[03/27] target/riscv: cpu: store max SATP mode as a single integer

Commit Message

Paolo Bonzini April 6, 2025, 7:02 a.m. UTC

The maximum available SATP mode implies all the shorter virtual address sizes.
Store it in RISCVCPUConfig and avoid recomputing it via satp_mode_max_from_map.

Reviewed-by: Alistair Francis <[e-mail]>
Signed-off-by: Paolo Bonzini <[e-mail]>
---
 target/riscv/cpu_cfg.h     |  1 +
 target/riscv/cpu.c         | 14 ++++++++------
 target/riscv/tcg/tcg-cpu.c |  3 ++-
 3 files changed, 11 insertions(+), 7 deletions(-)

Patch

diff --git a/target/riscv/cpu_cfg.h b/target/riscv/cpu_cfg.h
index 8a843482cc6..1678a16accb 100644
--- a/target/riscv/cpu_cfg.h
+++ b/target/riscv/cpu_cfg.h
@@ -197,6 +197,7 @@  struct RISCVCPUConfig {
     bool short_isa_string;
 
 #ifndef CONFIG_USER_ONLY
+    int8_t max_satp_mode;
     RISCVSATPMap satp_mode;
 #endif
 };
diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
index fffd263a799..4dcab156948 100644
--- a/target/riscv/cpu.c
+++ b/target/riscv/cpu.c
@@ -447,6 +447,7 @@  static void set_satp_mode_max_supported(RISCVCPU *cpu,
     }
 
     assert(cpu->cfg.satp_mode.supported & (1 << satp_mode));
+    cpu->cfg.max_satp_mode = satp_mode;
 }
 
 /* Set the satp mode to the max supported */
@@ -1180,16 +1181,13 @@  static void riscv_cpu_disas_set_info(CPUState *s, disassemble_info *info)
 static void riscv_cpu_satp_mode_finalize(RISCVCPU *cpu, Error **errp)
 {
     bool rv32 = riscv_cpu_is_32bit(cpu);
-    uint8_t satp_mode_map_max, satp_mode_supported_max;
+    uint8_t satp_mode_map_max;
 
     /* The CPU wants the OS to decide which satp mode to use */
     if (cpu->cfg.satp_mode.supported == 0) {
         return;
     }
 
-    satp_mode_supported_max =
-                    satp_mode_max_from_map(cpu->cfg.satp_mode.supported);
-
     if (cpu->cfg.satp_mode.map == 0) {
         if (cpu->cfg.satp_mode.init == 0) {
             /* If unset by the user, we fallback to the default satp mode. */
@@ -1218,10 +1216,10 @@  static void riscv_cpu_satp_mode_finalize(RISCVCPU *cpu, Error **errp)
     satp_mode_map_max = satp_mode_max_from_map(cpu->cfg.satp_mode.map);
 
     /* Make sure the user asked for a supported configuration (HW and qemu) */
-    if (satp_mode_map_max > satp_mode_supported_max) {
+    if (satp_mode_map_max > cpu->cfg.max_satp_mode) {
         error_setg(errp, "satp_mode %s is higher than hw max capability %s",
                    satp_mode_str(satp_mode_map_max, rv32),
-                   satp_mode_str(satp_mode_supported_max, rv32));
+                   satp_mode_str(cpu->cfg.max_satp_mode, rv32));
         return;
     }
 
@@ -1481,6 +1479,10 @@  static void riscv_cpu_init(Object *obj)
     cpu->cfg.cbop_blocksize = 64;
     cpu->cfg.cboz_blocksize = 64;
     cpu->env.vext_ver = VEXT_VERSION_1_00_0;
+
+#ifndef CONFIG_USER_ONLY
+    cpu->cfg.max_satp_mode = -1;
+#endif /* CONFIG_USER_ONLY */
 }
 
 static void riscv_bare_cpu_init(Object *obj)
diff --git a/target/riscv/tcg/tcg-cpu.c b/target/riscv/tcg/tcg-cpu.c
index 5aef9eef366..2f93e2dd285 100644
--- a/target/riscv/tcg/tcg-cpu.c
+++ b/target/riscv/tcg/tcg-cpu.c
@@ -706,8 +706,9 @@  static bool riscv_cpu_validate_profile_satp(RISCVCPU *cpu,
                                             RISCVCPUProfile *profile,
                                             bool send_warn)
 {
-    int satp_max = satp_mode_max_from_map(cpu->cfg.satp_mode.supported);
+    int satp_max = cpu->cfg.max_satp_mode;
 
+    assert(satp_max >= 0);
     if (profile->satp_mode > satp_max) {
         if (send_warn) {
             bool is_32bit = riscv_cpu_is_32bit(cpu);