cbgfx: add draw_bitmap

draw_bitmap renders a bitmap image on screen with position and sizes
scaled relative to the screen. images are scaled up or down by nearest
neighbor interpolation.

BUG=chrome-os-partner:43444
BRANCH=tot
TEST=drew bitmap images on Samus

Change-Id: Ib599acc85b25626a6aed1fa9884ecd8e169bb860
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: c910c9cdb7efc53aace067bd081aeefc07556811
Original-Reviewed-on: https://chromium-review.googlesource.com/290302
Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Original-Change-Id: Ib599acc85b25626a6aed1fa9884ecd8e169bb860
Original-Signed-off-by: Daisuke Nojiri <dnojiri@chromium.org>
Original-Reviewed-on: https://chromium-review.googlesource.com/295532
Reviewed-on: http://review.coreboot.org/11584
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <pgeorgi@google.com>

2 files changed, 270 insertions, 2 deletions

diff --git a/payloads/libpayload/drivers/video/bitmap.h b/payloads/libpayload/drivers/video/bitmap.h
new file mode 100644
index 0000000000..10d60a38a6
--- /dev/null
+++ b/payloads/libpayload/drivers/video/bitmap.h
@@ -0,0 +1,36 @@
+#ifndef __BITMAP_H__
+#define __BITMAP_H__
+
+#include <stdint.h>
+
+struct bitmap_file_header {
+	uint8_t signature[2];
+	uint32_t file_size;
+	uint16_t reserved[2];
+	uint32_t bitmap_offset;
+} __attribute__ ((__packed__));
+
+/* Bitmap version 3 */
+
+struct bitmap_header_v3 {
+	uint32_t header_size;
+	int32_t width;
+	int32_t height;
+	uint16_t planes;
+	uint16_t bits_per_pixel;
+	uint32_t compression;
+	uint32_t size;
+	int32_t h_res;
+	int32_t v_res;
+	uint32_t colors_used;
+	uint32_t colors_important;
+} __attribute__ ((__packed__));
+
+struct bitmap_palette_element_v3 {
+	uint8_t blue;
+	uint8_t green;
+	uint8_t red;
+	uint8_t reserved;
+} __attribute__ ((__packed__));
+
+#endif /* __BITMAP_H__ */
diff --git a/payloads/libpayload/drivers/video/graphics.c b/payloads/libpayload/drivers/video/graphics.c
index d9270a5a7f..5f1dab7308 100644
--- a/payloads/libpayload/drivers/video/graphics.c
+++ b/payloads/libpayload/drivers/video/graphics.c
@@ -6,6 +6,7 @@
 
 #include <libpayload.h>
 #include <sysinfo.h>
+#include "bitmap.h"
 
 /*
  * 'canvas' is the drawing area located in the center of the screen. It's a
@@ -26,6 +27,16 @@ static uint8_t *fbaddr;
 static char initialized = 0;
 #define LOG(x...)	printf("CBGFX: " x)
 
+/*
+ * This is the range used internally to scale bitmap images. (e.g. 128 = 50%,
+ * 512 = 200%). We choose 256 so that division and multiplication become bit
+ * shift operation.
+ */
+#define BITMAP_SCALE_BASE	256
+
+#define ROUNDUP(x, y)	((x) + ((y) - ((x) % (y))))
+#define ABS(x)		((x) < 0 ? -(x) : (x))
+
 static void add_vectors(struct vector *out,
 			const struct vector *v1, const struct vector *v2)
 {
@@ -33,15 +44,30 @@ static void add_vectors(struct vector *out,
 	out->y = v1->y + v2->y;
 }
 
+static void scale_vector(struct vector *out, const struct vector *in,
+			 size_t scale, size_t base)
+{
+	out->x = in->x * scale / base;
+	out->y = in->y * scale / base;
+}
+
 static void to_canvas(const struct vector *relative, struct vector *absolute)
 {
 	absolute->x = canvas.width * relative->x / CANVAS_SCALE;
 	absolute->y = canvas.height * relative->y / CANVAS_SCALE;
 }
 
