Move from riscv64-sifive-mee to riscv64-sifive-elf

I've added support to our ELF toolchain that replaces the various
features of the MEE toolchain we used to have in a cleaner way.  This
allows us to both ship a single toolchain binary as well as remove some
command line arguments that were required by the MEE toolchain.

This simplifies the MEE's build scripts, and should also simplify users
build scripts as well.

Signed-off-by: Palmer Dabbelt <[email protected]>

.gitignore

@@ -25,3 +25,4 @@
 *.mk
 /return_pass
 /return_fail
+*.specs

Makefile.am

@@ -8,20 +8,39 @@
 %.c: mee/machine/@[email protected]
 %.S: mee/machine/@[email protected]
 %.o: mee/machine/@[email protected]
+%.c: riscv__menv__mee.specs
+%.S: riscv__menv__mee.specs
+%.o: riscv__menv__mee.specs
+%.c: riscv__mmachine__@[email protected]
+%.S: riscv__mmachine__@[email protected]
+%.o: riscv__mmachine__@[email protected]
 
 # Every test depends on the generated linker script.
-$(check_PROGRAMS): mee-@[email protected]
+$(check_PROGRAMS): riscv__mmachine__@[email protected]
 
 # Every test depends on the freshly-compiled library.
-$(check_PROGRAMS): libmee-@[email protected]
+$(check_PROGRAMS): libriscv__mmachine__@[email protected]
 
 # Generates a linker script that's more reasonable that whatever GCC's default
 # is.
 ldsdir = $(libdir)
-lds_DATA = mee-@[email protected]
-mee-@[email protected]: @LDSCRIPT_GENERATOR@ @[email protected]
+lds_DATA = riscv__mmachine__@[email protected]
+riscv__mmachine__@[email protected]: @LDSCRIPT_GENERATOR@ @[email protected]
 	$< --dtb $(filter %.dtb,$^) --linker $@
 
+# Generates a SPEC file that sets a reasonable set of default options for this
+# build.
+specdir = $(libdir)
+spec_DATA =
+
+spec_DATA += riscv__mmachine__@[email protected]
+riscv__mmachine__@[email protected]: @SPECS_GENERATOR@ @[email protected]
+	$< --dtb $(filter %.dtb,$^) --specs $@ --prefix @prefix@ --machine @MACHINE_NAME@
+
+spec_DATA += riscv__menv__mee.specs
+riscv__menv__mee.specs: riscv__menv__mee.specs.in
+	cat $^ > $@
+
 # In order to generate code that's actually compatible with a machine we must
 # pass the march and mabi arguments to GCC that coorespond to the hardware.
 # This is handled by generating a makefile fragment, including it, and then
@@ -45,6 +64,7 @@ nobase_include_HEADERS = \
 	mee/compiler.h \
 	mee/clock.h \
 	mee/io.h \
+	mee/machine.h \
 	mee/shutdown.h \
 	mee/tty.h \
 	mee/uart.h
@@ -64,14 +84,12 @@ mee/machine/@[email protected]: @MEE_HEADER_GENERATOR@ @[email protected]
 # Everything in here is compiled into a single library, which contains all the
 # source files in the project.  It's named for one specific machine, which GCC
 # uses to select the target machine that this MEE implementation points at.
-lib_LIBRARIES = libmee-@[email protected]
+lib_LIBRARIES = libriscv__mmachine__@[email protected]
 
-libmee_@MACHINE_NAME@_a_CFLAGS  = -mmee-machine=@MACHINE_NAME@
-libmee_@MACHINE_NAME@_a_CFLAGS += -ffunction-sections -fdata-sections
-libmee_@MACHINE_NAME@_a_CFLAGS += -march=$(FRAMEWORK_BOARD_DTS_MARCH) -mabi=$(FRAMEWORK_BOARD_DTS_MABI)
-libmee_@MACHINE_NAME@_a_CCASFLAGS = $(libmee_@MACHINE_NAME@_a_CFLAGS) -DASSEMBLY
+libriscv__mmachine__@MACHINE_NAME@_a_CFLAGS  = -menv=mee -mmachine=@MACHINE_NAME@
+libriscv__mmachine__@MACHINE_NAME@_a_CCASFLAGS = -menv=mee -mmachine=@MACHINE_NAME@
 
-libmee_@MACHINE_NAME@_a_SOURCES = \
+libriscv__mmachine__@MACHINE_NAME@_a_SOURCES = \
 	src/drivers/fixed-clock.c \
 	src/drivers/sifive,fe310-g000,hfrosc.c \
 	src/drivers/sifive,fe310-g000,hfxosc.c \
@@ -92,37 +110,28 @@ check_PROGRAMS =
 # The simplest possible pair of tests: one that passes and one that fails
 check_PROGRAMS       += return_pass
 return_pass_SOURCES   = test/return_pass.c
-return_pass_CFLAGS    = -mmee-machine=@MACHINE_NAME@
-return_pass_CFLAGS   += -ffunction-sections -fdata-sections
-return_pass_CFLAGS   += -march=$(FRAMEWORK_BOARD_DTS_MARCH) -mabi=$(FRAMEWORK_BOARD_DTS_MABI)
+return_pass_CFLAGS    = -menv=mee -mmachine=@MACHINE_NAME@
 return_pass_LDFLAGS   = -L. -Wl,--gc-sections -Wl,-Map=return_pass.map
 
 check_PROGRAMS       += return_fail
 return_fail_SOURCES   = test/return_fail.c
-return_fail_CFLAGS    = -mmee-machine=@MACHINE_NAME@
-return_fail_CFLAGS   += -ffunction-sections -fdata-sections
-return_fail_CFLAGS   += -march=$(FRAMEWORK_BOARD_DTS_MARCH) -mabi=$(FRAMEWORK_BOARD_DTS_MABI)
+return_fail_CFLAGS    = -menv=mee -mmachine=@MACHINE_NAME@
 return_fail_LDFLAGS   = -L. -Wl,--gc-sections -Wl,-Map=return_fail.map
 
