target-alpha: Fixes for alpha-linux syscalls.

1. Add correct definitions of error numbers.
2. Implement SYS_osf_sigprocmask
3. Implement SYS_osf_get/setsysinfo for IEEE_FP_CONTROL.

This last requires exposing the FPCR value to do_syscall.
Since this value is actually split up into the float_status,
expose routines from helper.c to access it.

Finally, also add a float_exception_mask field to float_status.
We don't actually use it to control delivery of exceptions to
the emulator yet, but simply hold the value that we placed there
when loading/storing the FPCR.

Signed-off-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>

3 files changed, 128 insertions, 39 deletions

diff --git a/target-alpha/cpu.h b/target-alpha/cpu.h
index ca9dfe2458..c0dff4bb87 100644
--- a/target-alpha/cpu.h
+++ b/target-alpha/cpu.h
@@ -139,6 +139,53 @@ enum {
     FP_ROUND_DYNAMIC = 0x3,
 };
 
+/* FPCR bits */
+#define FPCR_SUM		(1ULL << 63)
+#define FPCR_INED		(1ULL << 62)
+#define FPCR_UNFD		(1ULL << 61)
+#define FPCR_UNDZ		(1ULL << 60)
+#define FPCR_DYN_SHIFT		58
+#define FPCR_DYN_MASK		(3ULL << FPCR_DYN_SHIFT)
+#define FPCR_IOV		(1ULL << 57)
+#define FPCR_INE		(1ULL << 56)
+#define FPCR_UNF		(1ULL << 55)
+#define FPCR_OVF		(1ULL << 54)
+#define FPCR_DZE		(1ULL << 53)
+#define FPCR_INV		(1ULL << 52)
+#define FPCR_OVFD		(1ULL << 51)
+#define FPCR_DZED		(1ULL << 50)
+#define FPCR_INVD		(1ULL << 49)
+#define FPCR_DNZ		(1ULL << 48)
+#define FPCR_DNOD		(1ULL << 47)
+#define FPCR_STATUS_MASK	(FPCR_IOV | FPCR_INE | FPCR_UNF \
+				 | FPCR_OVF | FPCR_DZE | FPCR_INV)
+
+/* The silly software trap enables implemented by the kernel emulation.
+   These are more or less architecturally required, since the real hardware
+   has read-as-zero bits in the FPCR when the features aren't implemented.
+   For the purposes of QEMU, we pretend the FPCR can hold everything.  */
+#define SWCR_TRAP_ENABLE_INV	(1ULL << 1)
+#define SWCR_TRAP_ENABLE_DZE	(1ULL << 2)
+#define SWCR_TRAP_ENABLE_OVF	(1ULL << 3)
+#define SWCR_TRAP_ENABLE_UNF	(1ULL << 4)
+#define SWCR_TRAP_ENABLE_INE	(1ULL << 5)
+#define SWCR_TRAP_ENABLE_DNO	(1ULL << 6)
+#define SWCR_TRAP_ENABLE_MASK	((1ULL << 7) - (1ULL << 1))
+
+#define SWCR_MAP_DMZ		(1ULL << 12)
+#define SWCR_MAP_UMZ		(1ULL << 13)
+#define SWCR_MAP_MASK		(SWCR_MAP_DMZ | SWCR_MAP_UMZ)
+
+#define SWCR_STATUS_INV		(1ULL << 17)
+#define SWCR_STATUS_DZE		(1ULL << 18)
+#define SWCR_STATUS_OVF		(1ULL << 19)
+#define SWCR_STATUS_UNF		(1ULL << 20)
+#define SWCR_STATUS_INE		(1ULL << 21)
+#define SWCR_STATUS_DNO		(1ULL << 22)
+#define SWCR_STATUS_MASK	((1ULL << 23) - (1ULL << 17))
+
+#define SWCR_MASK  (SWCR_TRAP_ENABLE_MASK | SWCR_MAP_MASK | SWCR_STATUS_MASK)
+
 /* Internal processor registers */
 /* XXX: TOFIX: most of those registers are implementation dependant */
 enum {
@@ -436,6 +483,8 @@ int cpu_alpha_handle_mmu_fault (CPUState *env, uint64_t address, int rw,
 #define cpu_handle_mmu_fault cpu_alpha_handle_mmu_fault
 void do_interrupt (CPUState *env);
 
+uint64_t cpu_alpha_load_fpcr (CPUState *env);
+void cpu_alpha_store_fpcr (CPUState *env, uint64_t val);
 int cpu_alpha_mfpr (CPUState *env, int iprn, uint64_t *valp);
 int cpu_alpha_mtpr (CPUState *env, int iprn, uint64_t val, uint64_t *oldvalp);
 void pal_init (CPUState *env);
diff --git a/target-alpha/helper.c b/target-alpha/helper.c
index fcd5841e01..a658f9782a 100644
--- a/target-alpha/helper.c
+++ b/target-alpha/helper.c
@@ -23,6 +23,83 @@
 
