Add concept of partially configured arch def

arch/csr/misa.yaml

@@ -4,12 +4,13 @@ misa:
   long_name: Machine ISA Control
   address: 0x301
   priv_mode: M
-  length: 64
+  length: MXLEN
   description: Reports the XLEN and "major" extensions supported by the ISA.
   definedBy: Sm
   fields:
     MXL:
-      location: 63-62
+      location_rv32: 31-30
+      location_rv64: 63-62
       description: XLEN in M-mode.
       type: RO
       reset_value: 2

arch/csr/mstatus.yaml

@@ -241,9 +241,29 @@ mstatus:
         *`hfence.vvma`, `sfence.w.inval`, or `sfence.inval.ir` to trap.
         * Any additional traps in VS-mode (controlled via `hstatus.VTVM` instead).
 
-      type: RW
+      type(): |
+        if (CSR[misa].S == 1'b0) {
+          return CsrFieldType::RO;
+        } else {
+          return CsrFieldType::RW;
+        }
       definedBy: S
-      reset_value: UNDEFINED_LEGAL
+      reset_value(): |
+        if (CSR[misa].S == 1'b0) {
+          return 0;
+        } else if (MSTATUS_TVM_IMPLEMENTED) {
+          return UNDEFINED_LEGAL;
+        } else {
+          return 0;
+        }
+      sw_write(csr_value): |
+        if (CSR[misa].S == 1'b0) {
+          return 0;
+        } else if (MSTATUS_TVM_IMPLEMENTED) {
+          return csr_value.TVM;
+        } else {
+          return 0;
+        }
     MXR:
       location: 19
       description: |
@@ -286,7 +306,8 @@ mstatus:
 
         `mstatus.MPRV` is cleared on any exception return (`mret` or `sret` instruction, regardless of the trap handler privilege mode).
       definedBy: U
-      type: RW-H
+      type(): |
+        return (CSR[misa].U == 1'b1) ? CsrFieldType::RWH : CsrFieldType::RO;
       reset_value: 0
     XS:
       location: 16-15
@@ -308,9 +329,37 @@ mstatus:
         When a floating point register, or the fCSR register is written, FS obtains the value 3.
         Values 1 and 2 are valid write values for software, but are not interpreted by hardware
         other than to possibly enable a previously-disabled floating point unit. 
-      type: RW-H
+      type(): |
+        if (CSR[misa].F == 1'b1){
+          return CsrFieldType::RWH;
+        } else if ((CSR[misa].S == 1'b0) && (CSR[misa].F == 1'b0)) {
+          # must be read-only-0
+          return CsrFieldType::RO;
+        } else {
+          # there will be no hardware update in this case because we know the F extension isn't implemented
+          return MSTATUS_FS_WRITEABLE ? CsrFieldType::RW : CsrFieldType::RO;
+        }
       definedBy: F
-      reset_value: UNDEFINED_LEGAL
+      reset_value(): |
+        if (CSR[misa].F == 1'b1){
+          return UNDEFINED_LEGAL;
+        } else if ((CSR[misa].S == 1'b0) && (CSR[misa].F == 1'b0)) {
+          # must be read-only-0
+          return 0;
+        } else {
+          # there will be no hardware update in this case because we know the F extension isn't implemented
+          return MSTATUS_FS_WRITEABLE ? UNDEFINED_LEGAL : 0;
+        }
+      sw_write(csr_value): |
+        if (CSR[misa].F == 1'b1){
+          return ary_includes?<$array_size(MSTATUS_FS_LEGAL_VALUES), 2>(MSTATUS_FS_LEGAL_VALUES, csr_value.FS) ? csr_value.FS : UNDEFINED_LEGAL_DETERMINISTIC;
+        } else if ((CSR[misa].S == 1'b0) && (CSR[misa].F == 1'b0)) {
+          # must be read-only-0
+          return 0;
+        } else {
+          # there will be no hardware update in this case because we know the F extension isn't implemented
+          return ary_includes?<$array_size(MSTATUS_FS_LEGAL_VALUES), 2>(MSTATUS_FS_LEGAL_VALUES, csr_value.FS) ? csr_value.FS : UNDEFINED_LEGAL_DETERMINISTIC;
+        }
     MPP:
       location: 12-11
       description: |
@@ -449,9 +498,11 @@ mstatus:
         Can also be written by software without immediate side effect.
 
