/* The CPM2 internal interrupt controller. It is usually
* the only interrupt controller.
* There are two 32-bit registers (high/low) for up to 64
* possible interrupts.
*
* Now, the fun starts.....Interrupt Numbers DO NOT MAP
* in a simple arithmetic fashion to mask or pending registers.
* That is, interrupt 4 does not map to bit position 4.
* We create two tables, indexed by vector number, to indicate
* which register to use and which bit in the register to use.
*/
#include <linux/stddef.h>
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/signal.h>
#include <linux/irq.h>
#include <asm/immap_cpm2.h>
#include <asm/mpc8260.h>
#include "cpm2_pic.h"
static u_char irq_to_siureg[] = {
1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0
};
/* bit numbers do not match the docs, these are precomputed so the bit for
* a given irq is (1 << irq_to_siubit[irq]) */
static u_char irq_to_siubit[] = {
0, 15, 14, 13, 12, 11, 10, 9,
8, 7, 6, 5, 4, 3, 2, 1,
2, 1, 0, 14, 13, 12, 11, 10,
9, 8, 7, 6, 5, 4, 3, 0,
31, 30, 29, 28, 27, 26, 25, 24,
23, 22, 21, 20, 19, 18, 17, 16,
16, 17, 18, 19, 20, 21, 22, 23,
24, 25, 26, 27, 28, 29, 30, 31,
};
static void cpm2_mask_irq(unsigned int irq_nr)
{
int bit, word;
volatile uint *simr;
irq_nr -= CPM_IRQ_OFFSET;
bit = irq_to_siubit[irq_nr];
word = irq_to_siureg[irq_nr];
simr = &(cpm2_immr->im_intctl.ic_simrh);
ppc_cached_irq_mask[word] &= ~(1 << bit);
simr[word] = ppc_cached_irq_mask[word];
}
static void cpm2_unmask_irq(unsigned int irq_nr)
{
int bit, word;
volatile uint *simr;
irq_nr -= CPM_IRQ_OFFSET;
bit = irq_to_siubit[irq_nr];
word = irq_to_siureg[irq_nr];
simr = &(cpm2_immr->im_intctl.ic_simrh);
ppc_cached_irq_mask[word] |= 1 << bit;
simr[word] = ppc_cached_irq_mask[word];
}
static void cpm2_mask_and_ack(unsigned int irq_nr)
{
int bit, word;
volatile uint *simr, *sipnr;
irq_nr -= CPM_IRQ_OFFSET;
bit = irq_to_siubit[irq_nr];
word = irq_to_siureg[irq_nr];
simr = &(cpm2_immr->im_intctl.ic_simrh);
sipnr = &(cpm2_immr->im_intctl.ic_sipnrh);
ppc_cached_irq_mask[word] &= ~(1 << bit);
simr[word] = ppc_cached_irq_mask[word];
sipnr[word] = 1 << bit;
}
static void cpm2_end_irq(unsigned int irq_nr)
{
int bit, word;
volatile uint *simr;
if (!(irq_desc[irq_nr].status & (IRQ_DISABLED|IRQ_INPROGRESS))
&& irq_desc[irq_nr].action) {
irq_nr -= CPM_IRQ_OFFSET;
bit = irq_to_siubit[irq_nr];
word = irq_to_siureg[irq_nr];
simr = &(cpm2_immr->im_intctl.ic_simrh);
ppc_cached_irq_mask[word] |= 1 << bit;
simr[word] = ppc_cached_irq_mask[word];
/*
* Work around large numbers of spurious IRQs on PowerPC 82xx
* systems.
*/
mb();
}
}
static struct hw_interrupt_type cpm2_pic = {
.typename = " CPM2 SIU ",
.enable = cpm2_unmask_irq,
.disable = cpm2_mask_irq,
.ack = cpm2_mask_and_ack,
.end = cpm2_end_irq,
};
int cpm2_get_irq(void)
{
int irq;
unsigned long bits;
/* For CPM2, read the SIVEC register and shift the bits down
* to get the irq number. */
bits = cpm2_immr->im_intctl.ic_sivec;
irq = bits >> 26;
if (irq == 0)
return(-1);
return irq+CPM_IRQ_OFFSET;
}
void cpm2_init_IRQ(void)
{
int i;
/* Clear the CPM IRQ controller, in case it has any bits set
* from the bootloader
*/
/* Mask out everything */
cpm2_immr->im_intctl.ic_simrh = 0x00000000;
cpm2_immr->im_intctl.ic_simrl = 0x00000000;
wmb();
/* Ack everything */
cpm2_immr->im_intctl.ic_sipnrh = 0xffffffff;
cpm2_immr->im_intctl.ic_sipnrl = 0xffffffff;
wmb();
/* Dummy read of the vector */
i = cpm2_immr->im_intctl.ic_sivec;
rmb();
/* Initialize the default interrupt mapping priorities,
* in case the boot rom changed something on us.
*/
cpm2_immr->im_intctl.ic_sicr = 0;
cpm2_immr->im_intctl.ic_scprrh = 0x05309770;
cpm2_immr->im_intctl.ic_scprrl = 0x05309770;
/* Enable chaining to OpenPIC, and make everything level
*/
for (i = 0; i < NR_CPM_INTS; i++) {
irq_desc[i+CPM_IRQ_OFFSET].chip = &cpm2_pic;
irq_desc[i+CPM_IRQ_OFFSET].status |= IRQ_LEVEL;
}
}
