GK SDK 源码库: XMIPCLinuxV100R005C00SPC030 (kernel/tools/open_source excluded)

source/bootloader/u-boot-2020.01/arch/arm/cpu/arm926ejs/mxs/Makefile

@@ -0,0 +1,81 @@
+# SPDX-License-Identifier: GPL-2.0+
+#
+# (C) Copyright 2000-2006
+# Wolfgang Denk, DENX Software Engineering, wd@denx.de.
+
+extra-$(CONFIG_SPL_BUILD) := start.o
+
+obj-y	= clock.o mxs.o iomux.o timer.o
+
+ifdef	CONFIG_SPL_BUILD
+obj-y	+= spl_boot.o spl_lradc_init.o spl_mem_init.o spl_power_init.o
+endif
+
+# Specify the target for use in elftosb call
+MKIMAGE_TARGET-$(CONFIG_MX23) = mxsimage$(CONFIG_SPL_FRAMEWORK:%=-spl).mx23.cfg
+MKIMAGE_TARGET-$(CONFIG_MX28) = mxsimage$(CONFIG_SPL_FRAMEWORK:%=-spl).mx28.cfg
+
+# Generate HAB-capable IVT
+#
+# Note on computing the post-IVT size field value for the U-Boot binary.
+# The value is the result of adding the following:
+#  -> The size of U-Boot binary aligned to 64B (u-boot.bin)
+#  -> The size of IVT block aligned to 64B (u-boot.ivt)
+#  -> The size of U-Boot signature (u-boot.sig), 3904 B
+#  -> The 64B hole in front of U-Boot binary for 'struct mxs_spl_data' passing
+#
+quiet_cmd_mkivt_mxs = MXSIVT  $@
+cmd_mkivt_mxs =								\
+	sz=`expr \`stat -c "%s" $^\` + 64 + 3904 + 128` ;		\
+	echo -n "0x402000d1 $2 0 0 0 $3 $4 0 $$sz 0 0 0 0 0 0 0" |	\
+	tr -s " " | xargs -d " " -i printf "%08x\n" "{}" | rev |	\
+	sed "s/\(.\)\(.\)/\\\\\\\\x\2\1\n/g" | xargs -i printf "{}" >$@
+
+# Align binary to 64B
+quiet_cmd_mkalign_mxs = MXSALGN $@
+cmd_mkalign_mxs =							\
+	dd if=$^ of=$@ ibs=64 conv=sync 2>/dev/null &&			\
+	mv $@ $^
+
+# Assemble the CSF file
+quiet_cmd_mkcsfreq_mxs = MXSCSFR $@
+cmd_mkcsfreq_mxs =							\
+	ivt=$(word 1,$^) ;						\
+	bin=$(word 2,$^) ;						\
+	csf=$(word 3,$^) ;						\
+	sed "s@VENDOR@$(VENDOR)@g;s@BOARD@$(BOARD)@g" "$$csf" |		\
+		sed '/^\#\#Blocks/ d' > $@ ;				\
+	echo "  Blocks = $2 0x0 `stat -c '%s' $$bin` \"$$bin\" , \\" >> $@ ; \
+	echo "           $3 0x0 0x40 \"$$ivt\"" >> $@
+
+# Sign files
+quiet_cmd_mkcst_mxs = MXSCST  $@
+cmd_mkcst_mxs = cst -o $@ < $^						\
+	$(if $(KBUILD_VERBOSE:1=), >/dev/null)
+
+spl/u-boot-spl.ivt: spl/u-boot-spl.bin
+	$(call if_changed,mkalign_mxs)
+	$(call if_changed,mkivt_mxs,$(CONFIG_SPL_TEXT_BASE),\
+		0x00008000,0x00008040)
+
+u-boot.ivt: u-boot.bin
+	$(call if_changed,mkalign_mxs)
+	$(call if_changed,mkivt_mxs,$(CONFIG_SYS_TEXT_BASE),\
+		0x40001000,0x40001040)
+
+spl/u-boot-spl.csf: spl/u-boot-spl.ivt spl/u-boot-spl.bin board/$(VENDOR)/$(BOARD)/sign/u-boot-spl.csf
+	$(call if_changed,mkcsfreq_mxs,$(CONFIG_SPL_TEXT_BASE),0x8000)
+
+u-boot.csf: u-boot.ivt u-boot.bin board/$(VENDOR)/$(BOARD)/sign/u-boot.csf
+	$(call if_changed,mkcsfreq_mxs,$(CONFIG_SYS_TEXT_BASE),0x40001000)
+
+%.sig: %.csf
+	$(call if_changed,mkcst_mxs)
+
+MKIMAGEFLAGS_u-boot.sb = -n $< -T mxsimage
+u-boot.sb: $(src)/$(MKIMAGE_TARGET-y) u-boot.bin spl/u-boot-spl.bin FORCE
+	$(call if_changed,mkimage)
+
+MKIMAGEFLAGS_u-boot-signed.sb = -n $< -T mxsimage
+u-boot-signed.sb: $(src)/mxsimage-signed.cfg u-boot.ivt u-boot.sig spl/u-boot-spl.ivt spl/u-boot-spl.sig FORCE
+	$(call if_changed,mkimage)

