[POWERPC] cell: PPU Oprofile cleanup patch

This is a clean up patch that includes the following changes:

 -Some comments were added to clarify the code based on feedback
  from the community.
 -The write_pm_cntrl() and set_count_mode() were passed a
  structure element from a global variable.  The argument was
  removed so the functions now just operate on the global directly.
 -The set_pm_event() function call in the cell_virtual_cntr()
  routine was moved to a for-loop before the for_each_cpu loop

Signed-off-by: Carl Love <carll@us.ibm.com>
Signed-off-by: Maynard Johnson <mpjohn@us.ibm.com>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>

2 files changed, 67 insertions, 51 deletions

diff --git a/arch/powerpc/oprofile/op_model_cell.c b/arch/powerpc/oprofile/op_model_cell.c
index 2eb15f388103..8d4a9586464d 100644
--- a/arch/powerpc/oprofile/op_model_cell.c
+++ b/arch/powerpc/oprofile/op_model_cell.c
@@ -41,8 +41,12 @@
 #define PPU_CYCLES_EVENT_NUM 1  /*  event number for CYCLES */
 #define CBE_COUNT_ALL_CYCLES 0x42800000 /* PPU cycle event specifier */
 
-#define NUM_THREADS 2
-#define VIRT_CNTR_SW_TIME_NS 100000000  // 0.5 seconds
+#define NUM_THREADS 2         /* number of physical threads in
+                               * physical processor
+                               */
+#define NUM_TRACE_BUS_WORDS 4
+#define NUM_INPUT_BUS_WORDS 2
+
 
 struct pmc_cntrl_data {
         unsigned long vcntr;
@@ -93,7 +97,6 @@ static struct {
         u32 pm07_cntrl[NR_PHYS_CTRS];
 } pm_regs;
 
-
 #define GET_SUB_UNIT(x) ((x & 0x0000f000) >> 12)
 #define GET_BUS_WORD(x) ((x & 0x000000f0) >> 4)
 #define GET_BUS_TYPE(x) ((x & 0x00000300) >> 8)
@@ -101,7 +104,6 @@ static struct {
 #define GET_COUNT_CYCLES(x) (x & 0x00000001)
 #define GET_INPUT_CONTROL(x) ((x & 0x00000004) >> 2)
 
-
 static DEFINE_PER_CPU(unsigned long[NR_PHYS_CTRS], pmc_values);
 
 static struct pmc_cntrl_data pmc_cntrl[NUM_THREADS][NR_PHYS_CTRS];
@@ -129,8 +131,8 @@ static spinlock_t virt_cntr_lock = SPIN_LOCK_UNLOCKED;
 
 static u32 ctr_enabled;
 
-static unsigned char trace_bus[4];
-static unsigned char input_bus[2];
+static unsigned char trace_bus[NUM_TRACE_BUS_WORDS];
+static unsigned char input_bus[NUM_INPUT_BUS_WORDS];
 
 /*
  * Firmware interface functions
@@ -183,7 +185,8 @@ static void pm_rtas_activate_signals(u32 node, u32 count)
         for (j = 0; j < count; j++) {
                 /* fw expects physical cpu # */
                 pm_signal_local[j].cpu = node;
-                pm_signal_local[j].signal_group = pm_signal[j].signal_group;
+                pm_signal_local[j].signal_group
+                        = pm_signal[j].signal_group;
                 pm_signal_local[j].bus_word = pm_signal[j].bus_word;
                 pm_signal_local[j].sub_unit = pm_signal[j].sub_unit;
                 pm_signal_local[j].bit = pm_signal[j].bit;
@@ -232,13 +235,21 @@ static void set_pm_event(u32 ctr, int event, u32 unit_mask)
 
         p->signal_group = event / 100;
         p->bus_word = bus_word;
-        p->sub_unit = unit_mask & 0x0000f000;
+        p->sub_unit = (unit_mask & 0x0000f000) >> 12;
 
         pm_regs.pm07_cntrl[ctr] = 0;
         pm_regs.pm07_cntrl[ctr] |= PM07_CTR_COUNT_CYCLES(count_cycles);
         pm_regs.pm07_cntrl[ctr] |= PM07_CTR_POLARITY(polarity);
         pm_regs.pm07_cntrl[ctr] |= PM07_CTR_INPUT_CONTROL(input_control);
 
+        /* Some of the islands signal selection is based on 64 bit words.
+         * The debug bus words are 32 bits, the input words to the performance
+         * counters are defined as 32 bits.  Need to convert the 64 bit island
+         * specification to the appropriate 32 input bit and bus word for the
+         * performance counter event selection.  See the CELL Performance
+         * monitoring signals manual and the Perf cntr hardware descriptions
+         * for the details.
+         */
         if (input_control == 0) {
                 if (signal_bit > 31) {
                         signal_bit -= 32;
@@ -259,12 +270,12 @@ static void set_pm_event(u32 ctr, int event, u32 unit_mask)
                 p->bit = signal_bit;
         }
 
-        for (i = 0; i < 4; i++) {
+        for (i = 0; i < NUM_TRACE_BUS_WORDS; i++) {
                 if (bus_word & (1 << i)) {
                         pm_regs.debug_bus_control |=
                             (bus_type << (31 - (2 * i) + 1));
 
