docs: pmu: Add Andes PMU node example

Add PMU node example for event index to counter index mapping
and selector value translation of Andes' CPUs.

Currently, there are 4 HPM counters that can be used to monitor
all of the events for each hart.

Signed-off-by: Yu Chien Peter Lin <peterlin@andestech.com>
Reviewed-by: Locus Wei-Han Chen <locus84@andestech.com>
Reviewed-by: Leo Yu-Chi Liang <ycliang@andestech.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
diff --git a/docs/pmu_support.md b/docs/pmu_support.md
index 8cfa08c..9b48f1e 100644
--- a/docs/pmu_support.md
+++ b/docs/pmu_support.md
@@ -125,3 +125,85 @@
 					  <0x0 0x2 0xffffffff 0xffffe0ff 0x18>;
 };
 ```
+
+### Example 3
+
+```
+/*
+ * For Andes 45-series platforms. The encodings can be found in the
+ * "Machine Performance Monitoring Event Selector" section
+ * http://www.andestech.com/wp-content/uploads/AX45MP-1C-Rev.-5.0.0-Datasheet.pdf
+ */
+pmu {
+	compatible 			= "riscv,pmu";
+	riscv,event-to-mhpmevent =
+					 <0x1 0x0000 0x10>, /* CPU_CYCLES          -> Cycle count */
+					 <0x2 0x0000 0x20>, /* INSTRUCTIONS        -> Retired instruction count */
+					 <0x3 0x0000 0x41>, /* CACHE_REFERENCES    -> D-Cache access */
+					 <0x4 0x0000 0x51>, /* CACHE_MISSES        -> D-Cache miss */
+					 <0x5 0x0000 0x80>, /* BRANCH_INSTRUCTIONS -> Conditional branch instruction count */
+					 <0x6 0x0000 0x02>, /* BRANCH_MISSES       -> Misprediction of conditional branches */
+					 <0x10000 0x0000 0x61>,  /* L1D_READ_ACCESS  -> D-Cache load access */
+					 <0x10001 0x0000 0x71>,  /* L1D_READ_MISS    -> D-Cache load miss */
+					 <0x10002 0x0000 0x81>,  /* L1D_WRITE_ACCESS -> D-Cache store access */
+					 <0x10003 0x0000 0x91>,  /* L1D_WRITE_MISS   -> D-Cache store miss */
+					 <0x10008 0x0000 0x21>,  /* L1I_READ_ACCESS  -> I-Cache access */
+					 <0x10009 0x0000 0x31>;  /* L1I_READ_MISS    -> I-Cache miss */
+	riscv,event-to-mhpmcounters = <0x1 0x6 0x78>,
+							<0x10000 0x10003 0x78>,
+							<0x10008 0x10009 0x78>;
+	riscv,raw-event-to-mhpmcounters =
+						<0x0 0x10 0xffffffff 0xffffffff 0x78>, /* Cycle count */
+						<0x0 0x20 0xffffffff 0xffffffff 0x78>, /* Retired instruction count */
+						<0x0 0x30 0xffffffff 0xffffffff 0x78>, /* Integer load instruction count */
+						<0x0 0x40 0xffffffff 0xffffffff 0x78>, /* Integer store instruction count */
+						<0x0 0x50 0xffffffff 0xffffffff 0x78>, /* Atomic instruction count */
+						<0x0 0x60 0xffffffff 0xffffffff 0x78>, /* System instruction count */
+						<0x0 0x70 0xffffffff 0xffffffff 0x78>, /* Integer computational instruction count */
+						<0x0 0x80 0xffffffff 0xffffffff 0x78>, /* Conditional branch instruction count */
+						<0x0 0x90 0xffffffff 0xffffffff 0x78>, /* Taken conditional branch instruction count */
+						<0x0 0xA0 0xffffffff 0xffffffff 0x78>, /* JAL instruction count */
+						<0x0 0xB0 0xffffffff 0xffffffff 0x78>, /* JALR instruction count */
+						<0x0 0xC0 0xffffffff 0xffffffff 0x78>, /* Return instruction count */
+						<0x0 0xD0 0xffffffff 0xffffffff 0x78>, /* Control transfer instruction count */
+						<0x0 0xE0 0xffffffff 0xffffffff 0x78>, /* EXEC.IT instruction count */
