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Allow dcp interchange to scanout interchange compressed #449

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31 changes: 29 additions & 2 deletions drivers/gpu/drm/apple/iomfb_plane.h
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Original file line number Diff line number Diff line change
Expand Up @@ -49,6 +49,14 @@ enum dcp_xfer_func {
DCP_XFER_FUNC_HDR = 16,
};

enum dcp_address_format {
DCP_ADDRESS_FORMAT_INTERCHANGE_TILED = 5,
};

enum dcp_compression_type {
DCP_COMPRESSION_TYPE_INTERCHANGE_TILED = 3,
};

struct dcp_rect {
u32 x;
u32 y;
Expand All @@ -67,7 +75,26 @@ struct dcp_plane_info {
u16 tile_size;
u8 tile_w;
u8 tile_h;
u32 unk[13];
u8 unk1[0xd];
u8 address_format;
u8 unk2[0x26];
} __packed;

struct dcp_compression_info {
u32 tile_w;
u32 tile_h;
u32 meta_offset;
u32 data_offset;
u32 tile_meta_bytes;
u32 tiles_w;
u32 tiles_h;
u32 unk1;
u32 compresson_type;
u32 unk3;
u8 _pad1[3];
u32 tile_bytes;
u32 row_stride;
u8 pad2;
} __packed;

struct dcp_component_types {
Expand Down Expand Up @@ -100,7 +127,7 @@ struct dcp_surface {
u64 has_comp;
struct dcp_plane_info planes[DCP_SURF_MAX_PLANES];
u64 has_planes;
u32 compression_info[DCP_SURF_MAX_PLANES][13];
struct dcp_compression_info compression_info[DCP_SURF_MAX_PLANES];
u64 has_compr_info;
u32 unk_num;
u32 unk_denom;
Expand Down
135 changes: 131 additions & 4 deletions drivers/gpu/drm/apple/plane.c
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Original file line number Diff line number Diff line change
Expand Up @@ -9,15 +9,61 @@

#include <drm/drm_atomic.h>
#include <drm/drm_atomic_helper.h>
#include <drm/drm_fourcc.h>
#include <drm/drm_fb_dma_helper.h>
#include <drm/drm_fourcc.h>
#include <drm/drm_framebuffer.h>
#include <drm/drm_gem.h>
#include <drm/drm_gem_dma_helper.h>
#include <drm/drm_plane.h>

#include <linux/align.h>
#include <linux/log2.h>

#ifndef DRM_FORMAT_MOD_APPLE_INTERCHANGE_COMPRESSED
#define DRM_FORMAT_MOD_APPLE_INTERCHANGE_COMPRESSED fourcc_mod_code(APPLE, 3)
#endif

#define FRAC_16_16(mult, div) (((mult) << 16) / (div))

struct apple_interchange_layout {
u32 tiles_width;
u32 tiles_height;
u32 tile_size_B;
u32 meta_offset;
u32 meta_size;
};

static struct apple_interchange_layout
get_apple_interchange_layout(u32 width, u32 height, u32 bpp)
{
const u32 cacheline = 0x80;
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@jannau jannau Mar 2, 2026

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please use a define


u32 tw = DIV_ROUND_UP(width, 16);
u32 th = DIV_ROUND_UP(height, 16);
u32 tsize_B = 16 * 16 * (bpp / 8);
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this should use DIV_ROUND_UP(bpp, 8), not that it matters right now.
That would still be for bit-packed formats. Not sure if dcp supports those or if we want to use them, probably not.
Single component formats with 10- or 12-bit per pixel are more common. Possible that drm_format_info_bpp() includes the padding though.


u32 meta_offset = ALIGN(tw * th * tsize_B, cacheline);

/*
* The metadata buffer contains 8 bytes per 16x16 compression tile.
* Addressing is fully twiddled, so both width and height are padded to
* powers-of-two.
*/
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the comment from the drm_fourcc.h description would be more more appropriate:

/*
 *  ... The metadata section rounds the image dimensions to
 * powers-of-two and contains 8 bytes for each 16x16 compression subtile.
 * Subtiles are interleaved (Morton order).
 */

It's the most up to date description.

unsigned w_tl = DIV_ROUND_UP(roundup_pow_of_two(width), 16);
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isn't this the same as as roundup_pow_of_two(tw)?

unsigned h_tl = DIV_ROUND_UP(roundup_pow_of_two(height), 16);
unsigned B_per_tl = 8;

u32 meta_size = ALIGN(w_tl * h_tl * B_per_tl, cacheline);

return (struct apple_interchange_layout){
.tiles_width = tw,
.tiles_height = th,
.tile_size_B = tsize_B,
.meta_offset = meta_offset,
.meta_size = meta_size,
};
}

static int apple_plane_atomic_check(struct drm_plane *plane,
struct drm_atomic_state *state)
{
Expand Down Expand Up @@ -105,6 +151,38 @@ static int apple_plane_atomic_check(struct drm_plane *plane,
return -EINVAL;
}

