[v2,10/11] target/riscv: remove RISCV_FEATURE_MMU

Commit Message

Daniel Henrique Barboza Feb. 14, 2023, 7:23 p.m. UTC

RISCV_FEATURE_MMU is set whether cpu->cfg.mmu is set, so let's just use
the flag directly instead.

With this change the enum is also removed. It is worth noticing that
this enum, and all the RISCV_FEATURES_* that were contained in it,
predates the existence of the cpu->cfg object. Today, using cpu->cfg is
an easier way to retrieve all the features and extensions enabled in the
hart.

Reviewed-by: Weiwei Li <[e-mail]>
Signed-off-by: Daniel Henrique Barboza <[e-mail]>
---
 target/riscv/cpu.c        | 4 ----
 target/riscv/cpu.h        | 7 -------
 target/riscv/cpu_helper.c | 2 +-
 target/riscv/csr.c        | 4 ++--
 target/riscv/monitor.c    | 2 +-
 target/riscv/pmp.c        | 2 +-
 6 files changed, 5 insertions(+), 16 deletions(-)

Comments

Bin Meng Feb. 15, 2023, 11:22 a.m. UTC | #1

On Wed, Feb 15, 2023 at 3:27 AM Daniel Henrique Barboza
<[e-mail]> wrote:
>
> RISCV_FEATURE_MMU is set whether cpu->cfg.mmu is set, so let's just use
> the flag directly instead.
>
> With this change the enum is also removed. It is worth noticing that
> this enum, and all the RISCV_FEATURES_* that were contained in it,
> predates the existence of the cpu->cfg object. Today, using cpu->cfg is
> an easier way to retrieve all the features and extensions enabled in the
> hart.
>
> Reviewed-by: Weiwei Li <[e-mail]>
> Signed-off-by: Daniel Henrique Barboza <[e-mail]>
> ---
>  target/riscv/cpu.c        | 4 ----
>  target/riscv/cpu.h        | 7 -------
>  target/riscv/cpu_helper.c | 2 +-
>  target/riscv/csr.c        | 4 ++--
>  target/riscv/monitor.c    | 2 +-
>  target/riscv/pmp.c        | 2 +-
>  6 files changed, 5 insertions(+), 16 deletions(-)
>

Reviewed-by: Bin Meng <[e-mail]>

Patch

diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
index a803395ed1..2859ebc3e6 100644
--- a/target/riscv/cpu.c
+++ b/target/riscv/cpu.c
@@ -919,10 +919,6 @@  static void riscv_cpu_realize(DeviceState *dev, Error **errp)
         }
     }
 
-    if (cpu->cfg.mmu) {
-        riscv_set_feature(env, RISCV_FEATURE_MMU);
-    }
-
     if (cpu->cfg.epmp && !cpu->cfg.pmp) {
         /*
          * Enhanced PMP should only be available
diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h
index 62919cd5cc..83a9fa38d9 100644
--- a/target/riscv/cpu.h
+++ b/target/riscv/cpu.h
@@ -81,13 +81,6 @@ 
 #define RVH RV('H')
 #define RVJ RV('J')
 
-/* S extension denotes that Supervisor mode exists, however it is possible
-   to have a core that support S mode but does not have an MMU and there
-   is currently no bit in misa to indicate whether an MMU exists or not
-   so a cpu features bitfield is required, likewise for optional PMP support */
-enum {
-    RISCV_FEATURE_MMU,
-};
 
 /* Privileged specification version */
 enum {
diff --git a/target/riscv/cpu_helper.c b/target/riscv/cpu_helper.c
index 15d9542691..e76b206191 100644
--- a/target/riscv/cpu_helper.c
+++ b/target/riscv/cpu_helper.c
@@ -796,7 +796,7 @@  static int get_physical_address(CPURISCVState *env, hwaddr *physical,
         mode = PRV_U;
     }
 
-    if (mode == PRV_M || !riscv_feature(env, RISCV_FEATURE_MMU)) {
+    if (mode == PRV_M || !riscv_cpu_cfg(env).mmu) {
         *physical = addr;
         *prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC;
         return TRANSLATE_SUCCESS;
diff --git a/target/riscv/csr.c b/target/riscv/csr.c
index 356cf3c04f..54bcdbc4dc 100644
--- a/target/riscv/csr.c
+++ b/target/riscv/csr.c
@@ -2621,7 +2621,7 @@  static RISCVException rmw_siph(CPURISCVState *env, int csrno,
 static RISCVException read_satp(CPURISCVState *env, int csrno,
                                 target_ulong *val)
 {
-    if (!riscv_feature(env, RISCV_FEATURE_MMU)) {
+    if (!riscv_cpu_cfg(env).mmu) {
         *val = 0;
         return RISCV_EXCP_NONE;
     }
@@ -2640,7 +2640,7 @@  static RISCVException write_satp(CPURISCVState *env, int csrno,
 {
     target_ulong vm, mask;
 
-    if (!riscv_feature(env, RISCV_FEATURE_MMU)) {
+    if (!riscv_cpu_cfg(env).mmu) {
         return RISCV_EXCP_NONE;
     }
 
diff --git a/target/riscv/monitor.c b/target/riscv/monitor.c
index 236f93b9f5..b7b8d0614f 100644
--- a/target/riscv/monitor.c
+++ b/target/riscv/monitor.c
@@ -218,7 +218,7 @@  void hmp_info_mem(Monitor *mon, const QDict *qdict)
         return;
     }
 
-    if (!riscv_feature(env, RISCV_FEATURE_MMU)) {
+    if (!riscv_cpu_cfg(env).mmu) {
         monitor_printf(mon, "S-mode MMU unavailable\n");
         return;
     }
diff --git a/target/riscv/pmp.c b/target/riscv/pmp.c
index 1e7903dffa..c67de36942 100644
--- a/target/riscv/pmp.c
+++ b/target/riscv/pmp.c
@@ -315,7 +315,7 @@  int pmp_hart_has_privs(CPURISCVState *env, target_ulong addr,
     }
 
     if (size == 0) {
-        if (riscv_feature(env, RISCV_FEATURE_MMU)) {
+        if (riscv_cpu_cfg(env).mmu) {
             /*
              * If size is unknown (0), assume that all bytes
              * from addr to the end of the page will be accessed.