diff mbox series

target/riscv/cpu.c: fix veyron-v1 CPU properties

Message ID 20230620152443.137079-1-dbarboza@ventanamicro.com
State New
Headers show
Series target/riscv/cpu.c: fix veyron-v1 CPU properties | expand

Commit Message

Daniel Henrique Barboza June 20, 2023, 3:24 p.m. UTC
Commit 7f0bdfb5bfc2 ("target/riscv/cpu.c: remove cfg setup from
riscv_cpu_init()") removed code that was enabling mmu, pmp, ext_ifencei
and ext_icsr from riscv_cpu_init(), the init() function of
TYPE_RISCV_CPU, parent type of all RISC-V CPUss. This was done to force
CPUs to explictly enable all extensions and features it requires,
without any 'magic values' that were inherited by the parent type.

This commit failed to make appropriate changes in the 'veyron-v1' CPU,
added earlier by commit e1d084a8524a. The result is that the veyron-v1
CPU has ext_ifencei, ext_icsr and pmp set to 'false', which is not the
case.

The reason why it took this long to notice (thanks LIU Zhiwei for
reporting it) is because Linux doesn't mind 'ifencei' and 'icsr' being
absent in the 'riscv,isa' DT, implying that they're both present if the
'i' extension is enabled. OpenSBI also doesn't error out or warns about
the lack of 'pmp', it'll just not protect memory pages.

Fix it by setting them to 'true' in rv64_veyron_v1_cpu_init() like
7f0bdfb5bfc2 already did with other CPUs.

Reported-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Fixes: 7f0bdfb5bfc2 ("target/riscv/cpu.c: remove cfg setup from riscv_cpu_init()")
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
---
 target/riscv/cpu.c | 3 +++
 1 file changed, 3 insertions(+)

Comments

Alistair Francis June 21, 2023, 12:24 a.m. UTC | #1
On Wed, Jun 21, 2023 at 1:25 AM Daniel Henrique Barboza
<dbarboza@ventanamicro.com> wrote:
>
> Commit 7f0bdfb5bfc2 ("target/riscv/cpu.c: remove cfg setup from
> riscv_cpu_init()") removed code that was enabling mmu, pmp, ext_ifencei
> and ext_icsr from riscv_cpu_init(), the init() function of
> TYPE_RISCV_CPU, parent type of all RISC-V CPUss. This was done to force
> CPUs to explictly enable all extensions and features it requires,
> without any 'magic values' that were inherited by the parent type.
>
> This commit failed to make appropriate changes in the 'veyron-v1' CPU,
> added earlier by commit e1d084a8524a. The result is that the veyron-v1
> CPU has ext_ifencei, ext_icsr and pmp set to 'false', which is not the
> case.
>
> The reason why it took this long to notice (thanks LIU Zhiwei for
> reporting it) is because Linux doesn't mind 'ifencei' and 'icsr' being
> absent in the 'riscv,isa' DT, implying that they're both present if the
> 'i' extension is enabled. OpenSBI also doesn't error out or warns about
> the lack of 'pmp', it'll just not protect memory pages.
>
> Fix it by setting them to 'true' in rv64_veyron_v1_cpu_init() like
> 7f0bdfb5bfc2 already did with other CPUs.
>
> Reported-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
> Fixes: 7f0bdfb5bfc2 ("target/riscv/cpu.c: remove cfg setup from riscv_cpu_init()")
> Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>

