drivers/gpu/drm/tiny/arcpgu.c

Source file repositories/reference/linux-study-clean/drivers/gpu/drm/tiny/arcpgu.c

File Facts

System
Linux kernel
Corpus path
drivers/gpu/drm/tiny/arcpgu.c
Extension
.c
Size
11877 bytes
Lines
436
Domain
Driver Families
Bucket
drivers/gpu
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

struct arcpgu_drm_private {
	struct drm_device	drm;
	void __iomem		*regs;
	struct clk		*clk;
	struct drm_simple_display_pipe pipe;
	struct drm_connector	sim_conn;
};

#define dev_to_arcpgu(x) container_of(x, struct arcpgu_drm_private, drm)

#define pipe_to_arcpgu_priv(x) container_of(x, struct arcpgu_drm_private, pipe)

static inline void arc_pgu_write(struct arcpgu_drm_private *arcpgu,
				 unsigned int reg, u32 value)
{
	iowrite32(value, arcpgu->regs + reg);
}

static inline u32 arc_pgu_read(struct arcpgu_drm_private *arcpgu,
			       unsigned int reg)
{
	return ioread32(arcpgu->regs + reg);
}

#define XRES_DEF	640
#define YRES_DEF	480

#define XRES_MAX	8192
#define YRES_MAX	8192

static int arcpgu_drm_connector_get_modes(struct drm_connector *connector)
{
	int count;

	count = drm_add_modes_noedid(connector, XRES_MAX, YRES_MAX);
	drm_set_preferred_mode(connector, XRES_DEF, YRES_DEF);
	return count;
}

static const struct drm_connector_helper_funcs
arcpgu_drm_connector_helper_funcs = {
	.get_modes = arcpgu_drm_connector_get_modes,
};

static const struct drm_connector_funcs arcpgu_drm_connector_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 int arcpgu_drm_sim_init(struct drm_device *drm, struct drm_connector *connector)
{
	drm_connector_helper_add(connector, &arcpgu_drm_connector_helper_funcs);
	return drm_connector_init(drm, connector, &arcpgu_drm_connector_funcs,
				  DRM_MODE_CONNECTOR_VIRTUAL);
}

#define ENCODE_PGU_XY(x, y)	((((x) - 1) << 16) | ((y) - 1))

static const u32 arc_pgu_supported_formats[] = {
	DRM_FORMAT_RGB565,
	DRM_FORMAT_XRGB8888,
	DRM_FORMAT_ARGB8888,
};

static void arc_pgu_set_pxl_fmt(struct arcpgu_drm_private *arcpgu)
{
	const struct drm_framebuffer *fb = arcpgu->pipe.plane.state->fb;
	uint32_t pixel_format = fb->format->format;
	u32 format = DRM_FORMAT_INVALID;
	int i;
	u32 reg_ctrl;

	for (i = 0; i < ARRAY_SIZE(arc_pgu_supported_formats); i++) {
		if (arc_pgu_supported_formats[i] == pixel_format)
			format = arc_pgu_supported_formats[i];
	}

	if (WARN_ON(format == DRM_FORMAT_INVALID))
		return;

	reg_ctrl = arc_pgu_read(arcpgu, ARCPGU_REG_CTRL);
	if (format == DRM_FORMAT_RGB565)
		reg_ctrl &= ~ARCPGU_MODE_XRGB8888;
	else
		reg_ctrl |= ARCPGU_MODE_XRGB8888;
	arc_pgu_write(arcpgu, ARCPGU_REG_CTRL, reg_ctrl);
}

Annotation

Implementation Notes