Class: Udb::CsrField

Inherits:
DatabaseObject show all
Extended by:
T::Sig
Includes:
Idl::CsrField, CertifiableObject
Defined in:
lib/udb/obj/csr_field.rb

Overview

A CSR field object

Defined Under Namespace

Classes: Alias, MemoizedState

Constant Summary collapse

TYPE_DESC_MAP = 
{
  "RO" =>
    <<~DESC,
  "RO-H" =>
    <<~DESC,
  "RW" =>
    <<~DESC,
  "RW-R" =>
    <<~DESC,
  "RW-H" =>
    <<~DESC,
  "RW-RH" =>
    <<~DESC
    *Read-Write Restricted with Hardware update*

    Field is writable by software.
    Only certain values are legal.
    Writing an illegal value into the field is ignored, such that the field retains its prior state.
    Hardware also updates the field without an explicit software write.)
  DESC
}.freeze

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(parent_csr, field_name, field_data)

Parameters:

  • parent_csr (Csr) —

    The Csr that defined this field

  • field_name (String)
  • field_data (Hash{String => T.untyped}) —

    Field data from the arch spec



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# File 'lib/udb/obj/csr_field.rb', line 57

def initialize(parent_csr, field_name, field_data)
  super(field_data, parent_csr.data_path, parent_csr.arch, DatabaseObject::Kind::CsrField, name: field_name)
  @parent = parent_csr
  @memo = MemoizedState.new(reachable_functions: {})
end

Instance Attribute Details

#parent ⇒ Csr (readonly) Also known as: csr

Returns The Csr that defines this field.

Returns:

  • (Csr) —

    The Csr that defines this field



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# File 'lib/udb/obj/csr_field.rb', line 26

def parent
  @parent
end

Instance Method Details

#__source ⇒ Object

CSR fields are defined in their parent CSR YAML file



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# File 'lib/udb/obj/csr_field.rb', line 64

def __source = @parent.__source

#affected_by?(ext_ver) ⇒ Boolean

Returns Whether or not the presence of ext_ver affects this CSR Field definition This does not take the parent CSR into account, i.e., a field can be unaffected by ext_ver even if the parent CSR is affected.

Parameters:

Returns:

  • (Boolean) —

    Whether or not the presence of ext_ver affects this CSR Field definition This does not take the parent CSR into account, i.e., a field can be unaffected by ext_ver even if the parent CSR is affected



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# File 'lib/udb/obj/csr_field.rb', line 109

def affected_by?(ext_ver)
  defined_by_condition.empty? \
    ? false
    : defined_by_condition.satisfiability_depends_on_ext_req?(ext_ver.to_ext_req)
end

#alias ⇒ Alias?

Returns The aliased field, or nil if there is no alias.

Returns:

  • (Alias, nil) —

    The aliased field, or nil if there is no alias



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# File 'lib/udb/obj/csr_field.rb', line 282

def alias
  return @alias unless @alias.nil?

  if @data.key?("alias")
    raise "Can't parse alias" unless data["alias"] =~ /^[a-z][a-z0-9]+\.[A-Z0-9]+(\[([0-9]+)(:[0-9]+)?\])?$/

    csr_name = T.must(Regexp.last_match(1))
    csr_field = Regexp.last_match(2)
    range = Regexp.last_match(3)
    range_start = Regexp.last_match(4)
    range_end = Regexp.last_match(5)

    csr_field = T.must(cfg_arch.csr(csr_name)).field(csr_field)
    range =
      if range.nil?
        csr_field.location
      elsif range_end.nil?
        (range_start.to_i..range_start.to_i)
      else
        (range_start.to_i..range_end[1..].to_i)
      end
    @alias = Alias.new(csr_field, range)
  end
  @alias
end

#base ⇒ nil, Integer

Returns:

  • (nil) —

    if the CsrField exists in any XLEN

  • (Integer, nil) —

    The base XLEN required for this CsrField to exist. One of [32, 64]



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# File 'lib/udb/obj/csr_field.rb', line 37

def base
  return @base if defined?(@base)

  @base =
    if defined_by_condition.rv32_only?
      32
    elsif defined_by_condition.rv64_only?
      64
    else
      nil
    end
end

#base32_only? ⇒ Boolean

Returns Whether or not this field only exists when XLEN == 32.