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

Alistair

> ---
>  target/riscv/cpu.c | 3 +++
>  1 file changed, 3 insertions(+)
>
> diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
> index 881bddf393..707f62b592 100644
> --- a/target/riscv/cpu.c
> +++ b/target/riscv/cpu.c
> @@ -444,6 +444,9 @@ static void rv64_veyron_v1_cpu_init(Object *obj)
>
>      /* Enable ISA extensions */
>      cpu->cfg.mmu = true;
> +    cpu->cfg.ext_ifencei = true;
> +    cpu->cfg.ext_icsr = true;
> +    cpu->cfg.pmp = true;
>      cpu->cfg.ext_icbom = true;
>      cpu->cfg.cbom_blocksize = 64;
>      cpu->cfg.cboz_blocksize = 64;
> --
> 2.41.0
>
>
LIU Zhiwei June 21, 2023, 1:32 a.m. UTC | #2
On 2023/6/20 23:24, Daniel Henrique Barboza wrote:
> Commit 7f0bdfb5bfc2 ("target/riscv/cpu.c: remove cfg setup from
> riscv_cpu_init()") removed code that was enabling mmu, pmp, ext_ifencei
> and ext_icsr from riscv_cpu_init(), the init() function of
> TYPE_RISCV_CPU, parent type of all RISC-V CPUss. This was done to force
> CPUs to explictly enable all extensions and features it requires,
> without any 'magic values' that were inherited by the parent type.
>
> This commit failed to make appropriate changes in the 'veyron-v1' CPU,
> added earlier by commit e1d084a8524a. The result is that the veyron-v1
> CPU has ext_ifencei, ext_icsr and pmp set to 'false', which is not the
> case.
>
> The reason why it took this long to notice (thanks LIU Zhiwei for
> reporting it) is because Linux doesn't mind 'ifencei' and 'icsr' being
> absent in the 'riscv,isa' DT, implying that they're both present if the
> 'i' extension is enabled. OpenSBI also doesn't error out or warns about
> the lack of 'pmp', it'll just not protect memory pages.
>
> Fix it by setting them to 'true' in rv64_veyron_v1_cpu_init() like
> 7f0bdfb5bfc2 already did with other CPUs.
>
> Reported-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
> Fixes: 7f0bdfb5bfc2 ("target/riscv/cpu.c: remove cfg setup from riscv_cpu_init()")
> Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
> ---
>   target/riscv/cpu.c | 3 +++
>   1 file changed, 3 insertions(+)
>
> diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
> index 881bddf393..707f62b592 100644
> --- a/target/riscv/cpu.c
> +++ b/target/riscv/cpu.c
> @@ -444,6 +444,9 @@ static void rv64_veyron_v1_cpu_init(Object *obj)
>   
>       /* Enable ISA extensions */
>       cpu->cfg.mmu = true;
> +    cpu->cfg.ext_ifencei = true;
> +    cpu->cfg.ext_icsr = true;
> +    cpu->cfg.pmp = true;

Reviewed-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>

Zhiwei

>       cpu->cfg.ext_icbom = true;
>       cpu->cfg.cbom_blocksize = 64;
>       cpu->cfg.cboz_blocksize = 64;
Alistair Francis June 22, 2023, 2:30 a.m. UTC | #3
On Wed, Jun 21, 2023 at 1:25 AM Daniel Henrique Barboza
<dbarboza@ventanamicro.com> wrote:
>
> Commit 7f0bdfb5bfc2 ("target/riscv/cpu.c: remove cfg setup from
> riscv_cpu_init()") removed code that was enabling mmu, pmp, ext_ifencei
> and ext_icsr from riscv_cpu_init(), the init() function of
> TYPE_RISCV_CPU, parent type of all RISC-V CPUss. This was done to force
> CPUs to explictly enable all extensions and features it requires,
> without any 'magic values' that were inherited by the parent type.
>
> This commit failed to make appropriate changes in the 'veyron-v1' CPU,
> added earlier by commit e1d084a8524a. The result is that the veyron-v1
> CPU has ext_ifencei, ext_icsr and pmp set to 'false', which is not the
> case.
>
> The reason why it took this long to notice (thanks LIU Zhiwei for
> reporting it) is because Linux doesn't mind 'ifencei' and 'icsr' being
> absent in the 'riscv,isa' DT, implying that they're both present if the
> 'i' extension is enabled. OpenSBI also doesn't error out or warns about
> the lack of 'pmp', it'll just not protect memory pages.
>
> Fix it by setting them to 'true' in rv64_veyron_v1_cpu_init() like
> 7f0bdfb5bfc2 already did with other CPUs.
>
> Reported-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
> Fixes: 7f0bdfb5bfc2 ("target/riscv/cpu.c: remove cfg setup from riscv_cpu_init()")
> Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>

Thanks!

Applied to riscv-to-apply.next

Alistair

> ---
>  target/riscv/cpu.c | 3 +++
>  1 file changed, 3 insertions(+)
>
> diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
> index 881bddf393..707f62b592 100644
> --- a/target/riscv/cpu.c
> +++ b/target/riscv/cpu.c
> @@ -444,6 +444,9 @@ static void rv64_veyron_v1_cpu_init(Object *obj)
>
>      /* Enable ISA extensions */
>      cpu->cfg.mmu = true;
> +    cpu->cfg.ext_ifencei = true;
> +    cpu->cfg.ext_icsr = true;
> +    cpu->cfg.pmp = true;
>      cpu->cfg.ext_icbom = true;
>      cpu->cfg.cbom_blocksize = 64;
>      cpu->cfg.cboz_blocksize = 64;
> --
> 2.41.0
>
>
diff mbox series

Patch

diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
index 881bddf393..707f62b592 100644
--- a/target/riscv/cpu.c
+++ b/target/riscv/cpu.c
@@ -444,6 +444,9 @@  static void rv64_veyron_v1_cpu_init(Object *obj)
 
     /* Enable ISA extensions */
     cpu->cfg.mmu = true;
+    cpu->cfg.ext_ifencei = true;
+    cpu->cfg.ext_icsr = true;
+    cpu->cfg.pmp = true;
     cpu->cfg.ext_icbom = true;
     cpu->cfg.cbom_blocksize = 64;
     cpu->cfg.cboz_blocksize = 64;