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/mach-at91/arm920t/Makefile

@@ -0,0 +1,13 @@
+#
+# (C) Copyright 2000-2006
+# Wolfgang Denk, DENX Software Engineering, wd@denx.de.
+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+obj-y	+= lowlevel_init.o
+obj-y	+= reset.o
+obj-y	+= timer.o
+obj-y	+= clock.o
+obj-y	+= cpu.o
+obj-y	+= at91rm9200_devices.o

u-boot/arch/arm/mach-at91/arm920t/at91rm9200_devices.c

@@ -0,0 +1,61 @@
+/*
+ * [partely copied from arch/arm/cpu/arm926ejs/at91/arm9260_devices.c]
+ *
+ * (C) Copyright 2011
+ * Andreas Bießmann <andreas@biessmann.org>
+ *
+ * (C) Copyright 2007-2008
+ * Stelian Pop <stelian@popies.net>
+ * Lead Tech Design <www.leadtechdesign.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <asm/arch/at91_common.h>
+#include <asm/arch/clk.h>
+#include <asm/arch/gpio.h>
+
+/*
+ * if CONFIG_AT91_GPIO_PULLUP ist set, keep pullups on on all
+ * peripheral pins. Good to have if hardware is soldered optionally
+ * or in case of SPI no slave is selected. Avoid lines to float
+ * needlessly. Use a short local PUP define.
+ *
+ * Due to errata "TXD floats when CTS is inactive" pullups are always
+ * on for TXD pins.
+ */
+#ifdef CONFIG_AT91_GPIO_PULLUP
+# define PUP CONFIG_AT91_GPIO_PULLUP
+#else
+# define PUP 0
+#endif
+
+void at91_serial0_hw_init(void)
+{
+	at91_set_a_periph(AT91_PIO_PORTA, 17, 1);		/* TXD0 */
+	at91_set_a_periph(AT91_PIO_PORTA, 18, PUP);		/* RXD0 */
+	at91_periph_clk_enable(ATMEL_ID_USART0);
+}
+
+void at91_serial1_hw_init(void)
+{
+	at91_set_a_periph(AT91_PIO_PORTB, 20, PUP);		/* RXD1 */
+	at91_set_a_periph(AT91_PIO_PORTB, 21, 1);		/* TXD1 */
+	at91_periph_clk_enable(ATMEL_ID_USART1);
+}
+
+void at91_serial2_hw_init(void)
+{
+	at91_set_a_periph(AT91_PIO_PORTA, 22, PUP);		/* RXD2 */
+	at91_set_a_periph(AT91_PIO_PORTA, 23, 1);		/* TXD2 */
+	at91_periph_clk_enable(ATMEL_ID_USART2);
+}
+
+void at91_seriald_hw_init(void)
+{
+	at91_set_a_periph(AT91_PIO_PORTA, 30, PUP);		/* DRXD */
+	at91_set_a_periph(AT91_PIO_PORTA, 31, 1);		/* DTXD */
+	/* writing SYS to PCER has no effect on AT91RM9200 */
+}

