Re: [PATCH drm-dp 4/4] drm/hisilicon/hibmc: add dp module in hibmc

[s00452708 <shiyongbang@huawei.com>]

Thanks, I will modify codes according to your comments, and I also
replied some questions or reasons why I did it below.

> On Mon, Sep 30, 2024 at 06:06:10PM +0800, shiyongbang wrote:
>> From: baihan li <libaihan@huawei.com>
>>
>> To support DP interface displaying in hibmc driver. Add
>> a encoder and connector for DP modual.
>>
>> Signed-off-by: baihan li <libaihan@huawei.com>
>> ---
>>   drivers/gpu/drm/hisilicon/hibmc/Makefile      |   2 +-
>>   .../gpu/drm/hisilicon/hibmc/hibmc_drm_dp.c    | 195 ++++++++++++++++++
>>   .../gpu/drm/hisilicon/hibmc/hibmc_drm_drv.c   |  17 +-
>>   .../gpu/drm/hisilicon/hibmc/hibmc_drm_drv.h   |   5 +
>>   4 files changed, 217 insertions(+), 2 deletions(-)
>>   create mode 100644 drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_dp.c
>>
>> diff --git a/drivers/gpu/drm/hisilicon/hibmc/Makefile b/drivers/gpu/drm/hisilicon/hibmc/Makefile
>> index 693036dfab52..8cf74e0d4785 100644
>> --- a/drivers/gpu/drm/hisilicon/hibmc/Makefile
>> +++ b/drivers/gpu/drm/hisilicon/hibmc/Makefile
>> @@ -1,5 +1,5 @@
>>   # SPDX-License-Identifier: GPL-2.0-only
>>   hibmc-drm-y := hibmc_drm_drv.o hibmc_drm_de.o hibmc_drm_vdac.o hibmc_drm_i2c.o \
>> -	       dp/dp_aux.o dp/dp_link.o dp/dp_kapi.o
>> +	       dp/dp_aux.o dp/dp_link.o dp/dp_kapi.o hibmc_drm_dp.o
>>   
>>   obj-$(CONFIG_DRM_HISI_HIBMC) += hibmc-drm.o
>> diff --git a/drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_dp.c b/drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_dp.c
>> new file mode 100644
>> index 000000000000..7a50f1d81aac
>> --- /dev/null
>> +++ b/drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_dp.c
>> @@ -0,0 +1,195 @@
>> +// SPDX-License-Identifier: GPL-2.0-or-later
>> +
>> +#include <linux/io.h>
>> +
>> +#include <drm/drm_probe_helper.h>
>> +#include <drm/drm_simple_kms_helper.h>
>> +#include <drm/drm_atomic_helper.h>
>> +#include <drm/drm_drv.h>
>> +#include <drm/drm_edid.h>
>> +
>> +#include "hibmc_drm_drv.h"
>> +#include "dp/dp_kapi.h"
>> +
>> +static int hibmc_dp_connector_get_modes(struct drm_connector *connector)
>> +{
>> +	int count;
>> +
>> +	count = drm_add_modes_noedid(connector, connector->dev->mode_config.max_width,
>> +				     connector->dev->mode_config.max_height);
>> +	drm_set_preferred_mode(connector, 800, 600); /* default 800x600 */
> What? Please parse EDID instead.
> I'll add aux over i2c r/w and get edid functions in next patch.
>> +
>> +	return count;
>> +}
>> +
>> +static const struct drm_connector_helper_funcs hibmc_dp_conn_helper_funcs = {
>> +	.get_modes = hibmc_dp_connector_get_modes,
>> +};
>> +
>> +static const struct drm_connector_funcs hibmc_dp_conn_funcs = {
>> +	.reset = drm_atomic_helper_connector_reset,
>> +	.fill_modes = drm_helper_probe_single_connector_modes,
>> +	.destroy = drm_connector_cleanup,
>> +	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
>> +	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
>> +};
>> +
>> +static void dp_mode_cfg(struct drm_device *dev, struct dp_mode *dp_mode,
>> +			struct drm_display_mode *mode)
>> +{
>> +	dp_mode->field_rate = drm_mode_vrefresh(mode);
>> +	dp_mode->pixel_clock = mode->clock / 1000; /* 1000: khz to hz */
>> +
>> +	dp_mode->h_total = mode->htotal;
>> +	dp_mode->h_active = mode->hdisplay;
>> +	dp_mode->h_blank = mode->htotal - mode->hdisplay;
>> +	dp_mode->h_front = mode->hsync_start - mode->hdisplay;
>> +	dp_mode->h_sync = mode->hsync_end - mode->hsync_start;
>> +	dp_mode->h_back = mode->htotal - mode->hsync_end;
>> +
>> +	dp_mode->v_total = mode->vtotal;
>> +	dp_mode->v_active = mode->vdisplay;
>> +	dp_mode->v_blank = mode->vtotal - mode->vdisplay;
>> +	dp_mode->v_front = mode->vsync_start - mode->vdisplay;
>> +	dp_mode->v_sync = mode->vsync_end - mode->vsync_start;
>> +	dp_mode->v_back = mode->vtotal - mode->vsync_end;
> No need to copy the bits around. Please use drm_display_mode directly.
