[PATCH v4 0/4] firmware_loader: built-in API and make x86 use it

[PATCH v4 0/4] firmware_loader: built-in API and make x86 use it

[Luis Chamberlain]

The only change on this v4 is to fix a kconfig dependency
(EXTRA_FIRMWARE != "") which I missed to address on the v3 series.

Luis Chamberlain (4):
  firmware_loader: rename EXTRA_FIRMWARE and EXTRA_FIRMWARE_DIR
  firmware_loader: move builtin build helper to shared library
  test_firmware: move a few test knobs out to its library
  test_firmware: add support for testing built-in firmware

 .../driver-api/firmware/built-in-fw.rst       |  6 +-
 Documentation/x86/microcode.rst               |  8 +--
 arch/x86/Kconfig                              |  4 +-
 drivers/base/firmware_loader/Kconfig          | 31 ++++++---
 drivers/base/firmware_loader/Makefile         |  1 +
 drivers/base/firmware_loader/builtin/Makefile | 41 ++---------
 .../base/firmware_loader/builtin/lib.Makefile | 32 +++++++++
 .../firmware_loader/test-builtin/.gitignore   |  3 +
 .../firmware_loader/test-builtin/Makefile     | 18 +++++
 drivers/staging/media/av7110/Kconfig          |  4 +-
 lib/Kconfig.debug                             | 33 +++++++++
 lib/test_firmware.c                           | 52 +++++++++++++-
 .../testing/selftests/firmware/fw_builtin.sh  | 69 +++++++++++++++++++
 .../selftests/firmware/fw_filesystem.sh       | 16 -----
 tools/testing/selftests/firmware/fw_lib.sh    | 24 +++++++
 .../selftests/firmware/fw_run_tests.sh        |  2 +
 16 files changed, 270 insertions(+), 74 deletions(-)
 create mode 100644 drivers/base/firmware_loader/builtin/lib.Makefile
 create mode 100644 drivers/base/firmware_loader/test-builtin/.gitignore
 create mode 100644 drivers/base/firmware_loader/test-builtin/Makefile
 create mode 100755 tools/testing/selftests/firmware/fw_builtin.sh

-- 
2.30.2

[PATCH v4 1/4] firmware_loader: rename EXTRA_FIRMWARE and EXTRA_FIRMWARE_DIR

[Luis Chamberlain]

Now that we've tied loose ends on the built-in firmware API,
rename the kconfig symbols for it to reflect more that they are
associated to the firmware_loader and to make it easier to
understand what they are for.

Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
---
 .../driver-api/firmware/built-in-fw.rst       |  6 ++--
 Documentation/x86/microcode.rst               |  8 ++---
 arch/x86/Kconfig                              |  4 +--
 drivers/base/firmware_loader/Kconfig          | 31 ++++++++++++-------
 drivers/base/firmware_loader/builtin/Makefile |  6 ++--
 drivers/staging/media/av7110/Kconfig          |  4 +--
 6 files changed, 34 insertions(+), 25 deletions(-)

diff --git a/Documentation/driver-api/firmware/built-in-fw.rst b/Documentation/driver-api/firmware/built-in-fw.rst
index bc1c961bace1..a9a0ab8c9512 100644
--- a/Documentation/driver-api/firmware/built-in-fw.rst
+++ b/Documentation/driver-api/firmware/built-in-fw.rst
@@ -8,11 +8,11 @@ the filesystem. Instead, firmware can be looked for inside the kernel
 directly. You can enable built-in firmware using the kernel configuration
 options:
 
-  * CONFIG_EXTRA_FIRMWARE
-  * CONFIG_EXTRA_FIRMWARE_DIR
+  * CONFIG_FW_LOADER_BUILTIN_FILES
+  * CONFIG_FW_LOADER_BUILTIN_DIR
 
 There are a few reasons why you might want to consider building your firmware
-into the kernel with CONFIG_EXTRA_FIRMWARE:
+into the kernel with CONFIG_FW_LOADER_BUILTIN_FILES:
 
 * Speed
 * Firmware is needed for accessing the boot device, and the user doesn't
diff --git a/Documentation/x86/microcode.rst b/Documentation/x86/microcode.rst
index a320d37982ed..6a5e36bd16bb 100644
--- a/Documentation/x86/microcode.rst
+++ b/Documentation/x86/microcode.rst
@@ -114,13 +114,13 @@ Builtin microcode
 =================
 
 The loader supports also loading of a builtin microcode supplied through
-the regular builtin firmware method CONFIG_EXTRA_FIRMWARE. Only 64-bit is
-currently supported.
+the regular builtin firmware method using CONFIG_FW_LOADER_BUILTIN_FILES.
+Only 64-bit is currently supported.
 
