RISC-V Build Infrastructure

This adds RISC-V into the build system enabling the following targets:

- riscv32-softmmu
- riscv64-softmmu
- riscv32-linux-user
- riscv64-linux-user

This adds defaults configs for RISC-V, enables the build for the RISC-V
CPU core, hardware, and Linux User Emulation. The 'qemu-binfmt-conf.sh'
script is updated to add the RISC-V ELF magic.

Expected checkpatch errors for consistency reasons:

ERROR: line over 90 characters
FILE: scripts/qemu-binfmt-conf.sh

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Sagar Karandikar <sagark@eecs.berkeley.edu>
Signed-off-by: Michael Clark <mjc@sifive.com>

arch_init.c

@@ -71,6 +71,8 @@ int graphic_depth = 32;
 #define QEMU_ARCH QEMU_ARCH_OPENRISC
 #elif defined(TARGET_PPC)
 #define QEMU_ARCH QEMU_ARCH_PPC
+#elif defined(TARGET_RISCV)
+#define QEMU_ARCH QEMU_ARCH_RISCV
 #elif defined(TARGET_S390X)
 #define QEMU_ARCH QEMU_ARCH_S390X
 #elif defined(TARGET_SH4)

configure

@@ -6797,6 +6797,16 @@ case "$target_name" in
     echo "TARGET_ABI32=y" >> $config_target_mak
     gdb_xml_files="power64-core.xml power-fpu.xml power-altivec.xml power-spe.xml power-vsx.xml"
   ;;
+  riscv32)
+    TARGET_BASE_ARCH=riscv
+    TARGET_ABI_DIR=riscv
+    mttcg=yes
+  ;;
+  riscv64)
+    TARGET_BASE_ARCH=riscv
+    TARGET_ABI_DIR=riscv
+    mttcg=yes
+  ;;
   sh4|sh4eb)
     TARGET_ARCH=sh4
     bflt="yes"
@@ -6966,6 +6976,9 @@ for i in $ARCH $TARGET_BASE_ARCH ; do
   ppc*)
     disas_config "PPC"
   ;;
+  riscv)
+    disas_config "RISCV"
+  ;;
   s390*)
     disas_config "S390"
   ;;

cpus.c

@@ -2081,6 +2081,9 @@ CpuInfoList *qmp_query_cpus(Error **errp)
 #elif defined(TARGET_SPARC)
         SPARCCPU *sparc_cpu = SPARC_CPU(cpu);
         CPUSPARCState *env = &sparc_cpu->env;
+#elif defined(TARGET_RISCV)
+        RISCVCPU *riscv_cpu = RISCV_CPU(cpu);
+        CPURISCVState *env = &riscv_cpu->env;
 #elif defined(TARGET_MIPS)
         MIPSCPU *mips_cpu = MIPS_CPU(cpu);
         CPUMIPSState *env = &mips_cpu->env;
@@ -2120,6 +2123,9 @@ CpuInfoList *qmp_query_cpus(Error **errp)
 #elif defined(TARGET_S390X)
         info->value->arch = CPU_INFO_ARCH_S390;
         info->value->u.s390.cpu_state = env->cpu_state;
+#elif defined(TARGET_RISCV)
+        info->value->arch = CPU_INFO_ARCH_RISCV;
+        info->value->u.riscv.pc = env->pc;
 #else
         info->value->arch = CPU_INFO_ARCH_OTHER;
 #endif

default-configs/riscv32-linux-user.mak

@@ -0,0 +1 @@
+# Default configuration for riscv-linux-user

default-configs/riscv32-softmmu.mak

@@ -0,0 +1,4 @@
+# Default configuration for riscv-softmmu
+
+CONFIG_SERIAL=y
+CONFIG_VIRTIO=y

default-configs/riscv64-linux-user.mak

@@ -0,0 +1 @@
+# Default configuration for riscv-linux-user

default-configs/riscv64-softmmu.mak

@@ -0,0 +1,4 @@
+# Default configuration for riscv-softmmu
+
+CONFIG_SERIAL=y
+CONFIG_VIRTIO=y

