[Qemu-devel] [PATCH 14/45] target-ppc: Disentangle BAT code for 32-bit hash MMUs

[David Gibson]

The functions for looking up BATs (Block Address Translation - essentially
a level 0 TLB) are shared between the classic 32-bit hash MMUs and the
6xx style software loaded TLB implementations.

This patch splits out a copy for the 32-bit hash MMUs, to facilitate
cleaning it up.  The remaining version is left, but cleaned up slightly
to no longer deal with PowerPC 601 peculiarities (601 has a hash MMU).

Signed-off-by: David Gibson <address@hidden>
---
 target-ppc/cpu.h        |    2 -
 target-ppc/mmu-hash32.c |  140 ++++++++++++++++++++++++++++++++++++++++++++++-
 target-ppc/mmu_helper.c |   38 ++-----------
 3 files changed, 142 insertions(+), 38 deletions(-)

diff --git a/target-ppc/cpu.h b/target-ppc/cpu.h
index bf3ec02..11a3087 100644
--- a/target-ppc/cpu.h
+++ b/target-ppc/cpu.h
@@ -1154,8 +1154,6 @@ void ppc_hw_interrupt (CPUPPCState *env);
 
 #if !defined(CONFIG_USER_ONLY)
 void ppc_store_sdr1 (CPUPPCState *env, target_ulong value);
-int get_bat(CPUPPCState *env, mmu_ctx_t *ctx,
-            target_ulong virtual, int rw, int type);
 #endif /* !defined(CONFIG_USER_ONLY) */
 void ppc_store_msr (CPUPPCState *env, target_ulong value);
 
diff --git a/target-ppc/mmu-hash32.c b/target-ppc/mmu-hash32.c
index 0ccaf7c..f94b65d 100644
--- a/target-ppc/mmu-hash32.c
+++ b/target-ppc/mmu-hash32.c
@@ -25,6 +25,7 @@
 #include "mmu-hash32.h"
 
 //#define DEBUG_MMU
+//#define DEBUG_BAT
 
 #ifdef DEBUG_MMU
 #  define LOG_MMU(...) qemu_log(__VA_ARGS__)
@@ -34,6 +35,12 @@
 #  define LOG_MMU_STATE(...) do { } while (0)
 #endif
 
+#ifdef DEBUG_BATS
+#  define LOG_BATS(...) qemu_log(__VA_ARGS__)
+#else
+#  define LOG_BATS(...) do { } while (0)
+#endif
+
 #define PTE_PTEM_MASK 0x7FFFFFBF
 #define PTE_CHECK_MASK (TARGET_PAGE_MASK | 0x7B)
 
@@ -102,6 +109,136 @@ static int ppc_hash32_check_prot(int prot, int rw, int 
access_type)
     return ret;
 }
 
