i3c_controller: Naming convention, corner case fix (#1314)

Rename "idle bus" to "bus available" per specification:
* Tune it to require < 1us.

Rename "IBI auto" to "IBI listen":
* Clarify that the controller is listening for IBI's:
* Explain that this field should be set.
* Fix for known IBI's DA with IBI disabled.

Signed-off-by: Jorge Marques <jorge.marques@analog.com>

docs/library/i3c_controller/i3c_controller_core.rst

@@ -22,6 +22,10 @@ Files
      - Verilog source for the peripheral.
    * - :git-hdl:`master:library/i3c_controller/i3c_controller_core/i3c_controller_core.tcl`
      - TCL script to generate the Vivado IP-integrator project for the peripheral.
+   * - :git-hdl:`master:library/i3c_controller/i3c_controller_core/i3c_controller_core_ip.tcl`
+     - TCL script to generate the Vivado IP-integrator project for the peripheral.
+   * - :git-hdl:`master:library/i3c_controller/i3c_controller_core/i3c_controller_core_hw.tcl`
+     - TCL script to generate the Quartus IP-integrator project for the peripheral.
 
 
 Configuration Parameters
@@ -38,7 +42,3 @@ Signal and Interface Pins
 --------------------------------------------------------------------------------
 
 .. hdl-interfaces::
-
-Theory of Operation
---------------------------------------------------------------------------------
-

docs/library/i3c_controller/i3c_controller_host_interface.rst

@@ -25,8 +25,10 @@ Files
      - Description
    * - :git-hdl:`master:library/i3c_controller/i3c_controller_host_interface/i3c_controller_host_interface.v`
      - Verilog source for the peripheral.
-   * - :git-hdl:`master:library/i3c_controller/i3c_controller_host_interface/i3c_controller_host_interface.tcl`
+   * - :git-hdl:`master:library/i3c_controller/i3c_controller_host_interface/i3c_controller_host_interface_ip.tcl`
      - TCL script to generate the Vivado IP-integrator project for the peripheral.
+   * - :git-hdl:`master:library/i3c_controller/i3c_controller_host_interface/i3c_controller_host_interface_hw.tcl`
+     - TCL script to generate the Quartus IP-integrator project for the peripheral.
 
 Configuration Parameters
 --------------------------------------------------------------------------------
@@ -65,6 +67,8 @@ Signal and Interface Pins
      - Interface give the :ref:`i3c_controller core` access to some register map
        addresses.
 
+.. _i3c_controller regmap:
+
 Register Map
 --------------------------------------------------------------------------------
 

docs/library/i3c_controller/interface.rst

@@ -66,7 +66,7 @@ the following subsections.
 
 .. note::
 
-  CCC always broadcast header after an idle bus, therefore "Bcast. header"
+  CCC always broadcast header after a bus available, therefore "Bcast. header"
   is ignored for CCC\s.
 
 .. _i3c_controller ccc:
@@ -231,8 +231,11 @@ On software, check bit:
 In-Band Interrupts
 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 
-IBI\s are accepted autonomously during bus idle if the feature is enabled.
-The accepted IBI\s fill the IBI FIFO and generate an interrupt to the
+IBI's are resolved autonomously during bus available per specification,
+if they are accepted or rejected depends if the feature itself is enabled;
+see I3C Controller's :ref:`i3c_controller regmap` register ``IBI_CONFIG`` for
+more info.
+The accepted IBI's fill the IBI FIFO and generate an interrupt to the
 PS.
 
 The structure of the received IBI is:

docs/regmap/adi_regmap_i3c_controller.txt

@@ -466,7 +466,7 @@ OPS_STATUS_NOP
 RO
 This bit is set to 1 when the bus is not executing any procedure.
 It is not idle bus condition since it set right after the Stop.
-ENDIELD
+ENDFIELD
 
 FIELD
 [6:5] 0x0
@@ -505,12 +505,12 @@ ENDREG
 
 FIELD
 [1] 0x0
-IBI_CONFIG_AUTO
+IBI_CONFIG_LISTEN
 WO
-Set this bit to listen for IBI requests (when a peripheral pulls SDA Low during quiet times).
+Set this bit to listen for IBI requests (when a peripheral pulls SDA Low during bus available).
 After the IBI request is resolved, the controller returns to idle, since it is was not doing
 a cmd transfer.
-IBI_CONFIG_ENABLE must be set 1.
+This should be set to 1 during normal operation, even if IBI_CONFIG_ENABLE is disabled.
 ENDFIELD
 
 FIELD
@@ -521,8 +521,10 @@ Set this bit to accept (ACK) IBI requests.
 If disabled, the controller will NACK IBI requests.
 If enabled, the controller will ACK the IBI request and receive the MDB.
 In both cases, the controller will proceed with the cmd transfer after resolving the IBI
-request.
-Accepted IBIs fill the IBI_FIFO and generate an interruption in the PS.
+request, if any.
+Accepted IBIs fill the IBI_FIFO and generate an interrupt to the PS.
+IBI_CONFIG_LISTEN set to 1 and IBI_CONFIG_ENABLE set to 0 ensures that incoming IBIs are
+rejected as they come.
 ENDFIELD
 
 ############################################################################################
@@ -552,9 +554,9 @@ ENDFIELD
 