 Here's an example::
 
-  CONFIG_EXTRA_FIRMWARE="intel-ucode/06-3a-09 amd-ucode/microcode_amd_fam15h.bin"
-  CONFIG_EXTRA_FIRMWARE_DIR="/lib/firmware"
+  CONFIG_FW_LOADER_BUILTIN_FILES="intel-ucode/06-3a-09 amd-ucode/microcode_amd_fam15h.bin"
+  CONFIG_FW_LOADER_BUILTIN_DIR="/lib/firmware"
 
 This basically means, you have the following tree structure locally::
 
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index d9830e7e1060..149e4c2a0379 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -1305,8 +1305,8 @@ config MICROCODE
 	  initrd for microcode blobs.
 
 	  In addition, you can build the microcode into the kernel. For that you
-	  need to add the vendor-supplied microcode to the CONFIG_EXTRA_FIRMWARE
-	  config option.
+	  need to add the vendor-supplied microcode to the configuration option
+	  CONFIG_FW_LOADER_BUILTIN_FILES
 
 config MICROCODE_INTEL
 	bool "Intel microcode loading support"
diff --git a/drivers/base/firmware_loader/Kconfig b/drivers/base/firmware_loader/Kconfig
index 5b24f3959255..d56f4c1c7db4 100644
--- a/drivers/base/firmware_loader/Kconfig
+++ b/drivers/base/firmware_loader/Kconfig
@@ -22,14 +22,14 @@ config FW_LOADER
 	  You typically want this built-in (=y) but you can also enable this
 	  as a module, in which case the firmware_class module will be built.
 	  You also want to be sure to enable this built-in if you are going to
-	  enable built-in firmware (CONFIG_EXTRA_FIRMWARE).
+	  enable built-in firmware (CONFIG_FW_LOADER_BUILTIN_FILES).
 
 if FW_LOADER
 
 config FW_LOADER_PAGED_BUF
 	bool
 
-config EXTRA_FIRMWARE
+config FW_LOADER_BUILTIN_FILES
 	string "Build named firmware blobs into the kernel binary"
 	help
 	  Device drivers which require firmware can typically deal with
@@ -43,14 +43,21 @@ config EXTRA_FIRMWARE
 	  in boot and cannot rely on the firmware being placed in an initrd or
 	  initramfs.
 
-	  This option is a string and takes the (space-separated) names of the
+	  Support for built-in firmware is not supported if you are using
+	  the firmware loader as a module.
+
+	  This option is a string and takes the space-separated names of the
 	  firmware files -- the same names that appear in MODULE_FIRMWARE()
 	  and request_firmware() in the source. These files should exist under
-	  the directory specified by the EXTRA_FIRMWARE_DIR option, which is
+	  the directory specified by the FW_LOADER_BUILTIN_DIR option, which is
 	  /lib/firmware by default.
 
-	  For example, you might set CONFIG_EXTRA_FIRMWARE="usb8388.bin", copy
-	  the usb8388.bin file into /lib/firmware, and build the kernel. Then
+	  For example, you might have set:
+
+	  CONFIG_FW_LOADER_BUILTIN_FILES="usb8388.bin"
+
+	  After this you would copy the usb8388.bin file into directory
+	  specified by FW_LOADER_BUILTIN_DIR and build the kernel. Then
 	  any request_firmware("usb8388.bin") will be satisfied internally
 	  inside the kernel without ever looking at your filesystem at runtime.
 
@@ -60,13 +67,15 @@ config EXTRA_FIRMWARE
 	  image since it combines both GPL and non-GPL work. You should
 	  consult a lawyer of your own before distributing such an image.
 
-config EXTRA_FIRMWARE_DIR
-	string "Firmware blobs root directory"
-	depends on EXTRA_FIRMWARE != ""
+config FW_LOADER_BUILTIN_DIR
+	string "Directory with firmware to be built-in to the kernel"
+	depends on FW_LOADER_BUILTIN_FILES != ""
 	default "/lib/firmware"
 	help
-	  This option controls the directory in which the kernel build system
-	  looks for the firmware files listed in the EXTRA_FIRMWARE option.
+	  This option specifies the directory which the kernel build system
+	  will use to look for the firmware files which are going to be
+	  built into the kernel using the space-separated
+	  FW_LOADER_BUILTIN_FILES entries.
 
 config FW_LOADER_USER_HELPER
 	bool "Enable the firmware sysfs fallback mechanism"
diff --git a/drivers/base/firmware_loader/builtin/Makefile b/drivers/base/firmware_loader/builtin/Makefile
index eb4be452062a..7cdd0b5c7384 100644
--- a/drivers/base/firmware_loader/builtin/Makefile
+++ b/drivers/base/firmware_loader/builtin/Makefile
@@ -1,12 +1,12 @@
 # SPDX-License-Identifier: GPL-2.0
 obj-y  += main.o
 