+/* Perform BAT hit & translation */
+static void hash32_bat_size_prot(CPUPPCState *env, target_ulong *blp,
+                                 int *validp, int *protp, target_ulong *BATu,
+                                 target_ulong *BATl)
+{
+    target_ulong bl;
+    int pp, valid, prot;
+
+    bl = (*BATu & 0x00001FFC) << 15;
+    valid = 0;
+    prot = 0;
+    if (((msr_pr == 0) && (*BATu & 0x00000002)) ||
+        ((msr_pr != 0) && (*BATu & 0x00000001))) {
+        valid = 1;
+        pp = *BATl & 0x00000003;
+        if (pp != 0) {
+            prot = PAGE_READ | PAGE_EXEC;
+            if (pp == 0x2) {
+                prot |= PAGE_WRITE;
+            }
+        }
+    }
+    *blp = bl;
+    *validp = valid;
+    *protp = prot;
+}
+
+static void hash32_bat_601_size_prot(CPUPPCState *env, target_ulong *blp,
+                                     int *validp, int *protp,
+                                     target_ulong *BATu, target_ulong *BATl)
+{
+    target_ulong bl;
+    int key, pp, valid, prot;
+
+    bl = (*BATl & 0x0000003F) << 17;
+    LOG_BATS("b %02x ==> bl " TARGET_FMT_lx " msk " TARGET_FMT_lx "\n",
+             (uint8_t)(*BATl & 0x0000003F), bl, ~bl);
+    prot = 0;
+    valid = (*BATl >> 6) & 1;
+    if (valid) {
+        pp = *BATu & 0x00000003;
+        if (msr_pr == 0) {
+            key = (*BATu >> 3) & 1;
+        } else {
+            key = (*BATu >> 2) & 1;
+        }
+        prot = ppc_hash32_pp_check(key, pp, 0);
+    }
+    *blp = bl;
+    *validp = valid;
+    *protp = prot;
+}
+
+static int ppc_hash32_get_bat(CPUPPCState *env, mmu_ctx_t *ctx,
+                              target_ulong virtual, int rw, int type)
+{
+    target_ulong *BATlt, *BATut, *BATu, *BATl;
+    target_ulong BEPIl, BEPIu, bl;
+    int i, valid, prot;
+    int ret = -1;
+
+    LOG_BATS("%s: %cBAT v " TARGET_FMT_lx "\n", __func__,
+             type == ACCESS_CODE ? 'I' : 'D', virtual);
+    switch (type) {
+    case ACCESS_CODE:
+        BATlt = env->IBAT[1];
+        BATut = env->IBAT[0];
+        break;
+    default:
+        BATlt = env->DBAT[1];
+        BATut = env->DBAT[0];
+        break;
+    }
+    for (i = 0; i < env->nb_BATs; i++) {
+        BATu = &BATut[i];
+        BATl = &BATlt[i];
+        BEPIu = *BATu & 0xF0000000;
+        BEPIl = *BATu & 0x0FFE0000;
+        if (unlikely(env->mmu_model == POWERPC_MMU_601)) {
+            hash32_bat_601_size_prot(env, &bl, &valid, &prot, BATu, BATl);
+        } else {
+            hash32_bat_size_prot(env, &bl, &valid, &prot, BATu, BATl);
+        }
+        LOG_BATS("%s: %cBAT%d v " TARGET_FMT_lx " BATu " TARGET_FMT_lx
+                 " BATl " TARGET_FMT_lx "\n", __func__,
+                 type == ACCESS_CODE ? 'I' : 'D', i, virtual, *BATu, *BATl);
+        if ((virtual & 0xF0000000) == BEPIu &&
+            ((virtual & 0x0FFE0000) & ~bl) == BEPIl) {
+            /* BAT matches */
+            if (valid != 0) {
+                /* Get physical address */
+                ctx->raddr = (*BATl & 0xF0000000) |
+                    ((virtual & 0x0FFE0000 & bl) | (*BATl & 0x0FFE0000)) |
+                    (virtual & 0x0001F000);
+                /* Compute access rights */
+                ctx->prot = prot;
+                ret = ppc_hash32_check_prot(ctx->prot, rw, type);
+                if (ret == 0) {
+                    LOG_BATS("BAT %d match: r " TARGET_FMT_plx " prot=%c%c\n",
+                             i, ctx->raddr, ctx->prot & PAGE_READ ? 'R' : '-',
+                             ctx->prot & PAGE_WRITE ? 'W' : '-');
+                }
+                break;
+            }
+        }
+    }
+    if (ret < 0) {
+#if defined(DEBUG_BATS)
+        if (qemu_log_enabled()) {
+            LOG_BATS("no BAT match for " TARGET_FMT_lx ":\n", virtual);
+            for (i = 0; i < 4; i++) {
+                BATu = &BATut[i];
+                BATl = &BATlt[i];
+                BEPIu = *BATu & 0xF0000000;
+                BEPIl = *BATu & 0x0FFE0000;
+                bl = (*BATu & 0x00001FFC) << 15;
+                LOG_BATS("%s: %cBAT%d v " TARGET_FMT_lx " BATu " TARGET_FMT_lx
+                         " BATl " TARGET_FMT_lx "\n\t" TARGET_FMT_lx " "
+                         TARGET_FMT_lx " " TARGET_FMT_lx "\n",
+                         __func__, type == ACCESS_CODE ? 'I' : 'D', i, virtual,
+                         *BATu, *BATl, BEPIu, BEPIl, bl);
+            }
+        }
+#endif
+    }
+    /* No hit */
+    return ret;
+}
+
+
 static inline int pte_is_valid_hash32(target_ulong pte0)
 {
     return pte0 & 0x80000000 ? 1 : 0;
@@ -398,7 +535,6 @@ static int get_segment32(CPUPPCState *env, mmu_ctx_t *ctx,
     return ret;
 }
 