u-boot/arch/arm/mach-at91/arm920t/clock.c

@@ -0,0 +1,195 @@
+/*
+ * [origin: Linux kernel linux/arch/arm/mach-at91/clock.c]
+ *
+ * Copyright (C) 2011 Andreas Bießmann
+ * Copyright (C) 2005 David Brownell
+ * Copyright (C) 2005 Ivan Kokshaysky
+ * Copyright (C) 2009 Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+#include <common.h>
+#include <asm/io.h>
+#include <asm/arch/hardware.h>
+#include <asm/arch/at91_pmc.h>
+#include <asm/arch/clk.h>
+
+#if !defined(CONFIG_AT91FAMILY)
+# error You need to define CONFIG_AT91FAMILY in your board config!
+#endif
+
+#define EN_PLLB_TIMEOUT	500
+
+DECLARE_GLOBAL_DATA_PTR;
+
+static unsigned long at91_css_to_rate(unsigned long css)
+{
+	switch (css) {
+	case AT91_PMC_MCKR_CSS_SLOW:
+		return CONFIG_SYS_AT91_SLOW_CLOCK;
+	case AT91_PMC_MCKR_CSS_MAIN:
+		return gd->arch.main_clk_rate_hz;
+	case AT91_PMC_MCKR_CSS_PLLA:
+		return gd->arch.plla_rate_hz;
+	case AT91_PMC_MCKR_CSS_PLLB:
+		return gd->arch.pllb_rate_hz;
+	}
+
+	return 0;
+}
+
+#ifdef CONFIG_USB_ATMEL
+static unsigned at91_pll_calc(unsigned main_freq, unsigned out_freq)
+{
+	unsigned i, div = 0, mul = 0, diff = 1 << 30;
+	unsigned ret = (out_freq > 155000000) ? 0xbe00 : 0x3e00;
+
+	/* PLL output max 240 MHz (or 180 MHz per errata) */
+	if (out_freq > 240000000)
+		goto fail;
+
+	for (i = 1; i < 256; i++) {
+		int diff1;
+		unsigned input, mul1;
+
+		/*
+		 * PLL input between 1MHz and 32MHz per spec, but lower
+		 * frequences seem necessary in some cases so allow 100K.
+		 * Warning: some newer products need 2MHz min.
+		 */
+		input = main_freq / i;
+		if (input < 100000)
+			continue;
+		if (input > 32000000)
+			continue;
+
+		mul1 = out_freq / input;
+		if (mul1 > 2048)
+			continue;
+		if (mul1 < 2)
+			goto fail;
+
+		diff1 = out_freq - input * mul1;
+		if (diff1 < 0)
+			diff1 = -diff1;
+		if (diff > diff1) {
+			diff = diff1;
+			div = i;
+			mul = mul1;
+			if (diff == 0)
+				break;
+		}
+	}
+	if (i == 256 && diff > (out_freq >> 5))
+		goto fail;
+	return ret | ((mul - 1) << 16) | div;
+fail:
+	return 0;
+}
+#endif
+
+static u32 at91_pll_rate(u32 freq, u32 reg)
+{
+	unsigned mul, div;
+
+	div = reg & 0xff;
+	mul = (reg >> 16) & 0x7ff;
+	if (div && mul) {
+		freq /= div;
+		freq *= mul + 1;
+	} else
+		freq = 0;
+
+	return freq;
+}
+
+int at91_clock_init(unsigned long main_clock)
+{
+	unsigned freq, mckr;
+	at91_pmc_t *pmc = (at91_pmc_t *) ATMEL_BASE_PMC;