         Other than serving as a record of nested traps as described above, `mstatus.SPIE` does not affect execution.
-      type: RW-H
+      type(): |
+        return (CSR[misa].S == 1'b1) ? CsrFieldType::RWH : CsrFieldType::RO;
       definedBy: S
-      reset_value: UNDEFINED_LEGAL
+      reset_value(): |
+        return (CSR[misa].S == 1'b1) ? UNDEFINED_LEGAL : 0;
     MIE:
       location: 3
       description: |
@@ -484,6 +535,8 @@ mstatus:
         * When 0, all (H)S-mode interrupts are disabled when the current privilege level is (H)S (M-mode interrupts are still enabled).
         * When 1, (H)S-mode interrupts that are not otherwise disabled with a field in `sie` are enabled.
 
-      type: RW-H
+      type(): |
+        return (CSR[misa].S == 1'b1) ? CsrFieldType::RWH : CsrFieldType::RO;
       definedBy: S
-      reset_value: UNDEFINED_LEGAL
+      reset_value(): |
+        return (CSR[misa].S == 1'b1) ? UNDEFINED_LEGAL : 0;

arch/ext/F.yaml

@@ -238,4 +238,17 @@ F:
       description: |
         Indicates whether or not the `F` extension can be disabled with the `misa.F` bit.
       schema:
-        type: boolean
+        type: boolean
+    MSTATUS_FS_LEGAL_VALUES:
+      description: |
+        The set of values that mstatus.FS will accept from a software write.
+      schema:
+        type: array
+        items:
+          type: integer
+          enum: [0,1,2,3]
+        maxItems: 4
+        uniqueItems: true
+      also_defined_in: S
+      extra_validation: |
+        assert MSTATUS_FS_LEGAL_VALUES.include?(0) && MSTATUS_FS_LEGAL_VALUES.include?(3) if ext?(:F)

arch/ext/S.yaml

@@ -242,4 +242,33 @@ S:
         type: boolean
         default: false
       extra_validation:
-        assert TRAP_ON_SFENCE_VMA_WHEN_SATP_MODE_IS_READ_ONLY == false if ext?(:Sv32) || ext?(:Sv39) || ext?(:Sv48) || ext?(:Sv57)
+        assert TRAP_ON_SFENCE_VMA_WHEN_SATP_MODE_IS_READ_ONLY == false if ext?(:Sv32) || ext?(:Sv39) || ext?(:Sv48) || ext?(:Sv57)
+    MSTATUS_FS_WRITEABLE:
+      description: |
+        When `S` is enabled but `F` is not, mstatus.FS is optionally writeable.
+
+        This parameter only has an effect when both S and F mode are disabled.
+      schema:
+        type: boolean
+      extra_validation:
+        assert MSTATUS_FS_WRITEABLE == true if ext?(:F)
+    MSTATUS_FS_LEGAL_VALUES:
+      description: |
+        The set of values that mstatus.FS will accept from a software write.
+      schema:
+        type: array
+        items:
+          type: integer
+          enum: [0,1,2,3]
+        maxItems: 4
+        uniqueItems: true
+      also_defined_in: F
+      extra_validation: |
+        assert MSTATUS_FS_LEGAL_VALUES.include?(0) && MSTATUS_FS_LEGAL_VALUES.include?(3) if ext?(:F)
+    MSTATUS_TVM_IMPLEMENTED:
+      description: |
+        Whether or not mstatus.TVM is implemented.
+
+        When not implemented mstatus.TVM will be read-only-zero.
+      schema:
+        type: boolean

arch/ext/Svade.yaml

@@ -33,7 +33,7 @@ Svade:
     - name: Paul Donahue
     - name: Ved Shanbhogue
       company: Rivos, Inc.
-    conflicts: Svadu
+  conflicts: Svadu
   doc_license:
     name: Creative Commons Attribution 4.0 International License (CC-BY 4.0)
     url: https://creativecommons.org/licenses/by/4.0/

arch/ext/Svadu.yaml

@@ -116,7 +116,7 @@ Svadu:
     - name: Paul Donahue
     - name: Ved Shanbhogue
       company: Rivos, Inc.
-    conflicts: Svade
+  conflicts: Svade
   doc_license:
     name: Creative Commons Attribution 4.0 International License (CC-BY 4.0)
     url: https://creativecommons.org/licenses/by/4.0/

backends/arch_gen/lib/arch_gen.rb

@@ -278,6 +278,7 @@ def gen_arch_def
     end.to_h
 
     arch_def = {
+      "type" => "fully configured",
       "params" => params,
       "instructions" => inst_hash,
       "implemented_instructions" => @implemented_instructions,

backends/arch_gen/tasks.rake

@@ -13,9 +13,13 @@ def arch_def_for(config_name)
 