+/*
+ * Returns 1 if exclusively within canvas, or 0 if inclusively within canvas.
+ */
 static int within_canvas(const struct vector *v)
 {
-	return v->x < canvas.width && v->y < canvas.height;
+	if (v->x < canvas.width && v->y < canvas.height)
+		return 1;
+	else if (v->x <= canvas.width && v->y <= canvas.height)
+		return 0;
+	else
+		return -1;
 }
 
 static inline uint32_t calculate_color(const struct rgb_color *rgb)
@@ -118,7 +144,7 @@ int draw_box(const struct vector *top_left_rel,
 	to_canvas(top_left_rel, &top_left);
 	to_canvas(size_rel, &size);
 	add_vectors(&t, &top_left, &size);
-	if (!within_canvas(&t)) {
+	if (within_canvas(&t) < 0) {
 		LOG("Box exceeds canvas boundary\n");
 		return CBGFX_ERROR_BOUNDARY;
 	}
@@ -146,3 +172,209 @@ int clear_canvas(struct rgb_color *rgb)
 
 	return draw_box(&coord, &size, rgb);
 }
+
+static int draw_bitmap_v3(const struct vector *top_left,
+			  size_t scale,
+			  const struct vector *image,
+			  const struct bitmap_header_v3 *header,
+			  const struct bitmap_palette_element_v3 *palette,
+			  const uint8_t *pixel_array)
+{
+	const int bpp = header->bits_per_pixel;
+	int32_t dir;
+	struct vector p;
+
+	if (header->compression) {
+		LOG("Compressed bitmaps are not supported\n");
+		return CBGFX_ERROR_BITMAP_FORMAT;
+	}
+	if (bpp >= 16) {
+		LOG("Non-palette bitmaps are not supported\n");
+		return CBGFX_ERROR_BITMAP_FORMAT;
+	}
+	if (bpp != 8) {
+		LOG("Unsupported bits per pixel: %d\n", bpp);
+		return CBGFX_ERROR_BITMAP_FORMAT;
+	}
+	if (scale == 0) {
+		LOG("Scaling out of range\n");
+		return CBGFX_ERROR_SCALE_OUT_OF_RANGE;
+	}
+
+	const int32_t y_stride = ROUNDUP(header->width * bpp / 8, 4);
+	/*
+	 * header->height can be positive or negative.
+	 *
+	 * If it's negative, pixel data is stored from top to bottom. We render
+	 * image from the lowest row to the highest row.
+	 *
+	 * If it's positive, pixel data is stored from bottom to top. We render
+	 * image from the highest row to the lowest row.
+	 */
+	p.y = top_left->y;
+	if (header->height < 0) {
+		dir = 1;
+	} else {
+		p.y += image->height - 1;
+		dir = -1;
+	}
+	/*
+	 * Plot pixels scaled by the nearest neighbor interpolation. We scan
+	 * over the image on canvas (using d) and find the corresponding pixel
+	 * in the bitmap data (using s).
+	 */
+	struct vector s, d;
+	for (d.y = 0; d.y < image->height; d.y++, p.y += dir) {
+		s.y = d.y * BITMAP_SCALE_BASE / scale;
+		const uint8_t *data = pixel_array + s.y * y_stride;
+		p.x = top_left->x;
+		for (d.x = 0; d.x < image->width; d.x++, p.x++) {
+			s.x = d.x * BITMAP_SCALE_BASE / scale;
+			if (s.y * y_stride + s.x > header->size)
+				/*
+				 * Because we're handling integers rounded by
+				 * divisions, we might get here legitimately
+				 * when rendering the last row of a sane image.
+				 */
+				return CBGFX_SUCCESS;
+			uint8_t index = data[s.x];
+			if (index >= header->colors_used) {
+				LOG("Color index exceeds palette boundary\n");
+				return CBGFX_ERROR_BITMAP_DATA;
+			}
+			const struct rgb_color rgb = {
+				.red = palette[index].red,
+				.green = palette[index].green,
+				.blue = palette[index].blue,
+			};
+			set_pixel(&p, calculate_color(&rgb));
+		}
+	}
+
+	return CBGFX_SUCCESS;
+}
+
+static int get_bitmap_file_header(const void *bitmap, size_t size,
+				  struct bitmap_file_header *file_header)
+{
+	const struct bitmap_file_header *fh;
+
+	if (sizeof(*file_header) > size) {
+		LOG("Invalid bitmap data\n");
+		return CBGFX_ERROR_BITMAP_DATA;
+	}
+	fh = (struct bitmap_file_header *)bitmap;
+	if (fh->signature[0] != 'B' || fh->signature[1] != 'M') {
+		LOG("Bitmap signature mismatch\n");
+		return CBGFX_ERROR_BITMAP_SIGNATURE;
