* Copyright 2004 James Cleverdon, IBM.
* Subject to the GNU Public License, v.2
*
- * Flat APIC subarch code. Maximum 8 CPUs, logical delivery.
+ * Flat APIC subarch code.
*
* Hacked for x86-64 by James Cleverdon from i386 architecture code by
* Martin Bligh, Andi Kleen, James Bottomley, John Stultz, and
* James Cleverdon.
- * Ashok Raj <ashok.raj@intel.com>
- * Removed IPI broadcast shortcut to support CPU hotplug
*/
#include <linux/config.h>
#include <linux/threads.h>
#include <asm/smp.h>
#include <asm/ipi.h>
-/*
- * The following permit choosing broadcast IPI shortcut v.s sending IPI only
- * to online cpus via the send_IPI_mask varient.
- * The mask version is my preferred option, since it eliminates a lot of
- * other extra code that would need to be written to cleanup intrs sent
- * to a CPU while offline.
- *
- * Sending broadcast introduces lots of trouble in CPU hotplug situations.
- * These IPI's are delivered to cpu's irrespective of their offline status
- * and could pickup stale intr data when these CPUS are turned online.
- *
- * Not using broadcast is a cleaner approach IMO, but Andi Kleen disagrees with
- * the idea of not using broadcast IPI's anymore. Hence the run time check
- * is introduced, on his request so we can choose an alternate mechanism.
- *
- * Initial wacky performance tests that collect cycle counts show
- * no increase in using mask v.s broadcast version. In fact they seem
- * identical in terms of cycle counts.
- *
- * if we need to use broadcast, we need to do the following.
- *
- * cli;
- * hold call_lock;
- * clear any pending IPI, just ack and clear all pending intr
- * set cpu_online_map;
- * release call_lock;
- * sti;
- *
- * The complicated dummy irq processing shown above is not required if
- * we didnt sent IPI's to wrong CPU's in the first place.
- *
- * - Ashok Raj <ashok.raj@intel.com>
- */
-#ifdef CONFIG_HOTPLUG_CPU
-#define DEFAULT_SEND_IPI (1)
-#else
-#define DEFAULT_SEND_IPI (0)
-#endif
-
-static int no_broadcast=DEFAULT_SEND_IPI;
-
static cpumask_t flat_target_cpus(void)
{
return cpu_online_map;
num = smp_processor_id();
id = 1UL << num;
x86_cpu_to_log_apicid[num] = id;
- apic_write_around(APIC_DFR, APIC_DFR_FLAT);
+ apic_write(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);
+ apic_write(APIC_LDR, val);
}
static void flat_send_IPI_mask(cpumask_t cpumask, int vector)
* prepare target chip field
*/
cfg = __prepare_ICR2(mask);
- apic_write_around(APIC_ICR2, cfg);
+ apic_write(APIC_ICR2, cfg);
/*
* program the ICR
/*
* Send the IPI. The write to APIC_ICR fires this off.
