From 49c7d2557d92993a1e09e50c961b9d4f7ab1091b Mon Sep 17 00:00:00 2001
From: Dick Olsson <hi@senzilla.io>
Date: Wed, 22 Jul 2020 08:49:12 +0200
Subject: [PATCH] mk: core: ta: Configurable Python interpreter

Build systems that manage multiple different python interpreters need
explicit control over which version of the interpreter to use.
This patch enables one to override the default interpreter with the path
to a specific one.

Signed-off-by: Dick Olsson <hi@senzilla.io>
Reviewed-by: Jens Wiklander <jens.wiklander@linaro.org>
Reviewed-by: Jerome Forissier <jerome@forissier.org>
---
 core/arch/arm/arm.mk         |  2 ++
 core/arch/arm/kernel/link.mk | 22 +++++++++++-----------
 core/sub.mk                  | 10 +++++-----
 mk/config.mk                 |  6 ++++++
 mk/lib.mk                    |  2 +-
 ta/arch/arm/link.mk          |  2 +-
 ta/arch/arm/link_shlib.mk    |  2 +-
 ta/ta.mk                     |  2 +-
 8 files changed, 28 insertions(+), 20 deletions(-)

diff --git a/core/arch/arm/arm.mk b/core/arch/arm/arm.mk
index 5c9f16ef..878035c5 100644
--- a/core/arch/arm/arm.mk
+++ b/core/arch/arm/arm.mk
@@ -245,6 +245,7 @@ ta-mk-file-export-add-ta_arm32 += CROSS_COMPILE32 ?= $$(CROSS_COMPILE)_nl_
 ta-mk-file-export-add-ta_arm32 += CROSS_COMPILE_ta_arm32 ?= $$(CROSS_COMPILE32)_nl_
 ta-mk-file-export-add-ta_arm32 += COMPILER ?= gcc_nl_
 ta-mk-file-export-add-ta_arm32 += COMPILER_ta_arm32 ?= $$(COMPILER)_nl_
+ta-mk-file-export-add-ta_arm32 += PYTHON3 ?= python3_nl_
 endif
 
 ifneq ($(filter ta_arm64,$(ta-targets)),)
@@ -275,6 +276,7 @@ ta-mk-file-export-add-ta_arm64 += CROSS_COMPILE64 ?= $$(CROSS_COMPILE)_nl_
 ta-mk-file-export-add-ta_arm64 += CROSS_COMPILE_ta_arm64 ?= $$(CROSS_COMPILE64)_nl_
 ta-mk-file-export-add-ta_arm64 += COMPILER ?= gcc_nl_
 ta-mk-file-export-add-ta_arm64 += COMPILER_ta_arm64 ?= $$(COMPILER)_nl_
+ta-mk-file-export-add-ta_arm64 += PYTHON3 ?= python3_nl_
 endif
 
 # Set cross compiler prefix for each TA target
diff --git a/core/arch/arm/kernel/link.mk b/core/arch/arm/kernel/link.mk
index 1b89b895..69375ad6 100644
--- a/core/arch/arm/kernel/link.mk
+++ b/core/arch/arm/kernel/link.mk
@@ -62,13 +62,13 @@ cleanfiles += $(link-out-dir)/text_unpaged.ld.S
 $(link-out-dir)/text_unpaged.ld.S: $(link-out-dir)/unpaged.o
 	@$(cmd-echo-silent) '  GEN     $@'
 	$(q)$(READELFcore) -S -W $< | \
-		./scripts/gen_ld_sects.py .text. > $@
+		$(PYTHON3) ./scripts/gen_ld_sects.py .text. > $@
 
 cleanfiles += $(link-out-dir)/rodata_unpaged.ld.S
 $(link-out-dir)/rodata_unpaged.ld.S: $(link-out-dir)/unpaged.o
 	@$(cmd-echo-silent) '  GEN     $@'
 	$(q)$(READELFcore) -S -W $< | \
-		./scripts/gen_ld_sects.py .rodata. > $@
+		$(PYTHON3) ./scripts/gen_ld_sects.py .rodata. > $@
 
