[Qemu-devel] [PATCH] sh4: Add SH bit handling to TLB.

[takasi-y]

This patch adds SH bit handling to sh4's TLB, which is a part of MMU
 functionality that had not been implemented in qemu.

Additionally, increment_urc() call in cpu_load_tlb() is deleted,
because the specification explicitly says that
  URC is not incremented by an LDTLB instruction.
(at Section 3 of SH7751 Hardware manual(REJ09B0370-0400)).
Even though URC is not needed to be strictly same as HW because it is a random
 number, this condition is not negligible.

Signed-off-by: Takashi YOSHII <address@hidden>
---
 target-sh4/helper.c |   12 ++++++------
 1 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/target-sh4/helper.c b/target-sh4/helper.c
index c2cc432..882bc9c 100644
--- a/target-sh4/helper.c
+++ b/target-sh4/helper.c
@@ -255,7 +255,7 @@ static int find_tlb_entry(CPUState * env, target_ulong 
address,
     for (i = 0; i < nbtlb; i++) {
        if (!entries[i].v)
            continue;           /* Invalid entry */
-       if (use_asid && entries[i].asid != asid)
+       if (!entries[i].sh && use_asid && entries[i].asid != asid)
            continue;           /* Bad ASID */
 #if 0
        switch (entries[i].sz) {
@@ -538,9 +538,6 @@ void cpu_load_tlb(CPUState * env)
        }
     }
 
-    /* per utlb access cannot implemented. */
-    increment_urc(env);
-
     /* Take values into cpu status from registers. */
     entry->asid = (uint8_t)cpu_pteh_asid(env->pteh);
     entry->vpn  = cpu_pteh_vpn(env->pteh);
@@ -581,6 +578,7 @@ void cpu_sh4_write_mmaped_utlb_addr(CPUSH4State *s, 
target_phys_addr_t addr,
     uint8_t d = (uint8_t)((mem_value & 0x00000200) >> 9);
     uint8_t v = (uint8_t)((mem_value & 0x00000100) >> 8);
     uint8_t asid = (uint8_t)(mem_value & 0x000000ff);
+    int use_asid = (s->mmucr & MMUCR_SV) == 0 || (s->sr & SR_MD) == 0;
 
     if (associate) {
         int i;
@@ -593,7 +591,8 @@ void cpu_sh4_write_mmaped_utlb_addr(CPUSH4State *s, 
target_phys_addr_t addr,
             if (!entry->v)
                continue;
 
-            if (entry->vpn == vpn && entry->asid == asid) {
+            if (entry->vpn == vpn
+                && (!use_asid || entry->asid == asid || entry->sh)) {
                if (utlb_match_entry) {
                    /* Multiple TLB Exception */
                    s->exception_index = 0x140;
@@ -612,7 +611,8 @@ void cpu_sh4_write_mmaped_utlb_addr(CPUSH4State *s, 
target_phys_addr_t addr,
        /* search ITLB */
        for (i = 0; i < ITLB_SIZE; i++) {
             tlb_t * entry = &s->itlb[i];
-            if (entry->vpn == vpn && entry->asid == asid) {
+            if (entry->vpn == vpn
+                && (!use_asid || entry->asid == asid || entry->sh)) {
                if (entry->v && !v)
                    needs_tlb_flush = 1;
                if (utlb_match_entry)
-- 
1.5.6.3

/yoshii