Returns:

  • (Boolean) —

    Whether or not this field only exists when XLEN == 32



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# File 'lib/udb/obj/csr_field.rb', line 695

def base32_only? = base == 32

#base64_only? ⇒ Boolean

Returns Whether or not this field only exists when XLEN == 64.

Returns:

  • (Boolean) —

    Whether or not this field only exists when XLEN == 64



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# File 'lib/udb/obj/csr_field.rb', line 691

def base64_only? = base == 64

#cert_coverage_point(id) ⇒ CertNormativeRule? Originally defined in module CertifiableObject

Parameters:

  • id (String) —

    Unique ID for the normative rule

Returns:

  • (CertNormativeRule)
  • (nil) —

    if there is no certification normative ruleed with ID of id

#cert_coverage_point_hash ⇒ Hash<String, CertNormativeRule> Originally defined in module CertifiableObject

Returns Hash with ID as key of all normative rules defined by database object.

Returns:

  • (Hash<String, CertNormativeRule>) —

    Hash with ID as key of all normative rules defined by database object

#cert_normative_rules ⇒ Array<CertNormativeRule> Originally defined in module CertifiableObject

Returns:

#cert_test_procedure(id) ⇒ CertTestProcedure? Originally defined in module CertifiableObject

Parameters:

  • id (String) —

    Unique ID for test procedure

Returns:

  • (CertTestProcedure)
  • (nil) —

    if there is no certification test procedure with ID id

#cert_test_procedure_hash ⇒ Hash<String, CertTestProcedure> Originally defined in module CertifiableObject

Returns Hash of all normative rules defined by database object.

Returns:

  • (Hash<String, CertTestProcedure>) —

    Hash of all normative rules defined by database object

#cert_test_procedures ⇒ Array<CertTestProcedure> Originally defined in module CertifiableObject

Returns:

#defined_in_all_bases? ⇒ Boolean

Returns Whether or not this field exists for any XLEN.

Returns:

  • (Boolean) —

    Whether or not this field exists for any XLEN



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# File 'lib/udb/obj/csr_field.rb', line 708

def defined_in_all_bases? = base.nil?

#defined_in_base32? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/udb/obj/csr_field.rb', line 698

def defined_in_base32? = base != 64

#defined_in_base64? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/udb/obj/csr_field.rb', line 701

def defined_in_base64? = base != 32

#defined_in_base?(xlen) ⇒ Boolean

Parameters:

  • xlen (Integer)

Returns:

  • (Boolean) 


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# File 'lib/udb/obj/csr_field.rb', line 704

def defined_in_base?(xlen) = xlen == 32 ? defined_in_base32? : defined_in_base64?

#dynamic_location? ⇒ Boolean

Returns Whether or not the location of the field changes dynamically (e.g., based on mstatus.SXL) in the configuration.

Returns:

  • (Boolean) —

    Whether or not the location of the field changes dynamically (e.g., based on mstatus.SXL) in the configuration



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# File 'lib/udb/obj/csr_field.rb', line 351

def dynamic_location?
  # if there is no location_rv32, the the field never changes
  return false unless @data["location"].nil?

  # the field changes *if* some mode with access can change XLEN
  csr.modes_with_access.any? { |mode| @cfg_arch.multi_xlen_in_mode?(mode) }
end

#dynamic_reset_value? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/udb/obj/csr_field.rb', line 441

def dynamic_reset_value?
  return false unless @data["reset_value"].nil?

  Idl::AstNode.value_try do
    reset_value
    false
  end || true
end

#exists? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/udb/obj/csr_field.rb', line 92

def exists? = exists_in_cfg?(cfg_arch)

#exists_in_cfg?(cfg_arch) ⇒ Boolean

For a full config, whether or not the field is implemented For a partial config, whether or the it is possible for the field to be implemented

Parameters:

Returns:

  • (Boolean) —

    True if this field might exist in a config



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# File 'lib/udb/obj/csr_field.rb', line 77

def exists_in_cfg?(cfg_arch)
  if cfg_arch.fully_configured?
    parent.exists_in_cfg?(cfg_arch) &&
      (base.nil? || cfg_arch.possible_xlens.include?(base)) &&
      (defined_by_condition.satisfied_by_cfg_arch?(cfg_arch) == SatisfiedResult::Yes)
  elsif cfg_arch.partially_configured?
    parent.exists_in_cfg?(cfg_arch) &&
      (base.nil? || cfg_arch.possible_xlens.include?(base)) &&
      defined_by_condition.could_be_satisfied_by_cfg_arch?(cfg_arch)
  else
    true
  end
end

