4 * Copyright (C) Linaro.
5 * Copyright (C) Huawei Futurewei Technologies.
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
12 #include <linux/interrupt.h>
13 #include <linux/irq.h>
14 #include <linux/kernel.h>
15 #include <linux/kexec.h>
16 #include <linux/page-flags.h>
17 #include <linux/smp.h>
19 #include <asm/cacheflush.h>
20 #include <asm/cpu_ops.h>
21 #include <asm/memory.h>
23 #include <asm/mmu_context.h>
26 #include "cpu-reset.h"
28 /* Global variables for the arm64_relocate_new_kernel routine. */
29 extern const unsigned char arm64_relocate_new_kernel[];
30 extern const unsigned long arm64_relocate_new_kernel_size;
33 * kexec_image_info - For debugging output.
35 #define kexec_image_info(_i) _kexec_image_info(__func__, __LINE__, _i)
36 static void _kexec_image_info(const char *func, int line,
37 const struct kimage *kimage)
41 pr_debug("%s:%d:\n", func, line);
42 pr_debug(" kexec kimage info:\n");
43 pr_debug(" type: %d\n", kimage->type);
44 pr_debug(" start: %lx\n", kimage->start);
45 pr_debug(" head: %lx\n", kimage->head);
46 pr_debug(" nr_segments: %lu\n", kimage->nr_segments);
48 for (i = 0; i < kimage->nr_segments; i++) {
49 pr_debug(" segment[%lu]: %016lx - %016lx, 0x%lx bytes, %lu pages\n",
51 kimage->segment[i].mem,
52 kimage->segment[i].mem + kimage->segment[i].memsz,
53 kimage->segment[i].memsz,
54 kimage->segment[i].memsz / PAGE_SIZE);
58 void machine_kexec_cleanup(struct kimage *kimage)
60 /* Empty routine needed to avoid build errors. */
64 * machine_kexec_prepare - Prepare for a kexec reboot.
66 * Called from the core kexec code when a kernel image is loaded.
67 * Forbid loading a kexec kernel if we have no way of hotplugging cpus or cpus
68 * are stuck in the kernel. This avoids a panic once we hit machine_kexec().
70 int machine_kexec_prepare(struct kimage *kimage)
72 kexec_image_info(kimage);
74 if (kimage->type != KEXEC_TYPE_CRASH && cpus_are_stuck_in_kernel()) {
75 pr_err("Can't kexec: CPUs are stuck in the kernel.\n");
83 * kexec_list_flush - Helper to flush the kimage list and source pages to PoC.
85 static void kexec_list_flush(struct kimage *kimage)
87 kimage_entry_t *entry;
89 for (entry = &kimage->head; ; entry++) {
93 /* flush the list entries. */
94 __flush_dcache_area(entry, sizeof(kimage_entry_t));
96 flag = *entry & IND_FLAGS;
100 addr = phys_to_virt(*entry & PAGE_MASK);
103 case IND_INDIRECTION:
104 /* Set entry point just before the new list page. */
105 entry = (kimage_entry_t *)addr - 1;
108 /* flush the source pages. */
109 __flush_dcache_area(addr, PAGE_SIZE);
111 case IND_DESTINATION:
120 * kexec_segment_flush - Helper to flush the kimage segments to PoC.
122 static void kexec_segment_flush(const struct kimage *kimage)
126 pr_debug("%s:\n", __func__);
128 for (i = 0; i < kimage->nr_segments; i++) {
129 pr_debug(" segment[%lu]: %016lx - %016lx, 0x%lx bytes, %lu pages\n",
131 kimage->segment[i].mem,
132 kimage->segment[i].mem + kimage->segment[i].memsz,
133 kimage->segment[i].memsz,
134 kimage->segment[i].memsz / PAGE_SIZE);
136 __flush_dcache_area(phys_to_virt(kimage->segment[i].mem),
137 kimage->segment[i].memsz);
142 * machine_kexec - Do the kexec reboot.
144 * Called from the core kexec code for a sys_reboot with LINUX_REBOOT_CMD_KEXEC.
146 void machine_kexec(struct kimage *kimage)
148 phys_addr_t reboot_code_buffer_phys;
149 void *reboot_code_buffer;
150 bool in_kexec_crash = (kimage == kexec_crash_image);
151 bool stuck_cpus = cpus_are_stuck_in_kernel();
154 * New cpus may have become stuck_in_kernel after we loaded the image.
156 BUG_ON(!in_kexec_crash && (stuck_cpus || (num_online_cpus() > 1)));
157 WARN(in_kexec_crash && (stuck_cpus || smp_crash_stop_failed()),
158 "Some CPUs may be stale, kdump will be unreliable.\n");
160 reboot_code_buffer_phys = page_to_phys(kimage->control_code_page);
161 reboot_code_buffer = phys_to_virt(reboot_code_buffer_phys);
163 kexec_image_info(kimage);
165 pr_debug("%s:%d: control_code_page: %p\n", __func__, __LINE__,
166 kimage->control_code_page);
167 pr_debug("%s:%d: reboot_code_buffer_phys: %pa\n", __func__, __LINE__,
168 &reboot_code_buffer_phys);
169 pr_debug("%s:%d: reboot_code_buffer: %p\n", __func__, __LINE__,
171 pr_debug("%s:%d: relocate_new_kernel: %p\n", __func__, __LINE__,
172 arm64_relocate_new_kernel);
173 pr_debug("%s:%d: relocate_new_kernel_size: 0x%lx(%lu) bytes\n",
174 __func__, __LINE__, arm64_relocate_new_kernel_size,
175 arm64_relocate_new_kernel_size);
178 * Copy arm64_relocate_new_kernel to the reboot_code_buffer for use
179 * after the kernel is shut down.
