Forum Discussion
Cyclone V speed is much slower
Hello. I am new to Cyclone V. I took my design for Cyclone III and recompiled it with Quartus II web 13.1. From the timing analyzer, I can see that the maximum clock rate is only 84 Mhz while I was getting 131 Mhz with cyclone III at the same C8N speed grade. The timing recommendation is incomprehensible. Would anyone who knows cyclone V well tell me if this is expected? Is Cyclone V significantly slower than Cyclone III? This doesn't make sense.
Thanks a lot. Jixiang34 Replies
- Altera_Forum
Honored Contributor
The warning says there is no sdc file and so the compiler (Timequest) goes default and funny.
- Altera_Forum
Honored Contributor
Thanks. I have checked all warnings. Here is the messages. Sorry, it's long
Critical Warning (138069): Setting INCREMENTAL_COMPILATION to "OFF" is no longer supported. Assignment is ignored. To disable partitions, set the IGNORE_PARTITIONS global assignment to "ON" instead. Warning (20013): Ignored assignments for entity "Flex01" -- entity does not exist in design Warning (20014): Assignment for entity set_instance_assignment -name CLOCK_SETTINGS Clock -to clock -entity Flex01 was ignored Warning (20014): Assignment for entity set_instance_assignment -name CLOCK_SETTINGS clockx2 -to clockx2 -entity Flex01 was ignored Warning (20028): Parallel compilation is not licensed and has been disabled Info (21077): Low junction temperature is 0 degrees C Info (21077): High junction temperature is 85 degrees C Info (332164): Evaluating HDL-embedded SDC commands Info (332165): Entity dcfifo_gkl1 Info (332166): set_false_path -from *rdptr_g* -to *ws_dgrp|dffpipe_d09:dffpipe16|dffe17a* Info (332166): set_false_path -from *delayed_wrptr_g* -to *rs_dgwp|dffpipe_c09:dffpipe12|dffe13a* Critical Warning (332012): Synopsys Design Constraints File file not found: 'Flex01.sdc'. A Synopsys Design Constraints File is required by the TimeQuest Timing Analyzer to get proper timing constraints. Without it, the Compiler will not properly optimize the design. Info (332142): No user constrained generated clocks found in the design. Calling "derive_pll_clocks -create_base_clocks" Info (332110): Deriving PLL clocks Info (332110): create_clock -period 20.833 -waveform {0.000 10.416} -name PLL1IN PLL1IN Info (332110): create_generated_clock -source {myclk|mypll_inst|altera_pll_i|general[0].gpll~FRACTIONAL_PLL|refclkin} -divide_by 8 -multiply_by 125 -duty_cycle 50.00 -name {myclk|mypll_inst|altera_pll_i|general[0].gpll~FRACTIONAL_PLL|vcoph[0]} {myclk|mypll_inst|altera_pll_i|general[0].gpll~FRACTIONAL_PLL|vcoph[0]} Info (332110): create_generated_clock -source {myclk|mypll_inst|altera_pll_i|general[0].gpll~PLL_OUTPUT_COUNTER|vco0ph[0]} -divide_by 6 -duty_cycle 50.00 -name {myclk|mypll_inst|altera_pll_i|general[0].gpll~PLL_OUTPUT_COUNTER|divclk} {myclk|mypll_inst|altera_pll_i|general[0].gpll~PLL_OUTPUT_COUNTER|divclk} Info (332142): No user constrained base clocks found in the design. Calling "derive_clocks -period 1.0" Info (332096): The command derive_clocks did not find any clocks to derive. No clocks were created or changed. Info (332097): The following timing edges are non-unate. TimeQuest will assume pos-unate behavior for these edges in the clock network. Info (332098): Cell: myclk|mypll_inst|altera_pll_i|general[0].gpll~FRACTIONAL_PLL from: refclkin to: fbclk Info (332098): Cell: myclk|mypll_inst|altera_pll_i|general[0].gpll~PLL_OUTPUT_COUNTER from: vco0ph[0] to: divclk Info (332098): Cell: myclk|mypll_inst|altera_pll_i|general[0].gpll~PLL_REFCLK_SELECT from: clkin[0] to: clkout Info (332143): No user constrained clock uncertainty found in the design. Calling "derive_clock_uncertainty" Info (332123): Deriving Clock Uncertainty. Please refer to report_sdc in TimeQuest to see clock uncertainties. Info: Found TIMEQUEST_REPORT_SCRIPT_INCLUDE_DEFAULT_ANALYSIS = ON Info: