[Cbe-oss-dev] [PATCH] OProfile: fix cbe pm signal routing problem

[Bob Nelson]

Fix debug_bus_control and group_control PMU register values set up in
set_pm_event().  Initialize variables before calling set_pm_event().
Delete unused static array and code that initialized it.
Rename constant to better reflect usage.

Signed-off-by: Bob Nelson <rrnelson at us.ibm.com>

---

This is a revised version of a patch initially submitted by Takashi Yamamoto
(Takashi02_Yamamoto at hq.scei.sony.co.jp).
After investigating the code in more depth I agree with Yamamoto-san's fix.
In the process I also found another potential problem and some code that
could use some cleanup.  The whole module could still use some more work but
that will have to wait for now.

Index: linux-2.6.22/arch/powerpc/oprofile/op_model_cell.c
===================================================================
--- linux-2.6.22.orig/arch/powerpc/oprofile/op_model_cell.c
+++ linux-2.6.22/arch/powerpc/oprofile/op_model_cell.c
@@ -61,7 +61,7 @@ static unsigned int spu_cycle_reset = 0;
 #define NUM_THREADS 2         /* number of physical threads in
 			       * physical processor
 			       */
-#define NUM_TRACE_BUS_WORDS 4
+#define NUM_DEBUG_BUS_WORDS 4
 #define NUM_INPUT_BUS_WORDS 2
 
 #define MAX_SPU_COUNT 0xFFFFFF	/* maximum 24 bit LFSR value */
@@ -169,7 +169,6 @@ static DEFINE_SPINLOCK(virt_cntr_lock);
 
 static u32 ctr_enabled;
 
-static unsigned char trace_bus[NUM_TRACE_BUS_WORDS];
 static unsigned char input_bus[NUM_INPUT_BUS_WORDS];
 
 /*
@@ -298,7 +297,7 @@ static void set_pm_event(u32 ctr, int ev
 
 	p->signal_group = event / 100;
 	p->bus_word = bus_word;
-	p->sub_unit = (unit_mask & 0x0000f000) >> 12;
+	p->sub_unit = GET_SUB_UNIT(unit_mask);
 
 	pm_regs.pm07_cntrl[ctr] = 0;
 	pm_regs.pm07_cntrl[ctr] |= PM07_CTR_COUNT_CYCLES(count_cycles);
@@ -334,16 +333,16 @@ static void set_pm_event(u32 ctr, int ev
 		p->bit = signal_bit;
 	}
 
-	for (i = 0; i < NUM_TRACE_BUS_WORDS; i++) {
+	for (i = 0; i < NUM_DEBUG_BUS_WORDS; i++) {
 		if (bus_word & (1 << i)) {
 			pm_regs.debug_bus_control |=
-			    (bus_type << (31 - (2 * i) + 1));
+			    (bus_type << (30 - (2 * i)));
 
 			for (j = 0; j < NUM_INPUT_BUS_WORDS; j++) {
 				if (input_bus[j] == 0xff) {
 					input_bus[j] = i;
 					pm_regs.group_control |=
-					    (i << (31 - i));
+					    (i << (30 - (2 * j)));
 
 					break;
 				}
@@ -450,6 +449,12 @@ static void cell_virtual_cntr(unsigned l
 	hdw_thread = 1 ^ hdw_thread;
 	next_hdw_thread = hdw_thread;
 
+	pm_regs.group_control = 0;
+	pm_regs.debug_bus_control = 0;
+
+	for (i = 0; i < NUM_INPUT_BUS_WORDS; i++)
+		input_bus[i] = 0xff;
+
 	/*
 	 * There are some per thread events.  Must do the
 	 * set event, for the thread that is being started
@@ -619,9 +624,6 @@ static int cell_reg_setup(struct op_coun
 		pmc_cntrl[1][i].vcntr = i;
 	}
 
-	for (i = 0; i < NUM_TRACE_BUS_WORDS; i++)
-		trace_bus[i] = 0xff;
-
 	for (i = 0; i < NUM_INPUT_BUS_WORDS; i++)
 		input_bus[i] = 0xff;