source/bootloader/u-boot-2020.01/arch/arm/cpu/arm926ejs/mxs/clock.c

@@ -0,0 +1,435 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Freescale i.MX23/i.MX28 clock setup code
+ *
+ * Copyright (C) 2011 Marek Vasut <marek.vasut@gmail.com>
+ * on behalf of DENX Software Engineering GmbH
+ *
+ * Based on code from LTIB:
+ * Copyright (C) 2010 Freescale Semiconductor, Inc.
+ */
+
+#include <common.h>
+#include <linux/errno.h>
+#include <asm/io.h>
+#include <asm/arch/clock.h>
+#include <asm/arch/imx-regs.h>
+
+/*
+ * The PLL frequency is 480MHz and XTAL frequency is 24MHz
+ *   iMX23: datasheet section 4.2
+ *   iMX28: datasheet section 10.2
+ */
+#define	PLL_FREQ_KHZ	480000
+#define	PLL_FREQ_COEF	18
+#define	XTAL_FREQ_KHZ	24000
+
+#define	PLL_FREQ_MHZ	(PLL_FREQ_KHZ / 1000)
+#define	XTAL_FREQ_MHZ	(XTAL_FREQ_KHZ / 1000)
+
+#if defined(CONFIG_MX23)
+#define MXC_SSPCLK_MAX MXC_SSPCLK0
+#elif defined(CONFIG_MX28)
+#define MXC_SSPCLK_MAX MXC_SSPCLK3
+#endif
+
+static uint32_t mxs_get_pclk(void)
+{
+	struct mxs_clkctrl_regs *clkctrl_regs =
+		(struct mxs_clkctrl_regs *)MXS_CLKCTRL_BASE;
+
+	uint32_t clkctrl, clkseq, div;
+	uint8_t clkfrac, frac;
+
+	clkctrl = readl(&clkctrl_regs->hw_clkctrl_cpu);
+
+	/* No support of fractional divider calculation */
+	if (clkctrl &
+		(CLKCTRL_CPU_DIV_XTAL_FRAC_EN | CLKCTRL_CPU_DIV_CPU_FRAC_EN)) {
+		return 0;
+	}
+
+	clkseq = readl(&clkctrl_regs->hw_clkctrl_clkseq);
+
+	/* XTAL Path */
+	if (clkseq & CLKCTRL_CLKSEQ_BYPASS_CPU) {
+		div = (clkctrl & CLKCTRL_CPU_DIV_XTAL_MASK) >>
+			CLKCTRL_CPU_DIV_XTAL_OFFSET;
+		return XTAL_FREQ_MHZ / div;
+	}
+
+	/* REF Path */
+	clkfrac = readb(&clkctrl_regs->hw_clkctrl_frac0[CLKCTRL_FRAC0_CPU]);
+	frac = clkfrac & CLKCTRL_FRAC_FRAC_MASK;
+	div = clkctrl & CLKCTRL_CPU_DIV_CPU_MASK;
+	return (PLL_FREQ_MHZ * PLL_FREQ_COEF / frac) / div;
+}
+
+static uint32_t mxs_get_hclk(void)
+{
+	struct mxs_clkctrl_regs *clkctrl_regs =
+		(struct mxs_clkctrl_regs *)MXS_CLKCTRL_BASE;
+
+	uint32_t div;
+	uint32_t clkctrl;
+
+	clkctrl = readl(&clkctrl_regs->hw_clkctrl_hbus);
+
+	/* No support of fractional divider calculation */
+	if (clkctrl & CLKCTRL_HBUS_DIV_FRAC_EN)
+		return 0;
+
+	div = clkctrl & CLKCTRL_HBUS_DIV_MASK;
+	return mxs_get_pclk() / div;
+}
+
+static uint32_t mxs_get_emiclk(void)
+{
+	struct mxs_clkctrl_regs *clkctrl_regs =
+		(struct mxs_clkctrl_regs *)MXS_CLKCTRL_BASE;
+
+	uint32_t clkctrl, clkseq, div;
+	uint8_t clkfrac, frac;
+
+	clkseq = readl(&clkctrl_regs->hw_clkctrl_clkseq);
+	clkctrl = readl(&clkctrl_regs->hw_clkctrl_emi);
+
+	/* XTAL Path */
+	if (clkseq & CLKCTRL_CLKSEQ_BYPASS_EMI) {
+		div = (clkctrl & CLKCTRL_EMI_DIV_XTAL_MASK) >>
+			CLKCTRL_EMI_DIV_XTAL_OFFSET;
+		return XTAL_FREQ_MHZ / div;
+	}
+
+	/* REF Path */
+	clkfrac = readb(&clkctrl_regs->hw_clkctrl_frac0[CLKCTRL_FRAC0_EMI]);
+	frac = clkfrac & CLKCTRL_FRAC_FRAC_MASK;
+	div = clkctrl & CLKCTRL_EMI_DIV_EMI_MASK;
+	return (PLL_FREQ_MHZ * PLL_FREQ_COEF / frac) / div;
+}
+
+static uint32_t mxs_get_gpmiclk(void)
+{
+	struct mxs_clkctrl_regs *clkctrl_regs =
+		(struct mxs_clkctrl_regs *)MXS_CLKCTRL_BASE;
+#if defined(CONFIG_MX23)
+	uint8_t *reg =
+		&clkctrl_regs->hw_clkctrl_frac0[CLKCTRL_FRAC0_CPU];
+#elif defined(CONFIG_MX28)
+	uint8_t *reg =
+		&clkctrl_regs->hw_clkctrl_frac1[CLKCTRL_FRAC1_GPMI];
+#endif
+	uint32_t clkctrl, clkseq, div;
+	uint8_t clkfrac, frac;
+
+	clkseq = readl(&clkctrl_regs->hw_clkctrl_clkseq);
+	clkctrl = readl(&clkctrl_regs->hw_clkctrl_gpmi);
+
+	/* XTAL Path */
+	if (clkseq & CLKCTRL_CLKSEQ_BYPASS_GPMI) {
+		div = clkctrl & CLKCTRL_GPMI_DIV_MASK;
+		return XTAL_FREQ_MHZ / div;
+	}
+
+	/* REF Path */
+	clkfrac = readb(reg);
+	frac = clkfrac & CLKCTRL_FRAC_FRAC_MASK;
+	div = clkctrl & CLKCTRL_GPMI_DIV_MASK;
+	return (PLL_FREQ_MHZ * PLL_FREQ_COEF / frac) / div;
+}
+
+/*
+ * Set IO clock frequency, in kHz
+ */
+void mxs_set_ioclk(enum mxs_ioclock io, uint32_t freq)
+{
+	struct mxs_clkctrl_regs *clkctrl_regs =
+		(struct mxs_clkctrl_regs *)MXS_CLKCTRL_BASE;
+	uint32_t div;
+	int io_reg;
+
+	if (freq == 0)
+		return;
+
+	if ((io < MXC_IOCLK0) || (io > MXC_IOCLK1))
+		return;
+
+	div = (PLL_FREQ_KHZ * PLL_FREQ_COEF) / freq;
+
+	if (div < 18)
+		div = 18;
+
+	if (div > 35)
+		div = 35;
+
+	io_reg = CLKCTRL_FRAC0_IO0 - io;	/* Register order is reversed */
+	writeb(CLKCTRL_FRAC_CLKGATE,
+		&clkctrl_regs->hw_clkctrl_frac0_set[io_reg]);
+	writeb(CLKCTRL_FRAC_CLKGATE | (div & CLKCTRL_FRAC_FRAC_MASK),
+		&clkctrl_regs->hw_clkctrl_frac0[io_reg]);
+	writeb(CLKCTRL_FRAC_CLKGATE,
+		&clkctrl_regs->hw_clkctrl_frac0_clr[io_reg]);
+}
+
+/*
+ * Get IO clock, returns IO clock in kHz
+ */
+static uint32_t mxs_get_ioclk(enum mxs_ioclock io)
+{
+	struct mxs_clkctrl_regs *clkctrl_regs =
+		(struct mxs_clkctrl_regs *)MXS_CLKCTRL_BASE;
+	uint8_t ret;
+	int io_reg;
+
+	if ((io < MXC_IOCLK0) || (io > MXC_IOCLK1))
+		return 0;
+
+	io_reg = CLKCTRL_FRAC0_IO0 - io;	/* Register order is reversed */
+
+	ret = readb(&clkctrl_regs->hw_clkctrl_frac0[io_reg]) &
+		CLKCTRL_FRAC_FRAC_MASK;
+
+	return (PLL_FREQ_KHZ * PLL_FREQ_COEF) / ret;
+}
+
+/*
+ * Configure SSP clock frequency, in kHz
+ */
+void mxs_set_sspclk(enum mxs_sspclock ssp, uint32_t freq, int xtal)
+{
+	struct mxs_clkctrl_regs *clkctrl_regs =
+		(struct mxs_clkctrl_regs *)MXS_CLKCTRL_BASE;
+	uint32_t clk, clkreg;
+
+	if (ssp > MXC_SSPCLK_MAX)
+		return;
+
+	clkreg = (uint32_t)(&clkctrl_regs->hw_clkctrl_ssp0) +
+			(ssp * sizeof(struct mxs_register_32));
+
+	clrbits_le32(clkreg, CLKCTRL_SSP_CLKGATE);
+	while (readl(clkreg) & CLKCTRL_SSP_CLKGATE)
+		;
+
+	if (xtal)
+		clk = XTAL_FREQ_KHZ;
+	else
+		clk = mxs_get_ioclk(ssp >> 1);
+
+	if (freq > clk)
+		return;
+
+	/* Calculate the divider and cap it if necessary */
+	clk /= freq;
+	if (clk > CLKCTRL_SSP_DIV_MASK)
+		clk = CLKCTRL_SSP_DIV_MASK;
+
+	clrsetbits_le32(clkreg, CLKCTRL_SSP_DIV_MASK, clk);
+	while (readl(clkreg) & CLKCTRL_SSP_BUSY)
+		;
+
+	if (xtal)
+		writel(CLKCTRL_CLKSEQ_BYPASS_SSP0 << ssp,
+			&clkctrl_regs->hw_clkctrl_clkseq_set);
+	else
+		writel(CLKCTRL_CLKSEQ_BYPASS_SSP0 << ssp,
+			&clkctrl_regs->hw_clkctrl_clkseq_clr);
+}
+
+/*
+ * Return SSP frequency, in kHz
+ */
+static uint32_t mxs_get_sspclk(enum mxs_sspclock ssp)
+{
+	struct mxs_clkctrl_regs *clkctrl_regs =
+		(struct mxs_clkctrl_regs *)MXS_CLKCTRL_BASE;
+	uint32_t clkreg;
+	uint32_t clk, tmp;
+
+	if (ssp > MXC_SSPCLK_MAX)
+		return 0;
+
+	tmp = readl(&clkctrl_regs->hw_clkctrl_clkseq);
+	if (tmp & (CLKCTRL_CLKSEQ_BYPASS_SSP0 << ssp))
+		return XTAL_FREQ_KHZ;
+
+	clkreg = (uint32_t)(&clkctrl_regs->hw_clkctrl_ssp0) +
+			(ssp * sizeof(struct mxs_register_32));
+
+	tmp = readl(clkreg) & CLKCTRL_SSP_DIV_MASK;
+
+	if (tmp == 0)
+		return 0;
+
+	clk = mxs_get_ioclk(ssp >> 1);
+
+	return clk / tmp;
+}
+
+/*
+ * Set SSP/MMC bus frequency, in kHz)
+ */
+void mxs_set_ssp_busclock(unsigned int bus, uint32_t freq)
+{
+	struct mxs_ssp_regs *ssp_regs;
+	const enum mxs_sspclock clk = mxs_ssp_clock_by_bus(bus);
+	const uint32_t sspclk = mxs_get_sspclk(clk);
+	uint32_t reg;
+	uint32_t divide, rate, tgtclk;
+
+	ssp_regs = mxs_ssp_regs_by_bus(bus);
+
+	/*
+	 * SSP bit rate = SSPCLK / (CLOCK_DIVIDE * (1 + CLOCK_RATE)),
+	 * CLOCK_DIVIDE has to be an even value from 2 to 254, and
+	 * CLOCK_RATE could be any integer from 0 to 255.
+	 */
+	for (divide = 2; divide < 254; divide += 2) {
+		rate = sspclk / freq / divide;
+		if (rate <= 256)
+			break;
+	}
+
+	tgtclk = sspclk / divide / rate;
+	while (tgtclk > freq) {
+		rate++;
+		tgtclk = sspclk / divide / rate;
+	}
+	if (rate > 256)
+		rate = 256;
+
+	/* Always set timeout the maximum */
+	reg = SSP_TIMING_TIMEOUT_MASK |
+		(divide << SSP_TIMING_CLOCK_DIVIDE_OFFSET) |
+		((rate - 1) << SSP_TIMING_CLOCK_RATE_OFFSET);
+	writel(reg, &ssp_regs->hw_ssp_timing);
+
+	debug("SPI%d: Set freq rate to %d KHz (requested %d KHz)\n",
+		bus, tgtclk, freq);
+}
+
+void mxs_set_lcdclk(uint32_t __maybe_unused lcd_base, uint32_t freq)
+{
+	struct mxs_clkctrl_regs *clkctrl_regs =
+		(struct mxs_clkctrl_regs *)MXS_CLKCTRL_BASE;
+	uint32_t fp, x, k_rest, k_best, x_best, tk;
+	int32_t k_best_l = 999, k_best_t = 0, x_best_l = 0xff, x_best_t = 0xff;
+
+	if (freq == 0)
+		return;
+
+#if defined(CONFIG_MX23)
+	writel(CLKCTRL_CLKSEQ_BYPASS_PIX, &clkctrl_regs->hw_clkctrl_clkseq_clr);
+#elif defined(CONFIG_MX28)
+	writel(CLKCTRL_CLKSEQ_BYPASS_DIS_LCDIF, &clkctrl_regs->hw_clkctrl_clkseq_clr);
+#endif
+
+	/*
+	 *             /               18 \     1       1
+	 * freq kHz = | 480000000 Hz * --  | * --- * ------
+	 *             \                x /     k     1000
+	 *
+	 *      480000000 Hz   18
+	 *      ------------ * --
+	 *        freq kHz      x
+	 * k = -------------------
+	 *             1000
+	 */
+
+	fp = ((PLL_FREQ_KHZ * 1000) / freq) * 18;
+
+	for (x = 18; x <= 35; x++) {
+		tk = fp / x;
+		if ((tk / 1000 == 0) || (tk / 1000 > 255))
+			continue;
+
+		k_rest = tk % 1000;
+
+		if (k_rest < (k_best_l % 1000)) {
+			k_best_l = tk;
+			x_best_l = x;
+		}
+
+		if (k_rest > (k_best_t % 1000)) {
+			k_best_t = tk;
+			x_best_t = x;
+		}
+	}
+
+	if (1000 - (k_best_t % 1000) > (k_best_l % 1000)) {
+		k_best = k_best_l;
+		x_best = x_best_l;
+	} else {
+		k_best = k_best_t;
+		x_best = x_best_t;
+	}
+
+	k_best /= 1000;
+
+#if defined(CONFIG_MX23)
+	writeb(CLKCTRL_FRAC_CLKGATE,
+		&clkctrl_regs->hw_clkctrl_frac0_set[CLKCTRL_FRAC0_PIX]);
+	writeb(CLKCTRL_FRAC_CLKGATE | (x_best & CLKCTRL_FRAC_FRAC_MASK),
+		&clkctrl_regs->hw_clkctrl_frac0[CLKCTRL_FRAC0_PIX]);
+	writeb(CLKCTRL_FRAC_CLKGATE,
+		&clkctrl_regs->hw_clkctrl_frac0_clr[CLKCTRL_FRAC0_PIX]);
+
+	writel(CLKCTRL_PIX_CLKGATE,
+		&clkctrl_regs->hw_clkctrl_pix_set);
+	clrsetbits_le32(&clkctrl_regs->hw_clkctrl_pix,
+			CLKCTRL_PIX_DIV_MASK | CLKCTRL_PIX_CLKGATE,
+			k_best << CLKCTRL_PIX_DIV_OFFSET);
+
+	while (readl(&clkctrl_regs->hw_clkctrl_pix) & CLKCTRL_PIX_BUSY)
+		;
+#elif defined(CONFIG_MX28)
+	writeb(CLKCTRL_FRAC_CLKGATE,
+		&clkctrl_regs->hw_clkctrl_frac1_set[CLKCTRL_FRAC1_PIX]);
+	writeb(CLKCTRL_FRAC_CLKGATE | (x_best & CLKCTRL_FRAC_FRAC_MASK),
+		&clkctrl_regs->hw_clkctrl_frac1[CLKCTRL_FRAC1_PIX]);
+	writeb(CLKCTRL_FRAC_CLKGATE,
+		&clkctrl_regs->hw_clkctrl_frac1_clr[CLKCTRL_FRAC1_PIX]);
+
+	writel(CLKCTRL_DIS_LCDIF_CLKGATE,
+		&clkctrl_regs->hw_clkctrl_lcdif_set);
+	clrsetbits_le32(&clkctrl_regs->hw_clkctrl_lcdif,
+			CLKCTRL_DIS_LCDIF_DIV_MASK | CLKCTRL_DIS_LCDIF_CLKGATE,
+			k_best << CLKCTRL_DIS_LCDIF_DIV_OFFSET);
+
+	while (readl(&clkctrl_regs->hw_clkctrl_lcdif) & CLKCTRL_DIS_LCDIF_BUSY)
+		;
+#endif
+}
+
+uint32_t mxc_get_clock(enum mxc_clock clk)
+{
+	switch (clk) {
+	case MXC_ARM_CLK:
+		return mxs_get_pclk() * 1000000;
+	case MXC_GPMI_CLK:
+		return mxs_get_gpmiclk() * 1000000;
+	case MXC_AHB_CLK:
+	case MXC_IPG_CLK:
+		return mxs_get_hclk() * 1000000;
+	case MXC_EMI_CLK:
+		return mxs_get_emiclk();
+	case MXC_IO0_CLK:
+		return mxs_get_ioclk(MXC_IOCLK0);
+	case MXC_IO1_CLK:
+		return mxs_get_ioclk(MXC_IOCLK1);
+	case MXC_XTAL_CLK:
+		return XTAL_FREQ_KHZ * 1000;
+	case MXC_SSP0_CLK:
+		return mxs_get_sspclk(MXC_SSPCLK0);
+#ifdef CONFIG_MX28
+	case MXC_SSP1_CLK:
+		return mxs_get_sspclk(MXC_SSPCLK1);
+	case MXC_SSP2_CLK:
+		return mxs_get_sspclk(MXC_SSPCLK2);
+	case MXC_SSP3_CLK:
+		return mxs_get_sspclk(MXC_SSPCLK3);
+#endif
+	}
+
+	return 0;
+}

