Merge pull request #899 from openhwgroup/dev

Automatic PR dev->master
openhwgroup · Nov 7, 2023 · e70418e · e70418e
2 parents c08638e + 40f6edf
commit e70418e
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diff --git a/docs/source/control_status_registers.rst b/docs/source/control_status_registers.rst
@@ -445,7 +445,7 @@ Detailed:
   +-------------+-----------+-------------------------------------------------------------------------------------------------------------------------+
   | 30:15       | RO        | 0, Unimplemented.                                                                                                       |
   +-------------+-----------+-------------------------------------------------------------------------------------------------------------------------+
-  | 14:13       | RW        | **FS:** Floating point State                                                                                            |
+  | 14:13       | RW        | **FS:** Floating point State (See note below)                                                                           |
   |             |           |                                                                                                                         |
   |             |           | 00 = Off                                                                                                                |
   |             |           |                                                                                                                         |
@@ -457,13 +457,13 @@ Detailed:
   |             |           |                                                                                                                         |
   |             |           | 0 if ``FPU`` = 0 or (``FPU`` = 1 and ``ZFINX`` = 1).                                                                    |
   +-------------+-----------+-------------------------------------------------------------------------------------------------------------------------+
-  | 12:11       | RO        | **MPP:** Machine Previous Priviledge mode                                                                               |
+  | 12:11       | RW        | **MPP:** Machine Previous Priviledge mode                                                                               |
   |             |           |                                                                                                                         |
-  |             |           | 11 when the user mode is not enabled.                                                                                   |
+  |             |           | Hardwired to 11 when the User mode is not enabled.                                                                      |
   +-------------+-----------+-------------------------------------------------------------------------------------------------------------------------+
   | 10:8        | RO        | 0, Unimplemented.                                                                                                       |
   +-------------+-----------+-------------------------------------------------------------------------------------------------------------------------+
-  | 7           | RO        | **MPIE:** Machine Previous Interrupt Enable                                                                             |
+  | 7           | RW        | **MPIE:** Machine Previous Interrupt Enable                                                                             |
   |             |           |                                                                                                                         |
   |             |           | When an exception is encountered, MPIE will be set to MIE.                                                              |
   |             |           | When the mret instruction is executed, the value of MPIE will be stored to MIE.                                         |
@@ -478,6 +478,10 @@ Detailed:
   | 2:0         | RO        | 0, Unimplemented.                                                                                                       |
   +-------------+-----------+-------------------------------------------------------------------------------------------------------------------------+
 
+.. note::
+
+   As allowed by RISC-V ISA and to simplify MSTATUS.FS update in the design, the state is updated to Dirty when executing any F instructions except for all FSW ones.
+
 .. only:: USER
 
   User Status (``ustatus``)
@@ -652,8 +656,10 @@ Detailed:
   | 4:0         |   RW      | **Exception Code**   (See note below)                                            |
   +-------------+-----------+----------------------------------------------------------------------------------+
 
-**NOTE**: software accesses to `mcause[4:0]` must be sensitive to the WLRL field specification of this CSR. For example,
-when `mcause[31]` is set, writing 0x1 to `mcause[1]` (Supervisor software interrupt) will result in UNDEFINED behavior.
+.. note::
+
+   Software accesses to `mcause[4:0]` must be sensitive to the WLRL field specification of this CSR. For example,
+   when `mcause[31]` is set, writing 0x1 to `mcause[1]` (Supervisor software interrupt) will result in UNDEFINED behavior.
 
 
 Machine Trap Value (``mtval``)
@@ -1603,8 +1609,10 @@ Detailed:
   | 4:0         |   RW      | **Exception Code**   (See note below)                                              |
   +-------------+-----------+------------------------------------------------------------------------------------+
 
-  **NOTE**: software accesses to `ucause[4:0]` must be sensitive to the WLRL field specification of this CSR.  For example,
-  when `ucause[31]` is set, writing 0x1 to `ucause[1]` (Supervisor software interrupt) will result in UNDEFINED behavior.
+  .. note::
+
+   Software accesses to `ucause[4:0]` must be sensitive to the WLRL field specification of this CSR. For example,
+   when `ucause[31]` is set, writing 0x1 to `ucause[1]` (Supervisor software interrupt) will result in UNDEFINED behavior.
 