-                        for (j = 0; j < 2; j++) {
+                        for (j = 0; j < NUM_INPUT_BUS_WORDS; j++) {
                                 if (input_bus[j] == 0xff) {
                                         input_bus[j] = i;
                                         pm_regs.group_control |=
@@ -278,52 +289,58 @@ out:
         ;
 }
 
-static void write_pm_cntrl(int cpu, struct pm_cntrl *pm_cntrl)
+static void write_pm_cntrl(int cpu)
 {
-        /* Oprofile will use 32 bit counters, set bits 7:10 to 0 */
+        /* Oprofile will use 32 bit counters, set bits 7:10 to 0
+         * pmregs.pm_cntrl is a global
+         */
+
         u32 val = 0;
-        if (pm_cntrl->enable == 1)
+        if (pm_regs.pm_cntrl.enable == 1)
                 val |= CBE_PM_ENABLE_PERF_MON;
 
-        if (pm_cntrl->stop_at_max == 1)
+        if (pm_regs.pm_cntrl.stop_at_max == 1)
                 val |= CBE_PM_STOP_AT_MAX;
 
-        if (pm_cntrl->trace_mode == 1)
-                val |= CBE_PM_TRACE_MODE_SET(pm_cntrl->trace_mode);
+        if (pm_regs.pm_cntrl.trace_mode == 1)
+                val |= CBE_PM_TRACE_MODE_SET(pm_regs.pm_cntrl.trace_mode);
 
-        if (pm_cntrl->freeze == 1)
+        if (pm_regs.pm_cntrl.freeze == 1)
                 val |= CBE_PM_FREEZE_ALL_CTRS;
 
         /* Routine set_count_mode must be called previously to set
          * the count mode based on the user selection of user and kernel.
          */
-        val |= CBE_PM_COUNT_MODE_SET(pm_cntrl->count_mode);
+        val |= CBE_PM_COUNT_MODE_SET(pm_regs.pm_cntrl.count_mode);
         cbe_write_pm(cpu, pm_control, val);
 }
 
 static inline void
-set_count_mode(u32 kernel, u32 user, struct pm_cntrl *pm_cntrl)
+set_count_mode(u32 kernel, u32 user)
 {
         /* The user must specify user and kernel if they want them. If
-         *  neither is specified, OProfile will count in hypervisor mode
+         *  neither is specified, OProfile will count in hypervisor mode.
+         *  pm_regs.pm_cntrl is a global
          */
         if (kernel) {
                 if (user)
-                        pm_cntrl->count_mode = CBE_COUNT_ALL_MODES;
+                        pm_regs.pm_cntrl.count_mode = CBE_COUNT_ALL_MODES;
                 else
-                        pm_cntrl->count_mode = CBE_COUNT_SUPERVISOR_MODE;
+                        pm_regs.pm_cntrl.count_mode =
+                                CBE_COUNT_SUPERVISOR_MODE;
         } else {
                 if (user)
-                        pm_cntrl->count_mode = CBE_COUNT_PROBLEM_MODE;
+                        pm_regs.pm_cntrl.count_mode = CBE_COUNT_PROBLEM_MODE;
                 else
-                        pm_cntrl->count_mode = CBE_COUNT_HYPERVISOR_MODE;
+                        pm_regs.pm_cntrl.count_mode =
+                                CBE_COUNT_HYPERVISOR_MODE;
         }
 }
 
 static inline void enable_ctr(u32 cpu, u32 ctr, u32 * pm07_cntrl)
 {
 
-        pm07_cntrl[ctr] |= PM07_CTR_ENABLE(1);
+        pm07_cntrl[ctr] |= CBE_PM_CTR_ENABLE;
         cbe_write_pm07_control(cpu, ctr, pm07_cntrl[ctr]);
 }
 
@@ -365,6 +382,14 @@ static void cell_virtual_cntr(unsigned long data)
         hdw_thread = 1 ^ hdw_thread;
         next_hdw_thread = hdw_thread;
 
