ACPI C4 support

Pavel Machek
2004-02-28T16:10:11Z

Hi!

Thomas told me:

>what about C4 - Cn states in the kernel implementation?
>A short look into the /proc/acpi/processor/.../power file let me think
>that only C0-C3 is supported by the kernel, even specification talks
>about Cn states?

As a first step, it would be nice if kernel at least used C0..C3 if
the machine supports them... This should do the trick. Does it look
okay?

Pavel

--- tmp/linux/drivers/acpi/processor.c 2004-02-20 12:29:21.000000000 +0100
+++ linux/drivers/acpi/processor.c 2004-02-28 15:30:52.000000000 +0100
@@ -2205,7 +2202,8 @@

if (!object.processor.pblk_address)
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No PBLK (NULL address)\n"));
- else if (object.processor.pblk_length != 6)
+ else if (object.processor.pblk_length < 6)
+ /* pblk_length of 7 is okay if cpu supports C4 */
ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid PBLK length [%d]\n",
object.processor.pblk_length));
else {

--
When do you have a heart between your knees?
[Johanka's followup: and *two* hearts?]