1 files changed, 138 insertions, 0 deletions
diff --git a/drivers/platform/chrome/chromeos_pstore.c b/drivers/platform/chrome/chromeos_pstore.c
new file mode 100644
index 0000000000..f37c0ef4af
--- /dev/null
+++ b/drivers/platform/chrome/chromeos_pstore.c
@@ -0,0 +1,138 @@
+// SPDX-License-Identifier: GPL-2.0
+// Driver to instantiate Chromebook ramoops device.
+//
+// Copyright (C) 2013 Google, Inc.
+
+#include <linux/acpi.h>
+#include <linux/dmi.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pstore_ram.h>
+
+static const struct dmi_system_id chromeos_pstore_dmi_table[] __initconst = {
+	{
+		/*
+		 * Today all Chromebooks/boxes ship with Google_* as version and
+		 * coreboot as bios vendor. No other systems with this
+		 * combination are known to date.
+		 */
+		.matches = {
+			DMI_MATCH(DMI_BIOS_VENDOR, "coreboot"),
+			DMI_MATCH(DMI_BIOS_VERSION, "Google_"),
+		},
+	},
+	{
+		/* x86-alex, the first Samsung Chromebook. */
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
+			DMI_MATCH(DMI_PRODUCT_NAME, "Alex"),
+		},
+	},
+	{
+		/* x86-mario, the Cr-48 pilot device from Google. */
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "IEC"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "Mario"),
+		},
+	},
+	{
+		/* x86-zgb, the first Acer Chromebook. */
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "ACER"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "ZGB"),
+		},
+	},
+	{ }
+};
+MODULE_DEVICE_TABLE(dmi, chromeos_pstore_dmi_table);
+
+/*
+ * On x86 chromebooks/boxes, the firmware will keep the legacy VGA memory
+ * range untouched across reboots, so we use that to store our pstore
+ * contents for panic logs, etc.
+ */
+static struct ramoops_platform_data chromeos_ramoops_data = {
+	.mem_size	= 0x100000,
+	.mem_address	= 0xf00000,
+	.record_size	= 0x40000,
+	.console_size	= 0x20000,
+	.ftrace_size	= 0x20000,
+	.pmsg_size	= 0x20000,
+	.max_reason	= KMSG_DUMP_OOPS,
+};
+
+static struct platform_device chromeos_ramoops = {
+	.name = "ramoops",
+	.dev = {
+		.platform_data = &chromeos_ramoops_data,
+	},
+};
+
+#ifdef CONFIG_ACPI
+static const struct acpi_device_id cros_ramoops_acpi_match[] = {
+	{ "GOOG9999", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(acpi, cros_ramoops_acpi_match);
+
+static struct platform_driver chromeos_ramoops_acpi = {
+	.driver		= {
+		.name	= "chromeos_pstore",
+		.acpi_match_table = ACPI_PTR(cros_ramoops_acpi_match),
+	},
+};
+
+static int __init chromeos_probe_acpi(struct platform_device *pdev)
+{
+	struct resource *res;
+	resource_size_t len;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res)
+		return -ENOMEM;
+
+	len = resource_size(res);
+	if (!res->start || !len)
+		return -ENOMEM;
+
+	pr_info("chromeos ramoops using acpi device.\n");
+
+	chromeos_ramoops_data.mem_size = len;
+	chromeos_ramoops_data.mem_address = res->start;
+
+	return 0;
+}
+
+static bool __init chromeos_check_acpi(void)
+{
+	if (!platform_driver_probe(&chromeos_ramoops_acpi, chromeos_probe_acpi))
+		return true;
+	return false;
+}
+#else
+static inline bool chromeos_check_acpi(void) { return false; }
+#endif
+
+static int __init chromeos_pstore_init(void)
+{
+	bool acpi_dev_found;
+
+	/* First check ACPI for non-hardcoded values from firmware. */
+	acpi_dev_found = chromeos_check_acpi();
+
+	if (acpi_dev_found || dmi_check_system(chromeos_pstore_dmi_table))
+		return platform_device_register(&chromeos_ramoops);
+
+	return -ENODEV;
+}
+
+static void __exit chromeos_pstore_exit(void)
+{
+	platform_device_unregister(&chromeos_ramoops);
+}
+
+module_init(chromeos_pstore_init);
+module_exit(chromeos_pstore_exit);
+
+MODULE_DESCRIPTION("ChromeOS pstore module");
+MODULE_LICENSE("GPL v2");