nkeynes@103: /**
nkeynes@108:  * $Id: texcache.c,v 1.3 2006-03-15 13:16:50 nkeynes Exp $
nkeynes@103:  *
nkeynes@103:  * Texture cache. Responsible for maintaining a working set of OpenGL 
nkeynes@103:  * textures. 
nkeynes@103:  *
nkeynes@103:  *
nkeynes@103:  * Copyright (c) 2005 Nathan Keynes.
nkeynes@103:  *
nkeynes@103:  * This program is free software; you can redistribute it and/or modify
nkeynes@103:  * it under the terms of the GNU General Public License as published by
nkeynes@103:  * the Free Software Foundation; either version 2 of the License, or
nkeynes@103:  * (at your option) any later version.
nkeynes@103:  *
nkeynes@103:  * This program is distributed in the hope that it will be useful,
nkeynes@103:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
nkeynes@103:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
nkeynes@103:  * GNU General Public License for more details.
nkeynes@103:  */
nkeynes@103: 
nkeynes@103: #include <assert.h>
nkeynes@103: #include "pvr2/pvr2.h"
nkeynes@103: 
nkeynes@103: /** Specifies the maximum number of OpenGL
nkeynes@103:  * textures we're willing to have open at a time. If more are
nkeynes@103:  * needed, textures will be evicted in LRU order.
nkeynes@103:  */
nkeynes@103: #define MAX_TEXTURES 64
nkeynes@103: 
nkeynes@103: /**
nkeynes@103:  * Data structure:
nkeynes@103:  *
nkeynes@103:  * Main operations:
nkeynes@103:  *    find entry by texture_addr
nkeynes@103:  *    add new entry
nkeynes@103:  *    move entry to tail of lru list
nkeynes@103:  *    remove entry
nkeynes@103:  */
nkeynes@103: 
nkeynes@103: typedef signed short texcache_entry_index;
nkeynes@107: #define EMPTY_ENTRY 0xFF
nkeynes@103: 
nkeynes@107: static texcache_entry_index texcache_free_ptr = 0;
nkeynes@103: static GLuint texcache_free_list[MAX_TEXTURES];
nkeynes@103: 
nkeynes@103: typedef struct texcache_entry {
nkeynes@103:     uint32_t texture_addr;
nkeynes@103:     int width, height, mode;
nkeynes@103:     GLuint texture_id;
nkeynes@103:     texcache_entry_index next;
nkeynes@103:     uint32_t lru_count;
nkeynes@103: } *texcache_entry_t;
nkeynes@103: 
nkeynes@103: static uint8_t texcache_page_lookup[PVR2_RAM_PAGES];
nkeynes@103: static uint32_t texcache_ref_counter;
nkeynes@103: static struct texcache_entry texcache_active_list[MAX_TEXTURES];
nkeynes@103: 
nkeynes@103: /**
nkeynes@108:  * Initialize the texture cache.
nkeynes@103:  */
nkeynes@103: void texcache_init( )
nkeynes@103: {
nkeynes@103:     int i;
nkeynes@103:     for( i=0; i<PVR2_RAM_PAGES; i++ ) {
nkeynes@103: 	texcache_page_lookup[i] = EMPTY_ENTRY;
nkeynes@103:     }
nkeynes@103:     for( i=0; i<MAX_TEXTURES; i++ ) {
nkeynes@103: 	texcache_free_list[i] = i;
nkeynes@103:     }
nkeynes@103:     texcache_free_ptr = 0;
nkeynes@103:     texcache_ref_counter = 0;
nkeynes@103: }
nkeynes@103: 
nkeynes@103: /**
nkeynes@108:  * Setup the initial texture ids (must be called after the GL context is
nkeynes@108:  * prepared)
nkeynes@108:  */
nkeynes@108: void texcache_gl_init( )
nkeynes@108: {
nkeynes@108:     int i;
nkeynes@108:     GLuint texids[MAX_TEXTURES];
nkeynes@108: 
nkeynes@108:     glGenTextures( MAX_TEXTURES, texids );
nkeynes@108:     for( i=0; i<MAX_TEXTURES; i++ ) {
nkeynes@108: 	texcache_active_list[i].texture_id = texids[i];
nkeynes@108:     }
nkeynes@108: }
nkeynes@108: 
nkeynes@108: /**
nkeynes@103:  * Flush all textures from the cache, returning them to the free list.
