xref: /openbmc/u-boot/arch/arm/mach-at91/spl_at91.c (revision b24a8ec1)
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_rstc.h>
18 #include <asm/arch/at91_wdt.h>
19 #include <asm/arch/clk.h>
20 #include <spl.h>
21 
22 DECLARE_GLOBAL_DATA_PTR;
23 
24 static void enable_ext_reset(void)
25 {
26 	struct at91_rstc *rstc = (struct at91_rstc *)ATMEL_BASE_RSTC;
27 
28 	writel(AT91_RSTC_KEY | AT91_RSTC_MR_URSTEN, &rstc->mr);
29 }
30 
31 void lowlevel_clock_init(void)
32 {
33 	struct at91_pmc *pmc = (struct at91_pmc *)ATMEL_BASE_PMC;
34 
35 	if (!(readl(&pmc->sr) & AT91_PMC_MOSCS)) {
36 		/* Enable Main Oscillator */
37 		writel(AT91_PMC_MOSCS | (0x40 << 8), &pmc->mor);
38 
39 		/* Wait until Main Oscillator is stable */
40 		while (!(readl(&pmc->sr) & AT91_PMC_MOSCS))
41 			;
42 	}
43 
44 	/* After stabilization, switch to Main Oscillator */
45 	if ((readl(&pmc->mckr) & AT91_PMC_CSS) == AT91_PMC_CSS_SLOW) {
46 		unsigned long tmp;
47 
48 		tmp = readl(&pmc->mckr);
49 		tmp &= ~AT91_PMC_CSS;
50 		tmp |= AT91_PMC_CSS_MAIN;
51 		writel(tmp, &pmc->mckr);
52 		while (!(readl(&pmc->sr) & AT91_PMC_MCKRDY))
53 			;
54 
55 		tmp &= ~AT91_PMC_PRES;
56 		tmp |= AT91_PMC_PRES_1;
57 		writel(tmp, &pmc->mckr);
58 		while (!(readl(&pmc->sr) & AT91_PMC_MCKRDY))
59 			;
60 	}
61 
62 	return;
63 }
64 
65 void __weak matrix_init(void)
66 {
67 }
68 
69 void __weak at91_spl_board_init(void)
70 {
71 }
72 
73 void __weak spl_board_init(void)
74 {
75 }
76 
77 void board_init_f(ulong dummy)
78 {
79 	lowlevel_clock_init();
80 	at91_disable_wdt();
81 
82 	/*
83 	 * At this stage the main oscillator is supposed to be enabled
84 	 * PCK = MCK = MOSC
85 	 */
86 	at91_pllicpr_init(0x00);
87 
88 	/* Configure PLLA = MOSC * (PLL_MULA + 1) / PLL_DIVA */
89 	at91_plla_init(CONFIG_SYS_AT91_PLLA);
90 
91 	/* PCK = PLLA = 2 * MCK */
92 	at91_mck_init(CONFIG_SYS_MCKR);
93 
94 	/* Switch MCK on PLLA output */
95 	at91_mck_init(CONFIG_SYS_MCKR_CSS);
96 
97 #if defined(CONFIG_SYS_AT91_PLLB)
98 	/* Configure PLLB */
99 	at91_pllb_init(CONFIG_SYS_AT91_PLLB);
100 #endif
101 
102 	/* Enable External Reset */
103 	enable_ext_reset();
104 
105 	/* Initialize matrix */
106 	matrix_init();
107 
108 	gd->arch.mck_rate_hz = CONFIG_SYS_MASTER_CLOCK;
109 	/*
110 	 * init timer long enough for using in spl.
111 	 */
112 	timer_init();
113 
114 	/* enable clocks for all PIOs */
115 #if defined(CONFIG_AT91SAM9X5) || defined(CONFIG_AT91SAM9N12)
116 	at91_periph_clk_enable(ATMEL_ID_PIOAB);
117 	at91_periph_clk_enable(ATMEL_ID_PIOCD);
118 #else
119 	at91_periph_clk_enable(ATMEL_ID_PIOA);
120 	at91_periph_clk_enable(ATMEL_ID_PIOB);
121 	at91_periph_clk_enable(ATMEL_ID_PIOC);
122 #endif
123 
124 #if defined(CONFIG_SPL_SERIAL_SUPPORT)
125 	/* init console */
126 	at91_seriald_hw_init();
127 	preloader_console_init();
128 #endif
129 
130 	mem_init();
131 
132 	at91_spl_board_init();
133 }
134