 
 cleanfiles += $(link-out-dir)/init_entries.txt
@@ -92,12 +92,12 @@ cleanfiles += $(link-out-dir)/text_init.ld.S
 $(link-out-dir)/text_init.ld.S: $(link-out-dir)/init.o
 	@$(cmd-echo-silent) '  GEN     $@'
 	$(q)$(READELFcore) -S -W $< | \
-		./scripts/gen_ld_sects.py .text. > $@
+		$(PYTHON3) ./scripts/gen_ld_sects.py .text. > $@
 
 cleanfiles += $(link-out-dir)/rodata_init.ld.S
 $(link-out-dir)/rodata_init.ld.S: $(link-out-dir)/init.o
 	@$(cmd-echo-silent) '  GEN     $@'
-	$(q)$(READELFcore) -S -W $< | ./scripts/gen_ld_sects.py .rodata. > $@
+	$(q)$(READELFcore) -S -W $< | $(PYTHON3) ./scripts/gen_ld_sects.py .rodata. > $@
 
 -include $(link-script-dep)
 
@@ -176,39 +176,39 @@ cleanfiles += $(link-out-dir)/tee-pager.bin
 $(link-out-dir)/tee-pager.bin: $(link-out-dir)/tee.elf scripts/gen_tee_bin.py
 	@echo Warning: $@ is deprecated
 	@$(cmd-echo-silent) '  GEN     $@'
-	$(q)scripts/gen_tee_bin.py --input $< --out_tee_pager_bin $@
+	$(q)$(PYTHON3) scripts/gen_tee_bin.py --input $< --out_tee_pager_bin $@
 
 cleanfiles += $(link-out-dir)/tee-pageable.bin
 $(link-out-dir)/tee-pageable.bin: $(link-out-dir)/tee.elf scripts/gen_tee_bin.py
 	@echo Warning: $@ is deprecated
 	@$(cmd-echo-silent) '  GEN     $@'
-	$(q)scripts/gen_tee_bin.py --input $< --out_tee_pageable_bin $@
+	$(q)$(PYTHON3) scripts/gen_tee_bin.py --input $< --out_tee_pageable_bin $@
 
 all: $(link-out-dir)/tee.bin
 cleanfiles += $(link-out-dir)/tee.bin
 $(link-out-dir)/tee.bin: $(link-out-dir)/tee.elf scripts/gen_tee_bin.py
 	@$(cmd-echo-silent) '  GEN     $@'
-	$(q)scripts/gen_tee_bin.py --input $< --out_tee_bin $@
+	$(q)$(PYTHON3) scripts/gen_tee_bin.py --input $< --out_tee_bin $@
 
 all: $(link-out-dir)/tee-header_v2.bin
 cleanfiles += $(link-out-dir)/tee-header_v2.bin
 $(link-out-dir)/tee-header_v2.bin: $(link-out-dir)/tee.elf \
 				   scripts/gen_tee_bin.py
 	@$(cmd-echo-silent) '  GEN     $@'
-	$(q)scripts/gen_tee_bin.py --input $< --out_header_v2 $@
+	$(q)$(PYTHON3) scripts/gen_tee_bin.py --input $< --out_header_v2 $@
 
 all: $(link-out-dir)/tee-pager_v2.bin
 cleanfiles += $(link-out-dir)/tee-pager_v2.bin
 $(link-out-dir)/tee-pager_v2.bin: $(link-out-dir)/tee.elf scripts/gen_tee_bin.py
 	@$(cmd-echo-silent) '  GEN     $@'
-	$(q)scripts/gen_tee_bin.py --input $< --out_pager_v2 $@
+	$(q)$(PYTHON3) scripts/gen_tee_bin.py --input $< --out_pager_v2 $@
 
 all: $(link-out-dir)/tee-pageable_v2.bin
 cleanfiles += $(link-out-dir)/tee-pageable_v2.bin
 $(link-out-dir)/tee-pageable_v2.bin: $(link-out-dir)/tee.elf \
 				     scripts/gen_tee_bin.py
 	@$(cmd-echo-silent) '  GEN     $@'
-	$(q)scripts/gen_tee_bin.py --input $< --out_pageable_v2 $@
+	$(q)$(PYTHON3) scripts/gen_tee_bin.py --input $< --out_pageable_v2 $@
 
 all: $(link-out-dir)/tee.symb_sizes
 cleanfiles += $(link-out-dir)/tee.symb_sizes
@@ -222,5 +222,5 @@ mem_usage: $(link-out-dir)/tee.mem_usage
 
