https://github.com/SourceLink/S5PV210

1、修改堆栈指针

vim include/configs/smdkv210.h 
#define CONFIG_SYS_LOAD_ADDR            CONFIG_SYS_SDRAM_BASE + 0x40000000              /* modied by Sourcelink */
#define CONFIG_SYS_INIT_SP_ADDR         CONFIG_SYS_LOAD_ADDR            		/* modied by Sourcelink */
#define CONFIG_SYS_SDRAM_BASE           0x20000000     					/* modied by Sourcelink */

2、添加串口

a）添加串口初始化引脚代码

vim board/samsung/smdkv210/lowlevel_init.S
        
ldr     r0, =0xE0200000
ldr     r1, =0X22222222
str     r1, [r0]

b）添加串口初始化配置代码

vim drivers/serial/serial_s5p.c

/*
 * (C) Copyright 2009 SAMSUNG Electronics
 * Minkyu Kang <[email protected]>
 * Heungjun Kim <[email protected]>
 *
 * based on drivers/serial/s3c64xx.c
 *
 * SPDX-License-Identifier:	GPL-2.0+
 */

#include <common.h>
#include <fdtdec.h>
#include <linux/compiler.h>
#include <asm/io.h>
#include <asm/arch/uart.h>
#include <asm/arch/clk.h>
#include <serial.h>

DECLARE_GLOBAL_DATA_PTR;

#define RX_FIFO_COUNT_MASK	0xff
#define RX_FIFO_FULL_MASK	(1 << 8)
#define TX_FIFO_FULL_MASK	(1 << 24)

/* Information about a serial port */
struct fdt_serial {
	u32 base_addr;  /* address of registers in physical memory */
	u8 port_id;     /* uart port number */
	u8 enabled;     /* 1 if enabled, 0 if disabled */
} config __attribute__ ((section(".data")));

static inline struct s5p_uart *s5p_get_base_uart(int dev_index)
{
#ifdef CONFIG_OF_CONTROL
	return (struct s5p_uart *)(config.base_addr);
#else
	u32 offset = dev_index * sizeof(struct s5p_uart);
	return (struct s5p_uart *)(samsung_get_base_uart() + offset);
#endif
}

/*
 * The coefficient, used to calculate the baudrate on S5P UARTs is
 * calculated as
 * C = UBRDIV * 16 + number_of_set_bits_in_UDIVSLOT
 * however, section 31.6.11 of the datasheet doesn't recomment using 1 for 1,
 * 3 for 2, ... (2^n - 1) for n, instead, they suggest using these constants:
 */
static const int udivslot[] = {
	0,
	0x0080,
	0x0808,
	0x0888,
	0x2222,
	0x4924,
	0x4a52,
	0x54aa,
	0x5555,
	0xd555,
	0xd5d5,
	0xddd5,
	0xdddd,
	0xdfdd,
	0xdfdf,
	0xffdf,
};

static void serial_setbrg_dev(const int dev_index)
{
	struct s5p_uart *const uart = s5p_get_base_uart(dev_index);
	u32 uclk = get_uart_clk(dev_index);
	u32 baudrate = gd->baudrate;
	u32 val;

#if defined(CONFIG_SILENT_CONSOLE) && \
		defined(CONFIG_OF_CONTROL) && \
		!defined(CONFIG_SPL_BUILD)
	if (fdtdec_get_config_int(gd->fdt_blob, "silent_console", 0))
		gd->flags |= GD_FLG_SILENT;
#endif

	if (!config.enabled)
		return;

	val = uclk / baudrate;

	writel(val / 16 - 1, &uart->ubrdiv);

	if (s5p_uart_divslot())
		writew(udivslot[val % 16], &uart->rest.slot);
	else
		writeb(val % 16, &uart->rest.value);
}

/*
 * Initialise the serial port with the given baudrate. The settings
 * are always 8 data bits, no parity, 1 stop bit, no start bits.
 */
static int serial_init_dev(const int dev_index)
{
	struct s5p_uart *const uart = s5p_get_base_uart(dev_index);