 #include "cpu.h"
 #include "exec-all.h"
+#include "softfloat.h"
+
+uint64_t cpu_alpha_load_fpcr (CPUState *env)
+{
+    uint64_t ret = 0;
+    int flags, mask;
+
+    flags = env->fp_status.float_exception_flags;
+    ret |= (uint64_t) flags << 52;
+    if (flags)
+        ret |= FPCR_SUM;
+    env->ipr[IPR_EXC_SUM] &= ~0x3E;
+    env->ipr[IPR_EXC_SUM] |= flags << 1;
+
+    mask = env->fp_status.float_exception_mask;
+    if (mask & float_flag_invalid)
+        ret |= FPCR_INVD;
+    if (mask & float_flag_divbyzero)
+        ret |= FPCR_DZED;
+    if (mask & float_flag_overflow)
+        ret |= FPCR_OVFD;
+    if (mask & float_flag_underflow)
+        ret |= FPCR_UNFD;
+    if (mask & float_flag_inexact)
+        ret |= FPCR_INED;
+
+    switch (env->fp_status.float_rounding_mode) {
+    case float_round_nearest_even:
+        ret |= 2ULL << FPCR_DYN_SHIFT;
+        break;
+    case float_round_down:
+        ret |= 1ULL << FPCR_DYN_SHIFT;
+        break;
+    case float_round_up:
+        ret |= 3ULL << FPCR_DYN_SHIFT;
+        break;
+    case float_round_to_zero:
+        break;
+    }
+    return ret;
+}
+
+void cpu_alpha_store_fpcr (CPUState *env, uint64_t val)
+{
+    int round_mode, mask;
+
+    set_float_exception_flags((val >> 52) & 0x3F, &env->fp_status);
+
+    mask = 0;
+    if (val & FPCR_INVD)
+        mask |= float_flag_invalid;
+    if (val & FPCR_DZED)
+        mask |= float_flag_divbyzero;
+    if (val & FPCR_OVFD)
+        mask |= float_flag_overflow;
+    if (val & FPCR_UNFD)
+        mask |= float_flag_underflow;
+    if (val & FPCR_INED)
+        mask |= float_flag_inexact;
+    env->fp_status.float_exception_mask = mask;
+
+    switch ((val >> FPCR_DYN_SHIFT) & 3) {
+    case 0:
+        round_mode = float_round_to_zero;
+        break;
+    case 1:
+        round_mode = float_round_down;
+        break;
+    case 2:
+        round_mode = float_round_nearest_even;
+        break;
+    case 3:
+        round_mode = float_round_up;
+        break;
+    }
+    set_float_rounding_mode(round_mode, &env->fp_status);
+}
 
 #if defined(CONFIG_USER_ONLY)
 
diff --git a/target-alpha/op_helper.c b/target-alpha/op_helper.c
index 508272c85d..999a8ab46c 100644
--- a/target-alpha/op_helper.c
+++ b/target-alpha/op_helper.c
@@ -39,49 +39,12 @@ uint64_t helper_load_pcc (void)
 
 uint64_t helper_load_fpcr (void)
 {
-    uint64_t ret = 0;
-#ifdef CONFIG_SOFTFLOAT
-    ret |= env->fp_status.float_exception_flags << 52;
-    if (env->fp_status.float_exception_flags)
-        ret |= 1ULL << 63;
-    env->ipr[IPR_EXC_SUM] &= ~0x3E:
-    env->ipr[IPR_EXC_SUM] |= env->fp_status.float_exception_flags << 1;
-#endif
-    switch (env->fp_status.float_rounding_mode) {
-    case float_round_nearest_even:
-        ret |= 2ULL << 58;
-        break;
-    case float_round_down:
-        ret |= 1ULL << 58;
-        break;
-    case float_round_up:
-        ret |= 3ULL << 58;
-        break;
-    case float_round_to_zero:
-        break;
-    }
-    return ret;
+    return cpu_alpha_load_fpcr (env);
 }
 
 void helper_store_fpcr (uint64_t val)
 {
-#ifdef CONFIG_SOFTFLOAT
-    set_float_exception_flags((val >> 52) & 0x3F, &FP_STATUS);
-#endif
-    switch ((val >> 58) & 3) {
-    case 0:
-        set_float_rounding_mode(float_round_to_zero, &FP_STATUS);
-        break;
-    case 1:
-        set_float_rounding_mode(float_round_down, &FP_STATUS);
-        break;
-    case 2:
-        set_float_rounding_mode(float_round_nearest_even, &FP_STATUS);
-        break;
-    case 3:
-        set_float_rounding_mode(float_round_up, &FP_STATUS);
-        break;
-    }
+    cpu_alpha_store_fpcr (env, val);
 }
 
 static spinlock_t intr_cpu_lock = SPIN_LOCK_UNLOCKED;