target/loongarch: Set unused flag with CSR registers

On LA464, some CSR registers are not used such as CSR_SAVE8 -
CSR_SAVE15, also CSR registers relative with MCE is not used now.

Flag CSRFL_UNUSED is added for these registers, so that it will
not dumped. In order to keep compatiblity, these CSR registers are
not removed since it is used in vmstate already.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>

diff --git a/target/loongarch/cpu.c b/target/loongarch/cpu.c
index d611a6047042e5f9d3797e0bc3f3e868c78502ca..a74401033213d4d1b64471c3bfa4009bbb9f6f8b 100644 (file)
--- a/target/loongarch/cpu.c
+++ b/target/loongarch/cpu.c
@@ -19,7 +19,7 @@
 #include "cpu.h"
 #include "internals.h"
 #include "fpu/softfloat-helpers.h"
-#include "cpu-csr.h"
+#include "csr.h"
 #ifndef CONFIG_USER_ONLY
 #include "system/reset.h"
 #endif
@@ -375,6 +375,33 @@ static int loongarch_cpu_mmu_index(CPUState *cs, bool ifetch)
     return MMU_DA_IDX;
 }
 
+static void loongarch_la464_init_csr(Object *obj)
+{
+#ifndef CONFIG_USER_ONLY
+    static bool initialized;
+    LoongArchCPU *cpu = LOONGARCH_CPU(obj);
+    CPULoongArchState *env = &cpu->env;
+    int i, num;
+
+    if (!initialized) {
+        initialized = true;
+        num = FIELD_EX64(env->CSR_PRCFG1, CSR_PRCFG1, SAVE_NUM);
+        for (i = num; i < 16; i++) {
+            set_csr_flag(LOONGARCH_CSR_SAVE(i), CSRFL_UNUSED);
+        }
+        set_csr_flag(LOONGARCH_CSR_IMPCTL1, CSRFL_UNUSED);
+        set_csr_flag(LOONGARCH_CSR_IMPCTL2, CSRFL_UNUSED);
+        set_csr_flag(LOONGARCH_CSR_MERRCTL, CSRFL_UNUSED);
+        set_csr_flag(LOONGARCH_CSR_MERRINFO1, CSRFL_UNUSED);
+        set_csr_flag(LOONGARCH_CSR_MERRINFO2, CSRFL_UNUSED);
+        set_csr_flag(LOONGARCH_CSR_MERRENTRY, CSRFL_UNUSED);
+        set_csr_flag(LOONGARCH_CSR_MERRERA, CSRFL_UNUSED);
+        set_csr_flag(LOONGARCH_CSR_MERRSAVE, CSRFL_UNUSED);
+        set_csr_flag(LOONGARCH_CSR_CTAG, CSRFL_UNUSED);
+    }
+#endif
+}
+
 static void loongarch_la464_initfn(Object *obj)
 {
     LoongArchCPU *cpu = LOONGARCH_CPU(obj);
@@ -470,6 +497,7 @@ static void loongarch_la464_initfn(Object *obj)
     env->CSR_PRCFG3 = FIELD_DP64(env->CSR_PRCFG3, CSR_PRCFG3, STLB_WAYS, 7);
     env->CSR_PRCFG3 = FIELD_DP64(env->CSR_PRCFG3, CSR_PRCFG3, STLB_SETS, 8);
 
+    loongarch_la464_init_csr(obj);
     loongarch_cpu_post_init(obj);
 }
 

diff --git a/target/loongarch/csr.c b/target/loongarch/csr.c
index 62c1815bfb43dec7c7c2d757f1f7d97fc8ad79fb..87bd24e8cd6bb4bbe23a89d1ec8663f02b5c95b1 100644 (file)
--- a/target/loongarch/csr.c
+++ b/target/loongarch/csr.c
@@ -112,3 +112,16 @@ CSRInfo *get_csr(unsigned int csr_num)
 
     return csr;
 }
+
+bool set_csr_flag(unsigned int csr_num, int flag)
+{
+    CSRInfo *csr;
+
+    csr = get_csr(csr_num);
+    if (!csr) {
+        return false;
+    }
+
+    csr->flags |= flag;
+    return true;
+}

diff --git a/target/loongarch/csr.h b/target/loongarch/csr.h
index caad83254573a92784b25f145df7d7cd95e5442d..deb1aacc3362f7327ba5d9a86cbd3c4fdd56bc38 100644 (file)
--- a/target/loongarch/csr.h
+++ b/target/loongarch/csr.h
@@ -13,6 +13,7 @@ enum {
     CSRFL_READONLY = (1 << 0),
     CSRFL_EXITTB   = (1 << 1),
     CSRFL_IO       = (1 << 2),
+    CSRFL_UNUSED   = (1 << 3),
 };
 
 typedef struct {
@@ -23,4 +24,5 @@ typedef struct {
 } CSRInfo;
 
 CSRInfo *get_csr(unsigned int csr_num);
+bool set_csr_flag(unsigned int csr_num, int flag);
 #endif /* TARGET_LOONGARCH_CSR_H */