diff options
| author | Simon Glass <sjg@chromium.org> | 2020-07-17 08:48:10 -0600 |
|---|---|---|
| committer | Bin Meng <bmeng.cn@gmail.com> | 2020-07-20 09:46:43 +0800 |
| commit | 3a5752ccff5a8ee2952d0d81387f32825b73756e (patch) | |
| tree | 219291416c9cdd3a17c246d782b9a5a07625eec6 | |
| parent | e624858407039ffeb4e4007bb2677d8e4fa6536c (diff) | |
x86: mp_init: Switch parameter names in start_aps()
These parameters are named differently from elsewhere in this file. Switch
them to avoid confusion.
Also add comments to this function.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Wolfgang Wallner <wolfgang.wallner@br-automation.com>
| -rw-r--r-- | arch/x86/cpu/mp_init.c | 25 |
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; } |