RP.PIO: allow non-blocking put/get on FIFOs

Also add FIFO status functions.
JeremyGrosser · Feb 29, 2024 · 71f589d · 71f589d
1 parent 70984e0
commit 71f589d
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diff --git a/src/drivers/rp-pio.adb b/src/drivers/rp-pio.adb
@@ -407,6 +407,19 @@ package body RP.PIO is
       end loop;
    end Put;
 
+   procedure Try_Put
+     (This    : in out PIO_Device;
+      SM      : PIO_SM;
+      Data    : UInt32;
+      Success : out Boolean)
+   is
+   begin
+      Success := not This.TX_FIFO_Full (SM);
+      if Success then
+         This.Periph.TXF (SM) := Data;
+      end if;
+   end Try_Put;
+
    procedure Get
       (This : in out PIO_Device;
        SM   : PIO_SM;
@@ -433,6 +446,31 @@ package body RP.PIO is
       end loop;
    end Get;
 
+   procedure Try_Get
+      (This    : in out PIO_Device;
+       SM      : PIO_SM;
+       Data    : out UInt32;
+       Success : out Boolean)
+   is
+   begin
+      Success := not This.RX_FIFO_Empty (SM);
+      if Success then
+         Data := This.Periph.RXF (SM);
+      end if;
+   end Try_Get;
+
+   function RX_FIFO_Full (This : PIO_Device; SM : PIO_SM) return Boolean
+   is (This.Periph.FSTAT.RXFULL (SM));
+
+   function RX_FIFO_Empty (This : PIO_Device; SM : PIO_SM) return Boolean
+   is (This.Periph.FSTAT.RXEMPTY (SM));
+
+   function TX_FIFO_Full (This : PIO_Device; SM : PIO_SM) return Boolean
+   is (This.Periph.FSTAT.TXFULL (SM));
+
+   function TX_FIFO_Empty (This : PIO_Device; SM : PIO_SM) return Boolean
+   is (This.Periph.FSTAT.TXEMPTY (SM));
+
    function TX_FIFO_Address
       (This : PIO_Device;
        SM   : PIO_SM)

diff --git a/src/drivers/rp-pio.ads b/src/drivers/rp-pio.ads
@@ -182,21 +182,51 @@ is
       (This : in out PIO_Device;
        SM   : PIO_SM;
        Data : UInt32);
+   --  Put one word in the TX FIFO of the given state machine. If the FIFO is
+   --  full, this call will run a buzy loop until there's room for the data.
 
    procedure Put
       (This : in out PIO_Device;
        SM   : PIO_SM;
        Data : UInt32_Array);
+   --  Put data in the TX FIFO of the given state machine. If the FIFO is
+   --  full, this call will run a buzy loop until there's room for the data.
+
+   procedure Try_Put
+      (This    : in out PIO_Device;
+       SM      : PIO_SM;
+       Data    : UInt32;
+       Success : out Boolean);
+   --  Try to put one word in the TX FIFO of the given state machine. If the
+   --  FIFO is full, Success is set to False and the data not transmitted.
 
    procedure Get
       (This : in out PIO_Device;
        SM   : PIO_SM;
        Data : out UInt32);
+   --  Get one word from the RX FIFO of the given state machine. If the FIFO
+   --  is empty, this call will run a buzy loop until there's data available.
 
    procedure Get
       (This : in out PIO_Device;
        SM   : PIO_SM;
        Data : out UInt32_Array);
+   --  Get data from the RX FIFO of the given state machine. If the FIFO is
+   --  empty, this call will run a buzy loop until there's data available.
+
+   procedure Try_Get
+      (This    : in out PIO_Device;
+       SM      : PIO_SM;
+       Data    : out UInt32;
+       Success : out Boolean);
+   --  Try to get one word from the RX FIFO of the given state machine. If the
+   --  FIFO is empty, Success is set to False and Data is not set.
+
+   function RX_FIFO_Full (This : PIO_Device; SM : PIO_SM) return Boolean;
+   function RX_FIFO_Empty (This : PIO_Device; SM : PIO_SM) return Boolean;
+
+   function TX_FIFO_Full (This : PIO_Device; SM : PIO_SM) return Boolean;
+   function TX_FIFO_Empty (This : PIO_Device; SM : PIO_SM) return Boolean;
 
    function TX_FIFO_Address
       (This : PIO_Device;