/*
* The calculated size of the compression meta data must fit into the size
* of the gem object
*/
for (u32 i = 0; i < new_plane_state->fb->format->num_planes; i++) {
struct drm_framebuffer *fb = new_plane_state->fb;

if (fb->modifier != DRM_FORMAT_MOD_APPLE_INTERCHANGE_COMPRESSED)
continue;

u32 width =
drm_format_info_plane_width(fb->format, fb->width, i);
u32 height =
drm_format_info_plane_height(fb->format, fb->height, i);
u32 bpp = drm_format_info_bpp(fb->format, i);
struct apple_interchange_layout l =
get_apple_interchange_layout(width, height, bpp);

u32 required_size =
fb->offsets[0] + l.meta_offset + l.meta_size;

struct drm_gem_dma_object *obj = drm_fb_dma_get_gem_obj(fb, i);
if (obj && required_size > obj->base.size) {
dev_err_ratelimited(
state->dev->dev,
"dcp: atomic_check, required size of %u bytes is less than gem size of %zu\n",
required_size, obj->base.size);

return -EINVAL;
}
}

return 0;
}

Expand Down Expand Up @@ -248,7 +326,6 @@ static void apple_plane_atomic_update(struct drm_plane *plane,
.stride = fb->pitches[0],
.width = fb->width,
.height = fb->height,
.buf_size = fb->height * fb->pitches[0],
// .surface_id = req->swap.surf_ids[l],

/* Only used for compressed or multiplanar surfaces */
Expand All @@ -257,6 +334,7 @@ static void apple_plane_atomic_update(struct drm_plane *plane,
.pel_h = 1,
.has_comp = 1,
.has_planes = 1,
.has_compr_info = 1,
};

/* Populate plane information for planar formats */
Expand All @@ -279,8 +357,33 @@ static void apple_plane_atomic_update(struct drm_plane *plane,
.tile_h = bh,
};

if (i > 0)
surf->buf_size += surf->planes[i].size;
if (fb->modifier == DRM_FORMAT_MOD_APPLE_INTERCHANGE_COMPRESSED) {
u32 bpp = drm_format_info_bpp(fmt, i);
struct apple_interchange_layout l =
get_apple_interchange_layout(width, height, bpp);

surf->planes[i].tile_w = 16;
surf->planes[i].tile_h = 16;
surf->planes[i].stride = l.tiles_width * l.tile_size_B;
surf->planes[i].size = l.meta_offset + l.meta_size;
surf->planes[i].tile_size = l.tile_size_B;
surf->planes[i].address_format = DCP_ADDRESS_FORMAT_INTERCHANGE_TILED;

surf->compression_info[i] = (struct dcp_compression_info){
.tile_w = 16,
.tile_h = 16,
.data_offset = 0,
.meta_offset = l.meta_offset,
.tile_meta_bytes = 8,
.tiles_w = l.tiles_width,
.tiles_h = l.tiles_height,
.tile_bytes = l.tile_size_B,
.row_stride = l.tiles_width * l.tile_size_B,
.compresson_type = DCP_COMPRESSION_TYPE_INTERCHANGE_TILED,
};
}

surf->buf_size += surf->planes[i].size;
}

/* the obvious helper call drm_fb_dma_get_gem_addr() adjusts
Expand Down Expand Up @@ -337,6 +440,28 @@ apple_plane_duplicate_state(struct drm_plane *plane)
return &apple_plane_state->base;
}

static bool apple_plane_format_mod_supported(struct drm_plane *plane,
uint32_t format, uint64_t modifier)
{
if (modifier != DRM_FORMAT_MOD_APPLE_INTERCHANGE_COMPRESSED) {
return true;
}

// interchange is only supported with rgba formats for now.
switch (format) {
case DRM_FORMAT_XRGB2101010:
case DRM_FORMAT_ARGB2101010:
case DRM_FORMAT_XRGB8888:
case DRM_FORMAT_ARGB8888:
case DRM_FORMAT_XBGR8888:
case DRM_FORMAT_ABGR8888:
return true;

default:
return false;
}
}

// void apple_plane_destroy_state(struct drm_plane *plane,
// struct drm_plane_state *state)
// {
Expand All @@ -350,6 +475,7 @@ static const struct drm_plane_funcs apple_plane_funcs = {
.atomic_duplicate_state = apple_plane_duplicate_state,
// .atomic_destroy_state = apple_plane_destroy_state,
.atomic_destroy_state = drm_atomic_helper_plane_destroy_state,
.format_mod_supported = apple_plane_format_mod_supported,
};

/*
Expand Down Expand Up @@ -426,6 +552,7 @@ static const u32 dcp_overlay_formats_12_x[] = {
};

u64 apple_format_modifiers[] = {
DRM_FORMAT_MOD_APPLE_INTERCHANGE_COMPRESSED,
DRM_FORMAT_MOD_LINEAR,
DRM_FORMAT_MOD_INVALID
};
Expand Down