snRuntime: Various improvements from offload study

pulp-platform · Sep 11, 2023 · 5bd34b1 · 5bd34b1
1 parent 8c5cf9e
commit 5bd34b1
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Showing 8 changed files with 69 additions and 39 deletions.
diff --git a/sw/snRuntime/api/cluster_interrupt_decls.h b/sw/snRuntime/api/cluster_interrupt_decls.h
@@ -6,6 +6,8 @@ inline void snrt_int_cluster_set(uint32_t mask);
 
 inline void snrt_int_cluster_clr(uint32_t mask);
 
+inline void snrt_int_clr_mcip_unsafe();
+
 inline void snrt_int_clr_mcip();
 
 inline void snrt_int_set_mcip();
diff --git a/sw/snRuntime/src/cluster_interrupts.h b/sw/snRuntime/src/cluster_interrupts.h
@@ -2,6 +2,8 @@
 // Licensed under the Apache License, Version 2.0, see LICENSE for details.
 // SPDX-License-Identifier: Apache-2.0
 
+#include "../../deps/riscv-opcodes/encoding.h"
+
 /**
  * @brief Write mask to the cluster-local interrupt set register
  * @param mask set bit at X sets the interrupt of hart X
@@ -18,10 +20,33 @@ inline void snrt_int_cluster_clr(uint32_t mask) {
     *(snrt_cluster_clint_clr_ptr()) = mask;
 }
 
-inline void snrt_int_clr_mcip() {
+/**
+ * @brief Clear MCIP interrupt
+ * @detail The interrupt is cleared asynchronously, i.e. it may not be cleared
+ *         yet when the function returns. Use `snrt_int_clr_mcip()` or
+ *         `snrt_int_wait_mcip_clr` if you need to block until the interrupt is
+ *         cleared.
+ */
+inline void snrt_int_clr_mcip_unsafe() {
     snrt_int_cluster_clr(1 << snrt_cluster_core_idx());
 }
 
+/**
+ * @brief Wait for MCIP interrupt to be cleared
+ */
+inline void snrt_int_wait_mcip_clr() {
+    while (read_csr(mip) & MIP_MCIP)
+        ;
+}
+
+/**
+ * @brief Clear MCIP interrupt and wait for the write to have effect
+ */
+inline void snrt_int_clr_mcip() {
+    snrt_int_clr_mcip_unsafe();
+    snrt_int_wait_mcip_clr();
+}
+
 inline void snrt_int_set_mcip() {
     snrt_int_cluster_set(1 << snrt_cluster_core_idx());
 }
diff --git a/sw/snRuntime/src/riscv.h b/sw/snRuntime/src/riscv.h
@@ -10,6 +10,8 @@
  */
 static inline void snrt_wfi() { asm volatile("wfi"); }
 
+static inline void snrt_nop() { asm volatile("nop" : : :); }
+
 static inline uint32_t snrt_mcycle() {
     uint32_t register r;
     asm volatile("csrr %0, mcycle" : "=r"(r) : : "memory");

diff --git a/sw/snRuntime/src/start.c b/sw/snRuntime/src/start.c
@@ -2,13 +2,6 @@
 // Licensed under the Apache License, Version 2.0, see LICENSE for details.
 // SPDX-License-Identifier: Apache-2.0
 
-static inline void snrt_crt0_cluster_hw_barrier() {
-    uint32_t register r;
-    uint32_t hw_barrier =
-        SNRT_CLUSTER_HW_BARRIER_ADDR + snrt_cluster_idx() * SNRT_CLUSTER_OFFSET;
-    asm volatile("lw %0, 0(%1)" : "=r"(r) : "r"(hw_barrier) : "memory");
-}
-
 #ifdef SNRT_INIT_CLS
 static inline uint32_t snrt_cls_base_addr() {
     extern volatile uint32_t __cdata_start, __cdata_end;
@@ -52,11 +45,9 @@ static inline void snrt_init_bss() {
 
     // Only one core needs to perform the initialization
     if (snrt_cluster_idx() == 0 && snrt_is_dm_core()) {
-        volatile uint32_t* p;
-
-        for (p = (uint32_t*)(&__bss_start); p < (uint32_t*)(&__bss_end); p++) {
-            *p = 0;
-        }
+        size_t size = (size_t)(&__bss_end) - (size_t)(&__bss_start);
+        snrt_dma_start_1d_wideptr((uint64_t)(&__bss_start),
+                                  (uint64_t)(snrt_zero_memory_ptr()), size);
     }
 }
 #endif
@@ -70,22 +61,17 @@ static inline void snrt_init_cls() {
 
