extract CSR numbers

[ThinkOpenly]

Thanks to 7738de1, we are extracting register names and types:

  "registers": [ 
    { "name": "mcounteren", "type": "Counteren" },
    { "name": "scounteren", "type": "Counteren" },
    { "name": "mcountinhibit", "type": "Counterin" },
    { "name": "fcsr", "type": "Fcsr" },

Some of the "special registers" are associated with a number. In model/riscv_csr_map.sail:

mapping clause csr_name_map = 0x306  <-> "mcounteren"
mapping clause csr_name_map = 0x106  <-> "scounteren"
mapping clause csr_name_map = 0x320  <-> "mcountinhibit"
mapping clause csr_name_map = 0x003  <-> "fcsr"

We should extract these numbers and add them to their respective register data.

[aryansharma6827]

hi i am Aryan Sharma currently learning this codebase i would like to work in this issue please assign it to me.

[ThinkOpenly]

I have assigned you, @aryansharma6827 , but please ask questions and I'll ask that you provide occasional updates on progress. If you do feel that you will be unwilling or unable to continue, I ask that you let me know.

[aryansharma6827]

can you please elaborate the issue and how to proceed further.

[ThinkOpenly]

We now emit the following in the JSON output:

  "registers": [ 
    { "name": "mcounteren", "type": "Counteren" },
    { "name": "scounteren", "type": "Counteren" },
    { "name": "mcountinhibit", "type": "Counterin" },
    { "name": "fcsr", "type": "Fcsr" },
[...]

There is additional information (the associated register numbers for CSRs) that should be included. The information can be found in model/riscv_csr_map.sail:

mapping clause csr_name_map = 0x306  <-> "mcounteren"
mapping clause csr_name_map = 0x106  <-> "scounteren"
mapping clause csr_name_map = 0x320  <-> "mcountinhibit"
mapping clause csr_name_map = 0x003  <-> "fcsr"
[...]

So, the resulting JSON should be enhanced to include this additional information:

  "registers": [ 
    { "name": "mcounteren", "type": "Counteren", "number": "0x306" },
    { "name": "scounteren", "type": "Counteren", "number": "0x106" },
    { "name": "mcountinhibit", "type": "Counterin", "number": "0x320" },
    { "name": "fcsr", "type": "Fcsr", "number": "0x003" },
[...]

This additional information is encoded in a scattered mapping as a series of mapping clause statements. mapping clause AST elements are handled (in src/sail_json_backend/json.ml) in parse_mapcl. You can see stanzas for handling "encdec" and "assembly" mapping clause statements. The work for this issue would entail adding another stanza for "csr_name_map" clauses, storing the number as the value associated with a key which would be the register name.

The other part of the work is adding the "number" field when emitting the registers as JSON. This would entail enhancements to json_of_registers.

I hope that helps.

[Abhivic000]

Hi, I'm Abhishek Singh. I'm currently working on this issue and have identified the necessary changes. If the assignee is unable to continue, please reassign it to me.