Re: [PATCH v4 03/19] target/loongarch: Set page size in TLB entry with STLB

[gaosong]

在 2025/7/30 上午11:01, Bibo Mao 写道:

With VTLB different TLB entry may have different page size, and
page size is set in PS field of TLB entry. However with STLB, all
the TLB entries have the same page size, page size comes from register
CSR_STLBPS, PS field of TLB entry is not used.

Here PS field of TLB entry is used with all TLB entries, even with
STLB. It is convenient with TLB maintainance operation.

Signed-off-by: Bibo Mao <maob...@loongson.cn>
---
  target/loongarch/tcg/tlb_helper.c | 41 ++++++++-----------------------
  1 file changed, 10 insertions(+), 31 deletions(-)

    Reviewed-by: Song Gao <gaos...@loongson.cn>
    Tested-by: Song Gao <gaos...@loongson.cn>


Thanks.
Song Gao

diff --git a/target/loongarch/tcg/tlb_helper.c 
b/target/loongarch/tcg/tlb_helper.c
index 8872593ff0..3ea0e153b1 100644
--- a/target/loongarch/tcg/tlb_helper.c
+++ b/target/loongarch/tcg/tlb_helper.c
@@ -110,11 +110,8 @@ static void invalidate_tlb_entry(CPULoongArchState *env, 
int index)
      if (!tlb_e) {
          return;
      }
-    if (index >= LOONGARCH_STLB) {
-        tlb_ps = FIELD_EX64(tlb->tlb_misc, TLB_MISC, PS);
-    } else {
-        tlb_ps = FIELD_EX64(env->CSR_STLBPS, CSR_STLBPS, PS);
-    }
+
+    tlb_ps = FIELD_EX64(tlb->tlb_misc, TLB_MISC, PS);
      pagesize = MAKE_64BIT_MASK(tlb_ps, 1);
      mask = MAKE_64BIT_MASK(0, tlb_ps + 1);

@@ -173,11 +170,8 @@ static void fill_tlb_entry(CPULoongArchState *env, int index)

          lo1 = env->CSR_TLBELO1;
      }

- /* Only MTLB has the ps fields */

-    if (index >= LOONGARCH_STLB) {
-        tlb->tlb_misc = FIELD_DP64(tlb->tlb_misc, TLB_MISC, PS, csr_ps);
-    }
-
+    /* Store page size in field PS */
+    tlb->tlb_misc = FIELD_DP64(tlb->tlb_misc, TLB_MISC, PS, csr_ps);
      tlb->tlb_misc = FIELD_DP64(tlb->tlb_misc, TLB_MISC, VPPN, csr_vppn);
      tlb->tlb_misc = FIELD_DP64(tlb->tlb_misc, TLB_MISC, E, 1);
      csr_asid = FIELD_EX64(env->CSR_ASID, CSR_ASID, ASID);
@@ -283,12 +277,7 @@ void helper_tlbrd(CPULoongArchState *env)

index = FIELD_EX64(env->CSR_TLBIDX, CSR_TLBIDX, INDEX);

      tlb = &env->tlb[index];
-
-    if (index >= LOONGARCH_STLB) {
-        tlb_ps = FIELD_EX64(tlb->tlb_misc, TLB_MISC, PS);
-    } else {
-        tlb_ps = FIELD_EX64(env->CSR_STLBPS, CSR_STLBPS, PS);
-    }
+    tlb_ps = FIELD_EX64(tlb->tlb_misc, TLB_MISC, PS);
      tlb_e = FIELD_EX64(tlb->tlb_misc, TLB_MISC, E);

if (!tlb_e) {

@@ -476,11 +465,8 @@ void helper_invtlb_page_asid(CPULoongArchState *env, 
target_ulong info,
          if (!tlb_e) {
              continue;
          }
-        if (i >= LOONGARCH_STLB) {
-            tlb_ps = FIELD_EX64(tlb->tlb_misc, TLB_MISC, PS);
-        } else {
-            tlb_ps = FIELD_EX64(env->CSR_STLBPS, CSR_STLBPS, PS);
-        }
+
+        tlb_ps = FIELD_EX64(tlb->tlb_misc, TLB_MISC, PS);
          tlb_vppn = FIELD_EX64(tlb->tlb_misc, TLB_MISC, VPPN);
          vpn = (addr & TARGET_VIRT_MASK) >> (tlb_ps + 1);
          compare_shift = tlb_ps + 1 - R_TLB_MISC_VPPN_SHIFT;
@@ -509,11 +495,8 @@ void helper_invtlb_page_asid_or_g(CPULoongArchState *env,
          if (!tlb_e) {
              continue;
          }
-        if (i >= LOONGARCH_STLB) {
-            tlb_ps = FIELD_EX64(tlb->tlb_misc, TLB_MISC, PS);
-        } else {
-            tlb_ps = FIELD_EX64(env->CSR_STLBPS, CSR_STLBPS, PS);
-        }
+
+        tlb_ps = FIELD_EX64(tlb->tlb_misc, TLB_MISC, PS);
          tlb_vppn = FIELD_EX64(tlb->tlb_misc, TLB_MISC, VPPN);
          vpn = (addr & TARGET_VIRT_MASK) >> (tlb_ps + 1);
          compare_shift = tlb_ps + 1 - R_TLB_MISC_VPPN_SHIFT;
@@ -673,11 +656,7 @@ static int loongarch_map_tlb_entry(CPULoongArchState *env, 
hwaddr *physical,
      uint64_t tlb_entry, tlb_ppn;
      uint8_t tlb_ps, n, tlb_v, tlb_d, tlb_plv, tlb_nx, tlb_nr, tlb_rplv;

- if (index >= LOONGARCH_STLB) {

-        tlb_ps = FIELD_EX64(tlb->tlb_misc, TLB_MISC, PS);
-    } else {
-        tlb_ps = FIELD_EX64(env->CSR_STLBPS, CSR_STLBPS, PS);
-    }
+    tlb_ps = FIELD_EX64(tlb->tlb_misc, TLB_MISC, PS);
      n = (address >> tlb_ps) & 0x1;/* Odd or even */

tlb_entry = n ? tlb->tlb_entry1 : tlb->tlb_entry0;