Re: [PATCH 07/14] drm/imx: dc: Add DPR channel support

[Liu Ying <victor.liu@nxp.com>]

On 09/19/2025, Frank Li wrote:
> On Fri, Jul 04, 2025 at 05:03:54PM +0800, Liu Ying wrote:
>> Display Prefetch Resolve Channel(DPRC) is a part of a prefetch engine.
>> It fetches display data, transforms it to linear format and stores it
>> to DPRC's RTRAM.  PRG, as the other part of a prefetch engine, acts as
>> a gasket between the RTRAM controller and a FetchUnit.  Add a platform
>> driver to support the DPRC.
>>
>> Signed-off-by: Liu Ying <victor.liu@nxp.com>
>> ---
>>  drivers/gpu/drm/imx/dc/Kconfig   |   1 +
>>  drivers/gpu/drm/imx/dc/Makefile  |   6 +-
>>  drivers/gpu/drm/imx/dc/dc-dprc.c | 499 +++++++++++++++++++++++++++++++++++++++
>>  drivers/gpu/drm/imx/dc/dc-dprc.h |  35 +++
>>  drivers/gpu/drm/imx/dc/dc-drv.c  |   1 +
>>  drivers/gpu/drm/imx/dc/dc-drv.h  |   1 +
>>  drivers/gpu/drm/imx/dc/dc-prg.c  |  12 +
>>  drivers/gpu/drm/imx/dc/dc-prg.h  |   4 +
>>  8 files changed, 556 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/imx/dc/Kconfig b/drivers/gpu/drm/imx/dc/Kconfig
>> index 415993207f2e3487f09602050fa9284fd0955cc7..507dc9a92d96be225cd9b10968a037dad286b327 100644
>> --- a/drivers/gpu/drm/imx/dc/Kconfig
>> +++ b/drivers/gpu/drm/imx/dc/Kconfig
> 
> ...
> 
>> +		return false;
>> +
>> +	if (!dc_prg_stride_supported(dprc->prg, prg_stride, baddr))
>> +		return false;
>> +
>> +	return true;
>> +}
>> +
>> +static int dc_dprc_probe(struct platform_device *pdev)
>> +{
>> +	struct device *dev = &pdev->dev;
>> +	struct device_node *np = dev->of_node;
>> +	struct resource *res;
>> +	void __iomem *base;
>> +	struct dc_dprc *dprc;
>> +	int ret, wrap_irq;
> 
> If have new version, try keep reverse christmas tree order for nice look.

Ack.

> 
>> +
>> +	dprc = devm_kzalloc(dev, sizeof(*dprc), GFP_KERNEL);
>> +	if (!dprc)
>> +		return -ENOMEM;
>> +
>> +	ret = imx_scu_get_handle(&dprc->ipc_handle);
>> +	if (ret)
>> +		return dev_err_probe(dev, ret, "failed to get SCU ipc handle\n");
>> +
>> +	base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
>> +	if (IS_ERR(base))
>> +		return PTR_ERR(base);
>> +
>> +	dprc->reg = devm_regmap_init_mmio(dev, base, &dc_dprc_regmap_config);
>> +	if (IS_ERR(dprc->reg))
>> +		return PTR_ERR(dprc->reg);
>> +
>> +	wrap_irq = platform_get_irq_byname(pdev, "dpr_wrap");
>> +	if (wrap_irq < 0)
>> +		return -ENODEV;
>> +
>> +	dprc->clk_apb = devm_clk_get(dev, "apb");
>> +	if (IS_ERR(dprc->clk_apb))
>> +		return dev_err_probe(dev, PTR_ERR(dprc->clk_apb),
>> +				     "failed to get APB clock\n");
>> +
>> +	dprc->clk_b = devm_clk_get(dev, "b");
>> +	if (IS_ERR(dprc->clk_b))
>> +		return dev_err_probe(dev, PTR_ERR(dprc->clk_b),
>> +				     "failed to get B clock\n");
>> +
>> +	dprc->clk_rtram = devm_clk_get(dev, "rtram");
>> +	if (IS_ERR(dprc->clk_rtram))
>> +		return dev_err_probe(dev, PTR_ERR(dprc->clk_rtram),
>> +				     "failed to get RTRAM clock\n");
> 
> use clk bulk API will simple clock handlers code, include suspend/resume
> codes.

Ack.

