aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorAl Stone <ahs3@redhat.com>2013-11-09 17:07:58 -0700
committerGraeme Gregory <graeme.gregory@linaro.org>2013-11-19 10:30:35 +0000
commit4baf4a5ee33fb87d3713ad981cdd240c220c46b1 (patch)
tree081d6177a5e84aa670789df65cf8a8ca6f58171f
parenteb21dcbbf3048cc434b966ab97f19513107d4d28 (diff)
downloadleg-kernel-4baf4a5ee33fb87d3713ad981cdd240c220c46b1.tar.gz
ACPI: add clarifying comment about processor throttling in HW reduced mode
Signed-off-by: Al Stone <al.stone@linaro.org> Acked-by: Graeme Gregory <graeme.gregory@linaro.org>
-rw-r--r--drivers/acpi/processor_throttling.c8
1 files changed, 8 insertions, 0 deletions
diff --git a/drivers/acpi/processor_throttling.c b/drivers/acpi/processor_throttling.c
index e7dd2c1fee79..200738efaf81 100644
--- a/drivers/acpi/processor_throttling.c
+++ b/drivers/acpi/processor_throttling.c
@@ -942,6 +942,10 @@ static int acpi_processor_get_fadt_info(struct acpi_processor *pr)
return -EINVAL;
}
+ /*
+ * NB: in HW reduced mode, duty_width is always zero
+ * so this count may not be what is wanted.
+ */
pr->throttling.state_count = 1 << acpi_gbl_FADT.duty_width;
/*
@@ -991,6 +995,10 @@ static int acpi_processor_set_throttling_fadt(struct acpi_processor *pr,
/* Used to clear all duty_value bits */
duty_mask = pr->throttling.state_count - 1;
+ /*
+ * NB: in HW reduced mode, duty_offset is always zero
+ * so this mask may not be what is wanted.
+ */
duty_mask <<= acpi_gbl_FADT.duty_offset;
duty_mask = ~duty_mask;
}