New testcase for the GPIO feature straps

Removed the assumption StrapSampleOnce_A, that does not work for cases that sample_trigger never fell or if we have more than one reset operation happening during the simulation. Signed-off-by: Marcelo Carvalho Faleiro de Almeida <[email protected]>
lowRISC · Jan 20, 2025 · 49e465c · 49e465c
1 parent 29d7b87
commit 49e465c
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diff --git a/hw/ip/gpio/data/gpio.hjson b/hw/ip/gpio/data/gpio.hjson
@@ -111,6 +111,7 @@
       package: "",
       desc:    '''
                This signal is pulsed high by the power manager after reset in order to sample the HW straps.
+               It can only be pulsed high one-time after reset. The following pulses will not be taken into consideration.
                ''',
       default: "1'b0"
     },
@@ -390,7 +391,14 @@
       ],
     },
     { name: "HW_STRAPS_DATA_IN",
-      desc: "GPIO Input data sampled as straps during cold boot read value",
+      desc: '''
+        GPIO input data that was sampled as straps as the block came out of reset.
+
+        This register depends on the GpioAsHwStrapsEn parameter.
+        - If the parameter is false then the register reads as zero.
+        - If the parameter is true then GPIO input data is sampled on the first cycle after reset
+          where the strap_en_i input is high. That sampled data is stored in this register.
+      ''',
       swaccess: "ro",
       hwaccess: "hrw",
       tags: [// Value in the register is determined by GPIO pin values that are sampled

diff --git a/hw/ip/gpio/data/gpio_testplan.hjson b/hw/ip/gpio/data/gpio_testplan.hjson
@@ -145,5 +145,20 @@
       stage: V2
       tests: ["gpio_stress_all"]
     }
+    {
+      name: straps_data
+      desc: '''Verify the straps data/valid ouput expected values based on the strap_en and gpio_i inputs:
+      - Drives gpio_i input with random values.
+      - Set the strap_en high for at least one clock cycle.
+      - Read the registers hw_straps_data_in and hw_straps_data_in_valid.
+      - The data read and sampled_straps_o will be checked in the scoreboard.
+      - Drive the gpio_o to make sure that has no impact on straps registers.
+      - Read to make sure that if does not affect the straps registers after drive the gpio_o.
+      - Apply reset and make sure the strap registers are clean.
+      - Read straps registers after reset.
+      - Iterate again the same flow, with new random values.'''
+      stage: V3
+      tests: ["gpio_rand_straps"]
+    }
   ]
 }
diff --git a/hw/ip/gpio/doc/interfaces.md b/hw/ip/gpio/doc/interfaces.md
@@ -15,11 +15,11 @@ Referring to the [Comportable guideline for peripheral device functionality](htt
 
 ## [Inter-Module Signals](https://opentitan.org/book/doc/contributing/hw/comportability/index.html#inter-signal-handling)
 
-| Port Name      | Package::Struct       | Type    | Act   |   Width | Description                                                                                   |
-|:---------------|:----------------------|:--------|:------|--------:|:----------------------------------------------------------------------------------------------|
-| strap_en       | logic                 | uni     | rcv   |       1 | This signal is pulsed high by the power manager after reset in order to sample the HW straps. |
-| sampled_straps | gpio_pkg::gpio_straps | uni     | req   |       1 | This vector contains the sampled strap values.                                                |
-| tl             | tlul_pkg::tl          | req_rsp | rsp   |       1 |                                                                                               |
+| Port Name      | Package::Struct       | Type    | Act   |   Width | Description                                                                                                                                                                                               |
+|:---------------|:----------------------|:--------|:------|--------:|:----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
+| strap_en       | logic                 | uni     | rcv   |       1 | This signal is pulsed high by the power manager after reset in order to sample the HW straps. It can only be pulsed high one-time after reset. The following pulses will not be taken into consideration. |
+| sampled_straps | gpio_pkg::gpio_straps | uni     | req   |       1 | This vector contains the sampled strap values.                                                                                                                                                            |
+| tl             | tlul_pkg::tl          | req_rsp | rsp   |       1 |                                                                                                                                                                                                           |
 
 ## Interrupts
 

diff --git a/hw/ip/gpio/doc/registers.md b/hw/ip/gpio/doc/registers.md
@@ -3,26 +3,26 @@
 <!-- BEGIN CMDGEN util/regtool.py -d ./hw/ip/gpio/data/gpio.hjson -->
 ## Summary
 
