xref: /openbmc/u-boot/arch/arm/mach-bcm283x/reset.c (revision a22bbfda)
1 /*
2  * (C) Copyright 2012 Stephen Warren
3  *
4  * See file CREDITS for list of people who contributed to this
5  * project.
6  *
7  * SPDX-License-Identifier:	GPL-2.0
8  */
9 
10 #include <common.h>
11 #include <asm/io.h>
12 #include <asm/arch/wdog.h>
13 #include <efi_loader.h>
14 
15 #define RESET_TIMEOUT 10
16 
17 /*
18  * The Raspberry Pi firmware uses the RSTS register to know which partiton
19  * to boot from. The partiton value is spread into bits 0, 2, 4, 6, 8, 10.
20  * Partiton 63 is a special partition used by the firmware to indicate halt.
21  */
22 #define BCM2835_WDOG_RSTS_RASPBERRYPI_HALT	0x555
23 
24 /* max ticks timeout */
25 #define BCM2835_WDOG_MAX_TIMEOUT	0x000fffff
26 
27 #ifdef CONFIG_BCM2835_WDT
28 extern void hw_watchdog_disable(void);
29 #else
30 void hw_watchdog_disable(void) {}
31 #endif
32 
33 __efi_runtime_data struct bcm2835_wdog_regs *wdog_regs =
34 	(struct bcm2835_wdog_regs *)BCM2835_WDOG_PHYSADDR;
35 
36 void __efi_runtime reset_cpu(ulong ticks)
37 {
38 	uint32_t rstc, timeout;
39 
40 	if (ticks == 0) {
41 		hw_watchdog_disable();
42 		timeout = RESET_TIMEOUT;
43 	} else
44 		timeout = ticks & BCM2835_WDOG_MAX_TIMEOUT;
45 
46 	rstc = readl(&wdog_regs->rstc);
47 	rstc &= ~BCM2835_WDOG_RSTC_WRCFG_MASK;
48 	rstc |= BCM2835_WDOG_RSTC_WRCFG_FULL_RESET;
49 
50 	writel(BCM2835_WDOG_PASSWORD | timeout, &wdog_regs->wdog);
51 	writel(BCM2835_WDOG_PASSWORD | rstc, &wdog_regs->rstc);
52 }
53 
54 #ifdef CONFIG_EFI_LOADER
55 
56 void __efi_runtime EFIAPI efi_reset_system(
57 			enum efi_reset_type reset_type,
58 			efi_status_t reset_status,
59 			unsigned long data_size, void *reset_data)
60 {
61 	u32 val;
62 
63 	switch (reset_type) {
64 	case EFI_RESET_COLD:
65 	case EFI_RESET_WARM:
66 		reset_cpu(0);
67 		break;
68 	case EFI_RESET_SHUTDOWN:
69 		/*
70 		 * We set the watchdog hard reset bit here to distinguish this reset
71 		 * from the normal (full) reset. bootcode.bin will not reboot after a
72 		 * hard reset.
73 		 */
74 		val = readl(&wdog_regs->rsts);
75 		val |= BCM2835_WDOG_PASSWORD;
76 		val |= BCM2835_WDOG_RSTS_RASPBERRYPI_HALT;
77 		writel(val, &wdog_regs->rsts);
78 		reset_cpu(0);
79 		break;
80 	}
81 
82 	while (1) { }
83 }
84 
85 void efi_reset_system_init(void)
86 {
87 	efi_add_runtime_mmio(&wdog_regs, sizeof(*wdog_regs));
88 }
89 
90 #endif
91