 
 .. only:: PMP

diff --git a/docs/source/fpu.rst b/docs/source/fpu.rst
@@ -25,7 +25,7 @@ precision can be enabled by setting the parameter **FPU** of the ``cv32e40p_top`
 to 1. This will extend the CV32E40P decoder accordingly and will instantiate the FPU.
 The FPU repository used by the CV32E40P is available at `https://github.com/openhwgroup/cvfpu <https://github.com/openhwgroup/cvfpu/tree/3116391bf66660f806b45e212b9949c528b4e270>`_ and
 its documentation can be found `here <https://github.com/openhwgroup/cvfpu/blob/3116391bf66660f806b45e212b9949c528b4e270/docs/README.md>`_.
-CVFPU v1.0.0 release has been copied in CV32E40P repository inside rtl/vendor (used for verification and implementation) so all core and FPU RTL files should be taken from CV32E40P repository.
+CVFPU v0.8.1 release has been copied in CV32E40P repository inside rtl/vendor (used for verification and implementation) so all core and FPU RTL files should be taken from CV32E40P repository.
 
 cv32e40p_fpu_manifest file is listing all necessary files for both the Core and CVFPU.
 

diff --git a/rtl/cv32e40p_controller.sv b/rtl/cv32e40p_controller.sv
@@ -491,6 +491,7 @@ module cv32e40p_controller import cv32e40p_pkg::*;
             if ( (debug_req_pending || trigger_match_i) & ~debug_mode_q )
               begin
                 //Serving the debug
+                is_decoding_o     = COREV_PULP ? 1'b0 : 1'b1;
                 halt_if_o         = 1'b1;
                 halt_id_o         = 1'b1;
                 ctrl_fsm_ns       = DBG_FLUSH;
@@ -712,6 +713,7 @@ module cv32e40p_controller import cv32e40p_pkg::*;
             if ( (debug_req_pending || trigger_match_i) & ~debug_mode_q )
               begin
                 //Serving the debug
+                is_decoding_o     = COREV_PULP ? 1'b0 : 1'b1;
                 halt_if_o         = 1'b1;
                 halt_id_o         = 1'b1;
                 ctrl_fsm_ns       = DBG_FLUSH;

diff --git a/rtl/cv32e40p_core.sv b/rtl/cv32e40p_core.sv
@@ -158,6 +158,7 @@ module cv32e40p_core
   logic [31:0] jump_target_id, jump_target_ex;
   logic               branch_in_ex;
   logic               branch_decision;
+  logic        [ 1:0] ctrl_transfer_insn_in_dec;
 
   logic               ctrl_busy;
   logic               if_busy;
@@ -201,6 +202,7 @@ module cv32e40p_core
   logic        [            C_RM-1:0]       frm_csr;
   logic        [         C_FFLAG-1:0]       fflags_csr;
   logic                                     fflags_we;
+  logic                                     fregs_we;
 
   // APU
   logic                                     apu_en_ex;
@@ -540,9 +542,10 @@ module cv32e40p_core
       .instr_req_o  (instr_req_int),
 
       // Jumps and branches
-      .branch_in_ex_o   (branch_in_ex),
-      .branch_decision_i(branch_decision),
-      .jump_target_o    (jump_target_id),
+      .branch_in_ex_o             (branch_in_ex),
+      .branch_decision_i          (branch_decision),
+      .jump_target_o              (jump_target_id),
+      .ctrl_transfer_insn_in_dec_o(ctrl_transfer_insn_in_dec),
 
       // IF and ID control signals
       .clear_instr_valid_o(clear_instr_valid),
@@ -785,6 +788,8 @@ module cv32e40p_core
       .data_misaligned_ex_i(data_misaligned_ex),  // from ID/EX pipeline
       .data_misaligned_i   (data_misaligned),
 
+      .ctrl_transfer_insn_in_dec_i(ctrl_transfer_insn_in_dec),
+
       // FPU
       .fpu_fflags_we_o(fflags_we),
       .fpu_fflags_o   (fflags_csr),
@@ -969,6 +974,7 @@ module cv32e40p_core
       .frm_o      (frm_csr),
       .fflags_i   (fflags_csr),
       .fflags_we_i(fflags_we),
+      .fregs_we_i (fregs_we),
 
       // Interrupt related control signals
       .mie_bypass_o  (mie_bypass),
@@ -1037,13 +1043,16 @@ module cv32e40p_core
   );
 
