Re: [PATCH 3/4] drm/v3d: Dump V3D error debug registers in debugfs, and one at reset.

From: Paul Kocialkowski
Date: Fri Apr 19 2019 - 16:04:03 EST


Hi,

On Thu, 2019-04-18 at 17:10 -0700, Eric Anholt wrote:
> Looking at a hang recently, I noticed these registers that might tell
> me if something obvious was wrong. They didn't help in this case, but
> keep it around for the future.

Although I don't have docs to check, looks sane:

Reviewed-by: Paul Kocialkowski <paul.kocialkowski@xxxxxxxxxxx>

Cheers,

Paul

> Signed-off-by: Eric Anholt <eric@xxxxxxxxxx>
> ---
> drivers/gpu/drm/v3d/v3d_debugfs.c | 5 ++++
> drivers/gpu/drm/v3d/v3d_gem.c | 4 +++-
> drivers/gpu/drm/v3d/v3d_regs.h | 38 +++++++++++++++++++++++++++++++
> 3 files changed, 46 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/v3d/v3d_debugfs.c b/drivers/gpu/drm/v3d/v3d_debugfs.c
> index ab652a034959..78a78938e81f 100644
> --- a/drivers/gpu/drm/v3d/v3d_debugfs.c
> +++ b/drivers/gpu/drm/v3d/v3d_debugfs.c
> @@ -58,6 +58,11 @@ static const struct v3d_reg_def v3d_core_reg_defs[] = {
> REGDEF(V3D_GMP_STATUS),
> REGDEF(V3D_GMP_CFG),
> REGDEF(V3D_GMP_VIO_ADDR),
> +
> + REGDEF(V3D_ERR_FDBGO),
> + REGDEF(V3D_ERR_FDBGB),
> + REGDEF(V3D_ERR_FDBGS),
> + REGDEF(V3D_ERR_STAT),
> };
>
> static const struct v3d_reg_def v3d_csd_reg_defs[] = {
> diff --git a/drivers/gpu/drm/v3d/v3d_gem.c b/drivers/gpu/drm/v3d/v3d_gem.c
> index f736e021467a..27e0f87075d9 100644
> --- a/drivers/gpu/drm/v3d/v3d_gem.c
> +++ b/drivers/gpu/drm/v3d/v3d_gem.c
> @@ -109,7 +109,9 @@ v3d_reset(struct v3d_dev *v3d)
> {
> struct drm_device *dev = &v3d->drm;
>
> - DRM_ERROR("Resetting GPU.\n");
> + DRM_DEV_ERROR(dev->dev, "Resetting GPU for hang.\n");
> + DRM_DEV_ERROR(dev->dev, "V3D_ERR_STAT: 0x%08x\n",
> + V3D_CORE_READ(0, V3D_ERR_STAT));
> trace_v3d_reset_begin(dev);
>
> /* XXX: only needed for safe powerdown, not reset. */
> diff --git a/drivers/gpu/drm/v3d/v3d_regs.h b/drivers/gpu/drm/v3d/v3d_regs.h
> index 54c8c4320da0..eda1e289976f 100644
> --- a/drivers/gpu/drm/v3d/v3d_regs.h
> +++ b/drivers/gpu/drm/v3d/v3d_regs.h
> @@ -455,4 +455,42 @@
> # define V3D_CSD_CURRENT_ID0_WG_Y_MASK V3D_MASK(15, 0)
> # define V3D_CSD_CURRENT_ID0_WG_Y_SHIFT 0
>
> +#define V3D_ERR_FDBGO 0x00f04
> +#define V3D_ERR_FDBGB 0x00f08
> +#define V3D_ERR_FDBGR 0x00f0c
> +
> +#define V3D_ERR_FDBGS 0x00f10
> +# define V3D_ERR_FDBGS_INTERPZ_IP_STALL BIT(17)
> +# define V3D_ERR_FDBGS_DEPTHO_FIFO_IP_STALL BIT(16)
> +# define V3D_ERR_FDBGS_XYNRM_IP_STALL BIT(14)
> +# define V3D_ERR_FDBGS_EZREQ_FIFO_OP_VALID BIT(13)
> +# define V3D_ERR_FDBGS_QXYF_FIFO_OP_VALID BIT(12)
> +# define V3D_ERR_FDBGS_QXYF_FIFO_OP_LAST BIT(11)
> +# define V3D_ERR_FDBGS_EZTEST_ANYQVALID BIT(7)
> +# define V3D_ERR_FDBGS_EZTEST_PASS BIT(6)
> +# define V3D_ERR_FDBGS_EZTEST_QREADY BIT(5)
> +# define V3D_ERR_FDBGS_EZTEST_VLF_OKNOVALID BIT(4)
> +# define V3D_ERR_FDBGS_EZTEST_QSTALL BIT(3)
> +# define V3D_ERR_FDBGS_EZTEST_IP_VLFSTALL BIT(2)
> +# define V3D_ERR_FDBGS_EZTEST_IP_PRSTALL BIT(1)
> +# define V3D_ERR_FDBGS_EZTEST_IP_QSTALL BIT(0)
> +
> +#define V3D_ERR_STAT 0x00f20
> +# define V3D_ERR_L2CARE BIT(15)
> +# define V3D_ERR_VCMBE BIT(14)
> +# define V3D_ERR_VCMRE BIT(13)
> +# define V3D_ERR_VCDI BIT(12)
> +# define V3D_ERR_VCDE BIT(11)
> +# define V3D_ERR_VDWE BIT(10)
> +# define V3D_ERR_VPMEAS BIT(9)
> +# define V3D_ERR_VPMEFNA BIT(8)
> +# define V3D_ERR_VPMEWNA BIT(7)
> +# define V3D_ERR_VPMERNA BIT(6)
> +# define V3D_ERR_VPMERR BIT(5)
> +# define V3D_ERR_VPMEWR BIT(4)
> +# define V3D_ERR_VPAERRGL BIT(3)
> +# define V3D_ERR_VPAEBRGL BIT(2)
> +# define V3D_ERR_VPAERGS BIT(1)
> +# define V3D_ERR_VPAEABB BIT(0)
> +
> #endif /* V3D_REGS_H */
--
Paul Kocialkowski, Bootlin
Embedded Linux and kernel engineering
https://bootlin.com