Generate GPIF WAVEDATA on demand

diff --git a/gpif-acquisition.c b/gpif-acquisition.c
index 9eedfbfdea988f8eca5e6d3a3cf4f24b337d0641..44adc26ea846c9e28def27e1893bd38259fd53f4 100644 (file)
--- a/gpif-acquisition.c
+++ b/gpif-acquisition.c
@@ -27,93 +27,17 @@
 #include <fx2lafw.h>
 #include <gpif-acquisition.h>
 
-/* GPIF terminology: DP = decision point, NDP = non-decision-point */
-
-/*
- * GPIF waveforms.
- *
- * See section "10.3.4 State Instructions" in the TRM for details.
- */
-static const BYTE wavedata[128] = {
-       /* Waveform 0: */
-
-       /*
-        * This is the basic algorithm implemented in our GPIF state machine:
-        *
-        * State 0: NDP: Sample the FIFO data bus.
-        * State 1: DP: If EP2 is full, go to state 7 (the IDLE state), i.e.,
-        *          end the current waveform. Otherwise, go to state 0 again,
-        *          i.e., sample data until EP2 is full.
-        * State 2: Unused.
-        * State 3: Unused.
-        * State 4: Unused.
-        * State 5: Unused.
-        * State 6: Unused.
-        */
-
-       /* S0-S6: LENGTH/BRANCH */
-       /*
-        * For NDPs (LENGTH): Number of IFCLK cycles to stay in this state.
-        * For DPs (BRANCH): [7] ReExec, [5:3]: BRANCHON1, [2:0]: BRANCHON0.
-        *
-        * 0x01: Stay one IFCLK cycle in this state.
-        * 0x38: No Re-execution, BRANCHON1 = state 7, BRANCHON0 = state 0.
-        */
-       // 0x01, 0x38, 0x01, 0x01, 0x01, 0x01, 0x01,
-       // FIXME: For now just loop over the "sample data" state forever.
-       0x01, 0x00, 0x01, 0x01, 0x01, 0x01, 0x01,
-       /* TRM says "reserved", but GPIF designer always puts a 0x07 here. */
-       0x07,
-
-       /* S0-S6: OPCODE */
-       /*
-        * 0x02: NDP, sample the FIFO data bus.
-        * 0x01: DP, don't sample the FIFO data bus.
-        */
-       0x02, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00,
-       /* Reserved */
-       0x00,
-
-       /* S0-S6: OUTPUT */
-       /* Unused, we don't output anything, we only sample the pins. */
-       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-       /* Reserved */
-       0x00,
+static void gpif_reset_waveforms(void)
+{
+       int i;
 
-       /* S0-S6: LOGIC FUNCTION (not used for NDPs) */
-       /*
-        * 0x36: LFUNC = "A AND B", A = FIFO flag, B = FIFO flag.
-        * The FIFO flag (FF == full flag, in our case) is configured via
-        * EP2GPIFFLGSEL.
-        *
-        * So: If the EP2 FIFO is full and the EP2 FIFO is full, go to
-        * the state specified by BRANCHON1 (state 7), otherwise BRANCHON0
-        * (state 0). See the LENGTH/BRANCH value above for details.
-        */
-       0x00, 0x36, 0x00, 0x00, 0x00, 0x00, 0x00,
-       /* TRM says "reserved", but GPIF designer always puts a 0x3f here. */
-       0x3f,
-
-       /* TODO: Must unused waveforms be "valid"? */
-
-       /* Waveform 1 (unused): */
-       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-
-       /* Waveform 2 (unused): */
-       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-
-       /* Waveform 3 (unused): */
-       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-};
+       /* Reset WAVEDATA. */
+       AUTOPTRSETUP = 0x03;
+       AUTOPTRH1 = 0xe4;
+       AUTOPTRL1 = 0x00;
+       for (i = 0; i < 128; i++)
+               EXTAUTODAT1 = 0;
+}
 
 static void gpif_setup_registers(void)
 {
@@ -134,7 +58,7 @@ static void gpif_setup_registers(void)
        GPIFIDLECTL = 0;
 
        /*
-        * Map index 0 in wavedata[] to FIFORD. The rest is assigned too,
+        * Map index 0 in WAVEDATA to FIFORD. The rest is assigned too,
         * but not used by us.
         *
         * GPIFWFSELECT: [7:6] = SINGLEWR index, [5:4] = SINGLERD index,
@@ -146,23 +70,6 @@ static void gpif_setup_registers(void)
        GPIFREADYSTAT = 0;
 }
 
-static void gpif_write_waveforms(void)
-{
-       int i;
-
-       /*
-        * Write the four waveforms into the respective WAVEDATA register
-        * locations (0xe400 - 0xe47f) using the FX2's autopointer feature.
-        */
-       AUTOPTRSETUP = 0x07;             /* Increment autopointers 1 & 2. */
-       AUTOPTRH1 = MSB((WORD)wavedata); /* Source is the 'wavedata' array. */
-       AUTOPTRL1 = LSB((WORD)wavedata);
-       AUTOPTRH2 = 0xe4;                /* Dest is WAVEDATA (0xe400). */
-       AUTOPTRL2 = 0x00;
-       for (i = 0; i < 128; i++)
-               EXTAUTODAT2 = EXTAUTODAT1;
-}
-
 static void gpif_init_addr_pins(void)
 {
        /*
@@ -207,8 +114,8 @@ void gpif_init_la(void)
        /* Setup the GPIF registers. */
        gpif_setup_registers();
 
-       /* Write the four GPIF waveforms into the WAVEDATA register. */
-       gpif_write_waveforms();
+       /* Reset WAVEDATA. */
+       gpif_reset_waveforms();
 
        /* Initialize GPIF address pins, output initial values. */
        gpif_init_addr_pins();
@@ -219,6 +126,48 @@ void gpif_init_la(void)
 
 void gpif_acquisition_start(void)
 {
+       xdata volatile BYTE *pSTATE;
+
+       /* GPIF terminology: DP = decision point, NDP = non-decision-point */
+
+       /* Populate WAVEDATA
+        *
+        * This is the basic algorithm implemented in our GPIF state machine:
+        *
+        * State 0: NDP: Sample the FIFO data bus.
+        * State 1: DP: If EP2 is full, go to state 7 (the IDLE state), i.e.,
+        *          end the current waveform. Otherwise, go to state 0 again,
+        *          i.e., sample data until EP2 is full.
+        * State 2: Unused.
+        * State 3: Unused.
+        * State 4: Unused.
+        * State 5: Unused.
+        * State 6: Unused.
+        */
+
+       /* Populate S0 */
+       pSTATE = &GPIF_WAVE_DATA;
+       pSTATE[0] = 0x01;
+       pSTATE[8] = 0x02;
+       pSTATE[16] = 0x00;
+       pSTATE[24] = 0x00;
+
+       /* Populate S1 */
+       pSTATE = &GPIF_WAVE_DATA + 1;
+       pSTATE[0] = 0x00;
+       pSTATE[8] = 0x01;
+       pSTATE[16] = 0x00;
+       pSTATE[24] = 0x36;
+
+       /* Populate Reserved Words */
+       pSTATE = &GPIF_WAVE_DATA + 7;
+       pSTATE[0] = 0x07;
+       pSTATE[8] = 0x00;
+       pSTATE[16] = 0x00;
+       pSTATE[24] = 0x3f;
+
+       SYNCDELAY();
+
        /* Perform the initial GPIF read. */
        gpif_fifo_read(GPIF_EP2);
 }