	/* enable FIFOs, auto clear Rx FIFO */
	writel(0x3, &uart->ufcon);
	writel(0, &uart->umcon);
	/* 8N1 */
	writel(0x3, &uart->ulcon);
	/* No interrupts, no DMA, pure polling */
	writel(0x245, &uart->ucon);

	serial_setbrg_dev(dev_index);

	return 0;
}

static int serial_err_check(const int dev_index, int op)
{
	struct s5p_uart *const uart = s5p_get_base_uart(dev_index);
	unsigned int mask;

	/*
	 * UERSTAT
	 * Break Detect	[3]
	 * Frame Err	[2] : receive operation
	 * Parity Err	[1] : receive operation
	 * Overrun Err	[0] : receive operation
	 */
	if (op)
		mask = 0x8;
	else
		mask = 0xf;

	return readl(&uart->uerstat) & mask;
}

/*
 * Read a single byte from the serial port. Returns 1 on success, 0
 * otherwise. When the function is succesfull, the character read is
 * written into its argument c.
 */
static int serial_getc_dev(const int dev_index)
{
	struct s5p_uart *const uart = s5p_get_base_uart(dev_index);

	if (!config.enabled)
		return 0;

	/* wait for character to arrive */
	while (!(readl(&uart->ufstat) & (RX_FIFO_COUNT_MASK |
					 RX_FIFO_FULL_MASK))) {
		if (serial_err_check(dev_index, 0))
			return 0;
	}

	return (int)(readb(&uart->urxh) & 0xff);
}

/*
 * Output a single byte to the serial port.
 */
static void serial_putc_dev(const char c, const int dev_index)
{
	struct s5p_uart *const uart = s5p_get_base_uart(dev_index);

	if (!config.enabled)
		return;

	/* wait for room in the tx FIFO */
	while ((readl(&uart->ufstat) & TX_FIFO_FULL_MASK)) {
		if (serial_err_check(dev_index, 1))
			return;
	}

	writeb(c, &uart->utxh);

	/* If \n, also do \r */
	if (c == '\n')
		serial_putc('\r');
}

/*
 * Test whether a character is in the RX buffer
 */
static int serial_tstc_dev(const int dev_index)
{
	struct s5p_uart *const uart = s5p_get_base_uart(dev_index);

	if (!config.enabled)
		return 0;

	return (int)(readl(&uart->utrstat) & 0x1);
}

static void serial_puts_dev(const char *s, const int dev_index)
{
	while (*s)
		serial_putc_dev(*s++, dev_index);
}

/* Multi serial device functions */
#define DECLARE_S5P_SERIAL_FUNCTIONS(port) \
static int s5p_serial##port##_init(void) { return serial_init_dev(port); } \
static void s5p_serial##port##_setbrg(void) { serial_setbrg_dev(port); } \
static int s5p_serial##port##_getc(void) { return serial_getc_dev(port); } \
static int s5p_serial##port##_tstc(void) { return serial_tstc_dev(port); } \
static void s5p_serial##port##_putc(const char c) { serial_putc_dev(c, port); } \
static void s5p_serial##port##_puts(const char *s) { serial_puts_dev(s, port); }

#define INIT_S5P_SERIAL_STRUCTURE(port, __name) {	\
	.name	= __name,				\
	.start	= s5p_serial##port##_init,		\
	.stop	= NULL,					\
	.setbrg	= s5p_serial##port##_setbrg,		\
	.getc	= s5p_serial##port##_getc,		\
	.tstc	= s5p_serial##port##_tstc,		\
	.putc	= s5p_serial##port##_putc,		\
	.puts	= s5p_serial##port##_puts,		\
}

DECLARE_S5P_SERIAL_FUNCTIONS(0);
struct serial_device s5p_serial0_device =
	INIT_S5P_SERIAL_STRUCTURE(0, "s5pser0");
DECLARE_S5P_SERIAL_FUNCTIONS(1);
struct serial_device s5p_serial1_device =
	INIT_S5P_SERIAL_STRUCTURE(1, "s5pser1");
DECLARE_S5P_SERIAL_FUNCTIONS(2);
struct serial_device s5p_serial2_device =
	INIT_S5P_SERIAL_STRUCTURE(2, "s5pser2");
DECLARE_S5P_SERIAL_FUNCTIONS(3);
struct serial_device s5p_serial3_device =
	INIT_S5P_SERIAL_STRUCTURE(3, "s5pser3");

