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Diffstat (limited to 'arch/x86/cpu/mp_init.c')
-rw-r--r--arch/x86/cpu/mp_init.c25
1 files changed, 19 insertions, 6 deletions
diff --git a/arch/x86/cpu/mp_init.c b/arch/x86/cpu/mp_init.c
index e77d7f2cd6..8b00d57c88 100644
--- a/arch/x86/cpu/mp_init.c
+++ b/arch/x86/cpu/mp_init.c
@@ -308,13 +308,26 @@ static int apic_wait_timeout(int total_delay, const char *msg)
return 0;
}
-static int start_aps(int ap_count, atomic_t *num_aps)
+/**
+ * start_aps() - Start up the APs and count how many we find
+ *
+ * This is called on the boot processor to start up all the other processors
+ * (here called APs).
+ *
+ * @num_aps: Number of APs we expect to find
+ * @ap_count: Initially zero. Incremented by this function for each AP found
+ * @return 0 if all APs were set up correctly or there are none to set up,
+ * -ENOSPC if the SIPI vector is too high in memory,
+ * -ETIMEDOUT if the ICR is busy or the second SIPI fails to complete
+ * -EIO if not all APs check in correctly
+ */
+static int start_aps(int num_aps, atomic_t *ap_count)
{
int sipi_vector;
/* Max location is 4KiB below 1MiB */
const int max_vector_loc = ((1 << 20) - (1 << 12)) >> 12;
- if (ap_count == 0)
+ if (num_aps == 0)
return 0;
/* The vector is sent as a 4k aligned address in one byte */
@@ -326,7 +339,7 @@ static int start_aps(int ap_count, atomic_t *num_aps)
return -ENOSPC;
}
- debug("Attempting to start %d APs\n", ap_count);
+ debug("Attempting to start %d APs\n", num_aps);
if (apic_wait_timeout(1000, "ICR not to be busy"))
return -ETIMEDOUT;
@@ -349,7 +362,7 @@ static int start_aps(int ap_count, atomic_t *num_aps)
return -ETIMEDOUT;
/* Wait for CPUs to check in up to 200 us */
- wait_for_aps(num_aps, ap_count, 200, 15);
+ wait_for_aps(ap_count, num_aps, 200, 15);
/* Send 2nd SIPI */
if (apic_wait_timeout(1000, "ICR not to be busy"))
@@ -362,9 +375,9 @@ static int start_aps(int ap_count, atomic_t *num_aps)
return -ETIMEDOUT;
/* Wait for CPUs to check in */
- if (wait_for_aps(num_aps, ap_count, 10000, 50)) {
+ if (wait_for_aps(ap_count, num_aps, 10000, 50)) {
debug("Not all APs checked in: %d/%d\n",
- atomic_read(num_aps), ap_count);
+ atomic_read(ap_count), num_aps);
return -EIO;
}