-# Create $(fwdir) from $(CONFIG_EXTRA_FIRMWARE_DIR) -- if it doesn't have a
+# Create $(fwdir) from $(CONFIG_FW_LOADER_BUILTIN_DIR) -- if it doesn't have a
 # leading /, it's relative to $(srctree).
-fwdir := $(subst $(quote),,$(CONFIG_EXTRA_FIRMWARE_DIR))
+fwdir := $(subst $(quote),,$(CONFIG_FW_LOADER_BUILTIN_DIR))
 fwdir := $(addprefix $(srctree)/,$(filter-out /%,$(fwdir)))$(filter /%,$(fwdir))
 
-firmware  := $(addsuffix .gen.o, $(subst $(quote),,$(CONFIG_EXTRA_FIRMWARE)))
+firmware  := $(addsuffix .gen.o, $(subst $(quote),,$(CONFIG_FW_LOADER_BUILTIN_FILES)))
 obj-y += $(firmware)
 
 FWNAME    = $(patsubst $(obj)/%.gen.S,%,$@)
diff --git a/drivers/staging/media/av7110/Kconfig b/drivers/staging/media/av7110/Kconfig
index 9faf9d2d4001..87c7702f72f6 100644
--- a/drivers/staging/media/av7110/Kconfig
+++ b/drivers/staging/media/av7110/Kconfig
@@ -31,8 +31,8 @@ config DVB_AV7110
 	  or /lib/firmware (depending on configuration of firmware hotplug).
 
 	  Alternatively, you can download the file and use the kernel's
-	  EXTRA_FIRMWARE configuration option to build it into your
-	  kernel image by adding the filename to the EXTRA_FIRMWARE
+	  FW_LOADER_BUILTIN_FILES configuration option to build it into your
+	  kernel image by adding the filename to the FW_LOADER_BUILTIN_FILES
 	  configuration option string.
 
 	  Say Y if you own such a card and want to use it.
-- 
2.30.2

[PATCH v4 2/4] firmware_loader: move builtin build helper to shared library

[Luis Chamberlain]

If we wanted to use a different directory for building target
builtin firmware it is easier if we just have a shared library
Makefile, and each target directory can then just include it and
populate the respective needed variables. This reduces clutter,
makes things easier to read, and also most importantly allows
us to not have to try to magically adjust only one target
kconfig symbol for built-in firmware files. Trying to do this
can easily end up causing odd build issues if the user is not
careful.

As an example issue, if we are going to try to extend the
FW_LOADER_BUILTIN_FILES list and FW_LOADER_BUILTIN_DIR in case
of a new test firmware builtin support currently our only option
would be modify the defaults of each of these in case test firmware
builtin support was enabled. Defaults however won't augment a prior
setting, and so if FW_LOADER_BUILTIN_DIR="/lib/firmware" and you
and want this to be changed to something like
FW_LOADER_BUILTIN_DIR="drivers/base/firmware_loader/test-builtin"
the change will not take effect as a prior build already had it
set, and the build would fail. Trying to augment / append the
variables in the Makefile just makes this very difficult to
read.

Using a library let's us split up possible built-in targets so
that the user does not have to be involved. This will be used
in a subsequent patch which will add another user to this
built-in firmware library Makefile and demo how to use it outside
of the default FW_LOADER_BUILTIN_DIR and FW_LOADER_BUILTIN_FILES.

Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
---
 drivers/base/firmware_loader/builtin/Makefile | 34 ++-----------------
 .../base/firmware_loader/builtin/lib.Makefile | 32 +++++++++++++++++
 2 files changed, 34 insertions(+), 32 deletions(-)
 create mode 100644 drivers/base/firmware_loader/builtin/lib.Makefile

diff --git a/drivers/base/firmware_loader/builtin/Makefile b/drivers/base/firmware_loader/builtin/Makefile
index 7cdd0b5c7384..9b0dc193f6c7 100644
--- a/drivers/base/firmware_loader/builtin/Makefile
+++ b/drivers/base/firmware_loader/builtin/Makefile
@@ -1,4 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0
+include $(srctree)/drivers/base/firmware_loader/builtin/lib.Makefile
+
 obj-y  += main.o
 
