1 files changed, 44 insertions, 18 deletions

diff --git a/arch/riscv/include/asm/timex.h b/arch/riscv/include/asm/timex.h
index bad2a7c2cda5..a06697846e69 100644
--- a/arch/riscv/include/asm/timex.h
+++ b/arch/riscv/include/asm/timex.h
@@ -7,41 +7,67 @@
 #define _ASM_RISCV_TIMEX_H
 
 #include <asm/csr.h>
-#include <asm/mmio.h>
 
 typedef unsigned long cycles_t;
 
-extern u64 __iomem *riscv_time_val;
-extern u64 __iomem *riscv_time_cmp;
+#ifdef CONFIG_RISCV_M_MODE
 
-#ifdef CONFIG_64BIT
-#define mmio_get_cycles()	readq_relaxed(riscv_time_val)
-#else
-#define mmio_get_cycles()	readl_relaxed(riscv_time_val)
-#define mmio_get_cycles_hi()	readl_relaxed(((u32 *)riscv_time_val) + 1)
-#endif
+#include <asm/clint.h>
 
+#ifdef CONFIG_64BIT
 static inline cycles_t get_cycles(void)
 {
-	if (IS_ENABLED(CONFIG_RISCV_SBI))
-		return csr_read(CSR_TIME);
-	return mmio_get_cycles();
+	return readq_relaxed(clint_time_val);
+}
+#else /* !CONFIG_64BIT */
+static inline u32 get_cycles(void)
+{
+	return readl_relaxed(((u32 *)clint_time_val));
 }
 #define get_cycles get_cycles
 
-#ifdef CONFIG_64BIT
-static inline u64 get_cycles64(void)
+static inline u32 get_cycles_hi(void)
 {
+	return readl_relaxed(((u32 *)clint_time_val) + 1);
+}
+#define get_cycles_hi get_cycles_hi
+#endif /* CONFIG_64BIT */
+
+/*
+ * Much like MIPS, we may not have a viable counter to use at an early point
+ * in the boot process. Unfortunately we don't have a fallback, so instead
+ * we just return 0.
+ */
+static inline unsigned long random_get_entropy(void)
+{
+	if (unlikely(clint_time_val == NULL))
+		return random_get_entropy_fallback();
 	return get_cycles();
 }
-#else /* CONFIG_64BIT */
+#define random_get_entropy()	random_get_entropy()
+
+#else /* CONFIG_RISCV_M_MODE */
+
+static inline cycles_t get_cycles(void)
+{
+	return csr_read(CSR_TIME);
+}
+#define get_cycles get_cycles
+
 static inline u32 get_cycles_hi(void)
 {
-	if (IS_ENABLED(CONFIG_RISCV_SBI))
-		return csr_read(CSR_TIMEH);
-	return mmio_get_cycles_hi();
+	return csr_read(CSR_TIMEH);
 }
+#define get_cycles_hi get_cycles_hi
 
+#endif /* !CONFIG_RISCV_M_MODE */
+
+#ifdef CONFIG_64BIT
+static inline u64 get_cycles64(void)
+{
+	return get_cycles();
+}
+#else /* CONFIG_64BIT */
 static inline u64 get_cycles64(void)
 {
 	u32 hi, lo;