ramdump: add ramdump support for kernel [4/6]

PD#165764: add ramdump support

1. Add Makefile and driver of ramdump;
2. Flush all cache before panic reboot;
3. Change panic reboot reason when ramdump is disabled;
4. Add dts support/open watch dog for chips.

Change-Id: Ieeb418f038bfda119c3156a7f8f8b05c8bc58ad2
Signed-off-by: tao zeng <tao.zeng@amlogic.com>

MAINTAINERS

@@ -13505,6 +13505,7 @@ F: drivers/amlogic/cpufreq/*
 AMLOGIC driver for memory extend
 M: Tao Zeng <tao.zeng@amlogic.com>
 F: drivers/amlogic/memory_ext/*
+F: include/linux/amlogic/ramdump.h
 
 AMLOGIC driver for memory extend
 M: Tao Zeng <tao.zeng@amlogic.com>

arch/arm64/boot/dts/amlogic/mesonaxg.dtsi

@@ -259,7 +259,7 @@
 
 	wdt_ee: watchdog@0xffd0f0d0 {
 		compatible = "amlogic, meson-wdt";
-		status = "disabled";
+		status = "okay";
 		default_timeout=<10>;
 		reset_watchdog_method=<1>; /* 0:sysfs,1:kernel */
 		reset_watchdog_time=<2>;
@@ -271,6 +271,11 @@
 		clocks = <&xtal>;
 	};
 
+	ram-dump {
+		compatible = "amlogic, ram_dump";
+		status = "okay";
+	};
+
 	pinctrl_aobus: pinctrl@ff800014{
 		compatible = "amlogic,meson-axg-aobus-pinctrl";
 		#address-cells = <2>;

arch/arm64/boot/dts/amlogic/mesong12a.dtsi

@@ -425,6 +425,11 @@
 		clocks = <&xtal>;
 	};
 
+	ram-dump {
+		compatible = "amlogic, ram_dump";
+		status = "okay";
+	};
+
 	jtag {
 		compatible = "amlogic, jtag";
 		status = "okay";
@@ -439,7 +444,6 @@
 				&gpio       GPIOC_5     0>;
 	};
 
-
 	saradc:saradc {
 		compatible = "amlogic,meson-g12a-saradc";
 		status = "okay";

arch/arm64/boot/dts/amlogic/mesongxl.dtsi

@@ -220,7 +220,7 @@
 
 	watchdog {
 		compatible = "amlogic, meson-wdt";
-		status = "disabled";
+		status = "okay";
 		default_timeout=<10>;
 		reset_watchdog_method=<1>; /* 0:sysfs,1:kernel */
 		reset_watchdog_time=<2>;
@@ -232,6 +232,11 @@
 		clocks = <&xtal>;
 	};
 
+	ram-dump {
+		compatible = "amlogic, ram_dump";
+		status = "okay";
+	};
+
 	jtag {
 		compatible = "amlogic, jtag";
 		status = "okay";

arch/arm64/boot/dts/amlogic/mesongxm.dtsi

@@ -243,7 +243,7 @@
 
 	watchdog {
 		compatible = "amlogic, meson-wdt";
-		status = "disabled";
+		status = "okay";
 		default_timeout=<10>;
 		reset_watchdog_method=<1>; /* 0:sysfs,1:kernel */
 		reset_watchdog_time=<2>;
@@ -255,6 +255,11 @@
 		clocks = <&xtal>;
 	};
 
+	ram-dump {
+		compatible = "amlogic, ram_dump";
+		status = "okay";
+	};
+
 	jtag {
 		compatible = "amlogic, jtag";
 		status = "disabled";

arch/arm64/boot/dts/amlogic/mesontxlx.dtsi

@@ -258,7 +258,7 @@
 
 	wdt_ee: watchdog@0xffd0f0d0 {
 		compatible = "amlogic, meson-wdt";
-		status = "disabled";
+		status = "watch";
 		default_timeout=<10>;
 		reset_watchdog_method=<1>; /* 0:sysfs,1:kernel */
 		reset_watchdog_time=<2>;
@@ -270,6 +270,11 @@
 		clocks = <&xtal>;
 	};
 