 FIELD
 [3] 0x0
-DEV_CHAR_HAS_IBI_MDB
+DEV_CHAR_HAS_IBI_PAYLOAD
 RW
-Indicates if the device sends an MDB during the IBI.
+Indicates if the device sends at least MDB during the IBI.
 0 does not, 1 does.
 ENDFIELD
 

library/i3c_controller/i3c_controller_core/i3c_controller_bit_mod.v

@@ -62,7 +62,7 @@ module i3c_controller_bit_mod #(
   // Mux to alternative logic to support I²C devices.
   input  i2c_mode,
   // Indicates that the bus is not transferring,
-  // is *not* bus idle condition because does not wait 200us after P.
+  // is *not* bus available condition because does not wait 1s after P.
   output nop,
   // 0:  1.56MHz
   // 1:  3.12MHz

library/i3c_controller/i3c_controller_core/i3c_controller_core.v

@@ -110,7 +110,8 @@ module i3c_controller_core #(
   wire i2c_mode;
 
   i3c_controller_framing #(
-    .MAX_DEVS(MAX_DEVS)
+    .MAX_DEVS(MAX_DEVS),
+    .CLK_MOD(CLK_MOD)
   ) i_i3c_controller_framing (
     .reset_n(reset_n),
     .clk(clk),

library/i3c_controller/i3c_controller_core/i3c_controller_framing.v

@@ -64,7 +64,8 @@
 `include "i3c_controller_word.vh"
 
 module i3c_controller_framing #(
-  parameter MAX_DEVS = 16
+  parameter MAX_DEVS = 16,
+  parameter CLK_MOD = 0
 ) (
   input         clk,
   input         reset_n,
@@ -114,7 +115,9 @@ module i3c_controller_framing #(
   input  [3:0]  rmap_dev_char_data
 );
 
-  localparam IDLE_BUS_WIDTH = 7;
+  // Defines the bus available condition width (> 1us for target)
+  // Setting around 0.64us for the controller.
+  localparam BUS_AVAIL = CLK_MOD ? 4 : 5;
 
   localparam [2:0] SM_SETUP       = 0;
   localparam [2:0] SM_VALIDATE    = 1;
@@ -126,7 +129,7 @@ module i3c_controller_framing #(
   localparam [6:0] CCC_ENTDAA = 'h07;
 
   reg [`CMDW_HEADER_WIDTH:0] st;
-  reg [IDLE_BUS_WIDTH:0] idle_bus_reg;
+  reg [BUS_AVAIL:0] bus_avail_reg;
   reg        cmdp_ccc_reg;
   reg        cmdp_ccc_bcast_reg;
   reg [6:0]  cmdp_ccc_id_reg;
@@ -147,9 +150,9 @@ module i3c_controller_framing #(
   reg        error_nack_resp ;
   reg [2:0]  sm;
 
-  wire        idle_bus;
+  wire        bus_avail;
   wire        ibi_enable;
-  wire        ibi_auto;
+  wire        ibi_listen;
   wire        cmdp_rnw;
   wire [6:0]  cmdp_da;
   wire [11:0] cmdp_buffer_len;
@@ -202,7 +205,7 @@ module i3c_controller_framing #(
             // Direct is CCC_BCAST 1'b1
             sm <= cmdp_ccc & ~cmdp_ccc_bcast ? SM_TRANSFER : SM_VALIDATE;
             ctrl_validate <= 1'b0;
-          end else if (ibi_auto & ibi_enable & rx === 1'b0 & idle_bus) begin
+          end else if (ibi_listen & rx === 1'b0 & bus_avail) begin
             st <= `CMDW_BCAST_7E_W0;
             sm <= SM_TRANSFER;
             ibi_requested_auto <= 1'b1;
@@ -362,7 +365,7 @@ module i3c_controller_framing #(
             // At the word module, was ACKed if IBI is enabled and DA is known, if not, NACKed.
             if (ibi_requested) begin
               // Receive MSB if IBI is enabled, dev is known and BCR[2] is 1'b1.
-              if (dev_is_attached & ibi_enable & ibi_bcr_2) begin
+              if (ibi_enable & dev_is_attached & ibi_bcr_2) begin
                 st <= `CMDW_IBI_MDB;
               end else begin
                 st <= cmdp_valid_reg ? `CMDW_START : `CMDW_STOP_OD;
@@ -386,16 +389,15 @@ module i3c_controller_framing #(
     error_nack_bcast <= cmdw_nack_bcast;
   end
 
-  // Idle bus condition
-
+  // Bus available condition
   always @(posedge clk) begin
     if (!reset_n || !nop) begin
-      idle_bus_reg <= 0;
-    end else if (!idle_bus) begin
-      idle_bus_reg <= idle_bus_reg + 1;
+      bus_avail_reg <= 0;
+    end else if (!bus_avail) begin
+      bus_avail_reg <= bus_avail_reg + 1;
     end
   end
-  assign idle_bus = &idle_bus_reg;
+  assign bus_avail = &bus_avail_reg;
 
   // Device characteristics look-up.
 
@@ -412,7 +414,7 @@ module i3c_controller_framing #(
   assign cmdw_valid = sm == SM_TRANSFER;
 
   assign ibi_enable = rmap_ibi_config[0];
-  assign ibi_auto   = rmap_ibi_config[1];
+  assign ibi_listen = rmap_ibi_config[1];
 
   assign cmdp_rnw          = cmdp[0];
   assign cmdp_da           = cmdp[7:1];

library/i3c_controller/i3c_controller_core/i3c_controller_word.v

@@ -376,7 +376,7 @@ module i3c_controller_word (
                 ibi_requested <= i < 6 & rx === 1'b0 ? 1'b1 : ibi_requested;
                 if (i[2:0] == 7) begin
                   arbitration_valid <= 1'b1;
-                  if (ibi_dev_is_attached & ibi_requested & ~ibi_bcr_2) begin
+                  if (ibi_enable & ibi_requested & ibi_dev_is_attached & ~ibi_bcr_2) begin
                     ibi_tick <= 1'b1;
                   end
                 end