[PATCH v4 1/5] target/sparc: Add FQ and FSR.QNE

[Richard Henderson <richard.henderson@linaro.org>]

From: Carl Hauser <chauser@pullman.com>

Add support for, and migrate, a single-entry fp
instruction queue for sparc32.

Signed-off-by: Carl Hauser <chauser@pullman.com>
[rth: Split from a larger patch;
      adjust representation with union;
      add migration state]
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 target/sparc/cpu.h        | 22 ++++++++++++++++++++++
 target/sparc/fop_helper.c |  4 ++++
 target/sparc/machine.c    | 25 +++++++++++++++++++++++++
 3 files changed, 51 insertions(+)

diff --git a/target/sparc/cpu.h b/target/sparc/cpu.h
index dfd9512a21..9f2bc44722 100644
--- a/target/sparc/cpu.h
+++ b/target/sparc/cpu.h
@@ -184,6 +184,8 @@ enum {
 #define FSR_FTT_SEQ_ERROR (4ULL << 14)
 #define FSR_FTT_INVAL_FPR (6ULL << 14)
 
+#define FSR_QNE    (1ULL << 13)
+
 #define FSR_FCC0_SHIFT    10
 #define FSR_FCC1_SHIFT    32
 #define FSR_FCC2_SHIFT    34
@@ -438,6 +440,26 @@ struct CPUArchState {
     uint32_t fsr_cexc_ftt;           /* cexc, ftt */
     uint32_t fcc[TARGET_FCCREGS];    /* fcc* */
 
+#if !defined(TARGET_SPARC64) && !defined(CONFIG_USER_ONLY)
+    /*
+     * Single-element FPU fault queue, with address and insn,
+     * packaged into the double-word with which it is stored.
+     */
+    uint32_t fsr_qne;                /* qne */
+    union {
+        uint64_t d;
+        struct {
+#if HOST_BIG_ENDIAN
+            uint32_t addr;
+            uint32_t insn;
+#else
+            uint32_t insn;
+            uint32_t addr;
+#endif
+        } s;
+    } fq;
+#endif
+
     CPU_DoubleU fpr[TARGET_DPREGS];  /* floating point registers */
     uint32_t cwp;      /* index of current register window (extracted
                           from PSR) */
diff --git a/target/sparc/fop_helper.c b/target/sparc/fop_helper.c
index 0b30665b51..b6692382b3 100644
--- a/target/sparc/fop_helper.c
+++ b/target/sparc/fop_helper.c
@@ -545,6 +545,8 @@ target_ulong cpu_get_fsr(CPUSPARCState *env)
     fsr |= (uint64_t)env->fcc[1] << FSR_FCC1_SHIFT;
     fsr |= (uint64_t)env->fcc[2] << FSR_FCC2_SHIFT;
     fsr |= (uint64_t)env->fcc[3] << FSR_FCC3_SHIFT;
+#elif !defined(CONFIG_USER_ONLY)
+    fsr |= env->fsr_qne;
 #endif
 
     /* VER is kept completely separate until re-assembly. */
@@ -591,6 +593,8 @@ void cpu_put_fsr(CPUSPARCState *env, target_ulong fsr)
     env->fcc[1] = extract64(fsr, FSR_FCC1_SHIFT, 2);
     env->fcc[2] = extract64(fsr, FSR_FCC2_SHIFT, 2);
     env->fcc[3] = extract64(fsr, FSR_FCC3_SHIFT, 2);
+#elif !defined(CONFIG_USER_ONLY)
+    env->fsr_qne = fsr & FSR_QNE;
 #endif
 
     set_fsr_nonsplit(env, fsr);
diff --git a/target/sparc/machine.c b/target/sparc/machine.c
index 48e0cf22f3..222e5709c5 100644
--- a/target/sparc/machine.c
+++ b/target/sparc/machine.c
@@ -143,6 +143,24 @@ static const VMStateInfo vmstate_xcc = {
     .get = get_xcc,
     .put = put_xcc,
 };
+#else
+static bool fq_needed(void *opaque)
+{
+    SPARCCPU *cpu = opaque;
+    return cpu->env.fsr_qne;
+}
+
+static const VMStateDescription vmstate_fq = {
+    .name = "cpu/fq",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .needed = fq_needed,
+    .fields = (const VMStateField[]) {
+        VMSTATE_UINT32(env.fq.s.addr, SPARCCPU),
+        VMSTATE_UINT32(env.fq.s.insn, SPARCCPU),
+        VMSTATE_END_OF_LIST()
+    },
+};
 #endif
 
 static int cpu_pre_save(void *opaque)
@@ -265,4 +283,11 @@ const VMStateDescription vmstate_sparc_cpu = {
 #endif
         VMSTATE_END_OF_LIST()
     },
+#ifndef TARGET_SPARC64
+    .subsections = (const VMStateDescription * const []) {
+        &vmstate_fq,
+        NULL
+    },
+#endif
+
 };
-- 
2.43.0