--- /dev/null
+/*
+ * drivers/amlogic/memory_ext/ram_dump.c
+ *
+ * Copyright (C) 2017 Amlogic, Inc. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ */
+
+#include <linux/version.h>
+#include <linux/types.h>
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/mutex.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/reboot.h>
+#include <linux/memblock.h>
+#include <linux/amlogic/ramdump.h>
+#include <linux/amlogic/reboot.h>
+#include <linux/arm-smccc.h>
+#include <asm/cacheflush.h>
+
+static unsigned long ramdump_base __initdata;
+static unsigned long ramdump_size __initdata;
+static bool ramdump_disable __initdata;
+
+struct ramdump {
+ void __iomem *mem_base;
+ unsigned long mem_size;
+ struct mutex lock;
+ struct kobject *kobj;
+ struct work_struct clear_work;
+ int disable;
+};
+
+static struct ramdump *ram;
+
+static void meson_set_reboot_reason(int reboot_reason)
+{
+ struct arm_smccc_res smccc;
+
+ arm_smccc_smc(SET_REBOOT_REASON,
+ reboot_reason, 0, 0, 0, 0, 0, 0, &smccc);
+ return;
+}
+
+static int __init early_ramdump_para(char *buf)
+{
+ int ret;
+
+ if (!buf)
+ return -EINVAL;
+
+ pr_info("%s:%s\n", __func__, buf);
+ if (strcmp(buf, "disabled") == 0) {
+ ramdump_disable = 1;
+ } else {
+ ret = sscanf(buf, "%lx,%lx", &ramdump_base, &ramdump_size);
+ if (ret != 2) {
+ pr_err("invalid boot args\n");
+ ramdump_disable = 1;
+ }
+ pr_info("%s, base:%lx, size:%lx\n",
+ __func__, ramdump_base, ramdump_size);
+ ret = memblock_reserve(ramdump_base, PAGE_ALIGN(ramdump_size));
+ if (ret < 0) {
+ pr_info("reserve memblock %lx - %lx failed\n",
+ ramdump_base,
+ ramdump_base + PAGE_ALIGN(ramdump_size));
+ ramdump_disable = 1;
+ }
+ }
+ if (ramdump_disable)
+ meson_set_reboot_reason(MESON_NORMAL_BOOT);
+
+ return 0;
+}
+early_param("ramdump", early_ramdump_para);
+
+static ssize_t ramdump_bin_read(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *attr,
+ char *buf, loff_t off, size_t count)
+{
+ void *p = NULL;
+
+ if (!ram->mem_base || off >= ram->mem_size)
+ return 0;
+
+ if (off + count > ram->mem_size)
+ count = ram->mem_size - off;
+
+ p = ram->mem_base + off;
+ mutex_lock(&ram->lock);
+ memcpy(buf, p, count);
+ mutex_unlock(&ram->lock);
+
+ /* debug when read end */
+ if (off + count >= ram->mem_size)
+ pr_info("%s, p=%p %p, off:%lli, c:%zi\n",
+ __func__, buf, p, off, count);
+
+ return count;
+}
+
+int ramdump_disabled(void)
+{
+ if (ram)
+ return ram->disable;
+ return 0;
+}
+EXPORT_SYMBOL(ramdump_disabled);
+
+static ssize_t ramdump_bin_write(struct file *filp,
+ struct kobject *kobj,
+ struct bin_attribute *bin_attr,
+ char *buf, loff_t off, size_t count)
+{
+ if (ram->mem_base && !strncmp("reboot", buf, 6))
+ kernel_restart("RAM-DUMP finished\n");
+
+ if (!strncmp("disable", buf, 7)) {
+ ram->disable = 1;
+ meson_set_reboot_reason(MESON_NORMAL_BOOT);
+ }
+ if (!strncmp("enable", buf, 6)) {
+ ram->disable = 0;
+ meson_set_reboot_reason(MESON_KERNEL_PANIC);
+ }
+
+ return count;
+}
+
+static struct bin_attribute ramdump_attr = {
+ .attr = {
+ .name = "compmsg",
+ .mode = S_IRUGO | S_IWUSR,
+ },
+ .read = ramdump_bin_read,
+ .write = ramdump_bin_write,
+};
+
+/*
+ * clear memory to avoid large amount of memory not used.