> 
> Frank
>> +
>> +	ret = of_property_read_u32(np, "fsl,sc-resource", &dprc->sc_resource);
>> +	if (ret) {
>> +		dev_err(dev, "failed to get SC resource %d\n", ret);
>> +		return ret;
>> +	}
>> +
>> +	dprc->prg = dc_prg_lookup_by_phandle(dev, "fsl,prgs", 0);
>> +	if (!dprc->prg)
>> +		return dev_err_probe(dev, -EPROBE_DEFER,
>> +				     "failed to lookup PRG\n");
>> +
>> +	dc_prg_set_dprc(dprc->prg, dprc);
>> +
>> +	dprc->dev = dev;
>> +	spin_lock_init(&dprc->lock);
>> +
>> +	ret = devm_request_irq(dev, wrap_irq, dc_dprc_wrap_irq_handler,
>> +			       IRQF_SHARED, dev_name(dev), dprc);
>> +	if (ret < 0) {
>> +		dev_err(dev, "failed to request dpr_wrap IRQ(%d): %d\n",
>> +			wrap_irq, ret);
>> +		return ret;
>> +	}
>> +
>> +	dev_set_drvdata(dev, dprc);
>> +
>> +	ret = devm_pm_runtime_enable(dev);
>> +	if (ret)
>> +		return dev_err_probe(dev, ret, "failed to enable PM runtime\n");
>> +
>> +	return 0;
>> +}
>> +
>> +static int dc_dprc_runtime_suspend(struct device *dev)
>> +{
>> +	struct dc_dprc *dprc = dev_get_drvdata(dev);
>> +
>> +	clk_disable_unprepare(dprc->clk_rtram);
>> +	clk_disable_unprepare(dprc->clk_b);
>> +	clk_disable_unprepare(dprc->clk_apb);
>> +
>> +	return 0;
>> +}
>> +
>> +static int dc_dprc_runtime_resume(struct device *dev)
>> +{
>> +	struct dc_dprc *dprc = dev_get_drvdata(dev);
>> +	int ret;
>> +
>> +	ret = clk_prepare_enable(dprc->clk_apb);
>> +	if (ret) {
>> +		dev_err(dev, "failed to enable APB clock: %d\n", ret);
>> +		goto err1;
>> +	}
>> +
>> +	ret = clk_prepare_enable(dprc->clk_b);
>> +	if (ret) {
>> +		dev_err(dev, "failed to enable B clock: %d\n", ret);
>> +		goto err2;
>> +	}
>> +
>> +	ret = clk_prepare_enable(dprc->clk_rtram);
>> +	if (ret) {
>> +		dev_err(dev, "failed to enable RTRAM clock: %d\n", ret);
>> +		goto err3;
>> +	}
>> +
>> +	dc_dprc_reset(dprc);
>> +
>> +	/* disable all control IRQs and enable all error IRQs */
>> +	guard(spinlock_irqsave)(&dprc->lock);
>> +	regmap_write(dprc->reg, IRQ_MASK, IRQ_CTRL_MASK);
>> +
>> +	return 0;
>> +err3:
>> +	clk_disable_unprepare(dprc->clk_b);
>> +err2:
>> +	clk_disable_unprepare(dprc->clk_apb);
>> +err1:
>> +	return ret;
>> +}
>> +
>> +static const struct dev_pm_ops dc_dprc_pm_ops = {
>> +	RUNTIME_PM_OPS(dc_dprc_runtime_suspend, dc_dprc_runtime_resume, NULL)
>> +};
>> +
>> +static const struct of_device_id dc_dprc_dt_ids[] = {
>> +	{ .compatible = "fsl,imx8qxp-dpr-channel", },
>> +	{ /* sentinel */ }
>> +};
>> +
>> +struct platform_driver dc_dprc_driver = {
>> +	.probe = dc_dprc_probe,
>> +	.driver = {
>> +		.name = "imx8-dc-dpr-channel",
>> +		.suppress_bind_attrs = true,
>> +		.of_match_table = dc_dprc_dt_ids,
>> +		.pm = pm_ptr(&dc_dprc_pm_ops),
>> +	},
>> +};
>> diff --git a/drivers/gpu/drm/imx/dc/dc-dprc.h b/drivers/gpu/drm/imx/dc/dc-dprc.h
>> new file mode 100644
>> index 0000000000000000000000000000000000000000..f977858b57fec2f19775a97dc0baf011ca177c0b
>> --- /dev/null
>> +++ b/drivers/gpu/drm/imx/dc/dc-dprc.h
>> @@ -0,0 +1,35 @@
>> +/* SPDX-License-Identifier: GPL-2.0+ */
>> +/*
>> + * Copyright 2025 NXP
>> + */
>> +
>> +#ifndef __DC_DPRC_H__
>> +#define __DC_DPRC_H__
>> +
>> +#include <linux/device.h>
>> +#include <linux/types.h>
>> +
>> +#include <drm/drm_fourcc.h>
>> +
>> +struct dc_dprc;
>> +
>> +void dc_dprc_configure(struct dc_dprc *dprc, unsigned int stream_id,
>> +		       unsigned int width, unsigned int height,
>> +		       unsigned int stride,
