ioport: Restore PIN to PORT values when DDR is set to output

[simavr] / simavr / sim / avr_ioport.c

diff --git a/simavr/sim/avr_ioport.c b/simavr/sim/avr_ioport.c
index be30652..24a8a9b 100644 (file)
--- a/simavr/sim/avr_ioport.c
+++ b/simavr/sim/avr_ioport.c
@@ -38,19 +38,14 @@ static uint8_t avr_ioport_read(struct avr_t * avr, avr_io_addr_t addr, void * pa
 static void avr_ioport_write(struct avr_t * avr, avr_io_addr_t addr, uint8_t v, void * param)
 {
        avr_ioport_t * p = (avr_ioport_t *)param;
-       uint8_t oldv = avr->data[addr];
 
        avr_core_watch_write(avr, addr, v);
-       if (v != oldv) {
-               //      printf("PORT%c(%02x) = %02x (was %02x)\n", p->name, addr, v, oldv);
-               int mask = v ^ oldv;
-
-               // raise the internal IRQ callbacks
-               for (int i = 0; i < 8; i++)
-                       if (mask & (1 << i))
-                               avr_raise_irq(p->io.irq + i, (v >> i) & 1);
-               avr_raise_irq(p->io.irq + IOPORT_IRQ_PIN_ALL, v);
-       }
+       //      printf("PORT%c(%02x) = %02x (was %02x)\n", p->name, addr, v, oldv);
+
+       // raise the internal IRQ callbacks
+       for (int i = 0; i < 8; i++)
+               avr_raise_irq(p->io.irq + i, (v >> i) & 1);
+       avr_raise_irq(p->io.irq + IOPORT_IRQ_PIN_ALL, v);
 }
 
 /*
@@ -64,6 +59,27 @@ static void avr_ioport_pin_write(struct avr_t * avr, avr_io_addr_t addr, uint8_t
        avr_ioport_write(avr, p->r_port, avr->data[p->r_port] ^ v, param);
 }
 
+/*
+ * This is a the callback for the DDR register. There is nothing much to do here, apart
+ * from triggering an IRQ in case any 'client' code is interested in the information,
+ * and restoring all PIN bits marked as output to PORT values.
+ */
+static void avr_ioport_ddr_write(struct avr_t * avr, avr_io_addr_t addr, uint8_t v, void * param)
+{
+       avr_ioport_t * p = (avr_ioport_t *)param;
+
+       avr_raise_irq(p->io.irq + IOPORT_IRQ_DIRECTION_ALL, v);
+       avr_core_watch_write(avr, addr, v);
+
+       const uint8_t oldpin = avr->data[p->r_pin];
+       const uint8_t pin = (oldpin & ~v) | (avr->data[p->r_port] & v);
+       avr_core_watch_write(avr, p->r_pin, pin);
+       for (int i = 0; i < 8; i++)
+               if (((oldpin ^ pin) >> i) & 1)
+                       avr_raise_irq(p->io.irq + i, (pin >> i) & 1);
+       avr_raise_irq(p->io.irq + IOPORT_IRQ_PIN_ALL, pin);
+}
+
 /*
  * this is our "main" pin change callback, it can be triggered by either the
  * AVR code, or any external piece of code that see fit to do it.
@@ -74,7 +90,7 @@ void avr_ioport_irq_notify(struct avr_irq_t * irq, uint32_t value, void * param)
        avr_ioport_t * p = (avr_ioport_t *)param;
        avr_t * avr = p->io.avr;
 
-       int output = value & 0x100;
+       int output = value & AVR_IOPORT_OUTPUT;
        value &= 0xff;
        uint8_t mask = 1 << irq->irq;
                // set the real PIN bit. ddr doesn't matter here as it's masked when read.
@@ -116,7 +132,7 @@ static int avr_ioport_ioctl(struct avr_io_t * port, uint32_t ctl, void * io_para
                                if (r->bit.mask == 0xff)
                                        r->irq[o++] = &p->io.irq[IOPORT_IRQ_PIN_ALL];
                                else {
-                                       // otherwise fil up the ones needed
+                                       // otherwise fill up the ones needed
                                        for (int bi = 0; bi < 8; bi++)
                                                if (r->bit.mask & (1 << bi))
                                                        r->irq[o++] = &p->io.irq[r->bit.bit + bi];
@@ -147,10 +163,24 @@ static int avr_ioport_ioctl(struct avr_io_t * port, uint32_t ctl, void * io_para
        return res;
 }
 
+static const char * irq_names[IOPORT_IRQ_COUNT] = {
+       [IOPORT_IRQ_PIN0] = "=pin0",
+       [IOPORT_IRQ_PIN1] = "=pin1",
+       [IOPORT_IRQ_PIN2] = "=pin2",
+       [IOPORT_IRQ_PIN3] = "=pin3",
+       [IOPORT_IRQ_PIN4] = "=pin4",
+       [IOPORT_IRQ_PIN5] = "=pin5",
+       [IOPORT_IRQ_PIN6] = "=pin6",
+       [IOPORT_IRQ_PIN7] = "=pin7",
+       [IOPORT_IRQ_PIN_ALL] = "=all",
+       [IOPORT_IRQ_DIRECTION_ALL] = ">ddr",
+};
+
 static avr_io_t        _io = {
-       .kind = "io",
+       .kind = "port",
        .reset = avr_ioport_reset,
        .ioctl = avr_ioport_ioctl,
+       .irq_names = irq_names,
 };
 
 void avr_ioport_init(avr_t * avr, avr_ioport_t * p)
@@ -160,17 +190,18 @@ void avr_ioport_init(avr_t * avr, avr_ioport_t * p)
 //             p->name, p->r_pin,
 //             p->name, p->r_ddr,
 //             p->name, p->r_port);
-
-       // allocate this module's IRQ
-       p->io.irq_count = IOPORT_IRQ_COUNT;
-       p->io.irq = avr_alloc_irq(0, p->io.irq_count);
-       p->io.irq_ioctl_get = AVR_IOCTL_IOPORT_GETIRQ(p->name);
        
        avr_register_io(avr, &p->io);
        avr_register_vector(avr, &p->pcint);
+       // allocate this module's IRQ
+       avr_io_setirqs(&p->io, AVR_IOCTL_IOPORT_GETIRQ(p->name), IOPORT_IRQ_COUNT, NULL);
+
+       for (int i = 0; i < IOPORT_IRQ_COUNT; i++)
+               p->io.irq[i].flags |= IRQ_FLAG_FILTERED;
 
        avr_register_io_write(avr, p->r_port, avr_ioport_write, p);
        avr_register_io_read(avr, p->r_pin, avr_ioport_read, p);
        avr_register_io_write(avr, p->r_pin, avr_ioport_pin_write, p);
+       avr_register_io_write(avr, p->r_ddr, avr_ioport_ddr_write, p);
 }