powerpc/oprofile: G4 oprofile has variable number of counters

For ppc750 processors which use 4 performance counters instead of the
6 G4 uses but otherwise is compatible with G4.

Signed-off-by: Octavian Purdila <opurdila@ixiacom.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

1 files changed, 11 insertions, 10 deletions

diff --git a/arch/powerpc/oprofile/op_model_7450.c b/arch/powerpc/oprofile/op_model_7450.c
index cc599eb8768b..f8d36f940e88 100644
--- a/arch/powerpc/oprofile/op_model_7450.c
+++ b/arch/powerpc/oprofile/op_model_7450.c
@@ -29,7 +29,7 @@
 static unsigned long reset_value[OP_MAX_COUNTER];
 
 static int oprofile_running;
-static u32 mmcr0_val, mmcr1_val, mmcr2_val;
+static u32 mmcr0_val, mmcr1_val, mmcr2_val, num_pmcs;
 
 #define MMCR0_PMC1_SHIFT        6
 #define MMCR0_PMC2_SHIFT        0
@@ -88,13 +88,12 @@ static int fsl7450_cpu_setup(struct op_counter_config *ctr)
 
         mtspr(SPRN_MMCR0, mmcr0_val);
         mtspr(SPRN_MMCR1, mmcr1_val);
-        mtspr(SPRN_MMCR2, mmcr2_val);
+        if (num_pmcs > 4)
+                mtspr(SPRN_MMCR2, mmcr2_val);
 
         return 0;
 }
 
-#define NUM_CTRS 6
-
 /* Configures the global settings for the countes on all CPUs. */
 static int fsl7450_reg_setup(struct op_counter_config *ctr,
                              struct op_system_config *sys,
@@ -102,12 +101,13 @@ static int fsl7450_reg_setup(struct op_counter_config *ctr,
 {
         int i;
 
+        num_pmcs = num_ctrs;
         /* Our counters count up, and "count" refers to
          * how much before the next interrupt, and we interrupt
          * on overflow.  So we calculate the starting value
          * which will give us "count" until overflow.
          * Then we set the events on the enabled counters */
-        for (i = 0; i < NUM_CTRS; ++i)
+        for (i = 0; i < num_ctrs; ++i)
                 reset_value[i] = 0x80000000UL - ctr[i].count;
 
         /* Set events for Counters 1 & 2 */
@@ -123,9 +123,10 @@ static int fsl7450_reg_setup(struct op_counter_config *ctr,
 
         /* Set events for Counters 3-6 */
         mmcr1_val = mmcr1_event3(ctr[2].event)
-                | mmcr1_event4(ctr[3].event)
-                | mmcr1_event5(ctr[4].event)
-                | mmcr1_event6(ctr[5].event);
+                | mmcr1_event4(ctr[3].event);
+        if (num_ctrs > 4)
+                mmcr1_val |= mmcr1_event5(ctr[4].event)
+                        | mmcr1_event6(ctr[5].event);
 
         mmcr2_val = 0;
 
@@ -139,7 +140,7 @@ static int fsl7450_start(struct op_counter_config *ctr)
 
         mtmsr(mfmsr() | MSR_PMM);
 
-        for (i = 0; i < NUM_CTRS; ++i) {
+        for (i = 0; i < num_pmcs; ++i) {
                 if (ctr[i].enabled)
                         classic_ctr_write(i, reset_value[i]);
                 else
@@ -184,7 +185,7 @@ static void fsl7450_handle_interrupt(struct pt_regs *regs,
         pc = mfspr(SPRN_SIAR);
         is_kernel = is_kernel_addr(pc);
 
-        for (i = 0; i < NUM_CTRS; ++i) {
+        for (i = 0; i < num_pmcs; ++i) {
                 val = classic_ctr_read(i);
                 if (val < 0) {
                         if (oprofile_running && ctr[i].enabled) {