On 05/18/2016 12:07 PM, Gautham R Shenoy wrote:

Hi Shreyas,

On Tue, May 03, 2016 at 01:54:33PM +0530, Shreyas B. Prabhu wrote:

quoted

power7_powersave_common does common steps needed before entering idle
state and eventually changes MSR to MSR_IDLE and does rfid to
power7_enter_nap_mode.

Make it more generic by passing the rfid address as a function parameter.
Also make function name more generic.

[..snip..]

quoted

 _GLOBAL(power7_winkle)
-	li	r3,3
+	li	r3,PNV_THREAD_WINKLE

This particular change above can go as an independent patch.

Okay.

quoted

 _GLOBAL(power7_wakeup_tb_loss)

diff --git a/arch/powerpc/kernel/idle_power_common.S b/arch/powerpc/kernel/idle_power_common.S
index 05954ae..ff7a541 100644
--- a/arch/powerpc/kernel/idle_power_common.S
+++ b/arch/powerpc/kernel/idle_power_common.S

@@ -21,8 +21,10 @@
  * To check IRQ_HAPPENED in r4
  * 	0 - don't check
  * 	1 - check
+ *
+ * Address to 'rfid' to in r5
  */
-_GLOBAL(power7_powersave_common)
+_GLOBAL(power_powersave_common)
 	/* Use r3 to pass state nap/sleep/winkle */
 	/* NAP is a state loss, we create a regs frame on the
 	 * stack, fill it up with the state we care about and

@@ -79,13 +81,12 @@ _GLOBAL(power7_powersave_common)
 	 * because as soon as we do that, another thread can switch
 	 * the MMU context to the guest.
 	 */
-	LOAD_REG_IMMEDIATE(r5, MSR_IDLE)
+	LOAD_REG_IMMEDIATE(r7, MSR_IDLE)
 	li	r6, MSR_RI
 	andc	r6, r9, r6
-	LOAD_REG_ADDR(r7, power7_enter_nap_mode)
 	mtmsrd	r6, 1		/* clear RI before setting SRR0/1 */
-	mtspr	SPRN_SRR0, r7
-	mtspr	SPRN_SRR1, r5
+	mtspr	SPRN_SRR0, r5
+	mtspr	SPRN_SRR1, r7
 	rfid
 	/* No return */

Any particular reason why you swapped the roles of r5 and r7 ?

With this patch, r5 which is the third parameter to
power_powersave_common contains the return address that needs to be
written to SRR0. So here I'm keeping r5 unaltered and using r7 for the MSR.

Thanks,
Shreyas