source/bootloader/u-boot-2020.01/arch/arm/cpu/arm926ejs/mxs/iomux.c

@@ -0,0 +1,96 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright 2004-2006,2010 Freescale Semiconductor, Inc. All Rights Reserved.
+ * Copyright (C) 2008 by Sascha Hauer <kernel@pengutronix.de>
+ * Copyright (C) 2009 by Jan Weitzel Phytec Messtechnik GmbH,
+ *                       <armlinux@phytec.de>
+ */
+
+#include <common.h>
+#include <linux/errno.h>
+#include <asm/io.h>
+#include <asm/arch/clock.h>
+#include <asm/arch/iomux.h>
+#include <asm/arch/imx-regs.h>
+
+#if	defined(CONFIG_MX23)
+#define	DRIVE_OFFSET	0x200
+#define	PULL_OFFSET	0x400
+#elif	defined(CONFIG_MX28)
+#define	DRIVE_OFFSET	0x300
+#define	PULL_OFFSET	0x600
+#else
+#error "Please select CONFIG_MX23 or CONFIG_MX28"
+#endif
+
+/*
+ * configures a single pad in the iomuxer
+ */
+int mxs_iomux_setup_pad(iomux_cfg_t pad)
+{
+	u32 reg, ofs, bp, bm;
+	void *iomux_base = (void *)MXS_PINCTRL_BASE;
+	struct mxs_register_32 *mxs_reg;
+
+	/* muxsel */
+	ofs = 0x100;
+	ofs += PAD_BANK(pad) * 0x20 + PAD_PIN(pad) / 16 * 0x10;
+	bp = PAD_PIN(pad) % 16 * 2;
+	bm = 0x3 << bp;
+	reg = readl(iomux_base + ofs);
+	reg &= ~bm;
+	reg |= PAD_MUXSEL(pad) << bp;
+	writel(reg, iomux_base + ofs);
+
+	/* drive */
+	ofs = DRIVE_OFFSET;
+	ofs += PAD_BANK(pad) * 0x40 + PAD_PIN(pad) / 8 * 0x10;
+	/* mA */
+	if (PAD_MA_VALID(pad)) {
+		bp = PAD_PIN(pad) % 8 * 4;
+		bm = 0x3 << bp;
+		reg = readl(iomux_base + ofs);
+		reg &= ~bm;
+		reg |= PAD_MA(pad) << bp;
+		writel(reg, iomux_base + ofs);
+	}
+	/* vol */
+	if (PAD_VOL_VALID(pad)) {
+		bp = PAD_PIN(pad) % 8 * 4 + 2;
+		mxs_reg = (struct mxs_register_32 *)(iomux_base + ofs);
+		if (PAD_VOL(pad))
+			writel(1 << bp, &mxs_reg->reg_set);
+		else
+			writel(1 << bp, &mxs_reg->reg_clr);
+	}
+
+	/* pull */
+	if (PAD_PULL_VALID(pad)) {
+		ofs = PULL_OFFSET;
+		ofs += PAD_BANK(pad) * 0x10;
+		bp = PAD_PIN(pad);
+		mxs_reg = (struct mxs_register_32 *)(iomux_base + ofs);
+		if (PAD_PULL(pad))
+			writel(1 << bp, &mxs_reg->reg_set);
+		else
+			writel(1 << bp, &mxs_reg->reg_clr);
+	}
+
+	return 0;
+}
+
+int mxs_iomux_setup_multiple_pads(const iomux_cfg_t *pad_list, unsigned count)
+{
+	const iomux_cfg_t *p = pad_list;
+	int i;
+	int ret;
+
+	for (i = 0; i < count; i++) {
+		ret = mxs_iomux_setup_pad(*p);
+		if (ret)
+			return ret;
+		p++;
+	}
+
+	return 0;
+}

