Luis Chamberlain 48d09e9787 firmware_loader: formalize built-in firmware API
Formalize the built-in firmware with a proper API. This can later
be used by other callers where all they need is built-in firmware.

We export the firmware_request_builtin() call for now only
under the TEST_FIRMWARE symbol namespace as there are no
direct modular users for it. If they pop up they are free
to export it generally. Built-in code always gets access to
the callers and we'll demonstrate a hidden user which has been
lurking in the kernel for a while and the reason why using a
proper API was better long term.

Reviewed-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Link: https://lore.kernel.org/r/20211021155843.1969401-2-mcgrof@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-22 14:13:44 +02:00

43 lines
1.6 KiB
Makefile

# SPDX-License-Identifier: GPL-2.0
obj-y += main.o
# Create $(fwdir) from $(CONFIG_EXTRA_FIRMWARE_DIR) -- if it doesn't have a
# leading /, it's relative to $(srctree).
fwdir := $(subst $(quote),,$(CONFIG_EXTRA_FIRMWARE_DIR))
fwdir := $(addprefix $(srctree)/,$(filter-out /%,$(fwdir)))$(filter /%,$(fwdir))
firmware := $(addsuffix .gen.o, $(subst $(quote),,$(CONFIG_EXTRA_FIRMWARE)))
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))