>> +		       const struct drm_format_info *format,
>> +		       dma_addr_t baddr, bool start);
>> +
>> +void dc_dprc_disable_repeat_en(struct dc_dprc *dprc);
>> +
>> +void dc_dprc_disable(struct dc_dprc *dprc);
>> +
>> +void dc_dprc_disable_at_boot(struct dc_dprc *dprc);
>> +
>> +bool dc_dprc_rtram_width_supported(struct dc_dprc *dprc, unsigned int width);
>> +
>> +bool dc_dprc_stride_supported(struct dc_dprc *dprc,
>> +			      unsigned int stride, unsigned int width,
>> +			      const struct drm_format_info *format,
>> +			      dma_addr_t baddr);
>> +
>> +#endif
>> diff --git a/drivers/gpu/drm/imx/dc/dc-drv.c b/drivers/gpu/drm/imx/dc/dc-drv.c
>> index 9bdcfc5aee976ef77bea6b3f6f3ac5f11249798f..17b9c4d0953d46be0a2cd276f06298d848fdcbdd 100644
>> --- a/drivers/gpu/drm/imx/dc/dc-drv.c
>> +++ b/drivers/gpu/drm/imx/dc/dc-drv.c
>> @@ -269,6 +269,7 @@ static struct platform_driver dc_driver = {
>>  static struct platform_driver * const dc_drivers[] = {
>>  	&dc_cf_driver,
>>  	&dc_de_driver,
>> +	&dc_dprc_driver,
>>  	&dc_ed_driver,
>>  	&dc_fg_driver,
>>  	&dc_fl_driver,
>> diff --git a/drivers/gpu/drm/imx/dc/dc-drv.h b/drivers/gpu/drm/imx/dc/dc-drv.h
>> index 557e7d90e4ea8ca2af59027b3152163cf7f9a618..93a8ce4e7c314770b64ccb631628b7e79648c791 100644
>> --- a/drivers/gpu/drm/imx/dc/dc-drv.h
>> +++ b/drivers/gpu/drm/imx/dc/dc-drv.h
>> @@ -74,6 +74,7 @@ int dc_plane_init(struct dc_drm_device *dc_drm, struct dc_plane *dc_plane);
>>
>>  extern struct platform_driver dc_cf_driver;
>>  extern struct platform_driver dc_de_driver;
>> +extern struct platform_driver dc_dprc_driver;
>>  extern struct platform_driver dc_ed_driver;
>>  extern struct platform_driver dc_fg_driver;
>>  extern struct platform_driver dc_fl_driver;
>> diff --git a/drivers/gpu/drm/imx/dc/dc-prg.c b/drivers/gpu/drm/imx/dc/dc-prg.c
>> index 9a1a312c0aeebf47bcf50ffa77971aa3bb431a12..bb6c47133e90f9bc5eb3fb0e30c3f338ec82213b 100644
>> --- a/drivers/gpu/drm/imx/dc/dc-prg.c
>> +++ b/drivers/gpu/drm/imx/dc/dc-prg.c
>> @@ -19,6 +19,7 @@
>>  #include <linux/pm_runtime.h>
>>  #include <linux/regmap.h>
>>
>> +#include "dc-dprc.h"
>>  #include "dc-prg.h"
>>
>>  #define SET			0x4
>> @@ -63,6 +64,7 @@ struct dc_prg {
>>  	struct list_head list;
>>  	struct clk *clk_apb;
>>  	struct clk *clk_rtram;
>> +	struct dc_dprc *dprc;
>>  };
>>
>>  static DEFINE_MUTEX(dc_prg_list_mutex);
>> @@ -217,6 +219,16 @@ dc_prg_lookup_by_phandle(struct device *dev, const char *name, int index)
>>  	return NULL;
>>  }
>>
>> +void dc_prg_set_dprc(struct dc_prg *prg, struct dc_dprc *dprc)
>> +{
>> +	prg->dprc = dprc;
>> +}
>> +
>> +struct dc_dprc *dc_prg_get_dprc(struct dc_prg *prg)
>> +{
>> +	return prg->dprc;
>> +}
>> +
>>  static int dc_prg_probe(struct platform_device *pdev)
>>  {
>>  	struct device *dev = &pdev->dev;
>> diff --git a/drivers/gpu/drm/imx/dc/dc-prg.h b/drivers/gpu/drm/imx/dc/dc-prg.h
>> index 6fd9b050bfa12334720f83ff9ceaf337e3048a54..f29d154f7de597b9d20d5e71303049f6f8b022d6 100644
>> --- a/drivers/gpu/drm/imx/dc/dc-prg.h
>> +++ b/drivers/gpu/drm/imx/dc/dc-prg.h
>> @@ -32,4 +32,8 @@ bool dc_prg_stride_supported(struct dc_prg *prg,
>>  struct dc_prg *
>>  dc_prg_lookup_by_phandle(struct device *dev, const char *name, int index);
>>
>> +void dc_prg_set_dprc(struct dc_prg *prg, struct dc_dprc *dprc);
>> +
>> +struct dc_dprc *dc_prg_get_dprc(struct dc_prg *prg);
>> +
>>  #endif
>>
>> --
>> 2.34.1
>>


-- 
Regards,
Liu Ying