source/bootloader/u-boot-2020.01/arch/arm/cpu/arm926ejs/mxs/mxs.c

@@ -0,0 +1,284 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Freescale i.MX23/i.MX28 common code
+ *
+ * Copyright (C) 2011 Marek Vasut <marek.vasut@gmail.com>
+ * on behalf of DENX Software Engineering GmbH
+ *
+ * Based on code from LTIB:
+ * Copyright (C) 2010 Freescale Semiconductor, Inc.
+ */
+
+#include <common.h>
+#include <linux/errno.h>
+#include <asm/io.h>
+#include <asm/arch/clock.h>
+#include <asm/mach-imx/dma.h>
+#include <asm/arch/gpio.h>
+#include <asm/arch/iomux.h>
+#include <asm/arch/imx-regs.h>
+#include <asm/arch/sys_proto.h>
+#include <linux/compiler.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/* Lowlevel init isn't used on i.MX28, so just have a dummy here */
+__weak void lowlevel_init(void) {}
+
+void reset_cpu(ulong ignored) __attribute__((noreturn));
+
+void reset_cpu(ulong ignored)
+{
+	struct mxs_rtc_regs *rtc_regs =
+		(struct mxs_rtc_regs *)MXS_RTC_BASE;
+	struct mxs_lcdif_regs *lcdif_regs =
+		(struct mxs_lcdif_regs *)MXS_LCDIF_BASE;
+
+	/*
+	 * Shut down the LCD controller as it interferes with BootROM boot mode
+	 * pads sampling.
+	 */
+	writel(LCDIF_CTRL_RUN, &lcdif_regs->hw_lcdif_ctrl_clr);
+
+	/* Wait 1 uS before doing the actual watchdog reset */
+	writel(1, &rtc_regs->hw_rtc_watchdog);
+	writel(RTC_CTRL_WATCHDOGEN, &rtc_regs->hw_rtc_ctrl_set);
+
+	/* Endless loop, reset will exit from here */
+	for (;;)
+		;
+}
+
+/*
+ * This function will craft a jumptable at 0x0 which will redirect interrupt
+ * vectoring to proper location of U-Boot in RAM.
+ *
+ * The structure of the jumptable will be as follows:
+ *  ldr pc, [pc, #0x18] ..... for each vector, thus repeated 8 times
+ *  <destination address> ... for each previous ldr, thus also repeated 8 times
+ *
+ * The "ldr pc, [pc, #0x18]" instruction above loads address from memory at
+ * offset 0x18 from current value of PC register. Note that PC is already
+ * incremented by 4 when computing the offset, so the effective offset is
+ * actually 0x20, this the associated <destination address>. Loading the PC
+ * register with an address performs a jump to that address.
+ */
+void mx28_fixup_vt(uint32_t start_addr)
+{
+	/* ldr pc, [pc, #0x18] */
+	const uint32_t ldr_pc = 0xe59ff018;
+	/* Jumptable location is 0x0 */
+	uint32_t *vt = (uint32_t *)0x0;
+	int i;
+
+	for (i = 0; i < 8; i++) {
+		/* cppcheck-suppress nullPointer */
+		vt[i] = ldr_pc;
+		/* cppcheck-suppress nullPointer */
+		vt[i + 8] = start_addr + (4 * i);
+	}
+}
+
+#ifdef	CONFIG_ARCH_MISC_INIT
+int arch_misc_init(void)
+{
+	mx28_fixup_vt(gd->relocaddr);
+	return 0;
+}
+#endif
+
+int arch_cpu_init(void)
+{
+	struct mxs_clkctrl_regs *clkctrl_regs =
+		(struct mxs_clkctrl_regs *)MXS_CLKCTRL_BASE;
+	extern uint32_t _start;
+
+	mx28_fixup_vt((uint32_t)&_start);
+
+	/*
+	 * Enable NAND clock
+	 */
+	/* Clear bypass bit */
+	writel(CLKCTRL_CLKSEQ_BYPASS_GPMI,
+		&clkctrl_regs->hw_clkctrl_clkseq_set);
+
+	/* Set GPMI clock to ref_gpmi / 12 */
+	clrsetbits_le32(&clkctrl_regs->hw_clkctrl_gpmi,
+		CLKCTRL_GPMI_CLKGATE | CLKCTRL_GPMI_DIV_MASK, 1);
+
+	udelay(1000);
+
+	/*
+	 * Configure GPIO unit
+	 */
+	mxs_gpio_init();
+
+#ifdef	CONFIG_APBH_DMA
+	/* Start APBH DMA */
+	mxs_dma_init();
+#endif
+
+	return 0;
+}
+
+u32 get_cpu_rev(void)
+{
+	struct mxs_digctl_regs *digctl_regs =
+		(struct mxs_digctl_regs *)MXS_DIGCTL_BASE;
+	uint8_t rev = readl(&digctl_regs->hw_digctl_chipid) & 0x000000FF;
+
+	switch (readl(&digctl_regs->hw_digctl_chipid) & HW_DIGCTL_CHIPID_MASK) {
+	case HW_DIGCTL_CHIPID_MX23:
+		switch (rev) {
+		case 0x0:
+		case 0x1:
+		case 0x2:
+		case 0x3:
+		case 0x4:
+			return (MXC_CPU_MX23 << 12) | (rev + 0x10);
+		default:
+			return 0;
+		}
+	case HW_DIGCTL_CHIPID_MX28:
+		switch (rev) {
+		case 0x1:
+			return (MXC_CPU_MX28 << 12) | 0x12;
+		default:
+			return 0;
+		}
+	default:
+		return 0;
+	}
+}
+
+#if defined(CONFIG_DISPLAY_CPUINFO)
+const char *get_imx_type(u32 imxtype)
+{
+	switch (imxtype) {
+	case MXC_CPU_MX23:
+		return "23";
+	case MXC_CPU_MX28:
+		return "28";
+	default:
+		return "??";
+	}
+}
+
+int print_cpuinfo(void)
+{
+	u32 cpurev;
+	struct mxs_spl_data *data = MXS_SPL_DATA;
+
+	cpurev = get_cpu_rev();
+	printf("CPU:   Freescale i.MX%s rev%d.%d at %d MHz\n",
+		get_imx_type((cpurev & 0xFF000) >> 12),
+		(cpurev & 0x000F0) >> 4,
+		(cpurev & 0x0000F) >> 0,
+		mxc_get_clock(MXC_ARM_CLK) / 1000000);
+	printf("BOOT:  %s\n", mxs_boot_modes[data->boot_mode_idx].mode);
+	return 0;
+}
+#endif
+
+int do_mx28_showclocks(cmd_tbl_t *cmdtp, int flag, int argc, char *const argv[])
+{
+	printf("CPU:   %3d MHz\n", mxc_get_clock(MXC_ARM_CLK) / 1000000);
+	printf("BUS:   %3d MHz\n", mxc_get_clock(MXC_AHB_CLK) / 1000000);
+	printf("EMI:   %3d MHz\n", mxc_get_clock(MXC_EMI_CLK));
+	printf("GPMI:  %3d MHz\n", mxc_get_clock(MXC_GPMI_CLK) / 1000000);
+	return 0;
+}
+
+/*
+ * Initializes on-chip ethernet controllers.
+ */
+#if defined(CONFIG_MX28) && defined(CONFIG_CMD_NET)
+int cpu_eth_init(bd_t *bis)
+{
+	struct mxs_clkctrl_regs *clkctrl_regs =
+		(struct mxs_clkctrl_regs *)MXS_CLKCTRL_BASE;
+
+	/* Turn on ENET clocks */
+	clrbits_le32(&clkctrl_regs->hw_clkctrl_enet,
+		CLKCTRL_ENET_SLEEP | CLKCTRL_ENET_DISABLE);
+
+	/* Set up ENET PLL for 50 MHz */
+	/* Power on ENET PLL */
+	writel(CLKCTRL_PLL2CTRL0_POWER,
+		&clkctrl_regs->hw_clkctrl_pll2ctrl0_set);
+
+	udelay(10);
+
+	/* Gate on ENET PLL */
+	writel(CLKCTRL_PLL2CTRL0_CLKGATE,
+		&clkctrl_regs->hw_clkctrl_pll2ctrl0_clr);
+
+	/* Enable pad output */
+	setbits_le32(&clkctrl_regs->hw_clkctrl_enet, CLKCTRL_ENET_CLK_OUT_EN);
+
+	return 0;
+}
+#endif
+
+__weak void mx28_adjust_mac(int dev_id, unsigned char *mac)
+{
+	mac[0] = 0x00;
+	mac[1] = 0x04; /* Use FSL vendor MAC address by default */
+
+	if (dev_id == 1) /* Let MAC1 be MAC0 + 1 by default */
+		mac[5] += 1;
+}
+
+#ifdef	CONFIG_MX28_FEC_MAC_IN_OCOTP
+
+#define	MXS_OCOTP_MAX_TIMEOUT	1000000
+void imx_get_mac_from_fuse(int dev_id, unsigned char *mac)
+{
+	struct mxs_ocotp_regs *ocotp_regs =
+		(struct mxs_ocotp_regs *)MXS_OCOTP_BASE;
+	uint32_t data;
+
+	memset(mac, 0, 6);
+
+	writel(OCOTP_CTRL_RD_BANK_OPEN, &ocotp_regs->hw_ocotp_ctrl_set);
+
+	if (mxs_wait_mask_clr(&ocotp_regs->hw_ocotp_ctrl_reg, OCOTP_CTRL_BUSY,
+				MXS_OCOTP_MAX_TIMEOUT)) {
+		printf("MXS FEC: Can't get MAC from OCOTP\n");
+		return;
+	}
+
+	data = readl(&ocotp_regs->hw_ocotp_cust0);
+
+	mac[2] = (data >> 24) & 0xff;
+	mac[3] = (data >> 16) & 0xff;
+	mac[4] = (data >> 8) & 0xff;
+	mac[5] = data & 0xff;
+	mx28_adjust_mac(dev_id, mac);
+}
+#else
+void imx_get_mac_from_fuse(int dev_id, unsigned char *mac)
+{
+	memset(mac, 0, 6);
+}
+#endif
+
+int mxs_dram_init(void)
+{
+	struct mxs_spl_data *data = MXS_SPL_DATA;
+
+	if (data->mem_dram_size == 0) {
+		printf("MXS:\n"
+			"Error, the RAM size passed up from SPL is 0!\n");
+		hang();
+	}
+
+	gd->ram_size = data->mem_dram_size;
+	return 0;
+}
+
+U_BOOT_CMD(
+	clocks,	CONFIG_SYS_MAXARGS, 1, do_mx28_showclocks,
+	"display clocks",
+	""
+);

source/bootloader/u-boot-2020.01/arch/arm/cpu/arm926ejs/mxs/mxs_init.h

@@ -0,0 +1,28 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Freescale i.MX28 SPL functions
+ *
+ * Copyright (C) 2011 Marek Vasut <marek.vasut@gmail.com>
+ * on behalf of DENX Software Engineering GmbH
+ */
+
+#ifndef	__M28_INIT_H__
+#define	__M28_INIT_H__
+
+void early_delay(int delay);
+
+void mxs_power_init(void);
+
+#ifdef	CONFIG_SPL_MXS_PSWITCH_WAIT
+void mxs_power_wait_pswitch(void);
+#else
+static inline void mxs_power_wait_pswitch(void) { }
+#endif
+
+void mxs_mem_init(void);
+uint32_t mxs_mem_get_size(void);
+
+void mxs_lradc_init(void);
+void mxs_lradc_enable_batt_measurement(void);
+
+#endif	/* __M28_INIT_H__ */

source/bootloader/u-boot-2020.01/arch/arm/cpu/arm926ejs/mxs/mxsimage-signed.cfg

@@ -0,0 +1,11 @@
+DISPLAYPROGRESS
+SECTION 0x0 BOOTABLE
+ TAG LAST
+ LOAD     0x1000     spl/u-boot-spl.bin
+ LOAD     0x8000     spl/u-boot-spl.ivt
+ LOAD     0x8040     spl/u-boot-spl.sig
+ CALL HAB 0x8000     0x0
+ LOAD     0x40002000 u-boot.bin
+ LOAD     0x40001000 u-boot.ivt
+ LOAD     0x40001040 u-boot.sig
+ CALL HAB 0x40001000 0x0

source/bootloader/u-boot-2020.01/arch/arm/cpu/arm926ejs/mxs/mxsimage-spl.mx23.cfg

@@ -0,0 +1,5 @@
+DISPLAYPROGRESS
+SECTION 0x0 BOOTABLE
+ TAG LAST
+ LOAD     0x1000     spl/u-boot-spl.bin
+ CALL     0x1000     0x0

source/bootloader/u-boot-2020.01/arch/arm/cpu/arm926ejs/mxs/mxsimage-spl.mx28.cfg

