[Qemu-devel] [PATCH 2/7] SPARC64: SFSR cleanup and fix

[Tsuneo Saito <tsnsaito@gmail.com>]

Add macros for SFSR fields and use macros instead of magic numbers.
Also fix the update of the register fields on MMU faults.

Signed-off-by: Tsuneo Saito <tsnsaito@gmail.com>
---
 target-sparc/cpu.h    |   22 ++++++++++++++++++++
 target-sparc/helper.c |   52 +++++++++++++++++++++++++++++++++++++-----------
 2 files changed, 62 insertions(+), 12 deletions(-)

diff --git a/target-sparc/cpu.h b/target-sparc/cpu.h
index b2160e9..348858e 100644
--- a/target-sparc/cpu.h
+++ b/target-sparc/cpu.h
@@ -309,6 +309,28 @@ enum {
 #define TTE_PGSIZE(tte)     (((tte) >> 61) & 3ULL)
 #define TTE_PA(tte)         ((tte) & 0x1ffffffe000ULL)
 
+#define SFSR_NF_BIT         (1ULL << 24)   /* JPS1 NoFault */
+#define SFSR_TM_BIT         (1ULL << 15)   /* JPS1 TLB Miss */
+#define SFSR_FT_VA_IMMU_BIT (1ULL << 13)   /* USIIi VA out of range (IMMU) */
+#define SFSR_FT_VA_DMMU_BIT (1ULL << 12)   /* USIIi VA out of range (DMMU) */
+#define SFSR_FT_NFO_BIT     (1ULL << 11)   /* NFO page access */
+#define SFSR_FT_ILL_BIT     (1ULL << 10)   /* illegal LDA/STA ASI */
+#define SFSR_FT_ATOMIC_BIT  (1ULL <<  9)   /* atomic op on noncacheable area */
+#define SFSR_FT_NF_E_BIT    (1ULL <<  8)   /* NF access on side effect area */
+#define SFSR_FT_PRIV_BIT    (1ULL <<  7)   /* privilege violation */
+#define SFSR_PR_BIT         (1ULL <<  3)   /* privilege mode */
+#define SFSR_WRITE_BIT      (1ULL <<  2)   /* write access mode */
+#define SFSR_OW_BIT         (1ULL <<  1)   /* status overwritten */
+#define SFSR_VALID_BIT      (1ULL <<  0)   /* status valid */
+
+#define SFSR_ASI_SHIFT      16             /* 23:16 ASI value */
+#define SFSR_ASI_MASK       (0xffULL << SFSR_ASI_SHIFT)
+#define SFSR_CT_PRIMARY     (0ULL <<  4)   /* 5:4 context type */
+#define SFSR_CT_SECONDARY   (1ULL <<  4)
+#define SFSR_CT_NUCLEUS     (2ULL <<  4)
+#define SFSR_CT_NOTRANS     (3ULL <<  4)
+#define SFSR_CT_MASK        (3ULL <<  4)
+
 typedef struct SparcTLBEntry {
     uint64_t tag;
     uint64_t tte;
diff --git a/target-sparc/helper.c b/target-sparc/helper.c
index 0a4cfc5..f9b7fe2 100644
--- a/target-sparc/helper.c
+++ b/target-sparc/helper.c
@@ -413,6 +413,7 @@ static int get_physical_address_data(CPUState *env,
 {
     unsigned int i;
     uint64_t context;
+    uint64_t sfsr = 0;
 
     int is_user = (mmu_idx == MMU_USER_IDX ||
                    mmu_idx == MMU_USER_SECONDARY_IDX);
@@ -427,26 +428,32 @@ static int get_physical_address_data(CPUState *env,
     case MMU_USER_IDX:
     case MMU_KERNEL_IDX:
         context = env->dmmu.mmu_primary_context & 0x1fff;
+        sfsr |= SFSR_CT_PRIMARY;
         break;
     case MMU_USER_SECONDARY_IDX:
     case MMU_KERNEL_SECONDARY_IDX:
         context = env->dmmu.mmu_secondary_context & 0x1fff;
+        sfsr |= SFSR_CT_SECONDARY;
         break;
     case MMU_NUCLEUS_IDX:
+        sfsr |= SFSR_CT_NUCLEUS;
+        /* FALLTHRU */
     default:
         context = 0;
         break;
     }
 
