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Register field access issue

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I got a issue when I want to do byte enable access in my register.

My register model is 64bits width and it has several fields inside as following:

class reg_reg_R extends uvm_reg;

rand uvm_reg_field F1;

rand uvm_reg_field F2;

rand uvm_reg_field F3;

rand uvm_reg_field F4;

function new(string name = "R");

super.new(name, 64, UVM_NO_COVERAGE);

endfunction: new

virtual function void build();

this.F1 = uvm_reg_field::type_id::create("F1");

this.F1.configure(this, 8, 0, "RW", 0, 8'h0, 1, 0, 1);

this.F2 = uvm_reg_field::type_id::create("F2");

this.F2.configure(this, 8, 16, "RW", 0, 8'h0, 1, 0, 1);

this.F3 = uvm_reg_field::type_id::create("F3");

this.F3.configure(this, 8, 24, "RW", 0, 8'h0, 1, 0, 1);

this.F4 = uvm_reg_field::type_id::create("F4");

this.F4.configure(this, 8, 56, "RW", 0, 8'h0, 1, 0, 1);

endfunction: build


endclass : reg_reg_R

My register map access width in 1 byte

APB = create_map("APB", 'h0, 1, UVM_LITTLE_ENDIAN);

default_map = APB;

rand reg_reg_R A;

APB.add_reg(A, 'h0, "RW");

I also set register layer adapter "supports_byte_enable = 1" to allow byte access.

my sequence only send 1 write request to register field F3.

model.A.F3.write(status, 'h33, .parent(this));

From result I found not only field "F3" (byte 3) has been written with data 'h33, byte 4, byte5, byte6, byte7 also have been written with data 'h0. And function "reg2bus" inside register adapter has been called 5 times not only once.

How can I do specific byte operation in register w/o accessing other fields?


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