#ifdef CONFIG_OF_CONTROL
int fdtdec_decode_console(int *index, struct fdt_serial *uart)
{
	const void *blob = gd->fdt_blob;
	int node;

	node = fdt_path_offset(blob, "console");
	if (node < 0)
		return node;

	uart->base_addr = fdtdec_get_addr(blob, node, "reg");
	if (uart->base_addr == FDT_ADDR_T_NONE)
		return -FDT_ERR_NOTFOUND;

	uart->port_id = fdtdec_get_int(blob, node, "id", -1);
	uart->enabled = fdtdec_get_is_enabled(blob, node);

	return 0;
}
#endif

__weak struct serial_device *default_serial_console(void)
{
#ifdef CONFIG_OF_CONTROL
	int index = 0;

	if ((!config.base_addr) && (fdtdec_decode_console(&index, &config))) {
		debug("Cannot decode default console node\n");
		return NULL;
	}

	switch (config.port_id) {
	case 0:
		return &s5p_serial0_device;
	case 1:
		return &s5p_serial1_device;
	case 2:
		return &s5p_serial2_device;
	case 3:
		return &s5p_serial3_device;
	default:
		debug("Unknown config.port_id: %d", config.port_id);
		break;
	}

	return NULL;
#else
	config.enabled = 1;
#if defined(CONFIG_SERIAL0)
	return &s5p_serial0_device;
#elif defined(CONFIG_SERIAL1)
	return &s5p_serial1_device;
#elif defined(CONFIG_SERIAL2)
	return &s5p_serial2_device;
#elif defined(CONFIG_SERIAL3)
	return &s5p_serial3_device;
#else
#error "CONFIG_SERIAL? missing."
#endif
#endif
}

void s5p_serial_initialize(void)
{
	serial_register(&s5p_serial0_device);
	serial_register(&s5p_serial1_device);
	serial_register(&s5p_serial2_device);
	serial_register(&s5p_serial3_device);
}

c）配置串口时钟

vim arch/arm/mach-s5pv210/clock.c

/* s5pv210: return PCLKs frequency */
static unsigned long get_pclk_sys(int dom)
{
        struct s5pv210_clock *clk =
                (struct s5pv210_clock *)samsung_get_base_clock();
        unsigned long pclk;
        unsigned int div;
        unsigned int offset;
        unsigned int pclk_sys_ratio;


        div = readl(&clk->div0);


        /*
         * PCLK_MSYS_RATIO: [14:12]
         * PCLK_DSYS_RATIO: [22:20]
         * PCLK_PSYS_RATIO: [30:28]
         */
        offset = 12 + (dom << 0x3);


        pclk_sys_ratio = (div >> offset) & 0x7;		/* modied by Sourcelink */


        pclk = get_hclk_sys(dom) / (pclk_sys_ratio + 1);


        return pclk;
}

/* s5pv210: return peripheral clock frequency */
static unsigned long s5pv210_get_pclk(void)
{
        /* modied by SOurcelink */
        return get_pclk_sys(CLK_P);
}


/* s5pv210: return uart clock frequency */
static unsigned long s5pv210_get_uart_clk(int dev_index)
{
        /* modied by SOurcelink */
        return s5pv210_get_pclk();
}

3、添加led指示灯

在上一篇文章分析过u-boot.bin初始化 可以自定义指示灯指示boot启动是否正常

#if ! defined(CONFIG_SPL_BUILD)
        bl coloured_LED_init
        bl red_led_on
#endif

vim common/board_f.c

__weak void coloured_LED_init(void) { *(volatile unsigned long*)0xE0200060 = 0x00011000;}	/* modied by Sourcelink */
__weak void red_led_on(void) {*(volatile unsigned long*)0xE0200064 = 0x00000018;}