#fill_symtab_for_reset(ast) ⇒ Object 



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# File 'lib/udb/obj/csr_field.rb', line 593

def fill_symtab_for_reset(ast)
  symtab = cfg_arch.symtab.global_clone
  symtab.push(ast)

  symtab.add("__expected_return_type", Idl::Type.new(:bits, width: max_width))

  # XLEN at reset is always mxlen
  symtab.add(
    "__effective_xlen",
    Idl::Var.new("__effective_xlen", Idl::Type.new(:bits, width: 6), cfg_arch.mxlen)
  )

  symtab
end

#fill_symtab_for_sw_write(effective_xlen, ast) ⇒ Idl::SymbolTable

Parameters:

Returns:

  • (Idl::SymbolTable) 


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# File 'lib/udb/obj/csr_field.rb', line 533

def fill_symtab_for_sw_write(effective_xlen, ast)
  symtab = cfg_arch.symtab.global_clone
  symtab.push(ast)

  # all CSR instructions are 32-bit
  symtab.add(
    "__instruction_encoding_size",
    Idl::Var.new("__instruction_encoding_size", Idl::Type.new(:bits, width: 6), 32)
  )
  symtab.add(
    "__expected_return_type",
    Idl::Type.new(:bits, width: 128)
  )
  symtab.add(
    "csr_value",
    Idl::Var.new("csr_value", csr.bitfield_type(@cfg_arch, effective_xlen))
  )
  if symtab.get("MXLEN").value.nil?
    symtab.add(
      "MXLEN",
      Idl::Var.new(
        "MXLEN",
        Idl::Type.new(:bits, width: 6, qualifiers: [:const]),
        effective_xlen,
        param: true
      )
    )
  end
  symtab
end

#fill_symtab_for_type(effective_xlen, ast) ⇒ Idl::SymbolTable

Parameters:

Returns:

  • (Idl::SymbolTable) 


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# File 'lib/udb/obj/csr_field.rb', line 565

def fill_symtab_for_type(effective_xlen, ast)
  symtab = cfg_arch.symtab.global_clone
  symtab.push(ast)

  # all CSR instructions are 32-bit
  symtab.add(
    "__instruction_encoding_size",
    Idl::Var.new("__instruction_encoding_size", Idl::Type.new(:bits, width: 6), 32)
  )
  symtab.add(
    "__expected_return_type",
    Idl::Type.new(:enum_ref, enum_class: symtab.get("CsrFieldType"))
  )
  if symtab.get("MXLEN").value.nil?
    symtab.add(
      "MXLEN",
      Idl::Var.new(
        "MXLEN",
        Idl::Type.new(:bits, width: 6, qualifiers: [:const]),
        effective_xlen,
        param: true
      )
    )
  end

  symtab
end

#has_custom_sw_write? ⇒ Boolean

Returns true if the CSR field has a custom sw_write function.

Returns:

  • (Boolean) —

    true if the CSR field has a custom sw_write function



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# File 'lib/udb/obj/csr_field.rb', line 465

def has_custom_sw_write?
  @data.key?("sw_write(csr_value)") && !@data["sw_write(csr_value)"].empty?
end

#location(effective_xlen = nil) ⇒ Range<Integer>

Returns the location within the CSR as a range (single bit fields will be a range of size 1).

Parameters:

  • cfg_arch (ConfiguredArchitecture) —

    A config. May be nil if the location is not configturation-dependent

  • effective_xlen (Integer, nil) (defaults to: nil) —

    The effective xlen, needed since some fields change location with XLEN. If the field location is not determined by XLEN, then this parameter can be nil

Returns:

  • (Range<Integer>) —

    the location within the CSR as a range (single bit fields will be a range of size 1)



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# File 'lib/udb/obj/csr_field.rb', line 644

def location(effective_xlen = nil)
  key =
    if @data.key?("location")
      "location"
    else
      raise ArgumentError, "The location of #{csr.name}.#{name} changes with XLEN, so effective_xlen must be provided" unless [32, 64].include?(effective_xlen)

