Merge remote-tracking branch 'remotes/pmaydell/tags/pull-target-arm-20181008' into staging

target-arm queue:
 * target/arm: fix error in a code comment
 * virt: Suppress external aborts on virt-2.10 and earlier
 * target/arm: Correct condition for v8M callee stack push
 * target/arm: Don't read r4 from v8M exception stackframe twice
 * target/arm: Support SVE in system emulation mode
 * target/arm: Implement v8M hardware stack limit checking
 * hw/display/bcm2835_fb: Silence Coverity warning about multiply overflow

# gpg: Signature made Mon 08 Oct 2018 14:58:53 BST
# gpg:                using RSA key 3C2525ED14360CDE
# gpg: Good signature from "Peter Maydell <peter.maydell@linaro.org>"
# gpg:                 aka "Peter Maydell <pmaydell@gmail.com>"
# gpg:                 aka "Peter Maydell <pmaydell@chiark.greenend.org.uk>"
# Primary key fingerprint: E1A5 C593 CD41 9DE2 8E83  15CF 3C25 25ED 1436 0CDE

* remotes/pmaydell/tags/pull-target-arm-20181008: (33 commits)
  hw/display/bcm2835_fb: Silence Coverity warning about multiply overflow
  target/arm: Add v8M stack checks for MSR to SP_NS
  target/arm: Add v8M stack checks for VLDM/VSTM
  target/arm: Add v8M stack checks for Thumb push/pop
  target/arm: Add v8M stack checks for T32 load/store single
  target/arm: Add v8M stack checks for Thumb2 LDM/STM
  target/arm: Add v8M stack checks for LDRD/STRD (imm)
  target/arm: Add v8M stack limit checks on NS function calls
  target/arm: Add v8M stack checks on exception entry
  target/arm: Add some comments in Thumb decode
  target/arm: Add v8M stack checks on ADD/SUB/MOV of SP
  target/arm: Move v7m_using_psp() to internals.h
  target/arm: Define new EXCP type for v8M stack overflows
  target/arm: Define new TBFLAG for v8M stack checking
  target/arm: Pass TCGMemOpIdx to sve memory helpers
  target/arm: Rewrite vector gather first-fault loads
  target/arm: Rewrite vector gather stores
  target/arm: Rewrite vector gather loads
  target/arm: Split contiguous stores for endianness
  target/arm: Split contiguous loads for endianness
  ...

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

Author: pm215

hw/arm/virt.c

@@ -1926,6 +1926,8 @@ static void virt_machine_2_10_options(MachineClass *mc)
 {
     virt_machine_2_11_options(mc);
     SET_MACHINE_COMPAT(mc, VIRT_COMPAT_2_10);
+    /* before 2.11 we never faulted accesses to bad addresses */
+    mc->ignore_memory_transaction_failures = true;
 }
 DEFINE_VIRT_MACHINE(2, 10)
 

hw/display/bcm2835_fb.c

@@ -190,7 +190,7 @@ static void fb_update_display(void *opaque)
     }
 
     if (s->invalidate) {
-        hwaddr base = s->config.base + xoff + yoff * src_width;
+        hwaddr base = s->config.base + xoff + (hwaddr)yoff * src_width;
         framebuffer_update_memory_section(&s->fbsection, s->dma_mr,
                                           base,
                                           s->config.yres, src_width);

target/arm/cpu.h

@@ -56,6 +56,7 @@
 #define EXCP_SEMIHOST       16   /* semihosting call */
 #define EXCP_NOCP           17   /* v7M NOCP UsageFault */
 #define EXCP_INVSTATE       18   /* v7M INVSTATE UsageFault */
+#define EXCP_STKOF          19   /* v8M STKOF UsageFault */
 /* NB: add new EXCP_ defines to the array in arm_log_exception() too */
 
 #define ARMV7M_EXCP_RESET   1
@@ -910,12 +911,20 @@ int arm_cpu_write_elf32_note(WriteCoreDumpFunction f, CPUState *cs,
 int aarch64_cpu_gdb_read_register(CPUState *cpu, uint8_t *buf, int reg);
 int aarch64_cpu_gdb_write_register(CPUState *cpu, uint8_t *buf, int reg);
 void aarch64_sve_narrow_vq(CPUARMState *env, unsigned vq);
+void aarch64_sve_change_el(CPUARMState *env, int old_el, int new_el);
+#else
+static inline void aarch64_sve_narrow_vq(CPUARMState *env, unsigned vq) { }
+static inline void aarch64_sve_change_el(CPUARMState *env, int o, int n) { }
 #endif
 
 target_ulong do_arm_semihosting(CPUARMState *env);
 void aarch64_sync_32_to_64(CPUARMState *env);
 void aarch64_sync_64_to_32(CPUARMState *env);
 
