From 68923cdc2eb34124d77bc27f7945d7ff16b236dd Mon Sep 17 00:00:00 2001 From: Paul Burton Date: Sat, 12 Aug 2017 19:49:39 -0700 Subject: MIPS: CM: Add cluster & block args to mips_cm_lock_other() With CM >= 3.5 we have the notion of multiple clusters & can access their CM, CPC & GIC registers via the apporpriate redirect/other register blocks. In order to allow for this introduce cluster & block arguments to mips_cm_lock_other() which configures the redirect/other region to point at the appropriate cluster, core, VP & register block. Since we now have 4 arguments to mips_cm_lock_other() & a common use is likely to be to target the cluster, core & VP corresponding to a particular Linux CPU number we also add a new mips_cm_lock_other_cpu() helper function which handles that without the caller needing to manually pull out the cluster, core & VP numbers. Signed-off-by: Paul Burton Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17013/ Signed-off-by: Ralf Baechle --- arch/mips/include/asm/mips-cm.h | 45 ++++++++++++++++++++++++++++++++--------- 1 file changed, 36 insertions(+), 9 deletions(-) (limited to 'arch/mips/include') diff --git a/arch/mips/include/asm/mips-cm.h b/arch/mips/include/asm/mips-cm.h index 6cfc0cc265d7..d42cc8e76dc2 100644 --- a/arch/mips/include/asm/mips-cm.h +++ b/arch/mips/include/asm/mips-cm.h @@ -437,29 +437,56 @@ static inline unsigned int mips_cm_vp_id(unsigned int cpu) #ifdef CONFIG_MIPS_CM /** - * mips_cm_lock_other - lock access to another core + * mips_cm_lock_other - lock access to redirect/other region + * @cluster: the other cluster to be accessed * @core: the other core to be accessed * @vp: the VP within the other core to be accessed + * @block: the register block 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. + * Configure the redirect/other region for the local core/VP (depending upon + * the CM revision) to target the specified @cluster, @core, @vp & register + * @block. Must be called before using the redirect/other region, and followed + * by a call to mips_cm_unlock_other() when access to the redirect/other region + * is complete. + * + * This function acquires a spinlock such that code between it & + * mips_cm_unlock_other() calls cannot be pre-empted by anything which may + * reconfigure the redirect/other region, and cannot be interfered with by + * another VP in the core. As such calls to this function should not be nested. */ -extern void mips_cm_lock_other(unsigned int core, unsigned int vp); +extern void mips_cm_lock_other(unsigned int cluster, unsigned int core, + unsigned int vp, unsigned int block); /** - * mips_cm_unlock_other - unlock access to another core + * mips_cm_unlock_other - unlock access to redirect/other region * - * Call after operating upon another core via the 'other' register region. - * Must be called after mips_cm_lock_other. + * Must be called after mips_cm_lock_other() once all required access to the + * redirect/other region has been completed. */ extern void mips_cm_unlock_other(void); #else /* !CONFIG_MIPS_CM */ -static inline void mips_cm_lock_other(unsigned int core, unsigned int vp) { } +static inline void mips_cm_lock_other(unsigned int cluster, unsigned int core, + unsigned int vp, unsigned int block) { } static inline void mips_cm_unlock_other(void) { } #endif /* !CONFIG_MIPS_CM */ +/** + * mips_cm_lock_other_cpu - lock access to redirect/other region + * @cpu: the other CPU whose register we want to access + * + * Configure the redirect/other region for the local core/VP (depending upon + * the CM revision) to target the specified @cpu & register @block. This is + * equivalent to calling mips_cm_lock_other() but accepts a Linux CPU number + * for convenience. + */ +static inline void mips_cm_lock_other_cpu(unsigned int cpu, unsigned int block) +{ + struct cpuinfo_mips *d = &cpu_data[cpu]; + + mips_cm_lock_other(cpu_cluster(d), cpu_core(d), cpu_vpe_id(d), block); +} + #endif /* __MIPS_ASM_MIPS_CM_H__ */ -- cgit v1.2.3