1 /* 2 * arch/arm/mach-tegra/reset.c 3 * 4 * Copyright (C) 2011,2012 NVIDIA Corporation. 5 * 6 * This software is licensed under the terms of the GNU General Public 7 * License version 2, as published by the Free Software Foundation, and 8 * may be copied, distributed, and modified under those terms. 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU General Public License for more details. 14 * 15 */ 16 17 #include <linux/bitops.h> 18 #include <linux/cpumask.h> 19 #include <linux/init.h> 20 #include <linux/io.h> 21 22 #include <soc/tegra/fuse.h> 23 24 #include <asm/cacheflush.h> 25 #include <asm/firmware.h> 26 #include <asm/hardware/cache-l2x0.h> 27 28 #include "iomap.h" 29 #include "irammap.h" 30 #include "reset.h" 31 #include "sleep.h" 32 33 #define TEGRA_IRAM_RESET_BASE (TEGRA_IRAM_BASE + \ 34 TEGRA_IRAM_RESET_HANDLER_OFFSET) 35 36 static bool is_enabled; 37 38 static void __init tegra_cpu_reset_handler_set(const u32 reset_address) 39 { 40 void __iomem *evp_cpu_reset = 41 IO_ADDRESS(TEGRA_EXCEPTION_VECTORS_BASE + 0x100); 42 void __iomem *sb_ctrl = IO_ADDRESS(TEGRA_SB_BASE); 43 u32 reg; 44 45 /* 46 * NOTE: This must be the one and only write to the EVP CPU reset 47 * vector in the entire system. 48 */ 49 writel(reset_address, evp_cpu_reset); 50 wmb(); 51 reg = readl(evp_cpu_reset); 52 53 /* 54 * Prevent further modifications to the physical reset vector. 55 * NOTE: Has no effect on chips prior to Tegra30. 56 */ 57 reg = readl(sb_ctrl); 58 reg |= 2; 59 writel(reg, sb_ctrl); 60 wmb(); 61 } 62 63 static void __init tegra_cpu_reset_handler_enable(void) 64 { 65 void __iomem *iram_base = IO_ADDRESS(TEGRA_IRAM_RESET_BASE); 66 const u32 reset_address = TEGRA_IRAM_RESET_BASE + 67 tegra_cpu_reset_handler_offset; 68 int err; 69 70 BUG_ON(is_enabled); 71 BUG_ON(tegra_cpu_reset_handler_size > TEGRA_IRAM_RESET_HANDLER_SIZE); 72 73 memcpy(iram_base, (void *)__tegra_cpu_reset_handler_start, 74 tegra_cpu_reset_handler_size); 75 76 err = call_firmware_op(set_cpu_boot_addr, 0, reset_address); 77 switch (err) { 78 case -ENOSYS: 79 tegra_cpu_reset_handler_set(reset_address); 80 /* pass-through */ 81 case 0: 82 is_enabled = true; 83 break; 84 default: 85 pr_crit("Cannot set CPU reset handler: %d\n", err); 86 BUG(); 87 } 88 } 89 90 void __init tegra_cpu_reset_handler_init(void) 91 { 92 93 #ifdef CONFIG_SMP 94 __tegra_cpu_reset_handler_data[TEGRA_RESET_MASK_PRESENT] = 95 *((u32 *)cpu_possible_mask); 96 __tegra_cpu_reset_handler_data[TEGRA_RESET_STARTUP_SECONDARY] = 97 virt_to_phys((void *)tegra_secondary_startup); 98 #endif 99 100 #ifdef CONFIG_PM_SLEEP 101 __tegra_cpu_reset_handler_data[TEGRA_RESET_STARTUP_LP1] = 102 TEGRA_IRAM_LPx_RESUME_AREA; 103 __tegra_cpu_reset_handler_data[TEGRA_RESET_STARTUP_LP2] = 104 virt_to_phys((void *)tegra_resume); 105 #endif 106 107 tegra_cpu_reset_handler_enable(); 108 } 109