-| Name                                                       | Offset   |   Length | Description                                                   |
-|:-----------------------------------------------------------|:---------|---------:|:--------------------------------------------------------------|
-| gpio.[`INTR_STATE`](#intr_state)                           | 0x0      |        4 | Interrupt State Register                                      |
-| gpio.[`INTR_ENABLE`](#intr_enable)                         | 0x4      |        4 | Interrupt Enable Register                                     |
-| gpio.[`INTR_TEST`](#intr_test)                             | 0x8      |        4 | Interrupt Test Register                                       |
-| gpio.[`ALERT_TEST`](#alert_test)                           | 0xc      |        4 | Alert Test Register                                           |
-| gpio.[`DATA_IN`](#data_in)                                 | 0x10     |        4 | GPIO Input data read value                                    |
-| gpio.[`DIRECT_OUT`](#direct_out)                           | 0x14     |        4 | GPIO direct output data write value                           |
-| gpio.[`MASKED_OUT_LOWER`](#masked_out_lower)               | 0x18     |        4 | GPIO write data lower with mask.                              |
-| gpio.[`MASKED_OUT_UPPER`](#masked_out_upper)               | 0x1c     |        4 | GPIO write data upper with mask.                              |
-| gpio.[`DIRECT_OE`](#direct_oe)                             | 0x20     |        4 | GPIO Output Enable.                                           |
-| gpio.[`MASKED_OE_LOWER`](#masked_oe_lower)                 | 0x24     |        4 | GPIO write Output Enable lower with mask.                     |
-| gpio.[`MASKED_OE_UPPER`](#masked_oe_upper)                 | 0x28     |        4 | GPIO write Output Enable upper with mask.                     |
-| gpio.[`INTR_CTRL_EN_RISING`](#intr_ctrl_en_rising)         | 0x2c     |        4 | GPIO interrupt enable for GPIO, rising edge.                  |
-| gpio.[`INTR_CTRL_EN_FALLING`](#intr_ctrl_en_falling)       | 0x30     |        4 | GPIO interrupt enable for GPIO, falling edge.                 |
-| gpio.[`INTR_CTRL_EN_LVLHIGH`](#intr_ctrl_en_lvlhigh)       | 0x34     |        4 | GPIO interrupt enable for GPIO, level high.                   |
-| gpio.[`INTR_CTRL_EN_LVLLOW`](#intr_ctrl_en_lvllow)         | 0x38     |        4 | GPIO interrupt enable for GPIO, level low.                    |
-| gpio.[`CTRL_EN_INPUT_FILTER`](#ctrl_en_input_filter)       | 0x3c     |        4 | filter enable for GPIO input bits.                            |
-| gpio.[`HW_STRAPS_DATA_IN_VALID`](#hw_straps_data_in_valid) | 0x40     |        4 | Indicates whether the data in !!HW_STRAPS_DATA_IN is valid.   |
-| gpio.[`HW_STRAPS_DATA_IN`](#hw_straps_data_in)             | 0x44     |        4 | GPIO Input data sampled as straps during cold boot read value |
+| Name                                                       | Offset   |   Length | Description                                                                |
+|:-----------------------------------------------------------|:---------|---------:|:---------------------------------------------------------------------------|
+| gpio.[`INTR_STATE`](#intr_state)                           | 0x0      |        4 | Interrupt State Register                                                   |
+| gpio.[`INTR_ENABLE`](#intr_enable)                         | 0x4      |        4 | Interrupt Enable Register                                                  |
+| gpio.[`INTR_TEST`](#intr_test)                             | 0x8      |        4 | Interrupt Test Register                                                    |
+| gpio.[`ALERT_TEST`](#alert_test)                           | 0xc      |        4 | Alert Test Register                                                        |
+| gpio.[`DATA_IN`](#data_in)                                 | 0x10     |        4 | GPIO Input data read value                                                 |
+| gpio.[`DIRECT_OUT`](#direct_out)                           | 0x14     |        4 | GPIO direct output data write value                                        |
+| gpio.[`MASKED_OUT_LOWER`](#masked_out_lower)               | 0x18     |        4 | GPIO write data lower with mask.                                           |
+| gpio.[`MASKED_OUT_UPPER`](#masked_out_upper)               | 0x1c     |        4 | GPIO write data upper with mask.                                           |
+| gpio.[`DIRECT_OE`](#direct_oe)                             | 0x20     |        4 | GPIO Output Enable.                                                        |
+| gpio.[`MASKED_OE_LOWER`](#masked_oe_lower)                 | 0x24     |        4 | GPIO write Output Enable lower with mask.                                  |
+| gpio.[`MASKED_OE_UPPER`](#masked_oe_upper)                 | 0x28     |        4 | GPIO write Output Enable upper with mask.                                  |
+| gpio.[`INTR_CTRL_EN_RISING`](#intr_ctrl_en_rising)         | 0x2c     |        4 | GPIO interrupt enable for GPIO, rising edge.                               |
+| gpio.[`INTR_CTRL_EN_FALLING`](#intr_ctrl_en_falling)       | 0x30     |        4 | GPIO interrupt enable for GPIO, falling edge.                              |
+| gpio.[`INTR_CTRL_EN_LVLHIGH`](#intr_ctrl_en_lvlhigh)       | 0x34     |        4 | GPIO interrupt enable for GPIO, level high.                                |
+| gpio.[`INTR_CTRL_EN_LVLLOW`](#intr_ctrl_en_lvllow)         | 0x38     |        4 | GPIO interrupt enable for GPIO, level low.                                 |
+| gpio.[`CTRL_EN_INPUT_FILTER`](#ctrl_en_input_filter)       | 0x3c     |        4 | filter enable for GPIO input bits.                                         |
+| gpio.[`HW_STRAPS_DATA_IN_VALID`](#hw_straps_data_in_valid) | 0x40     |        4 | Indicates whether the data in !!HW_STRAPS_DATA_IN is valid.                |
+| gpio.[`HW_STRAPS_DATA_IN`](#hw_straps_data_in)             | 0x44     |        4 | GPIO input data that was sampled as straps as the block came out of reset. |
 