>
>> +
>> +	if (mode->flags & DRM_MODE_FLAG_PHSYNC) {
>> +		drm_info(dev, "horizontal sync polarity: positive\n");
>> +		dp_mode->h_pol = 1;
>> +	} else if (mode->flags & DRM_MODE_FLAG_NHSYNC) {
>> +		drm_info(dev, "horizontal sync polarity: negative\n");
>> +		dp_mode->h_pol = 0;
>> +	} else {
>> +		drm_err(dev, "horizontal sync polarity: unknown or not set\n");
>> +	}
>> +
>> +	if (mode->flags & DRM_MODE_FLAG_PVSYNC) {
>> +		drm_info(dev, "vertical sync polarity: positive\n");
>> +		dp_mode->v_pol = 1;
>> +	} else if (mode->flags & DRM_MODE_FLAG_NVSYNC) {
>> +		drm_info(dev, "vertical sync polarity: negative\n");
> No spamming, use DRM debugging macros.
>
>> +		dp_mode->v_pol = 0;
>> +	} else {
>> +		drm_err(dev, "vertical sync polarity: unknown or not set\n");
>> +	}
>> +}
>> +
>> +static int dp_prepare(struct hibmc_dp *dp, struct drm_display_mode *mode)
>> +{
>> +	struct dp_mode dp_mode = {0};
>> +	int ret;
>> +
>> +	hibmc_dp_display_en(dp, false);
>> +
>> +	dp_mode_cfg(dp->drm_dev, &dp_mode, mode);
>> +	ret = hibmc_dp_mode_set(dp, &dp_mode);
>> +	if (ret)
>> +		drm_err(dp->drm_dev, "hibmc dp mode set failed: %d\n", ret);
>> +
>> +	return ret;
>> +}
>> +
>> +static void dp_enable(struct hibmc_dp *dp)
>> +{
>> +	hibmc_dp_display_en(dp, true);
>> +}
>> +
>> +static void dp_disable(struct hibmc_dp *dp)
>> +{
>> +	hibmc_dp_display_en(dp, false);
>> +}
>> +
>> +static int hibmc_dp_hw_init(struct hibmc_drm_private *priv)
>> +{
>> +	int ret;
>> +
>> +	ret = hibmc_dp_kapi_init(&priv->dp);
>> +	if (ret)
>> +		return ret;
>> +
>> +	hibmc_dp_display_en(&priv->dp, false);
>> +
>> +	return 0;
>> +}
>> +
>> +static void hibmc_dp_hw_uninit(struct hibmc_drm_private *priv)
>> +{
>> +	hibmc_dp_kapi_uninit(&priv->dp);
>> +}
> Inline all these one-line wrappers, they serve no purpose.
>
>> +
>> +static void hibmc_dp_encoder_enable(struct drm_encoder *drm_encoder,
>> +				    struct drm_atomic_state *state)
>> +{
>> +	struct hibmc_dp *dp = container_of(drm_encoder, struct hibmc_dp, encoder);
>> +	struct drm_display_mode *mode = &drm_encoder->crtc->state->mode;
>> +
>> +	if (dp_prepare(dp, mode))
>> +		return;
>> +
>> +	dp_enable(dp);
>> +}
>> +
>> +static void hibmc_dp_encoder_disable(struct drm_encoder *drm_encoder,
>> +				     struct drm_atomic_state *state)
>> +{
>> +	struct hibmc_dp *dp = container_of(drm_encoder, struct hibmc_dp, encoder);
>> +
>> +	dp_disable(dp);
>> +}
>> +
>> +static const struct drm_encoder_helper_funcs hibmc_dp_encoder_helper_funcs = {
>> +	.atomic_enable = hibmc_dp_encoder_enable,
>> +	.atomic_disable = hibmc_dp_encoder_disable,
>> +};
>> +
>> +void hibmc_dp_uninit(struct hibmc_drm_private *priv)
>> +{
>> +	hibmc_dp_hw_uninit(priv);
>> +}
>> +
>> +int hibmc_dp_init(struct hibmc_drm_private *priv)
>> +{
>> +	struct drm_device *dev = &priv->dev;
>> +	struct drm_crtc *crtc = &priv->crtc;
>> +	struct hibmc_dp *dp = &priv->dp;
>> +	struct drm_connector *connector = &dp->connector;
>> +	struct drm_encoder *encoder = &dp->encoder;
>> +	int ret;
>> +
>> +	dp->mmio = priv->mmio;
>> +	dp->drm_dev = dev;
>> +
>> +	ret = hibmc_dp_hw_init(priv);
>> +	if (ret) {
>> +		drm_err(dev, "dp hw init failed: %d\n", ret);
>> +		return ret;
>> +	}
>> +
>> +	encoder->possible_crtcs = drm_crtc_mask(crtc);
>> +	ret = drm_simple_encoder_init(dev, encoder, DRM_MODE_ENCODER_TMDS);
> I think drm_simple_foo interfaces are being deprecated. Please copy
> required code into the driver instead.
