1 files changed, 188 insertions, 35 deletions

diff --git a/arch/riscv/kernel/sys_hwprobe.c b/arch/riscv/kernel/sys_hwprobe.c
index 969ef3d59dbe..0f701ace3bb9 100644
--- a/arch/riscv/kernel/sys_hwprobe.c
+++ b/arch/riscv/kernel/sys_hwprobe.c
@@ -5,14 +5,22 @@
  * more details.
  */
 #include <linux/syscalls.h>
+#include <linux/completion.h>
+#include <linux/atomic.h>
+#include <linux/once.h>
 #include <asm/cacheflush.h>
 #include <asm/cpufeature.h>
 #include <asm/hwprobe.h>
+#include <asm/processor.h>
+#include <asm/delay.h>
 #include <asm/sbi.h>
 #include <asm/switch_to.h>
 #include <asm/uaccess.h>
 #include <asm/unistd.h>
 #include <asm/vector.h>
+#include <asm/vendor_extensions/mips_hwprobe.h>
+#include <asm/vendor_extensions/sifive_hwprobe.h>
+#include <asm/vendor_extensions/thead_hwprobe.h>
 #include <vdso/vsyscall.h>
 
 
@@ -23,6 +31,11 @@ static void hwprobe_arch_id(struct riscv_hwprobe *pair,
 	bool first = true;
 	int cpu;
 
+	if (pair->key != RISCV_HWPROBE_KEY_MVENDORID &&
+	    pair->key != RISCV_HWPROBE_KEY_MIMPID &&
+	    pair->key != RISCV_HWPROBE_KEY_MARCHID)
+		goto out;
+
 	for_each_cpu(cpu, cpus) {
 		u64 cpu_id;
 
@@ -53,6 +66,7 @@ static void hwprobe_arch_id(struct riscv_hwprobe *pair,
 		}
 	}
 
+out:
 	pair->value = id;
 }
 
@@ -69,7 +83,7 @@ static void hwprobe_isa_ext0(struct riscv_hwprobe *pair,
 	if (riscv_isa_extension_available(NULL, c))
 		pair->value |= RISCV_HWPROBE_IMA_C;
 
-	if (has_vector())
+	if (has_vector() && riscv_isa_extension_available(NULL, v))
 		pair->value |= RISCV_HWPROBE_IMA_V;
 
 	/*
@@ -92,30 +106,55 @@ static void hwprobe_isa_ext0(struct riscv_hwprobe *pair,
 		 * regardless of the kernel's configuration, as no other checks, besides
 		 * presence in the hart_isa bitmap, are made.
 		 */
+		EXT_KEY(ZAAMO);
+		EXT_KEY(ZABHA);
+		EXT_KEY(ZACAS);
+		EXT_KEY(ZALASR);
+		EXT_KEY(ZALRSC);
+		EXT_KEY(ZAWRS);
 		EXT_KEY(ZBA);
 		EXT_KEY(ZBB);
-		EXT_KEY(ZBS);
-		EXT_KEY(ZICBOZ);
 		EXT_KEY(ZBC);
-
 		EXT_KEY(ZBKB);
 		EXT_KEY(ZBKC);
 		EXT_KEY(ZBKX);
+		EXT_KEY(ZBS);
+		EXT_KEY(ZCA);
+		EXT_KEY(ZCB);
+		EXT_KEY(ZCMOP);
+		EXT_KEY(ZICBOM);
+		EXT_KEY(ZICBOP);
+		EXT_KEY(ZICBOZ);
+		EXT_KEY(ZICNTR);
+		EXT_KEY(ZICOND);
+		EXT_KEY(ZIHINTNTL);
+		EXT_KEY(ZIHINTPAUSE);
+		EXT_KEY(ZIHPM);
+		EXT_KEY(ZIMOP);
 		EXT_KEY(ZKND);
 		EXT_KEY(ZKNE);
 		EXT_KEY(ZKNH);
 		EXT_KEY(ZKSED);
 		EXT_KEY(ZKSH);
 		EXT_KEY(ZKT);
-		EXT_KEY(ZIHINTNTL);
 		EXT_KEY(ZTSO);
-		EXT_KEY(ZACAS);
-		EXT_KEY(ZICOND);
-		EXT_KEY(ZIHINTPAUSE);
 