@@ -0,0 +1,6 @@
+DISPLAYPROGRESS
+SECTION 0x0 BOOTABLE
+ TAG LAST
+ LOAD     0x1000     spl/u-boot-spl.bin
+ LOAD IVT 0x8000     0x1000
+ CALL HAB 0x8000     0x0

source/bootloader/u-boot-2020.01/arch/arm/cpu/arm926ejs/mxs/mxsimage.mx23.cfg

@@ -0,0 +1,7 @@
+DISPLAYPROGRESS
+SECTION 0x0 BOOTABLE
+ TAG LAST
+ LOAD     0x1000     spl/u-boot-spl.bin
+ CALL     0x1000     0x0
+ LOAD     0x40002000 u-boot.bin
+ CALL     0x40002000 0x0

source/bootloader/u-boot-2020.01/arch/arm/cpu/arm926ejs/mxs/mxsimage.mx28.cfg

@@ -0,0 +1,9 @@
+DISPLAYPROGRESS
+SECTION 0x0 BOOTABLE
+ TAG LAST
+ LOAD     0x1000     spl/u-boot-spl.bin
+ LOAD IVT 0x8000     0x1000
+ CALL HAB 0x8000     0x0
+ LOAD     0x40002000 u-boot.bin
+ LOAD IVT 0x8000     0x40002000
+ CALL HAB 0x8000     0x0

source/bootloader/u-boot-2020.01/arch/arm/cpu/arm926ejs/mxs/spl_boot.c

@@ -0,0 +1,162 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Freescale i.MX28 Boot setup
+ *
+ * Copyright (C) 2011 Marek Vasut <marek.vasut@gmail.com>
+ * on behalf of DENX Software Engineering GmbH
+ */
+
+#include <common.h>
+#include <config.h>
+#include <serial.h>
+#include <asm/io.h>
+#include <asm/arch/imx-regs.h>
+#include <asm/arch/sys_proto.h>
+#include <asm/gpio.h>
+#include <linux/compiler.h>
+
+#include "mxs_init.h"
+
+DECLARE_GLOBAL_DATA_PTR;
+static gd_t gdata __section(".data");
+#ifdef CONFIG_SPL_SERIAL_SUPPORT
+static bd_t bdata __section(".data");
+#endif
+
+/*
+ * This delay function is intended to be used only in early stage of boot, where
+ * clock are not set up yet. The timer used here is reset on every boot and
+ * takes a few seconds to roll. The boot doesn't take that long, so to keep the
+ * code simple, it doesn't take rolling into consideration.
+ */
+void early_delay(int delay)
+{
+	struct mxs_digctl_regs *digctl_regs =
+		(struct mxs_digctl_regs *)MXS_DIGCTL_BASE;
+
+	uint32_t st = readl(&digctl_regs->hw_digctl_microseconds);
+	st += delay;
+	while (st > readl(&digctl_regs->hw_digctl_microseconds))
+		;
+}
+
+#if defined(CONFIG_MX23)
+#define	MUX_CONFIG_BOOTMODE_PAD	(MXS_PAD_3V3 | MXS_PAD_4MA | MXS_PAD_NOPULL)
+static const iomux_cfg_t iomux_boot[] = {
+	MX23_PAD_LCD_D00__GPIO_1_0 | MUX_CONFIG_BOOTMODE_PAD,
+	MX23_PAD_LCD_D01__GPIO_1_1 | MUX_CONFIG_BOOTMODE_PAD,
+	MX23_PAD_LCD_D02__GPIO_1_2 | MUX_CONFIG_BOOTMODE_PAD,
+	MX23_PAD_LCD_D03__GPIO_1_3 | MUX_CONFIG_BOOTMODE_PAD,
+	MX23_PAD_LCD_D04__GPIO_1_4 | MUX_CONFIG_BOOTMODE_PAD,
+	MX23_PAD_LCD_D05__GPIO_1_5 | MUX_CONFIG_BOOTMODE_PAD,
+};
+#endif
+
+static uint8_t mxs_get_bootmode_index(void)
+{
+	uint8_t bootmode = 0;
+	int i;
+	uint8_t masked;
+
+#if defined(CONFIG_MX23)
+	/* Setup IOMUX of bootmode pads to GPIO */
+	mxs_iomux_setup_multiple_pads(iomux_boot, ARRAY_SIZE(iomux_boot));
+
+	/* Setup bootmode pins as GPIO input */
+	gpio_direction_input(MX23_PAD_LCD_D00__GPIO_1_0);
+	gpio_direction_input(MX23_PAD_LCD_D01__GPIO_1_1);
+	gpio_direction_input(MX23_PAD_LCD_D02__GPIO_1_2);
+	gpio_direction_input(MX23_PAD_LCD_D03__GPIO_1_3);
+	gpio_direction_input(MX23_PAD_LCD_D05__GPIO_1_5);
+
+	/* Read bootmode pads */
+	bootmode |= (gpio_get_value(MX23_PAD_LCD_D00__GPIO_1_0) ? 1 : 0) << 0;
+	bootmode |= (gpio_get_value(MX23_PAD_LCD_D01__GPIO_1_1) ? 1 : 0) << 1;
+	bootmode |= (gpio_get_value(MX23_PAD_LCD_D02__GPIO_1_2) ? 1 : 0) << 2;
+	bootmode |= (gpio_get_value(MX23_PAD_LCD_D03__GPIO_1_3) ? 1 : 0) << 3;
+	bootmode |= (gpio_get_value(MX23_PAD_LCD_D05__GPIO_1_5) ? 1 : 0) << 5;
+#elif defined(CONFIG_MX28)
+	/* The global boot mode will be detected by ROM code and its value
+	 * is stored at the fixed address 0x00019BF0 in OCRAM.
+	 */
+#define GLOBAL_BOOT_MODE_ADDR 0x00019BF0
+	bootmode = __raw_readl(GLOBAL_BOOT_MODE_ADDR);
+#endif
+
+	for (i = 0; i < ARRAY_SIZE(mxs_boot_modes); i++) {
+		masked = bootmode & mxs_boot_modes[i].boot_mask;
+		if (masked == mxs_boot_modes[i].boot_pads)
+			break;
+	}
+
+	return i;
+}
+
+static void mxs_spl_fixup_vectors(void)
+{
+	/*
+	 * Copy our vector table to 0x0, since due to HAB, we cannot
+	 * be loaded to 0x0. We want to have working vectoring though,
+	 * thus this fixup. Our vectoring table is PIC, so copying is
+	 * fine.
+	 */
+	extern uint32_t _start;
+
+	/* cppcheck-suppress nullPointer */
+	memcpy(0x0, &_start, 0x60);
+}
+
+static void mxs_spl_console_init(void)
+{
+#ifdef CONFIG_SPL_SERIAL_SUPPORT
+	gd->bd = &bdata;
+	gd->baudrate = CONFIG_BAUDRATE;
+	serial_init();
+	gd->have_console = 1;
+#endif
+}
+
+void mxs_common_spl_init(const uint32_t arg, const uint32_t *resptr,
+			 const iomux_cfg_t *iomux_setup,
+			 const unsigned int iomux_size)
+{
+	struct mxs_spl_data *data = MXS_SPL_DATA;
+	uint8_t bootmode = mxs_get_bootmode_index();
+	gd = &gdata;
+
+	mxs_spl_fixup_vectors();
+
+	mxs_iomux_setup_multiple_pads(iomux_setup, iomux_size);
+
+	mxs_spl_console_init();
+	debug("SPL: Serial Console Initialised\n");
+
+	mxs_power_init();
+
+	mxs_mem_init();
+	data->mem_dram_size = mxs_mem_get_size();
+
+	data->boot_mode_idx = bootmode;
+
+	mxs_power_wait_pswitch();
+
+	if (mxs_boot_modes[data->boot_mode_idx].boot_pads == MXS_BM_JTAG) {
+		debug("SPL: Waiting for JTAG user\n");
+		asm volatile ("x: b x");
+	}
+}
+
+#ifndef CONFIG_SPL_FRAMEWORK
+/* Support aparatus */
+inline void board_init_f(unsigned long bootflag)
+{
+	for (;;)
+		;
+}
+
+inline void board_init_r(gd_t *id, ulong dest_addr)
+{
+	for (;;)
+		;
+}
+#endif