nkeynes@103:  */
nkeynes@103: void texcache_flush( )
nkeynes@103: {
nkeynes@103:     int i;
nkeynes@103:     /* clear structures */
nkeynes@103:     for( i=0; i<PVR2_RAM_PAGES; i++ ) {
nkeynes@103: 	texcache_page_lookup[i] = EMPTY_ENTRY;
nkeynes@103:     }
nkeynes@103:     for( i=0; i<MAX_TEXTURES; i++ ) {
nkeynes@103: 	texcache_free_list[i] = i;
nkeynes@103:     }
nkeynes@103:     texcache_free_ptr = 0;
nkeynes@103:     texcache_ref_counter = 0;
nkeynes@103: }
nkeynes@103: 
nkeynes@103: /**
nkeynes@103:  * Flush all textures and delete. The cache will be non-functional until
nkeynes@103:  * the next call to texcache_init(). This would typically be done if
nkeynes@103:  * switching GL targets.
nkeynes@103:  */    
nkeynes@103: void texcache_shutdown( )
nkeynes@103: {
nkeynes@103:     GLuint texids[MAX_TEXTURES];
nkeynes@103:     int i;
nkeynes@103:     texcache_flush();
nkeynes@103:     
nkeynes@103:     for( i=0; i<MAX_TEXTURES; i++ ) {
nkeynes@103: 	texids[i] = texcache_active_list[i].texture_id;
nkeynes@103:     }
nkeynes@103:     glDeleteTextures( MAX_TEXTURES, texids );
nkeynes@103: }
nkeynes@103: 
nkeynes@103: /**
nkeynes@103:  * Evict all textures contained in the page identified by a texture address.
nkeynes@103:  */
nkeynes@103: void texcache_invalidate_page( uint32_t texture_addr ) {
nkeynes@103:     uint32_t texture_page = texture_addr >> 12;
nkeynes@103:     texcache_entry_index idx = texcache_page_lookup[texture_page];
nkeynes@103:     if( idx == EMPTY_ENTRY )
nkeynes@103: 	return;
nkeynes@107:     assert( texcache_free_ptr >= 0 );
nkeynes@103:     do {
nkeynes@103: 	texcache_entry_t entry = &texcache_active_list[idx];	
nkeynes@103: 	/* release entry */
nkeynes@103: 	texcache_free_ptr--;
nkeynes@103: 	texcache_free_list[texcache_free_ptr] = idx;
nkeynes@103: 	idx = entry->next;
nkeynes@103: 	entry->next = EMPTY_ENTRY;
nkeynes@103:     } while( idx != EMPTY_ENTRY );
nkeynes@103:     texcache_page_lookup[texture_page] = EMPTY_ENTRY;
nkeynes@103: }
nkeynes@103: 
nkeynes@103: /**
nkeynes@103:  * Evict a single texture from the cache.
nkeynes@103:  * @return the slot of the evicted texture.