 # Create $(fwdir) from $(CONFIG_FW_LOADER_BUILTIN_DIR) -- if it doesn't have a
@@ -8,35 +10,3 @@ fwdir := $(addprefix $(srctree)/,$(filter-out /%,$(fwdir)))$(filter /%,$(fwdir))
 
 firmware  := $(addsuffix .gen.o, $(subst $(quote),,$(CONFIG_FW_LOADER_BUILTIN_FILES)))
 obj-y += $(firmware)
-
-FWNAME    = $(patsubst $(obj)/%.gen.S,%,$@)
-FWSTR     = $(subst $(comma),_,$(subst /,_,$(subst .,_,$(subst -,_,$(FWNAME)))))
-ASM_WORD  = $(if $(CONFIG_64BIT),.quad,.long)
-ASM_ALIGN = $(if $(CONFIG_64BIT),3,2)
-PROGBITS  = $(if $(CONFIG_ARM),%,@)progbits
-
-filechk_fwbin = \
-	echo "/* Generated by $(src)/Makefile */"		;\
-	echo "    .section .rodata"				;\
-	echo "    .p2align 4"					;\
-	echo "_fw_$(FWSTR)_bin:"				;\
-	echo "    .incbin \"$(fwdir)/$(FWNAME)\""		;\
-	echo "_fw_end:"						;\
-	echo "    .section .rodata.str,\"aMS\",$(PROGBITS),1"	;\
-	echo "    .p2align $(ASM_ALIGN)"			;\
-	echo "_fw_$(FWSTR)_name:"				;\
-	echo "    .string \"$(FWNAME)\""			;\
-	echo "    .section .builtin_fw,\"a\",$(PROGBITS)"	;\
-	echo "    .p2align $(ASM_ALIGN)"			;\
-	echo "    $(ASM_WORD) _fw_$(FWSTR)_name"		;\
-	echo "    $(ASM_WORD) _fw_$(FWSTR)_bin"			;\
-	echo "    $(ASM_WORD) _fw_end - _fw_$(FWSTR)_bin"
-
-$(obj)/%.gen.S: FORCE
-	$(call filechk,fwbin)
-
-# The .o files depend on the binaries directly; the .S files don't.
-$(addprefix $(obj)/, $(firmware)): $(obj)/%.gen.o: $(fwdir)/%
-
-targets := $(patsubst $(obj)/%,%, \
-                                $(shell find $(obj) -name \*.gen.S 2>/dev/null))
diff --git a/drivers/base/firmware_loader/builtin/lib.Makefile b/drivers/base/firmware_loader/builtin/lib.Makefile
new file mode 100644
index 000000000000..e979a67acfa7
--- /dev/null
+++ b/drivers/base/firmware_loader/builtin/lib.Makefile
@@ -0,0 +1,32 @@
+# SPDX-License-Identifier: GPL-2.0
+FWNAME    = $(patsubst $(obj)/%.gen.S,%,$@)
+FWSTR     = $(subst $(comma),_,$(subst /,_,$(subst .,_,$(subst -,_,$(FWNAME)))))
+ASM_WORD  = $(if $(CONFIG_64BIT),.quad,.long)
+ASM_ALIGN = $(if $(CONFIG_64BIT),3,2)
+PROGBITS  = $(if $(CONFIG_ARM),%,@)progbits
+
+filechk_fwbin = \
+	echo "/* Generated by $(src)/Makefile */"		;\
+	echo "    .section .rodata"				;\
+	echo "    .p2align 4"					;\
+	echo "_fw_$(FWSTR)_bin:"				;\
+	echo "    .incbin \"$(fwdir)/$(FWNAME)\""		;\
+	echo "_fw_end:"						;\
+	echo "    .section .rodata.str,\"aMS\",$(PROGBITS),1"	;\
+	echo "    .p2align $(ASM_ALIGN)"			;\
+	echo "_fw_$(FWSTR)_name:"				;\
+	echo "    .string \"$(FWNAME)\""			;\
+	echo "    .section .builtin_fw,\"a\",$(PROGBITS)"	;\
+	echo "    .p2align $(ASM_ALIGN)"			;\
+	echo "    $(ASM_WORD) _fw_$(FWSTR)_name"		;\
+	echo "    $(ASM_WORD) _fw_$(FWSTR)_bin"			;\
+	echo "    $(ASM_WORD) _fw_end - _fw_$(FWSTR)_bin"
+
+$(obj)/%.gen.S: FORCE
+	$(call filechk,fwbin)
+
+# The .o files depend on the binaries directly; the .S files don't.
+$(addprefix $(obj)/, $(firmware)): $(obj)/%.gen.o: $(fwdir)/%
+
+targets := $(patsubst $(obj)/%,%, \
+                                $(shell find $(obj) -name \*.gen.S 2>/dev/null))
-- 
2.30.2

[PATCH v4 3/4] test_firmware: move a few test knobs out to its library

[Luis Chamberlain]

These will be used by other tests cases in other files so
move them to the library.

Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
---
 .../testing/selftests/firmware/fw_filesystem.sh | 16 ----------------
 tools/testing/selftests/firmware/fw_lib.sh      | 17 +++++++++++++++++
 2 files changed, 17 insertions(+), 16 deletions(-)

diff --git a/tools/testing/selftests/firmware/fw_filesystem.sh b/tools/testing/selftests/firmware/fw_filesystem.sh
index c2a2a100114b..7d763b303057 100755
--- a/tools/testing/selftests/firmware/fw_filesystem.sh
+++ b/tools/testing/selftests/firmware/fw_filesystem.sh
@@ -118,27 +118,11 @@ test_config_present()
 	fi
 }
 
-# Defaults :
-#
-# send_uevent: 1
-# sync_direct: 0
-# name: test-firmware.bin
-# num_requests: 4
-config_reset()
-{
-	echo 1 >  $DIR/reset
-}
-
 release_all_firmware()
 {
 	echo 1 >  $DIR/release_all_firmware
 }
 
-config_set_name()
-{
-	echo -n $1 >  $DIR/config_name
-}
-
 config_set_into_buf()
 {
 	echo 1 >  $DIR/config_into_buf
diff --git a/tools/testing/selftests/firmware/fw_lib.sh b/tools/testing/selftests/firmware/fw_lib.sh
index 5b8c0fedee76..31b71fe11dc5 100755
--- a/tools/testing/selftests/firmware/fw_lib.sh
+++ b/tools/testing/selftests/firmware/fw_lib.sh
@@ -221,3 +221,20 @@ kconfig_has()
 		fi
 	fi
 }
+
+# Defaults :
+#
+# send_uevent: 1
+# sync_direct: 0
+# name: test-firmware.bin
+# num_requests: 4
+config_reset()
+{
+	echo 1 >  $DIR/reset
+}
+
+
+config_set_name()
+{
+	echo -n $1 >  $DIR/config_name
+}
-- 
2.30.2

[PATCH v4 4/4] test_firmware: add support for testing built-in firmware

[Luis Chamberlain]

This adds some basic knobs to let us test built-in firmware
support. We test to ensure built-in firmware is indeed used,
and that it matches the contents we expect. Likewise we test
that a file that should not be built-in was not present.

For older kernels with older test_firmware drivers (yes some
folks do test selftests this way and we support it), the new
built-in test will simply bail out early.

Reviewed-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
---
 drivers/base/firmware_loader/Makefile         |  1 +
 drivers/base/firmware_loader/builtin/Makefile |  1 +
 .../firmware_loader/test-builtin/.gitignore   |  3 +
 .../firmware_loader/test-builtin/Makefile     | 18 +++++
 lib/Kconfig.debug                             | 33 +++++++++
 lib/test_firmware.c                           | 52 +++++++++++++-
 .../testing/selftests/firmware/fw_builtin.sh  | 69 +++++++++++++++++++
 tools/testing/selftests/firmware/fw_lib.sh    |  7 ++
 .../selftests/firmware/fw_run_tests.sh        |  2 +
 9 files changed, 185 insertions(+), 1 deletion(-)
 create mode 100644 drivers/base/firmware_loader/test-builtin/.gitignore
 create mode 100644 drivers/base/firmware_loader/test-builtin/Makefile
 create mode 100755 tools/testing/selftests/firmware/fw_builtin.sh

diff --git a/drivers/base/firmware_loader/Makefile b/drivers/base/firmware_loader/Makefile
index e87843408fe6..dbeba0fa315d 100644
--- a/drivers/base/firmware_loader/Makefile
+++ b/drivers/base/firmware_loader/Makefile
@@ -1,6 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0
 # Makefile for the Linux firmware loader
 
+obj-$(CONFIG_TEST_FIRMWARE_BUILTIN) += test-builtin/
 obj-$(CONFIG_FW_LOADER_USER_HELPER) += fallback_table.o
 obj-$(CONFIG_FW_LOADER)	+= firmware_class.o
 firmware_class-objs := main.o
diff --git a/drivers/base/firmware_loader/builtin/Makefile b/drivers/base/firmware_loader/builtin/Makefile
index 9b0dc193f6c7..baad7777974b 100644
--- a/drivers/base/firmware_loader/builtin/Makefile
+++ b/drivers/base/firmware_loader/builtin/Makefile
@@ -2,6 +2,7 @@
 include $(srctree)/drivers/base/firmware_loader/builtin/lib.Makefile
 
 obj-y  += main.o
+obj-$(CONFIG_TEST_BUILTIN_FIRMWARE)  += test-builtin-firmware.bin.gen.o
 
