[Freedreno] [PATCH 3/3] drm/msm/dpu: Add interface support for CRC debugfs
Jessica Zhang
quic_jesszhan at quicinc.com
Fri May 27 22:23:17 UTC 2022
On 5/27/2022 12:46 PM, Dmitry Baryshkov wrote:
> On 27/05/2022 21:54, Jessica Zhang wrote:
>> Add support for writing CRC values for the interface block to
>> the debugfs by calling the necessary MISR setup/collect methods.
>>
>> Signed-off-by: Jessica Zhang <quic_jesszhan at quicinc.com>
>> ---
>> drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c | 43 ++++++++++++++-
>> drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.h | 3 +
>> drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c | 61 +++++++++++++++++++++
>> drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h | 22 ++++++++
>> 4 files changed, 128 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
>> b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
>> index ae09466663cf..e830fb1e910d 100644
>> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
>> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
>> @@ -79,6 +79,8 @@ static enum dpu_crtc_crc_source
>> dpu_crtc_parse_crc_source(const char *src_name)
>> if (!strcmp(src_name, "auto") ||
>> !strcmp(src_name, "lm"))
>> return DPU_CRTC_CRC_SOURCE_LAYER_MIXER;
>> + if (!strcmp(src_name, "intf"))
>> + return DPU_CRTC_CRC_SOURCE_INTF;
>> return DPU_CRTC_CRC_SOURCE_INVALID;
>> }
>> @@ -94,8 +96,18 @@ static int dpu_crtc_verify_crc_source(struct
>> drm_crtc *crtc,
>> return -EINVAL;
>> }
>> - if (source == DPU_CRTC_CRC_SOURCE_LAYER_MIXER)
>> + if (source == DPU_CRTC_CRC_SOURCE_LAYER_MIXER) {
>> *values_cnt = crtc_state->num_mixers;
>> + } else if (source == DPU_CRTC_CRC_SOURCE_INTF) {
>> + struct drm_encoder *drm_enc = get_encoder_from_crtc(crtc);
>
> Let's do this correctly from the beginning. The CRTC can drive several
> encoders. Do we want to get CRC from all of them or just from the first
> one?
In the case of multiple encoders, it would be better to collect CRCs
from all of them.
>
>> +
>> + if (!drm_enc) {
>> + DRM_ERROR("no encoder found for crtc %d\n", crtc->index);
>> + return -ENODATA;
>> + }
>> +
>> + *values_cnt = dpu_encoder_get_num_phys(drm_enc);
>> + }
>> return 0;
>> }
>> @@ -116,6 +128,18 @@ static void dpu_crtc_setup_lm_misr(struct
>> dpu_crtc_state *crtc_state)
>> }
>> }
>> +static void dpu_crtc_setup_encoder_misr(struct drm_crtc *crtc)
>> +{
>> + struct drm_encoder *drm_enc = get_encoder_from_crtc(crtc);
>> +
>> + if (!drm_enc) {
>> + DRM_ERROR("no encoder found for crtc %d\n", crtc->index);
>> + return;
>> + }
>> +
>> + dpu_encoder_setup_misr(drm_enc);
>> +}
>> +
>> static int dpu_crtc_set_crc_source(struct drm_crtc *crtc, const char
>> *src_name)
>> {
>> enum dpu_crtc_crc_source source =
>> dpu_crtc_parse_crc_source(src_name);
>> @@ -164,6 +188,8 @@ static int dpu_crtc_set_crc_source(struct drm_crtc
>> *crtc, const char *src_name)
>> if (source == DPU_CRTC_CRC_SOURCE_LAYER_MIXER)
>> dpu_crtc_setup_lm_misr(crtc_state);
>> + else if (source == DPU_CRTC_CRC_SOURCE_INTF)
>> + dpu_crtc_setup_encoder_misr(crtc);
>> cleanup:
>> drm_modeset_unlock(&crtc->mutex);
>> @@ -212,6 +238,18 @@ static int dpu_crtc_get_lm_crc(struct drm_crtc
