Change reset to active-low.

4 files changed, 16 insertions, 17 deletions

diff --git a/common/rtl/novena_regs.v b/common/rtl/novena_regs.v
index eb89092..4edf028 100644
--- a/common/rtl/novena_regs.v
+++ b/common/rtl/novena_regs.v
@@ -42,7 +42,7 @@ module board_regs
   (
    // Clock and reset.
    input wire           clk,
-   input wire           rst,
+   input wire           reset_n,
 
    // Control.
    input wire           cs,
@@ -96,9 +96,9 @@ module board_regs
    //----------------------------------------------------------------
    // storage registers for mapping memory to core interface
    //----------------------------------------------------------------
-   always @ (posedge clk or posedge rst)
+   always @ (posedge clk or negedge reset_n)
      begin
-        if (rst)
+        if (!reset_n)
           begin
              reg_dummy <= {32{1'b0}};
           end
diff --git a/eim/rtl/novena_eim.v b/eim/rtl/novena_eim.v
index 2de6cba..a8aee9b 100644
--- a/eim/rtl/novena_eim.v
+++ b/eim/rtl/novena_eim.v
@@ -75,7 +75,7 @@ module novena_top
    // and implement the reset logic.
    // ----------------------------------------------------------------
    wire                 sys_clk;
-   wire                 sys_rst;
+   wire                 sys_rst_n;
    wire                 eim_bclk_buf;
 
    novena_clkmgr #
@@ -91,7 +91,7 @@ module novena_top
       .reset_mcu_b      (reset_mcu_b_pin),
 
       .sys_clk          (sys_clk),
-      .sys_rst          (sys_rst)
+      .sys_rst_n        (sys_rst_n)
       );
 
 
@@ -128,7 +128,7 @@ module novena_top
       .eim_wait_n(eim_wait_n),
 
       .sys_clk(sys_clk),
-      .sys_rst(sys_rst),
+      .sys_rst_n(sys_rst_n),
 
       .sys_eim_addr(sys_eim_addr),
       .sys_eim_wr(sys_eim_wr),
@@ -159,7 +159,7 @@ module novena_top
    core_selector cores
      (
       .sys_clk(sys_clk),
-      .sys_rst(sys_rst),
+      .sys_rst_n(sys_rst_n),
 
       .sys_eim_addr(sys_eim_addr),
       .sys_eim_wr(sys_eim_wr),
diff --git a/fmc/rtl/novena_fmc_top.v b/fmc/rtl/novena_fmc_top.v
index 75c6f6d..37fdc49 100644
--- a/fmc/rtl/novena_fmc_top.v
+++ b/fmc/rtl/novena_fmc_top.v
@@ -71,7 +71,7 @@ module novena_fmc_top
    // and implement the reset logic.
    // ----------------------------------------------------------------
    wire               sys_clk;
-   wire               sys_rst;
+   wire               sys_rst_n;
 
    novena_clkmgr #
      (
@@ -86,7 +86,7 @@ module novena_fmc_top
       .reset_mcu_b      (reset_mcu_b_pin),
 
       .sys_clk          (sys_clk),
-      .sys_rst          (sys_rst)
+      .sys_rst_n        (sys_rst_n)
       );
 
 
@@ -154,7 +154,7 @@ module novena_fmc_top
    fmc_indicator led
      (
       .sys_clk(sys_clk),
-      .sys_rst(sys_rst),
+      .sys_rst_n(sys_rst_n),
       .fmc_active(sys_fmc_wren | sys_fmc_rden),
       .led_out(led_pin)
       );
@@ -220,7 +220,7 @@ module novena_fmc_top
    core_selector cores
      (
       .sys_clk(sys_clk),
-      .sys_rst(sys_rst),
+      .sys_rst_n(sys_rst_n),
 
       .sys_eim_addr(sys_fmc_addr[16:0]),	// XXX parameterize
       .sys_eim_wr(sys_fmc_wren),
diff --git a/i2c/rtl/novena_i2c.v b/i2c/rtl/novena_i2c.v
index c70f691..4ea6f82 100644
--- a/i2c/rtl/novena_i2c.v
+++ b/i2c/rtl/novena_i2c.v
@@ -67,7 +67,7 @@ module novena_top
    // and implement the reset logic.
    // ----------------------------------------------------------------
    wire                 sys_clk;
-   wire                 sys_rst;
+   wire                 sys_rst_n;
 
    novena_clkmgr #
      (
@@ -82,7 +82,7 @@ module novena_top
       .reset_mcu_b(reset_mcu_b_pin),
 
       .sys_clk(sys_clk),
-      .sys_rst(sys_rst)
+      .sys_rst_n(sys_rst_n)
       );
 
 
@@ -101,7 +101,6 @@ module novena_top
    wire 		sda_int;
    
    wire 		clk = sys_clk;
-   wire 		reset_n = ~sys_rst;
 
    // Coretest connections.
    wire 		coretest_reset_n;
@@ -132,7 +131,7 @@ module novena_top
    i2c_core i2c_core
      (
       .clk(clk),
-      .reset(sys_rst),
+      .reset(~sys_rst_n),       // active-high reset for this third-party module
 
       // External data interface
       .SCL(i2c_scl),
@@ -154,7 +153,7 @@ module novena_top
    coretest coretest
      (
       .clk(clk),
-      .reset_n(reset_n),
+      .reset_n(sys_rst_n),
       
       .rx_syn(i2c_rxd_syn),
       .rx_data(i2c_rxd_data),
@@ -189,7 +188,7 @@ module novena_top
    core_selector cores
      (
       .sys_clk(clk),
-      .sys_rst(sys_rst),
+      .sys_rst_n(sys_rst_n),
 
       .sys_eim_addr(sys_eim_addr),
       .sys_eim_wr(sys_eim_wr),