 $(link-out-dir)/tee.mem_usage: $(link-out-dir)/tee.elf
 	@$(cmd-echo-silent) '  GEN     $@'
-	$(q)./scripts/mem_usage.py $< > $@
+	$(q)$(PYTHON3) ./scripts/mem_usage.py $< > $@
 endif
diff --git a/core/sub.mk b/core/sub.mk
index 03cc6bc7..0959c9a9 100644
--- a/core/sub.mk
+++ b/core/sub.mk
@@ -9,13 +9,13 @@ ifeq ($(CFG_WITH_USER_TA),y)
 gensrcs-y += ta_pub_key
 produce-ta_pub_key = ta_pub_key.c
 depends-ta_pub_key = $(TA_SIGN_KEY) scripts/pem_to_pub_c.py
-recipe-ta_pub_key = scripts/pem_to_pub_c.py --prefix ta_pub_key \
+recipe-ta_pub_key = $(PYTHON3) scripts/pem_to_pub_c.py --prefix ta_pub_key \
 		--key $(TA_SIGN_KEY) --out $(sub-dir-out)/ta_pub_key.c
 
 gensrcs-y += ldelf
 produce-ldelf = ldelf_hex.c
 depends-ldelf = scripts/gen_ldelf_hex.py $(out-dir)/ldelf/ldelf.elf
-recipe-ldelf = scripts/gen_ldelf_hex.py --input $(out-dir)/ldelf/ldelf.elf \
+recipe-ldelf = $(PYTHON3) scripts/gen_ldelf_hex.py --input $(out-dir)/ldelf/ldelf.elf \
 			--output $(sub-dir-out)/ldelf_hex.c
 endif
 
@@ -25,7 +25,7 @@ early-ta-$1-uuid := $(firstword $(subst ., ,$(notdir $1)))
 gensrcs-y += early-ta-$1
 produce-early-ta-$1 = early_ta_$$(early-ta-$1-uuid).c
 depends-early-ta-$1 = $1 scripts/ta_bin_to_c.py
-recipe-early-ta-$1 = scripts/ta_bin_to_c.py --compress --ta $1 \
+recipe-early-ta-$1 = $(PYTHON3) scripts/ta_bin_to_c.py --compress --ta $1 \
 		--out $(sub-dir-out)/early_ta_$$(early-ta-$1-uuid).c
 endef
 $(foreach f, $(EARLY_TA_PATHS), $(eval $(call process_early_ta,$(f))))
@@ -40,7 +40,7 @@ core-embed-fdt-c = $(out-dir)/$(arch-dir)/dts/$(CFG_EMBED_DTB_SOURCE_FILE:.dts=.
 gensrcs-y += embedded_secure_dtb
 produce-embedded_secure_dtb = arch/$(ARCH)/dts/$(CFG_EMBED_DTB_SOURCE_FILE:.dts=.c)
 depends-embedded_secure_dtb = $(core-embed-fdt-dtb) scripts/bin_to_c.py
-recipe-embedded_secure_dtb = scripts/bin_to_c.py \
+recipe-embedded_secure_dtb = $(PYTHON3) scripts/bin_to_c.py \
 				--bin $(core-embed-fdt-dtb) \
 				--vname embedded_secure_dtb \
 				--out $(core-embed-fdt-c)
@@ -58,7 +58,7 @@ $(conf-mk-xz-base64): $(conf-mk-file)
 gensrcs-y += conf_str
 produce-conf_str = conf.mk.xz.base64.c
 depends-conf_str = $(conf-mk-xz-base64)
-recipe-conf_str = scripts/bin_to_c.py --text --bin $(conf-mk-xz-base64) \
+recipe-conf_str = $(PYTHON3) scripts/bin_to_c.py --text --bin $(conf-mk-xz-base64) \
 			--out $(sub-dir-out)/conf.mk.xz.base64.c \
 			--vname conf_str
 endif
diff --git a/mk/config.mk b/mk/config.mk
index 70732c4d..1fe65576 100644
--- a/mk/config.mk
+++ b/mk/config.mk
@@ -32,6 +32,12 @@ endif
 # Supported values: undefined, 1, 2 and 3. 3 gives more warnings.
 WARNS ?= 3
 
