[PATCH v2] drm/etnaviv: fix external abort seen on GC600 rev 0x19

[PATCH v2] drm/etnaviv: fix external abort seen on GC600 rev 0x19

[Christian Gmeiner]

It looks like that this GPU core triggers an abort when
reading VIVS_HI_CHIP_PRODUCT_ID and/or VIVS_HI_CHIP_ECO_ID.

I looked at different versions of Vivante's kernel driver and did
not found anything about this issue or what feature flag can be
used. So go the simplest route and do not read these two registers
on the affected GPU core.

Signed-off-by: Christian Gmeiner <christian.gmeiner@gmail.com>
Reported-by: Josua Mayer <josua.mayer@jm0.eu>
Fixes: 815e45bbd4d3 ("drm/etnaviv: determine product, customer and eco id")
Cc: stable@vger.kernel.org
---
Changelog:

V2:
 - use correct register for conditional reads.

---
 drivers/gpu/drm/etnaviv/etnaviv_gpu.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
index d5a4cd85a0f6..c6404b8d067f 100644
--- a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
@@ -337,9 +337,16 @@ static void etnaviv_hw_identify(struct etnaviv_gpu *gpu)
 
 		gpu->identity.model = gpu_read(gpu, VIVS_HI_CHIP_MODEL);
 		gpu->identity.revision = gpu_read(gpu, VIVS_HI_CHIP_REV);
-		gpu->identity.product_id = gpu_read(gpu, VIVS_HI_CHIP_PRODUCT_ID);
 		gpu->identity.customer_id = gpu_read(gpu, VIVS_HI_CHIP_CUSTOMER_ID);
-		gpu->identity.eco_id = gpu_read(gpu, VIVS_HI_CHIP_ECO_ID);
+
+		/*
+		 * Reading these two registers on GC600 rev 0x19 result in a
+		 * unhandled fault: external abort on non-linefetch
+		 */
+		if (!etnaviv_is_model_rev(gpu, GC600, 0x19)) {
+			gpu->identity.product_id = gpu_read(gpu, VIVS_HI_CHIP_PRODUCT_ID);
+			gpu->identity.eco_id = gpu_read(gpu, VIVS_HI_CHIP_ECO_ID);
+		}
 
 		/*
 		 * !!!! HACK ALERT !!!!
-- 
2.26.2

Re: [PATCH v2] drm/etnaviv: fix external abort seen on GC600 rev 0x19

[Ing. Josua Mayer]

Verified that it works as intended on 5.7.10. Thank you very much :)
Feel free to add my tested-by ...

Am 23.08.20 um 21:09 schrieb Christian Gmeiner:
> It looks like that this GPU core triggers an abort when
> reading VIVS_HI_CHIP_PRODUCT_ID and/or VIVS_HI_CHIP_ECO_ID.
> 
> I looked at different versions of Vivante's kernel driver and did
> not found anything about this issue or what feature flag can be
> used. So go the simplest route and do not read these two registers
> on the affected GPU core.
> 
> Signed-off-by: Christian Gmeiner <christian.gmeiner@gmail.com>
> Reported-by: Josua Mayer <josua.mayer@jm0.eu>
> Fixes: 815e45bbd4d3 ("drm/etnaviv: determine product, customer and eco id")
> Cc: stable@vger.kernel.org
> ---
> Changelog:
> 
> V2:
>  - use correct register for conditional reads.
> 
> ---
>  drivers/gpu/drm/etnaviv/etnaviv_gpu.c | 11 +++++++++--
>  1 file changed, 9 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
> index d5a4cd85a0f6..c6404b8d067f 100644
> --- a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
> +++ b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
> @@ -337,9 +337,16 @@ static void etnaviv_hw_identify(struct etnaviv_gpu *gpu)
>  
>  		gpu->identity.model = gpu_read(gpu, VIVS_HI_CHIP_MODEL);
>  		gpu->identity.revision = gpu_read(gpu, VIVS_HI_CHIP_REV);
> -		gpu->identity.product_id = gpu_read(gpu, VIVS_HI_CHIP_PRODUCT_ID);
>  		gpu->identity.customer_id = gpu_read(gpu, VIVS_HI_CHIP_CUSTOMER_ID);
> -		gpu->identity.eco_id = gpu_read(gpu, VIVS_HI_CHIP_ECO_ID);
> +
> +		/*
> +		 * Reading these two registers on GC600 rev 0x19 result in a
> +		 * unhandled fault: external abort on non-linefetch
> +		 */
> +		if (!etnaviv_is_model_rev(gpu, GC600, 0x19)) {
> +			gpu->identity.product_id = gpu_read(gpu, VIVS_HI_CHIP_PRODUCT_ID);
> +			gpu->identity.eco_id = gpu_read(gpu, VIVS_HI_CHIP_ECO_ID);
> +		}
>  
>  		/*
>  		 * !!!! HACK ALERT !!!!
> 

Re: [PATCH v2] drm/etnaviv: fix external abort seen on GC600 rev 0x19

[Lucas Stach]

Am Sonntag, den 23.08.2020, 21:09 +0200 schrieb Christian Gmeiner:
> It looks like that this GPU core triggers an abort when
> reading VIVS_HI_CHIP_PRODUCT_ID and/or VIVS_HI_CHIP_ECO_ID.
> 
> I looked at different versions of Vivante's kernel driver and did
> not found anything about this issue or what feature flag can be
> used. So go the simplest route and do not read these two registers
> on the affected GPU core.
> 
> Signed-off-by: Christian Gmeiner <christian.gmeiner@gmail.com>
> Reported-by: Josua Mayer <josua.mayer@jm0.eu>
> Fixes: 815e45bbd4d3 ("drm/etnaviv: determine product, customer and eco id")
> Cc: stable@vger.kernel.org
> ---
> Changelog:
> 
> V2:
>  - use correct register for conditional reads.

Thanks, I applied this patch to my etnaviv/fixes branch.

Regards,
Lucas

> ---
>  drivers/gpu/drm/etnaviv/etnaviv_gpu.c | 11 +++++++++--
>  1 file changed, 9 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
> index d5a4cd85a0f6..c6404b8d067f 100644
> --- a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
> +++ b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
> @@ -337,9 +337,16 @@ static void etnaviv_hw_identify(struct etnaviv_gpu *gpu)
>  
>  		gpu->identity.model = gpu_read(gpu, VIVS_HI_CHIP_MODEL);
>  		gpu->identity.revision = gpu_read(gpu, VIVS_HI_CHIP_REV);
> -		gpu->identity.product_id = gpu_read(gpu, VIVS_HI_CHIP_PRODUCT_ID);
>  		gpu->identity.customer_id = gpu_read(gpu, VIVS_HI_CHIP_CUSTOMER_ID);
> -		gpu->identity.eco_id = gpu_read(gpu, VIVS_HI_CHIP_ECO_ID);
> +
> +		/*
> +		 * Reading these two registers on GC600 rev 0x19 result in a
> +		 * unhandled fault: external abort on non-linefetch
> +		 */
> +		if (!etnaviv_is_model_rev(gpu, GC600, 0x19)) {
> +			gpu->identity.product_id = gpu_read(gpu, VIVS_HI_CHIP_PRODUCT_ID);
> +			gpu->identity.eco_id = gpu_read(gpu, VIVS_HI_CHIP_ECO_ID);
> +		}
>  
>  		/*
>  		 * !!!! HACK ALERT !!!!