Analyzing Slow 1100mV 85C Model Critical Warning (332148): Timing requirements not met Info (11105): For recommendations on closing timing, run Report Timing Closure Recommendations in the TimeQuest Timing Analyzer. Info (332146): Worst-case setup slack is -3.839 Info (332119): Slack End Point TNS Clock Info (332119): ========= =================== ===================== Info (332119): -3.839 -1940.855 myclk|mypll_inst|altera_pll_i|general[0].gpll~PLL_OUTPUT_COUNTER|divclk Info (332119): -0.629 -0.629 PLL1IN Info (332146): Worst-case hold slack is -1.915 Info (332119): Slack End Point TNS Clock Info (332119): ========= =================== ===================== Info (332119): -1.915 -1.915 PLL1IN Info (332119): 0.247 0.000 myclk|mypll_inst|altera_pll_i|general[0].gpll~PLL_OUTPUT_COUNTER|divclk Info (332140): No Recovery paths to report Info (332140): No Removal paths to report Info (332146): Worst-case minimum pulse width slack is 0.666 Info (332119): Slack End Point TNS Clock Info (332119): ========= =================== ===================== Info (332119): 0.666 0.000 myclk|mypll_inst|altera_pll_i|general[0].gpll~FRACTIONAL_PLL|vcoph[0] Info (332119): 2.381 0.000 myclk|mypll_inst|altera_pll_i|general[0].gpll~PLL_OUTPUT_COUNTER|divclk Info (332119): 9.090 0.000 PLL1IN Info: Analyzing Slow 1100mV 0C Model Info (334003): Started post-fitting delay annotation Info (334004): Delay annotation completed successfully Info (332097): The following timing edges are non-unate. TimeQuest will assume pos-unate behavior for these edges in the clock network. Info (332098): Cell: myclk|mypll_inst|altera_pll_i|general[0].gpll~FRACTIONAL_PLL from: refclkin to: fbclk Info (332098): Cell: myclk|mypll_inst|altera_pll_i|general[0].gpll~PLL_OUTPUT_COUNTER from: vco0ph[0] to: divclk Info (332098): Cell: myclk|mypll_inst|altera_pll_i|general[0].gpll~PLL_REFCLK_SELECT from: clkin[0] to: clkout Info (332123): Deriving Clock Uncertainty. Please refer to report_sdc in TimeQuest to see clock uncertainties. Critical Warning (332148): Timing requirements not met Info (11105): For recommendations on closing timing, run Report Timing Closure Recommendations in the TimeQuest Timing Analyzer. Info (332146): Worst-case setup slack is -4.424 Info (332119): Slack End Point TNS Clock Info (332119): ========= =================== ===================== Info (332119): -4.424 -2522.605 myclk|mypll_inst|altera_pll_i|general[0].gpll~PLL_OUTPUT_COUNTER|divclk Info (332119): -0.532 -0.532 PLL1IN Info (332146): Worst-case hold slack is -1.981 Info (332119): Slack End Point TNS Clock Info (332119): ========= =================== ===================== Info (332119): -1.981 -1.981 PLL1IN Info (332119): 0.159 0.000 myclk|mypll_inst|altera_pll_i|general[0].gpll~PLL_OUTPUT_COUNTER|divclk Info (332140): No Recovery paths to report Info (332140): No Removal paths to report Info (332146): Worst-case minimum pulse width slack is 0.666 Info (332119): Slack End Point TNS Clock Info (332119): ========= =================== ===================== Info (332119): 0.666 0.000 myclk|mypll_inst|altera_pll_i|general[0].gpll~FRACTIONAL_PLL|vcoph[0] Info (332119): 2.323 0.000 myclk|mypll_inst|altera_pll_i|general[0].gpll~PLL_OUTPUT_COUNTER|divclk Info (332119): 8.993 0.000 PLL1IN Info: Analyzing Fast 1100mV 85C Model Info (334003): Started post-fitting delay annotation Info (334004): Delay annotation completed successfully Info (332097): The following timing edges are non-unate. TimeQuest will assume pos-unate behavior for these edges in the clock network. Info (332098): Cell: myclk|mypll_inst|altera_pll_i|general[0].gpll~FRACTIONAL_PLL from: refclkin to: fbclk Info (332098): Cell: myclk|mypll_inst|altera_pll_i|general[0].gpll~PLL_OUTPUT_COUNTER from: vco0ph[0] to: divclk Info (332098): Cell: myclk|mypll_inst|altera_pll_i|general[0].gpll~PLL_REFCLK_SELECT from: clkin[0] to: clkout Info (332123): Deriving Clock Uncertainty. Please refer to report_sdc in TimeQuest to see clock uncertainties. Info (332146): Worst-case setup slack is 0.000 Info (332119): Slack End Point TNS Clock Info (332119): ========= =================== ===================== Info (332119): 0.000 0.000 PLL1IN Info (332119): 2.113 0.000 - Altera_Forum
