1 /* 2 * PowerNV setup code. 3 * 4 * Copyright 2011 IBM Corp. 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License 8 * as published by the Free Software Foundation; either version 9 * 2 of the License, or (at your option) any later version. 10 */ 11 12 #undef DEBUG 13 14 #include <linux/cpu.h> 15 #include <linux/errno.h> 16 #include <linux/sched.h> 17 #include <linux/kernel.h> 18 #include <linux/tty.h> 19 #include <linux/reboot.h> 20 #include <linux/init.h> 21 #include <linux/console.h> 22 #include <linux/delay.h> 23 #include <linux/irq.h> 24 #include <linux/seq_file.h> 25 #include <linux/of.h> 26 #include <linux/of_fdt.h> 27 #include <linux/interrupt.h> 28 #include <linux/bug.h> 29 #include <linux/pci.h> 30 #include <linux/cpufreq.h> 31 32 #include <asm/machdep.h> 33 #include <asm/firmware.h> 34 #include <asm/xics.h> 35 #include <asm/rtas.h> 36 #include <asm/opal.h> 37 #include <asm/kexec.h> 38 #include <asm/smp.h> 39 40 #include "powernv.h" 41 42 static void __init pnv_setup_arch(void) 43 { 44 set_arch_panic_timeout(10, ARCH_PANIC_TIMEOUT); 45 46 /* Initialize SMP */ 47 pnv_smp_init(); 48 49 /* Setup PCI */ 50 pnv_pci_init(); 51 52 /* Setup RTC and NVRAM callbacks */ 53 if (firmware_has_feature(FW_FEATURE_OPAL)) 54 opal_nvram_init(); 55 56 /* Enable NAP mode */ 57 powersave_nap = 1; 58 59 /* XXX PMCS */ 60 } 61 62 static void __init pnv_init_early(void) 63 { 64 /* 65 * Initialize the LPC bus now so that legacy serial 66 * ports can be found on it 67 */ 68 opal_lpc_init(); 69 70 #ifdef CONFIG_HVC_OPAL 71 if (firmware_has_feature(FW_FEATURE_OPAL)) 72 hvc_opal_init_early(); 73 else 74 #endif 75 add_preferred_console("hvc", 0, NULL); 76 } 77 78 static void __init pnv_init_IRQ(void) 79 { 80 xics_init(); 81 82 WARN_ON(!ppc_md.get_irq); 83 } 84 85 static void pnv_show_cpuinfo(struct seq_file *m) 86 { 87 struct device_node *root; 88 const char *model = ""; 89 90 root = of_find_node_by_path("/"); 91 if (root) 92 model = of_get_property(root, "model", NULL); 93 seq_printf(m, "machine\t\t: PowerNV %s\n", model); 94 if (firmware_has_feature(FW_FEATURE_OPALv3)) 95 seq_printf(m, "firmware\t: OPAL v3\n"); 96 else if (firmware_has_feature(FW_FEATURE_OPALv2)) 97 seq_printf(m, "firmware\t: OPAL v2\n"); 98 else if (firmware_has_feature(FW_FEATURE_OPAL)) 99 seq_printf(m, "firmware\t: OPAL v1\n"); 100 else 101 seq_printf(m, "firmware\t: BML\n"); 102 of_node_put(root); 103 } 104 105 static void pnv_prepare_going_down(void) 106 { 107 /* 108 * Disable all notifiers from OPAL, we can't 109 * service interrupts anymore anyway 110 */ 111 opal_notifier_disable(); 112 113 /* Soft disable interrupts */ 114 local_irq_disable(); 115 116 /* 117 * Return secondary CPUs to firwmare if a flash update 118 * is pending otherwise we will get all sort of error 119 * messages about CPU being stuck etc.. This will also 120 * have the side effect of hard disabling interrupts so 121 * past this point, the kernel is effectively dead. 122 */ 123 opal_flash_term_callback(); 124 } 125 126 static void __noreturn pnv_restart(char *cmd) 127 { 128 long rc = OPAL_BUSY; 129 130 pnv_prepare_going_down(); 131 132 while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) { 133 rc = opal_cec_reboot(); 134 if (rc == OPAL_BUSY_EVENT) 135 opal_poll_events(NULL); 136 else 137 mdelay(10); 138 } 139 for (;;) 140 opal_poll_events(NULL); 141 } 142 143 static void __noreturn pnv_power_off(void) 144 { 145 long rc = OPAL_BUSY; 146 147 pnv_prepare_going_down(); 148 149 while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) { 150 rc = opal_cec_power_down(0); 151 if (rc == OPAL_BUSY_EVENT) 152 opal_poll_events(NULL); 153 else 154 mdelay(10); 155 } 156 for (;;) 157 opal_poll_events(NULL); 158 } 159 160 static void __noreturn pnv_halt(void) 161 { 162 pnv_power_off(); 163 } 164 165 static void pnv_progress(char *s, unsigned short hex) 166 { 167 } 168 169 static int pnv_dma_set_mask(struct device *dev, u64 dma_mask) 170 { 171 if (dev_is_pci(dev)) 172 return pnv_pci_dma_set_mask(to_pci_dev(dev), dma_mask); 173 return __dma_set_mask(dev, dma_mask); 174 } 175 176 static void pnv_shutdown(void) 177 { 178 /* Let the PCI code clear up IODA tables */ 179 pnv_pci_shutdown(); 180 181 /* 182 * Stop OPAL activity: Unregister all OPAL interrupts so they 183 * don't fire up while we kexec and make sure all potentially 184 * DMA'ing ops are complete (such as dump retrieval). 