nkeynes@103:  */
nkeynes@103: static texcache_entry_index texcache_evict( void )
nkeynes@103: {
nkeynes@103:     /* Full table scan - take over the entry with the lowest lru value */
nkeynes@103:     texcache_entry_index slot = 0;
nkeynes@103:     int lru_value = texcache_active_list[0].lru_count;
nkeynes@103:     int i;
nkeynes@103:     for( i=1; i<MAX_TEXTURES; i++ ) {
nkeynes@103: 	/* FIXME: account for rollover */
nkeynes@103: 	if( texcache_active_list[i].lru_count < lru_value ) {
nkeynes@103: 	    slot = i;
nkeynes@103: 	    lru_value = texcache_active_list[i].lru_count;
nkeynes@103: 	}
nkeynes@103:     }
nkeynes@103:     
nkeynes@103:     /* Remove the selected slot from the lookup table */
nkeynes@103:     uint32_t evict_page = texcache_active_list[slot].texture_addr;
nkeynes@103:     texcache_entry_index replace_next = texcache_active_list[slot].next;
nkeynes@103:     texcache_active_list[slot].next = EMPTY_ENTRY; /* Just for safety */
nkeynes@103:     if( texcache_page_lookup[evict_page] == slot ) {
nkeynes@103: 	texcache_page_lookup[evict_page] = replace_next;
nkeynes@103:     } else {
nkeynes@103: 	texcache_entry_index idx = texcache_page_lookup[evict_page];
nkeynes@103: 	texcache_entry_index next;
nkeynes@103: 	do {
nkeynes@103: 	    next = texcache_active_list[idx].next;
nkeynes@103: 	    if( next == slot ) {
nkeynes@103: 		texcache_active_list[idx].next = replace_next;
nkeynes@103: 		break;
nkeynes@103: 	    }
nkeynes@103: 	    idx = next;
nkeynes@103: 	} while( next != EMPTY_ENTRY );
nkeynes@103:     }
nkeynes@103:     return slot;
nkeynes@103: }
nkeynes@103: 
nkeynes@103: /**
nkeynes@103:  * Load texture data from the given address and parameters into the currently
nkeynes@103:  * bound OpenGL texture.
nkeynes@103:  */
nkeynes@103: static texcache_load_texture( uint32_t texture_addr, int width, int height,
nkeynes@103: 			      int mode ) {
nkeynes@103:     uint32_t bytes = width * height;
nkeynes@108:     int shift = 1;
nkeynes@103:     GLint intFormat, format, type;
nkeynes@108:     int tex_format = mode & PVR2_TEX_FORMAT_MASK;
nkeynes@108: 
nkeynes@108:     if( tex_format == PVR2_TEX_FORMAT_IDX8 ||
nkeynes@108: 	tex_format == PVR2_TEX_FORMAT_IDX4 ) {
nkeynes@108: 	switch( MMIO_READ( PVR2, PALETTECFG ) & 0x03 ) {
nkeynes@108: 	case 0: /* ARGB1555 */
nkeynes@108: 	    intFormat = GL_RGB5_A1;
nkeynes@108: 	    format = GL_RGBA;
nkeynes@108: 	    type = GL_UNSIGNED_SHORT_5_5_5_1;
nkeynes@108: 	    break;
nkeynes@108: 	case 1: 
nkeynes@108: 	    intFormat = GL_RGB;
nkeynes@108: 	    format = GL_RGB;
nkeynes@108: 	    type = GL_UNSIGNED_SHORT_5_6_5;
nkeynes@108: 	    break;
nkeynes@108: 	case 2:
nkeynes@108: 	    intFormat = GL_RGBA4;
nkeynes@108: 	    format = GL_RGBA;
nkeynes@108: 	    type = GL_UNSIGNED_SHORT_4_4_4_4;
nkeynes@108: 	    break;
nkeynes@108: 	case 3:
nkeynes@108: 	    intFormat = GL_RGBA8;
nkeynes@108: 	    format = GL_RGBA;
nkeynes@108: 	    type = GL_UNSIGNED_INT_8_8_8_8;
nkeynes@108: 	    shift = 2;
nkeynes@108: 	    break;
nkeynes@108: 	}
nkeynes@108: 
nkeynes@108: 	if( tex_format == PVR2_TEX_FORMAT_IDX8 ) {
nkeynes@108: 	    int bank = (mode >> 25) &0x03;
nkeynes@108: 	    unsigned char data[bytes<<shift];
nkeynes@108: 	    char *palette = mmio_region_PVR2PAL.mem + (bank * (256 << shift));
nkeynes@108: 	    int i;
