hw/m68k/q800-glue.c - qemu - Git at Google

 /*
  * QEMU q800 logic GLUE (General Logic Unit)
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
  *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */

 #include "qemu/osdep.h"
 #include "cpu.h"
 #include "hw/m68k/q800-glue.h"
 #include "hw/boards.h"
 #include "hw/irq.h"
 #include "hw/nmi.h"
 #include "hw/qdev-properties.h"
 #include "migration/vmstate.h"

 /*
  * The GLUE (General Logic Unit) is an Apple custom integrated circuit chip
  * that performs a variety of functions (RAM management, clock generation, ...).
  * The GLUE chip receives interrupt requests from various devices,
  * assign priority to each, and asserts one or more interrupt line to the
  * CPU.
  */

 /*
  * The GLUE logic on the Quadra 800 supports 2 different IRQ routing modes
  * controlled from the VIA1 auxmode GPIO (port B bit 6) which are documented
  * in NetBSD as follows:
  *
  * A/UX mode (Linux, NetBSD, auxmode GPIO low)
  *
  *   Level 0:        Spurious: ignored
  *   Level 1:        Software
  *   Level 2:        VIA2 (except ethernet, sound)
  *   Level 3:        Ethernet
  *   Level 4:        Serial (SCC)
  *   Level 5:        Sound
  *   Level 6:        VIA1
  *   Level 7:        NMIs: parity errors, RESET button, YANCC error
  *
  * Classic mode (default: used by MacOS, A/UX 3.0.1, auxmode GPIO high)
  *
  *   Level 0:        Spurious: ignored
  *   Level 1:        VIA1 (clock, ADB)
  *   Level 2:        VIA2 (NuBus, SCSI)
  *   Level 3:
  *   Level 4:        Serial (SCC)
  *   Level 5:
  *   Level 6:
  *   Level 7:        Non-maskable: parity errors, RESET button
  *
  * Note that despite references to A/UX mode in Linux and NetBSD, at least
  * A/UX 3.0.1 still uses Classic mode.
  */

 static void GLUE_set_irq(void *opaque, int irq, int level)
 {
     GLUEState *s = opaque;
     int i;

     if (s->auxmode) {
         /* Classic mode */
         switch (irq) {
         case GLUE_IRQ_IN_VIA1:
             irq = 0;
             break;

         case GLUE_IRQ_IN_VIA2:
             irq = 1;
             break;

         case GLUE_IRQ_IN_SONIC:
             /* Route to VIA2 instead */
             qemu_set_irq(s->irqs[GLUE_IRQ_NUBUS_9], level);
             return;

         case GLUE_IRQ_IN_ESCC:
             irq = 3;
             break;

         case GLUE_IRQ_IN_NMI:
             irq = 6;
             break;

         default:
             g_assert_not_reached();
         }
     } else {
         /* A/UX mode */
         switch (irq) {
         case GLUE_IRQ_IN_VIA1:
             irq = 5;
             break;

         case GLUE_IRQ_IN_VIA2:
             irq = 1;
             break;

         case GLUE_IRQ_IN_SONIC:
             irq = 2;
             break;

         case GLUE_IRQ_IN_ESCC:
             irq = 3;
             break;

         case GLUE_IRQ_IN_NMI:
             irq = 6;
             break;

         default:
             g_assert_not_reached();
         }
     }

     if (level) {
         s->ipr |= 1 << irq;
     } else {
         s->ipr &= ~(1 << irq);
     }

     for (i = 7; i >= 0; i--) {
         if ((s->ipr >> i) & 1) {
             m68k_set_irq_level(s->cpu, i + 1, i + 25);
             return;
         }
     }
     m68k_set_irq_level(s->cpu, 0, 0);
 }

 static void glue_auxmode_set_irq(void *opaque, int irq, int level)
 {
     GLUEState *s = GLUE(opaque);

     s->auxmode = level;
 }

 static void glue_nmi(NMIState *n, int cpu_index, Error **errp)
 {
     GLUEState *s = GLUE(n);

     /* Hold NMI active for 100ms */
     GLUE_set_irq(s, GLUE_IRQ_IN_NMI, 1);
     timer_mod(s->nmi_release, qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL) + 100);
 }

 static void glue_nmi_release(void *opaque)
 {
     GLUEState *s = GLUE(opaque);

     GLUE_set_irq(s, GLUE_IRQ_IN_NMI, 0);
 }

 static void glue_reset(DeviceState *dev)
 {
     GLUEState *s = GLUE(dev);

     s->ipr = 0;
     s->auxmode = 0;

     timer_del(s->nmi_release);
 }

 static const VMStateDescription vmstate_glue = {
     .name = "q800-glue",
     .version_id = 0,
     .minimum_version_id = 0,
     .fields = (VMStateField[]) {
         VMSTATE_UINT8(ipr, GLUEState),
         VMSTATE_UINT8(auxmode, GLUEState),
         VMSTATE_TIMER_PTR(nmi_release, GLUEState),
         VMSTATE_END_OF_LIST(),
     },
 };