hw/riscv/Makefile.objs

@@ -0,0 +1,11 @@
+obj-y += riscv_htif.o
+obj-y += riscv_hart.o
+obj-y += sifive_e.o
+obj-y += sifive_clint.o
+obj-y += sifive_prci.o
+obj-y += sifive_plic.o
+obj-y += sifive_test.o
+obj-y += sifive_u.o
+obj-y += sifive_uart.o
+obj-y += spike.o
+obj-y += virt.o

include/sysemu/arch_init.h

@@ -24,6 +24,7 @@ enum {
     QEMU_ARCH_TRICORE = (1 << 16),
     QEMU_ARCH_NIOS2 = (1 << 17),
     QEMU_ARCH_HPPA = (1 << 18),
+    QEMU_ARCH_RISCV = (1 << 19),
 };
 
 extern const uint32_t arch_type;

qapi/misc.json

@@ -320,10 +320,12 @@
 #
 # @s390: since 2.12
 #
+# @riscv: since 2.12
+#
 # Since: 2.6
 ##
 { 'enum': 'CpuInfoArch',
-  'data': ['x86', 'sparc', 'ppc', 'mips', 'tricore', 's390', 'other' ] }
+  'data': ['x86', 'sparc', 'ppc', 'mips', 'tricore', 's390', 'riscv', 'other' ] }
 
 ##
 # @CpuInfo:
@@ -363,6 +365,7 @@
             'mips': 'CpuInfoMIPS',
             'tricore': 'CpuInfoTricore',
             's390': 'CpuInfoS390',
+            'riscv': 'CpuInfoRISCV',
             'other': 'CpuInfoOther' } }
 
 ##
@@ -422,6 +425,17 @@
 ##
 { 'struct': 'CpuInfoTricore', 'data': { 'PC': 'int' } }
 
+##
+# @CpuInfoRISCV:
+#
+# Additional information about a virtual RISCV CPU
+#
+# @pc: the instruction pointer
+#
+# Since 2.12
+##
+{ 'struct': 'CpuInfoRISCV', 'data': { 'pc': 'int' } }
+
 ##
 # @CpuInfoOther:
 #
@@ -533,6 +547,7 @@
             'mips': 'CpuInfoOther',
             'tricore': 'CpuInfoOther',
             's390': 'CpuInfoS390',
+            'riscv': 'CpuInfoRISCV',
             'other': 'CpuInfoOther' } }
 
 ##

scripts/qemu-binfmt-conf.sh

@@ -4,7 +4,7 @@
 
 qemu_target_list="i386 i486 alpha arm armeb sparc32plus ppc ppc64 ppc64le m68k \
 mips mipsel mipsn32 mipsn32el mips64 mips64el \
-sh4 sh4eb s390x aarch64 aarch64_be hppa"
+sh4 sh4eb s390x aarch64 aarch64_be hppa riscv32 riscv64"
 
 i386_magic='\x7fELF\x01\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x03\x00'
 i386_mask='\xff\xff\xff\xff\xff\xfe\xfe\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff'
@@ -100,6 +100,14 @@ hppa_magic='\x7f\x45\x4c\x46\x01\x02\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00
 hppa_mask='\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff'
 hppa_family=hppa
 
+riscv32_magic='\x7fELF\x01\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\xf3\x00'
+riscv32_mask='\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff'
+riscv32_family=riscv
+
+riscv64_magic='\x7fELF\x02\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\xf3\x00'
+riscv64_mask='\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff'
+riscv64_family=riscv
+
 qemu_get_family() {
     cpu=${HOST_ARCH:-$(uname -m)}
     case "$cpu" in
@@ -124,6 +132,9 @@ qemu_get_family() {
     sparc*)
         echo "sparc"
         ;;
+    riscv*)
+        echo "riscv"
+        ;;
     *)
         echo "$cpu"
         ;;

target/riscv/Makefile.objs

@@ -0,0 +1 @@
+obj-y += translate.o op_helper.o helper.o cpu.o fpu_helper.o gdbstub.o pmp.o