xref: /openbmc/u-boot/arch/arm/mach-bcm283x/reset.c (revision 76b00aca)
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 __efi_runtime_data struct bcm2835_wdog_regs *wdog_regs =
25 	(struct bcm2835_wdog_regs *)BCM2835_WDOG_PHYSADDR;
26 
27 void __efi_runtime reset_cpu(ulong addr)
28 {
29 	uint32_t rstc;
30 
31 	rstc = readl(&wdog_regs->rstc);
32 	rstc &= ~BCM2835_WDOG_RSTC_WRCFG_MASK;
33 	rstc |= BCM2835_WDOG_RSTC_WRCFG_FULL_RESET;
34 
35 	writel(BCM2835_WDOG_PASSWORD | RESET_TIMEOUT, &wdog_regs->wdog);
36 	writel(BCM2835_WDOG_PASSWORD | rstc, &wdog_regs->rstc);
37 }
38 
39 #ifdef CONFIG_EFI_LOADER
40 
41 void __efi_runtime EFIAPI efi_reset_system(
42 			enum efi_reset_type reset_type,
43 			efi_status_t reset_status,
44 			unsigned long data_size, void *reset_data)
45 {
46 	u32 val;
47 
48 	switch (reset_type) {
49 	case EFI_RESET_COLD:
50 	case EFI_RESET_WARM:
51 		reset_cpu(0);
52 		break;
53 	case EFI_RESET_SHUTDOWN:
54 		/*
55 		 * We set the watchdog hard reset bit here to distinguish this reset
56 		 * from the normal (full) reset. bootcode.bin will not reboot after a
57 		 * hard reset.
58 		 */
59 		val = readl(&wdog_regs->rsts);
60 		val |= BCM2835_WDOG_PASSWORD;
61 		val |= BCM2835_WDOG_RSTS_RASPBERRYPI_HALT;
62 		writel(val, &wdog_regs->rsts);
63 		reset_cpu(0);
64 		break;
65 	}
66 
67 	while (1) { }
68 }
69 
70 void efi_reset_system_init(void)
71 {
72 	efi_add_runtime_mmio(&wdog_regs, sizeof(*wdog_regs));
73 }
74 
75 #endif
76