>> *crtc, struct dpu_crtc_state *crt
>> drm_crtc_accurate_vblank_count(crtc), crcs);
>> }
>> +static int dpu_crtc_get_encoder_crc(struct drm_crtc *crtc)
>> +{
>> + struct drm_encoder *drm_enc = get_encoder_from_crtc(crtc);
>> +
>> + if (!drm_enc) {
>> + DRM_ERROR("no encoder found for crtc %d\n", crtc->index);
>> + return -EINVAL;
>> + }
>> +
>> + return dpu_encoder_get_crc(drm_enc);
>> +}
>> +
>> static int dpu_crtc_get_crc(struct drm_crtc *crtc)
>> {
>> struct dpu_crtc_state *crtc_state;
>> @@ -227,6 +265,9 @@ static int dpu_crtc_get_crc(struct drm_crtc *crtc)
>> if (crtc_state->crc_source == DPU_CRTC_CRC_SOURCE_LAYER_MIXER)
>> return dpu_crtc_get_lm_crc(crtc, crtc_state);
>> + if (crtc_state->crc_source == DPU_CRTC_CRC_SOURCE_INTF)
>> + return dpu_crtc_get_encoder_crc(crtc);
>> +
>> return 0;
>> }
>> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.h
>> b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.h
>> index b8785c394fcc..a60af034905d 100644
>> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.h
>> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.h
>> @@ -1,5 +1,6 @@
>> /* SPDX-License-Identifier: GPL-2.0-only */
>> /*
>> + * Copyright (c) 2022 Qualcomm Innovation Center, Inc. All rights
>> reserved.
>> * Copyright (c) 2015-2021 The Linux Foundation. All rights reserved.
>> * Copyright (C) 2013 Red Hat
>> * Author: Rob Clark <robdclark at gmail.com>
>> @@ -73,11 +74,13 @@ struct dpu_crtc_smmu_state_data {
>> * enum dpu_crtc_crc_source: CRC source
>> * @DPU_CRTC_CRC_SOURCE_NONE: no source set
>> * @DPU_CRTC_CRC_SOURCE_LAYER_MIXER: CRC in layer mixer
>> + * @DPU_CRTC_CRC_SOURCE_INTF: CRC in phys interface
>> * @DPU_CRTC_CRC_SOURCE_INVALID: Invalid source
>> */
>> enum dpu_crtc_crc_source {
>> DPU_CRTC_CRC_SOURCE_NONE = 0,
>> DPU_CRTC_CRC_SOURCE_LAYER_MIXER,
>> + DPU_CRTC_CRC_SOURCE_INTF,
>> DPU_CRTC_CRC_SOURCE_MAX,
>> DPU_CRTC_CRC_SOURCE_INVALID = -1
>> };
>> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
>> b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
>> index 52516eb20cb8..7740515f462d 100644
>> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
>> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
>> @@ -14,6 +14,7 @@
>> #include <drm/drm_crtc.h>
>> #include <drm/drm_file.h>
>> +#include <drm/drm_vblank.h>
>> #include <drm/drm_probe_helper.h>
>> #include "msm_drv.h"
>> @@ -225,6 +226,66 @@ bool dpu_encoder_is_widebus_enabled(const struct
>> drm_encoder *drm_enc)
>> return dpu_enc->wide_bus_en;
>> }
>> +int dpu_encoder_get_num_phys(const struct drm_encoder *drm_enc)
>> +{
>> + struct dpu_encoder_virt *dpu_enc;
>> +
>> + dpu_enc = to_dpu_encoder_virt(drm_enc);
>> +
>> + return dpu_enc->num_phys_encs;
>> +}
>> +
>> +void dpu_encoder_setup_misr(const struct drm_encoder *drm_enc)
>> +{
>> + struct dpu_encoder_virt *dpu_enc;
>> +
>> + int i;
>> +
>> + dpu_enc = to_dpu_encoder_virt(drm_enc);
>> +
>> + for (i = 0; i < dpu_enc->num_phys_encs; i++) {
>> + struct dpu_encoder_phys *phys = dpu_enc->phys_encs[i];
>> +
>> + if (!phys->hw_intf || !phys->hw_intf->ops.setup_misr)
>> + continue;
>
> Does WB support CRC?
AFAIK, no.
