1 /* 2 * This file is subject to the terms and conditions of the GNU General Public 3 * License. See the file "COPYING" in the main directory of this archive 4 * for more details. 5 * 6 * Copyright (C) 2008 Maxime Bizon <mbizon@freebox.fr> 7 * Copyright (C) 2014 Kevin Cernekee <cernekee@gmail.com> 8 */ 9 10 #include <linux/init.h> 11 #include <linux/bitops.h> 12 #include <linux/bootmem.h> 13 #include <linux/clk-provider.h> 14 #include <linux/ioport.h> 15 #include <linux/kernel.h> 16 #include <linux/io.h> 17 #include <linux/of.h> 18 #include <linux/of_fdt.h> 19 #include <linux/of_platform.h> 20 #include <linux/smp.h> 21 #include <asm/addrspace.h> 22 #include <asm/bmips.h> 23 #include <asm/bootinfo.h> 24 #include <asm/cpu-type.h> 25 #include <asm/mipsregs.h> 26 #include <asm/prom.h> 27 #include <asm/smp-ops.h> 28 #include <asm/time.h> 29 #include <asm/traps.h> 30 31 #define RELO_NORMAL_VEC BIT(18) 32 33 #define REG_BCM6328_OTP ((void __iomem *)CKSEG1ADDR(0x1000062c)) 34 #define BCM6328_TP1_DISABLED BIT(9) 35 36 static const unsigned long kbase = VMLINUX_LOAD_ADDRESS & 0xfff00000; 37 38 struct bmips_quirk { 39 const char *compatible; 40 void (*quirk_fn)(void); 41 }; 42 43 static void kbase_setup(void) 44 { 45 __raw_writel(kbase | RELO_NORMAL_VEC, 46 BMIPS_GET_CBR() + BMIPS_RELO_VECTOR_CONTROL_1); 47 ebase = kbase; 48 } 49 50 static void bcm3384_viper_quirks(void) 51 { 52 /* 53 * Some experimental CM boxes are set up to let CM own the Viper TP0 54 * and let Linux own TP1. This requires moving the kernel 55 * load address to a non-conflicting region (e.g. via 56 * CONFIG_PHYSICAL_START) and supplying an alternate DTB. 57 * If we detect this condition, we need to move the MIPS exception 58 * vectors up to an area that we own. 59 * 60 * This is distinct from the OTHER special case mentioned in 61 * smp-bmips.c (boot on TP1, but enable SMP, then TP0 becomes our 62 * logical CPU#1). For the Viper TP1 case, SMP is off limits. 63 * 64 * Also note that many BMIPS435x CPUs do not have a 65 * BMIPS_RELO_VECTOR_CONTROL_1 register, so it isn't safe to just 66 * write VMLINUX_LOAD_ADDRESS into that register on every SoC. 67 */ 68 board_ebase_setup = &kbase_setup; 69 bmips_smp_enabled = 0; 70 } 71 72 static void bcm63xx_fixup_cpu1(void) 73 { 74 /* 75 * The bootloader has set up the CPU1 reset vector at 76 * 0xa000_0200. 77 * This conflicts with the special interrupt vector (IV). 78 * The bootloader has also set up CPU1 to respond to the wrong 79 * IPI interrupt. 80 * Here we will start up CPU1 in the background and ask it to 81 * reconfigure itself then go back to sleep. 82 */ 83 memcpy((void *)0xa0000200, &bmips_smp_movevec, 0x20); 84 __sync(); 85 set_c0_cause(C_SW0); 86 cpumask_set_cpu(1, &bmips_booted_mask); 87 } 88 89 static void bcm6328_quirks(void) 90 { 91 /* Check CPU1 status in OTP (it is usually disabled) */ 92 if (__raw_readl(REG_BCM6328_OTP) & BCM6328_TP1_DISABLED) 93 bmips_smp_enabled = 0; 94 else 95 bcm63xx_fixup_cpu1(); 96 } 97 98 static void bcm6358_quirks(void) 99 { 100 /* 101 * BCM6358 needs special handling for its shared TLB, so 102 * disable SMP for now 103 */ 104 bmips_smp_enabled = 0; 105 } 106 107 static void bcm6368_quirks(void) 108 { 109 bcm63xx_fixup_cpu1(); 110 } 111 112 static const struct bmips_quirk bmips_quirk_list[] = { 113 { "brcm,bcm3384-viper", &bcm3384_viper_quirks }, 114 { "brcm,bcm33843-viper", &bcm3384_viper_quirks }, 115 { "brcm,bcm6328", &bcm6328_quirks }, 116 { "brcm,bcm6358", &bcm6358_quirks }, 117 { "brcm,bcm6368", &bcm6368_quirks }, 118 { "brcm,bcm63168", &bcm6368_quirks }, 119 { }, 120 }; 121 122 void __init prom_init(void) 123 { 124 bmips_cpu_setup(); 125 register_bmips_smp_ops(); 126 } 127 128 void __init prom_free_prom_memory(void) 129 { 130 } 131 132 const char *get_system_type(void) 133 { 134 return "Generic BMIPS kernel"; 135 } 136 137 void __init plat_time_init(void) 138 { 139 struct device_node *np; 140 u32 freq; 141 142 np = of_find_node_by_name(NULL, "cpus"); 143 if (!np) 144 panic("missing 'cpus' DT node"); 145 if (of_property_read_u32(np, "mips-hpt-frequency", &freq) < 0) 146 panic("missing 'mips-hpt-frequency' property"); 147 of_node_put(np); 148 149 mips_hpt_frequency = freq; 150 } 151 152 void __init plat_mem_setup(void) 153 { 154 void *dtb; 155 const struct bmips_quirk *q; 156 157 set_io_port_base(0); 158 ioport_resource.start = 0; 159 ioport_resource.end = ~0; 160 161 /* intended to somewhat resemble ARM; see Documentation/arm/Booting */ 162 if (fw_arg0 == 0 && fw_arg1 == 0xffffffff) 163 dtb = phys_to_virt(fw_arg2); 164 else if (fw_arg0 == -2) /* UHI interface */ 165 dtb = (void *)fw_arg1; 166 else if (__dtb_start != __dtb_end) 167 dtb = (void *)__dtb_start; 168 else 169 panic("no dtb found"); 170 171 __dt_setup_arch(dtb); 172 173 for (q = bmips_quirk_list; q->quirk_fn; q++) { 174 if (of_flat_dt_is_compatible(of_get_flat_dt_root(), 175 q->compatible)) { 176 q->quirk_fn(); 177 } 178 } 179 } 180 181 void __init device_tree_init(void) 182 { 183 struct device_node *np; 184 185 unflatten_and_copy_device_tree(); 186 187 /* Disable SMP boot unless both CPUs are listed in DT and !disabled */ 188 np = of_find_node_by_name(NULL, "cpus"); 189 if (np && of_get_available_child_count(np) <= 1) 190 bmips_smp_enabled = 0; 191 of_node_put(np); 192 } 193 194 int __init plat_of_setup(void) 195 { 196 return __dt_register_buses("simple-bus", NULL); 197 } 198 199 arch_initcall(plat_of_setup); 200 201 static int __init plat_dev_init(void) 202 { 203 of_clk_init(NULL); 204 return 0; 205 } 206 207 device_initcall(plat_dev_init); 208