kernel_optimize_test/arch/microblaze/kernel/intc.c
steve@digidescorp.com 33d9ff5985 microblaze: Fix level interrupt ACKing
Level interrupts need to be ack'd in the unmask handler, as in powerpc.
Among other issues, this bug causes the system clock to appear to run at
double-speed.

Signed-off-by: Steven J. Magnani <steve@digidescorp.com>
Signed-off-by: Michal Simek <monstr@monstr.eu>
2009-12-14 08:45:06 +01:00

183 lines
4.6 KiB
C

/*
* Copyright (C) 2007-2009 Michal Simek <monstr@monstr.eu>
* Copyright (C) 2007-2009 PetaLogix
* Copyright (C) 2006 Atmark Techno, Inc.
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/init.h>
#include <linux/irq.h>
#include <asm/page.h>
#include <linux/io.h>
#include <linux/bug.h>
#include <asm/prom.h>
#include <asm/irq.h>
#ifdef CONFIG_SELFMOD_INTC
#include <asm/selfmod.h>
#define INTC_BASE BARRIER_BASE_ADDR
#else
static unsigned int intc_baseaddr;
#define INTC_BASE intc_baseaddr
#endif
unsigned int nr_irq;
/* No one else should require these constants, so define them locally here. */
#define ISR 0x00 /* Interrupt Status Register */
#define IPR 0x04 /* Interrupt Pending Register */
#define IER 0x08 /* Interrupt Enable Register */
#define IAR 0x0c /* Interrupt Acknowledge Register */
#define SIE 0x10 /* Set Interrupt Enable bits */
#define CIE 0x14 /* Clear Interrupt Enable bits */
#define IVR 0x18 /* Interrupt Vector Register */
#define MER 0x1c /* Master Enable Register */
#define MER_ME (1<<0)
#define MER_HIE (1<<1)
static void intc_enable_or_unmask(unsigned int irq)
{
unsigned long mask = 1 << irq;
pr_debug("enable_or_unmask: %d\n", irq);
out_be32(INTC_BASE + SIE, mask);
/* ack level irqs because they can't be acked during
* ack function since the handle_level_irq function
* acks the irq before calling the interrupt handler
*/
if (irq_desc[irq].status & IRQ_LEVEL)
out_be32(INTC_BASE + IAR, mask);
}
static void intc_disable_or_mask(unsigned int irq)
{
pr_debug("disable: %d\n", irq);
out_be32(INTC_BASE + CIE, 1 << irq);
}
static void intc_ack(unsigned int irq)
{
pr_debug("ack: %d\n", irq);
out_be32(INTC_BASE + IAR, 1 << irq);
}
static void intc_mask_ack(unsigned int irq)
{
unsigned long mask = 1 << irq;
pr_debug("disable_and_ack: %d\n", irq);
out_be32(INTC_BASE + CIE, mask);
out_be32(INTC_BASE + IAR, mask);
}
static void intc_end(unsigned int irq)
{
unsigned long mask = 1 << irq;
pr_debug("end: %d\n", irq);
if (!(irq_desc[irq].status & (IRQ_DISABLED | IRQ_INPROGRESS))) {
out_be32(INTC_BASE + SIE, mask);
/* ack level sensitive intr */
if (irq_desc[irq].status & IRQ_LEVEL)
out_be32(INTC_BASE + IAR, mask);
}
}
static struct irq_chip intc_dev = {
.name = "Xilinx INTC",
.unmask = intc_enable_or_unmask,
.mask = intc_disable_or_mask,
.ack = intc_ack,
.mask_ack = intc_mask_ack,
.end = intc_end,
};
unsigned int get_irq(struct pt_regs *regs)
{
int irq;
/*
* NOTE: This function is the one that needs to be improved in
* order to handle multiple interrupt controllers. It currently
* is hardcoded to check for interrupts only on the first INTC.
*/
irq = in_be32(INTC_BASE + IVR);
pr_debug("get_irq: %d\n", irq);
return irq;
}
void __init init_IRQ(void)
{
u32 i, j, intr_type;
struct device_node *intc = NULL;
#ifdef CONFIG_SELFMOD_INTC
unsigned int intc_baseaddr = 0;
static int arr_func[] = {
(int)&get_irq,
(int)&intc_enable_or_unmask,
(int)&intc_disable_or_mask,
(int)&intc_mask_ack,
(int)&intc_ack,
(int)&intc_end,
0
};
#endif
static char *intc_list[] = {
"xlnx,xps-intc-1.00.a",
"xlnx,opb-intc-1.00.c",
"xlnx,opb-intc-1.00.b",
"xlnx,opb-intc-1.00.a",
NULL
};
for (j = 0; intc_list[j] != NULL; j++) {
intc = of_find_compatible_node(NULL, NULL, intc_list[j]);
if (intc)
break;
}
BUG_ON(!intc);
intc_baseaddr = *(int *) of_get_property(intc, "reg", NULL);
intc_baseaddr = (unsigned long) ioremap(intc_baseaddr, PAGE_SIZE);
nr_irq = *(int *) of_get_property(intc, "xlnx,num-intr-inputs", NULL);
intr_type =
*(int *) of_get_property(intc, "xlnx,kind-of-intr", NULL);
if (intr_type >= (1 << (nr_irq + 1)))
printk(KERN_INFO " ERROR: Mismatch in kind-of-intr param\n");
#ifdef CONFIG_SELFMOD_INTC
selfmod_function((int *) arr_func, intc_baseaddr);
#endif
printk(KERN_INFO "%s #0 at 0x%08x, num_irq=%d, edge=0x%x\n",
intc_list[j], intc_baseaddr, nr_irq, intr_type);
/*
* Disable all external interrupts until they are
* explicity requested.
*/
out_be32(intc_baseaddr + IER, 0);
/* Acknowledge any pending interrupts just in case. */
out_be32(intc_baseaddr + IAR, 0xffffffff);
/* Turn on the Master Enable. */
out_be32(intc_baseaddr + MER, MER_HIE | MER_ME);
for (i = 0; i < nr_irq; ++i) {
if (intr_type & (0x00000001 << i)) {
set_irq_chip_and_handler_name(i, &intc_dev,
handle_edge_irq, intc_dev.name);
irq_desc[i].status &= ~IRQ_LEVEL;
} else {
set_irq_chip_and_handler_name(i, &intc_dev,
handle_level_irq, intc_dev.name);
irq_desc[i].status |= IRQ_LEVEL;
}
}
}