avionic design with actual uboot and tooling

submodule of avionic design uboot bootloader and with included tools to
get you started , read readme.md and readme-tk1-loader.md

u-boot/arch/arm/imx-common/timer.c

@@ -0,0 +1,121 @@
+/*
+ * (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())
+		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, set 24Mhz OSC Enable bit and prescaler */
+		if (is_mx6sdl() || is_mx6sx() || is_mx6ul()) {
+			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);
+
+	gd->arch.tbl = __raw_readl(&cur_gpt->counter);
+	gd->arch.tbu = 0;
+
+	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();
+}