/*************************************************************************** * __________ __ ___. * Open \______ \ ____ ____ | | _\_ |__ _______ ___ * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ / * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < < * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \ * \/ \/ \/ \/ \/ * $Id$ * * Copyright (C) 2007 by Michael Sevakis * * ARM code for memory framebuffer LCDs * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY * KIND, either express or implied. * ****************************************************************************/ #include "config.h" #include "cpu.h" /**************************************************************************** * void lcd_copy_buffer_rect(fb_data *dst, fb_data *src, int width, * int height); */ .section .icode.lcd_copy_buffer_rect, "ax", %progbits .align 2 .global lcd_copy_buffer_rect .type lcd_copy_buffer_rect, %function @ r0 = dst @ r1 = src @ r2 = width @ r3 = height lcd_copy_buffer_rect: @ stmfd sp!, { r4-r11, lr } @ save non-scratch regs mov r5, r2 @ r5 = cached width rsb r4, r2, #LCD_WIDTH @ r4 = LCD_WIDTH - width 10: @ copy line @ subs r2, r5, #1 @ r2 = width - 1 beq 40f @ finish line @ one halfword? skip to trailing copy tst r0, #2 @ word aligned? beq 20f @ rem copy @ yes? skip to word copy ldrh r6, [r1], #2 @ copy leading halfword subs r2, r2, #1 @ strh r6, [r0], #2 @ ble 40f @ finish line @ next line if lt or finish @ trailing halfword if eq 20: @ rem copy @ sub r14, r2, #1 @ wrap remaining width mod 16 after word @ align (rw) and r14, r14, #0xe @ r14 = 14, 0, 2, 4, 6, 8, 10, 12 add pc, pc, r14, lsl #3 @ branch to 32-byte align nop @ ldr r6, [r1], #4 @ rw % 16 = 2 or 3 (0) subs r2, r2, #2 @ str r6, [r0], #4 @ b 25f @ copy up done @ ldmia r1!, { r6-r7 } @ rw % 16 = 4 or 5 (2) subs r2, r2, #4 @ stmia r0!, { r6-r7 } @ b 25f @ copy up done @ ldmia r1!, { r6-r8 } @ rw % 16 = 6 or 7 (4) subs r2, r2, #6 @ stmia r0!, { r6-r8 } @ b 25f @ copy up done @ ldmia r1!, { r6-r9 } @ rw % 16 = 8 or 9 (6) subs r2, r2, #8 @ stmia r0!, { r6-r9 } @ b 25f @ copy up done @ ldmia r1!, { r6-r10 } @ rw % 16 = 10 or 11 (8) subs r2, r2, #10 @ stmia r0!, { r6-r10 } @ b 25f @ copy up done @ ldmia r1!, { r6-r11 } @ rw % 16 = 12 or 13 (10) subs r2, r2, #12 @ stmia r0!, { r6-r11 } @ b 25f @ copy up done @ ldmia r1!, { r6-r12 } @ rw % 16 = 14 or 15 (12) subs r2, r2, #14 @ stmia r0!, { r6-r12 } @ 25: @ copy up done @ ble 40f @ finish line @ 30: @ octword loop @ rw % 16 = 0 or 1 (14) ldmia r1!, { r6-r12, r14 } @ copy 16 pixels per loop subs r2, r2, #16 @ stmia r0!, { r6-r12, r14 } @ bgt 30b @ octword loop @ 40: @ finish line @ ldreqh r6, [r1], #2 @ finish last halfword if eq ... add r1, r1, r4, lsl #1 @ streqh r6, [r0], #2 @ ... add r0, r0, r4, lsl #1 @ subs r3, r3, #1 @ next line bgt 10b @ copy line @ ldmpc regs=r4-r11 @ restore regs and return .size lcd_copy_buffer_rect, .-lcd_copy_buffer_rect