1 // SPDX-License-Identifier: GPL-2.0+ 2 3 #include <linux/kernel.h> 4 #include <linux/minmax.h> 5 6 #include <drm/drm_blend.h> 7 #include <drm/drm_rect.h> 8 #include <drm/drm_fixed.h> 9 10 #include "vkms_formats.h" 11 12 static size_t pixel_offset(const struct vkms_frame_info *frame_info, int x, int y) 13 { 14 return frame_info->offset + (y * frame_info->pitch) 15 + (x * frame_info->cpp); 16 } 17 18 /* 19 * packed_pixels_addr - Get the pointer to pixel of a given pair of coordinates 20 * 21 * @frame_info: Buffer metadata 22 * @x: The x(width) coordinate of the 2D buffer 23 * @y: The y(Heigth) coordinate of the 2D buffer 24 * 25 * Takes the information stored in the frame_info, a pair of coordinates, and 26 * returns the address of the first color channel. 27 * This function assumes the channels are packed together, i.e. a color channel 28 * comes immediately after another in the memory. And therefore, this function 29 * doesn't work for YUV with chroma subsampling (e.g. YUV420 and NV21). 30 */ 31 static void *packed_pixels_addr(const struct vkms_frame_info *frame_info, 32 int x, int y) 33 { 34 size_t offset = pixel_offset(frame_info, x, y); 35 36 return (u8 *)frame_info->map[0].vaddr + offset; 37 } 38 39 static void *get_packed_src_addr(const struct vkms_frame_info *frame_info, int y) 40 { 41 int x_src = frame_info->src.x1 >> 16; 42 int y_src = y - frame_info->rotated.y1 + (frame_info->src.y1 >> 16); 43 44 return packed_pixels_addr(frame_info, x_src, y_src); 45 } 46 47 static int get_x_position(const struct vkms_frame_info *frame_info, int limit, int x) 48 { 49 if (frame_info->rotation & (DRM_MODE_REFLECT_X | DRM_MODE_ROTATE_270)) 50 return limit - x - 1; 51 return x; 52 } 53 54 static void ARGB8888_to_argb_u16(u8 *src_pixels, struct pixel_argb_u16 *out_pixel) 55 { 56 /* 57 * The 257 is the "conversion ratio". This number is obtained by the 58 * (2^16 - 1) / (2^8 - 1) division. Which, in this case, tries to get 59 * the best color value in a pixel format with more possibilities. 60 * A similar idea applies to others RGB color conversions. 61 */ 62 out_pixel->a = (u16)src_pixels[3] * 257; 63 out_pixel->r = (u16)src_pixels[2] * 257; 64 out_pixel->g = (u16)src_pixels[1] * 257; 65 out_pixel->b = (u16)src_pixels[0] * 257; 66 } 67 68 static void XRGB8888_to_argb_u16(u8 *src_pixels, struct pixel_argb_u16 *out_pixel) 69 { 70 out_pixel->a = (u16)0xffff; 71 out_pixel->r = (u16)src_pixels[2] * 257; 72 out_pixel->g = (u16)src_pixels[1] * 257; 73 out_pixel->b = (u16)src_pixels[0] * 257; 74 } 75 76 static void ARGB16161616_to_argb_u16(u8 *src_pixels, struct pixel_argb_u16 *out_pixel) 77 { 78 u16 *pixels = (u16 *)src_pixels; 79 80 out_pixel->a = le16_to_cpu(pixels[3]); 81 out_pixel->r = le16_to_cpu(pixels[2]); 82 out_pixel->g = le16_to_cpu(pixels[1]); 83 out_pixel->b = le16_to_cpu(pixels[0]); 84 } 85 86 static void XRGB16161616_to_argb_u16(u8 *src_pixels, struct pixel_argb_u16 *out_pixel) 87 { 88 u16 *pixels = (u16 *)src_pixels; 89 90 out_pixel->a = (u16)0xffff; 91 out_pixel->r = le16_to_cpu(pixels[2]); 92 out_pixel->g = le16_to_cpu(pixels[1]); 93 out_pixel->b = le16_to_cpu(pixels[0]); 94 } 95 96 static void RGB565_to_argb_u16(u8 *src_pixels, struct pixel_argb_u16 *out_pixel) 97 { 98 u16 *pixels = (u16 *)src_pixels; 99 100 s64 fp_rb_ratio = drm_fixp_div(drm_int2fixp(65535), drm_int2fixp(31)); 101 s64 fp_g_ratio = drm_fixp_div(drm_int2fixp(65535), drm_int2fixp(63)); 102 103 u16 rgb_565 = le16_to_cpu(*pixels); 104 s64 fp_r = drm_int2fixp((rgb_565 >> 11) & 0x1f); 105 s64 fp_g = drm_int2fixp((rgb_565 >> 5) & 0x3f); 106 s64 fp_b = drm_int2fixp(rgb_565 & 0x1f); 107 108 out_pixel->a = (u16)0xffff; 109 out_pixel->r = drm_fixp2int_round(drm_fixp_mul(fp_r, fp_rb_ratio)); 110 out_pixel->g = drm_fixp2int_round(drm_fixp_mul(fp_g, fp_g_ratio)); 111 out_pixel->b = drm_fixp2int_round(drm_fixp_mul(fp_b, fp_rb_ratio)); 112 } 113 114 /** 115 * vkms_compose_row - compose a single row of a plane 116 * @stage_buffer: output line with the composed pixels 117 * @plane: state of the plane that is being composed 118 * @y: y coordinate of the row 119 * 120 * This function composes a single row of a plane. It gets the source pixels 121 * through the y coordinate (see get_packed_src_addr()) and goes linearly 122 * through the source pixel, reading the pixels and converting it to 123 * ARGB16161616 (see the pixel_read() callback). For rotate-90 and rotate-270, 124 * the source pixels are not traversed linearly. The source pixels are queried 125 * on each iteration in order to traverse the pixels vertically. 126 */ 127 void vkms_compose_row(struct line_buffer *stage_buffer, struct vkms_plane_state *plane, int y) 128 { 129 struct pixel_argb_u16 *out_pixels = stage_buffer->pixels; 130 struct vkms_frame_info *frame_info = plane->frame_info; 131 u8 *src_pixels = get_packed_src_addr(frame_info, y); 132 int limit = min_t(size_t, drm_rect_width(&frame_info->dst), stage_buffer->n_pixels); 133 134 for (size_t x = 0; x < limit; x++, src_pixels += frame_info->cpp) { 135 int x_pos = get_x_position(frame_info, limit, x); 136 137 if (drm_rotation_90_or_270(frame_info->rotation)) 138 src_pixels = get_packed_src_addr(frame_info, x + frame_info->rotated.y1) 139 + frame_info->cpp * y; 140 141 plane->pixel_read(src_pixels, &out_pixels[x_pos]); 142 } 143 } 144 145 /* 146 * The following functions take an line of argb_u16 pixels from the 147 * src_buffer, convert them to a specific format, and store them in the 148 * destination. 149 * 150 * They are used in the `compose_active_planes` to convert and store a line 151 * from the src_buffer to the writeback buffer. 152 */ 153 static void argb_u16_to_ARGB8888(u8 *dst_pixels, struct pixel_argb_u16 *in_pixel) 154 { 155 /* 156 * This sequence below is important because the format's byte order is 157 * in little-endian. In the case of the ARGB8888 the memory is 158 * organized this way: 159 * 160 * | Addr | = blue channel 161 * | Addr + 1 | = green channel 162 * | Addr + 2 | = Red channel 163 * | Addr + 3 | = Alpha channel 164 */ 165 dst_pixels[3] = DIV_ROUND_CLOSEST(in_pixel->a, 257); 166 dst_pixels[2] = DIV_ROUND_CLOSEST(in_pixel->r, 257); 167 dst_pixels[1] = DIV_ROUND_CLOSEST(in_pixel->g, 257); 