Merge remote-tracking branch 'remotes/xtensa/tags/20180316-xtensa' into staging

target/xtensa linux-user support.

- small cleanup for xtensa registers dumping (-d cpu);
- add support for debugging linux-user process with xtensa-linux-gdb
  (as opposed to xtensa-elf-gdb), which can only access unprivileged
  registers;
- enable MTTCG for target/xtensa;
- cleanup in linux-user/mmap area making sure that it works correctly
  with limited 30-bit-wide user address space;
- import xtensa-specific definitions from the linux kernel,
  conditionalize user-only/softmmu-only code and add handlers for
  signals, exceptions, process/thread creation and core registers dumping.

# gpg: Signature made Fri 16 Mar 2018 16:46:19 GMT
# gpg:                using RSA key 51F9CC91F83FA044
# gpg: Good signature from "Max Filippov <filippov@cadence.com>"
# gpg:                 aka "Max Filippov <max.filippov@cogentembedded.com>"
# gpg:                 aka "Max Filippov <jcmvbkbc@gmail.com>"
# Primary key fingerprint: 2B67 854B 98E5 327D CDEB  17D8 51F9 CC91 F83F A044

* remotes/xtensa/tags/20180316-xtensa:
  MAINTAINERS: fix W: address for xtensa
  qemu-binfmt-conf.sh: add qemu-xtensa
  target/xtensa: add linux-user support
  linux-user: drop unused target_msync function
  linux-user: fix target_mprotect/target_munmap error return values
  linux-user: fix assertion in shmdt
  linux-user: fix mmap/munmap/mprotect/mremap/shmat
  target/xtensa: support MTTCG
  target/xtensa: use correct number of registers in gdbstub
  target/xtensa: mark register windows in the dump
  target/xtensa: dump correct physical registers

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

# Conflicts:
#	linux-user/syscall.c

1 files changed, 58 insertions, 0 deletions

diff --git a/linux-user/elfload.c b/linux-user/elfload.c
index 9d10a5f592..4563a3190b 100644
--- a/linux-user/elfload.c
+++ b/linux-user/elfload.c
@@ -1273,6 +1273,64 @@ static inline void init_thread(struct target_pt_regs *regs,
 
 #endif /* TARGET_HPPA */
 
+#ifdef TARGET_XTENSA
+
+#define ELF_START_MMAP 0x20000000
+
+#define ELF_CLASS       ELFCLASS32
+#define ELF_ARCH        EM_XTENSA
+
+static inline void init_thread(struct target_pt_regs *regs,
+                               struct image_info *infop)
+{
+    regs->windowbase = 0;
+    regs->windowstart = 1;
+    regs->areg[1] = infop->start_stack;
+    regs->pc = infop->entry;
+}
+
+/* See linux kernel: arch/xtensa/include/asm/elf.h.  */
+#define ELF_NREG 128
+typedef target_elf_greg_t target_elf_gregset_t[ELF_NREG];
+
+enum {
+    TARGET_REG_PC,
+    TARGET_REG_PS,
+    TARGET_REG_LBEG,
+    TARGET_REG_LEND,
+    TARGET_REG_LCOUNT,
+    TARGET_REG_SAR,
+    TARGET_REG_WINDOWSTART,
+    TARGET_REG_WINDOWBASE,
+    TARGET_REG_THREADPTR,
+    TARGET_REG_AR0 = 64,
+};
+
+static void elf_core_copy_regs(target_elf_gregset_t *regs,
+                               const CPUXtensaState *env)
+{
+    unsigned i;
+
+    (*regs)[TARGET_REG_PC] = tswapreg(env->pc);
+    (*regs)[TARGET_REG_PS] = tswapreg(env->sregs[PS] & ~PS_EXCM);
+    (*regs)[TARGET_REG_LBEG] = tswapreg(env->sregs[LBEG]);
+    (*regs)[TARGET_REG_LEND] = tswapreg(env->sregs[LEND]);
+    (*regs)[TARGET_REG_LCOUNT] = tswapreg(env->sregs[LCOUNT]);
+    (*regs)[TARGET_REG_SAR] = tswapreg(env->sregs[SAR]);
+    (*regs)[TARGET_REG_WINDOWSTART] = tswapreg(env->sregs[WINDOW_START]);
+    (*regs)[TARGET_REG_WINDOWBASE] = tswapreg(env->sregs[WINDOW_BASE]);
+    (*regs)[TARGET_REG_THREADPTR] = tswapreg(env->uregs[THREADPTR]);
+    xtensa_sync_phys_from_window((CPUXtensaState *)env);
+    for (i = 0; i < env->config->nareg; ++i) {
+        (*regs)[TARGET_REG_AR0 + i] = tswapreg(env->phys_regs[i]);
+    }
+}
+
+#define USE_ELF_CORE_DUMP
+#define ELF_EXEC_PAGESIZE       4096
+
+#endif /* TARGET_XTENSA */
+
 #ifndef ELF_PLATFORM
 #define ELF_PLATFORM (NULL)
 #endif