 ## INTR_STATE
 Interrupt State Register
@@ -358,7 +358,12 @@ Indicates whether the data in [`HW_STRAPS_DATA_IN`](#hw_straps_data_in) is valid
 |   0    |   ro   |   0x0   | HW_STRAPS_DATA_IN_VALID |               |
 
 ## HW_STRAPS_DATA_IN
-GPIO Input data sampled as straps during cold boot read value
+GPIO input data that was sampled as straps as the block came out of reset.
+
+This register depends on the GpioAsHwStrapsEn parameter.
+- If the parameter is false then the register reads as zero.
+- If the parameter is true then GPIO input data is sampled on the first cycle after reset
+where the strap_en_i input is high. That sampled data is stored in this register.
 - Offset: `0x44`
 - Reset default: `0x0`
 - Reset mask: `0xffffffff`

diff --git a/hw/ip/gpio/dv/env/gpio_env.core b/hw/ip/gpio/dv/env/gpio_env.core
@@ -28,6 +28,7 @@ filesets:
       - seq_lib/gpio_stress_all_vseq.sv: {is_include_file: true}
       - seq_lib/gpio_intr_rand_pgm_vseq.sv: {is_include_file: true}
       - seq_lib/gpio_intr_with_filter_rand_intr_event_vseq.sv: {is_include_file: true}
+      - seq_lib/gpio_rand_straps_vseq.sv : {is_include_file: true}
     file_type: systemVerilogSource
 
 generate:

diff --git a/hw/ip/gpio/dv/env/gpio_env.sv b/hw/ip/gpio/dv/env/gpio_env.sv
@@ -17,6 +17,9 @@ class gpio_env extends cip_base_env #(
     if (!uvm_config_db#(gpio_vif)::get(this, "", "gpio_vif", cfg.gpio_vif)) begin
       `uvm_fatal(get_full_name(), "failed to get gpio_vif from uvm_config_db")
     end
+    if (!uvm_config_db#(straps_vif)::get(this, "", "straps_vif", cfg.straps_vif_inst)) begin
+      `uvm_fatal(get_full_name(), "Virtual interface straps_vif_inst is not set")
+    end
   endfunction
 
 endclass
diff --git a/hw/ip/gpio/dv/env/gpio_env_cfg.sv b/hw/ip/gpio/dv/env/gpio_env_cfg.sv
@@ -13,11 +13,16 @@ class gpio_env_cfg extends cip_base_env_cfg #(
   rand bit pulldown_en;
   // gpio virtual interface
   gpio_vif gpio_vif;
+  // gpio straps interface
+  straps_vif straps_vif_inst;
 
   constraint pullup_pulldown_en_c {pullup_en ^ pulldown_en;}
 
   `uvm_object_utils(gpio_env_cfg)
-  `uvm_object_new
+
+  function new(string name = "gpio_env_cfg");
+    super.new(name);
+  endfunction
 
   virtual function void initialize(bit [TL_AW-1:0] csr_base_addr = '1);
     list_of_alerts = gpio_env_pkg::LIST_OF_ALERTS;
@@ -27,6 +32,9 @@ class gpio_env_cfg extends cip_base_env_cfg #(
 