+#ifndef CONFIG_SYS_AT91_MAIN_CLOCK
+	unsigned tmp;
+	/*
+	 * When the bootloader initialized the main oscillator correctly,
+	 * there's no problem using the cycle counter.  But if it didn't,
+	 * or when using oscillator bypass mode, we must be told the speed
+	 * of the main clock.
+	 */
+	if (!main_clock) {
+		do {
+			tmp = readl(&pmc->mcfr);
+		} while (!(tmp & AT91_PMC_MCFR_MAINRDY));
+		tmp &= AT91_PMC_MCFR_MAINF_MASK;
+		main_clock = tmp * (CONFIG_SYS_AT91_SLOW_CLOCK / 16);
+	}
+#endif
+	gd->arch.main_clk_rate_hz = main_clock;
+
+	/* report if PLLA is more than mildly overclocked */
+	gd->arch.plla_rate_hz = at91_pll_rate(main_clock, readl(&pmc->pllar));
+
+#ifdef CONFIG_USB_ATMEL
+	/*
+	 * USB clock init:  choose 48 MHz PLLB value,
+	 * disable 48MHz clock during usb peripheral suspend.
+	 *
+	 * REVISIT:  assumes MCK doesn't derive from PLLB!
+	 */
+	gd->arch.at91_pllb_usb_init = at91_pll_calc(main_clock, 48000000 * 2) |
+			     AT91_PMC_PLLBR_USBDIV_2;
+	gd->arch.pllb_rate_hz = at91_pll_rate(main_clock,
+					      gd->arch.at91_pllb_usb_init);
+#endif
+
+	/*
+	 * MCK and CPU derive from one of those primary clocks.
+	 * For now, assume this parentage won't change.
+	 */
+	mckr = readl(&pmc->mckr);
+	gd->arch.mck_rate_hz = at91_css_to_rate(mckr & AT91_PMC_MCKR_CSS_MASK);
+	freq = gd->arch.mck_rate_hz;
+
+	freq /= (1 << ((mckr & AT91_PMC_MCKR_PRES_MASK) >> 2));	/* prescale */
+	/* mdiv */
+	gd->arch.mck_rate_hz = freq /
+			(1 + ((mckr & AT91_PMC_MCKR_MDIV_MASK) >> 8));
+	gd->arch.cpu_clk_rate_hz = freq;
+
+	return 0;
+}
+
+int at91_pllb_clk_enable(u32 pllbr)
+{
+	struct at91_pmc *pmc = (at91_pmc_t *)ATMEL_BASE_PMC;
+	ulong start_time, tmp_time;
+
+	start_time = get_timer(0);
+	writel(pllbr, &pmc->pllbr);
+	while ((readl(&pmc->sr) & AT91_PMC_LOCKB) != AT91_PMC_LOCKB) {
+		tmp_time = get_timer(0);
+		if ((tmp_time - start_time) > EN_PLLB_TIMEOUT) {
+			printf("ERROR: failed to enable PLLB\n");
+			return -1;
+		}
+	}
+
+	return 0;
+}
+
+int at91_pllb_clk_disable(void)
+{
+	struct at91_pmc *pmc = (at91_pmc_t *)ATMEL_BASE_PMC;
+	ulong start_time, tmp_time;
+
+	start_time = get_timer(0);
+	writel(0, &pmc->pllbr);
+	while ((readl(&pmc->sr) & AT91_PMC_LOCKB) != 0) {
+		tmp_time = get_timer(0);
+		if ((tmp_time - start_time) > EN_PLLB_TIMEOUT) {
+			printf("ERROR: failed to disable PLLB\n");
+			return -1;
+		}
+	}
+
+	return 0;
+}