+ * for ramdom data, it's hard to compress
+ */
+static void lazy_clear_work(struct work_struct *work)
+{
+ struct page *page;
+ struct list_head head, *pos, *next;
+ void *virt;
+ int order;
+ gfp_t flags = __GFP_NORETRY |
+ __GFP_NOWARN |
+ __GFP_MOVABLE;
+ unsigned long clear = 0, size = 0, free = 0, tick;
+
+ INIT_LIST_HEAD(&head);
+ order = MAX_ORDER - 1;
+ tick = sched_clock();
+ do {
+ page = alloc_pages(flags, order);
+ if (page) {
+ list_add(&page->lru, &head);
+ virt = page_address(page);
+ size = (1 << order) * PAGE_SIZE;
+ memset(virt, 0, size);
+ clear += size;
+ }
+ } while (page);
+ tick = sched_clock() - tick;
+
+ list_for_each_safe(pos, next, &head) {
+ page = list_entry(pos, struct page, lru);
+ list_del(&page->lru);
+ __free_pages(page, order);
+ free += size;
+ }
+ pr_info("clear:%lx, free:%lx, tick:%ld us\n",
+ clear, free, tick / 1000);
+}
+
+#ifdef CONFIG_ARM64
+void ramdump_sync_data(void)
+{
+ /*
+ * back port from old kernel verion for function
+ * flush_cache_all(), we need it for ram dump
+ */
+ asm volatile (
+ "mov x12, x30 \n"
+ "dsb sy \n"
+ "mrs x0, clidr_el1 \n"
+ "and x3, x0, #0x7000000 \n"
+ "lsr x3, x3, #23 \n"
+ "cbz x3, finished \n"
+ "mov x10, #0 \n"
+ "loop1: \n"
+ "add x2, x10, x10, lsr #1 \n"
+ "lsr x1, x0, x2 \n"
+ "and x1, x1, #7 \n"
+ "cmp x1, #2 \n"
+ "b.lt skip \n"
+ "mrs x9, daif \n"
+ "msr daifset, #2 \n"
+ "msr csselr_el1, x10 \n"
+ "isb \n"
+ "mrs x1, ccsidr_el1 \n"
+ "msr daif, x9 \n"
+ "and x2, x1, #7 \n"
+ "add x2, x2, #4 \n"
+ "mov x4, #0x3ff \n"
+ "and x4, x4, x1, lsr #3 \n"
+ "clz w5, w4 \n"
+ "mov x7, #0x7fff \n"
+ "and x7, x7, x1, lsr #13 \n"
+ "loop2: \n"
+ "mov x9, x4 \n"
+ "loop3: \n"
+ "lsl x6, x9, x5 \n"
+ "orr x11, x10, x6 \n"
+ "lsl x6, x7, x2 \n"
+ "orr x11, x11, x6 \n"
+ "dc cisw, x11 \n"
+ "subs x9, x9, #1 \n"
+ "b.ge loop3 \n"
+ "subs x7, x7, #1 \n"
+ "b.ge loop2 \n"
+ "skip: \n"
+ "add x10, x10, #2 \n"
+ "cmp x3, x10 \n"
+ "b.gt loop1 \n"
+ "finished: \n"
+ "mov x10, #0 \n"
+ "msr csselr_el1, x10 \n"
+ "dsb sy \n"
+ "isb \n"
+ "mov x0, #0 \n"
+ "ic ialluis \n"
+ "ret x12 \n"
+ );
+}
+#else
+void ramdump_sync_data(void)
+{
+ flush_cache_all();
+}
+#endif
+
+static int ramdump_probe(struct platform_device *pdev)
+{
+ void __iomem *p;
+
+ ram = kzalloc(sizeof(struct ramdump), GFP_KERNEL);
+ if (!ram)
+ return -ENOMEM;
+
+ if (ramdump_disable)
+ ram->disable = 1;
+
+ if (!ramdump_base || !ramdump_size) {
+ pr_info("NO valid ramdump args:%lx %lx\n",
+ ramdump_base, ramdump_size);
+ } else {
+ p = ioremap_cache(ramdump_base, ramdump_size);
+ ram->mem_base = p;
+ ram->mem_size = ramdump_size;
+ pr_info("%s, mem_base:%p, %lx, size:%lx\n",
+ __func__, p, ramdump_base, ramdump_size);
+ }
+ ram->kobj = kobject_create_and_add("mdump", kernel_kobj);
+ if (!ram->kobj) {
+ pr_err("%s, create sysfs failed\n", __func__);
+ goto err;
+ }
+ ramdump_attr.size = ram->mem_size;
+ if (sysfs_create_bin_file(ram->kobj, &ramdump_attr)) {
+ pr_err("%s, create sysfs1 failed\n", __func__);
+ goto err1;
+ }
+ mutex_init(&ram->lock);
+ if (!ram->disable && !ram->mem_size) {
+ INIT_WORK(&ram->clear_work, lazy_clear_work);
+ schedule_work(&ram->clear_work);
+ }
+ return 0;
+
+err1:
+ kobject_put(ram->kobj);
+err:
+ if (ram->mem_base)
+ iounmap(ram->mem_base);
+ kfree(ram);
+
+ return -EINVAL;
+}
+
+static int ramdump_remove(struct platform_device *pdev)
+{
+ sysfs_remove_bin_file(ram->kobj, &ramdump_attr);
+ iounmap(ram->mem_base);
+ kobject_put(ram->kobj);
+ kfree(ram);
+ return 0;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id ramdump_dt_match[] = {
+ {
+ .compatible = "amlogic, ram_dump",
+ },
+ {},
+};
+#endif
+
+static struct platform_driver ramdump_driver = {
+ .driver = {
+ .name = "mdump",
+ .owner = THIS_MODULE,
+ #ifdef CONFIG_OF
+ .of_match_table = ramdump_dt_match,
+ #endif
+ },
+ .probe = ramdump_probe,
+ .remove = ramdump_remove,
+};
+
+static int __init ramdump_init(void)
+{
+ int ret;
+
+ ret = platform_driver_register(&ramdump_driver);
+
+ return ret;
+}
+
+static void __exit ramdump_uninit(void)
+{
+ platform_driver_unregister(&ramdump_driver);
+}
+
+subsys_initcall(ramdump_init);
+module_exit(ramdump_uninit);
+MODULE_DESCRIPTION("AMLOGIC ramdump driver");
+MODULE_LICENSE("GPL");
projects / platform / kernel / linux-amlogic.git / commitdiff