Honored Contributor
Here is the summary from the timing report
+-------------------------------------------------------------------------+ ; TimeQuest Timing Analyzer Summary ; +--------------------+----------------------------------------------------+ ; Quartus II Version ; Version 13.1.0 Build 162 10/23/2013 SJ Web Edition ; ; Revision Name ; F ; ; Device Family ; Cyclone III ; ; Device Name ; EP3C40Q240C8 ; ; Timing Models ; Final ; ; Delay Model ; Combined ; ; Rise/Fall Delays ; Enabled ; +--------------------+----------------------------------------------------+ The max speed is 127.98 Mhz +-----------------------------------------------------------------------------------------+ ; Slow 1200mV 85C Model Fmax Summary ; +------------+-----------------+---------------------------------------------------+------+ ; Fmax ; Restricted Fmax ; Clock Name ; Note ; +------------+-----------------+---------------------------------------------------+------+ ; 127.98 MHz ; 127.98 MHz ; myclk|altpll_component|auto_generated|pll1|clk[0] ; ; ; 167.22 MHz ; 167.22 MHz ; PLL1IN ; ; +------------+-----------------+---------------------------------------------------+------+ With the exact same design recompiled for Cyclone V ; TimeQuest Timing Analyzer Summary ; +--------------------+----------------------------------------------------+ ; Quartus II Version ; Version 13.1.0 Build 162 10/23/2013 SJ Web Edition ; ; Revision Name ; F ; ; Device Family ; Cyclone V ; ; Device Name ; 5CEBA4F23C8 ; ; Timing Models ; Final ; ; Delay Model ; Combined ; ; Rise/Fall Delays ; Enabled ; +--------------------+----------------------------------------------------+ The speed is 84.47 Mhz using Quartus ii 13.1 +---------------------------------------------------------------------------------------------------------------+ ; Slow 1100mV 85C Model Fmax Summary ; +------------+-----------------+-------------------------------------------------------------------------+------+ ; Fmax ; Restricted Fmax ; Clock Name ; Note ; +------------+-----------------+-------------------------------------------------------------------------+------+ ; 84.47 MHz ; 84.47 MHz ; myclk|mypll_inst|altera_pll_i|general[0].gpll~PLL_OUTPUT_COUNTER|divclk ; ; ; 218.72 MHz ; 218.72 MHz ; PLL1IN ; ; +------------+-----------------+-------------------------------------------------------------------------+------+ - Altera_Forum
Honored Contributor
Check warnings for any timing constraints that are being ignored because of empty lists.
- Altera_Forum
Honored Contributor
I have just done that. It make no difference. The max freq is still 88mhz.
- Altera_Forum
Honored Contributor
You have to replace pll ip, delete and recreate it then see if there are pll related warnings
- Altera_Forum
Honored Contributor
You are perhaps right but this is a new issue just to Cyclone V. I have done just fine with Cyclone 1-4.
- Altera_Forum
Honored Contributor
It does sound like some timing specs are missed. Have some paths for different names? 88 MHz is very slow and points to poor quality design.
- Altera_Forum
Honored Contributor
I did find a report file .sta.rpt. Is this what I should send you for both devices? Would you give me an email address?
Thanks in advance Jixiang - Altera_Forum
Honored Contributor
That's a good news because I do plan to move all to Cyclone V and the performance is important.
I do not seem to find a way to generate a timing report file. I opened the timeQuest analyzer and I see that I can write a SDC file but that isn't a timing report, is it? Thanks in advance. Jixiang