[PATCH] Add support for type argument in PAL_GET_PSTATE

PAL_GET_PSTATE accepts a type argument to return different kinds of
frequency information.
Refer: Intel Itanium�Architecture Software Developer's Manual -
Volume 2: System Architecture, Revision 2.2
(http://developer.intel.com/design/itanium/manuals/245318.htm)

Add the support for type argument and use Instantaneous frequency
in the acpi driver.

Also fix a bug, where in return value of PAL_GET_PSTATE was getting compared
with 'control' bits instead of 'status' bits.

Signed-off-by: Venkatesh Pallipadi <[e-mail]>
Signed-off-by: Tony Luck <[e-mail]>

arch/ia64/kernel/cpufreq/acpi-cpufreq.c

···
 
 	dprintk("processor_get_pstate\n");
 
-	retval = ia64_pal_get_pstate(&pstate_index);
+	retval = ia64_pal_get_pstate(&pstate_index,
+	                             PAL_GET_PSTATE_TYPE_INSTANT);
 	*value = (u32) pstate_index;
 
 	if (retval)
···
 	dprintk("extract_clock\n");
 
 	for (i = 0; i < data->acpi_data.state_count; i++) {
-		if (value >= data->acpi_data.states[i].control)
+		if (value == data->acpi_data.states[i].status)
 			return data->acpi_data.states[i].core_frequency;
 	}
 	return data->acpi_data.states[i-1].core_frequency;
···
 		goto migrate_end;
 	}
 
-	/*
-	 * processor_get_pstate gets the average frequency since the
-	 * last get. So, do two PAL_get_freq()...
-	 */
-	ret = processor_get_pstate(&value);
+	/* processor_get_pstate gets the instantaneous frequency */
 	ret = processor_get_pstate(&value);
 
 	if (ret) {

include/asm-ia64/pal.h

···
 #define PAL_SET_PSTATE		263	/* set the P-state */
 #define PAL_BRAND_INFO		274	/* Processor branding information */
 
+#define PAL_GET_PSTATE_TYPE_LASTSET	0
+#define PAL_GET_PSTATE_TYPE_AVGANDRESET	1
+#define PAL_GET_PSTATE_TYPE_AVGNORESET	2
+#define PAL_GET_PSTATE_TYPE_INSTANT	3
+
 #ifndef __ASSEMBLY__
 
 #include <linux/types.h>
···
 
 /* Get the current P-state information */
 static inline s64
-ia64_pal_get_pstate (u64 *pstate_index)
+ia64_pal_get_pstate (u64 *pstate_index, unsigned long type)
 {
 	struct ia64_pal_retval iprv;
-	PAL_CALL_STK(iprv, PAL_GET_PSTATE, 0, 0, 0);
+	PAL_CALL_STK(iprv, PAL_GET_PSTATE, type, 0, 0);
 	*pstate_index = iprv.v0;
 	return iprv.status;
 }