+	ram-dump {
+		compatible = "amlogic, ram_dump";
+		status = "okay";
+	};
+
 	amlogic-jtag {
 		compatible = "amlogic, jtag";
 		status = "okay";

arch/arm64/configs/meson64_defconfig

@@ -344,6 +344,7 @@ CONFIG_AMLOGIC_SARADC=y
 CONFIG_AMLOGIC_DDR_TOOL=y
 CONFIG_AMLOGIC_DDR_BANDWIDTH=y
 CONFIG_AMLOGIC_TEE=y
+CONFIG_AMLOGIC_RAMDUMP=y
 CONFIG_AMLOGIC_GPIO_IRQ=y
 CONFIG_AMLOGIC_ATV_DEMOD=y
 CONFIG_AMLOGIC_DEBUG=y

drivers/amlogic/memory_ext/Kconfig

@@ -19,6 +19,17 @@ config AMLOGIC_PAGE_TRACE
 		with allocate page count information of each caller functions from
 		/proc/pagetrace
 
+config AMLOGIC_RAMDUMP
+	bool "Amlogic RAM DUMP support"
+	depends on AMLOGIC_MEMORY_EXTEND
+	depends on PANIC_TIMEOUT != 0
+	default n
+	help
+		RAM dump support for amlogic platform, when system is rebooted
+		after panic/watch dog reboot, you may need this option to save
+		whole ram to /data/ partition. Which can be used for analyze
+		crash reason.
+
 config AMLOGIC_CMA
 	bool "Amlogic CMA change"
 	depends on AMLOGIC_MEMORY_EXTEND

drivers/amlogic/memory_ext/Makefile

@@ -2,3 +2,4 @@
 obj-$(CONFIG_AMLOGIC_PAGE_TRACE)  += page_trace.o
 obj-$(CONFIG_AMLOGIC_CMA)         += aml_cma.o
 obj-$(CONFIG_AMLOGIC_SLUB_DEBUG)  += aml_slub_debug.o
+obj-$(CONFIG_AMLOGIC_RAMDUMP)     += ram_dump.o

drivers/amlogic/memory_ext/ram_dump.c

@@ -0,0 +1,357 @@
+/*
+ * 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");

drivers/amlogic/reboot/reboot.c

@@ -33,6 +33,10 @@
 #include <asm/compiler.h>
 #include <linux/kdebug.h>
 #include <linux/arm-smccc.h>
+#ifdef CONFIG_AMLOGIC_RAMDUMP
+#include <linux/amlogic/ramdump.h>
+#define RAMDUMP_REPLACE_MSG	"ramdump disabled, replase panic to normal\n"
+#endif /* CONFIG_AMLOGIC_RAMDUMP */
 
 static u32 psci_function_id_restart;
 static u32 psci_function_id_poweroff;
@@ -59,8 +63,17 @@ static u32 parse_reason(const char *cmd)
 			reboot_reason = MESON_UBOOT_SUSPEND;
 	} else {
 		if (kernel_panic) {
-			if (strcmp(kernel_panic, "kernel_panic") == 0)
+			if (strcmp(kernel_panic, "kernel_panic") == 0) {
+			#ifdef CONFIG_AMLOGIC_RAMDUMP
+				if (ramdump_disabled()) {
+					reboot_reason = MESON_NORMAL_BOOT;
+					pr_info(RAMDUMP_REPLACE_MSG);
+				} else
+					reboot_reason = MESON_KERNEL_PANIC;
+			#else
 				reboot_reason = MESON_KERNEL_PANIC;
+			#endif
+			}
 		}
 
 	}

include/linux/amlogic/ramdump.h

@@ -0,0 +1,26 @@
+/*
+ * include/linux/amlogic/ramdump.h
+ *
+ * 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.
+ *
+ */
+
+#ifndef __RAMDUMP_H__
+#define __RAMDUMP_H__
+
+#define SET_REBOOT_REASON		0x82000049
+
+extern int ramdump_disabled(void);
+extern void ramdump_sync_data(void);
+
+#endif /* __RAMDUMP_H__ */

kernel/panic.c

@@ -25,6 +25,9 @@
 #include <linux/nmi.h>
 #include <linux/console.h>
 #include <linux/bug.h>
+#ifdef CONFIG_AMLOGIC_RAMDUMP
+#include <linux/amlogic/ramdump.h>
+#endif
 
 #define PANIC_TIMER_STEP 100
 #define PANIC_BLINK_SPD 18
@@ -179,6 +182,9 @@ void panic(const char *fmt, ...)
 		dump_stack();
 #endif
 
+#ifdef CONFIG_AMLOGIC_RAMDUMP
+	ramdump_sync_data();
+#endif
 	/*
 	 * If we have crashed and we have a crash kernel loaded let it handle
 	 * everything else.