 /*
  * If the m68k CPU implemented its inbound irq lines as GPIO lines
  * rather than via the m68k_set_irq_level() function we would not need
  * this cpu link property and could instead provide outbound IRQ lines
  * that the board could wire up to the CPU.
  */
 static Property glue_properties[] = {
     DEFINE_PROP_LINK("cpu", GLUEState, cpu, TYPE_M68K_CPU, M68kCPU *),
     DEFINE_PROP_END_OF_LIST(),
 };

 static void glue_finalize(Object *obj)
 {
     GLUEState *s = GLUE(obj);

     timer_free(s->nmi_release);
 }

 static void glue_init(Object *obj)
 {
     DeviceState *dev = DEVICE(obj);
     GLUEState *s = GLUE(dev);

     qdev_init_gpio_in(dev, GLUE_set_irq, 8);
     qdev_init_gpio_in_named(dev, glue_auxmode_set_irq, "auxmode", 1);

     qdev_init_gpio_out(dev, s->irqs, 1);

     /* NMI release timer */
     s->nmi_release = timer_new_ms(QEMU_CLOCK_VIRTUAL, glue_nmi_release, s);
 }

 static void glue_class_init(ObjectClass *klass, void *data)
 {
     DeviceClass *dc = DEVICE_CLASS(klass);
     NMIClass *nc = NMI_CLASS(klass);

     dc->vmsd = &vmstate_glue;
     dc->reset = glue_reset;
     device_class_set_props(dc, glue_properties);
     nc->nmi_monitor_handler = glue_nmi;
 }

 static const TypeInfo glue_info_types[] = {
     {
         .name = TYPE_GLUE,
         .parent = TYPE_SYS_BUS_DEVICE,
         .instance_size = sizeof(GLUEState),
         .instance_init = glue_init,
         .instance_finalize = glue_finalize,
         .class_init = glue_class_init,
         .interfaces = (InterfaceInfo[]) {
              { TYPE_NMI },
              { }
         },
     },
 };

 DEFINE_TYPES(glue_info_types)
	/*
	* QEMU q800 logic GLUE (General Logic Unit)
	*
	* Permission is hereby granted, free of charge, to any person obtaining a copy
	* of this software and associated documentation files (the "Software"), to deal
	* in the Software without restriction, including without limitation the rights
	* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
	* copies of the Software, and to permit persons to whom the Software is
	* furnished to do so, subject to the following conditions:
	*
	* The above copyright notice and this permission notice shall be included in
	* all copies or substantial portions of the Software.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
	* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
	* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
	* THE SOFTWARE.
	*/

	#include "qemu/osdep.h"
	#include "cpu.h"
	#include "hw/m68k/q800-glue.h"
	#include "hw/boards.h"
	#include "hw/irq.h"
	#include "hw/nmi.h"
	#include "hw/qdev-properties.h"
	#include "migration/vmstate.h"

	/*
	* The GLUE (General Logic Unit) is an Apple custom integrated circuit chip
	* that performs a variety of functions (RAM management, clock generation, ...).
	* The GLUE chip receives interrupt requests from various devices,
	* assign priority to each, and asserts one or more interrupt line to the
	* CPU.
	*/

	/*
	* The GLUE logic on the Quadra 800 supports 2 different IRQ routing modes
	* controlled from the VIA1 auxmode GPIO (port B bit 6) which are documented
	* in NetBSD as follows:
	*
	* A/UX mode (Linux, NetBSD, auxmode GPIO low)
	*
	* Level 0: Spurious: ignored
	* Level 1: Software
	* Level 2: VIA2 (except ethernet, sound)
	* Level 3: Ethernet
	* Level 4: Serial (SCC)
	* Level 5: Sound
	* Level 6: VIA1
	* Level 7: NMIs: parity errors, RESET button, YANCC error
	*
	* Classic mode (default: used by MacOS, A/UX 3.0.1, auxmode GPIO high)
	*
	* Level 0: Spurious: ignored
	* Level 1: VIA1 (clock, ADB)
	* Level 2: VIA2 (NuBus, SCSI)
	* Level 3:
	* Level 4: Serial (SCC)
	* Level 5:
	* Level 6:
	* Level 7: Non-maskable: parity errors, RESET button
	*
	* Note that despite references to A/UX mode in Linux and NetBSD, at least
	* A/UX 3.0.1 still uses Classic mode.
	*/

	static void GLUE_set_irq(void *opaque, int irq, int level)
	{
	GLUEState *s = opaque;
	int i;

	if (s->auxmode) {
	/* Classic mode */
	switch (irq) {
	case GLUE_IRQ_IN_VIA1:
	irq = 0;
	break;