4、添加输出信息

vim lib/display_options.c 

int display_options (void)
{
#if defined(BUILD_TAG)
        printf ("\n\n%s, Build: %s\n\n", version_string, BUILD_TAG);
#else
        printf ("\n\n%s\n\n", version_string);
#endif

        puts("Name : Sourcelink\n");    /* add by Sourcelink */
        puts("Email: [email protected]\n");

        return 0;
}

vim arch/arm/cpu/armv7/s5p-common/cpu_info.c 

#ifdef CONFIG_DISPLAY_CPUINFO
int print_cpuinfo(void)
{
        char buf[32];

        const char *cpu_model;
        int len;

        /* For SoC with no real CPU ID in naming convention. */
        cpu_model = fdt_getprop(gd->fdt_blob, 0, "cpu-model", &len);

        /* modied by Sourcelink */
        printf("CPU : %sV210@%sMHz \n", s5p_get_cpu_name(), strmhz(buf, get_arm_clk()));

        return 0;
}
#endif

5、更改时钟

vim arch/arm/mach-s5pv210/clock.c

/*
 * Copyright (C) 2009 Samsung Electronics
 * Minkyu Kang <[email protected]>
 * Heungjun Kim <[email protected]>
 *
 * SPDX-License-Identifier:	GPL-2.0+
 */

#include <common.h>
#include <asm/io.h>
#include <asm/arch/clock.h>
#include <asm/arch/clk.h>

#define CLK_M	0
#define CLK_D	1
#define CLK_P	2

/* modied by Sourcelink */
#ifndef CONFIG_SYS_CLK_FREQ_V210
#define CONFIG_SYS_CLK_FREQ_V210	12000000
#endif


/* s5pv210: return pll clock frequency (modied by Sourcelink) */
static unsigned long s5pv210_get_pll_clk(int pllreg)
{
	struct s5pv210_clock *clk =
		(struct s5pv210_clock *)samsung_get_base_clock();
	unsigned long r, m, p, s, mask, fout;
	unsigned int freq;

	switch (pllreg) {
	case APLL:
		r = readl(&clk->apll_con0);
		break;
	case MPLL:
		r = readl(&clk->mpll_con);
		break;
	case EPLL:
		r = readl(&clk->epll_con0);
		break;
	case VPLL:
		r = readl(&clk->vpll_con);
		break;
	default:
		printf("Unsupported PLL (%d)\n", pllreg);
		return 0;
	}

	/*
	 * APLL_CON: MIDV [25:16]
	 * MPLL_CON: MIDV [25:16]
	 * EPLL_CON: MIDV [24:16]
	 * VPLL_CON: MIDV [24:16]
	 */
	if (pllreg == APLL || pllreg == MPLL)
		mask = 0x3ff;
	else
		mask = 0x1ff;

	m = (r >> 16) & mask;

	/* PDIV [13:8] */
	p = (r >> 8) & 0x3f;
	/* SDIV [2:0] */
	s = r & 0x7;

	freq = CONFIG_SYS_CLK_FREQ_V210;
	if (pllreg == APLL) {
		if (s < 1)
			s = 1;
		/* FOUT = MDIV * FIN / (PDIV * 2^(SDIV - 1)) */
		fout = m * (freq / (p * (1 << (s - 1))));
	} else
		/* FOUT = MDIV * FIN / (PDIV * 2^SDIV) */
		fout = m * (freq / (p * (1 << s)));

	return fout;
}


/* s5pv210: return ARM clock frequency (modied by Sourcelink) */
static unsigned long s5pv210_get_arm_clk(void)
{
	struct s5pv210_clock *clk =
		(struct s5pv210_clock *)samsung_get_base_clock();
	unsigned long div;
	unsigned long dout_apll, armclk;
	unsigned int apll_ratio;

	div = readl(&clk->div0);

