Rev |
Log message |
Author |
Age |
Path |
183 |
Cleaned up the system so that !CYC implies !STB as well. |
dgisselq |
2789d 02h |
/zipcpu/trunk/rtl/ |
182 |
Bug fix for fast memories. This now works for memories with single cycle
latencies. |
dgisselq |
2789d 02h |
/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 |
2789d 02h |
/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 |
2789d 02h |
/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 |
2789d 02h |
/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 |
2789d 02h |
/zipcpu/trunk/rtl/ |
177 |
Fixed the illegal address logic to be more precise. |
dgisselq |
2789d 02h |
/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 |
2789d 02h |
/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 |
2789d 02h |
/zipcpu/trunk/rtl/ |
174 |
Simplified the divide to improve timing performance. |
dgisselq |
2789d 02h |
/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 |
2881d 22h |
/zipcpu/trunk/rtl/ |
157 |
Added the divide unit to the list of ZipCPU dependencies. |
dgisselq |
2881d 22h |
/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 |
2914d 21h |
/zipcpu/trunk/rtl/ |
144 |
Makes the auto-reload capability a configuration option, and fills out the
reset so that it is properly implemented. |
dgisselq |
2914d 21h |
/zipcpu/trunk/rtl/ |
140 |
Minor changes, but fixes build of zippy_tb.cpp. |
dgisselq |
2918d 10h |
/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 |
2921d 07h |
/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 |
2935d 22h |
/zipcpu/trunk/rtl/ |
132 |
Lots of minor bug fixes. |
dgisselq |
2935d 22h |
/zipcpu/trunk/rtl/ |
131 |
Fixed a variable use before declaration error. |
dgisselq |
2935d 22h |
/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 |
2935d 22h |
/zipcpu/trunk/rtl/ |
129 |
Bug fix. Fixes some ugly race conditions that would cause code from the wrong
address to be executed. |
dgisselq |
2935d 22h |
/zipcpu/trunk/rtl/ |
128 |
Cleaned up some comments. |
dgisselq |
2935d 22h |
/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 |
2954d 23h |
/zipcpu/trunk/rtl/ |
115 |
A bug fix, applies to when there are more than 9 interrupt lines into the CPU. |
dgisselq |
2955d 06h |
/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 |
2979d 07h |
/zipcpu/trunk/rtl/ |
91 |
Minor updates. |
dgisselq |
3020d 00h |
/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 |
3020d 00h |
/zipcpu/trunk/rtl/ |
88 |
Eliminated some warnings. The div fixes were to simplify the logic, even though
the result is less readable ... |
dgisselq |
3044d 00h |
/zipcpu/trunk/rtl/ |
84 |
Minor updates. |
dgisselq |
3045d 22h |
/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 |
3045d 22h |
/zipcpu/trunk/rtl/ |