diff options
Diffstat (limited to 'arch/x86_64/kernel/genapic_flat.c')
-rw-r--r-- | arch/x86_64/kernel/genapic_flat.c | 127 |
1 files changed, 127 insertions, 0 deletions
diff --git a/arch/x86_64/kernel/genapic_flat.c b/arch/x86_64/kernel/genapic_flat.c new file mode 100644 index 00000000000..b4cbbad0422 --- /dev/null +++ b/arch/x86_64/kernel/genapic_flat.c @@ -0,0 +1,127 @@ +/* + * Copyright 2004 James Cleverdon, IBM. + * Subject to the GNU Public License, v.2 + * + * Flat APIC subarch code. Maximum 8 CPUs, logical delivery. + * + * Hacked for x86-64 by James Cleverdon from i386 architecture code by + * Martin Bligh, Andi Kleen, James Bottomley, John Stultz, and + * James Cleverdon. + */ +#include <linux/config.h> +#include <linux/threads.h> +#include <linux/cpumask.h> +#include <linux/string.h> +#include <linux/kernel.h> +#include <linux/ctype.h> +#include <linux/init.h> +#include <asm/smp.h> +#include <asm/ipi.h> + + +static cpumask_t flat_target_cpus(void) +{ + return cpu_online_map; +} + +/* + * Set up the logical destination ID. + * + * Intel recommends to set DFR, LDR and TPR before enabling + * an APIC. See e.g. "AP-388 82489DX User's Manual" (Intel + * document number 292116). So here it goes... + */ +static void flat_init_apic_ldr(void) +{ + unsigned long val; + unsigned long num, id; + + num = smp_processor_id(); + id = 1UL << num; + x86_cpu_to_log_apicid[num] = id; + apic_write_around(APIC_DFR, APIC_DFR_FLAT); + val = apic_read(APIC_LDR) & ~APIC_LDR_MASK; + val |= SET_APIC_LOGICAL_ID(id); + apic_write_around(APIC_LDR, val); +} + +static void flat_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, APIC_DEST_LOGICAL); +} + +static void flat_send_IPI_all(int vector) +{ + __send_IPI_shortcut(APIC_DEST_ALLINC, vector, APIC_DEST_LOGICAL); +} + +static void flat_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, APIC_DEST_LOGICAL); + + /* + * Send the IPI. The write to APIC_ICR fires this off. + */ + apic_write_around(APIC_ICR, cfg); + local_irq_restore(flags); +} + +static int flat_apic_id_registered(void) +{ + return physid_isset(GET_APIC_ID(apic_read(APIC_ID)), phys_cpu_present_map); +} + +static unsigned int flat_cpu_mask_to_apicid(cpumask_t cpumask) +{ + return cpus_addr(cpumask)[0] & APIC_ALL_CPUS; +} + +static unsigned int phys_pkg_id(int index_msb) +{ + u32 ebx; + + ebx = cpuid_ebx(1); + return ((ebx >> 24) & 0xFF) >> index_msb; +} + +struct genapic apic_flat = { + .name = "flat", + .int_delivery_mode = dest_LowestPrio, + .int_dest_mode = (APIC_DEST_LOGICAL != 0), + .int_delivery_dest = APIC_DEST_LOGICAL | APIC_DM_LOWEST, + .target_cpus = flat_target_cpus, + .apic_id_registered = flat_apic_id_registered, + .init_apic_ldr = flat_init_apic_ldr, + .send_IPI_all = flat_send_IPI_all, + .send_IPI_allbutself = flat_send_IPI_allbutself, + .send_IPI_mask = flat_send_IPI_mask, + .cpu_mask_to_apicid = flat_cpu_mask_to_apicid, + .phys_pkg_id = phys_pkg_id, +}; |