 # Create $(fwdir) from $(CONFIG_FW_LOADER_BUILTIN_DIR) -- if it doesn't have a
 # leading /, it's relative to $(srctree).
diff --git a/drivers/base/firmware_loader/test-builtin/.gitignore b/drivers/base/firmware_loader/test-builtin/.gitignore
new file mode 100644
index 000000000000..1d46553f50a0
--- /dev/null
+++ b/drivers/base/firmware_loader/test-builtin/.gitignore
@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: GPL-2.0
+*.gen.S
+*.bin
diff --git a/drivers/base/firmware_loader/test-builtin/Makefile b/drivers/base/firmware_loader/test-builtin/Makefile
new file mode 100644
index 000000000000..04204ad7ede1
--- /dev/null
+++ b/drivers/base/firmware_loader/test-builtin/Makefile
@@ -0,0 +1,18 @@
+# SPDX-License-Identifier: GPL-2.0
+include $(srctree)/drivers/base/firmware_loader/builtin/lib.Makefile
+
+extra-y := test-builtin-firmware.bin
+$(obj)/test-builtin-firmware.bin: FORCE
+	@$(kecho) "  GEN     $@"
+	@(set -e;			\
+	(				\
+		echo 'ABCD0123';	\
+	) > $@)
+
+# Create $(fwdir) from $(CONFIG_TEST_FIRMWARE_BUILTIN_DIR) -- if it doesn't
+# have a leading /, it's relative to $(srctree).
+fwdir := $(subst $(quote),,$(CONFIG_TEST_FIRMWARE_BUILTIN_DIR))
+fwdir := $(addprefix $(srctree)/,$(filter-out /%,$(fwdir)))$(filter /%,$(fwdir))
+
+firmware  := $(addsuffix .gen.o, $(subst $(quote),,$(CONFIG_TEST_FIRMWARE_BUILTIN_FILES)))
+obj-y += $(firmware)
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 2a9b6dcdac4f..91aea0aba2b1 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -2327,6 +2327,39 @@ config TEST_FIRMWARE
 
 	  If unsure, say N.
 
+config TEST_FIRMWARE_BUILTIN
+	bool "Allow building built-in test firmware"
+	depends on TEST_FIRMWARE
+	help
+	  If enabled, firmware will be built into to the kernel so that
+	  loading it with the test_firmware driver can be tested. Disabling
+	  this will just mean the test firmware scripts won't find any
+	  built-in firmware. Enabling this will make the kernel generate the
+	  file test-builtin-firmware.bin inside local directory
+	  drivers/base/firmware_loader/test-builtin. This file will then
+	  be available whenever the request firmware API is used.
+
+	  Enabling this functionlity essentially overrides the location where
+	  you specify to find built-in firmware, and so should only be enabled
+	  if you don't need to build firmware into your kernel for full
+	  funcionality.
+
+	  This should be disabled on production kernels as otherwise you'll
+	  end up with a test firmware stuck into your final kernel image and
+	  with default built-in firmware support.
+
+	  If unsure, say N.
+
+config TEST_FIRMWARE_BUILTIN_FILES
+	string
+	depends on TEST_FIRMWARE_BUILTIN
+	default "test-builtin-firmware.bin"
+
+config TEST_FIRMWARE_BUILTIN_DIR
+	string
+	depends on TEST_FIRMWARE_BUILTIN
+	default "drivers/base/firmware_loader/test-builtin"
+
 config TEST_SYSCTL
 	tristate "sysctl test driver"
 	depends on PROC_SYSCTL
diff --git a/lib/test_firmware.c b/lib/test_firmware.c
index 1bccd6cd5f48..134f8c78d2d4 100644
--- a/lib/test_firmware.c
+++ b/lib/test_firmware.c
@@ -34,6 +34,7 @@ MODULE_IMPORT_NS(TEST_FIRMWARE);
 
 static DEFINE_MUTEX(test_fw_mutex);
 static const struct firmware *test_firmware;
+static struct firmware builtin_test_firmware;
 
 struct test_batched_req {
 	u8 idx;
@@ -58,6 +59,10 @@ struct test_batched_req {
  * @sync_direct: when the sync trigger is used if this is true
  *	request_firmware_direct() will be used instead.
  * @send_uevent: whether or not to send a uevent for async requests
+ * @is_builtin: used only internally to determine if the firmware was found
+ *	to be built-in to the kernel using only the API call
+ *	firmware_request_builtin(). We treat this specially as we are
+ *	responsible for the firmware struct.
  * @num_requests: number of requests to try per test case. This is trigger
  *	specific.
  * @reqs: stores all requests information
@@ -99,6 +104,7 @@ struct test_config {
 	bool partial;
 	bool sync_direct;
 	bool send_uevent;
+	bool is_builtin;
 	u8 num_requests;
 	u8 read_fw_idx;
 
