diff mbox series

[v2,05/12] target/arm: Cache the GP bit for a page in MemTxAttrs

Message ID 20190128223118.5255-6-richard.henderson@linaro.org
State Superseded
Headers show
Series target/arm: Implement ARMv8.5-BTI | expand

Commit Message

Richard Henderson Jan. 28, 2019, 10:31 p.m. UTC
Caching the bit means that we will not have to re-walk the
page tables to look up the bit during translation.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

---
 target/arm/helper.c | 6 ++++++
 1 file changed, 6 insertions(+)

-- 
2.17.2

Comments

Peter Maydell Feb. 4, 2019, 11:41 a.m. UTC | #1
On Mon, 28 Jan 2019 at 22:31, Richard Henderson
<richard.henderson@linaro.org> wrote:
>

> Caching the bit means that we will not have to re-walk the

> page tables to look up the bit during translation.

>

> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

> ---

>  target/arm/helper.c | 6 ++++++

>  1 file changed, 6 insertions(+)

>

> diff --git a/target/arm/helper.c b/target/arm/helper.c

> index 6efe88a157..70277222da 100644

> --- a/target/arm/helper.c

> +++ b/target/arm/helper.c

> @@ -10457,6 +10457,7 @@ static bool get_phys_addr_lpae(CPUARMState *env, target_ulong address,

>      bool ttbr1_valid;

>      uint64_t descaddrmask;

>      bool aarch64 = arm_el_is_aa64(env, el);

> +    bool guarded = false;

>

>      /* TODO:

>       * This code does not handle the different format TCR for VTCR_EL2.

> @@ -10629,6 +10630,7 @@ static bool get_phys_addr_lpae(CPUARMState *env, target_ulong address,

>          }

>          /* Merge in attributes from table descriptors */

>          attrs |= nstable << 3; /* NS */

> +        guarded |= extract64(descriptor, 50, 1);  /* GP */


Should just be "guarded =", as per previous discussion.
Otherwise
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>


thanks
-- PMM
Richard Henderson Feb. 4, 2019, 11:58 a.m. UTC | #2
On 2/4/19 11:41 AM, Peter Maydell wrote:
> On Mon, 28 Jan 2019 at 22:31, Richard Henderson

> <richard.henderson@linaro.org> wrote:

>>

>> Caching the bit means that we will not have to re-walk the

>> page tables to look up the bit during translation.

>>

>> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

>> ---

>>  target/arm/helper.c | 6 ++++++

>>  1 file changed, 6 insertions(+)

>>

>> diff --git a/target/arm/helper.c b/target/arm/helper.c

>> index 6efe88a157..70277222da 100644

>> --- a/target/arm/helper.c

>> +++ b/target/arm/helper.c

>> @@ -10457,6 +10457,7 @@ static bool get_phys_addr_lpae(CPUARMState *env, target_ulong address,

>>      bool ttbr1_valid;

>>      uint64_t descaddrmask;

>>      bool aarch64 = arm_el_is_aa64(env, el);

>> +    bool guarded = false;

>>

>>      /* TODO:

>>       * This code does not handle the different format TCR for VTCR_EL2.

>> @@ -10629,6 +10630,7 @@ static bool get_phys_addr_lpae(CPUARMState *env, target_ulong address,

>>          }

>>          /* Merge in attributes from table descriptors */

>>          attrs |= nstable << 3; /* NS */

>> +        guarded |= extract64(descriptor, 50, 1);  /* GP */

> 

> Should just be "guarded =", as per previous discussion.

> Otherwise

> Reviewed-by: Peter Maydell <peter.maydell@linaro.org>


Agreed.  Do you need a re-spin for this?


r~
diff mbox series

Patch

diff --git a/target/arm/helper.c b/target/arm/helper.c
index 6efe88a157..70277222da 100644
--- a/target/arm/helper.c
+++ b/target/arm/helper.c
@@ -10457,6 +10457,7 @@  static bool get_phys_addr_lpae(CPUARMState *env, target_ulong address,
     bool ttbr1_valid;
     uint64_t descaddrmask;
     bool aarch64 = arm_el_is_aa64(env, el);
+    bool guarded = false;
 
     /* TODO:
      * This code does not handle the different format TCR for VTCR_EL2.
@@ -10629,6 +10630,7 @@  static bool get_phys_addr_lpae(CPUARMState *env, target_ulong address,
         }
         /* Merge in attributes from table descriptors */
         attrs |= nstable << 3; /* NS */
+        guarded |= extract64(descriptor, 50, 1);  /* GP */
         if (param.hpd) {
             /* HPD disables all the table attributes except NSTable.  */
             break;
@@ -10674,6 +10676,10 @@  static bool get_phys_addr_lpae(CPUARMState *env, target_ulong address,
          */
         txattrs->secure = false;
     }
+    /* When in aarch64 mode, and BTI is enabled, remember GP in the IOTLB.  */
+    if (aarch64 && guarded && cpu_isar_feature(aa64_bti, cpu)) {
+        txattrs->target_tlb_bit0 = true;
+    }
 
     if (cacheattrs != NULL) {
         if (mmu_idx == ARMMMUIdx_S2NS) {