[Qemu-devel] [PULL 04/20] target/arm: Enforce FP access to FPCR/FPSR

[Peter Maydell]

From: Richard Henderson <address@hidden>

Signed-off-by: Richard Henderson <address@hidden>
Message-id: address@hidden
Reviewed-by: Peter Maydell <address@hidden>
Signed-off-by: Peter Maydell <address@hidden>
---
 target/arm/cpu.h           | 35 ++++++++++++++++++-----------------
 target/arm/helper.c        |  6 ++++--
 target/arm/translate-a64.c |  3 +++
 3 files changed, 25 insertions(+), 19 deletions(-)

diff --git a/target/arm/cpu.h b/target/arm/cpu.h
index 521444a5a1..e966a57f8a 100644
--- a/target/arm/cpu.h
+++ b/target/arm/cpu.h
@@ -1714,7 +1714,7 @@ static inline uint64_t cpreg_to_kvm_id(uint32_t cpregid)
 }
 
 /* ARMCPRegInfo type field bits. If the SPECIAL bit is set this is a
- * special-behaviour cp reg and bits [15..8] indicate what behaviour
+ * special-behaviour cp reg and bits [11..8] indicate what behaviour
  * it has. Otherwise it is a simple cp reg, where CONST indicates that
  * TCG can assume the value to be constant (ie load at translate time)
  * and 64BIT indicates a 64 bit wide coprocessor register. SUPPRESS_TB_END
@@ -1735,24 +1735,25 @@ static inline uint64_t cpreg_to_kvm_id(uint32_t cpregid)
  * need to be surrounded by gen_io_start()/gen_io_end(). In particular,
  * registers which implement clocks or timers require this.
  */
-#define ARM_CP_SPECIAL 1
-#define ARM_CP_CONST 2
-#define ARM_CP_64BIT 4
-#define ARM_CP_SUPPRESS_TB_END 8
-#define ARM_CP_OVERRIDE 16
-#define ARM_CP_ALIAS 32
-#define ARM_CP_IO 64
-#define ARM_CP_NO_RAW 128
-#define ARM_CP_NOP (ARM_CP_SPECIAL | (1 << 8))
-#define ARM_CP_WFI (ARM_CP_SPECIAL | (2 << 8))
-#define ARM_CP_NZCV (ARM_CP_SPECIAL | (3 << 8))
-#define ARM_CP_CURRENTEL (ARM_CP_SPECIAL | (4 << 8))
-#define ARM_CP_DC_ZVA (ARM_CP_SPECIAL | (5 << 8))
-#define ARM_LAST_SPECIAL ARM_CP_DC_ZVA
+#define ARM_CP_SPECIAL           0x0001
+#define ARM_CP_CONST             0x0002
+#define ARM_CP_64BIT             0x0004
+#define ARM_CP_SUPPRESS_TB_END   0x0008
+#define ARM_CP_OVERRIDE          0x0010
+#define ARM_CP_ALIAS             0x0020
+#define ARM_CP_IO                0x0040
+#define ARM_CP_NO_RAW            0x0080
+#define ARM_CP_NOP               (ARM_CP_SPECIAL | 0x0100)
+#define ARM_CP_WFI               (ARM_CP_SPECIAL | 0x0200)
+#define ARM_CP_NZCV              (ARM_CP_SPECIAL | 0x0300)
+#define ARM_CP_CURRENTEL         (ARM_CP_SPECIAL | 0x0400)
+#define ARM_CP_DC_ZVA            (ARM_CP_SPECIAL | 0x0500)
+#define ARM_LAST_SPECIAL         ARM_CP_DC_ZVA
+#define ARM_CP_FPU               0x1000
 /* Used only as a terminator for ARMCPRegInfo lists */
-#define ARM_CP_SENTINEL 0xffff
+#define ARM_CP_SENTINEL          0xffff
 /* Mask of only the flag bits in a type field */
-#define ARM_CP_FLAG_MASK 0xff
+#define ARM_CP_FLAG_MASK         0x10ff
 
 /* Valid values for ARMCPRegInfo state field, indicating which of
  * the AArch32 and AArch64 execution states this register is visible in.
diff --git a/target/arm/helper.c b/target/arm/helper.c
index 4b102ec356..d41fb8371f 100644
--- a/target/arm/helper.c
+++ b/target/arm/helper.c
@@ -3356,10 +3356,12 @@ static const ARMCPRegInfo v8_cp_reginfo[] = {
       .writefn = aa64_daif_write, .resetfn = arm_cp_reset_ignore },
     { .name = "FPCR", .state = ARM_CP_STATE_AA64,
       .opc0 = 3, .opc1 = 3, .opc2 = 0, .crn = 4, .crm = 4,
-      .access = PL0_RW, .readfn = aa64_fpcr_read, .writefn = aa64_fpcr_write },
+      .access = PL0_RW, .type = ARM_CP_FPU,
+      .readfn = aa64_fpcr_read, .writefn = aa64_fpcr_write },
     { .name = "FPSR", .state = ARM_CP_STATE_AA64,
       .opc0 = 3, .opc1 = 3, .opc2 = 1, .crn = 4, .crm = 4,
-      .access = PL0_RW, .readfn = aa64_fpsr_read, .writefn = aa64_fpsr_write },
+      .access = PL0_RW, .type = ARM_CP_FPU,
+      .readfn = aa64_fpsr_read, .writefn = aa64_fpsr_write },
     { .name = "DCZID_EL0", .state = ARM_CP_STATE_AA64,
       .opc0 = 3, .opc1 = 3, .opc2 = 7, .crn = 0, .crm = 0,
       .access = PL0_R, .type = ARM_CP_NO_RAW,
diff --git a/target/arm/translate-a64.c b/target/arm/translate-a64.c
index fb1a4cb532..89f50558a7 100644
--- a/target/arm/translate-a64.c
+++ b/target/arm/translate-a64.c
@@ -1631,6 +1631,9 @@ static void handle_sys(DisasContext *s, uint32_t insn, 
bool isread,
     default:
         break;
     }
+    if ((ri->type & ARM_CP_FPU) && !fp_access_check(s)) {
+        return;
+    }
 
     if ((tb_cflags(s->base.tb) & CF_USE_ICOUNT) && (ri->type & ARM_CP_IO)) {
         gen_io_start();
-- 
2.16.1