platform/chrome: Add pstore platform_device

Add the ramoops pstore device so that we get logs of panics across reboots.

Signed-off-by: Olof Johansson <olof@lixom.net>

3 files changed, 116 insertions, 0 deletions

diff --git a/drivers/platform/chrome/Kconfig b/drivers/platform/chrome/Kconfig
index b13303e75a34..440ed776efd4 100644
--- a/drivers/platform/chrome/Kconfig
+++ b/drivers/platform/chrome/Kconfig
@@ -25,4 +25,18 @@ config CHROMEOS_LAPTOP
           If you have a supported Chromebook, choose Y or M here.
           The module will be called chromeos_laptop.
 
+config CHROMEOS_PSTORE
+        tristate "Chrome OS pstore support"
+        ---help---
+          This module instantiates the persistent storage on x86 ChromeOS
+          devices. It can be used to store away console logs and crash
+          information across reboots.
+
+          The range of memory used is 0xf00000-0x1000000, traditionally
+          the memory used to back VGA controller memory.
+
+          If you have a supported Chromebook, choose Y or M here.
+          The module will be called chromeos_pstore.
+
+
 endif # CHROMEOS_PLATFORMS
diff --git a/drivers/platform/chrome/Makefile b/drivers/platform/chrome/Makefile
index 015e9195e226..2b860ca7450f 100644
--- a/drivers/platform/chrome/Makefile
+++ b/drivers/platform/chrome/Makefile
@@ -1,2 +1,3 @@
 
 obj-$(CONFIG_CHROMEOS_LAPTOP)   += chromeos_laptop.o
+obj-$(CONFIG_CHROMEOS_PSTORE)   += chromeos_pstore.o
diff --git a/drivers/platform/chrome/chromeos_pstore.c b/drivers/platform/chrome/chromeos_pstore.c
new file mode 100644
index 000000000000..e0e0e65cf442
--- /dev/null
+++ b/drivers/platform/chrome/chromeos_pstore.c
@@ -0,0 +1,101 @@
+/*
+ *  chromeos_pstore.c - Driver to instantiate Chromebook ramoops device
+ *
+ *  Copyright (C) 2013 Google, Inc.
+ *
+ *  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, version 2 of the License.
+ */
+
+#include <linux/dmi.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pstore_ram.h>
+
+static struct dmi_system_id chromeos_pstore_dmi_table[] __initdata = {
+        {
+                /*
+                 * Today all Chromebooks/boxes ship with GOOGLE as vendor and
+                 * coreboot as bios vendor. No other systems with this
+                 * combination are known to date.
+                 */
+                .matches = {
+                        DMI_MATCH(DMI_SYS_VENDOR, "GOOGLE"),
+                        DMI_MATCH(DMI_BIOS_VENDOR, "coreboot"),
+                },
+        },
+        {
+                /*
+                 * The first Samsung Chromebox and Chromebook Series 5 550 use
+                 * coreboot but with Samsung as the system vendor.
+                 */
+                .matches = {
+                        DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG"),
+                        DMI_MATCH(DMI_BIOS_VENDOR, "coreboot"),
+                },
+        },
+        {
+                /* 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    = 0x20000,
+        .console_size   = 0x20000,
+        .ftrace_size    = 0x20000,
+        .dump_oops      = 1,
+};
+
+static struct platform_device chromeos_ramoops = {
+        .name = "ramoops",
+        .dev = {
+                .platform_data = &chromeos_ramoops_data,
+        },
+};
+
+static int __init chromeos_pstore_init(void)
+{
+        if (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("Chrome OS pstore module");
+MODULE_LICENSE("GPL");