      "location_rv#{effective_xlen}"
    end

  raise "Missing location for #{csr.name}.#{name} (#{key})?" unless @data.key?(key)

  if @data[key].is_a?(Integer)
    csr_length = csr.length(effective_xlen || base)
    if csr_length.nil?
      # we don't know the csr length for sure, so we can only check again max_length
      if @data[key] > csr.max_length
        raise "Location (#{key} = #{@data[key]}) is past the max csr length (#{csr.max_length}) in #{csr.name}.#{name}"
      end
    elsif @data[key] > csr_length
      raise "Location (#{key} = #{@data[key]}) is past the csr length (#{csr.length(effective_xlen)}) in #{csr.name}.#{name}"
    end

    @data[key]..@data[key]
  else
    raise "Unexpected location field" unless @data[key].is_a?(String)

    e, s = @data[key].split("-").map(&:to_i)
    raise "Invalid location" if s > e

    csr_length = csr.length(effective_xlen || base)
    if csr_length.nil?
      # we don't know the csr length for sure, so we can only check again max_length
      if e > csr.max_length
        Udb.logger.warn "Location (#{key} = #{@data[key]}) is past the max csr length (#{csr.max_length}) in #{csr.name}.#{name}"
      end
    elsif e > csr_length
      Udb.logger.warn "Location (#{key} = #{@data[key]}) is past the csr length (#{csr_length}) in #{csr.name}.#{name}"

    end

    s..e
  end
end

#location_cond32 ⇒ String

Returns:

  • (String) 


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# File 'lib/udb/obj/csr_field.rb', line 732

def location_cond32
  case csr.priv_mode
  when "M"
    "CSR[misa].MXL == 0"
  when "S"
    "CSR[mstatus].SXL == 0"
  when "VS"
    "CSR[hstatus].VSXL == 0"
  when "U"
    "CSR[mstatus].UXL == 0"
  else
    raise "Unexpected priv mode #{csr.priv_mode} for #{csr.name}"
  end
end

#location_cond64 ⇒ String

Returns:

  • (String) 


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# File 'lib/udb/obj/csr_field.rb', line 748

def location_cond64
  case csr.priv_mode
  when "M"
    "CSR[misa].MXL == 1"
  when "S"
    "CSR[mstatus].SXL == 1"
  when "VS"
    "CSR[hstatus].VSXL == 1"
  when "U"
    "CSR[mstatus].UXL == 1"
  else
    raise "Unexpected priv mode #{csr.priv_mode} for #{csr.name}"
  end
end

#location_pretty(effective_xlen = nil) ⇒ String

Returns Pretty-printed location string.

Parameters:

  • effective_xlen (Integer, nil) (defaults to: nil) —

    32 or 64 for fixed xlen, nil for dynamic

Returns:

  • (String) —

    Pretty-printed location string



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# File 'lib/udb/obj/csr_field.rb', line 766

def location_pretty(effective_xlen = nil)
  derangeify = proc { |loc|
    next loc.min.to_s if loc.size == 1

    "#{loc.max}:#{loc.min}"
  }

  if dynamic_location?
    condition =
      case csr.priv_mode
      when "M"
        "CSR[misa].MXL == %%"
      when "S"
        "CSR[mstatus].SXL == %%"
      when "VS"
        "CSR[hstatus].VSXL == %%"
      when "U"
        "CSR[mstatus].UXL == %%"
      else
        raise "Unexpected priv mode #{csr.priv_mode} for #{csr.name}"
      end

    if effective_xlen.nil?
      <<~LOC
      * #{derangeify.call(location(32))} when #{condition.sub('%%', '0')}
      * #{derangeify.call(location(64))} when #{condition.sub('%%', '1')}
    LOC
    else
      derangeify.call(location(effective_xlen))
    end
  else
    derangeify.call(location(cfg_arch.mxlen))
  end
end

#max_width ⇒ Integer

Returns:

  • (Integer) 


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# File 'lib/udb/obj/csr_field.rb', line 718

def max_width
  @max_width ||=
    if base64_only?
      cfg_arch.possible_xlens.include?(64) ? width(64) : 0
    elsif base32_only?
      cfg_arch.possible_xlens.include?(32) ? width(32) : 0
    else
      @cfg_arch.possible_xlens.map do |xlen|
        width(xlen)
      end.max
    end
end

#optional_in_cfg?(cfg_arch) ⇒ Boolean

Returns For a partially configured cfg_arch, whether or not the field is optional (not mandatory or prohibited).