+		/*
+		 * All the following extensions must depend on the kernel
+		 * support of V.
+		 */
 		if (has_vector()) {
 			EXT_KEY(ZVBB);
 			EXT_KEY(ZVBC);
+			EXT_KEY(ZVE32F);
+			EXT_KEY(ZVE32X);
+			EXT_KEY(ZVE64D);
+			EXT_KEY(ZVE64F);
+			EXT_KEY(ZVE64X);
+			EXT_KEY(ZVFBFMIN);
+			EXT_KEY(ZVFBFWMA);
+			EXT_KEY(ZVFH);
+			EXT_KEY(ZVFHMIN);
 			EXT_KEY(ZVKB);
 			EXT_KEY(ZVKG);
 			EXT_KEY(ZVKNED);
@@ -124,15 +163,17 @@ static void hwprobe_isa_ext0(struct riscv_hwprobe *pair,
 			EXT_KEY(ZVKSED);
 			EXT_KEY(ZVKSH);
 			EXT_KEY(ZVKT);
-			EXT_KEY(ZVFH);
-			EXT_KEY(ZVFHMIN);
 		}
 
-		if (has_fpu()) {
-			EXT_KEY(ZFH);
-			EXT_KEY(ZFHMIN);
-			EXT_KEY(ZFA);
-		}
+		EXT_KEY(ZCD);
+		EXT_KEY(ZCF);
+		EXT_KEY(ZFA);
+		EXT_KEY(ZFBFMIN);
+		EXT_KEY(ZFH);
+		EXT_KEY(ZFHMIN);
+
+		if (IS_ENABLED(CONFIG_RISCV_ISA_SUPM))
+			EXT_KEY(SUPM);
 #undef EXT_KEY
 	}
 
@@ -140,7 +181,7 @@ static void hwprobe_isa_ext0(struct riscv_hwprobe *pair,
 	pair->value &= ~missing;
 }
 
-static bool hwprobe_ext0_has(const struct cpumask *cpus, unsigned long ext)
+static bool hwprobe_ext0_has(const struct cpumask *cpus, u64 ext)
 {
 	struct riscv_hwprobe pair;
 
@@ -161,13 +202,13 @@ static u64 hwprobe_misaligned(const struct cpumask *cpus)
 			perf = this_perf;
 
 		if (perf != this_perf) {
-			perf = RISCV_HWPROBE_MISALIGNED_UNKNOWN;
+			perf = RISCV_HWPROBE_MISALIGNED_SCALAR_UNKNOWN;
 			break;
 		}
 	}
 
 	if (perf == -1ULL)
-		return RISCV_HWPROBE_MISALIGNED_UNKNOWN;
+		return RISCV_HWPROBE_MISALIGNED_SCALAR_UNKNOWN;
 
 	return perf;
 }
@@ -175,12 +216,49 @@ static u64 hwprobe_misaligned(const struct cpumask *cpus)
 static u64 hwprobe_misaligned(const struct cpumask *cpus)
 {
 	if (IS_ENABLED(CONFIG_RISCV_EFFICIENT_UNALIGNED_ACCESS))
-		return RISCV_HWPROBE_MISALIGNED_FAST;
+		return RISCV_HWPROBE_MISALIGNED_SCALAR_FAST;
 
 	if (IS_ENABLED(CONFIG_RISCV_EMULATED_UNALIGNED_ACCESS) && unaligned_ctl_available())
-		return RISCV_HWPROBE_MISALIGNED_EMULATED;
+		return RISCV_HWPROBE_MISALIGNED_SCALAR_EMULATED;
 