nkeynes@108: 	    pvr2_vram64_read( &data, texture_addr, bytes );
nkeynes@108: 	    for( i=bytes-1; i>=0; i-- ) {
nkeynes@108: 		char ch = data[i];
nkeynes@108: 		if( shift == 2 )
nkeynes@108: 		    ((uint32_t *)data)[i] = ((uint32_t *)palette)[ch];
nkeynes@108: 		else
nkeynes@108: 		    ((uint16_t *)data)[i] = ((uint16_t *)palette)[ch];
nkeynes@108: 	    }
nkeynes@108: 	    /* TODO: Detwiddle */
nkeynes@108: 	    glTexImage2D( GL_TEXTURE_2D, 0, intFormat, width, height, 0, format, type,
nkeynes@108: 			  data );
nkeynes@108: 
nkeynes@108: 	}
nkeynes@108:     } else {
nkeynes@108: 	switch( tex_format ) {
nkeynes@108: 	case PVR2_TEX_FORMAT_ARGB1555:
nkeynes@108: 	    bytes <<= 1;
nkeynes@108: 	    intFormat = GL_RGB5_A1;
nkeynes@108: 	    format = GL_RGBA;
nkeynes@108: 	    type = GL_UNSIGNED_SHORT_5_5_5_1;
nkeynes@108: 	    break;
nkeynes@108: 	case PVR2_TEX_FORMAT_RGB565:
nkeynes@108: 	    bytes <<= 1;
nkeynes@108: 	    intFormat = GL_RGBA;
nkeynes@108: 	    format = GL_RGBA;
nkeynes@108: 	    type = GL_UNSIGNED_SHORT_5_6_5;
nkeynes@108: 	    break;
nkeynes@108: 	case PVR2_TEX_FORMAT_ARGB4444:
nkeynes@108: 	    bytes <<= 1;
nkeynes@108: 	    intFormat = GL_RGBA4;
nkeynes@108: 	    format = GL_RGBA;
nkeynes@108: 	    type = GL_UNSIGNED_SHORT_4_4_4_4;
nkeynes@108: 	    break;
nkeynes@108: 	case PVR2_TEX_FORMAT_YUV422:
nkeynes@108: 	    ERROR( "YUV textures not supported" );
nkeynes@108: 	    break;
nkeynes@108: 	case PVR2_TEX_FORMAT_BUMPMAP:
nkeynes@108: 	    ERROR( "Bumpmap not supported" );
nkeynes@108: 	    break;
nkeynes@108: 	case PVR2_TEX_FORMAT_IDX4:
nkeynes@108: 	    /* Supported? */
nkeynes@108: 	    bytes >>= 1;
nkeynes@108: 	    intFormat = GL_INTENSITY4;
nkeynes@108: 	    format = GL_COLOR_INDEX;
nkeynes@108: 	    type = GL_UNSIGNED_BYTE;
nkeynes@108: 	    shift = 0;
nkeynes@108: 	    break;
nkeynes@108: 	case PVR2_TEX_FORMAT_IDX8:
nkeynes@108: 	    intFormat = GL_INTENSITY8;
nkeynes@108: 	    format = GL_COLOR_INDEX;
nkeynes@108: 	    type = GL_UNSIGNED_BYTE;
nkeynes@108: 	    shift = 0;
nkeynes@108: 	    break;
nkeynes@108: 	}
nkeynes@108: 	
nkeynes@108: 	unsigned char data[bytes];
nkeynes@108: 	/* load data from image, detwiddling/uncompressing as required */
nkeynes@108: 	if( PVR2_TEX_IS_COMPRESSED(mode) ) {
nkeynes@108: 	    ERROR( "VQ Compression not supported" );
nkeynes@108: 	} else {
nkeynes@108: 	    pvr2_vram64_read( &data, texture_addr, bytes );
nkeynes@108: 	    if( PVR2_TEX_IS_TWIDDLED(mode) ) {
nkeynes@108: 		/* Untwiddle */
nkeynes@108: 	    }
nkeynes@108: 	}
nkeynes@108: 
nkeynes@108: 	/* Pass to GL */
nkeynes@108: 	glTexImage2D( GL_TEXTURE_2D, 0, intFormat, width, height, 0, format, type,
nkeynes@108: 		      data );
nkeynes@103:     }
nkeynes@108:     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
nkeynes@108:     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
nkeynes@103: }
nkeynes@103: 
nkeynes@103: /**
nkeynes@103:  * Return a texture ID for the texture specified at the supplied address
nkeynes@103:  * and given parameters (the same sequence of bytes could in theory have
nkeynes@103:  * multiple interpretations). We use the texture address as the primary
nkeynes@103:  * index, but allow for multiple instances at each address. The texture
nkeynes@103:  * will be bound to the GL_TEXTURE_2D target before being returned.
