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-rw-r--r--drivers/imx/timer/imx_gpt.c62
1 files changed, 62 insertions, 0 deletions
diff --git a/drivers/imx/timer/imx_gpt.c b/drivers/imx/timer/imx_gpt.c
new file mode 100644
index 0000000..464efe9
--- /dev/null
+++ b/drivers/imx/timer/imx_gpt.c
@@ -0,0 +1,62 @@
+/*
+ * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <assert.h>
+
+#include <drivers/delay_timer.h>
+#include <lib/mmio.h>
+
+#include <imx_gpt.h>
+
+#define GPTCR_SWR BIT(15) /* Software reset */
+#define GPTCR_24MEN BIT(10) /* Enable 24MHz clock input */
+#define GPTCR_CLKSOURCE_OSC (5 << 6) /* Clock source OSC */
+#define GPTCR_CLKSOURCE_MASK (0x7 << 6)
+#define GPTCR_TEN 1 /* Timer enable */
+
+#define GPTPR_PRESCL_24M_SHIFT 12
+
+#define SYS_COUNTER_FREQ_IN_MHZ 3
+
+#define GPTPR_TIMER_CTRL (imx_base_addr + 0x000)
+#define GPTPR_TIMER_PRESCL (imx_base_addr + 0x004)
+#define GPTPR_TIMER_CNTR (imx_base_addr + 0x024)
+
+static uintptr_t imx_base_addr;
+
+uint32_t imx_get_timer_value(void)
+{
+ return ~mmio_read_32(GPTPR_TIMER_CNTR);
+}
+
+static const timer_ops_t imx_gpt_ops = {
+ .get_timer_value = imx_get_timer_value,
+ .clk_mult = 1,
+ .clk_div = SYS_COUNTER_FREQ_IN_MHZ,
+};
+
+void imx_gpt_ops_init(uintptr_t base_addr)
+{
+ int val;
+
+ assert(base_addr != 0);
+
+ imx_base_addr = base_addr;
+
+ /* setup GP Timer */
+ mmio_write_32(GPTPR_TIMER_CTRL, GPTCR_SWR);
+ mmio_write_32(GPTPR_TIMER_CTRL, 0);
+
+ /* get 3MHz from 24MHz */
+ mmio_write_32(GPTPR_TIMER_PRESCL, (7 << GPTPR_PRESCL_24M_SHIFT));
+
+ val = mmio_read_32(GPTPR_TIMER_CTRL);
+ val &= ~GPTCR_CLKSOURCE_MASK;
+ val |= GPTCR_24MEN | GPTCR_CLKSOURCE_OSC | GPTCR_TEN;
+ mmio_write_32(GPTPR_TIMER_CTRL, val);
+
+ timer_init(&imx_gpt_ops);
+}