181 memcpy(reboot_code_buffer, arm64_relocate_new_kernel,
182 arm64_relocate_new_kernel_size);
184 /* Flush the reboot_code_buffer in preparation for its execution. */
185 __flush_dcache_area(reboot_code_buffer, arm64_relocate_new_kernel_size);
186 flush_icache_range((uintptr_t)reboot_code_buffer,
187 (uintptr_t)reboot_code_buffer +
188 arm64_relocate_new_kernel_size);
190 /* Flush the kimage list and its buffers. */
191 kexec_list_flush(kimage);
193 /* Flush the new image if already in place. */
194 if ((kimage != kexec_crash_image) && (kimage->head & IND_DONE))
195 kexec_segment_flush(kimage);
199 /* Disable all DAIF exceptions. */
200 asm volatile ("msr daifset, #0xf" : : : "memory");
203 * cpu_soft_restart will shutdown the MMU, disable data caches, then
204 * transfer control to the reboot_code_buffer which contains a copy of
205 * the arm64_relocate_new_kernel routine. arm64_relocate_new_kernel
206 * uses physical addressing to relocate the new image to its final
207 * position and transfers control to the image entry point when the
208 * relocation is complete.
211 cpu_soft_restart(kimage != kexec_crash_image,
212 reboot_code_buffer_phys, kimage->head, kimage->start, 0);
214 BUG(); /* Should never get here. */
217 static void machine_kexec_mask_interrupts(void)
220 struct irq_desc *desc;
222 for_each_irq_desc(i, desc) {
223 struct irq_chip *chip;
226 chip = irq_desc_get_chip(desc);
231 * First try to remove the active state. If this
232 * fails, try to EOI the interrupt.
234 ret = irq_set_irqchip_state(i, IRQCHIP_STATE_ACTIVE, false);
236 if (ret && irqd_irq_inprogress(&desc->irq_data) &&
238 chip->irq_eoi(&desc->irq_data);
241 chip->irq_mask(&desc->irq_data);
243 if (chip->irq_disable && !irqd_irq_disabled(&desc->irq_data))
244 chip->irq_disable(&desc->irq_data);
249 * machine_crash_shutdown - shutdown non-crashing cpus and save registers
251 void machine_crash_shutdown(struct pt_regs *regs)
255 /* shutdown non-crashing cpus */
256 crash_smp_send_stop();
258 /* for crashing cpu */
259 crash_save_cpu(regs, smp_processor_id());
260 machine_kexec_mask_interrupts();
262 pr_info("Starting crashdump kernel...\n");
265 void arch_kexec_protect_crashkres(void)
269 kexec_segment_flush(kexec_crash_image);
271 for (i = 0; i < kexec_crash_image->nr_segments; i++)
273 __phys_to_virt(kexec_crash_image->segment[i].mem),
274 kexec_crash_image->segment[i].memsz >> PAGE_SHIFT, 0);
277 void arch_kexec_unprotect_crashkres(void)
281 for (i = 0; i < kexec_crash_image->nr_segments; i++)
283 __phys_to_virt(kexec_crash_image->segment[i].mem),
284 kexec_crash_image->segment[i].memsz >> PAGE_SHIFT, 1);
287 #ifdef CONFIG_HIBERNATION
289 * To preserve the crash dump kernel image, the relevant memory segments
290 * should be mapped again around the hibernation.
292 void crash_prepare_suspend(void)
294 if (kexec_crash_image)
295 arch_kexec_unprotect_crashkres();
298 void crash_post_resume(void)
300 if (kexec_crash_image)
301 arch_kexec_protect_crashkres();
307 * Return true only if a page is part of reserved memory for crash dump kernel,
308 * but does not hold any data of loaded kernel image.
310 * Note that all the pages in crash dump kernel memory have been initially
311 * marked as Reserved in kexec_reserve_crashkres_pages().
313 * In hibernation, the pages which are Reserved and yet "nosave" are excluded
314 * from the hibernation iamge. crash_is_nosave() does thich check for crash
315 * dump kernel and will reduce the total size of hibernation image.
318 bool crash_is_nosave(unsigned long pfn)
326 /* in reserved memory? */
327 addr = __pfn_to_phys(pfn);
328 if ((addr < crashk_res.start) || (crashk_res.end < addr))
331 if (!kexec_crash_image)
334 /* not part of loaded kernel image? */
335 for (i = 0; i < kexec_crash_image->nr_segments; i++)
336 if (addr >= kexec_crash_image->segment[i].mem &&
337 addr < (kexec_crash_image->segment[i].mem +
338 kexec_crash_image->segment[i].memsz))
344 void crash_free_reserved_phys_range(unsigned long begin, unsigned long end)
349 for (addr = begin; addr < end; addr += PAGE_SIZE) {
350 page = phys_to_page(addr);
351 ClearPageReserved(page);
352 free_reserved_page(page);
355 #endif /* CONFIG_HIBERNATION */
357 void arch_crash_save_vmcoreinfo(void)
359 VMCOREINFO_NUMBER(VA_BITS);
360 /* Please note VMCOREINFO_NUMBER() uses "%d", not "%x" */
361 vmcoreinfo_append_str("NUMBER(kimage_voffset)=0x%llx\n",
363 vmcoreinfo_append_str("NUMBER(PHYS_OFFSET)=0x%llx\n",