+        for (i = 0; i < num_counters; i++)
+        /* There are some per thread events.  Must do the
+         * set event, for the thread that is being started
+         */
+                set_pm_event(i,
+                        pmc_cntrl[next_hdw_thread][i].evnts,
+                        pmc_cntrl[next_hdw_thread][i].masks);
+
         /* The following is done only once per each node, but
          * we need cpu #, not node #, to pass to the cbe_xxx functions.
          */
@@ -385,12 +410,13 @@ static void cell_virtual_cntr(unsigned long data)
                             == 0xFFFFFFFF)
                                 /* If the cntr value is 0xffffffff, we must
                                  * reset that to 0xfffffff0 when the current
-                                 * thread is restarted.  This will generate a new
-                                 * interrupt and make sure that we never restore
-                                 * the counters to the max value.  If the counters
-                                 * were restored to the max value, they do not
-                                 * increment and no interrupts are generated.  Hence
-                                 * no more samples will be collected on that cpu.
+                                 * thread is restarted.  This will generate a
+                                 * new interrupt and make sure that we never
+                                 * restore the counters to the max value.  If
+                                 * the counters were restored to the max value,
+                                 * they do not increment and no interrupts are
+                                 * generated.  Hence no more samples will be
+                                 * collected on that cpu.
                                  */
                                 cbe_write_ctr(cpu, i, 0xFFFFFFF0);
                         else
@@ -410,9 +436,6 @@ static void cell_virtual_cntr(unsigned long data)
                                  * Must do the set event, enable_cntr
                                  * for each cpu.
                                  */
-                                set_pm_event(i,
-                                     pmc_cntrl[next_hdw_thread][i].evnts,
-                                     pmc_cntrl[next_hdw_thread][i].masks);
                                 enable_ctr(cpu, i,
                                            pm_regs.pm07_cntrl);
                         } else {
@@ -465,8 +488,7 @@ cell_reg_setup(struct op_counter_config *ctr,
         pm_regs.pm_cntrl.trace_mode = 0;
         pm_regs.pm_cntrl.freeze = 1;
 
-        set_count_mode(sys->enable_kernel, sys->enable_user,
-                       &pm_regs.pm_cntrl);
+        set_count_mode(sys->enable_kernel, sys->enable_user);
 
         /* Setup the thread 0 events */
         for (i = 0; i < num_ctrs; ++i) {
@@ -498,10 +520,10 @@ cell_reg_setup(struct op_counter_config *ctr,
                 pmc_cntrl[1][i].vcntr = i;
         }
 
-        for (i = 0; i < 4; i++)
+        for (i = 0; i < NUM_TRACE_BUS_WORDS; i++)
                 trace_bus[i] = 0xff;
 
-        for (i = 0; i < 2; i++)
+        for (i = 0; i < NUM_INPUT_BUS_WORDS; i++)
                 input_bus[i] = 0xff;
 
         /* Our counters count up, and "count" refers to
@@ -560,7 +582,7 @@ static void cell_cpu_setup(struct op_counter_config *cntr)
         cbe_write_pm(cpu, pm_start_stop, 0);
         cbe_write_pm(cpu, group_control, pm_regs.group_control);
         cbe_write_pm(cpu, debug_bus_control, pm_regs.debug_bus_control);
-        write_pm_cntrl(cpu, &pm_regs.pm_cntrl);
+        write_pm_cntrl(cpu);
 
         for (i = 0; i < num_counters; ++i) {
                 if (ctr_enabled & (1 << i)) {
@@ -602,7 +624,7 @@ static void cell_global_start(struct op_counter_config *ctr)
                         }
                 }
 
-                cbe_clear_pm_interrupts(cpu);
+                cbe_get_and_clear_pm_interrupts(cpu);
                 cbe_enable_pm_interrupts(cpu, hdw_thread, interrupt_mask);
                 cbe_enable_pm(cpu);
         }
@@ -672,7 +694,7 @@ cell_handle_interrupt(struct pt_regs *regs, struct op_counter_config *ctr)
 
         cbe_disable_pm(cpu);
 
-        interrupt_mask = cbe_clear_pm_interrupts(cpu);
+        interrupt_mask = cbe_get_and_clear_pm_interrupts(cpu);
 
         /* If the interrupt mask has been cleared, then the virt cntr
          * has cleared the interrupt.  When the thread that generated
diff --git a/arch/powerpc/platforms/cell/pmu.c b/arch/powerpc/platforms/cell/pmu.c
index d04ae1671e6c..66ca4b5a1dbc 100644
--- a/arch/powerpc/platforms/cell/pmu.c
+++ b/arch/powerpc/platforms/cell/pmu.c
@@ -345,18 +345,12 @@ EXPORT_SYMBOL_GPL(cbe_read_trace_buffer);
  * Enabling/disabling interrupts for the entire performance monitoring unit.
  */
 
-u32 cbe_query_pm_interrupts(u32 cpu)
-{
-        return cbe_read_pm(cpu, pm_status);
-}
-EXPORT_SYMBOL_GPL(cbe_query_pm_interrupts);
-
-u32 cbe_clear_pm_interrupts(u32 cpu)
+u32 cbe_get_and_clear_pm_interrupts(u32 cpu)
 {
         /* Reading pm_status clears the interrupt bits. */
-        return cbe_query_pm_interrupts(cpu);
+        return cbe_read_pm(cpu, pm_status);
 }
-EXPORT_SYMBOL_GPL(cbe_clear_pm_interrupts);
+EXPORT_SYMBOL_GPL(cbe_get_and_clear_pm_interrupts);
 
 void cbe_enable_pm_interrupts(u32 cpu, u32 thread, u32 mask)
 {
@@ -371,7 +365,7 @@ EXPORT_SYMBOL_GPL(cbe_enable_pm_interrupts);
 
 void cbe_disable_pm_interrupts(u32 cpu)
 {
-        cbe_clear_pm_interrupts(cpu);
+        cbe_get_and_clear_pm_interrupts(cpu);
         cbe_write_pm(cpu, pm_status, 0);
 }
 EXPORT_SYMBOL_GPL(cbe_disable_pm_interrupts);