mirror of
https://github.com/linuxboot/heads.git
synced 2024-12-22 14:22:26 +00:00
90 lines
2.7 KiB
Diff
90 lines
2.7 KiB
Diff
From 9090a0266eb13b823656216c665182d45a4cd19b Mon Sep 17 00:00:00 2001
|
|
From: Krystian Hebel <krystian.hebel@3mdeb.com>
|
|
Date: Tue, 28 Mar 2023 18:31:21 +0200
|
|
Subject: [PATCH] drivers/firmware/google: expose CBMEM as sysfs file
|
|
|
|
Signed-off-by: Krystian Hebel <krystian.hebel@3mdeb.com>
|
|
---
|
|
drivers/firmware/google/Kconfig | 8 ++++++
|
|
drivers/firmware/google/coreboot_table.c | 33 ++++++++++++++++++++++++
|
|
2 files changed, 41 insertions(+)
|
|
|
|
diff --git a/drivers/firmware/google/Kconfig b/drivers/firmware/google/Kconfig
|
|
index a3a6ca659ffa..2d18ee174043 100644
|
|
--- a/drivers/firmware/google/Kconfig
|
|
+++ b/drivers/firmware/google/Kconfig
|
|
@@ -29,6 +29,14 @@ config GOOGLE_COREBOOT_TABLE
|
|
device tree node /firmware/coreboot.
|
|
If unsure say N.
|
|
|
|
+config GOOGLE_COREBOOT_CBMEM
|
|
+ bool "Expose CBMEM as file"
|
|
+ depends on GOOGLE_COREBOOT_TABLE
|
|
+ help
|
|
+ This option exposes raw contents of coreboot's CBMEM to be consumed
|
|
+ by userspace tools. Path to file: /sys/firmware/cbmem.
|
|
+ If unsure say N.
|
|
+
|
|
config GOOGLE_COREBOOT_TABLE_ACPI
|
|
tristate
|
|
select GOOGLE_COREBOOT_TABLE
|
|
diff --git a/drivers/firmware/google/coreboot_table.c b/drivers/firmware/google/coreboot_table.c
|
|
index 8d132e4f008a..f93bdc49b1ac 100644
|
|
--- a/drivers/firmware/google/coreboot_table.c
|
|
+++ b/drivers/firmware/google/coreboot_table.c
|
|
@@ -84,6 +84,18 @@ void coreboot_driver_unregister(struct coreboot_driver *driver)
|
|
}
|
|
EXPORT_SYMBOL(coreboot_driver_unregister);
|
|
|
|
+#ifdef CONFIG_GOOGLE_COREBOOT_CBMEM
|
|
+static ssize_t cbmem_read(struct file *filp, struct kobject *kobp,
|
|
+ struct bin_attribute *bin_attr, char *buf,
|
|
+ loff_t pos, size_t count)
|
|
+{
|
|
+ return memory_read_from_buffer(buf, count, &pos,
|
|
+ bin_attr->private, bin_attr->size);
|
|
+}
|
|
+
|
|
+static BIN_ATTR_RO(cbmem, 0);
|
|
+#endif
|
|
+
|
|
static int coreboot_table_populate(struct device *dev, void *ptr)
|
|
{
|
|
int i, ret;
|
|
@@ -160,11 +172,32 @@ static int coreboot_table_probe(struct platform_device *pdev)
|
|
}
|
|
memunmap(ptr);
|
|
|
|
+#ifdef CONFIG_GOOGLE_COREBOOT_CBMEM
|
|
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
|
|
+ if (res && res->start && res->end && resource_size(res)) {
|
|
+ bin_attr_cbmem.size = resource_size(res);
|
|
+ bin_attr_cbmem.private = memremap(res->start,
|
|
+ resource_size(res),
|
|
+ MEMREMAP_WB);
|
|
+ if (sysfs_create_bin_file(firmware_kobj, &bin_attr_cbmem)) {
|
|
+ bin_attr_cbmem.size = 0;
|
|
+ bin_attr_cbmem.private = NULL;
|
|
+ }
|
|
+ }
|
|
+#endif
|
|
+
|
|
return ret;
|
|
}
|
|
|
|
static int coreboot_table_remove(struct platform_device *pdev)
|
|
{
|
|
+#ifdef CONFIG_GOOGLE_COREBOOT_CBMEM
|
|
+ if (bin_attr_cbmem.private) {
|
|
+ sysfs_remove_bin_file(firmware_kobj, &bin_attr_cbmem);
|
|
+ memunmap(bin_attr_cbmem.private);
|
|
+ }
|
|
+#endif
|
|
+
|
|
bus_unregister(&coreboot_bus_type);
|
|
return 0;
|
|
}
|
|
--
|
|
2.17.1
|
|
|