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/mips/mach-ath79/qca953x/clk.c

@@ -0,0 +1,111 @@
+/*
+ * Copyright (C) 2015-2016 Wills Wang <wills.wang@live.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <asm/addrspace.h>
+#include <asm/types.h>
+#include <mach/ar71xx_regs.h>
+#include <mach/ath79.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+static u32 qca953x_get_xtal(void)
+{
+	u32 val;
+
+	val = ath79_get_bootstrap();
+	if (val & QCA953X_BOOTSTRAP_REF_CLK_40)
+		return 40000000;
+	else
+		return 25000000;
+}
+
+int get_serial_clock(void)
+{
+	return qca953x_get_xtal();
+}
+
+int get_clocks(void)
+{
+	void __iomem *regs;
+	u32 val, ctrl, xtal, pll, div;
+
+	regs = map_physmem(AR71XX_PLL_BASE, AR71XX_PLL_SIZE,
+			   MAP_NOCACHE);
+
+	xtal = qca953x_get_xtal();
+	ctrl = readl(regs + QCA953X_PLL_CLK_CTRL_REG);
+	val = readl(regs + QCA953X_PLL_CPU_CONFIG_REG);
+
+	/* VCOOUT = XTAL * DIV_INT */
+	div = (val >> QCA953X_PLL_CPU_CONFIG_REFDIV_SHIFT)
+			& QCA953X_PLL_CPU_CONFIG_REFDIV_MASK;
+	pll = xtal / div;
+
+	/* PLLOUT = VCOOUT * (1/2^OUTDIV) */
+	div = (val >> QCA953X_PLL_CPU_CONFIG_NINT_SHIFT)
+			& QCA953X_PLL_CPU_CONFIG_NINT_MASK;
+	pll *= div;
+	div = (val >> QCA953X_PLL_CPU_CONFIG_OUTDIV_SHIFT)
+			& QCA953X_PLL_CPU_CONFIG_OUTDIV_MASK;
+	if (!div)
+		div = 1;
+	pll >>= div;
+
+	/* CPU_CLK = PLLOUT / CPU_POST_DIV */
+	div = ((ctrl >> QCA953X_PLL_CLK_CTRL_CPU_POST_DIV_SHIFT)
+			& QCA953X_PLL_CLK_CTRL_CPU_POST_DIV_MASK) + 1;
+	gd->cpu_clk = pll / div;
+
+
+	val = readl(regs + QCA953X_PLL_DDR_CONFIG_REG);
+	/* VCOOUT = XTAL * DIV_INT */
+	div = (val >> QCA953X_PLL_DDR_CONFIG_REFDIV_SHIFT)
+			& QCA953X_PLL_DDR_CONFIG_REFDIV_MASK;
+	pll = xtal / div;
+
+	/* PLLOUT = VCOOUT * (1/2^OUTDIV) */
+	div = (val >> QCA953X_PLL_DDR_CONFIG_NINT_SHIFT)
+			& QCA953X_PLL_DDR_CONFIG_NINT_MASK;
+	pll *= div;
+	div = (val >> QCA953X_PLL_DDR_CONFIG_OUTDIV_SHIFT)
+			& QCA953X_PLL_DDR_CONFIG_OUTDIV_MASK;
+	if (!div)
+		div = 1;
+	pll >>= div;
+
+	/* DDR_CLK = PLLOUT / DDR_POST_DIV */
+	div = ((ctrl >> QCA953X_PLL_CLK_CTRL_DDR_POST_DIV_SHIFT)
+			& QCA953X_PLL_CLK_CTRL_DDR_POST_DIV_MASK) + 1;
+	gd->mem_clk = pll / div;
+
+	div = ((ctrl >> QCA953X_PLL_CLK_CTRL_AHB_POST_DIV_SHIFT)
+			& QCA953X_PLL_CLK_CTRL_AHB_POST_DIV_MASK) + 1;
+	if (ctrl & QCA953X_PLL_CLK_CTRL_AHBCLK_FROM_DDRPLL) {
+		/* AHB_CLK = DDR_CLK / AHB_POST_DIV */
+		gd->bus_clk = gd->mem_clk / (div + 1);
+	} else {
+		/* AHB_CLK = CPU_CLK / AHB_POST_DIV */
+		gd->bus_clk = gd->cpu_clk / (div + 1);
+	}
+
+	return 0;
+}
+
+ulong get_bus_freq(ulong dummy)
+{
+	if (!gd->bus_clk)
+		get_clocks();
+	return gd->bus_clk;
+}
+
+ulong get_ddr_freq(ulong dummy)
+{
+	if (!gd->mem_clk)
+		get_clocks();
+	return gd->mem_clk;
+}