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path: root/drivers/firmware/google/coreboot_table.c
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Diffstat (limited to 'drivers/firmware/google/coreboot_table.c')
-rw-r--r--drivers/firmware/google/coreboot_table.c130
1 files changed, 97 insertions, 33 deletions
diff --git a/drivers/firmware/google/coreboot_table.c b/drivers/firmware/google/coreboot_table.c
index 0019d3ec18dd4..19db5709ae288 100644
--- a/drivers/firmware/google/coreboot_table.c
+++ b/drivers/firmware/google/coreboot_table.c
@@ -4,6 +4,7 @@
* Module providing coreboot table access.
*
* Copyright 2017 Google Inc.
+ * Copyright 2017 Samuel Holland <samuel@sholland.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License v2.0 as published by
@@ -15,37 +16,96 @@
* GNU General Public License for more details.
*/
+#include <linux/device.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
+#include <linux/slab.h>
#include "coreboot_table.h"
-struct coreboot_table_entry {
- u32 tag;
- u32 size;
-};
+#define CB_DEV(d) container_of(d, struct coreboot_device, dev)
+#define CB_DRV(d) container_of(d, struct coreboot_driver, drv)
static struct coreboot_table_header __iomem *ptr_header;
-/*
- * This function parses the coreboot table for an entry that contains the base
- * address of the given entry tag. The coreboot table consists of a header
- * directly followed by a number of small, variable-sized entries, which each
- * contain an identifying tag and their length as the first two fields.
- */
-int coreboot_table_find(int tag, void *data, size_t data_size)
+static int coreboot_bus_match(struct device *dev, struct device_driver *drv)
{
- struct coreboot_table_header header;
- struct coreboot_table_entry entry;
- void *ptr_entry;
- int i;
+ struct coreboot_device *device = CB_DEV(dev);
+ struct coreboot_driver *driver = CB_DRV(drv);
- if (!ptr_header)
- return -EPROBE_DEFER;
+ return device->entry.tag == driver->tag;
+}
+static int coreboot_bus_probe(struct device *dev)
+{
+ int ret = -ENODEV;
+ struct coreboot_device *device = CB_DEV(dev);
+ struct coreboot_driver *driver = CB_DRV(dev->driver);
+
+ if (driver->probe)
+ ret = driver->probe(device);
+
+ return ret;
+}
+
+static int coreboot_bus_remove(struct device *dev)
+{
+ int ret = 0;
+ struct coreboot_device *device = CB_DEV(dev);
+ struct coreboot_driver *driver = CB_DRV(dev->driver);
+
+ if (driver->remove)
+ ret = driver->remove(device);
+
+ return ret;
+}
+
+static struct bus_type coreboot_bus_type = {
+ .name = "coreboot",
+ .match = coreboot_bus_match,
+ .probe = coreboot_bus_probe,
+ .remove = coreboot_bus_remove,
+};
+
+static int __init coreboot_bus_init(void)
+{
+ return bus_register(&coreboot_bus_type);
+}
+module_init(coreboot_bus_init);
+
+static void coreboot_device_release(struct device *dev)
+{
+ struct coreboot_device *device = CB_DEV(dev);
+
+ kfree(device);
+}
+
+int coreboot_driver_register(struct coreboot_driver *driver)
+{
+ driver->drv.bus = &coreboot_bus_type;
+
+ return driver_register(&driver->drv);
+}
+EXPORT_SYMBOL(coreboot_driver_register);
+
+void coreboot_driver_unregister(struct coreboot_driver *driver)
+{
+ driver_unregister(&driver->drv);
+}
+EXPORT_SYMBOL(coreboot_driver_unregister);
+
+int coreboot_table_init(struct device *dev, void __iomem *ptr)
+{
+ int i, ret;
+ void *ptr_entry;
+ struct coreboot_device *device;
+ struct coreboot_table_entry entry;
+ struct coreboot_table_header header;
+
+ ptr_header = ptr;
memcpy_fromio(&header, ptr_header, sizeof(header));
if (strncmp(header.signature, "LBIO", sizeof(header.signature))) {
@@ -54,37 +114,41 @@ int coreboot_table_find(int tag, void *data, size_t data_size)
}
ptr_entry = (void *)ptr_header + header.header_bytes;
-
for (i = 0; i < header.table_entries; i++) {
memcpy_fromio(&entry, ptr_entry, sizeof(entry));
- if (entry.tag == tag) {
- if (data_size < entry.size)
- return -EINVAL;
- memcpy_fromio(data, ptr_entry, entry.size);
+ device = kzalloc(sizeof(struct device) + entry.size, GFP_KERNEL);
+ if (!device) {
+ ret = -ENOMEM;
+ break;
+ }
+
+ dev_set_name(&device->dev, "coreboot%d", i);
+ device->dev.parent = dev;
+ device->dev.bus = &coreboot_bus_type;
+ device->dev.release = coreboot_device_release;
+ memcpy_fromio(&device->entry, ptr_entry, entry.size);
- return 0;
+ ret = device_register(&device->dev);
+ if (ret) {
+ put_device(&device->dev);
+ break;
}
ptr_entry += entry.size;
}
- return -ENOENT;
-}
-EXPORT_SYMBOL(coreboot_table_find);
-
-int coreboot_table_init(void __iomem *ptr)
-{
- ptr_header = ptr;
-
- return 0;
+ return ret;
}
EXPORT_SYMBOL(coreboot_table_init);
int coreboot_table_exit(void)
{
- if (ptr_header)
+ if (ptr_header) {
+ bus_unregister(&coreboot_bus_type);
iounmap(ptr_header);
+ ptr_header = NULL;
+ }
return 0;
}