 # A simple "Hello, World!" program that directly uses the MEE interface to
 # print to the serial terminal.
 check_PROGRAMS       += hello
 hello_SOURCES         = test/hello.c
-hello_CFLAGS          = -mmee-machine=@MACHINE_NAME@
-hello_CFLAGS         += -ffunction-sections -fdata-sections
-hello_CFLAGS         += -march=$(FRAMEWORK_BOARD_DTS_MARCH) -mabi=$(FRAMEWORK_BOARD_DTS_MABI)
+hello_CFLAGS          = -menv=mee -mmachine=@MACHINE_NAME@
 hello_LDFLAGS         = -L. -Wl,--gc-sections -Wl,-Map=hello.map
 
 check_PROGRAMS       += pll_set_hz
 pll_set_hz_SOURCES    = test/pll_set_hz.c
-pll_set_hz_CFLAGS     = -mmee-machine=@MACHINE_NAME@
-pll_set_hz_CFLAGS    += -ffunction-sections -fdata-sections
-pll_set_hz_CFLAGS    += -march=$(FRAMEWORK_BOARD_DTS_MARCH) -mabi=$(FRAMEWORK_BOARD_DTS_MABI)
+pll_set_hz_CFLAGS     = -menv=mee -mmachine=@MACHINE_NAME@
 pll_set_hz_LDFLAGS    = -L. -Wl,--gc-sections -Wl,-Map=pll_set_hz.map
 
 # Extra clean targets
 clean-local:
 	-rm -rf @[email protected]
 	-rm -rf mee/machine/@[email protected] @[email protected] mee-@[email protected]
-	-rm -rf return_pass.map return_fail.map
-	-rm -rf hello.map
+	-rm -rf *.map *.specs

configure.ac

@@ -139,6 +139,24 @@ AS_IF([test "x$MAKEATTRIBUTES_GENERATOR" != "xno"],
     [AC_MSG_ERROR([Unable to find freedom-makeattributes-generator, either place it in PATH or try the --with-makeattributes-generator argument.])]
 )
 
+# Allows users to specify a path to freedom-mee_specs-generator, which
+# generates GCC spec files to control the compilation of MEE based targets.
+AC_ARG_WITH([mee_specs-generator],
+    [AS_HELP_STRING([--with-mee_specs-generator=PATH], [Use the given path to freedom-mee_specs-generator])],
+    [],
+    [with_mee_specs_generator=check]
+)
+
+AC_ARG_VAR(SPECS_GENERATOR, [The absolute path of the freedom-mee_specs-generator])
+AS_IF([test "x$with_mee_specs_generator" == "xcheck"],
+    [AC_PATH_PROG(SPECS_GENERATOR, freedom-mee_specs-generator, [no])],
+    [SPECS_GENERATOR=$with_mee_specs_generator]
+)
+AS_IF([test "x$SPECS_GENERATOR" != "xno"],
+    [AC_SUBST([SPECS_GENERATOR], "$SPECS_GENERATOR")],
+    [AC_MSG_ERROR([Unable to find freedom-mee_specs-generator, either place it in PATH or try the --with-mee_specs-generator argument.])]
+)
+
 # Generates the remainder of the build system.
 AC_CONFIG_FILES([Makefile])
 AC_OUTPUT

mee/machine.h

@@ -0,0 +1,8 @@
+/* SPDX-License-Identifier: Apache-2.0 */
+/* Copyright 2018 SiFive, Inc */
+
+#ifndef __MEE_MACHINE_HEADER
+#error "The toolchain must define __MEE_MACHINE_HEADER"
+#endif
+
+#include __MEE_MACHINE_HEADER

riscv__menv__mee.specs.in

@@ -0,0 +1 @@
+

src/tty.c

@@ -2,6 +2,7 @@
 /* SPDX-License-Identifier: Apache-2.0 */
 
 #include <mee/uart.h>
+#include <mee/machine.h>
 
 #if defined(__MEE_DT_STDOUT_UART_HANDLE)
 /* This implementation serves as a small shim that interfaces with the first

test/pll_set_hz.c

@@ -8,7 +8,7 @@
 #define PLL_MAX_OUT 320000000
 
 void main() {
-#ifdef __ME_DT_SIFIVE_FE310_G000_PLL_HANDLE
+#ifdef __MEE_DT_SIFIVE_FE310_G000_PLL_HANDLE
     struct mee_clock * pll = __ME_DT_SIFIVE_FE310_G000_PLL_HANDLE;
 
     printf("Test harness for FE310-G000 PLL Set Frequency\n\n");