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Hi All, I am facing an issue: One of the register field is configured as : field_a.configure(this, 12, 17, "RO", 0, 12'h0, 1, 0, 1); field_a.set_compare(UVM_NO_CHECK); While doing a reset test, first I reset model then start test. But test fails with : UVM_ERROR -- value read from DUT (0x0000000080001e00) does not match mirrored value (0x00000000XxxXfe00) Basically the fields declared as RO and UVM_NO_CHECK goes X ? Any idea what I am missing or doing wrong ? Thanks.

Hi, How to handle memories wide 8 bits in my register model when register map is built with 32 bits width? Thank you Kristina

Hi there IPXACT needs to capture array of registers properly in a design. Currently there is only one tag ''spirit:dim" to represent an array of registers. This does not enable us to capture an array of register effectively. Consider the following cases: 1. An array of registers can be one dimensional with each element offset by offset address 0x10. 2. An Array of multidimensional registers something like this: register_1[0][0] -> 0x0 register_1[0][1] -> 0x4 register_1[1][0] -> 0x10 register_1[1][1] -> 0x14 ... likewise Is there any way to capture just the address relationship to an array instance within IP-XACT XML tags? (Without using vendorExtensions tag?) We have not been able to capture the above said information inside IPXACT XML.(using only IP-XACT tags) Requesting thoughts regarding the same. Best regards Balasubramanian G

Hello, I was wondering if are there any resources (papers, blogs, posts, best practices) about methodologies to implement UVM RAL for "large" designs (>100K registers and 50K rams)? I tried to do some research online but most of the results never cover "large" designs. I have experience using RAL and doing some customisation to make it work in a particular environment (callbacks, maps, defining specialised registers, sequences) but most of them were "little" (1K regs and 100 rams) I'm interested on any information about aspects such as: Reg model re-usability and portability at sub-system and system level environments Performance: How heavy is the register model, since having this much registers may have a huge performance penalty over simulations Dynamic reconfiguration (I know in 1.2 once your model is locked not much can be done) RAM modelling in RAL (since it the uvm_mem is different from uvm_reg) Register Model Partitioning at block level Register Model limitations on real projects usage Implementation of different sized registers and non uniform mapping General RAL limitations Any material or hints on these topics is really appreciated Apologies for the broad question Thanks -R

Hi, The purpose of this discussion is to understand different possibilities by which the simulation performance, memory usage can be increased. Scoreboard as we understand needs the data/packets/frames etc to be stored/buffered to do a comparison with the actual data out. This works out fine when we have small sized array ranging from few bytes to few thousands of bytes.. However imagine, if we have 100 thousands of bytes and above and there is a need to store them and lets say multiple of such lanes/flows , then this would take a hit on the simulation performance. And this gets worse if we have to reuse and port it to a subsytem/chip level simulations.. With this as the background, i am looking at alternate approach for scoreboards.. In a way is possible avoid scoreboard and check the data as it comes without the need to store the expected/input data. Approach that can be thought of : 1. Generating incremental data pattern and check at the output .. (Comes again with issues like aliasing etc.. and hence need to have longer patterns.) 2. Generation of PRBS stream as the payload of the frame.. and then have a PRBS checker at the output.. and see it remains locked.. (Debug would get worse with this.. if there is a mismatch) 3. Having a byte scoreboard.. something like that.. (Not sure how feasible this is). There are many challenges even with these approach.. I am just wondering if someone has already experienced such cases and what kind of challenges are thrown out.. Appreciate any input on this. Regards, svuvmuser !

Hi All, I am a beginner in the field of hardware verification (1.5 yrs experience only). I have done couple of projects in UVM related to IPs such as UART and GPON. Now, i want to take up the next challenging (due to it's huge state space) self project - UVM based verification of a microprocessor. But i am unaware as to how should i begin? I searched the Web and there is so much material that i am totally confused. Can anybody share what should be my approach? How should i begin? Which microprocessor i should chose? From where can i get the DUT processor code? If anyone has implemented such project, could you please share the details. Thanks Krishna

Hi All, I am working in verification. Where i have to generate reg_block for all the IP's using IPXACT. also top level reg_block which instantiates all the IP level register block using IPXACT. But i am not interested in Ports/Businterface/component. Please advise me what is the best method to do it. Thanks Saravanan