185 */ 186 opal_shutdown(); 187 } 188 189 #ifdef CONFIG_KEXEC 190 static void pnv_kexec_wait_secondaries_down(void) 191 { 192 int my_cpu, i, notified = -1; 193 194 my_cpu = get_cpu(); 195 196 for_each_online_cpu(i) { 197 uint8_t status; 198 int64_t rc; 199 200 if (i == my_cpu) 201 continue; 202 203 for (;;) { 204 rc = opal_query_cpu_status(get_hard_smp_processor_id(i), 205 &status); 206 if (rc != OPAL_SUCCESS || status != OPAL_THREAD_STARTED) 207 break; 208 barrier(); 209 if (i != notified) { 210 printk(KERN_INFO "kexec: waiting for cpu %d " 211 "(physical %d) to enter OPAL\n", 212 i, paca[i].hw_cpu_id); 213 notified = i; 214 } 215 } 216 } 217 } 218 219 static void pnv_kexec_cpu_down(int crash_shutdown, int secondary) 220 { 221 xics_kexec_teardown_cpu(secondary); 222 223 /* On OPAL v3, we return all CPUs to firmware */ 224 225 if (!firmware_has_feature(FW_FEATURE_OPALv3)) 226 return; 227 228 if (secondary) { 229 /* Return secondary CPUs to firmware on OPAL v3 */ 230 mb(); 231 get_paca()->kexec_state = KEXEC_STATE_REAL_MODE; 232 mb(); 233 234 /* Return the CPU to OPAL */ 235 opal_return_cpu(); 236 } else if (crash_shutdown) { 237 /* 238 * On crash, we don't wait for secondaries to go 239 * down as they might be unreachable or hung, so 240 * instead we just wait a bit and move on. 241 */ 242 mdelay(1); 243 } else { 244 /* Primary waits for the secondaries to have reached OPAL */ 245 pnv_kexec_wait_secondaries_down(); 246 } 247 } 248 #endif /* CONFIG_KEXEC */ 249 250 #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE 251 static unsigned long pnv_memory_block_size(void) 252 { 253 return 256UL * 1024 * 1024; 254 } 255 #endif 256 257 static void __init pnv_setup_machdep_opal(void) 258 { 259 ppc_md.get_boot_time = opal_get_boot_time; 260 ppc_md.get_rtc_time = opal_get_rtc_time; 261 ppc_md.set_rtc_time = opal_set_rtc_time; 262 ppc_md.restart = pnv_restart; 263 ppc_md.power_off = pnv_power_off; 264 ppc_md.halt = pnv_halt; 265 ppc_md.machine_check_exception = opal_machine_check; 266 ppc_md.mce_check_early_recovery = opal_mce_check_early_recovery; 267 ppc_md.hmi_exception_early = opal_hmi_exception_early; 268 ppc_md.handle_hmi_exception = opal_handle_hmi_exception; 269 } 270 271 #ifdef CONFIG_PPC_POWERNV_RTAS 272 static void __init pnv_setup_machdep_rtas(void) 273 { 274 if (rtas_token("get-time-of-day") != RTAS_UNKNOWN_SERVICE) { 275 ppc_md.get_boot_time = rtas_get_boot_time; 276 ppc_md.get_rtc_time = rtas_get_rtc_time; 277 ppc_md.set_rtc_time = rtas_set_rtc_time; 278 } 279 ppc_md.restart = rtas_restart; 280 ppc_md.power_off = rtas_power_off; 281 ppc_md.halt = rtas_halt; 282 } 283 #endif /* CONFIG_PPC_POWERNV_RTAS */ 284 285 static int __init pnv_probe(void) 286 { 287 unsigned long root = of_get_flat_dt_root(); 288 289 if (!of_flat_dt_is_compatible(root, "ibm,powernv")) 290 return 0; 291 292 hpte_init_native(); 293 294 if (firmware_has_feature(FW_FEATURE_OPAL)) 295 pnv_setup_machdep_opal(); 296 #ifdef CONFIG_PPC_POWERNV_RTAS 297 else if (rtas.base) 298 pnv_setup_machdep_rtas(); 299 #endif /* CONFIG_PPC_POWERNV_RTAS */ 300 301 pr_debug("PowerNV detected !\n"); 302 303 return 1; 304 } 305 306 /* 307 * Returns the cpu frequency for 'cpu' in Hz. This is used by 308 * /proc/cpuinfo 309 */ 310 unsigned long pnv_get_proc_freq(unsigned int cpu) 311 { 312 unsigned long ret_freq; 313 314 ret_freq = cpufreq_quick_get(cpu) * 1000ul; 315 316 /* 317 * If the backend cpufreq driver does not exist, 318 * then fallback to old way of reporting the clockrate. 319 */ 320 if (!ret_freq) 321 ret_freq = ppc_proc_freq; 322 return ret_freq; 323 } 324 325 define_machine(powernv) { 326 .name = "PowerNV", 327 .probe = pnv_probe, 328 .init_early = pnv_init_early, 329 .setup_arch = pnv_setup_arch, 330 .init_IRQ = pnv_init_IRQ, 331 .show_cpuinfo = pnv_show_cpuinfo, 332 .get_proc_freq = pnv_get_proc_freq, 333 .progress = pnv_progress, 334 .machine_shutdown = pnv_shutdown, 335 .power_save = power7_idle, 336 .calibrate_decr = generic_calibrate_decr, 337 .dma_set_mask = pnv_dma_set_mask, 338 #ifdef CONFIG_KEXEC 339 .kexec_cpu_down = pnv_kexec_cpu_down, 340 #endif 341 #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE 342 .memory_block_size = pnv_memory_block_size, 343 #endif 344 }; 345