@@ -120,7 +126,11 @@ static ssize_t test_fw_misc_read(struct file *f, char __user *buf,
 	ssize_t rc = 0;
 
 	mutex_lock(&test_fw_mutex);
-	if (test_firmware)
+	if (test_fw_config->is_builtin)
+		rc = simple_read_from_buffer(buf, size, offset,
+					     builtin_test_firmware.data,
+					     builtin_test_firmware.size);
+	else if (test_firmware)
 		rc = simple_read_from_buffer(buf, size, offset,
 					     test_firmware->data,
 					     test_firmware->size);
@@ -194,6 +204,7 @@ static int __test_firmware_config_init(void)
 	test_fw_config->buf_size = TEST_FIRMWARE_BUF_SIZE;
 	test_fw_config->file_offset = 0;
 	test_fw_config->partial = false;
+	test_fw_config->is_builtin = false;
 	test_fw_config->sync_direct = false;
 	test_fw_config->req_firmware = request_firmware;
 	test_fw_config->test_result = 0;
@@ -1051,6 +1062,44 @@ static ssize_t read_firmware_show(struct device *dev,
 }
 static DEVICE_ATTR_RO(read_firmware);
 
+/*
+ * In order to test this, set CONFIG_FW_LOADER_BUILTIN_FILES to a firmware file
+ * which will be built into the kernel image. Then echo the name into the
+ * "trigger_request_builtin" sysfs file of this module.
+ */
+static ssize_t trigger_request_builtin_store(struct device *dev,
+					     struct device_attribute *attr,
+					     const char *buf, size_t count)
+{
+	int rc = -ENOENT;
+
+	if (!test_fw_config->name) {
+		pr_warn("unconfigured firmware settings\n");
+		return rc;
+	}
+
+	pr_info("loading builtin '%s'\n", test_fw_config->name);
+
+	mutex_lock(&test_fw_mutex);
+
+	if (firmware_request_builtin(&builtin_test_firmware,
+				     test_fw_config->name)) {
+		/* This let's us diff against the firmware */
+		test_fw_config->is_builtin = true;
+		pr_info("loaded: %zu\n", builtin_test_firmware.size);
+		rc = count;
+		goto out;
+	}
+
+	pr_info("load of '%s' failed\n", test_fw_config->name);
+
+out:
+	mutex_unlock(&test_fw_mutex);
+
+	return rc;
+}
+static DEVICE_ATTR_WO(trigger_request_builtin);
+
 #define TEST_FW_DEV_ATTR(name)          &dev_attr_##name.attr
 
 static struct attribute *test_dev_attrs[] = {
@@ -1082,6 +1131,7 @@ static struct attribute *test_dev_attrs[] = {
 	TEST_FW_DEV_ATTR(release_all_firmware),
 	TEST_FW_DEV_ATTR(test_result),
 	TEST_FW_DEV_ATTR(read_firmware),
+	TEST_FW_DEV_ATTR(trigger_request_builtin),
 	NULL,
 };
 