>
>> +	if (ret) {
>> +		drm_err(dev, "init dp encoder failed: %d\n", ret);
>> +		goto err_init;
>> +	}
>> +
>> +	drm_encoder_helper_add(encoder, &hibmc_dp_encoder_helper_funcs);
>> +
>> +	ret = drm_connector_init(dev, connector, &hibmc_dp_conn_funcs,
>> +				 DRM_MODE_CONNECTOR_DisplayPort);
>> +	if (ret) {
>> +		drm_err(dev, "init dp connector failed: %d\n", ret);
>> +		goto err_init;
>> +	}
>> +
>> +	drm_connector_helper_add(connector, &hibmc_dp_conn_helper_funcs);
>> +
>> +	drm_connector_attach_encoder(connector, encoder);
>> +
>> +	return 0;
>> +
>> +err_init:
>> +	hibmc_dp_hw_uninit(priv);
>> +
>> +	return ret;
>> +}
>> diff --git a/drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_drv.c b/drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_drv.c
>> index 9f9b19ea0587..c90a8db021b0 100644
>> --- a/drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_drv.c
>> +++ b/drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_drv.c
>> @@ -93,6 +93,10 @@ static const struct drm_mode_config_funcs hibmc_mode_funcs = {
>>   
>>   static int hibmc_kms_init(struct hibmc_drm_private *priv)
>>   {
>> +#define DP_HOST_SERDES_CTRL		0x1f001c
>> +#define DP_HOST_SERDES_CTRL_VAL		0x8A00
>> +#define DP_HOST_SERDES_CTRL_MASK	0x7FFFE
>> +
> #defines outside of the function body.
>
>>   	struct drm_device *dev = &priv->dev;
>>   	int ret;
>>   
>> @@ -116,10 +120,17 @@ static int hibmc_kms_init(struct hibmc_drm_private *priv)
>>   		return ret;
>>   	}
>>   
>> +	/* if DP existed, init DP */
>> +	if ((readl(priv->mmio + DP_HOST_SERDES_CTRL) &
>> +	     DP_HOST_SERDES_CTRL_MASK) == DP_HOST_SERDES_CTRL_VAL) {
>> +		ret = hibmc_dp_init(priv);
>> +		if (ret)
>> +			drm_err(dev, "failed to init dp: %d\n", ret);
>> +	}
>> +
>>   	ret = hibmc_vdac_init(priv);
>>   	if (ret) {
>>   		drm_err(dev, "failed to init vdac: %d\n", ret);
>> -		return ret;
> Why?
> We have two display cables, if VGA cannot work, this change makes DP
> still work.
>>   	}
>>   
>>   	return 0;
>> @@ -239,6 +250,7 @@ static int hibmc_hw_init(struct hibmc_drm_private *priv)
>>   
>>   static int hibmc_unload(struct drm_device *dev)
>>   {
>> +	struct hibmc_drm_private *priv = to_hibmc_drm_private(dev);
>>   	struct pci_dev *pdev = to_pci_dev(dev->dev);
>>   
>>   	drm_atomic_helper_shutdown(dev);
>> @@ -247,6 +259,9 @@ static int hibmc_unload(struct drm_device *dev)
>>   
>>   	pci_disable_msi(to_pci_dev(dev->dev));
>>   
>> +	if (priv->dp.encoder.possible_crtcs)
>> +		hibmc_dp_uninit(priv);
>> +
>>   	return 0;
>>   }
>>   
>> diff --git a/drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_drv.h b/drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_drv.h
>> index 6b566f3aeecb..aa79903fe022 100644
>> --- a/drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_drv.h
>> +++ b/drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_drv.h
>> @@ -19,6 +19,7 @@
>>   #include <linux/i2c.h>
>>   
>>   #include <drm/drm_framebuffer.h>
>> +#include "dp/dp_kapi.h"
>>   
>>   struct hibmc_connector {
>>   	struct drm_connector base;
>> @@ -37,6 +38,7 @@ struct hibmc_drm_private {
>>   	struct drm_crtc crtc;
>>   	struct drm_encoder encoder;
>>   	struct hibmc_connector connector;
> It seems this needs to be refactored too, to separate VGA connector /
> encoder / CRTC to a child struct.
>
>> +	struct hibmc_dp dp;
>>   };
>>   
>>   static inline struct hibmc_connector *to_hibmc_connector(struct drm_connector *connector)
>> @@ -59,4 +61,7 @@ int hibmc_vdac_init(struct hibmc_drm_private *priv);
>>   
>>   int hibmc_ddc_create(struct drm_device *drm_dev, struct hibmc_connector *connector);
>>   
>> +int hibmc_dp_init(struct hibmc_drm_private *priv);
>> +void hibmc_dp_uninit(struct hibmc_drm_private *priv);
>> +
>>   #endif
>> -- 
>> 2.33.0
>>