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Diffstat (limited to 'roms/u-boot/drivers/timer/riscv_timer.c')
-rw-r--r--roms/u-boot/drivers/timer/riscv_timer.c73
1 files changed, 73 insertions, 0 deletions
diff --git a/roms/u-boot/drivers/timer/riscv_timer.c b/roms/u-boot/drivers/timer/riscv_timer.c
new file mode 100644
index 000000000..3627ed79b
--- /dev/null
+++ b/roms/u-boot/drivers/timer/riscv_timer.c
@@ -0,0 +1,73 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2020, Sean Anderson <seanga2@gmail.com>
+ * Copyright (C) 2018, Bin Meng <bmeng.cn@gmail.com>
+ * Copyright (C) 2018, Anup Patel <anup@brainfault.org>
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ * RISC-V architecturally-defined generic timer driver
+ *
+ * This driver provides generic timer support for S-mode U-Boot.
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <errno.h>
+#include <timer.h>
+#include <asm/csr.h>
+
+static u64 notrace riscv_timer_get_count(struct udevice *dev)
+{
+ __maybe_unused u32 hi, lo;
+
+ if (IS_ENABLED(CONFIG_64BIT))
+ return csr_read(CSR_TIME);
+
+ do {
+ hi = csr_read(CSR_TIMEH);
+ lo = csr_read(CSR_TIME);
+ } while (hi != csr_read(CSR_TIMEH));
+
+ return ((u64)hi << 32) | lo;
+}
+
+#if CONFIG_IS_ENABLED(RISCV_SMODE) && IS_ENABLED(CONFIG_TIMER_EARLY)
+/**
+ * timer_early_get_rate() - Get the timer rate before driver model
+ */
+unsigned long notrace timer_early_get_rate(void)
+{
+ return RISCV_SMODE_TIMER_FREQ;
+}
+
+/**
+ * timer_early_get_count() - Get the timer count before driver model
+ *
+ */
+u64 notrace timer_early_get_count(void)
+{
+ return riscv_timer_get_count(NULL);
+}
+#endif
+
+static int riscv_timer_probe(struct udevice *dev)
+{
+ struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev);
+
+ /* clock frequency was passed from the cpu driver as driver data */
+ uc_priv->clock_rate = dev->driver_data;
+
+ return 0;
+}
+
+static const struct timer_ops riscv_timer_ops = {
+ .get_count = riscv_timer_get_count,
+};
+
+U_BOOT_DRIVER(riscv_timer) = {
+ .name = "riscv_timer",
+ .id = UCLASS_TIMER,
+ .probe = riscv_timer_probe,
+ .ops = &riscv_timer_ops,
+ .flags = DM_FLAG_PRE_RELOC,
+};