   @arch_defs[config_name] =
     if config_name == "_"
-      ArchDef.new
+      ArchDef.new("_", $root / "gen" / "_" / "arch" / "arch_def.yaml")
     else
-      ImplArchDef.new(config_name)
+      ArchDef.new(
+        config_name,
+        $root / "gen" / config_name / "arch" / "arch_def.yaml",
+        overlay_path: $root / "cfgs" / config_name / "arch_overlay"
+      )
     end
 end
 
@@ -103,6 +107,7 @@ file "#{$root}/.stamps/arch-gen.stamp" => (
   end.to_h
 
   arch_def = {
+    "type" => "unconfigured",
     "instructions" => inst_hash,
     "extensions" => ext_hash,
     "csrs" => csr_hash,

backends/cfg_html_doc/templates/csr.adoc.erb

@@ -29,7 +29,7 @@ h| Privilege Mode | <%= csr.priv_mode %>
 .<%= csr.name %> format
 [wavedrom, ,svg,subs='attributes',width="100%"]
 ....
-<%= JSON.dump csr.wavedrom_desc(arch_def, arch_def.param_values["XLEN"]) %>
+<%= JSON.dump csr.wavedrom_desc(arch_def, arch_def.param_values["XLEN"], exclude_unimplemented: true) %>
 ....
 <%- else -%>
 <%# CSR has a dynamic length, or a field has a dynamic location,
@@ -39,13 +39,13 @@ This CSR format changes dynamically.
 .<%= csr.name %> Format when <%= csr.length_cond32 %>
 [wavedrom, ,svg,subs='attributes',width="100%"]
 ....
-<%= JSON.dump csr.wavedrom_desc(arch_def, 32) %>
+<%= JSON.dump csr.wavedrom_desc(arch_def, 32, exclude_unimplemented: true) %>
 ....
 
 .<%= csr.name %> Format when <%= csr.length_cond64 %>
 [wavedrom, ,svg,subs='attributes',width="100%"]
 ....
-<%= JSON.dump csr.wavedrom_desc(arch_def, 64) %>
+<%= JSON.dump csr.wavedrom_desc(arch_def, 64, exclude_unimplemented: true) %>
 ....
 
 

backends/manual/tasks.rake

@@ -347,9 +347,10 @@ end
 Dir.glob($root / "arch" / "manual" / "**" / "contents.yaml") do |content_fn|
   file "#{File.dirname(content_fn)}/riscv-isa-manual/README.md" => ($root / "ext" / "riscv-isa-manual" / "README.md").to_s do |t|
     content_obj = YAML.load_file(content_fn)
+    git_dir = `git rev-parse --git-dir`.strip
     cmd = [
       "git",
-      "--git-dir=#{$root}/.git/modules/ext/riscv-isa-manual",
+      "--git-dir=#{git_dir}/modules/ext/riscv-isa-manual",
       "worktree add",
       File.dirname(t.name),
       content_obj["isa_manual_tree"],

bin/setup

@@ -19,6 +19,12 @@ else
   SINGULARITY_CACHE=
 fi
 
+if [ -f $ROOT/.git ]; then
+  # if this is a worktree, need to add the parent git repo in, too
+  GIT_PATH=`git rev-parse --git-common-dir | tr -d '\n' | xargs dirname`
+  HOME_OPT="${HOME_OPT} --bind ${GIT_PATH}:${GIT_PATH}"
+fi
+
 if [ ! -d $ROOT/.home ]; then
   mkdir $ROOT/.home
 fi

cfgs/generic_rv64/params.yaml

@@ -505,4 +505,6 @@ params:
   TINST_VALUE_ON_LOAD_PAGE_FAULT: "always zero"
   TINST_VALUE_ON_STORE_AMO_PAGE_FAULT: "always zero"
   MTVEC_MODES: [0, 1]
-
+  MSTATUS_FS_LEGAL_VALUES: [0,1,2,3]
+  MSTATUS_FS_WRITEABLE: true
+  MSTATUS_TVM_IMPLEMENTED: true