168 dst_pixels[0] = DIV_ROUND_CLOSEST(in_pixel->b, 257); 169 } 170 171 static void argb_u16_to_XRGB8888(u8 *dst_pixels, struct pixel_argb_u16 *in_pixel) 172 { 173 dst_pixels[3] = 0xff; 174 dst_pixels[2] = DIV_ROUND_CLOSEST(in_pixel->r, 257); 175 dst_pixels[1] = DIV_ROUND_CLOSEST(in_pixel->g, 257); 176 dst_pixels[0] = DIV_ROUND_CLOSEST(in_pixel->b, 257); 177 } 178 179 static void argb_u16_to_ARGB16161616(u8 *dst_pixels, struct pixel_argb_u16 *in_pixel) 180 { 181 u16 *pixels = (u16 *)dst_pixels; 182 183 pixels[3] = cpu_to_le16(in_pixel->a); 184 pixels[2] = cpu_to_le16(in_pixel->r); 185 pixels[1] = cpu_to_le16(in_pixel->g); 186 pixels[0] = cpu_to_le16(in_pixel->b); 187 } 188 189 static void argb_u16_to_XRGB16161616(u8 *dst_pixels, struct pixel_argb_u16 *in_pixel) 190 { 191 u16 *pixels = (u16 *)dst_pixels; 192 193 pixels[3] = 0xffff; 194 pixels[2] = cpu_to_le16(in_pixel->r); 195 pixels[1] = cpu_to_le16(in_pixel->g); 196 pixels[0] = cpu_to_le16(in_pixel->b); 197 } 198 199 static void argb_u16_to_RGB565(u8 *dst_pixels, struct pixel_argb_u16 *in_pixel) 200 { 201 u16 *pixels = (u16 *)dst_pixels; 202 203 s64 fp_rb_ratio = drm_fixp_div(drm_int2fixp(65535), drm_int2fixp(31)); 204 s64 fp_g_ratio = drm_fixp_div(drm_int2fixp(65535), drm_int2fixp(63)); 205 206 s64 fp_r = drm_int2fixp(in_pixel->r); 207 s64 fp_g = drm_int2fixp(in_pixel->g); 208 s64 fp_b = drm_int2fixp(in_pixel->b); 209 210 u16 r = drm_fixp2int(drm_fixp_div(fp_r, fp_rb_ratio)); 211 u16 g = drm_fixp2int(drm_fixp_div(fp_g, fp_g_ratio)); 212 u16 b = drm_fixp2int(drm_fixp_div(fp_b, fp_rb_ratio)); 213 214 *pixels = cpu_to_le16(r << 11 | g << 5 | b); 215 } 216 217 void vkms_writeback_row(struct vkms_writeback_job *wb, 218 const struct line_buffer *src_buffer, int y) 219 { 220 struct vkms_frame_info *frame_info = &wb->wb_frame_info; 221 int x_dst = frame_info->dst.x1; 222 u8 *dst_pixels = packed_pixels_addr(frame_info, x_dst, y); 223 struct pixel_argb_u16 *in_pixels = src_buffer->pixels; 224 int x_limit = min_t(size_t, drm_rect_width(&frame_info->dst), src_buffer->n_pixels); 225 226 for (size_t x = 0; x < x_limit; x++, dst_pixels += frame_info->cpp) 227 wb->pixel_write(dst_pixels, &in_pixels[x]); 228 } 229 230 void *get_pixel_conversion_function(u32 format) 231 { 232 switch (format) { 233 case DRM_FORMAT_ARGB8888: 234 return &ARGB8888_to_argb_u16; 235 case DRM_FORMAT_XRGB8888: 236 return &XRGB8888_to_argb_u16; 237 case DRM_FORMAT_ARGB16161616: 238 return &ARGB16161616_to_argb_u16; 239 case DRM_FORMAT_XRGB16161616: 240 return &XRGB16161616_to_argb_u16; 241 case DRM_FORMAT_RGB565: 242 return &RGB565_to_argb_u16; 243 default: 244 return NULL; 245 } 246 } 247 248 void *get_pixel_write_function(u32 format) 249 { 250 switch (format) { 251 case DRM_FORMAT_ARGB8888: 252 return &argb_u16_to_ARGB8888; 253 case DRM_FORMAT_XRGB8888: 254 return &argb_u16_to_XRGB8888; 255 case DRM_FORMAT_ARGB16161616: 256 return &argb_u16_to_ARGB16161616; 257 case DRM_FORMAT_XRGB16161616: 258 return &argb_u16_to_XRGB16161616; 259 case DRM_FORMAT_RGB565: 260 return &argb_u16_to_RGB565; 261 default: 262 return NULL; 263 } 264 } 265