Parameters:

Returns:

  • (Boolean) —

    For a partially configured cfg_arch, whether or not the field is optional (not mandatory or prohibited)



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# File 'lib/udb/obj/csr_field.rb', line 96

def optional_in_cfg?(cfg_arch)
  raise "optional_in_cfg? should only be called on a partially configured cfg_arch" unless cfg_arch.partially_configured?

  exists_in_cfg?(cfg_arch) &&
    defined_by_condition.empty? \
      ? parent.optional_in_cfg?(cfg_arch)
      : (defined_by_condition.satisfied_by_cfg_arch?(cfg_arch) == SatisfiedResult::Maybe)
end

#pruned_reset_value_ast ⇒ nil, Idl::FunctionBodyAst

Returns:

  • (nil) —

    If the reset_value is not a function

  • (Idl::FunctionBodyAst, nil) —

    Abstract syntax tree of the reset_value function, type checked and pruned



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# File 'lib/udb/obj/csr_field.rb', line 401

def pruned_reset_value_ast
  return @pruned_reset_value_ast unless @pruned_reset_value_ast.nil?

  return nil unless @data.key?("reset_value()")

  ast = T.must(type_checked_reset_value_ast)

  symtab = fill_symtab_for_reset(ast)
  ast = ast.prune(symtab)
  symtab.pop
  ast.freeze_tree(symtab)
  symtab.release

  @pruned_reset_value_ast = ast
end

#pruned_sw_write_ast(effective_xlen) ⇒ nil, Idl::AstNode

Parameters:

  • effective_xlen (Integer, nil) —

    effective xlen, needed because fields can change in different bases

Returns:

  • (nil) —

    if there is no sw_write() function

  • (Idl::AstNode, nil) —

    The abstract syntax tree of the sw_write() function, type checked and pruned



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# File 'lib/udb/obj/csr_field.rb', line 612

def pruned_sw_write_ast(effective_xlen)
  return @pruned_sw_write_ast unless @pruned_sw_write_ast.nil?

  return nil unless @data.key?("sw_write(csr_value)")

  ast = T.must(type_checked_sw_write_ast(cfg_arch.symtab, effective_xlen))

  return ast if cfg_arch.unconfigured?

  symtab = fill_symtab_for_sw_write(effective_xlen, ast)

  ast = ast.prune(symtab)
  raise "Symbol table didn't come back at global + 1" unless symtab.levels == 2

  ast.freeze_tree(cfg_arch.symtab)

  cfg_arch.idl_compiler.type_check(
    ast,
    symtab,
    "CSR[#{name}].sw_write(csr_value)"
  )

  symtab.pop
  symtab.release

  @pruned_sw_write_ast = ast
end

#pruned_type_ast(effective_xlen) ⇒ nil, Idl::FunctionBodyAst

Parameters:

  • effective_xlen (Integer, nil) —

    The effective xlen to evaluate for

Returns:

  • (nil) —

    if the type property is not a function

  • (Idl::FunctionBodyAst, nil) —

    Abstract syntax tree of the type() function, after it has been type checked and pruned



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# File 'lib/udb/obj/csr_field.rb', line 173

def pruned_type_ast(effective_xlen)
  @pruned_type_ast ||= { 32 => nil, 64 => nil }
  return @pruned_type_ast[effective_xlen] unless @pruned_type_ast[effective_xlen].nil?

  ast = type_checked_type_ast(effective_xlen)

  if ast.nil?
    # there is no type() (it must be constant)
    return nil
  end

  symtab = fill_symtab_for_type(effective_xlen, ast)
  ast = ast.prune(symtab)
  symtab.release

  symtab = fill_symtab_for_type(effective_xlen, ast)
  ast.freeze_tree(symtab)

  @cfg_arch.idl_compiler.type_check(
    ast,
    symtab,
    "CSR[#{name}].type()"
  )

  symtab.pop
  symtab.release

  @pruned_type_ast[effective_xlen] = ast
end

#reachable_functions(effective_xlen) ⇒ Array<Idl::FunctionDefAst>

Returns List of functions called through this field.

