Rev |
Log message |
Author |
Age |
Path |
182 |
Bug fix for fast memories. This now works for memories with single cycle
latencies. |
dgisselq |
2830d 21h |
/zipcpu/trunk/rtl/ |
181 |
Adjusted the wishbone logic to include our wishbone simplification that if
CYC is ever low, STB must be low as well. |
dgisselq |
2830d 21h |
/zipcpu/trunk/rtl/ |
180 |
Cleaned up the stall logic--made it independent of whether or not we are
designed to be alternating or not. |
dgisselq |
2830d 21h |
/zipcpu/trunk/rtl/ |
179 |
Lots of changes, most (all?) of them to the non-pipelined core. The resulting
core is now about 100-120 LUTs smaller when not-pipelined, and yet maintains
the pipelined logic when necessary. |
dgisselq |
2830d 21h |
/zipcpu/trunk/rtl/ |
178 |
Rewrote the parameter controlled logic to be just that: perameter controller,
rather than depending upon generics. The result reduces our area by a couple
LUTs. |
dgisselq |
2830d 21h |
/zipcpu/trunk/rtl/ |
177 |
Fixed the illegal address logic to be more precise. |
dgisselq |
2830d 21h |
/zipcpu/trunk/rtl/ |
176 |
Switched from distributed to block RAM, and adjusted the logic to help
timing closure. The resulting core will build in designs up to 200MHz in
speed. |
dgisselq |
2830d 21h |
/zipcpu/trunk/rtl/ |
175 |
Fixed the carry bit for logical shifts: it is the last bit shifted out of the
register. 0x80000000>>32 yields a 0 with carry set. Anything logically
shifted by a number greater than thirty two clears carry and register. |
dgisselq |
2830d 21h |
/zipcpu/trunk/rtl/ |
174 |
Simplified the divide to improve timing performance. |
dgisselq |
2830d 21h |
/zipcpu/trunk/rtl/ |
160 |
Logic updates, and bug fix corrections to bring this in line with the current
XuLA2-LX25 SoC version. (i.e., the XuLA version was debugged and improved,
this update pushes those improvements to the mainline.) |
dgisselq |
2923d 17h |
/zipcpu/trunk/rtl/ |
157 |
Added the divide unit to the list of ZipCPU dependencies. |
dgisselq |
2923d 17h |
/zipcpu/trunk/rtl/ |
145 |
This fixes the pipelined memory problem that was introduced a while back to
fix ... pipelined memory conflicts. This appears to maintain the success
of the fix, while recovering the pipeline memory performance that was had
before. |
dgisselq |
2956d 16h |
/zipcpu/trunk/rtl/ |
144 |
Makes the auto-reload capability a configuration option, and fills out the
reset so that it is properly implemented. |
dgisselq |
2956d 16h |
/zipcpu/trunk/rtl/ |
140 |
Minor changes, but fixes build of zippy_tb.cpp. |
dgisselq |
2960d 05h |
/zipcpu/trunk/rtl/ |
138 |
This updates the CPU multiply instruction into a set of three instructions.
MPY is a 32x32-bit multiply instruction, returning the low 32-bit result,
MPYUHI returns the upper 32-bits assuming the result was unsigned and MPYSHI
returns the upper 32-bits assuming the result was signed. |
dgisselq |
2963d 02h |
/zipcpu/trunk/rtl/ |
133 |
Changes preceding an instruction set update, which will change the multiply
operation from a 16x16 bit multiply to three types of 32x32-bit multiplies. |
dgisselq |
2977d 17h |
/zipcpu/trunk/rtl/ |
132 |
Lots of minor bug fixes. |
dgisselq |
2977d 17h |
/zipcpu/trunk/rtl/ |
131 |
Fixed a variable use before declaration error. |
dgisselq |
2977d 17h |
/zipcpu/trunk/rtl/ |
130 |
Simplified the lock logic, and removed it when pipelining was not defined. This
also means the file is now dependent upon cpudefs.v. In another change, brev
was modified so as not to update the flags. This makes it useable with GCC
as a potential move or load immediate instruction. |
dgisselq |
2977d 17h |
/zipcpu/trunk/rtl/ |
129 |
Bug fix. Fixes some ugly race conditions that would cause code from the wrong
address to be executed. |
dgisselq |
2977d 17h |
/zipcpu/trunk/rtl/ |
128 |
Cleaned up some comments. |
dgisselq |
2977d 17h |
/zipcpu/trunk/rtl/ |
118 |
Fixes two bugs: 1) in the early branching code within the instruction decoder.
This prevented the early branching from working when built with Xilinx's tools,
while the code worked with Verilator. 2) The CPU was not working with the
traditional cache and early branching disabled. These two bugs masked each
other. The replacement code is simpler. |
dgisselq |
2996d 18h |
/zipcpu/trunk/rtl/ |
115 |
A bug fix, applies to when there are more than 9 interrupt lines into the CPU. |
dgisselq |
2997d 01h |
/zipcpu/trunk/rtl/ |
105 |
Fixed some nasty early branching bugs. Adjusted the Makefile to declare that
cpudefs.h was automatically generated from cpudefs.v, and made sure that
zipbones included the cpudefs.v so it could get the DEBUG_SCOPE define.
In addition, the test.S was updated to test long jumps, the early branching
bug we found, and all three early branching instructions: ADD #x,PC, LOC(PC),PC,
and LDI #x,PC. |
dgisselq |
3021d 02h |
/zipcpu/trunk/rtl/ |
91 |
Minor updates. |
dgisselq |
3061d 19h |
/zipcpu/trunk/rtl/ |
90 |
Removed MOV x(PC),PC from the list of possible early branching instructions.
ADD X,PC and LDI X,PC are now the only recognized early branching instructions.
This was done to spare logic, although I don't think I spared more than a
LUT or two. |
dgisselq |
3061d 19h |
/zipcpu/trunk/rtl/ |
88 |
Eliminated some warnings. The div fixes were to simplify the logic, even though
the result is less readable ... |
dgisselq |
3085d 19h |
/zipcpu/trunk/rtl/ |
84 |
Minor updates. |
dgisselq |
3087d 18h |
/zipcpu/trunk/rtl/ |
83 |
Added a flag to indicate whether an exception took place on the first
or second half of a VLIW instruction--will be zero in non-VLIW mode,
equivalent to the second half of the instruction having caused the
exception. (Expect these flags to be reordered some time in the future into
a less haphazard ordering ...)
Vastly simplified the pipeline logic, primarily for op_stall, but also touched
opA and opB. (Trying to fit within timing on Spartan 6 ...)
Changed division instruction to include a reset on clear_pipeline, to make
certain [BC $addr; DIV Rx,Ry ] works regardless of whether the condition is
true. |
dgisselq |
3087d 18h |
/zipcpu/trunk/rtl/ |
82 |
Found and (I hope) fixed a nasty bug that would send the prefetch into an
endless loop whenever you jumped to an instruction at the last location
in an unloaded cache line. |
dgisselq |
3087d 18h |
/zipcpu/trunk/rtl/ |