Hi , To whom may correspond I think there is some kind of error in the UVM 1.1d register model. I have been experimenting with the UVM register model and i have seen the following code in uvm_reg_map.svh task uvm_reg_map::do_bus_write (uvm_reg_item rw, uvm_sequencer_base sequencer, uvm_reg_adapter adapter); uvm_reg_addr_t addrs[$]; uvm_reg_map system_map = get_root_map(); int unsigned bus_width = get_n_bytes(); uvm_reg_byte_en_t byte_en = -1; uvm_reg_map_info map_info; int n_bits; int lsb; int skip; int unsigned curr_byte; int n_access_extra, n_access; int n_bits_init; Xget_bus_infoX(rw, map_info, n_bits_init, lsb, skip); addrs=map_info.addr; // if a memory, adjust addresses based on offset if (rw.element_kind == UVM_MEM) foreach (addrs[i]) addrs[i] = addrs[i] + map_info.mem_range.stride * rw.offset; foreach (rw.value[val_idx]) begin: foreach_value uvm_reg_data_t value = rw.value[val_idx]; /* calculate byte_enables */ if (rw.element_kind == UVM_FIELD) begin int temp_be; int idx; n_access_extra = lsb%(bus_width*8); n_access = n_access_extra + n_bits_init; temp_be = n_access_extra; value = value << n_access_extra; while(temp_be >= 8) begin byte_en[idx++] = 0; temp_be -= 8; end temp_be += n_bits_init; while(temp_be > 0) begin byte_en[idx++] = 1; temp_be -= 8; end byte_en &= (1<<idx)-1; for (int i=0; i<skip; i++) void'(addrs.pop_front()); while (addrs.size() > (n_bits_init/(bus_width*8) + 1)) void'(addrs.pop_back()); end curr_byte=0; n_bits= n_bits_init; The code continues but the interesting part is already there. Lets assume we have a register with 4 bytes and 1byte per address granularity (byte_addressing). Now, we do a FIELD access of 8bits length (the first byte of a register). The field is configured "individual_accessible, so UVM should only access that FIELD. The reg2bus should generate that byte request to be written. In other words, the vector "addrs" should have only one byte address. Going to the code, i see that initially the addrs has the 4 address ( the whole register) and when it comes to the "if (rw.element_kind == UVM_FIELD) begin" and it will pop_back()/remove all the exceeding bytes that doesn't need to complete "n_bits_init" of the field access. The problem is here: UVM has //while (addrs.size() > (n_bits_init/(bus_width*8) + 1)) and i think it should be while (addrs.size() > ((n_bits_init-1)/(bus_width*8) + 1)) //ejonalv possible error in UVM? check That is because in case we want to write 8 bits, it will calculate 8/8+1=2 address in the UVM version, but in fact it should require only 1 address. This is of course applicable for the READ variation. Did i misunderstand something? It is very hard to go through the register model without proper documentation in the code. I am looking forward your answer Best Regards Jonathan

I am new to Synopsys VCS. I have been trying to simulate the testbench developed in UVM using VCS in command mode (Linux environment). But, I am not able to get the info displays and the output displays. I am have written the makefile using perl scritps. Can soemeone please tell me where I can find the detail example of using the options in my makefile to run it succesfully while viewing the output displays in command mode

Saw the UVM-SystemC-1.0-beta1 download link, try to install it, but according to the INSTALL file, I can't find "configure" in the package. How could I install it?

I can't find any example in the uvm-systemc preview package which DUT has clock and reset signals. I tried to create clock with sc_clock in sc_main and connected it my dut's clock signal. But it looks the simulation will never finish. So would someone let me know what's the right way to handle the clock and reset signals?

Hello All, I am working on SystemC-UVM based testbench. I have created UVM based testbench using UVM code generator. Here I am using three different agents in UVM generator which I have defined as a part of the configuration file which was further being provided to UVM code generator to generate test bench skeleton. And here, in of the agent driver, the code snippet is as: // Drive the inputs of the DUT UVM_INFO(this->name(),"Driving transaction:",0); req.print(); // TODO put your code here But when I try to read the value in my test-case, then I see an error as: And this error is observed inside print() function, once I comment the line "req.print()" from the above snippet the error is no more observed and my test-case runs fine.

This is a online training batch taught by experts working in Semiconductor Industry. Course starts with System Verilog and covers advanced level UVM. Course schedule is for 2.5 hours on Sat and Sun for 7 weeks. Graduates and working professionals can benefit from this training. Next batch starting on July 11th, 2015! For more details please email vlsitraining@artoflivinghet.org Course schedule is for 2.5 hours on Sat and Sun for 7 weeks. Graduates and working professionals can benefit from this training. For more details please email vlsitraining@artoflivinghet.org

Hi why does phase.find_by_name(.name(uvm_main_phase::get().get_name()), .stay_in_scope(0)); from run_phase and uvm_pkg::uvm_phase run_phase = phase.find_by_name(.name(uvm_run_phase::get().get_name()), .stay_in_scope(0)); from main_phase return null. Is this intentional? I have created a sample example to check, or you can use the attached file as well. https://www.edaplayground.com/x/5Py7 test.svh

Let's say I have the following DUT. The UVM environment contains a chain of models/predictors. Input data flows down this chain and generates the expected CHIP output, which is compared to actual. Pros: verifies top-level functionality. Cons: Does not verify block level functionality. A good start, but I'd like to also verify the blocks in a system setting. So, I create block-level environments, then reuse them at the top level. Awesome, but wait a minute. I still need the top-level verification (Input-to-Output) like in the first example. However, all 3 of my block predictors are being used in their corresponding environments' scoreboards, hooked up to the RTL, via agents. How does one do both? Surely I'm not supposed to instantiate duplicate copies of my block level predictors to create the end-to-end model chain...