	case GLUE_IRQ_IN_VIA2:
	irq = 1;
	break;

	case GLUE_IRQ_IN_SONIC:
	/* Route to VIA2 instead */
	qemu_set_irq(s->irqs[GLUE_IRQ_NUBUS_9], level);
	return;

	case GLUE_IRQ_IN_ESCC:
	irq = 3;
	break;

	case GLUE_IRQ_IN_NMI:
	irq = 6;
	break;

	default:
	g_assert_not_reached();
	}
	} else {
	/* A/UX mode */
	switch (irq) {
	case GLUE_IRQ_IN_VIA1:
	irq = 5;
	break;

	case GLUE_IRQ_IN_VIA2:
	irq = 1;
	break;

	case GLUE_IRQ_IN_SONIC:
	irq = 2;
	break;

	case GLUE_IRQ_IN_ESCC:
	irq = 3;
	break;

	case GLUE_IRQ_IN_NMI:
	irq = 6;
	break;

	default:
	g_assert_not_reached();
	}
	}

	if (level) {
	s->ipr \|= 1 << irq;
	} else {
	s->ipr &= ~(1 << irq);
	}

	for (i = 7; i >= 0; i--) {
	if ((s->ipr >> i) & 1) {
	m68k_set_irq_level(s->cpu, i + 1, i + 25);
	return;
	}
	}
	m68k_set_irq_level(s->cpu, 0, 0);
	}

	static void glue_auxmode_set_irq(void *opaque, int irq, int level)
	{
	GLUEState *s = GLUE(opaque);

	s->auxmode = level;
	}

	static void glue_nmi(NMIState n, int cpu_index, Error *errp)
	{
	GLUEState *s = GLUE(n);

	/* Hold NMI active for 100ms */
	GLUE_set_irq(s, GLUE_IRQ_IN_NMI, 1);
	timer_mod(s->nmi_release, qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL) + 100);
	}

	static void glue_nmi_release(void *opaque)
	{
	GLUEState *s = GLUE(opaque);

	GLUE_set_irq(s, GLUE_IRQ_IN_NMI, 0);
	}

	static void glue_reset(DeviceState *dev)
	{
	GLUEState *s = GLUE(dev);

	s->ipr = 0;
	s->auxmode = 0;

	timer_del(s->nmi_release);
	}

	static const VMStateDescription vmstate_glue = {
	.name = "q800-glue",
	.version_id = 0,
	.minimum_version_id = 0,
	.fields = (VMStateField[]) {
	VMSTATE_UINT8(ipr, GLUEState),
	VMSTATE_UINT8(auxmode, GLUEState),
	VMSTATE_TIMER_PTR(nmi_release, GLUEState),
	VMSTATE_END_OF_LIST(),
	},
	};

	/*
	* If the m68k CPU implemented its inbound irq lines as GPIO lines
	* rather than via the m68k_set_irq_level() function we would not need
	* this cpu link property and could instead provide outbound IRQ lines
	* that the board could wire up to the CPU.
	*/
	static Property glue_properties[] = {
	DEFINE_PROP_LINK("cpu", GLUEState, cpu, TYPE_M68K_CPU, M68kCPU *),
	DEFINE_PROP_END_OF_LIST(),
	};

	static void glue_finalize(Object *obj)
	{
	GLUEState *s = GLUE(obj);

	timer_free(s->nmi_release);
	}

	static void glue_init(Object *obj)
	{
	DeviceState *dev = DEVICE(obj);
	GLUEState *s = GLUE(dev);

	qdev_init_gpio_in(dev, GLUE_set_irq, 8);
	qdev_init_gpio_in_named(dev, glue_auxmode_set_irq, "auxmode", 1);

	qdev_init_gpio_out(dev, s->irqs, 1);

	/* NMI release timer */
	s->nmi_release = timer_new_ms(QEMU_CLOCK_VIRTUAL, glue_nmi_release, s);
	}

	static void glue_class_init(ObjectClass klass, void data)
	{
	DeviceClass *dc = DEVICE_CLASS(klass);
	NMIClass *nc = NMI_CLASS(klass);

	dc->vmsd = &vmstate_glue;
	dc->reset = glue_reset;
	device_class_set_props(dc, glue_properties);
	nc->nmi_monitor_handler = glue_nmi;
	}

	static const TypeInfo glue_info_types[] = {
	{
	.name = TYPE_GLUE,
	.parent = TYPE_SYS_BUS_DEVICE,
	.instance_size = sizeof(GLUEState),
	.instance_init = glue_init,
	.instance_finalize = glue_finalize,
	.class_init = glue_class_init,
	.interfaces = (InterfaceInfo[]) {
	{ TYPE_NMI },
	{ }
	},
	},
	};

	DEFINE_TYPES(glue_info_types)