   //  CSR access
-  assign csr_addr     = csr_addr_int;
-  assign csr_wdata    = alu_operand_a_ex;
-  assign csr_op       = csr_op_ex;
+  assign csr_addr = csr_addr_int;
+  assign csr_wdata = alu_operand_a_ex;
+  assign csr_op = csr_op_ex;
 
   assign csr_addr_int = csr_num_e'(csr_access_ex ? alu_operand_b_ex[11:0] : '0);
 
-
+  //  Floating-Point registers write
+  assign fregs_we     = (FPU & !ZFINX) ? ((regfile_alu_we_fw && regfile_alu_waddr_fw[5]) ||
+                                          (regfile_we_wb     && regfile_waddr_fw_wb_o[5]))
+                                       : 1'b0;
 
   ///////////////////////////
   //   ____  __  __ ____   //

diff --git a/rtl/cv32e40p_cs_registers.sv b/rtl/cv32e40p_cs_registers.sv
@@ -68,6 +68,7 @@ module cv32e40p_cs_registers
     output logic [        2:0] frm_o,
     input  logic [C_FFLAG-1:0] fflags_i,
     input  logic               fflags_we_i,
+    input  logic               fregs_we_i,
 
     // Interrupts
     output logic [31:0] mie_bypass_o,
@@ -212,6 +213,7 @@ module cv32e40p_cs_registers
 
   logic [31:0] exception_pc;
   Status_t mstatus_q, mstatus_n;
+  logic mstatus_we_int;
   FS_t mstatus_fs_q, mstatus_fs_n;
   logic [5:0] mcause_q, mcause_n;
   logic [5:0] ucause_q, ucause_n;
@@ -897,6 +899,7 @@ module cv32e40p_cs_registers
       dscratch0_n = dscratch0_q;
       dscratch1_n = dscratch1_q;
 
+      mstatus_we_int = 1'b0;
       mstatus_n = mstatus_q;
       mcause_n = mcause_q;
       ucause_n = '0;  // Not used if PULP_SECURE == 0
@@ -957,7 +960,8 @@ module cv32e40p_cs_registers
               mprv: csr_wdata_int[MSTATUS_MPRV_BIT]
           };
           if (FPU == 1 && ZFINX == 0) begin
-            mstatus_fs_n = FS_t'(csr_wdata_int[MSTATUS_FS_BIT_HIGH:MSTATUS_FS_BIT_LOW]);
+            mstatus_we_int = 1'b1;
+            mstatus_fs_n   = FS_t'(csr_wdata_int[MSTATUS_FS_BIT_HIGH:MSTATUS_FS_BIT_LOW]);
           end
         end
         // mie: machine interrupt enable
@@ -1027,7 +1031,7 @@ module cv32e40p_cs_registers
 
         if (ZFINX == 0) begin
           // FPU Register File/Flags implicit update or modified by CSR instructions
-          if (fflags_we_i || fcsr_update) begin
+          if ((fregs_we_i && !(mstatus_we_int && mstatus_fs_n != FS_DIRTY)) || fflags_we_i || fcsr_update) begin
             mstatus_fs_n = FS_DIRTY;
           end
         end

diff --git a/rtl/cv32e40p_ex_stage.sv b/rtl/cv32e40p_ex_stage.sv
@@ -81,6 +81,8 @@ module cv32e40p_ex_stage
     input logic data_misaligned_ex_i,
     input logic data_misaligned_i,
 