nkeynes@103:  * 
nkeynes@103:  * If the texture has already been bound, return the ID to which it was
nkeynes@103:  * bound. Otherwise obtain an unused texture ID and set it up appropriately.
nkeynes@103:  */
nkeynes@103: GLuint texcache_get_texture( uint32_t texture_addr, int width, int height,
nkeynes@103: 			     int mode )
nkeynes@103: {
nkeynes@103:     uint32_t texture_page = texture_addr >> 12;
nkeynes@103:     texcache_entry_index idx = texcache_page_lookup[texture_page];
nkeynes@103:     while( idx != EMPTY_ENTRY ) {
nkeynes@103: 	texcache_entry_t entry = &texcache_active_list[idx];
nkeynes@103: 	if( entry->texture_addr == texture_addr &&
nkeynes@103: 	    entry->mode == mode &&
nkeynes@103: 	    entry->width == width &&
nkeynes@103: 	    entry->height == height ) {
nkeynes@103: 	    entry->lru_count = texcache_ref_counter++;
nkeynes@103: 	    glBindTexture( GL_TEXTURE_2D, entry->texture_id );
nkeynes@103: 	    return entry->texture_id;
nkeynes@103: 	}
nkeynes@103:         idx = entry->next;
nkeynes@103:     }
nkeynes@103: 
nkeynes@103:     /* Not found - check the free list */
nkeynes@103:     int slot = 0;
nkeynes@103: 
nkeynes@103:     if( texcache_free_ptr < MAX_TEXTURES ) {
nkeynes@103: 	slot = texcache_free_list[texcache_free_ptr++];
nkeynes@103:     } else {
nkeynes@103: 	slot = texcache_evict();
nkeynes@103:     }
nkeynes@103: 
nkeynes@103:     /* Construct new entry */
nkeynes@103:     texcache_active_list[slot].texture_addr = texture_addr;
nkeynes@103:     texcache_active_list[slot].width = width;
nkeynes@103:     texcache_active_list[slot].height = height;
nkeynes@103:     texcache_active_list[slot].mode = mode;
nkeynes@103:     texcache_active_list[slot].lru_count = texcache_ref_counter++;
nkeynes@103: 
nkeynes@103:     /* Add entry to the lookup table */
nkeynes@103:     texcache_active_list[slot].next = texcache_page_lookup[texture_page];
nkeynes@103:     texcache_page_lookup[texture_page] = slot;
nkeynes@103: 
nkeynes@103:     /* Construct the GL texture */
nkeynes@108:     glBindTexture( GL_TEXTURE_2D, texcache_active_list[slot].texture_id );
nkeynes@103:     texcache_load_texture( texture_addr, width, height, mode );
nkeynes@103:     
nkeynes@103:     return texcache_active_list[slot].texture_id;
nkeynes@103: }