diff mbox series

[RFC,v2,1/3] hw/intc: Add .impl.[min|max]_access_size declaration in RISC-V ACLINT

Message ID 20220210061737.1171-2-frank.chang@sifive.com
State New
Headers show
Series Support ACLINT 32/64-bit mtimecmp/mtime read/write accesses | expand

Commit Message

Frank Chang Feb. 10, 2022, 6:17 a.m. UTC 
From: Frank Chang <frank.chang@sifive.com>

If device's MemoryRegion doesn't have .impl.[min|max]_access_size
declaration, the default access_size_min would be 1 byte and
access_size_max would be 4 bytes (see: softmmu/memory.c).
This will cause a 64-bit memory access to ACLINT to be splitted into
two 32-bit memory accesses.

Signed-off-by: Frank Chang <frank.chang@sifive.com>
---
 hw/intc/riscv_aclint.c | 4 ++++
 1 file changed, 4 insertions(+)

Comments

Alistair Francis Feb. 21, 2022, 9:47 p.m. UTC | #1 
On Thu, Feb 10, 2022 at 4:19 PM <frank.chang@sifive.com> wrote:
>
> From: Frank Chang <frank.chang@sifive.com>
>
> If device's MemoryRegion doesn't have .impl.[min|max]_access_size
> declaration, the default access_size_min would be 1 byte and
> access_size_max would be 4 bytes (see: softmmu/memory.c).
> This will cause a 64-bit memory access to ACLINT to be splitted into
> two 32-bit memory accesses.
>
> Signed-off-by: Frank Chang <frank.chang@sifive.com>

Reviewed-by: Alistair Francis <alistair.francis@wdc.com>

Alistair

> ---
>  hw/intc/riscv_aclint.c | 4 ++++
>  1 file changed, 4 insertions(+)
>
> diff --git a/hw/intc/riscv_aclint.c b/hw/intc/riscv_aclint.c
> index f1a5d3d284..3b598d8a7e 100644
> --- a/hw/intc/riscv_aclint.c
> +++ b/hw/intc/riscv_aclint.c
> @@ -208,6 +208,10 @@ static const MemoryRegionOps riscv_aclint_mtimer_ops = {
>      .valid = {
>          .min_access_size = 4,
>          .max_access_size = 8
> +    },
> +    .impl = {
> +        .min_access_size = 4,
> +        .max_access_size = 8,
>      }
>  };
>
> --
> 2.31.1
>
>
diff mbox series

Patch

diff --git a/hw/intc/riscv_aclint.c b/hw/intc/riscv_aclint.c
index f1a5d3d284..3b598d8a7e 100644
--- a/hw/intc/riscv_aclint.c
+++ b/hw/intc/riscv_aclint.c
@@ -208,6 +208,10 @@  static const MemoryRegionOps riscv_aclint_mtimer_ops = {
     .valid = {
         .min_access_size = 4,
         .max_access_size = 8
+    },
+    .impl = {
+        .min_access_size = 4,
+        .max_access_size = 8,
     }
 };