From 6778948f9de86c3cfaf36725a7c87dcff9ba247f Mon Sep 17 00:00:00 2001
From: hc <hc@nodka.com>
Date: Mon, 11 Dec 2023 08:20:59 +0000
Subject: [PATCH] kernel_5.10 no rt
---
kernel/arch/riscv/include/asm/timex.h | 97 ++++++++++++++++++++++++++++++++----------------
1 files changed, 64 insertions(+), 33 deletions(-)
diff --git a/kernel/arch/riscv/include/asm/timex.h b/kernel/arch/riscv/include/asm/timex.h
index 2f26989..a066978 100644
--- a/kernel/arch/riscv/include/asm/timex.h
+++ b/kernel/arch/riscv/include/asm/timex.h
@@ -1,56 +1,87 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (C) 2012 Regents of the University of California
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation, version 2.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
*/
#ifndef _ASM_RISCV_TIMEX_H
#define _ASM_RISCV_TIMEX_H
-#include <asm/param.h>
+#include <asm/csr.h>
typedef unsigned long cycles_t;
-static inline cycles_t get_cycles_inline(void)
-{
- cycles_t n;
+#ifdef CONFIG_RISCV_M_MODE
- __asm__ __volatile__ (
- "rdtime %0"
- : "=r" (n));
- return n;
-}
-#define get_cycles get_cycles_inline
+#include <asm/clint.h>
#ifdef CONFIG_64BIT
-static inline uint64_t get_cycles64(void)
+static inline cycles_t get_cycles(void)
{
- return get_cycles();
+ return readq_relaxed(clint_time_val);
}
-#else
-static inline uint64_t get_cycles64(void)
+#else /* !CONFIG_64BIT */
+static inline u32 get_cycles(void)
{
- u32 lo, hi, tmp;
- __asm__ __volatile__ (
- "1:\n"
- "rdtimeh %0\n"
- "rdtime %1\n"
- "rdtimeh %2\n"
- "bne %0, %2, 1b"
- : "=&r" (hi), "=&r" (lo), "=&r" (tmp));
+ return readl_relaxed(((u32 *)clint_time_val));
+}
+#define get_cycles get_cycles
+
+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();
+}
+#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)
+{
+ 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;
+
+ do {
+ hi = get_cycles_hi();
+ lo = get_cycles();
+ } while (hi != get_cycles_hi());
+
return ((u64)hi << 32) | lo;
}
-#endif
+#endif /* CONFIG_64BIT */
#define ARCH_HAS_READ_CURRENT_TIMER
-
static inline int read_current_timer(unsigned long *timer_val)
{
*timer_val = get_cycles();
--
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