     // Only one core per cluster has to do this
     if (snrt_is_dm_core()) {
-        volatile uint32_t* p;
-        volatile uint32_t* cls_ptr = (volatile uint32_t*)snrt_cls_base_addr();
+        void* ptr = (void*)snrt_cls_base_addr();
+        size_t size;
 
         // Copy cdata section to base of the TCDM
-        for (p = (uint32_t*)(&__cdata_start); p < (uint32_t*)(&__cdata_end);
-             p++) {
-            *cls_ptr = *p;
-            cls_ptr++;
-        }
+        size = (size_t)(&__cdata_end) - (size_t)(&__cdata_start);
+        if (size > 0) snrt_dma_start_1d(ptr, (void*)(&__cdata_start), size);
 
         // Clear cbss section
-        for (p = (uint32_t*)(&__cbss_start); p < (uint32_t*)(&__cbss_end);
-             p++) {
-            *cls_ptr = 0;
-            cls_ptr++;
-        }
+        ptr = (void*)((uint32_t)ptr + size);
+        size = (size_t)(&__cbss_end) - (size_t)(&__cbss_start);
+        snrt_dma_start_1d(ptr, (void*)(snrt_zero_memory_ptr()), size);
     }
 }
 #endif
@@ -105,7 +91,6 @@ void snrt_main() {
     int exit_code = 0;
 
 #ifdef SNRT_CRT0_CALLBACK0
-
     snrt_crt0_callback0();
 #endif
 
@@ -129,6 +114,11 @@ void snrt_main() {
     snrt_init_cls();
 #endif
 
+#if defined(SNRT_INIT_BSS) || defined(SNRT_INIT_CLS)
+    // Single DMA wait call for both snrt_init_bss() and snrt_init_cls()
+    if (snrt_is_dm_core()) snrt_dma_wait_all();
+#endif
+
 #ifdef SNRT_CRT0_CALLBACK3
     snrt_crt0_callback3();
 #endif
@@ -142,7 +132,7 @@ void snrt_main() {
 #endif
 
 #ifdef SNRT_CRT0_PRE_BARRIER
-    snrt_crt0_cluster_hw_barrier();
+    snrt_cluster_hw_barrier();
 #endif
 
 #ifdef SNRT_CRT0_CALLBACK5
@@ -159,7 +149,7 @@ void snrt_main() {
 #endif
 
 #ifdef SNRT_CRT0_POST_BARRIER
-    snrt_crt0_cluster_hw_barrier();
+    snrt_cluster_hw_barrier();
 #endif
 
 #ifdef SNRT_CRT0_CALLBACK7

diff --git a/sw/snRuntime/src/team.h b/sw/snRuntime/src/team.h
@@ -28,6 +28,11 @@ inline uint32_t __attribute__((const)) snrt_global_core_idx() {
     return snrt_hartid() - snrt_global_core_base_hartid();
 }
 
+inline uint32_t __attribute__((const)) snrt_global_compute_core_idx() {
+    return snrt_cluster_idx() * snrt_cluster_compute_core_num() +
+           snrt_cluster_core_idx();
+}
+
 inline uint32_t __attribute__((const)) snrt_cluster_idx() {
     return snrt_global_core_idx() / snrt_cluster_core_num();
 }

diff --git a/target/common/common.mk b/target/common/common.mk
@@ -6,15 +6,19 @@ LOGS_DIR       ?= logs
 TB_DIR         ?= $(SNITCH_ROOT)/target/common/test
 UTIL_DIR       ?= $(SNITCH_ROOT)/util
 
-# Support for local override
+# External executables
 BENDER		   ?= bender
 DASM 	       ?= spike-dasm
 VLT			   ?= verilator
 VERIBLE_FMT    ?= verible-verilog-format
+CLANG_FORMAT   ?= clang-format
+
+# Internal executables
 BIN2JTAG       ?= $(UTIL_DIR)/bin2jtag.py
-ANNOTATE	   ?= $(UTIL_DIR)/trace/annotate.py
 GENTRACE	   ?= $(UTIL_DIR)/trace/gen_trace.py
-CLANG_FORMAT   ?= clang-format
+ANNOTATE_PY	   ?= $(UTIL_DIR)/trace/annotate.py
+EVENTS_PY	   ?= $(UTIL_DIR)/trace/events.py
+PERF_CSV_PY	   ?= $(UTIL_DIR)/trace/perf_csv.py
 
