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/board/freescale/bsc9131rdb/spl_minimal.c

@@ -0,0 +1,104 @@
+/*
+ * Copyright 2013 Freescale Semiconductor, Inc.
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <ns16550.h>
+#include <asm/io.h>
+#include <nand.h>
+#include <linux/compiler.h>
+#include <asm/fsl_law.h>
+#include <fsl_ddr_sdram.h>
+#include <asm/global_data.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/*
+ * Fixed sdram init -- doesn't use serial presence detect.
+ */
+static void sdram_init(void)
+{
+	struct ccsr_ddr __iomem *ddr =
+		(struct ccsr_ddr __iomem *)CONFIG_SYS_FSL_DDR_ADDR;
+
+	__raw_writel(CONFIG_SYS_DDR_CS0_BNDS, &ddr->cs0_bnds);
+	__raw_writel(CONFIG_SYS_DDR_CS0_CONFIG, &ddr->cs0_config);
+#if CONFIG_CHIP_SELECTS_PER_CTRL > 1
+	__raw_writel(CONFIG_SYS_DDR_CS1_BNDS, &ddr->cs1_bnds);
+	__raw_writel(CONFIG_SYS_DDR_CS1_CONFIG, &ddr->cs1_config);
+#endif
+	__raw_writel(CONFIG_SYS_DDR_TIMING_3_800, &ddr->timing_cfg_3);
+	__raw_writel(CONFIG_SYS_DDR_TIMING_0_800, &ddr->timing_cfg_0);
+	__raw_writel(CONFIG_SYS_DDR_TIMING_1_800, &ddr->timing_cfg_1);
+	__raw_writel(CONFIG_SYS_DDR_TIMING_2_800, &ddr->timing_cfg_2);
+
+	__raw_writel(CONFIG_SYS_DDR_CONTROL_2, &ddr->sdram_cfg_2);
+	__raw_writel(CONFIG_SYS_DDR_MODE_1_800, &ddr->sdram_mode);
+	__raw_writel(CONFIG_SYS_DDR_MODE_2_800, &ddr->sdram_mode_2);
+
+	__raw_writel(CONFIG_SYS_DDR_INTERVAL_800, &ddr->sdram_interval);
+	__raw_writel(CONFIG_SYS_DDR_DATA_INIT, &ddr->sdram_data_init);
+	__raw_writel(CONFIG_SYS_DDR_CLK_CTRL_800, &ddr->sdram_clk_cntl);
+
+	__raw_writel(CONFIG_SYS_DDR_WRLVL_CONTROL_800, &ddr->ddr_wrlvl_cntl);
+	__raw_writel(CONFIG_SYS_DDR_TIMING_4, &ddr->timing_cfg_4);
+	__raw_writel(CONFIG_SYS_DDR_TIMING_5, &ddr->timing_cfg_5);
+	__raw_writel(CONFIG_SYS_DDR_ZQ_CONTROL, &ddr->ddr_zq_cntl);
+
+	/* Set, but do not enable the memory */
+	__raw_writel(CONFIG_SYS_DDR_CONTROL & ~SDRAM_CFG_MEM_EN, &ddr->sdram_cfg);
+
+	asm volatile("sync;isync");
+	udelay(500);
+
+	/* Let the controller go */
+	out_be32(&ddr->sdram_cfg, in_be32(&ddr->sdram_cfg) | SDRAM_CFG_MEM_EN);
+
+	set_next_law(CONFIG_SYS_NAND_DDR_LAW, LAW_SIZE_1G, LAW_TRGT_IF_DDR_1);
+}
+
+void board_init_f(ulong bootflag)
+{
+	u32 plat_ratio;
+	ccsr_gur_t *gur = (void *)CONFIG_SYS_MPC85xx_GUTS_ADDR;
+
+	/* initialize selected port with appropriate baud rate */
+	plat_ratio = in_be32(&gur->porpllsr) & MPC85xx_PORPLLSR_PLAT_RATIO;
+	plat_ratio >>= 1;
+	gd->bus_clk = CONFIG_SYS_CLK_FREQ * plat_ratio;
+
+	NS16550_init((NS16550_t)CONFIG_SYS_NS16550_COM1,
+		     gd->bus_clk / 16 / CONFIG_BAUDRATE);
+
+	puts("\nNAND boot... ");
+
+	/* Initialize the DDR3 */
+	sdram_init();
+
+	/* copy code to RAM and jump to it - this should not return */
+	/* NOTE - code has to be copied out of NAND buffer before
+	 * other blocks can be read.
+	 */
+	relocate_code(CONFIG_SPL_RELOC_STACK, 0, CONFIG_SPL_RELOC_TEXT_BASE);
+}
+
+void board_init_r(gd_t *gd, ulong dest_addr)
+{
+	nand_boot();
+}
+
+void putc(char c)
+{
+	if (c == '\n')
+		NS16550_putc((NS16550_t)CONFIG_SYS_NS16550_COM1, '\r');
+
+	NS16550_putc((NS16550_t)CONFIG_SYS_NS16550_COM1, c);
+}
+
+void puts(const char *str)
+{
+	while (*str)
+		putc(*str++);
+}