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/of_address.h> 15 #include <linux/of_platform.h> 16 #include <linux/io.h> 17 18 #include <asm/mach/arch.h> 19 20 #include "kona_l2_cache.h" 21 22 #define RSTMGR_DT_STRING "brcm,bcm21664-resetmgr" 23 24 #define RSTMGR_REG_WR_ACCESS_OFFSET 0 25 #define RSTMGR_REG_CHIP_SOFT_RST_OFFSET 4 26 27 #define RSTMGR_WR_PASSWORD 0xa5a5 28 #define RSTMGR_WR_PASSWORD_SHIFT 8 29 #define RSTMGR_WR_ACCESS_ENABLE 1 30 31 static void bcm21664_restart(enum reboot_mode mode, const char *cmd) 32 { 33 void __iomem *base; 34 struct device_node *resetmgr; 35 36 resetmgr = of_find_compatible_node(NULL, NULL, RSTMGR_DT_STRING); 37 if (!resetmgr) { 38 pr_emerg("Couldn't find " RSTMGR_DT_STRING "\n"); 39 return; 40 } 41 base = of_iomap(resetmgr, 0); 42 if (!base) { 43 pr_emerg("Couldn't map " RSTMGR_DT_STRING "\n"); 44 return; 45 } 46 47 /* 48 * A soft reset is triggered by writing a 0 to bit 0 of the soft reset 49 * register. To write to that register we must first write the password 50 * and the enable bit in the write access enable register. 51 */ 52 writel((RSTMGR_WR_PASSWORD << RSTMGR_WR_PASSWORD_SHIFT) | 53 RSTMGR_WR_ACCESS_ENABLE, 54 base + RSTMGR_REG_WR_ACCESS_OFFSET); 55 writel(0, base + RSTMGR_REG_CHIP_SOFT_RST_OFFSET); 56 57 /* Wait for reset */ 58 while (1); 59 } 60 61 static void __init bcm21664_init(void) 62 { 63 of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL); 64 kona_l2_cache_init(); 65 } 66 67 static const char * const bcm21664_dt_compat[] = { 68 "brcm,bcm21664", 69 NULL, 70 }; 71 72 DT_MACHINE_START(BCM21664_DT, "BCM21664 Broadcom Application Processor") 73 .init_machine = bcm21664_init, 74 .restart = bcm21664_restart, 75 .dt_compat = bcm21664_dt_compat, 76 MACHINE_END 77