diff options
| -rw-r--r-- | arch/mips/include/asm/mips-cpc.h | 27 | ||||
| -rw-r--r-- | arch/mips/kernel/mips-cpc.c | 26 |
2 files changed, 53 insertions, 0 deletions
diff --git a/arch/mips/include/asm/mips-cpc.h b/arch/mips/include/asm/mips-cpc.h index c5bb609..e139a53 100644 --- a/arch/mips/include/asm/mips-cpc.h +++ b/arch/mips/include/asm/mips-cpc.h @@ -152,4 +152,31 @@ BUILD_CPC_Cx_RW(other, 0x10) #define CPC_Cx_OTHER_CORENUM_SHF 16 #define CPC_Cx_OTHER_CORENUM_MSK (_ULCAST_(0xff) << 16) +#ifdef CONFIG_MIPS_CPC + +/** + * mips_cpc_lock_other - lock access to another core + * core: the other core to be accessed + * + * Call before operating upon a core via the 'other' register region in + * order to prevent the region being moved during access. Must be followed + * by a call to mips_cpc_unlock_other. + */ +extern void mips_cpc_lock_other(unsigned int core); + +/** + * mips_cpc_unlock_other - unlock access to another core + * + * Call after operating upon another core via the 'other' register region. + * Must be called after mips_cpc_lock_other. + */ +extern void mips_cpc_unlock_other(void); + +#else /* !CONFIG_MIPS_CPC */ + +static inline void mips_cpc_lock_other(unsigned int core) { } +static inline void mips_cpc_unlock_other(void) { } + +#endif /* !CONFIG_MIPS_CPC */ + #endif /* __MIPS_ASM_MIPS_CPC_H__ */ diff --git a/arch/mips/kernel/mips-cpc.c b/arch/mips/kernel/mips-cpc.c index c9dc674..2368fc5 100644 --- a/arch/mips/kernel/mips-cpc.c +++ b/arch/mips/kernel/mips-cpc.c @@ -15,6 +15,10 @@ void __iomem *mips_cpc_base; +static DEFINE_PER_CPU_ALIGNED(spinlock_t, cpc_core_lock); + +static DEFINE_PER_CPU_ALIGNED(unsigned long, cpc_core_lock_flags); + phys_t __weak mips_cpc_phys_base(void) { u32 cpc_base; @@ -39,6 +43,10 @@ phys_t __weak mips_cpc_phys_base(void) int mips_cpc_probe(void) { phys_t addr; + unsigned cpu; + + for_each_possible_cpu(cpu) + spin_lock_init(&per_cpu(cpc_core_lock, cpu)); addr = mips_cpc_phys_base(); if (!addr) @@ -50,3 +58,21 @@ int mips_cpc_probe(void) return 0; } + +void mips_cpc_lock_other(unsigned int core) +{ + unsigned curr_core; + preempt_disable(); + curr_core = current_cpu_data.core; + spin_lock_irqsave(&per_cpu(cpc_core_lock, curr_core), + per_cpu(cpc_core_lock_flags, curr_core)); + write_cpc_cl_other(core << CPC_Cx_OTHER_CORENUM_SHF); +} + +void mips_cpc_unlock_other(void) +{ + unsigned curr_core = current_cpu_data.core; + spin_unlock_irqrestore(&per_cpu(cpc_core_lock, curr_core), + per_cpu(cpc_core_lock_flags, curr_core)); + preempt_enable(); +} |