summaryrefslogtreecommitdiff
path: root/drivers/base/firmware_loader/builtin/main.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2021-11-04 08:32:38 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2021-11-04 08:32:38 -0700
commit95faf6ba654dd334617f347023e65b06d791c4a6 (patch)
treed2b6b8dbb5bf3566ed696e0fb918e4ee2589f171 /drivers/base/firmware_loader/builtin/main.c
parent5c904c66ed4e86c31ac7c033b64274cebed04e0e (diff)
parent27e0bcd02990f7291adb0f111e300f06c495d509 (diff)
downloadlinux-95faf6ba654dd334617f347023e65b06d791c4a6.tar.gz
linux-95faf6ba654dd334617f347023e65b06d791c4a6.tar.bz2
linux-95faf6ba654dd334617f347023e65b06d791c4a6.zip
Merge tag 'driver-core-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH: "Here is the big set of driver core changes for 5.16-rc1. All of these have been in linux-next for a while now with no reported problems. Included in here are: - big update and cleanup of the sysfs abi documentation files and scripts from Mauro. We are almost at the place where we can properly check that the running kernel's sysfs abi is documented fully. - firmware loader updates - dyndbg updates - kernfs cleanups and fixes from Christoph - device property updates - component fix - other minor driver core cleanups and fixes" * tag 'driver-core-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (122 commits) device property: Drop redundant NULL checks x86/build: Tuck away built-in firmware under FW_LOADER vmlinux.lds.h: wrap built-in firmware support under FW_LOADER firmware_loader: move struct builtin_fw to the only place used x86/microcode: Use the firmware_loader built-in API firmware_loader: remove old DECLARE_BUILTIN_FIRMWARE() firmware_loader: formalize built-in firmware API component: do not leave master devres group open after bind dyndbg: refine verbosity 1-4 summary-detail gpiolib: acpi: Replace custom code with device_match_acpi_handle() i2c: acpi: Replace custom function with device_match_acpi_handle() driver core: Provide device_match_acpi_handle() helper dyndbg: fix spurious vNpr_info change dyndbg: no vpr-info on empty queries dyndbg: vpr-info on remove-module complete, not starting device property: Add missed header in fwnode.h Documentation: dyndbg: Improve cli param examples dyndbg: Remove support for ddebug_query param dyndbg: make dyndbg a known cli param dyndbg: show module in vpr-info in dd-exec-queries ...
Diffstat (limited to 'drivers/base/firmware_loader/builtin/main.c')
-rw-r--r--drivers/base/firmware_loader/builtin/main.c106
1 files changed, 106 insertions, 0 deletions
diff --git a/drivers/base/firmware_loader/builtin/main.c b/drivers/base/firmware_loader/builtin/main.c
new file mode 100644
index 000000000000..a065c3150897
--- /dev/null
+++ b/drivers/base/firmware_loader/builtin/main.c
@@ -0,0 +1,106 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Builtin firmware support */
+
+#include <linux/firmware.h>
+#include "../firmware.h"
+
+/* Only if FW_LOADER=y */
+#ifdef CONFIG_FW_LOADER
+
+struct builtin_fw {
+ char *name;
+ void *data;
+ unsigned long size;
+};
+
+extern struct builtin_fw __start_builtin_fw[];
+extern struct builtin_fw __end_builtin_fw[];
+
+static bool fw_copy_to_prealloc_buf(struct firmware *fw,
+ void *buf, size_t size)
+{
+ if (!buf)
+ return true;
+ if (size < fw->size)
+ return false;
+ memcpy(buf, fw->data, fw->size);
+ return true;
+}
+
+/**
+ * firmware_request_builtin() - load builtin firmware
+ * @fw: pointer to firmware struct
+ * @name: name of firmware file
+ *
+ * Some use cases in the kernel have a requirement so that no memory allocator
+ * is involved as these calls take place early in boot process. An example is
+ * the x86 CPU microcode loader. In these cases all the caller wants is to see
+ * if the firmware was built-in and if so use it right away. This can be used
+ * for such cases.
+ *
+ * This looks for the firmware in the built-in kernel. Only if the kernel was
+ * built-in with the firmware you are looking for will this return successfully.
+ *
+ * Callers of this API do not need to use release_firmware() as the pointer to
+ * the firmware is expected to be provided locally on the stack of the caller.
+ **/
+bool firmware_request_builtin(struct firmware *fw, const char *name)
+{
+ struct builtin_fw *b_fw;
+
+ if (!fw)
+ return false;
+
+ for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++) {
+ if (strcmp(name, b_fw->name) == 0) {
+ fw->size = b_fw->size;
+ fw->data = b_fw->data;
+ return true;
+ }
+ }
+
+ return false;
+}
+EXPORT_SYMBOL_NS_GPL(firmware_request_builtin, TEST_FIRMWARE);
+
+/**
+ * firmware_request_builtin_buf() - load builtin firmware into optional buffer
+ * @fw: pointer to firmware struct
+ * @name: name of firmware file
+ * @buf: If set this lets you use a pre-allocated buffer so that the built-in
+ * firmware into is copied into. This field can be NULL. It is used by
+ * callers such as request_firmware_into_buf() and
+ * request_partial_firmware_into_buf()
+ * @size: if buf was provided, the max size of the allocated buffer available.
+ * If the built-in firmware does not fit into the pre-allocated @buf this
+ * call will fail.
+ *
+ * This looks for the firmware in the built-in kernel. Only if the kernel was
+ * built-in with the firmware you are looking for will this call possibly
+ * succeed. If you passed a @buf the firmware will be copied into it *iff* the
+ * built-in firmware fits into the pre-allocated buffer size specified in
+ * @size.
+ *
+ * This caller is to be used internally by the firmware_loader only.
+ **/
+bool firmware_request_builtin_buf(struct firmware *fw, const char *name,
+ void *buf, size_t size)
+{
+ if (!firmware_request_builtin(fw, name))
+ return false;
+
+ return fw_copy_to_prealloc_buf(fw, buf, size);
+}
+
+bool firmware_is_builtin(const struct firmware *fw)
+{
+ struct builtin_fw *b_fw;
+
+ for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++)
+ if (fw->data == b_fw->data)
+ return true;
+
+ return false;
+}
+
+#endif