Minor fixes

Author: GlassOfWhiskey

src/riscv/api.h

@@ -42,11 +42,29 @@ CPUINFO_INTERNAL void cpuinfo_riscv_decode_vendor_uarch(
 		enum cpuinfo_vendor vendor[restrict static 1],
 		enum cpuinfo_uarch uarch[restrict static 1]);
 
-CPUINFO_INTERNAL void cpuinfo_riscv_decode_cache(
+/**
+ * Decodes the cache hierarchy based on the provided inpu parameters,
+ * regardless of underlying operating system.
+ *
+ * @param[uarch]: The processor micro-architecture code.
+ * @param[l1i] - Reference to the l1i cpuinfo_cache to populate.
+ * @param[l1d]: - Reference to the l1d cpuinfo_cache to populate.
+ * @param[l2]: - Reference to the l2 cpuinfo_cache to populate.
+ * @return false if any error occurred, true otherwise
+ */
+
+CPUINFO_INTERNAL bool cpuinfo_riscv_decode_cache(
         enum cpuinfo_uarch uarch,
         struct cpuinfo_cache l1i[restrict static 1],
         struct cpuinfo_cache l1d[restrict static 1],
         struct cpuinfo_cache l2[restrict static 1]);
 
+/**
+ * Extracts the maximum cache size from a RISC-V processor, independently
+ * of underlying operating system.
+ *
+ * @param[processor]: The RISC-V processor.
+ * @preturn: The maximum cache size.
+ */
 CPUINFO_INTERNAL uint32_t cpuinfo_riscv_compute_max_cache_size(
         const struct cpuinfo_processor processor[restrict static 1]);

src/riscv/cache.c

@@ -4,13 +4,13 @@
 #include <cpuinfo/internal-api.h>
 #include <cpuinfo/log.h>
 
-void cpuinfo_riscv_decode_cache(
+bool cpuinfo_riscv_decode_cache(
         enum cpuinfo_uarch uarch,
         struct cpuinfo_cache l1i[restrict static 1],
         struct cpuinfo_cache l1d[restrict static 1],
-        struct cpuinfo_cache l2[restrict static 1])
-{
+        struct cpuinfo_cache l2[restrict static 1]) {
     switch(uarch) {
+		// According to https://starfivetech.com/uploads/u74mc_core_complex_manual_21G1.pdf
         case cpuinfo_uarch_u74_mc:
            *l1i = (struct cpuinfo_cache) {
                .size = 32 * 1024,
@@ -30,6 +30,7 @@ void cpuinfo_riscv_decode_cache(
            break;
         default:
             cpuinfo_log_warning("target uarch not recognized; cache data is not populated");
+			return false;
     }
     l1i->sets = l1i->size / (l1i->associativity * l1i->line_size);
     l1i->partitions = 1;
@@ -39,14 +40,17 @@ void cpuinfo_riscv_decode_cache(
         l2->sets = l2->size / (l2->associativity * l2->line_size);
         l2->partitions = 1;
     }
+
+	return true;
 }
 
 uint32_t cpuinfo_riscv_compute_max_cache_size(const struct cpuinfo_processor* processor) {
     switch(processor->core->uarch) {
+		// According to https://starfivetech.com/uploads/u74mc_core_complex_manual_21G1.pdf
         case cpuinfo_uarch_u74_mc:
             return 2 * 1024 * 1024;
         default:
-            cpuinfo_log_warning("target uarch not recognized; mas cache size is not populated");
+            cpuinfo_log_warning("target uarch not recognized; max cache size is not populated");
             return 0;
     }
 }

src/riscv/linux/api.h

@@ -86,13 +86,24 @@ CPUINFO_INTERNAL void cpuinfo_riscv_linux_decode_vendor_uarch_from_hwprobe(
 	enum cpuinfo_vendor vendor[restrict static 1],
 	enum cpuinfo_uarch uarch[restrict static 1]);
 
-CPUINFO_INTERNAL void cpuinfo_riscv_linux_count_cluster_processors(
-	uint32_t max_processors,
-	struct cpuinfo_riscv_linux_processor processors[restrict static max_processors]);
+/**
+ * Reads the value of hwcap from the `getauxval` function, or
+ * mocks a fake value for testing purposes
+ *
+ * @param[hwcap] - The hwcap flags to be populated
+ */
 
 CPUINFO_INTERNAL void cpuinfo_riscv_linux_hwcap_from_getauxval(
 	uint32_t hwcap[restrict static 1]);
 
