1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * arch/arm/mach-tegra/reset.c
4 *
5 * Copyright (C) 2011,2012 NVIDIA Corporation.
6 */
7
8#include <linux/bitops.h>
9#include <linux/cpumask.h>
10#include <linux/init.h>
11#include <linux/io.h>
12
13#include <linux/firmware/trusted_foundations.h>
14
15#include <soc/tegra/fuse.h>
16
17#include <asm/cacheflush.h>
18#include <asm/firmware.h>
19#include <asm/hardware/cache-l2x0.h>
20
21#include "iomap.h"
22#include "irammap.h"
23#include "reset.h"
24#include "sleep.h"
25
26#define TEGRA_IRAM_RESET_BASE (TEGRA_IRAM_BASE + \
27 TEGRA_IRAM_RESET_HANDLER_OFFSET)
28
29static bool is_enabled;
30
31static void __init tegra_cpu_reset_handler_set(const u32 reset_address)
32{
33 void __iomem *evp_cpu_reset =
34 IO_ADDRESS(TEGRA_EXCEPTION_VECTORS_BASE + 0x100);
35 void __iomem *sb_ctrl = IO_ADDRESS(TEGRA_SB_BASE);
36 u32 reg;
37
38 /*
39 * NOTE: This must be the one and only write to the EVP CPU reset
40 * vector in the entire system.
41 */
42 writel(val: reset_address, addr: evp_cpu_reset);
43 wmb();
44 reg = readl(addr: evp_cpu_reset);
45
46 /*
47 * Prevent further modifications to the physical reset vector.
48 * NOTE: Has no effect on chips prior to Tegra30.
49 */
50 reg = readl(addr: sb_ctrl);
51 reg |= 2;
52 writel(val: reg, addr: sb_ctrl);
53 wmb();
54}
55
56static void __init tegra_cpu_reset_handler_enable(void)
57{
58 void __iomem *iram_base = IO_ADDRESS(TEGRA_IRAM_RESET_BASE);
59 const u32 reset_address = TEGRA_IRAM_RESET_BASE +
60 tegra_cpu_reset_handler_offset;
61 int err;
62
63 BUG_ON(is_enabled);
64 BUG_ON(tegra_cpu_reset_handler_size > TEGRA_IRAM_RESET_HANDLER_SIZE);
65
66 memcpy(iram_base, (void *)__tegra_cpu_reset_handler_start,
67 tegra_cpu_reset_handler_size);
68
69 err = call_firmware_op(set_cpu_boot_addr, 0, reset_address);
70 switch (err) {
71 case -ENOSYS:
72 tegra_cpu_reset_handler_set(reset_address);
73 fallthrough;
74 case 0:
75 is_enabled = true;
76 break;
77 default:
78 pr_crit("Cannot set CPU reset handler: %d\n", err);
79 BUG();
80 }
81}
82
83void __init tegra_cpu_reset_handler_init(void)
84{
85 __tegra_cpu_reset_handler_data[TEGRA_RESET_TF_PRESENT] =
86 trusted_foundations_registered();
87
88#ifdef CONFIG_SMP
89 __tegra_cpu_reset_handler_data[TEGRA_RESET_MASK_PRESENT] =
90 *((u32 *)cpu_possible_mask);
91 __tegra_cpu_reset_handler_data[TEGRA_RESET_STARTUP_SECONDARY] =
92 __pa_symbol((void *)secondary_startup);
93#endif
94
95#ifdef CONFIG_PM_SLEEP
96 __tegra_cpu_reset_handler_data[TEGRA_RESET_STARTUP_LP1] =
97 TEGRA_IRAM_LPx_RESUME_AREA;
98 __tegra_cpu_reset_handler_data[TEGRA_RESET_STARTUP_LP2] =
99 __pa_symbol((void *)tegra_resume);
100#endif
101
102 tegra_cpu_reset_handler_enable();
103}
104

source code of linux/arch/arm/mach-tegra/reset.c