[PATCH v2] powerpc/purgatory: Omit use of bin2c

[Masahiro Yamada <masahiroy@kernel.org>]

The .incbin assembler directive is much faster than bin2c + $(CC).

Do similar refactoring as in commit 4c0f032d4963 ("s390/purgatory:
Omit use of bin2c").

Please note the .quad directive matches to size_t in C (both 8 byte)
because the purgatory is compiled only for the 64-bit kernel.
(KEXEC_FILE depends on PPC64).

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Segher Boessenkool <segher@kernel.crashing.org>
---

Changes in v2:
  - Fix a typo (kexec_purgatroy_end -> kexec_purgatory_end)

 arch/powerpc/Kconfig                     |  1 -
 arch/powerpc/purgatory/.gitignore        |  1 -
 arch/powerpc/purgatory/Makefile          |  8 ++------
 arch/powerpc/purgatory/kexec-purgatory.S | 14 ++++++++++++++
 scripts/remove-stale-files               |  2 ++
 5 files changed, 18 insertions(+), 8 deletions(-)
 create mode 100644 arch/powerpc/purgatory/kexec-purgatory.S

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 7aa12e88c580..5050af5c1a23 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -551,7 +551,6 @@ config KEXEC_FILE
 	bool "kexec file based system call"
 	select KEXEC_CORE
 	select HAVE_IMA_KEXEC if IMA
-	select BUILD_BIN2C
 	select KEXEC_ELF
 	depends on PPC64
 	depends on CRYPTO=y
diff --git a/arch/powerpc/purgatory/.gitignore b/arch/powerpc/purgatory/.gitignore
index b8dc6ff34254..5e40575c1f2b 100644
--- a/arch/powerpc/purgatory/.gitignore
+++ b/arch/powerpc/purgatory/.gitignore
@@ -1,3 +1,2 @@
 # SPDX-License-Identifier: GPL-2.0-only
-kexec-purgatory.c
 purgatory.ro
diff --git a/arch/powerpc/purgatory/Makefile b/arch/powerpc/purgatory/Makefile
index 348f59581052..a81d155b89ae 100644
--- a/arch/powerpc/purgatory/Makefile
+++ b/arch/powerpc/purgatory/Makefile
@@ -2,17 +2,13 @@
 
 KASAN_SANITIZE := n
 
-targets += trampoline_$(BITS).o purgatory.ro kexec-purgatory.c
+targets += trampoline_$(BITS).o purgatory.ro
 
 LDFLAGS_purgatory.ro := -e purgatory_start -r --no-undefined
 
 $(obj)/purgatory.ro: $(obj)/trampoline_$(BITS).o FORCE
 		$(call if_changed,ld)
 
-quiet_cmd_bin2c = BIN2C   $@
-      cmd_bin2c = $(objtree)/scripts/bin2c kexec_purgatory < $< > $@
-
-$(obj)/kexec-purgatory.c: $(obj)/purgatory.ro FORCE
-	$(call if_changed,bin2c)
+$(obj)/kexec-purgatory.o: $(obj)/purgatory.ro
 
 obj-y	+= kexec-purgatory.o
diff --git a/arch/powerpc/purgatory/kexec-purgatory.S b/arch/powerpc/purgatory/kexec-purgatory.S
new file mode 100644
index 000000000000..f494fd5a0526
--- /dev/null
+++ b/arch/powerpc/purgatory/kexec-purgatory.S
@@ -0,0 +1,14 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+	.section .rodata, "a"
+
+	.align	8
+kexec_purgatory:
+	.globl	kexec_purgatory
+	.incbin	"arch/powerpc/purgatory/purgatory.ro"
+.Lkexec_purgatory_end:
+
+	.align	8
+kexec_purgatory_size:
+	.globl	kexec_purgatory_size
+	.quad	.Lkexec_purgatory_end - kexec_purgatory
diff --git a/scripts/remove-stale-files b/scripts/remove-stale-files
index 7adab4618035..5a7543469698 100755
--- a/scripts/remove-stale-files
+++ b/scripts/remove-stale-files
@@ -20,6 +20,8 @@ set -e
 # yard. Stale files stay in this file for a while (for some release cycles?),
 # then will be really dead and removed from the code base entirely.
 
+rm -f arch/powerpc/purgatory/kexec-purgatory.c
+
 # These were previously generated source files. When you are building the kernel
 # with O=, make sure to remove the stale files in the output tree. Otherwise,
 # the build system wrongly compiles the stale ones.
-- 
2.34.1