1 /* 2 * Copyright (C) 2014 Broadcom Corporation 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License as 6 * published by the Free Software Foundation version 2. 7 * 8 * This program is distributed "as is" WITHOUT ANY WARRANTY of any 9 * kind, whether express or implied; without even the implied warranty 10 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 11 * GNU General Public License for more details. 12 */ 13 14 #include <linux/clocksource.h> 15 #include <linux/of_address.h> 16 #include <linux/of_platform.h> 17 18 #include <asm/mach/arch.h> 19 20 #include "bcm_kona_smc.h" 21 #include "kona.h" 22 23 #define RSTMGR_DT_STRING "brcm,bcm21664-resetmgr" 24 25 #define RSTMGR_REG_WR_ACCESS_OFFSET 0 26 #define RSTMGR_REG_CHIP_SOFT_RST_OFFSET 4 27 28 #define RSTMGR_WR_PASSWORD 0xa5a5 29 #define RSTMGR_WR_PASSWORD_SHIFT 8 30 #define RSTMGR_WR_ACCESS_ENABLE 1 31 32 static void bcm21664_restart(enum reboot_mode mode, const char *cmd) 33 { 34 void __iomem *base; 35 struct device_node *resetmgr; 36 37 resetmgr = of_find_compatible_node(NULL, NULL, RSTMGR_DT_STRING); 38 if (!resetmgr) { 39 pr_emerg("Couldn't find " RSTMGR_DT_STRING "\n"); 40 return; 41 } 42 base = of_iomap(resetmgr, 0); 43 if (!base) { 44 pr_emerg("Couldn't map " RSTMGR_DT_STRING "\n"); 45 return; 46 } 47 48 /* 49 * A soft reset is triggered by writing a 0 to bit 0 of the soft reset 50 * register. To write to that register we must first write the password 51 * and the enable bit in the write access enable register. 52 */ 53 writel((RSTMGR_WR_PASSWORD << RSTMGR_WR_PASSWORD_SHIFT) | 54 RSTMGR_WR_ACCESS_ENABLE, 55 base + RSTMGR_REG_WR_ACCESS_OFFSET); 56 writel(0, base + RSTMGR_REG_CHIP_SOFT_RST_OFFSET); 57 58 /* Wait for reset */ 59 while (1); 60 } 61 62 static void __init bcm21664_init(void) 63 { 64 of_platform_populate(NULL, of_default_bus_match_table, NULL, 65 &platform_bus); 66 kona_l2_cache_init(); 67 } 68 69 static const char * const bcm21664_dt_compat[] = { 70 "brcm,bcm21664", 71 NULL, 72 }; 73 74 DT_MACHINE_START(BCM21664_DT, "BCM21664 Broadcom Application Processor") 75 .init_machine = bcm21664_init, 76 .restart = bcm21664_restart, 77 .dt_compat = bcm21664_dt_compat, 78 MACHINE_END 79