-
-/*
- * the following functions deal with sending IPIs between CPUs.
- *
- * We use 'broadcast', CPU->CPU IPIs and self-IPIs too.
- */
-
-static inline unsigned int __prepare_ICR (unsigned int shortcut, int vector)
-{
- unsigned int icr = APIC_DM_FIXED | shortcut | vector | APIC_DEST_LOGICAL;
- if (vector == KDB_VECTOR)
- icr = (icr & (~APIC_VECTOR_MASK)) | APIC_DM_NMI;
- return icr;
-}
-
-static inline int __prepare_ICR2 (unsigned int mask)
-{
- return SET_APIC_DEST_FIELD(mask);
-}
-
-static inline void __send_IPI_shortcut(unsigned int shortcut, int vector)
-{
- /*
- * Subtle. In the case of the 'never do double writes' workaround
- * we have to lock out interrupts to be safe. As we don't care
- * of the value read we use an atomic rmw access to avoid costly
- * cli/sti. Otherwise we use an even cheaper single atomic write
- * to the APIC.
- */
- unsigned int cfg;
-
- /*
- * Wait for idle.
- */
- apic_wait_icr_idle();
-
- /*
- * No need to touch the target chip field
- */
- cfg = __prepare_ICR(shortcut, vector);
-
- /*
- * Send the IPI. The write to APIC_ICR fires this off.
- */
- apic_write_around(APIC_ICR, cfg);
-}
-
-static inline void send_IPI_allbutself(int vector)
-{
- /*
- * if there are no other CPUs in the system then
- * we get an APIC send error if we try to broadcast.
- * thus we have to avoid sending IPIs in this case.
- */
- if (num_online_cpus() > 1)
- __send_IPI_shortcut(APIC_DEST_ALLBUT, vector);
-}
-
-static inline void send_IPI_all(int vector)
-{
- __send_IPI_shortcut(APIC_DEST_ALLINC, vector);
-}
-
-void send_IPI_self(int vector)
-{
- __send_IPI_shortcut(APIC_DEST_SELF, vector);
-}
-
-static inline void send_IPI_mask(cpumask_t cpumask, int vector)
-{
- unsigned long mask = cpus_addr(cpumask)[0];
- unsigned long cfg;
- unsigned long flags;
-
- local_save_flags(flags);
- local_irq_disable();
-
- /*
- * Wait for idle.
- */
- apic_wait_icr_idle();
-
- /*
- * prepare target chip field
- */
- cfg = __prepare_ICR2(mask);
- apic_write_around(APIC_ICR2, cfg);
-
- /*
- * program the ICR
- */
- cfg = __prepare_ICR(0, vector);
-
- /*
- * Send the IPI. The write to APIC_ICR fires this off.
- */
- apic_write_around(APIC_ICR, cfg);
- local_irq_restore(flags);
-}