Parameters:

Returns:

  • (Array<Idl::FunctionDefAst>) —

    List of functions called through this field



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# File 'lib/udb/obj/csr_field.rb', line 312

def reachable_functions(effective_xlen)
  cache_key = effective_xlen.nil? ? :nil : effective_xlen
  return @memo.reachable_functions[cache_key] unless @memo.reachable_functions[cache_key].nil?

  fns = []
  if has_custom_sw_write?
    ast = pruned_sw_write_ast(effective_xlen)
    unless ast.nil?
      sw_write_symtab = fill_symtab_for_sw_write(effective_xlen, ast)
      fns.concat ast.reachable_functions(sw_write_symtab)
      sw_write_symtab.release
    end
  end
  if @data.key?("type()")
    ast = pruned_type_ast(effective_xlen)
    unless ast.nil?
      type_symtab = fill_symtab_for_type(effective_xlen, ast)
      fns.concat ast.reachable_functions(type_symtab)
      type_symtab.release
    end
  end
  if @data.key?("reset_value()")
    ast = pruned_reset_value_ast
    unless ast.nil?
      symtab = fill_symtab_for_reset(ast)
      fns.concat ast.reachable_functions(symtab)
      symtab.release
    end
  end

  @memo.reachable_functions[cache_key] = fns.uniq
end

#reset_value ⇒ String, Idl::ValueRbType

Returns:

  • (String) —

    The string ‘UNDEFINED_LEGAL’ if, for this config, there is no defined reset value

  • (Idl::ValueRbType) —

    The reset value of this field



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# File 'lib/udb/obj/csr_field.rb', line 420

def reset_value
  @reset_value ||=
    if @data.key?("reset_value")
      @data["reset_value"]
    else
      ast = T.must(pruned_reset_value_ast)
      symtab = fill_symtab_for_reset(ast)
      val = T.let(nil, T.untyped)
      value_result = Idl::AstNode.value_try do
        val = ast.return_value(symtab)
      end
      Idl::AstNode.value_else(value_result) do
        val = "UNDEFINED_LEGAL"
      end
      val = "UNDEFINED_LEGAL" if val == 0x1_0000_0000_0000_0000
      symtab.release
      val
    end
end

#reset_value_ast ⇒ nil, Idl::FunctionBodyAst

Returns:

  • (nil) —

    If the reset_value is not a function

  • (Idl::FunctionBodyAst, nil) —

    Abstract syntax tree of the reset_value function



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# File 'lib/udb/obj/csr_field.rb', line 362

def reset_value_ast
  return @reset_value_ast unless @reset_value_ast.nil?
  return nil unless @data.key?("reset_value()")

  @reset_value_ast = cfg_arch.idl_compiler.compile_func_body(
    @data["reset_value()"],
    return_type: Idl::Type.new(:bits, width: max_width),
    name: "CSR[#{parent.name}].#{name}.reset_value()",
    input_file: csr.__source,
    input_line: csr.source_line(["fields", name, "reset_value()"]),
    symtab: cfg_arch.symtab,
    type_check: false
  )
end

#reset_value_pretty ⇒ String

Returns:

  • (String) 


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# File 'lib/udb/obj/csr_field.rb', line 451

def reset_value_pretty
  str = T.let(nil, T.nilable(Idl::ValueRbType))
  value_result = Idl::AstNode.value_try do
    str = reset_value
  end
  Idl::AstNode.value_else(value_result) do
    ast = T.must(reset_value_ast)
    str = ast.gen_option_adoc
  end
  T.must(str).to_s
end

#source_line(path) ⇒ Integer

CSR field data starts at fields: NAME: with the YAML

Parameters:

  • path (Array<String, Integer>)

Returns:

  • (Integer) 


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# File 'lib/udb/obj/csr_field.rb', line 68

def source_line(path)
  super(["fields", name].concat(path))
end

#sw_write_ast(symtab) ⇒ nil, Idl::FunctionBodyAst

Parameters:

  • symtab (Idl::SymbolTable) —

    Symbols

Returns:

  • (nil) —

    If there is no sw_write() function

  • (Idl::FunctionBodyAst, nil) —

    The abstract syntax tree of the sw_write() function



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# File 'lib/udb/obj/csr_field.rb', line 512

def sw_write_ast(symtab)
  return @sw_write_ast unless @sw_write_ast.nil?
  return nil if @data["sw_write(csr_value)"].nil?