+/**
+ * Parses the output of the `/proc/cpuinfo` command to extract
+ * info about the RISC-V processors.
+ *
+ * @param[max_processors_count] - The maximum number of processors.
+ * @param processors - Reference to the processor list to populate.
+ * @return false if any error occurred, true otherwise.
+ */
 CPUINFO_INTERNAL bool cpuinfo_riscv_linux_parse_proc_cpuinfo(
 	uint32_t max_processors_count,
 	struct cpuinfo_riscv_linux_processor processors[restrict static max_processors_count]);

src/riscv/linux/cpuinfo.c

@@ -21,7 +21,7 @@ static uint32_t parse_processor_number(
 
 	if (processor_length == 0) {
 		cpuinfo_log_warning("Processor number in /proc/cpuinfo is ignored: string is empty");
-		return 0;
+		return -1;
 	}
 
 	uint32_t processor_number = 0;
@@ -45,7 +45,7 @@ static void parse_isa(
 		struct cpuinfo_riscv_linux_processor processor[restrict static 1])
 {
 	const size_t isa_length = (size_t) (isa_end - isa_start);
-	if (!(memcmp(isa_start, "rv32", 4) == 0 || memcmp(isa_start, "rv64", 4) == 0)) {
+	if (isa_length < 4 || !(memcmp(isa_start, "rv32", 4) == 0 || memcmp(isa_start, "rv64", 4) == 0)) {
 		cpuinfo_log_error("Invalid isa format in /proc/cpuinfo: %.*s. It should start with either `rv32` or `rv64`",
 						  (int) (isa_length), isa_start);
 		return;
@@ -178,8 +178,8 @@ static bool parse_line(
 	}
 	/* Skip line if no ':' separator was found. */
 	if (separator == line_end) {
-		cpuinfo_log_info("Line %.*s in /proc/cpuinfo is ignored: key/value separator ':' not found",
-						 (int) (line_end - line_start), line_start);
+		cpuinfo_log_warning("Line %.*s in /proc/cpuinfo is ignored: key/value separator ':' not found",
+							(int) (line_end - line_start), line_start);
 		return true;
 	}
 
@@ -238,13 +238,6 @@ static bool parse_line(
 				goto unknown;
 			}
 			break;
-		case 4:
-			if (memcmp(line_start, "hart", key_length) == 0) {
-				// Do nothing
-			} else {
-				goto unknown;
-			}
-			break;
 		case 5:
 			if (memcmp(line_start, "uarch", key_length) == 0) {
 				parse_uarch(value_start, value_end, processor);
@@ -255,7 +248,10 @@ static bool parse_line(
 		case 9:
 			if (memcmp(line_start, "processor", key_length) == 0) {
 				const uint32_t new_processor_index = parse_processor_number(value_start, value_end);
-				if (new_processor_index < processor_index) {
+				if (new_processor_index < 0) {
+					/* Strange: empty string */
+					break;
+				} else if (new_processor_index < processor_index) {
 					/* Strange: decreasing processor number */
 					cpuinfo_log_warning(
 						"unexpectedly low processor number %"PRIu32" following processor %"PRIu32" in /proc/cpuinfo",
@@ -280,6 +276,8 @@ static bool parse_line(
 			}
 			break;
 		default:
+			// Do nothing
+			break;
 		unknown:
 			cpuinfo_log_debug("unknown /proc/cpuinfo key: %.*s", (int) key_length, line_start);
 	}

src/riscv/linux/hwcap.c

@@ -2,28 +2,16 @@
 
 #if CPUINFO_MOCK
 	#include <cpuinfo-mock.h>
-#endif
-
-#if CPUINFO_ARCH_RISCV32 || CPUINFO_ARCH_RISCV64
-	#include <sys/auxv.h>
-#else
-	#define AT_HWCAP 16
-	#define AT_HWCAP2 26
-#endif
 
-#if CPUINFO_MOCK
 	static uint32_t mock_hwcap = 0;
 	void cpuinfo_set_hwcap(uint32_t hwcap) {
 		mock_hwcap = hwcap;
 	}
-
-	static uint32_t mock_hwcap2 = 0;
-	void cpuinfo_set_hwcap2(uint32_t hwcap2) {
-		mock_hwcap2 = hwcap2;
-	}
 #endif
 
