xref: /openbmc/u-boot/arch/arm/mach-at91/spl_atmel.c (revision ed09a554)
1 /*
2  * Copyright (C) 2013 Atmel Corporation
3  *		      Bo Shen <voice.shen@atmel.com>
4  *
5  * SPDX-License-Identifier:	GPL-2.0+
6  */
7 
8 #include <common.h>
9 #include <asm/io.h>
10 #include <asm/arch/at91_common.h>
11 #include <asm/arch/at91_pit.h>
12 #include <asm/arch/at91_pmc.h>
13 #include <asm/arch/at91_rstc.h>
14 #include <asm/arch/at91_wdt.h>
15 #include <asm/arch/clk.h>
16 #include <spl.h>
17 
18 DECLARE_GLOBAL_DATA_PTR;
19 
20 static void switch_to_main_crystal_osc(void)
21 {
22 	struct at91_pmc *pmc = (struct at91_pmc *)ATMEL_BASE_PMC;
23 	u32 tmp;
24 
25 	tmp = readl(&pmc->mor);
26 	tmp &= ~AT91_PMC_MOR_OSCOUNT(0xff);
27 	tmp &= ~AT91_PMC_MOR_KEY(0xff);
28 	tmp |= AT91_PMC_MOR_MOSCEN;
29 	tmp |= AT91_PMC_MOR_OSCOUNT(8);
30 	tmp |= AT91_PMC_MOR_KEY(0x37);
31 	writel(tmp, &pmc->mor);
32 	while (!(readl(&pmc->sr) & AT91_PMC_IXR_MOSCS))
33 		;
34 
35 	tmp = readl(&pmc->mor);
36 	tmp &= ~AT91_PMC_MOR_OSCBYPASS;
37 	tmp &= ~AT91_PMC_MOR_KEY(0xff);
38 	tmp |= AT91_PMC_MOR_KEY(0x37);
39 	writel(tmp, &pmc->mor);
40 
41 	tmp = readl(&pmc->mor);
42 	tmp |= AT91_PMC_MOR_MOSCSEL;
43 	tmp &= ~AT91_PMC_MOR_KEY(0xff);
44 	tmp |= AT91_PMC_MOR_KEY(0x37);
45 	writel(tmp, &pmc->mor);
46 
47 	while (!(readl(&pmc->sr) & AT91_PMC_IXR_MOSCSELS))
48 		;
49 
50 	/* Wait until MAINRDY field is set to make sure main clock is stable */
51 	while (!(readl(&pmc->mcfr) & AT91_PMC_MAINRDY))
52 		;
53 
54 #ifndef CONFIG_SAMA5D4
55 	tmp = readl(&pmc->mor);
56 	tmp &= ~AT91_PMC_MOR_MOSCRCEN;
57 	tmp &= ~AT91_PMC_MOR_KEY(0xff);
58 	tmp |= AT91_PMC_MOR_KEY(0x37);
59 	writel(tmp, &pmc->mor);
60 #endif
61 }
62 
63 __weak void matrix_init(void)
64 {
65 	/* This only be used for sama5d4 soc now */
66 }
67 
68 __weak void redirect_int_from_saic_to_aic(void)
69 {
70 	/* This only be used for sama5d4 soc now */
71 }
72 
73 /* empty stub to satisfy current lowlevel_init, can be removed any time */
74 void s_init(void)
75 {
76 }
77 
78 void board_init_f(ulong dummy)
79 {
80 	switch_to_main_crystal_osc();
81 
82 	/* disable watchdog */
83 	at91_disable_wdt();
84 
85 	/* PMC configuration */
86 	at91_pmc_init();
87 
88 	at91_clock_init(CONFIG_SYS_AT91_MAIN_CLOCK);
89 
90 	matrix_init();
91 
92 	redirect_int_from_saic_to_aic();
93 
94 	timer_init();
95 
96 	board_early_init_f();
97 
98 	preloader_console_init();
99 
100 	mem_init();
101 
102 	/* Clear the BSS. */
103 	memset(__bss_start, 0, __bss_end - __bss_start);
104 
105 	board_init_r(NULL, 0);
106 }
107