hsoc: add timer

rtl/soc/hydrogensoc/HydrogenSoC.v

@@ -108,7 +108,7 @@ module HydrogenSoC(
         `ifdef EN_EXCEPT
         ,
         .irq_i          (1'b0),
-        .timer_int_i    (1'b0)
+        .timer_int_i    (timer_int_o)
         `endif // EN_EXCEPT
     );
 
@@ -182,7 +182,7 @@ module HydrogenSoC(
 
 
     // ******************** Crossbar ********************
-    Crossbar5_wb #(
+    Crossbar6_wb #(
         .DATA_WIDTH     (32),
         .ADDR_WIDTH     (32),
         .DEVICE0_ADDR   (`BOOTROM_ADDR),
@@ -194,7 +194,9 @@ module HydrogenSoC(
         .DEVICE3_ADDR   (`GPIO_ADDR),
         .DEVICE3_MASK   (`size_to_mask32(`GPIO_SIZE)),
         .DEVICE4_ADDR   (`SPI_ADDR),
-        .DEVICE4_MASK   (`size_to_mask32(`SPI_SIZE))
+        .DEVICE4_MASK   (`size_to_mask32(`SPI_SIZE)),
+        .DEVICE5_ADDR   (`TIMER_ADDR),
+        .DEVICE5_MASK   (`size_to_mask32(`TIMER_SIZE))
     ) xbar (
         .wbs_adr_i      (arb_wb_adr_o),
         .wbs_dat_i      (arb_wb_dat_o),
@@ -256,7 +258,17 @@ module HydrogenSoC(
         .wbm4_cyc_o     (spi_wb_cyc_i),
         .wbm4_stb_o     (spi_wb_stb_i),
         .wbm4_ack_i     (spi_wb_ack_o),
-        .wbm4_err_i     (1'b0)
+        .wbm4_err_i     (1'b0),
+
+        .wbm5_adr_o     (timer_wb_adr_i),
+        .wbm5_dat_i     (timer_wb_dat_o),
+        .wbm5_dat_o     (timer_wb_dat_i),
+        .wbm5_we_o      (timer_wb_we_i),
+        .wbm5_sel_o     (timer_wb_sel_i),
+        .wbm5_cyc_o     (timer_wb_cyc_i),
+        .wbm5_stb_o     (timer_wb_stb_i),
+        .wbm5_ack_i     (timer_wb_ack_o),
+        .wbm5_err_i     (1'b0)
     );
 
 
@@ -410,6 +422,34 @@ module HydrogenSoC(
         .miso_i     (spi_miso_i),
         .mosi_o     (spi_mosi_o),
         .cs_o       (spi_cs_o)
+    );
+
+    // ******************* TIMER *******************
+    /* verilator lint_off UNUSEDSIGNAL */
+    wire  [31:0]    timer_wb_adr_i;
+    /* verilator lint_on UNUSEDSIGNAL */
+    wire  [31:0]    timer_wb_dat_o;
+    wire  [31:0]    timer_wb_dat_i;
+    wire 		    timer_wb_we_i;
+    wire  [3:0]     timer_wb_sel_i;
+    wire            timer_wb_cyc_i;
+    wire            timer_wb_stb_i;
+    wire 		    timer_wb_ack_o;
+    wire            timer_int_o;
+
+    Timer_wb timer (
+        .wb_clk_i   (wb_clk_i),
+        .wb_rst_i   (wb_rst_i),
+
+        .wb_adr_i   (timer_wb_adr_i[3:2]),
+        .wb_dat_o   (timer_wb_dat_o),
+        .wb_dat_i   (timer_wb_dat_i),
+        .wb_we_i    (timer_wb_we_i),
+        .wb_sel_i   (timer_wb_sel_i),
+        .wb_stb_i   (timer_wb_stb_i & timer_wb_cyc_i),
+        .wb_ack_o   (timer_wb_ack_o),
+
+        .int_o      (timer_int_o)
 );
 
 

rtl/soc/hydrogensoc/HydrogenSoC_Config.vh

@@ -87,5 +87,9 @@
 `define SPI_ADDR        32'h4000_3000
 `define SPI_SIZE        32              // 32 bytes (8 words)
 
+// TIMER
+`define TIMER_ADDR      32'h4000_4000
+`define TIMER_SIZE      16              // 32 bytes (4 words)
+
 
