xref: /openbmc/u-boot/arch/arm/mach-at91/spl_at91.c (revision 8a23fc9c)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright 2014 DENX Software Engineering
4  *     Heiko Schocher <hs@denx.de>
5  *
6  * Based on:
7  * Copyright (C) 2013 Atmel Corporation
8  *		      Bo Shen <voice.shen@atmel.com>
9  */
10 
11 #include <common.h>
12 #include <asm/io.h>
13 #include <asm/arch/at91_common.h>
14 #include <asm/arch/at91sam9_matrix.h>
15 #include <asm/arch/at91_pit.h>
16 #include <asm/arch/at91_rstc.h>
17 #include <asm/arch/at91_wdt.h>
18 #include <asm/arch/clk.h>
19 #include <spl.h>
20 
21 DECLARE_GLOBAL_DATA_PTR;
22 
23 static void enable_ext_reset(void)
24 {
25 	struct at91_rstc *rstc = (struct at91_rstc *)ATMEL_BASE_RSTC;
26 
27 	writel(AT91_RSTC_KEY | AT91_RSTC_MR_URSTEN, &rstc->mr);
28 }
29 
30 void lowlevel_clock_init(void)
31 {
32 	struct at91_pmc *pmc = (struct at91_pmc *)ATMEL_BASE_PMC;
33 
34 	if (!(readl(&pmc->sr) & AT91_PMC_MOSCS)) {
35 		/* Enable Main Oscillator */
36 		writel(AT91_PMC_MOSCS | (0x40 << 8), &pmc->mor);
37 
38 		/* Wait until Main Oscillator is stable */
39 		while (!(readl(&pmc->sr) & AT91_PMC_MOSCS))
40 			;
41 	}
42 
43 	/* After stabilization, switch to Main Oscillator */
44 	if ((readl(&pmc->mckr) & AT91_PMC_CSS) == AT91_PMC_CSS_SLOW) {
45 		unsigned long tmp;
46 
47 		tmp = readl(&pmc->mckr);
48 		tmp &= ~AT91_PMC_CSS;
49 		tmp |= AT91_PMC_CSS_MAIN;
50 		writel(tmp, &pmc->mckr);
51 		while (!(readl(&pmc->sr) & AT91_PMC_MCKRDY))
52 			;
53 
54 		tmp &= ~AT91_PMC_PRES;
55 		tmp |= AT91_PMC_PRES_1;
56 		writel(tmp, &pmc->mckr);
57 		while (!(readl(&pmc->sr) & AT91_PMC_MCKRDY))
58 			;
59 	}
60 
61 	return;
62 }
63 
64 void __weak matrix_init(void)
65 {
66 }
67 
68 void __weak at91_spl_board_init(void)
69 {
70 }
71 
72 void __weak spl_board_init(void)
73 {
74 }
75 
76 void board_init_f(ulong dummy)
77 {
78 	lowlevel_clock_init();
79 #if !defined(CONFIG_WDT_AT91)
80 	at91_disable_wdt();
81 #endif
82 
83 	/*
84 	 * At this stage the main oscillator is supposed to be enabled
85 	 * PCK = MCK = MOSC
86 	 */
87 	at91_pllicpr_init(0x00);
88 
89 	/* Configure PLLA = MOSC * (PLL_MULA + 1) / PLL_DIVA */
90 	at91_plla_init(CONFIG_SYS_AT91_PLLA);
91 
92 	/* PCK = PLLA = 2 * MCK */
93 	at91_mck_init(CONFIG_SYS_MCKR);
94 
95 	/* Switch MCK on PLLA output */
96 	at91_mck_init(CONFIG_SYS_MCKR_CSS);
97 
98 #if defined(CONFIG_SYS_AT91_PLLB)
99 	/* Configure PLLB */
100 	at91_pllb_init(CONFIG_SYS_AT91_PLLB);
101 #endif
102 
103 	/* Enable External Reset */
104 	enable_ext_reset();
105 
106 	/* Initialize matrix */
107 	matrix_init();
108 
109 	gd->arch.mck_rate_hz = CONFIG_SYS_MASTER_CLOCK;
110 	/*
111 	 * init timer long enough for using in spl.
112 	 */
113 	timer_init();
114 
115 	/* enable clocks for all PIOs */
116 #if defined(CONFIG_AT91SAM9X5) || defined(CONFIG_AT91SAM9N12)
117 	at91_periph_clk_enable(ATMEL_ID_PIOAB);
118 	at91_periph_clk_enable(ATMEL_ID_PIOCD);
119 #else
120 	at91_periph_clk_enable(ATMEL_ID_PIOA);
121 	at91_periph_clk_enable(ATMEL_ID_PIOB);
122 	at91_periph_clk_enable(ATMEL_ID_PIOC);
123 #endif
124 
125 #if defined(CONFIG_SPL_SERIAL_SUPPORT)
126 	/* init console */
127 	at91_seriald_hw_init();
128 	preloader_console_init();
129 #endif
130 
131 	mem_init();
132 
133 	at91_spl_board_init();
134 }
135