diff --git a/tools/testing/selftests/firmware/fw_builtin.sh b/tools/testing/selftests/firmware/fw_builtin.sh
new file mode 100755
index 000000000000..44e4198ed88f
--- /dev/null
+++ b/tools/testing/selftests/firmware/fw_builtin.sh
@@ -0,0 +1,69 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Test loading built-in firmware
+set -e
+
+TEST_REQS_FW_SYSFS_FALLBACK="no"
+TEST_REQS_FW_SET_CUSTOM_PATH="yes"
+TEST_DIR=$(dirname $0)
+source $TEST_DIR/fw_lib.sh
+
+check_mods
+check_setup
+verify_reqs
+setup_tmp_file
+
+trap "test_finish" EXIT
+
+if [ "$HAS_FW_LOADER_USER_HELPER" = "yes" ]; then
+	# Turn down the timeout so failures don't take so long.
+	echo 1 >/sys/class/firmware/timeout
+fi
+
+# built-in firmware support can be optional to test
+if [[ "$HAS_FW_LOADER_BUILTIN" != "yes" || "$HAS_TEST_FIRMWARE_BUILTIN" != "yes" ]]; then
+	exit $ksft_skip
+fi
+
+echo "Testing builtin firmware API ... "
+
+config_trigger_builtin()
+{
+	echo -n 1 > $DIR/trigger_request_builtin
+}
+
+test_builtin_firmware()
+{
+	echo -n "Testing firmware_request_builtin() ... "
+	config_reset
+	config_set_name $TEST_FIRMWARE_BUILTIN_FILENAME
+	config_trigger_builtin
+	echo OK
+	# Verify the contents are what we expect.
+	echo -n "Verifying file integrity ..."
+	if ! diff -q "$FW" /dev/test_firmware >/dev/null ; then
+		echo "$0: firmware loaded content differs" >&2
+		exit 1
+	else
+		echo "firmware content matches what we expect - OK"
+	fi
+}
+
+test_builtin_firmware_nofile()
+{
+	echo -n "Testing firmware_request_builtin() with fake file... "
+	config_reset
+	config_set_name fake-${TEST_FIRMWARE_BUILTIN_FILENAME}
+	if config_trigger_builtin 2> /dev/null; then
+		echo "$0: firmware shouldn't have loaded" >&2
+	fi
+	echo "OK"
+}
+
+test_builtin_firmware
+test_builtin_firmware_nofile
+
+# Ensure test_fw_config->is_builtin is set back to false
+# otherwise we won't be able to diff against the right target
+# firmware for other tests.
+config_reset
diff --git a/tools/testing/selftests/firmware/fw_lib.sh b/tools/testing/selftests/firmware/fw_lib.sh
index 31b71fe11dc5..bbae33d9f5ed 100755
--- a/tools/testing/selftests/firmware/fw_lib.sh
+++ b/tools/testing/selftests/firmware/fw_lib.sh
@@ -15,6 +15,10 @@ TEST_DIR=$(dirname $0)
 # To reproduce rename this to test-firmware.bin
 TEST_FIRMWARE_INTO_BUF_FILENAME=test-firmware-into-buf.bin
 
+# We should use a different filename for built-in firmware otherwise
+# we'd always have the file present.
+TEST_FIRMWARE_BUILTIN_FILENAME=test-builtin-firmware.bin
+
 # Kselftest framework requirement - SKIP code is 4.
 ksft_skip=4
 
@@ -63,6 +67,9 @@ check_setup()
 	HAS_FW_LOADER_USER_HELPER="$(kconfig_has CONFIG_FW_LOADER_USER_HELPER=y)"
 	HAS_FW_LOADER_USER_HELPER_FALLBACK="$(kconfig_has CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y)"
 	HAS_FW_LOADER_COMPRESS="$(kconfig_has CONFIG_FW_LOADER_COMPRESS=y)"
+	HAS_FW_LOADER_USER_HELPER="$(kconfig_has CONFIG_FW_LOADER_USER_HELPER=y)"
+	HAS_FW_LOADER_BUILTIN="$(kconfig_has CONFIG_FW_LOADER=y)"
+	HAS_TEST_FIRMWARE_BUILTIN="$(kconfig_has CONFIG_TEST_FIRMWARE_BUILTIN=y)"
 	PROC_FW_IGNORE_SYSFS_FALLBACK="0"
 	PROC_FW_FORCE_SYSFS_FALLBACK="0"
 
diff --git a/tools/testing/selftests/firmware/fw_run_tests.sh b/tools/testing/selftests/firmware/fw_run_tests.sh
index 777377078d5e..08a9bf043333 100755
--- a/tools/testing/selftests/firmware/fw_run_tests.sh
+++ b/tools/testing/selftests/firmware/fw_run_tests.sh
@@ -65,6 +65,8 @@ echo "Running namespace test: "
 $TEST_DIR/fw_namespace $DIR/trigger_request
 echo "OK"
 
+$TEST_DIR/fw_builtin.sh
+
 if [ -f $FW_FORCE_SYSFS_FALLBACK ]; then
 	run_test_config_0001
 	run_test_config_0002
-- 
2.30.2

Re: [PATCH v4 0/4] firmware_loader: built-in API and make x86 use it

[Luis Chamberlain]

On Mon, Oct 25, 2021 at 12:50:27PM -0700, Luis Chamberlain wrote:
> The only change on this v4 is to fix a kconfig dependency
> (EXTRA_FIRMWARE != "") which I missed to address on the v3 series.

Hey Greg, now that the merge window is closed let me know if you'd like
a resend of this or if you can take it as-is.

  Luis

Re: [PATCH v4 0/4] firmware_loader: built-in API and make x86 use it

[Greg KH]

On Tue, Nov 16, 2021 at 04:15:33PM -0800, Luis Chamberlain wrote:
> On Mon, Oct 25, 2021 at 12:50:27PM -0700, Luis Chamberlain wrote:
> > The only change on this v4 is to fix a kconfig dependency
> > (EXTRA_FIRMWARE != "") which I missed to address on the v3 series.
> 
> Hey Greg, now that the merge window is closed let me know if you'd like
> a resend of this or if you can take it as-is.

All now queued up, thanks.

greg k-h