[Qemu-devel] [PATCH] arm-linux-user: fix elfload.c's AT_HWCAP reflected cpu features.

["Benoît Canet" <benoit.canet@gmail.com>]

The cpu capabilities passed by the elf loader in AT_HWCAP where
a constant.
Make AT_HWCAP reflect the emulated cpu features in order to give
correct clues to eglibc.

Fix :  [Bug 887516] [NEW] VFP support reported for the PXA270

Signed-off-by: Benoit Canet <benoit.canet@gmail.com>
---
 linux-user/elfload.c |   31 +++++++++++++++++++++++++++----
 1 files changed, 27 insertions(+), 4 deletions(-)

diff --git a/linux-user/elfload.c b/linux-user/elfload.c
index a413976..5d81ec1 100644
--- a/linux-user/elfload.c
+++ b/linux-user/elfload.c
@@ -375,10 +375,33 @@ bool guest_validate_base(unsigned long guest_base)
     return 1; /* All good */
 }
 
-#define ELF_HWCAP (ARM_HWCAP_ARM_SWP | ARM_HWCAP_ARM_HALF               \
-                   | ARM_HWCAP_ARM_THUMB | ARM_HWCAP_ARM_FAST_MULT      \
-                   | ARM_HWCAP_ARM_FPA | ARM_HWCAP_ARM_VFP              \
-                   | ARM_HWCAP_ARM_NEON | ARM_HWCAP_ARM_VFPv3 )
+
+#define ELF_HWCAP get_elf_hwcap()
+
+static uint32_t get_elf_hwcap(void)
+{
+    CPUState *e = thread_env;
+    uint32_t hwcaps = 0;
+
+    hwcaps |= ARM_HWCAP_ARM_SWP;
+    hwcaps |= ARM_HWCAP_ARM_HALF;
+    hwcaps |= ARM_HWCAP_ARM_THUMB;
+    hwcaps |= ARM_HWCAP_ARM_FAST_MULT;
+    hwcaps |= ARM_HWCAP_ARM_FPA;
+
+    /* prove for the extra features */
+#define GET_FEATURE(feat, hwcap) \
+    do {if (arm_feature(e, feat)) { hwcaps |= hwcap; } } while (0)
+    GET_FEATURE(ARM_FEATURE_VFP, ARM_HWCAP_ARM_VFP);
+    GET_FEATURE(ARM_FEATURE_IWMMXT, ARM_HWCAP_ARM_IWMMXT);
+    GET_FEATURE(ARM_FEATURE_THUMB2EE, ARM_HWCAP_ARM_THUMBEE);
+    GET_FEATURE(ARM_FEATURE_NEON, ARM_HWCAP_ARM_NEON);
+    GET_FEATURE(ARM_FEATURE_VFP3, ARM_HWCAP_ARM_VFPv3);
+    GET_FEATURE(ARM_FEATURE_VFP_FP16, ARM_HWCAP_ARM_VFPv3D16);
+#undef GET_FEATURE
+
+    return hwcaps;
+}
 
 #endif
 
-- 
1.7.5.4