xref: /openbmc/u-boot/arch/arm/mach-at91/spl_at91.c (revision 29b103c7)
1 /*
2  * (C) Copyright 2014 DENX Software Engineering
3  *     Heiko Schocher <hs@denx.de>
4  *
5  * Based on:
6  * Copyright (C) 2013 Atmel Corporation
7  *		      Bo Shen <voice.shen@atmel.com>
8  *
9  * SPDX-License-Identifier:	GPL-2.0+
10  */
11 
12 #include <common.h>
13 #include <asm/io.h>
14 #include <asm/arch/at91_common.h>
15 #include <asm/arch/at91sam9_matrix.h>
16 #include <asm/arch/at91_pit.h>
17 #include <asm/arch/at91_pmc.h>
18 #include <asm/arch/at91_rstc.h>
19 #include <asm/arch/at91_wdt.h>
20 #include <asm/arch/clk.h>
21 #include <spl.h>
22 
23 DECLARE_GLOBAL_DATA_PTR;
24 
25 static void enable_ext_reset(void)
26 {
27 	struct at91_rstc *rstc = (struct at91_rstc *)ATMEL_BASE_RSTC;
28 
29 	writel(AT91_RSTC_KEY | AT91_RSTC_MR_URSTEN, &rstc->mr);
30 }
31 
32 void lowlevel_clock_init(void)
33 {
34 	struct at91_pmc *pmc = (struct at91_pmc *)ATMEL_BASE_PMC;
35 
36 	if (!(readl(&pmc->sr) & AT91_PMC_MOSCS)) {
37 		/* Enable Main Oscillator */
38 		writel(AT91_PMC_MOSCS | (0x40 << 8), &pmc->mor);
39 
40 		/* Wait until Main Oscillator is stable */
41 		while (!(readl(&pmc->sr) & AT91_PMC_MOSCS))
42 			;
43 	}
44 
45 	/* After stabilization, switch to Main Oscillator */
46 	if ((readl(&pmc->mckr) & AT91_PMC_CSS) == AT91_PMC_CSS_SLOW) {
47 		unsigned long tmp;
48 
49 		tmp = readl(&pmc->mckr);
50 		tmp &= ~AT91_PMC_CSS;
51 		tmp |= AT91_PMC_CSS_MAIN;
52 		writel(tmp, &pmc->mckr);
53 		while (!(readl(&pmc->sr) & AT91_PMC_MCKRDY))
54 			;
55 
56 		tmp &= ~AT91_PMC_PRES;
57 		tmp |= AT91_PMC_PRES_1;
58 		writel(tmp, &pmc->mckr);
59 		while (!(readl(&pmc->sr) & AT91_PMC_MCKRDY))
60 			;
61 	}
62 
63 	return;
64 }
65 
66 void __weak matrix_init(void)
67 {
68 }
69 
70 void __weak at91_spl_board_init(void)
71 {
72 }
73 
74 void __weak spl_board_init(void)
75 {
76 }
77 
78 void board_init_f(ulong dummy)
79 {
80 	struct at91_pmc *pmc = (struct at91_pmc *)ATMEL_BASE_PMC;
81 
82 	lowlevel_clock_init();
83 	at91_disable_wdt();
84 
85 	/*
86 	 * At this stage the main oscillator is supposed to be enabled
87 	 * PCK = MCK = MOSC
88 	 */
89 	writel(0x00, &pmc->pllicpr);
90 
91 	/* Configure PLLA = MOSC * (PLL_MULA + 1) / PLL_DIVA */
92 	at91_plla_init(CONFIG_SYS_AT91_PLLA);
93 
94 	/* PCK = PLLA = 2 * MCK */
95 	at91_mck_init(CONFIG_SYS_MCKR);
96 
97 	/* Switch MCK on PLLA output */
98 	at91_mck_init(CONFIG_SYS_MCKR_CSS);
99 
100 #if defined(CONFIG_SYS_AT91_PLLB)
101 	/* Configure PLLB */
102 	at91_pllb_init(CONFIG_SYS_AT91_PLLB);
103 #endif
104 
105 	/* Enable External Reset */
106 	enable_ext_reset();
107 
108 	/* Initialize matrix */
109 	matrix_init();
110 
111 	gd->arch.mck_rate_hz = CONFIG_SYS_MASTER_CLOCK;
112 	/*
113 	 * init timer long enough for using in spl.
114 	 */
115 	timer_init();
116 
117 	/* enable clocks for all PIOs */
118 #if defined(CONFIG_AT91SAM9X5) || defined(CONFIG_AT91SAM9N12)
119 	at91_periph_clk_enable(ATMEL_ID_PIOAB);
120 	at91_periph_clk_enable(ATMEL_ID_PIOCD);
121 #else
122 	at91_periph_clk_enable(ATMEL_ID_PIOA);
123 	at91_periph_clk_enable(ATMEL_ID_PIOB);
124 	at91_periph_clk_enable(ATMEL_ID_PIOC);
125 #endif
126 	/* init console */
127 	at91_seriald_hw_init();
128 	preloader_console_init();
129 
130 	mem_init();
131 
132 	at91_spl_board_init();
133 }
134