source/bootloader/u-boot-2020.01/arch/arm/cpu/arm926ejs/mxs/spl_lradc_init.c

@@ -0,0 +1,78 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Freescale i.MX28 Battery measurement init
+ *
+ * Copyright (C) 2011 Marek Vasut <marek.vasut@gmail.com>
+ * on behalf of DENX Software Engineering GmbH
+ */
+
+#include <common.h>
+#include <config.h>
+#include <asm/io.h>
+#include <asm/arch/imx-regs.h>
+
+#include "mxs_init.h"
+
+void mxs_lradc_init(void)
+{
+	struct mxs_lradc_regs *regs = (struct mxs_lradc_regs *)MXS_LRADC_BASE;
+
+	debug("SPL: Initialisating LRADC\n");
+
+	writel(LRADC_CTRL0_SFTRST, &regs->hw_lradc_ctrl0_clr);
+	writel(LRADC_CTRL0_CLKGATE, &regs->hw_lradc_ctrl0_clr);
+	writel(LRADC_CTRL0_ONCHIP_GROUNDREF, &regs->hw_lradc_ctrl0_clr);
+
+	clrsetbits_le32(&regs->hw_lradc_ctrl3,
+			LRADC_CTRL3_CYCLE_TIME_MASK,
+			LRADC_CTRL3_CYCLE_TIME_6MHZ);
+
+	clrsetbits_le32(&regs->hw_lradc_ctrl4,
+			LRADC_CTRL4_LRADC7SELECT_MASK |
+			LRADC_CTRL4_LRADC6SELECT_MASK,
+			LRADC_CTRL4_LRADC7SELECT_CHANNEL7 |
+			LRADC_CTRL4_LRADC6SELECT_CHANNEL10);
+}
+
+void mxs_lradc_enable_batt_measurement(void)
+{
+	struct mxs_lradc_regs *regs = (struct mxs_lradc_regs *)MXS_LRADC_BASE;
+
+	debug("SPL: Enabling LRADC battery measurement\n");
+
+	/* Check if the channel is present at all. */
+	if (!(readl(&regs->hw_lradc_status) & LRADC_STATUS_CHANNEL7_PRESENT)) {
+		debug("SPL: LRADC channel 7 is not present - aborting\n");
+		return;
+	}
+
+	debug("SPL: LRADC channel 7 is present - configuring\n");
+
+	writel(LRADC_CTRL1_LRADC7_IRQ_EN, &regs->hw_lradc_ctrl1_clr);
+	writel(LRADC_CTRL1_LRADC7_IRQ, &regs->hw_lradc_ctrl1_clr);
+
+	clrsetbits_le32(&regs->hw_lradc_conversion,
+			LRADC_CONVERSION_SCALE_FACTOR_MASK,
+			LRADC_CONVERSION_SCALE_FACTOR_LI_ION);
+	writel(LRADC_CONVERSION_AUTOMATIC, &regs->hw_lradc_conversion_set);
+
+	/* Configure the channel. */
+	writel((1 << 7) << LRADC_CTRL2_DIVIDE_BY_TWO_OFFSET,
+		&regs->hw_lradc_ctrl2_clr);
+	writel(0xffffffff, &regs->hw_lradc_ch7_clr);
+	clrbits_le32(&regs->hw_lradc_ch7, LRADC_CH_NUM_SAMPLES_MASK);
+	writel(LRADC_CH_ACCUMULATE, &regs->hw_lradc_ch7_clr);
+
+	/* Schedule the channel. */
+	writel(1 << 7, &regs->hw_lradc_ctrl0_set);
+
+	/* Start the channel sampling. */
+	writel(((1 << 7) << LRADC_DELAY_TRIGGER_LRADCS_OFFSET) |
+		((1 << 3) << LRADC_DELAY_TRIGGER_DELAYS_OFFSET) |
+		100, &regs->hw_lradc_delay3);
+
+	writel(0xffffffff, &regs->hw_lradc_ch7_clr);
+	writel(LRADC_DELAY_KICK, &regs->hw_lradc_delay3_set);
+
+	debug("SPL: LRADC channel 7 configuration complete\n");
+}