  # now, parse the function
  @sw_write_ast = @cfg_arch.idl_compiler.compile_func_body(
    @data["sw_write(csr_value)"],
    return_type: Idl::Type.new(:bits, width: 128), # big int to hold special return values
    name: "CSR[#{csr.name}].#{name}.sw_write(csr_value)",
    input_file: csr.__source,
    input_line: csr.source_line(["fields", name, "sw_write(csr_value)"]),
    symtab:,
    type_check: false
  )

  raise "unexpected #{@sw_write_ast.class}" unless @sw_write_ast.is_a?(Idl::FunctionBodyAst)

  @sw_write_ast
end

#type(effective_xlen = nil) ⇒ nil, String

returns the definitive type for a configuration

Parameters:

  • effective_xlen (Integer, nil) (defaults to: nil) —

    The effective xlen to evaluate for

Returns:

  • (nil) —

    when the type isn’t knowable

  • (String, nil) —

    The type of the field. One of: ‘RO’ => Read-only ‘RO-H’ => Read-only, with hardware update ‘RW’ => Read-write ‘RW-R’ => Read-write, with a restricted set of legal values ‘RW-H’ => Read-write, with a hardware update ‘RW-RH’ => Read-write, with a hardware update and a restricted set of legal values



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# File 'lib/udb/obj/csr_field.rb', line 216

def type(effective_xlen = nil)
  @type ||= { 32 => nil, 64 => nil }
  return @type[effective_xlen] unless @type[effective_xlen].nil?

  type = T.let(nil, T.untyped)
  type =
    if @data.key?("type")
      @data["type"]
    else
      # the type is config-specific...

      ast = T.must(type_checked_type_ast(effective_xlen))
      begin
        symtab = fill_symtab_for_type(effective_xlen, ast)

        value_result = ast.value_try do
          type =  case ast.return_value(symtab)
                  when 0
                    "RO"
                  when 1
                    "RO-H"
                  when 2
                    "RW"
                  when 3
                    "RW-R"
                  when 4
                    "RW-H"
                  when 5
                    "RW-RH"
                  else
                    raise "Unhandled CsrFieldType value"
                  end
        end
        ast.value_else(value_result) do
          type = nil
        end
      ensure
        symtab&.pop
        symtab&.release
      end
      type
      # end
      # Idl::AstNode.value_else(value_result) do
      #   warn "In parsing #{csr.name}.#{name}::type()"
      #   raise "  Return of type() function cannot be evaluated at compile time"
      #   Idl::AstNode.value_error ""
      # end
    end

  @type[effective_xlen] = type
end

#type_ast ⇒ nil, Idl::FunctionBodyAst

Returns:

  • (nil) —

    if the type property is not a function

  • (Idl::FunctionBodyAst, nil) —

    Abstract syntax tree of the type() function



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# File 'lib/udb/obj/csr_field.rb', line 118

def type_ast
  return @type_ast unless @type_ast.nil?
  return nil if @data["type()"].nil?

  idl_code = T.must(@data["type()"])

  @type_ast = @cfg_arch.idl_compiler.compile_func_body(
    idl_code,
    name: "CSR[#{csr.name}].#{name}.type()",
    input_file: csr.__source,
    input_line: csr.source_line(["fields", name, "type()"]),
    symtab: @cfg_arch.symtab,
    type_check: false
  )

  raise "ast is nil?" if @type_ast.nil?

  raise "unexpected #{@type_ast.class}" unless @type_ast.is_a?(Idl::FunctionBodyAst)

  @type_ast
end

#type_checked_reset_value_ast ⇒ nil, Idl::FunctionBodyAst

Returns:

  • (nil) —

    If the reset_value is not a function

  • (Idl::FunctionBodyAst, nil) —

    Abstract syntax tree of the reset_value function, after being type checked



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# File 'lib/udb/obj/csr_field.rb', line 380

def type_checked_reset_value_ast
  return @type_checked_reset_value_ast unless @type_checked_reset_value_ast.nil?

  return nil unless @data.key?("reset_value()")

  ast = reset_value_ast

  symtab = fill_symtab_for_reset(ast)
  cfg_arch.idl_compiler.type_check(
    ast,
    symtab,
    "CSR[#{csr.name}].reset_value()"
  )
  symtab.release

  @type_checked_reset_value_ast = ast
end

#type_checked_sw_write_ast(symtab, effective_xlen) ⇒ Idl::FunctionBodyAst?

