diff options
| -rw-r--r-- | arch/mips/include/asm/mips-cm.h | 32 | ||||
| -rw-r--r-- | arch/mips/kernel/mips-cm.c | 39 |
2 files changed, 71 insertions, 0 deletions
diff --git a/arch/mips/include/asm/mips-cm.h b/arch/mips/include/asm/mips-cm.h index 7740c4f44289..6516e9da5133 100644 --- a/arch/mips/include/asm/mips-cm.h +++ b/arch/mips/include/asm/mips-cm.h @@ -364,6 +364,10 @@ BUILD_CM_Cx_R_(tcid_8_priority, 0x80) /* GCR_Cx_OTHER register fields */ #define CM_GCR_Cx_OTHER_CORENUM_SHF 16 #define CM_GCR_Cx_OTHER_CORENUM_MSK (_ULCAST_(0xffff) << 16) +#define CM3_GCR_Cx_OTHER_CORE_SHF 8 +#define CM3_GCR_Cx_OTHER_CORE_MSK (_ULCAST_(0x3f) << 8) +#define CM3_GCR_Cx_OTHER_VP_SHF 0 +#define CM3_GCR_Cx_OTHER_VP_MSK (_ULCAST_(0x7) << 0) /* GCR_Cx_RESET_BASE register fields */ #define CM_GCR_Cx_RESET_BASE_BEVEXCBASE_SHF 12 @@ -474,4 +478,32 @@ static inline unsigned int mips_cm_vp_id(unsigned int cpu) return (core * mips_cm_max_vp_width()) + vp; } +#ifdef CONFIG_MIPS_CM + +/** + * mips_cm_lock_other - lock access to another core + * @core: the other core to be accessed + * @vp: the VP within 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_cm_unlock_other. + */ +extern void mips_cm_lock_other(unsigned int core, unsigned int vp); + +/** + * mips_cm_unlock_other - unlock access to another core + * + * Call after operating upon another core via the 'other' register region. + * Must be called after mips_cm_lock_other. + */ +extern void mips_cm_unlock_other(void); + +#else /* !CONFIG_MIPS_CM */ + +static inline void mips_cm_lock_other(unsigned int core) { } +static inline void mips_cm_unlock_other(void) { } + +#endif /* !CONFIG_MIPS_CM */ + #endif /* __MIPS_ASM_MIPS_CM_H__ */ diff --git a/arch/mips/kernel/mips-cm.c b/arch/mips/kernel/mips-cm.c index 02f7d7a41133..01908dbdf677 100644 --- a/arch/mips/kernel/mips-cm.c +++ b/arch/mips/kernel/mips-cm.c @@ -9,6 +9,8 @@ */ #include <linux/errno.h> +#include <linux/percpu.h> +#include <linux/spinlock.h> #include <asm/mips-cm.h> #include <asm/mipsregs.h> @@ -136,6 +138,9 @@ static char *cm3_causes[32] = { "0x19", "0x1a", "0x1b", "0x1c", "0x1d", "0x1e", "0x1f" }; +static DEFINE_PER_CPU_ALIGNED(spinlock_t, cm_core_lock); +static DEFINE_PER_CPU_ALIGNED(unsigned long, cm_core_lock_flags); + phys_addr_t __mips_cm_phys_base(void) { u32 config3 = read_c0_config3(); @@ -200,6 +205,7 @@ int mips_cm_probe(void) { phys_addr_t addr; u32 base_reg; + unsigned cpu; /* * No need to probe again if we have already been @@ -247,9 +253,42 @@ int mips_cm_probe(void) /* determine register width for this CM */ mips_cm_is64 = config_enabled(CONFIG_64BIT) && (mips_cm_revision() >= CM_REV_CM3); + for_each_possible_cpu(cpu) + spin_lock_init(&per_cpu(cm_core_lock, cpu)); + return 0; } +void mips_cm_lock_other(unsigned int core, unsigned int vp) +{ + unsigned curr_core; + u32 val; + + preempt_disable(); + curr_core = current_cpu_data.core; + spin_lock_irqsave(&per_cpu(cm_core_lock, curr_core), + per_cpu(cm_core_lock_flags, curr_core)); + + if (mips_cm_revision() >= CM_REV_CM3) { + val = core << CM3_GCR_Cx_OTHER_CORE_SHF; + val |= vp << CM3_GCR_Cx_OTHER_VP_SHF; + } else { + BUG_ON(vp != 0); + val = core << CM_GCR_Cx_OTHER_CORENUM_SHF; + } + + write_gcr_cl_other(val); +} + +void mips_cm_unlock_other(void) +{ + unsigned curr_core = current_cpu_data.core; + + spin_unlock_irqrestore(&per_cpu(cm_core_lock, curr_core), + per_cpu(cm_core_lock_flags, curr_core)); + preempt_enable(); +} + void mips_cm_error_report(void) { u64 cm_error, cm_addr, cm_other; |