-
 static int ppc_hash32_get_physical_address(CPUPPCState *env, mmu_ctx_t *ctx,
                                            target_ulong eaddr, int rw,
                                            int access_type)
@@ -415,7 +551,7 @@ static int ppc_hash32_get_physical_address(CPUPPCState 
*env, mmu_ctx_t *ctx,
 
         /* Try to find a BAT */
         if (env->nb_BATs != 0) {
-            ret = get_bat(env, ctx, eaddr, rw, access_type);
+            ret = ppc_hash32_get_bat(env, ctx, eaddr, rw, access_type);
         }
         if (ret < 0) {
             /* We didn't match any BAT entry or don't have BATs */
diff --git a/target-ppc/mmu_helper.c b/target-ppc/mmu_helper.c
index 50ec0ac..9471d59 100644
--- a/target-ppc/mmu_helper.c
+++ b/target-ppc/mmu_helper.c
@@ -397,34 +397,8 @@ static inline void bat_size_prot(CPUPPCState *env, 
target_ulong *blp,
     *protp = prot;
 }
 
-static inline void bat_601_size_prot(CPUPPCState *env, target_ulong *blp,
-                                     int *validp, int *protp,
-                                     target_ulong *BATu, target_ulong *BATl)
-{
-    target_ulong bl;
-    int key, pp, valid, prot;
-
-    bl = (*BATl & 0x0000003F) << 17;
-    LOG_BATS("b %02x ==> bl " TARGET_FMT_lx " msk " TARGET_FMT_lx "\n",
-             (uint8_t)(*BATl & 0x0000003F), bl, ~bl);
-    prot = 0;
-    valid = (*BATl >> 6) & 1;
-    if (valid) {
-        pp = *BATu & 0x00000003;
-        if (msr_pr == 0) {
-            key = (*BATu >> 3) & 1;
-        } else {
-            key = (*BATu >> 2) & 1;
-        }
-        prot = pp_check(key, pp, 0);
-    }
-    *blp = bl;
-    *validp = valid;
-    *protp = prot;
-}
-
-int get_bat(CPUPPCState *env, mmu_ctx_t *ctx,
-            target_ulong virtual, int rw, int type)
+static int get_bat_6xx_tlb(CPUPPCState *env, mmu_ctx_t *ctx,
+                           target_ulong virtual, int rw, int type)
 {
     target_ulong *BATlt, *BATut, *BATu, *BATl;
     target_ulong BEPIl, BEPIu, bl;
@@ -448,11 +422,7 @@ int get_bat(CPUPPCState *env, mmu_ctx_t *ctx,
         BATl = &BATlt[i];
         BEPIu = *BATu & 0xF0000000;
         BEPIl = *BATu & 0x0FFE0000;
-        if (unlikely(env->mmu_model == POWERPC_MMU_601)) {
-            bat_601_size_prot(env, &bl, &valid, &prot, BATu, BATl);
-        } else {
-            bat_size_prot(env, &bl, &valid, &prot, BATu, BATl);
-        }
+        bat_size_prot(env, &bl, &valid, &prot, BATu, BATl);
         LOG_BATS("%s: %cBAT%d v " TARGET_FMT_lx " BATu " TARGET_FMT_lx
                  " BATl " TARGET_FMT_lx "\n", __func__,
                  type == ACCESS_CODE ? 'I' : 'D', i, virtual, *BATu, *BATl);
@@ -1309,7 +1279,7 @@ static int get_physical_address(CPUPPCState *env, 
mmu_ctx_t *ctx,
         } else {
             /* Try to find a BAT */
             if (env->nb_BATs != 0) {
-                ret = get_bat(env, ctx, eaddr, rw, access_type);
+                ret = get_bat_6xx_tlb(env, ctx, eaddr, rw, access_type);
             }
             if (ret < 0) {
                 /* We didn't match any BAT entry or don't have BATs */
-- 
1.7.10.4