrch srli.d ra, t0, _PAGE_PRESENT_SHIFT @@ -238,7 +268,12 @@ vmalloc_done_store: bne ra, $r0, nopage_tlb_store ori t0, t0, (_PAGE_VALID | _PAGE_DIRTY | _PAGE_MODIFIED) +#ifdef CONFIG_SMP + sc.d t0, t1, 0 + beq t0, $r0, smp_pgtable_change_store +#else st.d t0, t1, 0 +#endif ori t1, t1, 8 xori t1, t1, 8 @@ -263,7 +298,11 @@ vmalloc_store: * spots a huge page. */ tlb_huge_update_store: +#ifdef CONFIG_SMP + ll.d t0, t1, 0 +#else ld.d t0, t1, 0 +#endif srli.d ra, t0, _PAGE_PRESENT_SHIFT andi ra, ra, ((_PAGE_PRESENT | _PAGE_WRITE) >> _PAGE_PRESENT_SHIFT) xori ra, ra, ((_PAGE_PRESENT | _PAGE_WRITE) >> _PAGE_PRESENT_SHIFT) @@ -272,7 +311,13 @@ tlb_huge_update_store: tlbsrch ori t0, t0, (_PAGE_VALID | _PAGE_DIRTY | _PAGE_MODIFIED) +#ifdef CONFIG_SMP + sc.d t0, t1, 0 + beq t0, $r0, tlb_huge_update_store + ld.d t0, t1, 0 +#else st.d t0, t1, 0 +#endif addu16i.d t1, $r0, -(CSR_TLBIDX_EHINV >> 16) addi.d ra, t1, 0 csrxchg ra, t1, LOONGARCH_CSR_TLBIDX @@ -318,6 +363,7 @@ tlb_huge_update_store: csrxchg t1, t0, LOONGARCH_CSR_TLBIDX nopage_tlb_store: + dbar 0 csrrd ra, EXCEPTION_KS2 la.abs t0, tlb_do_page_fault_1 jirl $r0, t0, 0 @@ -373,7 +419,14 @@ vmalloc_done_modify: slli.d t0, t0, _PTE_T_LOG2 add.d t1, ra, t0 +#ifdef CONFIG_SMP +smp_pgtable_change_modify: +#endif +#ifdef CONFIG_SMP + ll.d t0, t1, 0 +#else ld.d t0, t1, 0 +#endif tlbsrch srli.d ra, t0, _PAGE_WRITE_SHIFT @@ -381,7 +434,12 @@ vmalloc_done_modify: beq ra, $r0, nopage_tlb_modify ori t0, t0, (_PAGE_VALID | _PAGE_DIRTY | _PAGE_MODIFIED) +#ifdef CONFIG_SMP + sc.d t0, t1, 0 + beq t0, $r0, smp_pgtable_change_modify +#else st.d t0, t1, 0 +#endif ori t1, t1, 8 xori t1, t1, 8 ld.d t0, t1, 0 @@ -405,7 +463,11 @@ vmalloc_modify: * build_tlbchange_handler_head spots a huge page. */ tlb_huge_update_modify: +#ifdef CONFIG_SMP + ll.d t0, t1, 0 +#else ld.d t0, t1, 0 +#endif srli.d ra, t0, _PAGE_WRITE_SHIFT andi ra, ra, 1 @@ -414,7 +476,13 @@ tlb_huge_update_modify: tlbsrch ori t0, t0, (_PAGE_VALID | _PAGE_DIRTY | _PAGE_MODIFIED) +#ifdef CONFIG_SMP + sc.d t0, t1, 0 + beq t0, $r0, tlb_huge_update_modify + ld.d t0, t1, 0 +#else st.d t0, t1, 0 +#endif /* * A huge PTE describes an area the size of the * configured huge page size. This is twice the @@ -454,6 +522,7 @@ tlb_huge_update_modify: csrxchg t1, t0, LOONGARCH_CSR_TLBIDX nopage_tlb_modify: + dbar 0 csrrd ra, EXCEPTION_KS2 la.abs t0, tlb_do_page_fault_1 jirl $r0, t0, 0 diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h index b66c5f389159..19f0dbfdd7fe 100644 --- a/include/linux/cpuhotplug.h +++ b/include/linux/cpuhotplug.h @@ -130,6 +130,7 @@ enum cpuhp_state { CPUHP_ZCOMP_PREPARE, CPUHP_TIMERS_PREPARE, CPUHP_MIPS_SOC_PREPARE, + CPUHP_LOONGARCH_SOC_PREPARE, CPUHP_BP_PREPARE_DYN, CPUHP_BP_PREPARE_DYN_END = CPUHP_BP_PREPARE_DYN + 20, CPUHP_BRINGUP_CPU, -- 2.27.0
