From db2b0d76cdc4e781d32bf26d0c649ca2fe608c4e Mon Sep 17 00:00:00 2001 From: Helge Deller Date: Tue, 29 Mar 2022 14:15:29 +0200 Subject: parisc: Add PDC locking functions for rendezvous code Add pdc_cpu_rendezvous_lock() and pdc_cpu_rendezvous_unlock() to lock PDC while CPU is transitioning into rendezvous state. This is needed, because the transition phase may take up to 8 seconds. Add pdc_pat_get_PDC_entrypoint() to get PDC entry point for current CPU. Signed-off-by: Helge Deller --- arch/parisc/kernel/firmware.c | 37 +++++++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) (limited to 'arch/parisc/kernel') diff --git a/arch/parisc/kernel/firmware.c b/arch/parisc/kernel/firmware.c index c6b11bdb8602..6a7e315bcc2e 100644 --- a/arch/parisc/kernel/firmware.c +++ b/arch/parisc/kernel/firmware.c @@ -329,7 +329,44 @@ int __pdc_cpu_rendezvous(void) return mem_pdc_call(PDC_PROC, 1, 0); } +/** + * pdc_cpu_rendezvous_lock - Lock PDC while transitioning to rendezvous state + */ +void pdc_cpu_rendezvous_lock(void) +{ + spin_lock(&pdc_lock); +} + +/** + * pdc_cpu_rendezvous_unlock - Unlock PDC after reaching rendezvous state + */ +void pdc_cpu_rendezvous_unlock(void) +{ + spin_unlock(&pdc_lock); +} + +/** + * pdc_pat_get_PDC_entrypoint - Get PDC entry point for current CPU + * @retval: -1 on error, 0 on success + */ +int pdc_pat_get_PDC_entrypoint(unsigned long *pdc_entry) +{ + int retval = 0; + unsigned long flags; + + if (!IS_ENABLED(CONFIG_SMP) || !is_pdc_pat()) { + *pdc_entry = MEM_PDC; + return 0; + } + + spin_lock_irqsave(&pdc_lock, flags); + retval = mem_pdc_call(PDC_PAT_CPU, PDC_PAT_CPU_GET_PDC_ENTRYPOINT, + __pa(pdc_result)); + *pdc_entry = pdc_result[0]; + spin_unlock_irqrestore(&pdc_lock, flags); + return retval; +} /** * pdc_chassis_warn - Fetches chassis warnings * @retval: -1 on error, 0 on success -- cgit