	/* ARM_RATIO: [2:0] */
	apll_ratio = div & 0x7;

	dout_apll = get_pll_clk(APLL) / (apll_ratio + 1);
	armclk = dout_apll;

	return armclk;
}

/* s5pv210: return HCLKD0 frequency */
static unsigned long get_hclk(void)
{
	struct s5pv210_clock *clk =
		(struct s5pv210_clock *)samsung_get_base_clock();
	unsigned long hclkd0;
	uint div, d0_bus_ratio;

	div = readl(&clk->div0);
	/* D0_BUS_RATIO: [10:8] */
	d0_bus_ratio = (div >> 8) & 0x7;

	hclkd0 = get_arm_clk() / (d0_bus_ratio + 1);

	return hclkd0;
}

/* s5pv210: return HCLKs frequency */
static unsigned long get_hclk_sys(int dom)
{
	struct s5pv210_clock *clk =
		(struct s5pv210_clock *)samsung_get_base_clock();
	unsigned long hclk;
	unsigned int div;
	unsigned int offset;
	unsigned int hclk_sys_ratio;

	if (dom == CLK_M)
		return get_hclk();

	div = readl(&clk->div0);

	/*
	 * HCLK_MSYS_RATIO: [10:8]
	 * HCLK_DSYS_RATIO: [19:16]
	 * HCLK_PSYS_RATIO: [27:24]
	 */
	offset = 8 + (dom << 0x3);

	hclk_sys_ratio = (div >> offset) & 0xf;

	hclk = get_pll_clk(MPLL) / (hclk_sys_ratio + 1);

	return hclk;
}

/* s5pv210: return PCLKs frequency */
static unsigned long get_pclk_sys(int dom)
{
	struct s5pv210_clock *clk =
		(struct s5pv210_clock *)samsung_get_base_clock();
	unsigned long pclk;
	unsigned int div;
	unsigned int offset;
	unsigned int pclk_sys_ratio;

	div = readl(&clk->div0);

	/*
	 * PCLK_MSYS_RATIO: [14:12]
	 * PCLK_DSYS_RATIO: [22:20]
	 * PCLK_PSYS_RATIO: [30:28]
	 */
	offset = 12 + (dom << 0x3);

	pclk_sys_ratio = (div >> offset) & 0x7;			/* moied by Sourcelink */

	pclk = get_hclk_sys(dom) / (pclk_sys_ratio + 1);

	return pclk;
}

/* s5pv210: return peripheral clock frequency */
static unsigned long s5pv210_get_pclk(void)
{	
	/* modied by SOurcelink */
	return get_pclk_sys(CLK_P);
}


/* s5pv210: return uart clock frequency */
static unsigned long s5pv210_get_uart_clk(int dev_index)
{
	/* modied by SOurcelink */
	return s5pv210_get_pclk();
}

/* s5pv21: return pwm clock frequency */
static unsigned long s5pv210_get_pwm_clk(void)
{
	/* modied by Sourcelink */
	return s5pv210_get_pclk();
}

unsigned long get_pll_clk(int pllreg)
{	
	/* modied by Sourcelink */
	return s5pv210_get_pll_clk(pllreg);
}

unsigned long get_arm_clk(void)
{
	/* modied by Sourcelink */
	return s5pv210_get_arm_clk();
}

unsigned long get_pwm_clk(void)
{
	/* modied by Sourcelink */
	return s5pv210_get_pwm_clk();
}

unsigned long get_uart_clk(int dev_index)
{
	/* modied by Sourcelink */
	return s5pv210_get_uart_clk(dev_index);
}

void set_mmc_clk(int dev_index, unsigned int div)
{
	/* Do NOTHING */
}

6、更改sd复制的扇区大小
vim board/samsung/smdkv210/smdkv210.c
CopySDMMCtoMem(ch, 32, 800, (unsigned int *)CONFIG_SYS_SDRAM_BASE, 0);

7、屏蔽onenand初始化

在完成前面那么多步骤后把u-boot.bin下载到第32扇区，smdkv210-spl.bin下载到第一扇区发现程序死在了NAND： 搜索NAND:后发现 ，是死了在onenand初始化故暂时屏蔽它。

vim common/board_r.c

#ifdef CONFIG_CMD_ONENAND
        //initr_onenand,                /* modied by Sourcelink */
#endif