 `endif // __HYDROGENSOC_CONFIG_VH__

rtl/uncore/timer/README.md

@@ -0,0 +1,21 @@
+# Wishbone Timer
+Timer IP with Wishbone B-4 Interface.
+
+## Register MAP
+
+| **Offset** | **Name**   | **Description**
+|------------|------------|-----------------------------------
+| 0x00       | MTIME      | Machine mode time register [31:0]
+| 0x04       | MTIME_H    | Machine mode time register [63:32]
+| 0x08       | MTIMECMP   | Machine mode time compare register [31:0]
+| 0x0c       | MTIMECMP_H | Machine mode time compare register [63:32]
+
+> Timer interrupt (`mti`) is generated whenever `mtimecmp` >= `mtime`. The `mti` interrupt does not repeat, so the ISR needs to reset the timer compare register (`mtimecmp`) at each timeout.
+
+## Logic Utilization
+Yosys was used to analyze Logic utilization for Xilinx 7 series FPGAs
+
+| **Design**    | **LUTS** |
+|---------------|----------|
+| SPI_core      | 322      |
+| SPI_wb        | 530      |

rtl/uncore/timer/Timer_wb.v

@@ -0,0 +1,104 @@
+////////////////////////////////////////////////////////////////////   
+//  File        : GPIO.v
+//  Author      : Saurabh Singh ([email protected])
+//  Description : GPIO IP with Wishbone B-4 Interface.
+//
+// MIT License
+//
+// Copyright (c) 2021 Saurabh Singh
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+////////////////////////////////////////////////////////////////////
+
+`default_nettype none
+`include "Utils.vh"
+
+module Timer_wb(
+    // Wishbone Interface
+    input   wire            wb_clk_i,
+    input   wire            wb_rst_i,
+
+    input   wire    [3:2]   wb_adr_i,
+    output  reg     [31:0]  wb_dat_o,
+    input   wire    [31:0]  wb_dat_i,
+    input   wire            wb_we_i,
+    input   wire    [3:0]   wb_sel_i,
+    input   wire            wb_stb_i,
+    output  reg             wb_ack_o,
+
+    output  wire            int_o
+);
+
+// Set Ack_o
+always @(posedge wb_clk_i) begin
+  if (wb_rst_i)
+    wb_ack_o <= 1'b0;
+  else
+    wb_ack_o <= wb_stb_i & !wb_ack_o;
+end
+
+wire    [3:0]   we  = {4{wb_we_i & wb_stb_i}} & wb_sel_i;
+
+
+reg     [63:0]  mtime;
+reg     [63:0]  mtimecmp;
+
+assign int_o = mtime >= mtimecmp;
+
+// Writes
+always @(posedge wb_clk_i) begin
+    if(wb_rst_i) begin
+        mtime       <= 'd0;
+        mtimecmp    <= 'd0;
+    end
+    else begin
+        case(wb_adr_i)
+            2'b10: begin  // mtimecmp
+                    if (we[0])  mtimecmp[7:0]       <= wb_dat_i[7:0];
+                    if (we[1])  mtimecmp[15:8]      <= wb_dat_i[15:8];
+                    if (we[2])  mtimecmp[23:16]     <= wb_dat_i[23:16];
+                    if (we[3])  mtimecmp[31:24]     <= wb_dat_i[31:24];
+                end
+            2'b11: begin   // mtimecmp_h
+                    if (we[0])  mtimecmp[39:32]     <= wb_dat_i[7:0];
+                    if (we[1])  mtimecmp[47:40]     <= wb_dat_i[15:8];
+                    if (we[2])  mtimecmp[55:48]     <= wb_dat_i[23:16];
+                    if (we[3])  mtimecmp[63:56]     <= wb_dat_i[31:24];
+                end
+            default: begin   // INC  (NOT IMPLEMENTED)
+            end
+        endcase
+        mtime <= mtime + 'd1;
+    end
+end
+
+
+// READS
+always @(*) /* COMBINATORIAL */ begin
+    case(wb_adr_i)
+        2'b00:  /* mtime */         wb_dat_o = mtime[31:0];
+        2'b01:  /* mtime_h */       wb_dat_o = mtime[63:32];
+        2'b10:  /* mtimecmp */      wb_dat_o = mtimecmp[31:0];
+        2'b11:  /* mtimecmp_h */    wb_dat_o = mtimecmp[63:32];
+        default:
+            wb_dat_o = 'dx;
+    endcase
+end
+
+endmodule