-	return RISCV_HWPROBE_MISALIGNED_SLOW;
+	return RISCV_HWPROBE_MISALIGNED_SCALAR_SLOW;
+}
+#endif
+
+#ifdef CONFIG_RISCV_VECTOR_MISALIGNED
+static u64 hwprobe_vec_misaligned(const struct cpumask *cpus)
+{
+	int cpu;
+	u64 perf = -1ULL;
+
+	/* Return if supported or not even if speed wasn't probed */
+	for_each_cpu(cpu, cpus) {
+		int this_perf = per_cpu(vector_misaligned_access, cpu);
+
+		if (perf == -1ULL)
+			perf = this_perf;
+
+		if (perf != this_perf) {
+			perf = RISCV_HWPROBE_MISALIGNED_VECTOR_UNKNOWN;
+			break;
+		}
+	}
+
+	if (perf == -1ULL)
+		return RISCV_HWPROBE_MISALIGNED_VECTOR_UNKNOWN;
+
+	return perf;
+}
+#else
+static u64 hwprobe_vec_misaligned(const struct cpumask *cpus)
+{
+	if (IS_ENABLED(CONFIG_RISCV_EFFICIENT_VECTOR_UNALIGNED_ACCESS))
+		return RISCV_HWPROBE_MISALIGNED_VECTOR_FAST;
+
+	if (IS_ENABLED(CONFIG_RISCV_SLOW_VECTOR_UNALIGNED_ACCESS))
+		return RISCV_HWPROBE_MISALIGNED_VECTOR_SLOW;
+
+	return RISCV_HWPROBE_MISALIGNED_VECTOR_UNKNOWN;
 }
 #endif
 
@@ -208,14 +286,47 @@ static void hwprobe_one_pair(struct riscv_hwprobe *pair,
 		break;
 
 	case RISCV_HWPROBE_KEY_CPUPERF_0:
+	case RISCV_HWPROBE_KEY_MISALIGNED_SCALAR_PERF:
 		pair->value = hwprobe_misaligned(cpus);
 		break;
 
+	case RISCV_HWPROBE_KEY_MISALIGNED_VECTOR_PERF:
+		pair->value = hwprobe_vec_misaligned(cpus);
+		break;
+
 	case RISCV_HWPROBE_KEY_ZICBOZ_BLOCK_SIZE:
 		pair->value = 0;
 		if (hwprobe_ext0_has(cpus, RISCV_HWPROBE_EXT_ZICBOZ))
 			pair->value = riscv_cboz_block_size;
 		break;
+	case RISCV_HWPROBE_KEY_ZICBOM_BLOCK_SIZE:
+		pair->value = 0;
+		if (hwprobe_ext0_has(cpus, RISCV_HWPROBE_EXT_ZICBOM))
+			pair->value = riscv_cbom_block_size;
+		break;
+	case RISCV_HWPROBE_KEY_ZICBOP_BLOCK_SIZE:
+		pair->value = 0;
+		if (hwprobe_ext0_has(cpus, RISCV_HWPROBE_EXT_ZICBOP))
+			pair->value = riscv_cbop_block_size;
+		break;
+	case RISCV_HWPROBE_KEY_HIGHEST_VIRT_ADDRESS:
+		pair->value = user_max_virt_addr();
+		break;
+
+	case RISCV_HWPROBE_KEY_TIME_CSR_FREQ:
+		pair->value = riscv_timebase;
+		break;
+
+	case RISCV_HWPROBE_KEY_VENDOR_EXT_SIFIVE_0:
+		hwprobe_isa_vendor_ext_sifive_0(pair, cpus);
+		break;
+
+	case RISCV_HWPROBE_KEY_VENDOR_EXT_THEAD_0:
+		hwprobe_isa_vendor_ext_thead_0(pair, cpus);
+		break;
+	case RISCV_HWPROBE_KEY_VENDOR_EXT_MIPS_0:
+		hwprobe_isa_vendor_ext_mips_0(pair, cpus);
+		break;
 