*/
- apic_write_around(APIC_ICR, cfg);
+ apic_write(APIC_ICR, cfg);
local_irq_restore(flags);
}
-static inline void __local_flat_send_IPI_allbutself(int vector)
-{
- if (no_broadcast) {
- cpumask_t mask = cpu_online_map;
- int this_cpu = get_cpu();
-
- cpu_clear(this_cpu, mask);
- flat_send_IPI_mask(mask, vector);
- put_cpu();
- }
- else
- __send_IPI_shortcut(APIC_DEST_ALLBUT, vector, APIC_DEST_LOGICAL);
-}
-
-static inline void __local_flat_send_IPI_all(int vector)
-{
- if (no_broadcast)
- flat_send_IPI_mask(cpu_online_map, vector);
- else
- __send_IPI_shortcut(APIC_DEST_ALLINC, vector, APIC_DEST_LOGICAL);
-}
-
static void flat_send_IPI_allbutself(int vector)
{
+#ifndef CONFIG_HOTPLUG_CPU
if (((num_online_cpus()) - 1) >= 1)
- __local_flat_send_IPI_allbutself(vector);
+ __send_IPI_shortcut(APIC_DEST_ALLBUT, vector,APIC_DEST_LOGICAL);
+#else
+ cpumask_t allbutme = cpu_online_map;
+ int me = get_cpu(); /* Ensure we are not preempted when we clear */
+ cpu_clear(me, allbutme);
+
+ if (!cpus_empty(allbutme))
+ flat_send_IPI_mask(allbutme, vector);
+ put_cpu();
+#endif
}
static void flat_send_IPI_all(int vector)
{
- __local_flat_send_IPI_all(vector);
+ __send_IPI_shortcut(APIC_DEST_ALLINC, vector, APIC_DEST_LOGICAL);
}
static int flat_apic_id_registered(void)
return ((ebx >> 24) & 0xFF) >> index_msb;
}
-static __init int no_ipi_broadcast(char *str)
-{
- get_option(&str, &no_broadcast);
- printk ("Using %s mode\n", no_broadcast ? "No IPI Broadcast" :
- "IPI Broadcast");
- return 1;
-}
-
-__setup("no_ipi_broadcast", no_ipi_broadcast);
-
struct genapic apic_flat = {
.name = "flat",
.int_delivery_mode = dest_LowestPrio,
.phys_pkg_id = phys_pkg_id,
};
-static int __init print_ipi_mode(void)
+/*
+ * Physflat mode is used when there are more than 8 CPUs on a AMD system.
+ * We cannot use logical delivery in this case because the mask
+ * overflows, so use physical mode.
+ */
+
+static cpumask_t physflat_target_cpus(void)
{
- printk ("Using IPI %s mode\n", no_broadcast ? "No-Shortcut" :
- "Shortcut");
- return 0;
+ return cpumask_of_cpu(0);
}
-late_initcall(print_ipi_mode);
+static void physflat_send_IPI_mask(cpumask_t cpumask, int vector)
+{
+ send_IPI_mask_sequence(cpumask, vector);
+}
+
+static void physflat_send_IPI_allbutself(int vector)
+{
+ cpumask_t allbutme = cpu_online_map;
+ int me = get_cpu();
+ cpu_clear(me, allbutme);
+ physflat_send_IPI_mask(allbutme, vector);
+ put_cpu();
+}
+
+static void physflat_send_IPI_all(int vector)
+{
+ physflat_send_IPI_mask(cpu_online_map, vector);
+}
+
+static unsigned int physflat_cpu_mask_to_apicid(cpumask_t cpumask)
+{
+ int cpu;
+
+ /*
+ * We're using fixed IRQ delivery, can only return one phys APIC ID.
+ * May as well be the first.
+ */
+ cpu = first_cpu(cpumask);
+ if ((unsigned)cpu < NR_CPUS)
+ return x86_cpu_to_apicid[cpu];
+ else
+ return BAD_APICID;
+}
+
+struct genapic apic_physflat = {
+ .name = "physical flat",
+ .int_delivery_mode = dest_LowestPrio,
+ .int_dest_mode = (APIC_DEST_PHYSICAL != 0),
+ .int_delivery_dest = APIC_DEST_PHYSICAL | APIC_DM_LOWEST,
+ .target_cpus = physflat_target_cpus,
+ .apic_id_registered = flat_apic_id_registered,
+ .init_apic_ldr = flat_init_apic_ldr,/*not needed, but shouldn't hurt*/
+ .send_IPI_all = physflat_send_IPI_all,
+ .send_IPI_allbutself = physflat_send_IPI_allbutself,
+ .send_IPI_mask = physflat_send_IPI_mask,
+ .cpu_mask_to_apicid = physflat_cpu_mask_to_apicid,
+ .phys_pkg_id = phys_pkg_id,
+};
git.openpandora.org / pandora-kernel.git / blobdiff