+int fp_exception_el(CPUARMState *env, int cur_el);
+int sve_exception_el(CPUARMState *env, int cur_el);
+uint32_t sve_zcr_len_for_el(CPUARMState *env, int el);
+
 static inline bool is_a64(CPUARMState *env)
 {
     return env->aarch64;
@@ -1336,8 +1345,10 @@ FIELD(V7M_CCR, UNALIGN_TRP, 3, 1)
 FIELD(V7M_CCR, DIV_0_TRP, 4, 1)
 FIELD(V7M_CCR, BFHFNMIGN, 8, 1)
 FIELD(V7M_CCR, STKALIGN, 9, 1)
+FIELD(V7M_CCR, STKOFHFNMIGN, 10, 1)
 FIELD(V7M_CCR, DC, 16, 1)
 FIELD(V7M_CCR, IC, 17, 1)
+FIELD(V7M_CCR, BP, 18, 1)
 
 /* V7M SCR bits */
 FIELD(V7M_SCR, SLEEPONEXIT, 1, 1)
@@ -1378,6 +1389,7 @@ FIELD(V7M_CFSR, UNDEFINSTR, 16 + 0, 1)
 FIELD(V7M_CFSR, INVSTATE, 16 + 1, 1)
 FIELD(V7M_CFSR, INVPC, 16 + 2, 1)
 FIELD(V7M_CFSR, NOCP, 16 + 3, 1)
+FIELD(V7M_CFSR, STKOF, 16 + 4, 1)
 FIELD(V7M_CFSR, UNALIGNED, 16 + 8, 1)
 FIELD(V7M_CFSR, DIVBYZERO, 16 + 9, 1)
 
@@ -2842,6 +2854,9 @@ static inline bool arm_cpu_data_is_big_endian(CPUARMState *env)
 /* For M profile only, Handler (ie not Thread) mode */
 #define ARM_TBFLAG_HANDLER_SHIFT    21
 #define ARM_TBFLAG_HANDLER_MASK     (1 << ARM_TBFLAG_HANDLER_SHIFT)
+/* For M profile only, whether we should generate stack-limit checks */
+#define ARM_TBFLAG_STACKCHECK_SHIFT 22
+#define ARM_TBFLAG_STACKCHECK_MASK  (1 << ARM_TBFLAG_STACKCHECK_SHIFT)
 
 /* Bit usage when in AArch64 state */
 #define ARM_TBFLAG_TBI0_SHIFT 0        /* TBI0 for EL0/1 or TBI for EL2/3 */
@@ -2884,6 +2899,8 @@ static inline bool arm_cpu_data_is_big_endian(CPUARMState *env)
     (((F) & ARM_TBFLAG_BE_DATA_MASK) >> ARM_TBFLAG_BE_DATA_SHIFT)
 #define ARM_TBFLAG_HANDLER(F) \
     (((F) & ARM_TBFLAG_HANDLER_MASK) >> ARM_TBFLAG_HANDLER_SHIFT)
+#define ARM_TBFLAG_STACKCHECK(F) \
+    (((F) & ARM_TBFLAG_STACKCHECK_MASK) >> ARM_TBFLAG_STACKCHECK_SHIFT)
 #define ARM_TBFLAG_TBI0(F) \
     (((F) & ARM_TBFLAG_TBI0_MASK) >> ARM_TBFLAG_TBI0_SHIFT)
 #define ARM_TBFLAG_TBI1(F) \

target/arm/cpu64.c

@@ -410,45 +410,3 @@ static void aarch64_cpu_register_types(void)
 }
 
 type_init(aarch64_cpu_register_types)
-
-/* The manual says that when SVE is enabled and VQ is widened the
- * implementation is allowed to zero the previously inaccessible
- * portion of the registers.  The corollary to that is that when
- * SVE is enabled and VQ is narrowed we are also allowed to zero
- * the now inaccessible portion of the registers.
- *
- * The intent of this is that no predicate bit beyond VQ is ever set.
- * Which means that some operations on predicate registers themselves
- * may operate on full uint64_t or even unrolled across the maximum
- * uint64_t[4].  Performing 4 bits of host arithmetic unconditionally
- * may well be cheaper than conditionals to restrict the operation
- * to the relevant portion of a uint16_t[16].
- *
- * TODO: Need to call this for changes to the real system registers
- * and EL state changes.
- */
-void aarch64_sve_narrow_vq(CPUARMState *env, unsigned vq)
-{
-    int i, j;
-    uint64_t pmask;
-
-    assert(vq >= 1 && vq <= ARM_MAX_VQ);
-    assert(vq <= arm_env_get_cpu(env)->sve_max_vq);
-
-    /* Zap the high bits of the zregs.  */
-    for (i = 0; i < 32; i++) {
-        memset(&env->vfp.zregs[i].d[2 * vq], 0, 16 * (ARM_MAX_VQ - vq));
-    }
-
-    /* Zap the high bits of the pregs and ffr.  */
-    pmask = 0;
-    if (vq & 3) {
-        pmask = ~(-1ULL << (16 * (vq & 3)));
-    }
-    for (j = vq / 4; j < ARM_MAX_VQ / 4; j++) {
-        for (i = 0; i < 17; ++i) {
-            env->vfp.pregs[i].p[j] &= pmask;
-        }
-        pmask = 0;
-    }
-}