u-boot/arch/arm/mach-at91/arm920t/cpu.c

@@ -0,0 +1,26 @@
+/*
+ * [origin: arch/arm/cpu/arm926ejs/at91/cpu.c]
+ *
+ * (C) Copyright 2011
+ * Andreas Bießmann, andreas@biessmann.org
+ * (C) Copyright 2010
+ * Reinhard Meyer, reinhard.meyer@emk-elektronik.de
+ * (C) Copyright 2009
+ * Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <asm/arch/hardware.h>
+#include <asm/arch/clk.h>
+
+#ifndef CONFIG_SYS_AT91_MAIN_CLOCK
+#define CONFIG_SYS_AT91_MAIN_CLOCK 0
+#endif
+
+int arch_cpu_init(void)
+{
+	return at91_clock_init(CONFIG_SYS_AT91_MAIN_CLOCK);
+}

u-boot/arch/arm/mach-at91/arm920t/lowlevel_init.S

@@ -0,0 +1,152 @@
+/*
+ * Copyright (C) 1999 2000 2001 Erik Mouw (J.A.K.Mouw@its.tudelft.nl) and
+ *		       Jan-Derk Bakker (J.D.Bakker@its.tudelft.nl)
+ *
+ * Modified for the at91rm9200dk board by
+ * (C) Copyright 2004
+ * Gary Jennejohn, DENX Software Engineering, <garyj@denx.de>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <config.h>
+
+#ifndef CONFIG_SKIP_LOWLEVEL_INIT
+
+#include <asm/arch/hardware.h>
+#include <asm/arch/at91_mc.h>
+#include <asm/arch/at91_pmc.h>
+#include <asm/arch/at91_pio.h>
+
+#define ARM920T_CONTROL	0xC0000000	/* @ set bit 31 (iA) and 30 (nF) */
+
+_MTEXT_BASE:
+#undef START_FROM_MEM
+#ifdef START_FROM_MEM
+	.word	CONFIG_SYS_TEXT_BASE-PHYS_FLASH_1
+#else
+	.word	CONFIG_SYS_TEXT_BASE
+#endif
+
+.globl lowlevel_init
+lowlevel_init:
+	ldr     r1, =AT91_ASM_PMC_MOR
+	/* Main oscillator Enable register */
+#ifdef CONFIG_SYS_USE_MAIN_OSCILLATOR
+	ldr     r0, =0x0000FF01		/* Enable main oscillator */
+#else
+	ldr     r0, =0x0000FF00		/* Disable main oscillator */
+#endif
+	str     r0, [r1] /*AT91C_CKGR_MOR] */
+	/* Add loop to compensate Main Oscillator startup time */
+	ldr     r0, =0x00000010
+LoopOsc:
+	subs    r0, r0, #1
+	bhi     LoopOsc
+
+	/* memory control configuration */
+	/* this isn't very elegant, but	 what the heck */
+	ldr	r0, =SMRDATA
+	ldr	r1, _MTEXT_BASE
+	sub	r0, r0, r1
+	ldr	r2, =SMRDATAE
+	sub	r2, r2, r1
+pllloop:
+	/* the address */
+	ldr	r1, [r0], #4
+	/* the value */
+	ldr	r3, [r0], #4
+	str	r3, [r1]
+	cmp	r2, r0
+	bne	pllloop
+	/* delay - this is all done by guess */
+	ldr	r0, =0x00010000
