penguin: guest register access, CPUArchState CFFI headers, powerpc64el target

Dockerfile

@@ -26,6 +26,10 @@ RUN apt-get update && \
         zlib1g-dev && \
     rm -rf /var/lib/apt/lists/*
 
+# penguin-env-cffi-gen.py parses the built libraries' DWARF (needs recent
+# pyelftools for DWARF5) and verifies generated layouts with cffi.
+RUN pip3 install --no-cache-dir "pyelftools>=0.31" cffi
+
 COPY --exclude=.git \
      --exclude=.github \
      --exclude=build-system \

build.sh

@@ -32,7 +32,7 @@ COMMON_CONFIGURE_ARGS=(
     --disable-linux-aio
 )
 
-PENGUIN_SYSTEM_ARCHES="${PENGUIN_SYSTEM_ARCHES:-armel,aarch64,mipsel,mipseb,mips64el,mips64eb,powerpc,powerpc64,powerpc64le,riscv64,loongarch64,intel64}"
+PENGUIN_SYSTEM_ARCHES="${PENGUIN_SYSTEM_ARCHES:-armel,aarch64,mipsel,mipseb,mips64el,mips64eb,powerpc,powerpc64,powerpc64el,powerpc64le,riscv64,loongarch64,intel64}"
 
 configure_build_dir() {
     local build_dir="$1"
@@ -87,7 +87,7 @@ penguin_system_arch_to_qemu_target() {
         powerpc|ppc)
             printf "ppc-softmmu\n"
             ;;
-        powerpc64|powerpc64le|ppc64)
+        powerpc64|powerpc64le|powerpc64el|ppc64)
             printf "ppc64-softmmu\n"
             ;;
         riscv64)
@@ -180,6 +180,9 @@ python3 scripts/penguin-cffi-gen.py \
     --mode system \
     --build-dir build-system \
     --arches "$PENGUIN_SYSTEM_ARCHES"
+python3 scripts/penguin-env-cffi-gen.py \
+    --build-dir build-system \
+    --manifest build-system/qemu_cffi_system_manifest.json
 
 if [ -n "${PENGUIN_KVM_TARGETS:-}" ]; then
     kvm_targets="$PENGUIN_KVM_TARGETS"
@@ -209,6 +212,9 @@ if [ -n "$kvm_targets" ]; then
         --mode kvm \
         --build-dir build-kvm \
         --targets "$kvm_targets"
+    python3 scripts/penguin-env-cffi-gen.py \
+        --build-dir build-kvm \
+        --manifest build-kvm/qemu_cffi_kvm_manifest.json
 fi
 
 python3 scripts/penguin-qemu-package.py --output penguin-qemu.tar.gz

include/system/penguin.h

@@ -46,4 +46,25 @@ int penguin_qemu_add_mmio_region(uint64_t base, uint64_t size,
                                  penguin_mmio_write_cb_t write_cb,
                                  void *opaque);
 
+/*
+ * Guest register access by GDB core-feature register number. Reads append
+ * the register bytes (target byte order) into @buf and return the register
+ * width; writes consume exactly the register width from @buf. Both return
+ * a negative value on failure.
+ */
+int penguin_read_guest_reg(CPUState *cs, int regnum, uint8_t *buf,
+                           int buf_len);
+int penguin_write_guest_reg(CPUState *cs, int regnum, const uint8_t *buf,
+                            int len);
+
+/*
+ * Direct CPUArchState access. penguin_cpu_env returns the env pointer for
+ * a CPU (the layout contract validated in cpu-target.c); callers decode it
+ * with the build-generated CPUArchState CFFI header. penguin_sync_cpu_state
+ * must be called before env reads (and to make env writes stick) under
+ * hardware accelerators; it is a no-op under TCG.
+ */
+void *penguin_cpu_env(CPUState *cs);
+void penguin_sync_cpu_state(CPUState *cs);
+
 #endif /* QEMU_SYSTEM_PENGUIN_H */

scripts/penguin-cffi-gen.py

@@ -24,6 +24,7 @@
     "ppc": "ppc-softmmu",
     "powerpc64": "ppc64-softmmu",
     "powerpc64le": "ppc64-softmmu",
+    "powerpc64el": "ppc64-softmmu",
     "ppc64": "ppc64-softmmu",
     "riscv64": "riscv64-softmmu",
     "loongarch64": "loongarch64-softmmu",
@@ -118,6 +119,12 @@
                                  penguin_mmio_read_cb_t read_cb,
                                  penguin_mmio_write_cb_t write_cb,
                                  void *opaque);
+int penguin_read_guest_reg(CPUState *cs, int regnum, uint8_t *buf,
+                           int buf_len);
+int penguin_write_guest_reg(CPUState *cs, int regnum, const uint8_t *buf,
+                            int len);
+void *penguin_cpu_env(CPUState *cs);
+void penguin_sync_cpu_state(CPUState *cs);
 """