source/bootloader/u-boot-2020.01/arch/arm/cpu/arm926ejs/mxs/spl_mem_init.c

@@ -0,0 +1,359 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Freescale i.MX28 RAM init
+ *
+ * Copyright (C) 2011 Marek Vasut <marek.vasut@gmail.com>
+ * on behalf of DENX Software Engineering GmbH
+ */
+
+#include <common.h>
+#include <config.h>
+#include <asm/io.h>
+#include <asm/arch/imx-regs.h>
+#include <asm/arch/sys_proto.h>
+#include <linux/compiler.h>
+
+#include "mxs_init.h"
+
+__weak uint32_t mxs_dram_vals[] = {
+/*
+ * i.MX28 DDR2 at 200MHz
+ */
+#if defined(CONFIG_MX28)
+	0x00000000, 0x00000000, 0x00000000, 0x00000000,
+	0x00000000, 0x00000000, 0x00000000, 0x00000000,
+	0x00000000, 0x00000000, 0x00000000, 0x00000000,
+	0x00000000, 0x00000000, 0x00000000, 0x00000000,
+	0x00000000, 0x00000100, 0x00000000, 0x00000000,
+	0x00000000, 0x00000000, 0x00000000, 0x00000000,
+	0x00000000, 0x00000000, 0x00010101, 0x01010101,
+	0x000f0f01, 0x0f02020a, 0x00000000, 0x00010101,
+	0x00000100, 0x00000100, 0x00000000, 0x00000002,
+	0x01010000, 0x07080403, 0x06005003, 0x0a0000c8,
+	0x02009c40, 0x0002030c, 0x0036a609, 0x031a0612,
+	0x02030202, 0x00c8001c, 0x00000000, 0x00000000,
+	0x00012100, 0xffff0303, 0x00012100, 0xffff0303,
+	0x00012100, 0xffff0303, 0x00012100, 0xffff0303,
+	0x00000003, 0x00000000, 0x00000000, 0x00000000,
+	0x00000000, 0x00000000, 0x00000000, 0x00000000,
+	0x00000000, 0x00000000, 0x00000612, 0x01000F02,
+	0x06120612, 0x00000200, 0x00020007, 0xf4004a27,
+	0xf4004a27, 0xf4004a27, 0xf4004a27, 0x07000300,
+	0x07000300, 0x07400300, 0x07400300, 0x00000005,
+	0x00000000, 0x00000000, 0x01000000, 0x01020408,
+	0x08040201, 0x000f1133, 0x00000000, 0x00001f04,
+	0x00001f04, 0x00001f04, 0x00001f04, 0x00001f04,
+	0x00001f04, 0x00001f04, 0x00001f04, 0x00000000,
+	0x00000000, 0x00000000, 0x00000000, 0x00000000,
+	0x00000000, 0x00000000, 0x00000000, 0x00000000,
+	0x00000000, 0x00000000, 0x00000000, 0x00000000,
+	0x00000000, 0x00000000, 0x00000000, 0x00000000,
+	0x00000000, 0x00000000, 0x00000000, 0x00000000,
+	0x00000000, 0x00000000, 0x00000000, 0x00000000,
+	0x00000000, 0x00000000, 0x00000000, 0x00000000,
+	0x00000000, 0x00000000, 0x00000000, 0x00000000,
+	0x00000000, 0x00000000, 0x00000000, 0x00000000,
+	0x00000000, 0x00000000, 0x00000000, 0x00000000,
+	0x00000000, 0x00000000, 0x00000000, 0x00000000,
+	0x00000000, 0x00000000, 0x00000000, 0x00000000,
+	0x00000000, 0x00000000, 0x00000000, 0x00000000,
+	0x00000000, 0x00000000, 0x00000000, 0x00000000,
+	0x00000000, 0x00000000, 0x00000000, 0x00000000,
+	0x00000000, 0x00000000, 0x00000000, 0x00000000,
+	0x00000000, 0x00000000, 0x00010000, 0x00030404,
+	0x00000003, 0x00000000, 0x00000000, 0x00000000,
+	0x00000000, 0x00000000, 0x00000000, 0x01010000,
+	0x01000000, 0x03030000, 0x00010303, 0x01020202,
+	0x00000000, 0x02040303, 0x21002103, 0x00061200,
+	0x06120612, 0x04420442, 0x04420442, 0x00040004,
+	0x00040004, 0x00000000, 0x00000000, 0x00000000,
+	0x00000000, 0xffffffff
+
+/*
+ * i.MX23 DDR at 133MHz
+ */
+#elif defined(CONFIG_MX23)
+	0x01010001, 0x00010100, 0x01000101, 0x00000001,
+	0x00000101, 0x00000000, 0x00010000, 0x01000001,
+	0x00000000, 0x00000001, 0x07000200, 0x00070202,
+	0x02020000, 0x04040a01, 0x00000201, 0x02040000,
+	0x02000000, 0x19000f08, 0x0d0d0000, 0x02021313,
+	0x02061521, 0x0000000a, 0x00080008, 0x00200020,
+	0x00200020, 0x00200020, 0x000003f7, 0x00000000,
+	0x00000000, 0x00000020, 0x00000020, 0x00c80000,
+	0x000a23cd, 0x000000c8, 0x00006665, 0x00000000,
+	0x00000101, 0x00040001, 0x00000000, 0x00000000,
+	0x00010000
+#else
+#error Unsupported memory initialization
+#endif
+};
+
+__weak void mxs_adjust_memory_params(uint32_t *dram_vals)
+{
+	debug("SPL: Using default SDRAM parameters\n");
+}
+
+#ifdef CONFIG_MX28
+static void initialize_dram_values(void)
+{
+	int i;
+
+	debug("SPL: Setting mx28 board specific SDRAM parameters\n");
+	mxs_adjust_memory_params(mxs_dram_vals);
+
+	debug("SPL: Applying SDRAM parameters\n");
+	for (i = 0; i < ARRAY_SIZE(mxs_dram_vals); i++)
+		writel(mxs_dram_vals[i], MXS_DRAM_BASE + (4 * i));
+}
+#else
+static void initialize_dram_values(void)
+{
+	int i;
+
+	debug("SPL: Setting mx23 board specific SDRAM parameters\n");
+	mxs_adjust_memory_params(mxs_dram_vals);
+
+	/*
+	 * HW_DRAM_CTL27, HW_DRAM_CTL28 and HW_DRAM_CTL35 are not initialized as
+	 * per FSL bootlets code.
+	 *
+	 * mx23 Reference Manual marks HW_DRAM_CTL27 and HW_DRAM_CTL28 as
+	 * "reserved".
+	 * HW_DRAM_CTL8 is setup as the last element.
+	 * So skip the initialization of these HW_DRAM_CTL registers.
+	 */
+	debug("SPL: Applying SDRAM parameters\n");
+	for (i = 0; i < ARRAY_SIZE(mxs_dram_vals); i++) {
+		if (i == 8 || i == 27 || i == 28 || i == 35)
+			continue;
+		writel(mxs_dram_vals[i], MXS_DRAM_BASE + (4 * i));
+	}
+
+	/*
+	 * Enable tRAS lockout in HW_DRAM_CTL08 ; it must be the last
+	 * element to be set
+	 */
+	writel((1 << 24), MXS_DRAM_BASE + (4 * 8));
+}
+#endif
+
+static void mxs_mem_init_clock(void)
+{
+	struct mxs_clkctrl_regs *clkctrl_regs =
+		(struct mxs_clkctrl_regs *)MXS_CLKCTRL_BASE;
+#if defined(CONFIG_MX23)
+	/* Fractional divider for ref_emi is 33 ; 480 * 18 / 33 = 266MHz */
+	const unsigned char divider = 33;
+#elif defined(CONFIG_MX28)
+	/* Fractional divider for ref_emi is 21 ; 480 * 18 / 21 = 411MHz */
+	const unsigned char divider = 21;
+#endif
+
+	debug("SPL: Initialising FRAC0\n");
+
+	/* Gate EMI clock */
+	writeb(CLKCTRL_FRAC_CLKGATE,
+		&clkctrl_regs->hw_clkctrl_frac0_set[CLKCTRL_FRAC0_EMI]);
+
+	/* Set fractional divider for ref_emi */
+	writeb(CLKCTRL_FRAC_CLKGATE | (divider & CLKCTRL_FRAC_FRAC_MASK),
+		&clkctrl_regs->hw_clkctrl_frac0[CLKCTRL_FRAC0_EMI]);
+
+	/* Ungate EMI clock */
+	writeb(CLKCTRL_FRAC_CLKGATE,
+		&clkctrl_regs->hw_clkctrl_frac0_clr[CLKCTRL_FRAC0_EMI]);
+
+	early_delay(11000);
+
+	/* Set EMI clock divider for EMI clock to 411 / 2 = 205MHz */
+	writel((2 << CLKCTRL_EMI_DIV_EMI_OFFSET) |
+		(1 << CLKCTRL_EMI_DIV_XTAL_OFFSET),
+		&clkctrl_regs->hw_clkctrl_emi);
+
+	/* Unbypass EMI */
+	writel(CLKCTRL_CLKSEQ_BYPASS_EMI,
+		&clkctrl_regs->hw_clkctrl_clkseq_clr);
+
+	early_delay(10000);
+	debug("SPL: FRAC0 Initialised\n");
+}
+
+static void mxs_mem_setup_cpu_and_hbus(void)
+{
+	struct mxs_clkctrl_regs *clkctrl_regs =
+		(struct mxs_clkctrl_regs *)MXS_CLKCTRL_BASE;
+
+	debug("SPL: Setting CPU and HBUS clock frequencies\n");
+
+	/* Set fractional divider for ref_cpu to 480 * 18 / 19 = 454MHz
+	 * and ungate CPU clock */
+	writeb(19 & CLKCTRL_FRAC_FRAC_MASK,
+		(uint8_t *)&clkctrl_regs->hw_clkctrl_frac0[CLKCTRL_FRAC0_CPU]);
+
+	/* Set CPU bypass */
+	writel(CLKCTRL_CLKSEQ_BYPASS_CPU,
+		&clkctrl_regs->hw_clkctrl_clkseq_set);
+
+	/* HBUS = 151MHz */
+	writel(CLKCTRL_HBUS_DIV_MASK, &clkctrl_regs->hw_clkctrl_hbus_set);
+	writel(((~3) << CLKCTRL_HBUS_DIV_OFFSET) & CLKCTRL_HBUS_DIV_MASK,
+		&clkctrl_regs->hw_clkctrl_hbus_clr);
+
+	early_delay(10000);
+
+	/* CPU clock divider = 1 */
+	clrsetbits_le32(&clkctrl_regs->hw_clkctrl_cpu,
+			CLKCTRL_CPU_DIV_CPU_MASK, 1);
+
+	/* Disable CPU bypass */
+	writel(CLKCTRL_CLKSEQ_BYPASS_CPU,
+		&clkctrl_regs->hw_clkctrl_clkseq_clr);
+
+	early_delay(15000);
+}
+
+static void mxs_mem_setup_vdda(void)
+{
+	struct mxs_power_regs *power_regs =
+		(struct mxs_power_regs *)MXS_POWER_BASE;
+
+	debug("SPL: Configuring VDDA\n");
+
+	writel((0xc << POWER_VDDACTRL_TRG_OFFSET) |
+		(0x7 << POWER_VDDACTRL_BO_OFFSET_OFFSET) |
+		POWER_VDDACTRL_LINREG_OFFSET_1STEPS_BELOW,
+		&power_regs->hw_power_vddactrl);
+}
+
+uint32_t mxs_mem_get_size(void)
+{
+	uint32_t sz, da;
+	uint32_t *vt = (uint32_t *)0x20;
+	/* The following is "subs pc, r14, #4", used as return from DABT. */
+	const uint32_t data_abort_memdetect_handler = 0xe25ef004;
+
+	/* Replace the DABT handler. */
+	da = vt[4];
+	vt[4] = data_abort_memdetect_handler;
+
+	sz = get_ram_size((long *)PHYS_SDRAM_1, PHYS_SDRAM_1_SIZE);
+
+	/* Restore the old DABT handler. */
+	vt[4] = da;
+
+	return sz;
+}
+
+#ifdef CONFIG_MX23
+static void mx23_mem_setup_vddmem(void)
+{
+	struct mxs_power_regs *power_regs =
+		(struct mxs_power_regs *)MXS_POWER_BASE;
+
+	debug("SPL: Setting mx23 VDDMEM\n");
+
+	/* We must wait before and after disabling the current limiter! */
+	early_delay(10000);
+
+	clrbits_le32(&power_regs->hw_power_vddmemctrl,
+		POWER_VDDMEMCTRL_ENABLE_ILIMIT);
+
+	early_delay(10000);
+
+}
+
+static void mx23_mem_init(void)
+{
+	debug("SPL: Initialising mx23 SDRAM Controller\n");
+
+	/*
+	 * Reset/ungate the EMI block. This is essential, otherwise the system
+	 * suffers from memory instability. This thing is mx23 specific and is
+	 * no longer present on mx28.
+	 */
+	mxs_reset_block((struct mxs_register_32 *)MXS_EMI_BASE);
+
+	mx23_mem_setup_vddmem();
+
+	/*
+	 * Configure the DRAM registers
+	 */
+
+	/* Clear START and SREFRESH bit from DRAM_CTL8 */
+	clrbits_le32(MXS_DRAM_BASE + 0x20, (1 << 16) | (1 << 8));
+
+	initialize_dram_values();
+
+	/* Set START bit in DRAM_CTL8 */
+	setbits_le32(MXS_DRAM_BASE + 0x20, 1 << 16);
+
+	clrbits_le32(MXS_DRAM_BASE + 0x40, 1 << 17);
+
+	/* Wait for EMI_STAT bit DRAM_HALTED */
+	for (;;) {
+		if (!(readl(MXS_EMI_BASE + 0x10) & (1 << 1)))
+			break;
+		early_delay(1000);
+	}
+
+	/* Adjust EMI port priority. */
+	clrsetbits_le32(0x80020000, 0x1f << 16, 0x2);
+	early_delay(20000);
+
+	setbits_le32(MXS_DRAM_BASE + 0x40, 1 << 19);
+	setbits_le32(MXS_DRAM_BASE + 0x40, 1 << 11);
+}
+#endif
+
+#ifdef CONFIG_MX28
+static void mx28_mem_init(void)
+{
+	struct mxs_pinctrl_regs *pinctrl_regs =
+		(struct mxs_pinctrl_regs *)MXS_PINCTRL_BASE;
+
+	debug("SPL: Initialising mx28 SDRAM Controller\n");
+
+	/* Set DDR2 mode */
+	writel(PINCTRL_EMI_DS_CTRL_DDR_MODE_DDR2,
+		&pinctrl_regs->hw_pinctrl_emi_ds_ctrl_set);
+
+	/*
+	 * Configure the DRAM registers
+	 */
+
+	/* Clear START bit from DRAM_CTL16 */
+	clrbits_le32(MXS_DRAM_BASE + 0x40, 1);
+
+	initialize_dram_values();
+
+	/* Clear SREFRESH bit from DRAM_CTL17 */
+	clrbits_le32(MXS_DRAM_BASE + 0x44, 1);
+
+	/* Set START bit in DRAM_CTL16 */
+	setbits_le32(MXS_DRAM_BASE + 0x40, 1);
+
+	/* Wait for bit 20 (DRAM init complete) in DRAM_CTL58 */
+	while (!(readl(MXS_DRAM_BASE + 0xe8) & (1 << 20)))
+		;
+}
+#endif
+
+void mxs_mem_init(void)
+{
+	early_delay(11000);
+
+	mxs_mem_init_clock();
+
+	mxs_mem_setup_vdda();
+
+#if defined(CONFIG_MX23)
+	mx23_mem_init();
+#elif defined(CONFIG_MX28)
+	mx28_mem_init();
+#endif
+
+	early_delay(10000);
+
+	mxs_mem_setup_cpu_and_hbus();
+}

source/bootloader/u-boot-2020.01/arch/arm/cpu/arm926ejs/mxs/start.S

@@ -0,0 +1,95 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ *  armboot - Startup Code for ARM926EJS CPU-core
+ *
+ *  Copyright (c) 2003  Texas Instruments
+ *
+ *  ----- Adapted for OMAP1610 OMAP730 from ARM925t code ------
+ *
+ *  Copyright (c) 2001	Marius Groger <mag@sysgo.de>
+ *  Copyright (c) 2002	Alex Zupke <azu@sysgo.de>
+ *  Copyright (c) 2002	Gary Jennejohn <garyj@denx.de>
+ *  Copyright (c) 2003	Richard Woodruff <r-woodruff2@ti.com>
+ *  Copyright (c) 2003	Kshitij <kshitij@ti.com>
+ *  Copyright (c) 2010	Albert Aribaud <albert.u.boot@aribaud.net>
+ *
+ * Change to support call back into iMX28 bootrom
+ * Copyright (c) 2011 Marek Vasut <marek.vasut@gmail.com>
+ * on behalf of DENX Software Engineering GmbH
+ */
+
+#include <asm-offsets.h>
+#include <config.h>
+#include <common.h>
+
+/*
+ *************************************************************************
+ *
+ * Startup Code (reset vector)
+ *
+ * do important init only if we don't start from memory!
+ * setup Memory and board specific bits prior to relocation.
+ * relocate armboot to ram
+ * setup stack
+ *
+ *************************************************************************
+ */
+
+	.globl	reset
+reset:
+	/*
+	 * If the CPU is configured in "Wait JTAG connection mode", the stack
+	 * pointer is not configured and is zero. This will cause crash when
+	 * trying to push data onto stack right below here. Load the SP and make
+	 * it point to the end of OCRAM if the SP is zero.
+	 */
+	cmp	sp, #0x00000000
+	ldreq	sp, =CONFIG_SYS_INIT_SP_ADDR
+
+	/*
+	 * Store all registers on old stack pointer, this will allow us later to
+	 * return to the BootROM and let the BootROM load U-Boot into RAM.
+	 *
+	 * WARNING: Register r0 and r1 are used by the BootROM to pass data
+	 *          to the called code. Register r0 will contain arbitrary
+	 *          data that are set in the BootStream. In case this code
+	 *          was started with CALL instruction, register r1 will contain
+	 *          pointer to the return value this function can then set.
+	 *          The code below MUST NOT CHANGE register r0 and r1 !
+	 */
+	push	{r0-r12,r14}
+
+	/* Save control register c1 */
+	mrc	p15, 0, r2, c1, c0, 0
+	push	{r2}
+
+	/* Set the cpu to SVC32 mode and store old CPSR register content. */
+	mrs	r2, cpsr
+	push	{r2}
+	bic	r2, r2, #0x1f
+	orr	r2, r2, #0xd3
+	msr	cpsr, r2
+
+	bl	board_init_ll
+
+	/* Restore BootROM's CPU mode (especially FIQ). */
+	pop	{r2}
+	msr	cpsr,r2
+
+	/*
+	 * Restore c1 register. Especially set exception vector location
+	 * back to BootROM space which is required by bootrom for USB boot.
+	 */
+	pop	{r2}
+	mcr	p15, 0, r2, c1, c0, 0
+
+	pop	{r0-r12,r14}
+
+	/*
+	 * In case this code was started by the CALL instruction, the register
+	 * r0 is examined by the BootROM after this code returns. The value in
+	 * r0 must be set to 0 to indicate successful return.
+	 */
+	mov r0, #0
+
+	bx	lr

