FF.CFG: New option ungated= to ignore the drive-select line

Instead the drive is permanently enabled.

examples/FF.CFG

@@ -102,6 +102,11 @@ motor-delay = ignore
 # delay-N: Automatically after N*0.5sec (0 <= N <= 15)
 chgrst = step
 
+# Ungated mode: If yes, this drive is permanently enabled, its outputs are
+# constantly active, and jumper locations S0/S1/MO have no effect.
+# Values: yes | no
+ungated = no
+
 ##
 ## STARTUP / INITIALISATION
 

inc/config.h

@@ -164,6 +164,7 @@ struct packed ff_cfg {
 #define WDRAIN_eot      2
     uint8_t write_drain;
     uint8_t max_cyl;
+    bool_t ungated;
 };
 
 extern struct ff_cfg ff_cfg;

src/floppy.c

@@ -285,8 +285,17 @@ static void drive_configure_output_pin(unsigned int pin)
 
 void floppy_init(void)
 {
+    const struct exti_irq *irqs;
     struct drive *drv = &drive;
 
+    irqs = exti_irqs;
+    if (ff_cfg.ungated) {
+        /* Skip initialisation of SELA IRQ. We ignore SELA and permanently
+         * enable drive select. */
+        irqs += 1;
+        drv->sel = 1;
+    }
+
     floppy_set_fintf_mode();
 
     board_floppy_init();
@@ -305,7 +314,7 @@ void floppy_init(void)
     drive_change_output(drv, outp_wrprot, TRUE);
     drive_change_output(drv, outp_trk0,   TRUE);
 
-    floppy_init_irqs();
+    floppy_init_irqs(irqs);
 
     IRQx_set_prio(FLOPPY_SOFTIRQ, FLOPPY_SOFTIRQ_PRI);
     IRQx_enable(FLOPPY_SOFTIRQ);

src/floppy_generic.c

@@ -97,14 +97,13 @@ struct exti_irq {
 #include "gotek/floppy.c"
 #endif
 
-/* Initialise IRQs according to statically-defined exti_irqs[]. */
+/* Initialise the specified list of IRQs. */
-static void floppy_init_irqs(void)
+static void floppy_init_irqs(const struct exti_irq *irqs)
 {
     const struct exti_irq *e;
-    unsigned int i;
 
     /* Configure physical interface interrupts. */
-    for (i = 0, e = exti_irqs; i < ARRAY_SIZE(exti_irqs); i++, e++) {
+    for (e = irqs; e->irq != 0; e++) {
         IRQx_set_prio(e->irq, e->pri);
         if (e->pr_mask != 0) {
             /* Do not trigger an initial interrupt on this line. Clear EXTI_PR
@@ -120,7 +119,7 @@ static void floppy_init_irqs(void)
     }
 
     /* Enable physical interface interrupts. */
-    for (i = 0, e = exti_irqs; i < ARRAY_SIZE(exti_irqs); i++, e++) {
+    for (e = irqs; e->irq != 0; e++) {
         IRQx_enable(e->irq);
     }
 }

src/gotek/floppy.c

@@ -60,7 +60,8 @@ static const struct exti_irq exti_irqs[] = {
     /* WGATE */ {  7, FLOPPY_IRQ_WGATE_PRI, 0 },
     /* SIDE */ { 10, TIMER_IRQ_PRI, 0 }, 
     /* WGATE */ { 23, FLOPPY_IRQ_WGATE_PRI, 0 },
-    /* MTR/CHGRST */ { 40, TIMER_IRQ_PRI, 0 }
+    /* MTR/CHGRST */ { 40, TIMER_IRQ_PRI, 0 },
+    { 0, 0, 0 }
 };
 
 /* Subset of output pins which are active (O_TRUE). */

src/gotek/quickdisk.c

@@ -57,7 +57,8 @@ static const struct exti_irq exti_irqs[] = {
     /* WGATE */ { 7, FLOPPY_IRQ_WGATE_PRI, 0 },
     /* WGATE */ { 23, FLOPPY_IRQ_WGATE_PRI, 0 },
     /* RESET */ { 28, TIMER_IRQ_PRI, 0 },
-    /* Rotary */ { 40, TIMER_IRQ_PRI, 0 }
+    /* Rotary */ { 40, TIMER_IRQ_PRI, 0 },
+    { 0, 0, 0 }
 };
 
 bool_t floppy_ribbon_is_reversed(void)

src/main.c

@@ -1038,6 +1038,10 @@ static void read_ff_cfg(void)
                 : CHGRST_step;
             break;
 
+        case FFCFG_ungated:
+            ff_cfg.ungated = !strcmp(opts.arg, "yes");
+            break;
+
             /* STARTUP / INITIALISATION */
 
         case FFCFG_ejected_on_startup:
@@ -1304,9 +1308,11 @@ static void process_ff_cfg_opts(const struct ff_cfg *old)
         cfg.ejected = TRUE;
 
     /* oled-font, display-type: Reinitialise the display subsystem. */
+    /* ungated: Reinitialise the floppy subsystem. */
     if ((ff_cfg.oled_font != old->oled_font)
         || (ff_cfg.oled_contrast != old->oled_contrast)
-        || (ff_cfg.display_type != old->display_type))
+        || (ff_cfg.display_type != old->display_type)
+        || (ff_cfg.ungated != old->ungated))
         system_reset(); /* hit it with a hammer */
 }
 

src/quickdisk.c

@@ -138,7 +138,7 @@ void floppy_init(void)
     write_pin(wrprot, HIGH);
     write_pin(ready,  HIGH);
 
-    floppy_init_irqs();
+    floppy_init_irqs(exti_irqs);
 
     timer_init(&index.timer, index_assert, NULL);
 }