+	/* (vs reading PMC_SR for LOCKA, LOCKB ... or MOSCS earlier) */
+lock:
+	subs	r0, r0, #1
+	bhi	lock
+	ldr	r0, =SMRDATA1
+	ldr	r1, _MTEXT_BASE
+	sub	r0, r0, r1
+	ldr	r2, =SMRDATA1E
+	sub	r2, r2, r1
+sdinit:
+	/* the address */
+	ldr	r1, [r0], #4
+	/* the value */
+	ldr	r3, [r0], #4
+	str	r3, [r1]
+	cmp	r2, r0
+	bne	sdinit
+
+	/* switch from FastBus to Asynchronous clock mode */
+	mrc	p15, 0, r0, c1, c0, 0
+	orr	r0, r0, #ARM920T_CONTROL
+	mcr	p15, 0, r0, c1, c0, 0
+
+	/* everything is fine now */
+	mov	pc, lr
+
+	.ltorg
+
+SMRDATA:
+	.word AT91_ASM_MC_EBI_CFG
+	.word CONFIG_SYS_EBI_CFGR_VAL
+	.word AT91_ASM_MC_SMC_CSR0
+	.word CONFIG_SYS_SMC_CSR0_VAL
+	.word AT91_ASM_PMC_PLLAR
+	.word CONFIG_SYS_PLLAR_VAL
+	.word AT91_ASM_PMC_PLLBR
+	.word CONFIG_SYS_PLLBR_VAL
+	.word AT91_ASM_PMC_MCKR
+	.word CONFIG_SYS_MCKR_VAL
+SMRDATAE:
+	/* here there's a delay */
+SMRDATA1:
+	.word AT91_ASM_PIOC_ASR
+	.word CONFIG_SYS_PIOC_ASR_VAL
+	.word AT91_ASM_PIOC_BSR
+	.word CONFIG_SYS_PIOC_BSR_VAL
+	.word AT91_ASM_PIOC_PDR
+	.word CONFIG_SYS_PIOC_PDR_VAL
+	.word AT91_ASM_MC_EBI_CSA
+	.word CONFIG_SYS_EBI_CSA_VAL
+	.word AT91_ASM_MC_SDRAMC_CR
+	.word CONFIG_SYS_SDRC_CR_VAL
+	.word AT91_ASM_MC_SDRAMC_MR
+	.word CONFIG_SYS_SDRC_MR_VAL
+	.word CONFIG_SYS_SDRAM
+	.word CONFIG_SYS_SDRAM_VAL
+	.word AT91_ASM_MC_SDRAMC_MR
+	.word CONFIG_SYS_SDRC_MR_VAL1
+	.word CONFIG_SYS_SDRAM
+	.word CONFIG_SYS_SDRAM_VAL
+	.word CONFIG_SYS_SDRAM
+	.word CONFIG_SYS_SDRAM_VAL
+	.word CONFIG_SYS_SDRAM
+	.word CONFIG_SYS_SDRAM_VAL
+	.word CONFIG_SYS_SDRAM
+	.word CONFIG_SYS_SDRAM_VAL
+	.word CONFIG_SYS_SDRAM
+	.word CONFIG_SYS_SDRAM_VAL
+	.word CONFIG_SYS_SDRAM
+	.word CONFIG_SYS_SDRAM_VAL
+	.word CONFIG_SYS_SDRAM
+	.word CONFIG_SYS_SDRAM_VAL
+	.word CONFIG_SYS_SDRAM
+	.word CONFIG_SYS_SDRAM_VAL
+	.word AT91_ASM_MC_SDRAMC_MR
+	.word CONFIG_SYS_SDRC_MR_VAL2
+	.word CONFIG_SYS_SDRAM1
+	.word CONFIG_SYS_SDRAM_VAL
+	.word AT91_ASM_MC_SDRAMC_TR
+	.word CONFIG_SYS_SDRC_TR_VAL
+	.word CONFIG_SYS_SDRAM
+	.word CONFIG_SYS_SDRAM_VAL
+	.word AT91_ASM_MC_SDRAMC_MR
+	.word CONFIG_SYS_SDRC_MR_VAL3
+	.word CONFIG_SYS_SDRAM
+	.word CONFIG_SYS_SDRAM_VAL
+SMRDATA1E:
+	/* SMRDATA1 is 176 bytes long */
+#endif /* CONFIG_SKIP_LOWLEVEL_INIT */