Hi, I have a doubt regarding an interface "X" being defined as : Driver code of the VIP: *********************************************** protected virtual X ChipIf; function void connect phase(uvm_phase phase); Y vif_container; super.connect_phase(phase); // Assigning virtual interface assert(uvm_config_object::get(this, "","V_IF_CHIP", temp)); $cast(vif_container, temp); ChipIf = vif_container.get_v_if(); endfunction : connect_phase ********************************************************** From the tb_top of the SoC , where the above VIP pkg is imported along with uvm pkg:*,please let me know how can I "set" the virtual ChipIf?

The VCS implementation of uvm_reg_bit_bash_seq UVM register bit bash sequence performs a model.reset() in the sequence body, before starting the core do_block() task. Due to this reset, any configurations made to the DUT before starting the bit bash sequence is lost in the mirror model, while the DUT still has the configuration intact. This is causing failures during the bit-bash process, resulting in a test fail. There is no knob to override the reset functionality, nor can I extend the sequence and bypass the reset. Any thoughts on this? Any work around for this? ~Chethan

I'm trying out the example for UVM-Connect 2.3 and I can't get a successful compile. The error message is about the "undefined reference to `m__uvm_report_dpi'. I'm using: GCC 4.5.2 on CentOS 5.11 VCS 2015.09-SP2-3 SystemC 2.3.1 SCV 2.0.0 UVM 1.2 UVMC 2.3.0 Appreciate all the help!

The cook book from Mentor tells following and in another thread, the moderator also suggested against using the sub phases of run. However in one of my projects, I do find the need for using them (and infact we had an internal implemention of something similar in our previous OVM version). Are there any thing happening on this front? Is there a risk in using the sub phases if some of that changes in a future version? "The Accellera UVM committee is still developing the use models and APIs for new UVM phasing as it relates to sequences and transactors. In the mean time, our recommendation is to wait until that work is done and the API is stable. There are a number of future articles in this section which will be available here at that time, and which will describe our recommendations for using this technology. These include: How to make your testbench phase aware [Not yet available] How to manage sequences in the context of phasing [Not yet available] How to design reusable transactors that work in the context of phasing [Not yet available] "

Hi, We are using snps ralgen to generate the regmodel. It appears that the ralgen creates only the default map. We would like to have 2 maps for 2 separated if masters. Is there an online example for such case? A post gen script can do one of the following 2 options: 1. add another instance of uvm_reg_map and copy/clone the ready map after finished build 2. add another instance of uvm_reg_map, and duplicate any map1.add_reg and map1.add_submap to map2 Which is preferable? Thanks! Elihai

I see uvm_sequencer_base::wait_for_grant (UVM 1.1d) is a virtual task but accesses a local int g_request_id - is this not a bad coding style? If I were to override this virtual method for debug with much of the code intact tool throws an error for his local bar in a derived SQR class. I extended a SQR class and copied all the code for wait_for_grant and started tweaking - couldn't proceed with that debug due to this member being local. Should it be protected instead of local? Thanks Srini wwww.go2uvm.org

Is it possible to do a uvm_config_db::set() for an object of derived class type using the base class handle and later do a uvm_config_db::get() of same object using the derived class handle Since a base class handle can be used to point to a derived class object and later typecase, I thought this would work, but doesn't seem to be so. Any help will be appreciated? Here is an example class BaseA ; endclass class DerivedA extends BaseA endclass 1) Set config_db DerivedA a1; a1 = DerivedA::create() uvm_config_db#(DerivedA)::set(this, "" , "myobj", a1); 2) Get config_db BaseA a1; DerivedA a2; uvm_config_db#(BaseA)::get(this, "" , "myobj", a1); $cast(a2, a1);

I need to have two uvm_tlm_target_socket in a class and I need to do different set of things with the data received via two sockets. I was thinking if it is possible to have two implementation of b_transport task. I am aware of how we can have multiple analysis port imp and use uvm_analysis_imp_decl(_something) and we can have a "write_something" implementation. Is something similar available for uvm_tlm_target_socket? Regards, Gautam