Amiga Storage : a webserver dedicated to Amiga classic users

Description:
Developer:	SpeedGeek
Homepage:	http://eab.abime.net/showpost.php?p=1189690&postcount=1
Readme:	FastCache040+ 2.4 ©SpeedGeek 2020 INTRODUCTION: FastCache040+ is a patch to replace the CachePreDMA() and CachePostDMA() functions of most 68040/060 libraries. While the old functions are adequate they are far from optimal. These old functions have 2x more code then the new ones provided with this patch! Also, the new functions implement a much more efficient method of managing the Copyback cache for DMA. While every system will have some CPU performance loss under DMA conditions, the new functions keep this performance loss to a bare minimum. FEATURES: - Replaces CachePreDMA() and CachePostDMA() with smaller and more efficient code - Replaces complex MMU code with simple and fast DTTR code - Temporarily changes Copyback mode to Write Through for DMA (but only when required!). - Never flushes the ATC! - Never flushes the DC for Chip RAM DMA! - Uses 68040/060 library detection code - Will not patch itself - 100% Assembler code CODE SIZE COMPARISONS: - FastCache040+ 2.4 (NewFunc 190 bytes) - 68060.library 46.7 (OldFunc 304 bytes) - 68040.library 44.2 (OldFunc 414 bytes) REQUIREMENTS: - Amiga with 68040 or 68060 CPU and MMU - 68040.library or 68060.library DISCLAIMER: Use at your own risk. No warranty expressed or implied, etc. DISTRIBUTION: This program is freely distributable but must include this text file. USAGE: - Copy FastCache040 into your C: directory - Execute it from the shell or... - Add it to your startup-sequence (Must be AFTER Setpatch!) - If the install is successful the return code = 0 - If the install is NOT successful the return code = 5 WARNING: Do NOT use this patch with GigaMEM, VMM or any similar virtual memory software! Do NOT use this patch with any code which uses the MMU to write protect or remap modified data structures! NOTES: Remapping a mirror image of the Kickstart ROM with the MMU is OK! The new functions still have one thing in common with the old functions. They do NOT translate virtual addresses as specified in the Amiga RKRM! For more info on the old functions see the Enforcer.guide by Michael Sinz. UPDATE: FastCache040+ v1.7 has been removed. Phase5 68060.library users can optionally use FixMapP5. HISTORY: (Pre 2.0 history deleted) v2.0 - Added code to enable only one DTTR when the Nest count is one. Most systems have only one DMA driver and only need to have 16MB of address space managed for this case. Removed 1.9BR version which was over-rated due to most DMA drivers operating at higher priority than typical user tasks. v2.1 - Reworked the code to fix a problem with Snoopy 2.0 (Aminet). Sorry, this version no longer supports 16 byte aligned cache enabled MEMF_24BIT transfers. NOTE: The original P5 library functions have problems with Snoopy too. I suppose FastCache040+ 2.0 should remain available for the non-snoopers. v2.2 - The Snoopy fix broke MEMF_24BIT transfers. So another bug fix was required. Let's hope it's the last. v2.3 - The 16 byte alignment code is back and now avoids the change of cache mode for this specific case. Removed Continue case from PreDMA since the expected results are the same as the Non-Continue case. The cache disable test code was removed to save the overhead of this very uncommon case. v2.4 - Reworked PostDMA code to fix Nested call cache flush bugs. We really don't want to forget about systems with multiple DMA drivers do we?
Upload Date:	Mar 09 2020
Category:	System/Patchs/040-060
Download:	FastCache040+_2.4.lha
Size:	2 KB
Downloads:	810
Comment(s):