2020-08-23 19:24:41

by Christian Gmeiner

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

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 <[email protected]>
Reported-by: Josua Mayer <[email protected]>
Fixes: 815e45bbd4d3 ("drm/etnaviv: determine product, customer and eco id")
Cc: [email protected]
---
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

2020-08-24 09:52:10

by Ing. Josua Mayer

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

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 <[email protected]>
> Reported-by: Josua Mayer <[email protected]>
> Fixes: 815e45bbd4d3 ("drm/etnaviv: determine product, customer and eco id")
> Cc: [email protected]
> ---
> 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 !!!!
>

2020-08-24 10:53:30

by Lucas Stach

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

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 <[email protected]>
> Reported-by: Josua Mayer <[email protected]>
> Fixes: 815e45bbd4d3 ("drm/etnaviv: determine product, customer and eco id")
> Cc: [email protected]
> ---
> 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 !!!!