     // only support 1 outstanding TL item
     m_tl_agent_cfg.max_outstanding_req = 1;
+
+    // Used to allow reset operation during a stress all tests and check the CSR after that.
+    can_reset_with_csr_accesses = 1'b1;
   endfunction : initialize
 
 endclass
diff --git a/hw/ip/gpio/dv/env/gpio_env_pkg.sv b/hw/ip/gpio/dv/env/gpio_env_pkg.sv
@@ -27,6 +27,7 @@ package gpio_env_pkg;
   parameter string LIST_OF_ALERTS[] = {"fatal_fault"};
 
   typedef virtual pins_if #(NUM_GPIOS) gpio_vif;
+  typedef virtual gpio_straps_if straps_vif;
   typedef class gpio_env_cfg;
   typedef class gpio_env_cov;
   typedef cip_base_virtual_sequencer #(gpio_env_cfg, gpio_env_cov) gpio_virtual_sequencer;

diff --git a/hw/ip/gpio/dv/env/gpio_scoreboard.sv b/hw/ip/gpio/dv/env/gpio_scoreboard.sv
@@ -31,6 +31,8 @@ class gpio_scoreboard extends cip_base_scoreboard #(.CFG_T (gpio_env_cfg),
   //  (i) indicate that write to INTR_STATE register just happened, and
   // (ii) store information of which all interupt bits were cleared
   bit [TL_DW-1:0] cleared_intr_bits;
+  // Flag to indicate that the strap was triggered
+  bit first_strap_triggered;
 
   // mask are WO, store the values in scb
   uvm_reg_data_t masked_out_lower_mask;
@@ -40,7 +42,9 @@ class gpio_scoreboard extends cip_base_scoreboard #(.CFG_T (gpio_env_cfg),
 
   `uvm_component_utils(gpio_scoreboard)
 
-  `uvm_component_new
+  function new (string name = "gpio_scoreboard", uvm_component parent = null);
+    super.new (name, parent);
+  endfunction
 
   // Function: build_phase
   function void build_phase(uvm_phase phase);
@@ -54,6 +58,8 @@ class gpio_scoreboard extends cip_base_scoreboard #(.CFG_T (gpio_env_cfg),
     fork
       monitor_gpio_i();
       monitor_gpio_interrupt_pins();
+      monitor_gpio_straps();
+      handle_reset();
     join_none
   endtask
 
@@ -360,6 +366,46 @@ class gpio_scoreboard extends cip_base_scoreboard #(.CFG_T (gpio_env_cfg),
     end
   endtask : monitor_gpio_interrupt_pins
 
+  // Task: monitor_gpio_straps
+  virtual task monitor_gpio_straps();
+    forever begin : monitor_gpio_intr
+      @(posedge cfg.clk_rst_vif.clk)
+      if(!cfg.under_reset) begin
+        if (|gpio_i_driven === 1'b1) begin
+          @(negedge cfg.straps_vif_inst.strap_en) begin
+            if (!first_strap_triggered) begin
+              // Update data_in ral register value based on result of input
+              `DV_CHECK_FATAL(
+                ral.hw_straps_data_in.predict(.value(gpio_i_driven),
+                                              .kind(UVM_PREDICT_DIRECT)));
+              // Update data_in valid register value based on result of input
+              `DV_CHECK_FATAL(
+                ral.hw_straps_data_in_valid.predict(.value('b1),
+                                                    .kind(UVM_PREDICT_DIRECT)));
+
+              // Checker: Compare actual values of gpio pins with straps register.
+              // Check the register hw_straps_data_in against gpio_i pins
+              `DV_CHECK_CASE_EQ(gpio_i_driven, cfg.straps_vif_inst.sampled_straps.data)
+              // Check the register hw_straps_data_in_valid
+              `DV_CHECK_CASE_EQ('b1, cfg.straps_vif_inst.sampled_straps.valid)
+              // Turn-off the checker after the first strap trigger.
+              first_strap_triggered = 1;                                   
+            end
+          end
+        end
+      end
+    end
+  endtask : monitor_gpio_straps
+
+  virtual protected task handle_reset();
+    forever begin
+      @(negedge cfg.clk_rst_vif.rst_n);
+      cfg.under_reset = 1;
+      @(posedge cfg.clk_rst_vif.rst_n);
+      cfg.under_reset = 0;
+    end
+  endtask
+
   // Function: actual_gpio_i_activity
   function bit actual_gpio_i_activity();
     return ~((prv_gpio_i_pins_o === cfg.gpio_vif.pins_o) &&
@@ -561,6 +607,7 @@ class gpio_scoreboard extends cip_base_scoreboard #(.CFG_T (gpio_env_cfg),
           ((|gpio_i_driven === 1'b1) && (actual_gpio_i_activity() == 1))) begin
         `DV_CHECK_CASE_EQ(pred_val_gpio_pins, cfg.gpio_vif.pins)
       end
+
     end
 
   endfunction : gpio_predict_and_compare
@@ -804,6 +851,7 @@ class gpio_scoreboard extends cip_base_scoreboard #(.CFG_T (gpio_env_cfg),
     last_intr_update_except_clearing = '0;
     last_intr_test_event = '0;
     cleared_intr_bits = '0;
+    first_strap_triggered = 0;
   endfunction
 
   // Function: check_phase