>
>> +
>> + phys->hw_intf->ops.setup_misr(phys->hw_intf, true, 1);
>> + }
>> +}
>> +
>> +int dpu_encoder_get_crc(const struct drm_encoder *drm_enc)
>> +{
>> + struct dpu_encoder_virt *dpu_enc;
>> + u32 crcs[MAX_PHYS_ENCODERS_PER_VIRTUAL];
>> +
>> + int i, rc;
>> +
>> + if (!drm_enc->crtc) {
>> + DRM_ERROR("no crtc found for encoder %d\n", drm_enc->index);
>> + return -EINVAL;
>> + }
>> +
>> + dpu_enc = to_dpu_encoder_virt(drm_enc);
>> +
>> + for (i = 0; i < dpu_enc->num_phys_encs; i++) {
>> + struct dpu_encoder_phys *phys = dpu_enc->phys_encs[i];
>> +
>> + if (!phys->hw_intf || !phys->hw_intf->ops.collect_misr)
>> + continue;
>> +
>> + rc = phys->hw_intf->ops.collect_misr(phys->hw_intf, &crcs[i]);
>
> This doesn't look fully correct. Do we need to skip the indices for the
> phys without a backing hw_intf?
Sorry if I'm misunderstanding your question, but don't we need to have a
backing hw_intf (and skip if there isn't any) since the methods for
collecting/setting MISR registers is within the hw_intf?
>
>> +
>
> Extra empty line.
Noted
>
>> + if (rc) {
>> + if (rc != -ENODATA)
>
> Do we need to handle ENODATA in any specific way (like zeroing the
> crcs[i])? If not, I'd suggest to drop this return code. Let's make an
> error always an error.
This is a carry-over from this change [1]. We wanted to have the ENODATA
check to avoid spamming the driver debug logs when CRC is disabled for
this block.
[1]
https://gitlab.freedesktop.org/drm/msm/-/commit/3ce8bdca394fc606b55e7c5ed779d171aaae5d09
Thanks,
Jessica Zhang
>
>> + DRM_DEBUG_DRIVER("MISR read failed\n");
>> + return rc;
>> + }
>> + }
>> +
>> + return drm_crtc_add_crc_entry(drm_enc->crtc, true,
>> + drm_crtc_accurate_vblank_count(drm_enc->crtc), crcs);
>> +}
>> +
>> static void _dpu_encoder_setup_dither(struct dpu_hw_pingpong *hw_pp,
>> unsigned bpc)
>> {
>> struct dpu_hw_dither_cfg dither_cfg = { 0 };
>> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h
>> b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h
>> index 781d41c91994..8345599dd01a 100644
>> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h
>> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h
>> @@ -1,5 +1,6 @@
>> /* SPDX-License-Identifier: GPL-2.0-only */
>> /*
>> + * Copyright (c) 2022 Qualcomm Innovation Center, Inc. All rights
>> reserved.
>> * Copyright (c) 2015-2018, The Linux Foundation. All rights reserved.
>> * Copyright (C) 2013 Red Hat
>> * Author: Rob Clark <robdclark at gmail.com>
>> @@ -174,6 +175,27 @@ int dpu_encoder_get_vsync_count(struct
>> drm_encoder *drm_enc);
>> bool dpu_encoder_is_widebus_enabled(const struct drm_encoder *drm_enc);
>> +/**
>> + * dpu_encoder_get_num_phys - get number of physical encoders
>> contained in virtual
>> + * encoder
>> + * @drm_enc: Pointer to previously created drm encoder structure
>> + * Returns: Number of physical encoders for given drm encoder
>> + */
>> +int dpu_encoder_get_num_phys(const struct drm_encoder *drm_enc);
>> +
>> +/**
>> + * dpu_encoder_setup_misr - enable misr calculations
>> + * @drm_enc: Pointer to previously created drm encoder structure
>> + */
>> +void dpu_encoder_setup_misr(const struct drm_encoder *drm_encoder);
>> +
>> +/**
>> + * dpu_encoder_get_crc - get the crc value from interface blocks
>> + * @drm_enc: Pointer to previously created drm encoder structure
>> + * Returns: 0 on success, error otherwise
>> + */
>> +int dpu_encoder_get_crc(const struct drm_encoder *drm_enc);
>> +
>> /**
>> * dpu_encoder_use_dsc_merge - returns true if the encoder uses DSC
>> merge topology.
>> * @drm_enc: Pointer to previously created drm encoder structure
>
>
> --
> With best wishes
> Dmitry
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