u-boot/arch/arm/mach-at91/arm920t/reset.c

@@ -0,0 +1,41 @@
+/*
+ * (C) Copyright 2002
+ * Lineo, Inc. <www.lineo.com>
+ * Bernhard Kuhn <bkuhn@lineo.com>
+ *
+ * (C) Copyright 2002
+ * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
+ * Marius Groeger <mgroeger@sysgo.de>
+ *
+ * (C) Copyright 2002
+ * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
+ * Alex Zuepke <azu@sysgo.de>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <asm/arch/hardware.h>
+#include <asm/arch/at91_st.h>
+
+void  __attribute__((weak)) board_reset(void)
+{
+	/* true empty function for defining weak symbol */
+}
+
+void reset_cpu(ulong ignored)
+{
+	at91_st_t *st = (at91_st_t *) ATMEL_BASE_ST;
+
+	board_reset();
+
+	/* Reset the cpu by setting up the watchdog timer */
+	writel(AT91_ST_WDMR_RSTEN | AT91_ST_WDMR_EXTEN | AT91_ST_WDMR_WDV(2),
+		&st->wdmr);
+	writel(AT91_ST_CR_WDRST, &st->cr);
+	/* and let it timeout */
+	while (1)
+		;
+	/* Never reached */
+}

u-boot/arch/arm/mach-at91/arm920t/timer.c

@@ -0,0 +1,125 @@
+/*
+ * (C) Copyright 2002
+ * Lineo, Inc. <www.lineo.com>
+ * Bernhard Kuhn <bkuhn@lineo.com>
+ *
+ * (C) Copyright 2002
+ * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
+ * Marius Groeger <mgroeger@sysgo.de>
+ *
+ * (C) Copyright 2002
+ * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
+ * Alex Zuepke <azu@sysgo.de>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+
+#include <asm/io.h>
+#include <asm/arch/hardware.h>
+#include <asm/arch/at91_tc.h>
+#include <asm/arch/clk.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/* the number of clocks per CONFIG_SYS_HZ */
+#define TIMER_LOAD_VAL (CONFIG_SYS_HZ_CLOCK/CONFIG_SYS_HZ)
+
+int timer_init(void)
+{
+	at91_tc_t *tc = (at91_tc_t *) ATMEL_BASE_TC;
+
+	at91_periph_clk_enable(ATMEL_ID_TC0);
+
+	writel(0, &tc->bcr);
+	writel(AT91_TC_BMR_TC0XC0S_NONE | AT91_TC_BMR_TC1XC1S_NONE |
+		AT91_TC_BMR_TC2XC2S_NONE , &tc->bmr);
+
+	writel(AT91_TC_CCR_CLKDIS, &tc->tc[0].ccr);
+	/* set to MCLK/2 and restart the timer
+	when the value in TC_RC is reached */
+	writel(AT91_TC_CMR_TCCLKS_CLOCK1 | AT91_TC_CMR_CPCTRG, &tc->tc[0].cmr);
+
+	writel(0xFFFFFFFF, &tc->tc[0].idr); /* disable interrupts */
+	writel(TIMER_LOAD_VAL, &tc->tc[0].rc);
+
+	writel(AT91_TC_CCR_SWTRG | AT91_TC_CCR_CLKEN, &tc->tc[0].ccr);
+	gd->arch.lastinc = 0;
+	gd->arch.tbl = 0;
+
+	return 0;
+}
+
+/*
+ * timer without interrupts
+ */
+ulong get_timer(ulong base)
+{
+	return get_timer_masked() - base;
+}
+
+void __udelay(unsigned long usec)
+{
+	udelay_masked(usec);
+}
+
+ulong get_timer_raw(void)
+{
+	at91_tc_t *tc = (at91_tc_t *) ATMEL_BASE_TC;
+	u32 now;
+
+	now = readl(&tc->tc[0].cv) & 0x0000ffff;
+
+	if (now >= gd->arch.lastinc) {
+		/* normal mode */
+		gd->arch.tbl += now - gd->arch.lastinc;
+	} else {
+		/* we have an overflow ... */
+		gd->arch.tbl += now + TIMER_LOAD_VAL - gd->arch.lastinc;
+	}
+	gd->arch.lastinc = now;
+
+	return gd->arch.tbl;
+}
+
+ulong get_timer_masked(void)
+{
+	return get_timer_raw()/TIMER_LOAD_VAL;
+}
+
+void udelay_masked(unsigned long usec)
+{
+	u32 tmo;
+	u32 endtime;
+	signed long diff;
+
+	tmo = CONFIG_SYS_HZ_CLOCK / 1000;
+	tmo *= usec;
+	tmo /= 1000;
+
+	endtime = get_timer_raw() + tmo;
+
+	do {
+		u32 now = get_timer_raw();
+		diff = endtime - now;
+	} while (diff >= 0);
+}
+
+/*
+ * This function is derived from PowerPC code (read timebase as long long).
+ * On ARM it just returns the timer value.
+ */
+unsigned long long get_ticks(void)
+{
+	return get_timer(0);
+}
+
+/*
+ * 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 CONFIG_SYS_HZ;
+}