On Mon, Oct 26, 2026 at 06:05:13PM +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.
>
> Reviewed-by: Frank Li <[email protected]>
> Acked-by: Maxime Ripard <[email protected]>
> Signed-off-by: Liu Ying <[email protected]>
> ---
> v7:
> - Collect Maxime's A-b tag.
> - Fix dc_dprc_regmap_write_ranges[]. (Sashiko AI bot)
> - Fix dc_dprc_wrap_irq_handler() return value. (Sashiko AI bot)
> - Check runtime PM status in dc_dprc_wrap_irq_handler(). (Sashiko AI bot)
> - Fix DPU_DRPC_MAX_STRIDE macro. (Sashiko AI bot)
> - Support deferral probe if platform_get_irq_byname() fails. (Sashiko AI bot)
> - Avoid dangling prg->dprc by calling dc_prg_set_dprc() properly.
> (Sashiko AI bot)
> - Add dc_dprc_get() helper for consumer device to get DPRC properly.
> - Set use_raw_spinlock flag in regmap configuration to avoid a potential
> hard lockup because dc_dprc_disable_repeat_en() is supposed to be called
> with local irq and preempt disabled.
>
> v6:
> - Include "dc-drv.h" to avoid build warning with C=1.
>
> v3:
> - Call dc_dprc_enable() only when start == true. (Frank)
> - Collect Frank's R-b tag.
>
> v2:
> - Manage clocks with bulk interfaces. (Frank)
> - Sort variables in probe function in reverse Christmas tree fashion. (Frank)
> ---
> drivers/gpu/drm/imx/dc/Kconfig | 1 +
> drivers/gpu/drm/imx/dc/Makefile | 6 +-
> drivers/gpu/drm/imx/dc/dc-dprc.c | 522
> +++++++++++++++++++++++++++++++++++++++
> drivers/gpu/drm/imx/dc/dc-dprc.h | 37 +++
> 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, 581 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/gpu/drm/imx/dc/Kconfig b/drivers/gpu/drm/imx/dc/Kconfig
> index 415993207f2e..507dc9a92d96 100644
> --- a/drivers/gpu/drm/imx/dc/Kconfig
> +++ b/drivers/gpu/drm/imx/dc/Kconfig
> @@ -1,6 +1,7 @@
> config DRM_IMX8_DC
> tristate "Freescale i.MX8 Display Controller Graphics"
> depends on DRM && COMMON_CLK && OF && (ARCH_MXC || COMPILE_TEST)
> + depends on IMX_SCU
> select DRM_CLIENT_SELECTION
> select DRM_GEM_DMA_HELPER
> select DRM_KMS_HELPER
> diff --git a/drivers/gpu/drm/imx/dc/Makefile b/drivers/gpu/drm/imx/dc/Makefile
> index e3a06ee3ce1a..fd5d62783971 100644
> --- a/drivers/gpu/drm/imx/dc/Makefile
> +++ b/drivers/gpu/drm/imx/dc/Makefile
> @@ -1,7 +1,7 @@
> # SPDX-License-Identifier: GPL-2.0
>
> -imx8-dc-drm-objs := dc-cf.o dc-crtc.o dc-de.o dc-drv.o dc-ed.o dc-fg.o
> dc-fl.o \
> - dc-fu.o dc-fw.o dc-ic.o dc-kms.o dc-lb.o dc-pe.o dc-prg.o \
> - dc-plane.o dc-tc.o
> +imx8-dc-drm-objs := dc-cf.o dc-crtc.o dc-de.o dc-dprc.o dc-drv.o dc-ed.o \
> + dc-fg.o dc-fl.o dc-fu.o dc-fw.o dc-ic.o dc-kms.o dc-lb.o \
> + dc-pe.o dc-prg.o dc-plane.o dc-tc.o
>
> obj-$(CONFIG_DRM_IMX8_DC) += imx8-dc-drm.o
> diff --git a/drivers/gpu/drm/imx/dc/dc-dprc.c
> b/drivers/gpu/drm/imx/dc/dc-dprc.c
> new file mode 100644
> index 000000000000..a8ddcd117a52
> --- /dev/null
> +++ b/drivers/gpu/drm/imx/dc/dc-dprc.c
> @@ -0,0 +1,522 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Copyright 2025 NXP
> + */
> +
> +#include <linux/bitfield.h>
> +#include <linux/bits.h>
> +#include <linux/cleanup.h>
> +#include <linux/clk.h>
> +#include <linux/delay.h>
> +#include <linux/device.h>
> +#include <linux/firmware/imx/svc/misc.h>
> +#include <linux/interrupt.h>
> +#include <linux/list.h>
> +#include <linux/module.h>
You can remove the include above. You're not using anything from module.h
AFAIS.
[...]
> +
> +bool dc_dprc_rtram_width_supported(struct dc_dprc *dprc, unsigned int width)
You could probably get rid of dprc as well. You're not using it.
> +{
> + return width <= DPU_DPRC_MAX_RTRAM_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)
> +{
> + unsigned int prg_stride = width * format->cpp[0];
> +
> + if (stride > DPU_DRPC_MAX_STRIDE)
> + return false;
> +
> + if (!dc_prg_stride_supported(dprc->prg, prg_stride, baddr))
> + return false;
> +
> + return true;
> +}
> +
> +struct dc_dprc *dc_dprc_get(struct device *dev, struct dc_dprc *dprc)
> +{
> + struct dc_dprc *iter;
> +
> + guard(mutex)(&dc_dprc_list_mutex);
> + list_for_each_entry(iter, &dc_dprc_list, list) {
> + if (iter == dprc) {
> + device_link_add(dev, dprc->dev,
> + DL_FLAG_AUTOREMOVE_CONSUMER);
> + return dprc;
> + }
> + }
> +
> + return NULL;
> +}
> +
> +static int dc_dprc_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct device_node *np = dev->of_node;
> + struct resource *res;
> + struct dc_dprc *dprc;
> + void __iomem *base;
> + int ret, wrap_irq;
> +
> + 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 dev_err_probe(dev, wrap_irq, "failed to get dpr_wrap
> IRQ\n");
> +
> + dprc->num_clks = devm_clk_bulk_get_all(dev, &dprc->clks);
> + if (dprc->num_clks < 0)
> + return dev_err_probe(dev, dprc->num_clks, "failed to get
> clocks\n");
> +
> + 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;
You could probably use 'return dev_err_probe()', to be consistent with the
other places where you used the same.
--
Thanks,
Laurentiu