+						<0x0 0xF0 0xffffffff 0xffffffff 0x78>, /* Integer multiplication instruction count */
+						<0x0 0x100 0xffffffff 0xffffffff 0x78>, /* Integer division instruction count */
+						<0x0 0x110 0xffffffff 0xffffffff 0x78>, /* Floating-point load instruction count */
+						<0x0 0x120 0xffffffff 0xffffffff 0x78>, /* Floating-point store instruction count */
+						<0x0 0x130 0xffffffff 0xffffffff 0x78>, /* Floating-point addition/subtraction instruction count */
+						<0x0 0x140 0xffffffff 0xffffffff 0x78>, /* Floating-point multiplication instruction count */
+						<0x0 0x150 0xffffffff 0xffffffff 0x78>, /* Floating-point fused multiply-add instruction count */
+						<0x0 0x160 0xffffffff 0xffffffff 0x78>, /* Floating-point division or square-root instruction count */
+						<0x0 0x170 0xffffffff 0xffffffff 0x78>, /* Other floating-point instruction count */
+						<0x0 0x180 0xffffffff 0xffffffff 0x78>, /* Integer multiplication and add/sub instruction count */
+						<0x0 0x190 0xffffffff 0xffffffff 0x78>, /* Retired operation count */
+						<0x0 0x01 0xffffffff 0xffffffff 0x78>, /* ILM access */
+						<0x0 0x11 0xffffffff 0xffffffff 0x78>, /* DLM access */
+						<0x0 0x21 0xffffffff 0xffffffff 0x78>, /* I-Cache access */
+						<0x0 0x31 0xffffffff 0xffffffff 0x78>, /* I-Cache miss */
+						<0x0 0x41 0xffffffff 0xffffffff 0x78>, /* D-Cache access */
+						<0x0 0x51 0xffffffff 0xffffffff 0x78>, /* D-Cache miss */
+						<0x0 0x61 0xffffffff 0xffffffff 0x78>, /* D-Cache load access */
+						<0x0 0x71 0xffffffff 0xffffffff 0x78>, /* D-Cache load miss */
+						<0x0 0x81 0xffffffff 0xffffffff 0x78>, /* D-Cache store access */
+						<0x0 0x91 0xffffffff 0xffffffff 0x78>, /* D-Cache store miss */
+						<0x0 0xA1 0xffffffff 0xffffffff 0x78>, /* D-Cache writeback */
+						<0x0 0xB1 0xffffffff 0xffffffff 0x78>, /* Cycles waiting for I-Cache fill data */
+						<0x0 0xC1 0xffffffff 0xffffffff 0x78>, /* Cycles waiting for D-Cache fill data */
+						<0x0 0xD1 0xffffffff 0xffffffff 0x78>, /* Uncached fetch data access from bus */
+						<0x0 0xE1 0xffffffff 0xffffffff 0x78>, /* Uncached load data access from bus */
+						<0x0 0xF1 0xffffffff 0xffffffff 0x78>, /* Cycles waiting for uncached fetch data from bus */
+						<0x0 0x101 0xffffffff 0xffffffff 0x78>, /* Cycles waiting for uncached load data from bus */
+						<0x0 0x111 0xffffffff 0xffffffff 0x78>, /* Main ITLB access */
+						<0x0 0x121 0xffffffff 0xffffffff 0x78>, /* Main ITLB miss */
+						<0x0 0x131 0xffffffff 0xffffffff 0x78>, /* Main DTLB access */
+						<0x0 0x141 0xffffffff 0xffffffff 0x78>, /* Main DTLB miss */
+						<0x0 0x151 0xffffffff 0xffffffff 0x78>, /* Cycles waiting for Main ITLB fill data */
+						<0x0 0x161 0xffffffff 0xffffffff 0x78>, /* Pipeline stall cycles caused by Main DTLB miss */
+						<0x0 0x171 0xffffffff 0xffffffff 0x78>, /* Hardware prefetch bus access */
+						<0x0 0x02 0xffffffff 0xffffffff 0x78>, /* Misprediction of conditional branches */
+						<0x0 0x12 0xffffffff 0xffffffff 0x78>, /* Misprediction of taken conditional branches */
+						<0x0 0x22 0xffffffff 0xffffffff 0x78>; /* Misprediction of targets of Return instructions */
+};
+```