qemu-e2k/hw/pl190.c

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/*
* Arm PrimeCell PL190 Vector Interrupt Controller
*
* Copyright (c) 2006 CodeSourcery.
* Written by Paul Brook
*
* This code is licenced under the GPL.
*/
#include "hw.h"
#include "primecell.h"
/* The number of virtual priority levels. 16 user vectors plus the
unvectored IRQ. Chained interrupts would require an additional level
if implemented. */
#define PL190_NUM_PRIO 17
typedef struct {
uint32_t level;
uint32_t soft_level;
uint32_t irq_enable;
uint32_t fiq_select;
uint32_t default_addr;
uint8_t vect_control[16];
uint32_t vect_addr[PL190_NUM_PRIO];
/* Mask containing interrupts with higher priority than this one. */
uint32_t prio_mask[PL190_NUM_PRIO + 1];
int protected;
/* Current priority level. */
int priority;
int prev_prio[PL190_NUM_PRIO];
qemu_irq irq;
qemu_irq fiq;
} pl190_state;
static const unsigned char pl190_id[] =
{ 0x90, 0x11, 0x04, 0x00, 0x0D, 0xf0, 0x05, 0xb1 };
static inline uint32_t pl190_irq_level(pl190_state *s)
{
return (s->level | s->soft_level) & s->irq_enable & ~s->fiq_select;
}
/* Update interrupts. */
static void pl190_update(pl190_state *s)
{
uint32_t level = pl190_irq_level(s);
int set;
set = (level & s->prio_mask[s->priority]) != 0;
qemu_set_irq(s->irq, set);
set = ((s->level | s->soft_level) & s->fiq_select) != 0;
qemu_set_irq(s->fiq, set);
}
static void pl190_set_irq(void *opaque, int irq, int level)
{
pl190_state *s = (pl190_state *)opaque;
if (level)
s->level |= 1u << irq;
else
s->level &= ~(1u << irq);
pl190_update(s);
}
static void pl190_update_vectors(pl190_state *s)
{
uint32_t mask;
int i;
int n;
mask = 0;
for (i = 0; i < 16; i++)
{
s->prio_mask[i] = mask;
if (s->vect_control[i] & 0x20)
{
n = s->vect_control[i] & 0x1f;
mask |= 1 << n;
}
}
s->prio_mask[16] = mask;
pl190_update(s);
}
static uint32_t pl190_read(void *opaque, target_phys_addr_t offset)
{
pl190_state *s = (pl190_state *)opaque;
int i;
if (offset >= 0xfe0 && offset < 0x1000) {
return pl190_id[(offset - 0xfe0) >> 2];
}
if (offset >= 0x100 && offset < 0x140) {
return s->vect_addr[(offset - 0x100) >> 2];
}
if (offset >= 0x200 && offset < 0x240) {
return s->vect_control[(offset - 0x200) >> 2];
}
switch (offset >> 2) {
case 0: /* IRQSTATUS */
return pl190_irq_level(s);
case 1: /* FIQSATUS */
return (s->level | s->soft_level) & s->fiq_select;
case 2: /* RAWINTR */
return s->level | s->soft_level;
case 3: /* INTSELECT */
return s->fiq_select;
case 4: /* INTENABLE */
return s->irq_enable;
case 6: /* SOFTINT */
return s->soft_level;
case 8: /* PROTECTION */
return s->protected;
case 12: /* VECTADDR */
/* Read vector address at the start of an ISR. Increases the
current priority level to that of the current interrupt. */
for (i = 0; i < s->priority; i++)
{
if ((s->level | s->soft_level) & s->prio_mask[i])
break;
}
/* Reading this value with no pending interrupts is undefined.
We return the default address. */
if (i == PL190_NUM_PRIO)
return s->vect_addr[16];
if (i < s->priority)
{
s->prev_prio[i] = s->priority;
s->priority = i;
pl190_update(s);
}
return s->vect_addr[s->priority];
case 13: /* DEFVECTADDR */
return s->vect_addr[16];
default:
hw_error("pl190_read: Bad offset %x\n", (int)offset);
return 0;
}
}
static void pl190_write(void *opaque, target_phys_addr_t offset, uint32_t val)
{
pl190_state *s = (pl190_state *)opaque;
if (offset >= 0x100 && offset < 0x140) {
s->vect_addr[(offset - 0x100) >> 2] = val;
pl190_update_vectors(s);
return;
}
if (offset >= 0x200 && offset < 0x240) {
s->vect_control[(offset - 0x200) >> 2] = val;
pl190_update_vectors(s);
return;
}
switch (offset >> 2) {
case 0: /* SELECT */
/* This is a readonly register, but linux tries to write to it
anyway. Ignore the write. */
break;
case 3: /* INTSELECT */
s->fiq_select = val;
break;
case 4: /* INTENABLE */
s->irq_enable |= val;
break;
case 5: /* INTENCLEAR */
s->irq_enable &= ~val;
break;
case 6: /* SOFTINT */
s->soft_level |= val;
break;
case 7: /* SOFTINTCLEAR */
s->soft_level &= ~val;
break;
case 8: /* PROTECTION */
/* TODO: Protection (supervisor only access) is not implemented. */
s->protected = val & 1;
break;
case 12: /* VECTADDR */
/* Restore the previous priority level. The value written is
ignored. */
if (s->priority < PL190_NUM_PRIO)
s->priority = s->prev_prio[s->priority];
break;
case 13: /* DEFVECTADDR */
s->default_addr = val;
break;
case 0xc0: /* ITCR */
if (val) {
hw_error("pl190: Test mode not implemented\n");
}
break;
default:
hw_error("pl190_write: Bad offset %x\n", (int)offset);
return;
}
pl190_update(s);
}
static CPUReadMemoryFunc *pl190_readfn[] = {
pl190_read,
pl190_read,
pl190_read
};
static CPUWriteMemoryFunc *pl190_writefn[] = {
pl190_write,
pl190_write,
pl190_write
};
static void pl190_reset(pl190_state *s)
{
int i;
for (i = 0; i < 16; i++)
{
s->vect_addr[i] = 0;
s->vect_control[i] = 0;
}
s->vect_addr[16] = 0;
s->prio_mask[17] = 0xffffffff;
s->priority = PL190_NUM_PRIO;
pl190_update_vectors(s);
}
qemu_irq *pl190_init(uint32_t base, qemu_irq irq, qemu_irq fiq)
{
pl190_state *s;
qemu_irq *qi;
int iomemtype;
s = (pl190_state *)qemu_mallocz(sizeof(pl190_state));
iomemtype = cpu_register_io_memory(0, pl190_readfn,
pl190_writefn, s);
cpu_register_physical_memory(base, 0x00001000, iomemtype);
qi = qemu_allocate_irqs(pl190_set_irq, s, 32);
s->irq = irq;
s->fiq = fiq;
pl190_reset(s);
/* ??? Save/restore. */
return qi;
}