+    input logic [1:0] ctrl_transfer_insn_in_dec_i,
+
     // FPU signals
     output logic fpu_fflags_we_o,
     output logic [APU_NUSFLAGS_CPU-1:0] fpu_fflags_o,
@@ -371,19 +373,33 @@ module cv32e40p_ex_stage
           apu_result_q <= 'b0;
           apu_flags_q  <= 'b0;
         end else begin
-          if (apu_rvalid_i && apu_multicycle && (data_misaligned_i || data_misaligned_ex_i || (data_req_i && regfile_alu_we_i) || (mulh_active && (mult_operator_i == MUL_H)))) begin
+          if (apu_rvalid_i && apu_multicycle &&
+              (data_misaligned_i || data_misaligned_ex_i ||
+               ((data_req_i || data_rvalid_i) && regfile_alu_we_i) ||
+               (mulh_active && (mult_operator_i == MUL_H)) ||
+               ((ctrl_transfer_insn_in_dec_i == BRANCH_JALR) &&
+                regfile_alu_we_i && ~apu_read_dep_for_jalr_o))) begin
             apu_rvalid_q <= 1'b1;
             apu_result_q <= apu_result_i;
             apu_flags_q  <= apu_flags_i;
-          end else if (apu_rvalid_q && !(data_misaligned_i || data_misaligned_ex_i || ((data_req_i || data_rvalid_i) && regfile_alu_we_i) || (mulh_active && (mult_operator_i == MUL_H)))) begin
+          end else if (apu_rvalid_q && !(data_misaligned_i || data_misaligned_ex_i ||
+                                         ((data_req_i || data_rvalid_i) && regfile_alu_we_i) ||
+                                         (mulh_active && (mult_operator_i == MUL_H)) ||
+                                         ((ctrl_transfer_insn_in_dec_i == BRANCH_JALR) &&
+                                          regfile_alu_we_i && ~apu_read_dep_for_jalr_o))) begin
             apu_rvalid_q <= 1'b0;
           end
         end
       end
 
       assign apu_req_o = apu_req;
       assign apu_gnt = apu_gnt_i;
-      assign apu_valid = (apu_multicycle && (data_misaligned_i || data_misaligned_ex_i || ((data_req_i || data_rvalid_i) && regfile_alu_we_i) || (mulh_active && (mult_operator_i == MUL_H)))) ? 1'b0 : (apu_rvalid_i || apu_rvalid_q);
+      assign apu_valid = (apu_multicycle && (data_misaligned_i || data_misaligned_ex_i ||
+                                             ((data_req_i || data_rvalid_i) && regfile_alu_we_i) ||
+                                             (mulh_active && (mult_operator_i == MUL_H)) ||
+                                             ((ctrl_transfer_insn_in_dec_i == BRANCH_JALR) &&
+                                              regfile_alu_we_i && ~apu_read_dep_for_jalr_o)))
+                         ? 1'b0 : (apu_rvalid_i || apu_rvalid_q);
       assign apu_operands_o = apu_operands_i;
       assign apu_op_o = apu_op_i;
       assign apu_result = apu_rvalid_q ? apu_result_q : apu_result_i;

diff --git a/rtl/cv32e40p_fp_wrapper.sv b/rtl/cv32e40p_fp_wrapper.sv
@@ -111,7 +111,7 @@ module cv32e40p_fp_wrapper
       .int_fmt_i     (fpnew_pkg::int_format_e'(fpu_int_fmt)),
       .vectorial_op_i(fpu_vec_op),
       .tag_i         (1'b0),
-      .simd_mask_i   ('b0),
+      .simd_mask_i   (1'b0),
       .in_valid_i    (apu_req_i),
       .in_ready_o    (apu_gnt_o),
       .flush_i       (1'b0),

diff --git a/rtl/cv32e40p_id_stage.sv b/rtl/cv32e40p_id_stage.sv
@@ -70,6 +70,7 @@ module cv32e40p_id_stage
     output logic        branch_in_ex_o,
     input  logic        branch_decision_i,
     output logic [31:0] jump_target_o,
+    output logic [ 1:0] ctrl_transfer_insn_in_dec_o,
 
     // IF and ID stage signals
     output logic       clear_instr_valid_o,
@@ -1087,7 +1088,7 @@ module cv32e40p_id_stage
       .debug_wfi_no_sleep_i(debug_wfi_no_sleep),
 
       // jump/branches
-      .ctrl_transfer_insn_in_dec_o   (ctrl_transfer_insn_in_dec),
+      .ctrl_transfer_insn_in_dec_o   (ctrl_transfer_insn_in_dec_o),
       .ctrl_transfer_insn_in_id_o    (ctrl_transfer_insn_in_id),
       .ctrl_transfer_target_mux_sel_o(ctrl_transfer_target_mux_sel),
 
@@ -1187,7 +1188,7 @@ module cv32e40p_id_stage
       // jump/branch control
       .branch_taken_ex_i          (branch_taken_ex),
       .ctrl_transfer_insn_in_id_i (ctrl_transfer_insn_in_id),
-      .ctrl_transfer_insn_in_dec_i(ctrl_transfer_insn_in_dec),
+      .ctrl_transfer_insn_in_dec_i(ctrl_transfer_insn_in_dec_o),
 
       // Interrupt signals
       .irq_wu_ctrl_i     (irq_wu_ctrl),