+# Path to the Python interpreter used by the build system.
+# This variable is set to the default python3 interpreter in the user's
+# path. But build environments that require more explicit control can
+# set the path to a specific interpreter through this variable.
+PYTHON3 ?= python3
+
 # Define DEBUG=1 to compile without optimization (forces -O0)
 # DEBUG=1
 
diff --git a/mk/lib.mk b/mk/lib.mk
index 6e890893..3bd422d6 100644
--- a/mk/lib.mk
+++ b/mk/lib.mk
@@ -72,7 +72,7 @@ $(lib-shlibstrippedfile): $(lib-shlibfile)
 
 $(lib-shlibtafile): $(lib-shlibstrippedfile) $(TA_SIGN_KEY)
 	@$(cmd-echo-silent) '  SIGN    $$@'
-	$$(q)$$(SIGN) --key $(TA_SIGN_KEY) --uuid $(libuuid) --in $$< --out $$@
+	$$(q)$$(PYTHON3) $$(SIGN) --key $(TA_SIGN_KEY) --uuid $(libuuid) --in $$< --out $$@
 
 $(lib-libuuidln): $(lib-shlibfile)
 	@$(cmd-echo-silent) '  LN      $$@'
diff --git a/ta/arch/arm/link.mk b/ta/arch/arm/link.mk
index db7d0b9a..b95c0cba 100644
--- a/ta/arch/arm/link.mk
+++ b/ta/arch/arm/link.mk
@@ -2,7 +2,7 @@ link-script$(sm) = $(ta-dev-kit-dir$(sm))/src/ta.ld.S
 link-script-pp$(sm) = $(link-out-dir$(sm))/ta.lds
 link-script-dep$(sm) = $(link-out-dir$(sm))/.ta.ld.d
 
-SIGN_ENC ?= $(ta-dev-kit-dir$(sm))/scripts/sign_encrypt.py
+SIGN_ENC ?= $(PYTHON3) $(ta-dev-kit-dir$(sm))/scripts/sign_encrypt.py
 TA_SIGN_KEY ?= $(ta-dev-kit-dir$(sm))/keys/default_ta.pem
 
 ifeq ($(CFG_ENCRYPT_TA),y)
diff --git a/ta/arch/arm/link_shlib.mk b/ta/arch/arm/link_shlib.mk
index ed81e59a..cc177ef0 100644
--- a/ta/arch/arm/link_shlib.mk
+++ b/ta/arch/arm/link_shlib.mk
@@ -47,5 +47,5 @@ $(link-out-dir)/$(shlibuuid).elf: $(link-out-dir)/$(shlibname).so
 $(link-out-dir)/$(shlibuuid).ta: $(link-out-dir)/$(shlibname).stripped.so \
 				$(TA_SIGN_KEY)
 	@$(cmd-echo-silent) '  SIGN    $@'
-	$(q)$(SIGN) --key $(TA_SIGN_KEY) --uuid $(shlibuuid) \
+	$(q)$(PYTHON3) $(SIGN) --key $(TA_SIGN_KEY) --uuid $(shlibuuid) \
 		--in $< --out $@
diff --git a/ta/ta.mk b/ta/ta.mk
index 918880f4..59ed87f7 100644
--- a/ta/ta.mk
+++ b/ta/ta.mk
@@ -67,7 +67,7 @@ $$(arm32-user-sysregs-out)/$$(arm32-user-sysregs-$(1)-h): \
 		$(1) scripts/arm32_sysreg.py
 	@$(cmd-echo-silent) '  GEN     $$@'
 	$(q)mkdir -p $$(dir $$@)
-	$(q)scripts/arm32_sysreg.py --guard __$$(arm32-user-sysregs-$(1)-h) \
+	$(q)$(PYTHON3) scripts/arm32_sysreg.py --guard __$$(arm32-user-sysregs-$(1)-h) \
 		< $$< > $$@
 
 endef #process-arm32-user-sysreg
-- 
2.20.1