 #if CPUINFO_ARCH_RISCV32 || CPUINFO_ARCH_RISCV64
+	#include <sys/auxv.h>
+
 	void cpuinfo_riscv_linux_hwcap_from_getauxval(
 		uint32_t hwcap[restrict static 1])
 	{

src/riscv/linux/init.c

@@ -447,7 +447,7 @@ void cpuinfo_riscv_linux_init(void) {
 	enum cpuinfo_uarch last_uarch = cpuinfo_uarch_unknown;
 	for (size_t processor = 0; processor < riscv_linux_processors_count; processor++) {
 		if (!bitmask_all(riscv_linux_processors[processor].flags, CPUINFO_LINUX_FLAG_VALID)) {
-			continue;
+			break;
 		}
 
 		/**
@@ -627,15 +627,16 @@ void cpuinfo_riscv_linux_init(void) {
 
 		/* Populate cache information structures in l1i, l1d */
 		struct cpuinfo_cache temp_l2 = { 0 };
-		cpuinfo_riscv_decode_cache(
+		if (cpuinfo_riscv_decode_cache(
 				riscv_linux_processors[processor].core.uarch,
-				&l1i[processor], &l1d[processor], &temp_l2);
-		l1i[processor].processor_start = l1d[processor].processor_start = processor;
-		l1i[processor].processor_count = l1d[processor].processor_count = 1;
-		if (temp_l2.size != 0) {
-			/* Assume L2 is shared by cores in the same cluster */
-			if (riscv_linux_processors[processor].package_leader_id == linux_id) {
-				l2_count += 1;
+				&l1i[processor], &l1d[processor], &temp_l2)) {
+			l1i[processor].processor_start = l1d[processor].processor_start = processor;
+			l1i[processor].processor_count = l1d[processor].processor_count = 1;
+			if (temp_l2.size != 0) {
+				/* Assume L2 is shared by cores in the same cluster */
+				if (riscv_linux_processors[processor].cluster_leader_id == linux_id) {
+					l2_count += 1;
+				}
 			}
 		}
 
@@ -669,25 +670,27 @@ void cpuinfo_riscv_linux_init(void) {
 	uint32_t l2_index = UINT32_MAX;
 	for (uint32_t processor = 0; processor < valid_processors_count; processor++) {
 		struct cpuinfo_cache dummy_l1i, dummy_l1d, temp_l2 = { 0 };
-		cpuinfo_riscv_decode_cache(
+		if (cpuinfo_riscv_decode_cache(
 				riscv_linux_processors[processor].core.uarch,
-				&dummy_l1i, &dummy_l1d, &temp_l2);
-
-		if (temp_l2.size != 0) {
-			if (riscv_linux_processors[processor].package_leader_id == riscv_linux_processors[processor].processor.linux_id) {
-				l2_index += 1;
-				l2[l2_index] = (struct cpuinfo_cache) {
-						.size            = temp_l2.size,
-						.associativity   = temp_l2.associativity,
-						.sets            = temp_l2.sets,
-						.partitions      = temp_l2.partitions,
-						.line_size       = temp_l2.line_size,
-						.flags           = temp_l2.flags,
-						.processor_start = processor,
-						.processor_count = riscv_linux_processors[processor].package.processor_count,
-				};
+				&dummy_l1i, &dummy_l1d, &temp_l2)) {
+
+			if (temp_l2.size != 0) {
+				if (riscv_linux_processors[processor].cluster_leader_id ==
+					riscv_linux_processors[processor].processor.linux_id) {
+					l2_index += 1;
+					l2[l2_index] = (struct cpuinfo_cache) {
+							.size            = temp_l2.size,
+							.associativity   = temp_l2.associativity,
+							.sets            = temp_l2.sets,
+							.partitions      = temp_l2.partitions,
+							.line_size       = temp_l2.line_size,
+							.flags           = temp_l2.flags,
+							.processor_start = processor,
+							.processor_count = riscv_linux_processors[processor].package.processor_count,
+					};
+				}
+				processors[processor].cache.l2 = l2 + l2_index;
 			}
-			processors[processor].cache.l2 = l2 + l2_index;
 		}
 	}
 

src/riscv/linux/riscv-isa.c

@@ -6,7 +6,7 @@
 
 void cpuinfo_riscv_linux_decode_isa_from_hwcap(
 		struct cpuinfo_riscv_isa isa[restrict static 1]) {
-	unsigned long hwcap = 0;
+	uint32_t hwcap = 0;
 	cpuinfo_riscv_linux_hwcap_from_getauxval(&hwcap);
 
 	if (hwcap & CPUINFO_RISCV_LINUX_FEATURE_I) {