 	/*
 	 * For forward compatibility, unknown keys don't fail the whole
@@ -359,29 +470,32 @@ static int hwprobe_get_cpus(struct riscv_hwprobe __user *pairs,
 	return 0;
 }
 
-static int do_riscv_hwprobe(struct riscv_hwprobe __user *pairs,
-			    size_t pair_count, size_t cpusetsize,
-			    unsigned long __user *cpus_user,
-			    unsigned int flags)
-{
-	if (flags & RISCV_HWPROBE_WHICH_CPUS)
-		return hwprobe_get_cpus(pairs, pair_count, cpusetsize,
-					cpus_user, flags);
+#ifdef CONFIG_MMU
 
-	return hwprobe_get_values(pairs, pair_count, cpusetsize,
-				  cpus_user, flags);
+static DECLARE_COMPLETION(boot_probes_done);
+static atomic_t pending_boot_probes = ATOMIC_INIT(1);
+
+void riscv_hwprobe_register_async_probe(void)
+{
+	atomic_inc(&pending_boot_probes);
 }
 
-#ifdef CONFIG_MMU
+void riscv_hwprobe_complete_async_probe(void)
+{
+	if (atomic_dec_and_test(&pending_boot_probes))
+		complete(&boot_probes_done);
+}
 
-static int __init init_hwprobe_vdso_data(void)
+static int complete_hwprobe_vdso_data(void)
 {
-	struct vdso_data *vd = __arch_get_k_vdso_data();
-	struct arch_vdso_data *avd = &vd->arch_data;
+	struct vdso_arch_data *avd = vdso_k_arch_data;
 	u64 id_bitsmash = 0;
 	struct riscv_hwprobe pair;
 	int key;
 
+	if (unlikely(!atomic_dec_and_test(&pending_boot_probes)))
+		wait_for_completion(&boot_probes_done);
+
 	/*
 	 * Initialize vDSO data with the answers for the "all CPUs" case, to
 	 * save a syscall in the common case.
@@ -409,13 +523,52 @@ static int __init init_hwprobe_vdso_data(void)
 	 * vDSO should defer to the kernel for exotic cpu masks.
 	 */
 	avd->homogeneous_cpus = id_bitsmash != 0 && id_bitsmash != -1;
+
+	/*
+	 * Make sure all the VDSO values are visible before we look at them.
+	 * This pairs with the implicit "no speculativly visible accesses"
+	 * barrier in the VDSO hwprobe code.
+	 */
+	smp_wmb();
+	avd->ready = true;
+	return 0;
+}
+
+static int __init init_hwprobe_vdso_data(void)
+{
+	struct vdso_arch_data *avd = vdso_k_arch_data;
+
+	/*
+	 * Prevent the vDSO cached values from being used, as they're not ready
+	 * yet.
+	 */
+	avd->ready = false;
 	return 0;
 }
 
 arch_initcall_sync(init_hwprobe_vdso_data);
 
+#else
+
+static int complete_hwprobe_vdso_data(void) { return 0; }
+
 #endif /* CONFIG_MMU */
 
+static int do_riscv_hwprobe(struct riscv_hwprobe __user *pairs,
+			    size_t pair_count, size_t cpusetsize,
+			    unsigned long __user *cpus_user,
+			    unsigned int flags)
+{
+	DO_ONCE_SLEEPABLE(complete_hwprobe_vdso_data);
+
+	if (flags & RISCV_HWPROBE_WHICH_CPUS)
+		return hwprobe_get_cpus(pairs, pair_count, cpusetsize,
+					cpus_user, flags);
+
+	return hwprobe_get_values(pairs, pair_count, cpusetsize,
+				cpus_user, flags);
+}
+
 SYSCALL_DEFINE5(riscv_hwprobe, struct riscv_hwprobe __user *, pairs,
 		size_t, pair_count, size_t, cpusetsize, unsigned long __user *,
 		cpus, unsigned int, flags)