+	}
+	file_header->file_size = le32toh(fh->file_size);
+	if (file_header->file_size != size) {
+		LOG("Bitmap file size does not match cbfs file size\n");
+		return CBGFX_ERROR_BITMAP_DATA;
+	}
+	file_header->bitmap_offset = le32toh(fh->bitmap_offset);
+
+	return CBGFX_SUCCESS;
+}
+
+static int parse_bitmap_header_v3(const uint8_t *bitmap,
+			  const struct bitmap_file_header *file_header,
+			  /* ^--- IN / OUT ---v */
+			  struct bitmap_header_v3 *header,
+			  const struct bitmap_palette_element_v3 **palette,
+			  const uint8_t **pixel_array)
+{
+	struct bitmap_header_v3 *h;
+	size_t header_offset = sizeof(struct bitmap_file_header);
+	size_t header_size = sizeof(struct bitmap_header_v3);
+	size_t palette_offset = header_offset + header_size;
+	size_t file_size = file_header->file_size;
+
+	h = (struct bitmap_header_v3 *)(bitmap + header_offset);
+	header->header_size = le32toh(h->header_size);
+	if (header->header_size != header_size) {
+		LOG("Unsupported bitmap format\n");
+		return CBGFX_ERROR_BITMAP_FORMAT;
+	}
+	header->width = le32toh(h->width);
+	header->height = le32toh(h->height);
+	header->bits_per_pixel = le16toh(h->bits_per_pixel);
+	header->compression = le32toh(h->compression);
+	header->size = le32toh(h->size);
+	header->colors_used = le32toh(h->colors_used);
+	size_t palette_size = header->colors_used
+			* sizeof(struct bitmap_palette_element_v3);
+	size_t pixel_offset = file_header->bitmap_offset;
+	if (pixel_offset > file_size) {
+		LOG("Bitmap pixel data exceeds buffer boundary\n");
+		return CBGFX_ERROR_BITMAP_DATA;
+	}
+	if (palette_offset + palette_size > pixel_offset) {
+		LOG("Bitmap palette data exceeds palette boundary\n");
+		return CBGFX_ERROR_BITMAP_DATA;
+	}
+	*palette = (struct bitmap_palette_element_v3 *)(bitmap +
+			palette_offset);
+
+	size_t pixel_size = header->size;
+	if (pixel_size != header->height *
+		ROUNDUP(header->width * header->bits_per_pixel / 8, 4)) {
+		LOG("Bitmap pixel array size does not match expected size\n");
+		return CBGFX_ERROR_BITMAP_DATA;
+	}
+	if (pixel_offset + pixel_size > file_size) {
+		LOG("Bitmap pixel array exceeds buffer boundary\n");
+		return CBGFX_ERROR_BITMAP_DATA;
+	}
+	*pixel_array = bitmap + pixel_offset;
+
+	return CBGFX_SUCCESS;
+}
+
+int draw_bitmap(const struct vector *top_left_rel,
+		size_t scale_rel, const void *bitmap, size_t size)
+{
+	struct bitmap_file_header file_header;
+	struct bitmap_header_v3 header;
+	const struct bitmap_palette_element_v3 *palette;
+	const uint8_t *pixel_array;
+	struct vector top_left, t, image;
+	size_t scale;
+	int rv;
+
+	if (cbgfx_init())
+		return CBGFX_ERROR_INIT;
+
+	rv = get_bitmap_file_header(bitmap, size, &file_header);
+	if (rv)
+		return rv;
+
+	/* only v3 is supported now */
+	rv = parse_bitmap_header_v3(bitmap, &file_header,
+				    &header, &palette, &pixel_array);
+	if (rv)
+		return rv;
+
+	/* convert relative coordinate to canvas coordinate */
+	to_canvas(top_left_rel, &top_left);
+
+	/* convert canvas scale to self scale (relative to image width) */
+	scale = scale_rel * canvas.width * BITMAP_SCALE_BASE /
+			(CANVAS_SCALE * header.width);
+
+	/* calculate height and width of the image on canvas */
+	image.width = header.width;
+	image.height = ABS(header.height);
+	scale_vector(&image, &image, scale, BITMAP_SCALE_BASE);
+
+	/* check whether right bottom corner exceeds canvas boundaries or not */
+	add_vectors(&t, &image, &top_left);
+	if (within_canvas(&t) < 0) {
+		LOG("Bitmap image exceeds canvas boundary\n");
+		return CBGFX_ERROR_BOUNDARY;
+	}
+
+	return draw_bitmap_v3(&top_left, scale, &image,
+			      &header, palette, pixel_array);
+}