source/bootloader/u-boot-2020.01/arch/arm/cpu/arm926ejs/mxs/timer.c

@@ -0,0 +1,156 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Freescale i.MX28 timer driver
+ *
+ * Copyright (C) 2011 Marek Vasut <marek.vasut@gmail.com>
+ * on behalf of DENX Software Engineering GmbH
+ *
+ * Based on code from LTIB:
+ * (C) Copyright 2009-2010 Freescale Semiconductor, Inc.
+ */
+
+#include <common.h>
+#include <time.h>
+#include <asm/io.h>
+#include <asm/arch/imx-regs.h>
+#include <asm/arch/sys_proto.h>
+
+/* Maximum fixed count */
+#if defined(CONFIG_MX23)
+#define TIMER_LOAD_VAL 0xffff
+#elif defined(CONFIG_MX28)
+#define TIMER_LOAD_VAL 0xffffffff
+#endif
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#define timestamp (gd->arch.tbl)
+#define lastdec (gd->arch.lastinc)
+
+/*
+ * This driver uses 1kHz clock source.
+ */
+#define	MXS_INCREMENTER_HZ		1000
+
+static inline unsigned long tick_to_time(unsigned long tick)
+{
+	return tick / (MXS_INCREMENTER_HZ / CONFIG_SYS_HZ);
+}
+
+static inline unsigned long time_to_tick(unsigned long time)
+{
+	return time * (MXS_INCREMENTER_HZ / CONFIG_SYS_HZ);
+}
+
+/* Calculate how many ticks happen in "us" microseconds */
+static inline unsigned long us_to_tick(unsigned long us)
+{
+	return (us * MXS_INCREMENTER_HZ) / 1000000;
+}
+
+int timer_init(void)
+{
+	struct mxs_timrot_regs *timrot_regs =
+		(struct mxs_timrot_regs *)MXS_TIMROT_BASE;
+
+	/* Reset Timers and Rotary Encoder module */
+	mxs_reset_block(&timrot_regs->hw_timrot_rotctrl_reg);
+
+	/* Set fixed_count to 0 */
+#if defined(CONFIG_MX23)
+	writel(0, &timrot_regs->hw_timrot_timcount0);
+#elif defined(CONFIG_MX28)
+	writel(0, &timrot_regs->hw_timrot_fixed_count0);
+#endif
+
+	/* Set UPDATE bit and 1Khz frequency */
+	writel(TIMROT_TIMCTRLn_UPDATE | TIMROT_TIMCTRLn_RELOAD |
+		TIMROT_TIMCTRLn_SELECT_1KHZ_XTAL,
+		&timrot_regs->hw_timrot_timctrl0);
+
+	/* Set fixed_count to maximal value */
+#if defined(CONFIG_MX23)
+	writel(TIMER_LOAD_VAL - 1, &timrot_regs->hw_timrot_timcount0);
+#elif defined(CONFIG_MX28)
+	writel(TIMER_LOAD_VAL, &timrot_regs->hw_timrot_fixed_count0);
+#endif
+
+	return 0;
+}
+
+unsigned long long get_ticks(void)
+{
+	struct mxs_timrot_regs *timrot_regs =
+		(struct mxs_timrot_regs *)MXS_TIMROT_BASE;
+	uint32_t now;
+
+	/* Current tick value */
+#if defined(CONFIG_MX23)
+	/* Upper bits are the valid ones. */
+	now = readl(&timrot_regs->hw_timrot_timcount0) >>
+		TIMROT_RUNNING_COUNTn_RUNNING_COUNT_OFFSET;
+#elif defined(CONFIG_MX28)
+	now = readl(&timrot_regs->hw_timrot_running_count0);
+#else
+#error "Don't know how to read timrot_regs"
+#endif
+
+	if (lastdec >= now) {
+		/*
+		 * normal mode (non roll)
+		 * move stamp forward with absolut diff ticks
+		 */
+		timestamp += (lastdec - now);
+	} else {
+		/* we have rollover of decrementer */
+		timestamp += (TIMER_LOAD_VAL - now) + lastdec;
+
+	}
+	lastdec = now;
+
+	return timestamp;
+}
+
+ulong get_timer(ulong base)
+{
+	return tick_to_time(get_ticks()) - base;
+}
+
+/* We use the HW_DIGCTL_MICROSECONDS register for sub-millisecond timer. */
+#define	MXS_HW_DIGCTL_MICROSECONDS	0x8001c0c0
+
+void __udelay(unsigned long usec)
+{
+	uint32_t old, new, incr;
+	uint32_t counter = 0;
+
+	old = readl(MXS_HW_DIGCTL_MICROSECONDS);
+
+	while (counter < usec) {
+		new = readl(MXS_HW_DIGCTL_MICROSECONDS);
+
+		/* Check if the timer wrapped. */
+		if (new < old) {
+			incr = 0xffffffff - old;
+			incr += new;
+		} else {
+			incr = new - old;
+		}
+
+		/*
+		 * Check if we are close to the maximum time and the counter
+		 * would wrap if incremented. If that's the case, break out
+		 * from the loop as the requested delay time passed.
+		 */
+		if (counter + incr < counter)
+			break;
+
+		counter += incr;
+		old = new;
+	}
+}
+
+ulong get_tbclk(void)
+{
+	return MXS_INCREMENTER_HZ;
+}

source/bootloader/u-boot-2020.01/arch/arm/cpu/arm926ejs/mxs/u-boot-imx23.bd

@@ -0,0 +1,18 @@
+options {
+	driveTag = 0x00;
+	flags = 0x01;
+}
+
+sources {
+	u_boot_spl="spl/u-boot-spl.bin";
+	u_boot="u-boot.bin";
+}
+
+section (0) {
+	load u_boot_spl > 0x0000;
+	load ivt (entry = 0x0014) > 0x8000;
+	call 0x8000;
+
+	load u_boot > 0x40000100;
+	call 0x40000100;
+}

source/bootloader/u-boot-2020.01/arch/arm/cpu/arm926ejs/mxs/u-boot-imx28.bd

@@ -0,0 +1,14 @@
+sources {
+	u_boot_spl="spl/u-boot-spl.bin";
+	u_boot="u-boot.bin";
+}
+
+section (0) {
+	load u_boot_spl > 0x0000;
+	load ivt (entry = 0x0014) > 0x8000;
+	hab call 0x8000;
+
+	load u_boot > 0x40000100;
+	load ivt (entry = 0x40000100) > 0x8000;
+	hab call 0x8000;
+}

source/bootloader/u-boot-2020.01/arch/arm/cpu/arm926ejs/mxs/u-boot-spl.lds

@@ -0,0 +1,68 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright (C) 2011 Marek Vasut <marek.vasut@gmail.com>
+ * on behalf of DENX Software Engineering GmbH
+ *
+ * January 2004 - Changed to support H4 device
+ * Copyright (c) 2004-2008 Texas Instruments
+ *
+ * (C) Copyright 2002
+ * Gary Jennejohn, DENX Software Engineering, <garyj@denx.de>
+ */
+
+OUTPUT_FORMAT("elf32-littlearm", "elf32-littlearm", "elf32-littlearm")
+OUTPUT_ARCH(arm)
+ENTRY(_start)
+SECTIONS
+{
+	. = IMAGE_TEXT_BASE;
+
+	. = ALIGN(4);
+	.text	:
+	{
+		*(.vectors)
+		arch/arm/cpu/arm926ejs/mxs/start.o	(.text*)
+		*(.text*)
+	}
+
+	. = ALIGN(4);
+	.rodata : { *(SORT_BY_ALIGNMENT(SORT_BY_NAME(.rodata*))) }
+
+	. = ALIGN(4);
+	.data : {
+		*(.data*)
+	}
+
+	. = ALIGN(4);
+
+	.rel.dyn : {
+		__rel_dyn_start = .;
+		*(.rel*)
+		__rel_dyn_end = .;
+	}
+
+	.bss : {
+		. = ALIGN(4);
+		__bss_start = .;
+		*(.bss*)
+		. = ALIGN(4);
+		__bss_end = .;
+	}
+
+	.end :
+	{
+		*(.__end)
+	}
+
+	_image_binary_end = .;
+
+	.dynsym _image_binary_end : { *(.dynsym) }
+	.dynbss : { *(.dynbss) }
+	.dynstr : { *(.dynstr*) }
+	.dynamic : { *(.dynamic*) }
+	.hash : { *(.hash*) }
+	.plt : { *(.plt*) }
+	.interp : { *(.interp*) }
+	.gnu : { *(.gnu*) }
+	.ARM.exidx : { *(.ARM.exidx*) }
+}