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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/firmware/google/coreboot_table.c
parentInitial commit. (diff)
downloadlinux-upstream.tar.xz
linux-upstream.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/firmware/google/coreboot_table.c')
-rw-r--r--drivers/firmware/google/coreboot_table.c230
1 files changed, 230 insertions, 0 deletions
diff --git a/drivers/firmware/google/coreboot_table.c b/drivers/firmware/google/coreboot_table.c
new file mode 100644
index 000000000..f3694d347
--- /dev/null
+++ b/drivers/firmware/google/coreboot_table.c
@@ -0,0 +1,230 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * coreboot_table.c
+ *
+ * Module providing coreboot table access.
+ *
+ * Copyright 2017 Google Inc.
+ * Copyright 2017 Samuel Holland <samuel@sholland.org>
+ */
+
+#include <linux/acpi.h>
+#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/of.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#include "coreboot_table.h"
+
+#define CB_DEV(d) container_of(d, struct coreboot_device, dev)
+#define CB_DRV(d) container_of(d, struct coreboot_driver, drv)
+
+static int coreboot_bus_match(struct device *dev, struct device_driver *drv)
+{
+ struct coreboot_device *device = CB_DEV(dev);
+ struct coreboot_driver *driver = CB_DRV(drv);
+
+ 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 void coreboot_bus_remove(struct device *dev)
+{
+ struct coreboot_device *device = CB_DEV(dev);
+ struct coreboot_driver *driver = CB_DRV(dev->driver);
+
+ if (driver->remove)
+ driver->remove(device);
+}
+
+static struct bus_type coreboot_bus_type = {
+ .name = "coreboot",
+ .match = coreboot_bus_match,
+ .probe = coreboot_bus_probe,
+ .remove = coreboot_bus_remove,
+};
+
+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);
+
+static int coreboot_table_populate(struct device *dev, void *ptr)
+{
+ int i, ret;
+ void *ptr_entry;
+ struct coreboot_device *device;
+ struct coreboot_table_entry *entry;
+ struct coreboot_table_header *header = ptr;
+
+ ptr_entry = ptr + header->header_bytes;
+ for (i = 0; i < header->table_entries; i++) {
+ entry = ptr_entry;
+
+ if (entry->size < sizeof(*entry)) {
+ dev_warn(dev, "coreboot table entry too small!\n");
+ return -EINVAL;
+ }
+
+ device = kzalloc(sizeof(device->dev) + entry->size, GFP_KERNEL);
+ if (!device)
+ return -ENOMEM;
+
+ 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(device->raw, ptr_entry, entry->size);
+
+ ret = device_register(&device->dev);
+ if (ret) {
+ put_device(&device->dev);
+ return ret;
+ }
+
+ ptr_entry += entry->size;
+ }
+
+ return 0;
+}
+
+static int coreboot_table_probe(struct platform_device *pdev)
+{
+ resource_size_t len;
+ struct coreboot_table_header *header;
+ struct resource *res;
+ struct device *dev = &pdev->dev;
+ void *ptr;
+ int ret;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res)
+ return -EINVAL;
+
+ len = resource_size(res);
+ if (!res->start || !len)
+ return -EINVAL;
+
+ /* Check just the header first to make sure things are sane */
+ header = memremap(res->start, sizeof(*header), MEMREMAP_WB);
+ if (!header)
+ return -ENOMEM;
+
+ len = header->header_bytes + header->table_bytes;
+ ret = strncmp(header->signature, "LBIO", sizeof(header->signature));
+ memunmap(header);
+ if (ret) {
+ dev_warn(dev, "coreboot table missing or corrupt!\n");
+ return -ENODEV;
+ }
+
+ ptr = memremap(res->start, len, MEMREMAP_WB);
+ if (!ptr)
+ return -ENOMEM;
+
+ ret = coreboot_table_populate(dev, ptr);
+
+ memunmap(ptr);
+
+ return ret;
+}
+
+static int __cb_dev_unregister(struct device *dev, void *dummy)
+{
+ device_unregister(dev);
+ return 0;
+}
+
+static int coreboot_table_remove(struct platform_device *pdev)
+{
+ bus_for_each_dev(&coreboot_bus_type, NULL, NULL, __cb_dev_unregister);
+ return 0;
+}
+
+#ifdef CONFIG_ACPI
+static const struct acpi_device_id cros_coreboot_acpi_match[] = {
+ { "GOOGCB00", 0 },
+ { "BOOT0000", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(acpi, cros_coreboot_acpi_match);
+#endif
+
+#ifdef CONFIG_OF
+static const struct of_device_id coreboot_of_match[] = {
+ { .compatible = "coreboot" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, coreboot_of_match);
+#endif
+
+static struct platform_driver coreboot_table_driver = {
+ .probe = coreboot_table_probe,
+ .remove = coreboot_table_remove,
+ .driver = {
+ .name = "coreboot_table",
+ .acpi_match_table = ACPI_PTR(cros_coreboot_acpi_match),
+ .of_match_table = of_match_ptr(coreboot_of_match),
+ },
+};
+
+static int __init coreboot_table_driver_init(void)
+{
+ int ret;
+
+ ret = bus_register(&coreboot_bus_type);
+ if (ret)
+ return ret;
+
+ ret = platform_driver_register(&coreboot_table_driver);
+ if (ret) {
+ bus_unregister(&coreboot_bus_type);
+ return ret;
+ }
+
+ return 0;
+}
+
+static void __exit coreboot_table_driver_exit(void)
+{
+ platform_driver_unregister(&coreboot_table_driver);
+ bus_unregister(&coreboot_bus_type);
+}
+
+module_init(coreboot_table_driver_init);
+module_exit(coreboot_table_driver_exit);
+
+MODULE_AUTHOR("Google, Inc.");
+MODULE_LICENSE("GPL");