Returns The abstract syntax tree of the sw_write() function, after being type checked.

Parameters:

  • symtab (Idl::SymbolTable) —

    Symbol table with globals

  • effective_xlen (Integer, nil) —

    32 or 64; the effective XLEN to evaluate this field in (relevant when fields move in different XLENs)

Returns:

  • (Idl::FunctionBodyAst, nil) —

    The abstract syntax tree of the sw_write() function, after being type checked



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# File 'lib/udb/obj/csr_field.rb', line 473

def type_checked_sw_write_ast(symtab, effective_xlen)
  @type_checked_sw_write_asts ||= {}
  ast = @type_checked_sw_write_asts[symtab.hash]
  return ast unless ast.nil?

  return nil unless @data.key?("sw_write(csr_value)")

  symtab_hash = symtab.hash
  symtab = symtab.global_clone
  symtab.push(ast)
  # all CSR instructions are 32-bit
  symtab.add(
    "__instruction_encoding_size",
    Idl::Var.new("__instruction_encoding_size", Idl::Type.new(:bits, width: 6), 32)
  )
  symtab.add(
    "__expected_return_type",
    Idl::Type.new(:bits, width: 128) # to accommodate special return values (e.g., UNDEFIEND_LEGAL_DETERMINISITIC)
  )
  symtab.add(
    "csr_value",
    Idl::Var.new("csr_value", csr.bitfield_type(@cfg_arch, effective_xlen))
  )

  ast = T.must(sw_write_ast(symtab))
  @cfg_arch.idl_compiler.type_check(
    ast,
    symtab,
    "CSR[#{csr.name}].#{name}.sw_write()"
  )
  symtab.pop
  symtab.release
  @type_checked_sw_write_asts[symtab_hash] = ast
end

#type_checked_type_ast(effective_xlen) ⇒ nil, Idl::FunctionBodyAst

Parameters:

  • effective_xlen (Integer, nil) —

    The effective xlen to evaluate for

Returns:

  • (nil) —

    if the type property is not a function

  • (Idl::FunctionBodyAst, nil) —

    Abstract syntax tree of the type() function, after it has been type checked



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# File 'lib/udb/obj/csr_field.rb', line 144

def type_checked_type_ast(effective_xlen)
  @type_checked_type_ast ||= { 32 => nil, 64 => nil }
  return @type_checked_type_ast[effective_xlen] unless @type_checked_type_ast[effective_xlen].nil?

  ast = type_ast

  if ast.nil?
    # there is no type() (it must be constant)
    return nil
  end

  symtab = fill_symtab_for_type(effective_xlen, ast)

  cfg_arch.idl_compiler.type_check(
    ast,
    symtab,
    "CSR[#{name}].type()"
  )

  symtab.pop
  symtab.release

  @type_checked_type_ast[effective_xlen] = ast
end

#type_desc(effective_xlen = nil) ⇒ String

Returns Long description of the field type.

Parameters:

  • effective_xlen (Integer, nil) (defaults to: nil)

Returns:

  • (String) —

    Long description of the field type



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# File 'lib/udb/obj/csr_field.rb', line 852

def type_desc(effective_xlen = nil)
  TYPE_DESC_MAP.fetch(type(effective_xlen), "")
end

#type_pretty(effective_xlen = nil) ⇒ String

Returns A pretty-printed type string.

Parameters:

  • effective_xlen (Integer, nil) (defaults to: nil) —

    The effective xlen to evaluate for

Returns:

  • (String) —

    A pretty-printed type string



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# File 'lib/udb/obj/csr_field.rb', line 271

def type_pretty(effective_xlen = nil)
  str = type(effective_xlen)
  if str.nil?
    ast = T.must(type_ast)
    str = ast.gen_option_adoc
  end
  T.must(str)
end

#width(effective_xlen) ⇒ Integer

Returns Number of bits in the field.

Parameters:

  • effective_xlen (Integer, nil) —

    The effective xlen, needed since some fields change location with XLEN. If the field location is not determined by XLEN, then this parameter can be nil

Returns:

  • (Integer) —

    Number of bits in the field



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# File 'lib/udb/obj/csr_field.rb', line 713

def width(effective_xlen)
  T.must(location(effective_xlen).size)
end