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-rw-r--r--arch/arm/mach-imx/timer.c139
1 files changed, 139 insertions, 0 deletions
diff --git a/arch/arm/mach-imx/timer.c b/arch/arm/mach-imx/timer.c
new file mode 100644
index 0000000000..9b011147d6
--- /dev/null
+++ b/arch/arm/mach-imx/timer.c
@@ -0,0 +1,139 @@
+/*
+ * (C) Copyright 2007
+ * Sascha Hauer, Pengutronix
+ *
+ * (C) Copyright 2009 Freescale Semiconductor, Inc.
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <div64.h>
+#include <asm/arch/imx-regs.h>
+#include <asm/arch/clock.h>
+#include <asm/arch/sys_proto.h>
+
+/* General purpose timers registers */
+struct mxc_gpt {
+ unsigned int control;
+ unsigned int prescaler;
+ unsigned int status;
+ unsigned int nouse[6];
+ unsigned int counter;
+};
+
+static struct mxc_gpt *cur_gpt = (struct mxc_gpt *)GPT1_BASE_ADDR;
+
+/* General purpose timers bitfields */
+#define GPTCR_SWR (1 << 15) /* Software reset */
+#define GPTCR_24MEN (1 << 10) /* Enable 24MHz clock input */
+#define GPTCR_FRR (1 << 9) /* Freerun / restart */
+#define GPTCR_CLKSOURCE_32 (4 << 6) /* Clock source 32khz */
+#define GPTCR_CLKSOURCE_OSC (5 << 6) /* Clock source OSC */
+#define GPTCR_CLKSOURCE_PRE (1 << 6) /* Clock source PRECLK */
+#define GPTCR_CLKSOURCE_MASK (0x7 << 6)
+#define GPTCR_TEN 1 /* Timer enable */
+
+#define GPTPR_PRESCALER24M_SHIFT 12
+#define GPTPR_PRESCALER24M_MASK (0xF << GPTPR_PRESCALER24M_SHIFT)
+
+DECLARE_GLOBAL_DATA_PTR;
+
+static inline int gpt_has_clk_source_osc(void)
+{
+#if defined(CONFIG_MX6)
+ if (((is_mx6dq()) && (soc_rev() > CHIP_REV_1_0)) ||
+ is_mx6dqp() || is_mx6sdl() || is_mx6sx() || is_mx6ul() ||
+ is_mx6ull() || is_mx6sll())
+ return 1;
+
+ return 0;
+#else
+ return 0;
+#endif
+}
+
+static inline ulong gpt_get_clk(void)
+{
+#ifdef CONFIG_MXC_GPT_HCLK
+ if (gpt_has_clk_source_osc())
+ return MXC_HCLK >> 3;
+ else
+ return mxc_get_clock(MXC_IPG_PERCLK);
+#else
+ return MXC_CLK32;
+#endif
+}
+
+int timer_init(void)
+{
+ int i;
+
+ /* setup GP Timer 1 */
+ __raw_writel(GPTCR_SWR, &cur_gpt->control);
+
+ /* We have no udelay by now */
+ for (i = 0; i < 100; i++)
+ __raw_writel(0, &cur_gpt->control);
+
+ i = __raw_readl(&cur_gpt->control);
+ i &= ~GPTCR_CLKSOURCE_MASK;
+
+#ifdef CONFIG_MXC_GPT_HCLK
+ if (gpt_has_clk_source_osc()) {
+ i |= GPTCR_CLKSOURCE_OSC | GPTCR_TEN;
+
+ /*
+ * For DL/S, SX, UL, ULL, SLL set 24Mhz OSC
+ * Enable bit and prescaler
+ */
+ if (is_mx6sdl() || is_mx6sx() || is_mx6ul() || is_mx6ull() ||
+ is_mx6sll()) {
+ i |= GPTCR_24MEN;
+
+ /* Produce 3Mhz clock */
+ __raw_writel((7 << GPTPR_PRESCALER24M_SHIFT),
+ &cur_gpt->prescaler);
+ }
+ } else {
+ i |= GPTCR_CLKSOURCE_PRE | GPTCR_TEN;
+ }
+#else
+ __raw_writel(0, &cur_gpt->prescaler); /* 32Khz */
+ i |= GPTCR_CLKSOURCE_32 | GPTCR_TEN;
+#endif
+ __raw_writel(i, &cur_gpt->control);
+
+ return 0;
+}
+
+unsigned long timer_read_counter(void)
+{
+ return __raw_readl(&cur_gpt->counter); /* current tick value */
+}
+
+/*
+ * This function is derived from PowerPC code (timebase clock frequency).
+ * On ARM it returns the number of timer ticks per second.
+ */
+ulong get_tbclk(void)
+{
+ return gpt_get_clk();
+}
+
+/*
+ * This function is intended for SHORT delays only.
+ * It will overflow at around 10 seconds @ 400MHz,
+ * or 20 seconds @ 200MHz.
+ */
+unsigned long usec2ticks(unsigned long _usec)
+{
+ unsigned long long usec = _usec;
+
+ usec *= get_tbclk();
+ usec += 999999;
+ do_div(usec, 1000000);
+
+ return usec;
+}