+    if (rw == 1) {
+        sfsr |= SFSR_WRITE_BIT;
+    }
+
     for (i = 0; i < 64; i++) {
         // ctx match, vaddr match, valid?
         if (ultrasparc_tag_match(&env->dtlb[i], address, context, physical)) {
 
-            uint8_t fault_type = 0;
-
             // access ok?
             if (TTE_IS_PRIV(env->dtlb[i].tte) && is_user) {
-                fault_type |= 1; /* privilege violation */
+                sfsr |= SFSR_FT_PRIV_BIT; /* privilege violation */
                 env->exception_index = TT_DFAULT;
 
                 DPRINTF_MMU("DFAULT at %" PRIx64 " context %" PRIx64
@@ -469,13 +476,17 @@ static int get_physical_address_data(CPUState *env,
                 return 0;
             }
 
-            if (env->dmmu.sfsr & 1) /* Fault status register */
-                env->dmmu.sfsr = 2; /* overflow (not read before
-                                             another fault) */
+            if (env->dmmu.sfsr & SFSR_VALID_BIT) { /* Fault status register */
+                sfsr |= SFSR_OW_BIT; /* overflow (not read before
+                                        another fault) */
+            }
 
-            env->dmmu.sfsr |= (is_user << 3) | ((rw == 1) << 2) | 1;
+            if (env->pstate & PS_PRIV) {
+                sfsr |= SFSR_PR_BIT;
+            }
 
-            env->dmmu.sfsr |= (fault_type << 7);
+            /* FIXME: ASI field in SFSR must be set */
+            env->dmmu.sfsr = sfsr | SFSR_VALID_BIT;
 
             env->dmmu.sfar = address; /* Fault address register */
 
@@ -488,6 +499,11 @@ static int get_physical_address_data(CPUState *env,
     DPRINTF_MMU("DMISS at %" PRIx64 " context %" PRIx64 "\n",
                 address, context);
 
+    /*
+     * On MMU misses:
+     * - UltraSPARC IIi: SFSR and SFAR unmodified
+     * - JPS1: SFAR updated and some fields of SFSR updated
+     */
     env->dmmu.tag_access = (address & ~0x1fffULL) | context;
     env->exception_index = TT_DMISS;
     return 1;
@@ -524,10 +540,22 @@ static int get_physical_address_code(CPUState *env,
                                  address, context, physical)) {
             // access ok?
             if (TTE_IS_PRIV(env->itlb[i].tte) && is_user) {
-                if (env->immu.sfsr) /* Fault status register */
-                    env->immu.sfsr = 2; /* overflow (not read before
-                                             another fault) */
-                env->immu.sfsr |= (is_user << 3) | 1;
+                /* Fault status register */
+                if (env->immu.sfsr & SFSR_VALID_BIT) {
+                    env->immu.sfsr = SFSR_OW_BIT; /* overflow (not read before
+                                                     another fault) */
+                } else {
+                    env->immu.sfsr = 0;
+                }
+                if (env->pstate & PS_PRIV) {
+                    env->immu.sfsr |= SFSR_PR_BIT;
+                }
+                if (env->tl > 0) {
+                    env->immu.sfsr |= SFSR_CT_NUCLEUS;
+                }
+
+                /* FIXME: ASI field in SFSR must be set */
+                env->immu.sfsr |= SFSR_FT_PRIV_BIT | SFSR_VALID_BIT;
                 env->exception_index = TT_TFAULT;
 
                 env->immu.tag_access = (address & ~0x1fffULL) | context;
-- 
1.7.5.4