 VERILATOR_ROOT ?= $(dir $(shell which $(VLT)))/../share/verilator
 VLT_ROOT	   ?= ${VERILATOR_ROOT}
@@ -194,10 +198,10 @@ traces: $(shell (ls $(LOGS_DIR)/trace_hart_*.dasm 2>/dev/null | sed 's/\.dasm/\.
 # make annotate
 # Generate source-code interleaved traces for all harts. Reads the binary from
 # the logs/.rtlbinary file that is written at start of simulation in the vsim script
-$(LOGS_DIR)/trace_hart_%.s: $(LOGS_DIR)/trace_hart_%.txt ${ANNOTATE}
-	$(PYTHON) ${ANNOTATE} ${ANNOTATE_FLAGS} -o $@ $(BINARY) $<
-$(LOGS_DIR)/trace_hart_%.diff: $(LOGS_DIR)/trace_hart_%.txt ${ANNOTATE}
-	$(PYTHON) ${ANNOTATE} ${ANNOTATE_FLAGS} -o $@ $(BINARY) $< -d
+$(LOGS_DIR)/trace_hart_%.s: $(LOGS_DIR)/trace_hart_%.txt ${ANNOTATE_PY}
+	$(PYTHON) ${ANNOTATE_PY} ${ANNOTATE_FLAGS} -o $@ $(BINARY) $<
+$(LOGS_DIR)/trace_hart_%.diff: $(LOGS_DIR)/trace_hart_%.txt ${ANNOTATE_PY}
+	$(PYTHON) ${ANNOTATE_PY} ${ANNOTATE_FLAGS} -o $@ $(BINARY) $< -d
 BINARY ?= $(shell cat $(LOGS_DIR)/.rtlbinary)
 annotate: $(shell (ls $(LOGS_DIR)/trace_hart_*.dasm 2>/dev/null | sed 's/\.dasm/\.s/') || echo "") \
           $(shell (ls $(LOGS_DIR)/trace_hart_*.dasm 2>/dev/null | sed 's/\.dasm/\.diff/') || echo "")

diff --git a/target/snitch_cluster/Makefile b/target/snitch_cluster/Makefile
@@ -266,12 +266,12 @@ bin/snitch_cluster.vcs: ${VCS_SOURCES} ${TB_SRCS} $(TB_CC_SOURCES) $(TB_ASM_SOUR
 ##########
 
 $(LOGS_DIR)/perf.csv: $(shell (ls $(LOGS_DIR)/trace_hart_*.dasm 2>/dev/null | sed 's/trace_hart/hart/' | sed 's/.dasm/_perf.json/')) \
-		$(ROOT)/util/trace/perf_csv.py
-	$(PYTHON) $(ROOT)/util/trace/perf_csv.py -o $@ -i $(LOGS_DIR)/hart_*_perf.json
+		$(PERF_CSV_PY)
+	$(PYTHON) $(PERF_CSV_PY) -o $@ -i $(LOGS_DIR)/hart_*_perf.json
 
 $(LOGS_DIR)/event.csv: $(shell (ls $(LOGS_DIR)/trace_hart_*.dasm 2>/dev/null | sed 's/trace_hart/hart/' | sed 's/.dasm/_perf.json/')) \
-		$(ROOT)/util/trace/perf_csv.py
-	$(PYTHON) $(ROOT)/util/trace/perf_csv.py -o $@ -i $(LOGS_DIR)/hart_*_perf.json --filter tstart tend
+		$(PERF_CSV_PY)
+	$(PYTHON) $(PERF_CSV_PY) -o $@ -i $(LOGS_DIR)/hart_*_perf.json --filter tstart tend
 
 ########
 # Util #

diff --git a/target/snitch_cluster/sw/runtime/common/snitch_cluster_memory.c b/target/snitch_cluster/sw/runtime/common/snitch_cluster_memory.c
@@ -11,3 +11,5 @@ extern volatile uint32_t* snrt_cluster_clint_set_ptr();
 extern volatile uint32_t* snrt_cluster_clint_clr_ptr();
 
 extern uint32_t snrt_cluster_hw_barrier_addr();
+
+extern volatile uint32_t* snrt_zero_memory_ptr();
Original file line number	Diff line number	Diff line change
Expand Up		@@ -11,3 +11,5 @@ extern volatile uint32_t* snrt_cluster_clint_set_ptr();
		extern volatile uint32_t* snrt_cluster_clint_clr_ptr();

		extern uint32_t snrt_cluster_hw_barrier_addr();

		extern volatile uint32_t* snrt_zero_memory_ptr();