linux/arch/mips/lantiq/irq.c
John Crispin 171bb2f19e MIPS: Lantiq: Add initial support for Lantiq SoCs
Add initial support for Mips based SoCs made by Lantiq. This series will add
support for the XWAY family.

The series allows booting a minimal system using a initramfs or NOR. Missing
drivers and support for Amazon and GPON family will be provided in a later
series.

[Ralf: Remove some cargo cult programming and fixed formatting.]

Signed-off-by: John Crispin <blogic@openwrt.org>
Signed-off-by: Ralph Hempel <ralph.hempel@lantiq.com>
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2252/
Patchwork: https://patchwork.linux-mips.org/patch/2371/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2011-05-19 09:55:41 +01:00

327 lines
8.2 KiB
C

/*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published
* by the Free Software Foundation.
*
* Copyright (C) 2010 John Crispin <blogic@openwrt.org>
* Copyright (C) 2010 Thomas Langer <thomas.langer@lantiq.com>
*/
#include <linux/interrupt.h>
#include <linux/ioport.h>
#include <asm/bootinfo.h>
#include <asm/irq_cpu.h>
#include <lantiq_soc.h>
#include <irq.h>
/* register definitions */
#define LTQ_ICU_IM0_ISR 0x0000
#define LTQ_ICU_IM0_IER 0x0008
#define LTQ_ICU_IM0_IOSR 0x0010
#define LTQ_ICU_IM0_IRSR 0x0018
#define LTQ_ICU_IM0_IMR 0x0020
#define LTQ_ICU_IM1_ISR 0x0028
#define LTQ_ICU_OFFSET (LTQ_ICU_IM1_ISR - LTQ_ICU_IM0_ISR)
#define LTQ_EIU_EXIN_C 0x0000
#define LTQ_EIU_EXIN_INIC 0x0004
#define LTQ_EIU_EXIN_INEN 0x000C
/* irq numbers used by the external interrupt unit (EIU) */
#define LTQ_EIU_IR0 (INT_NUM_IM4_IRL0 + 30)
#define LTQ_EIU_IR1 (INT_NUM_IM3_IRL0 + 31)
#define LTQ_EIU_IR2 (INT_NUM_IM1_IRL0 + 26)
#define LTQ_EIU_IR3 INT_NUM_IM1_IRL0
#define LTQ_EIU_IR4 (INT_NUM_IM1_IRL0 + 1)
#define LTQ_EIU_IR5 (INT_NUM_IM1_IRL0 + 2)
#define LTQ_EIU_IR6 (INT_NUM_IM2_IRL0 + 30)
#define MAX_EIU 6
/* irqs generated by device attached to the EBU need to be acked in
* a special manner
*/
#define LTQ_ICU_EBU_IRQ 22
#define ltq_icu_w32(x, y) ltq_w32((x), ltq_icu_membase + (y))
#define ltq_icu_r32(x) ltq_r32(ltq_icu_membase + (x))
#define ltq_eiu_w32(x, y) ltq_w32((x), ltq_eiu_membase + (y))
#define ltq_eiu_r32(x) ltq_r32(ltq_eiu_membase + (x))
static unsigned short ltq_eiu_irq[MAX_EIU] = {
LTQ_EIU_IR0,
LTQ_EIU_IR1,
LTQ_EIU_IR2,
LTQ_EIU_IR3,
LTQ_EIU_IR4,
LTQ_EIU_IR5,
};
static struct resource ltq_icu_resource = {
.name = "icu",
.start = LTQ_ICU_BASE_ADDR,
.end = LTQ_ICU_BASE_ADDR + LTQ_ICU_SIZE - 1,
.flags = IORESOURCE_MEM,
};
static struct resource ltq_eiu_resource = {
.name = "eiu",
.start = LTQ_EIU_BASE_ADDR,
.end = LTQ_EIU_BASE_ADDR + LTQ_ICU_SIZE - 1,
.flags = IORESOURCE_MEM,
};
static void __iomem *ltq_icu_membase;
static void __iomem *ltq_eiu_membase;
void ltq_disable_irq(struct irq_data *d)
{
u32 ier = LTQ_ICU_IM0_IER;
int irq_nr = d->irq - INT_NUM_IRQ0;
ier += LTQ_ICU_OFFSET * (irq_nr / INT_NUM_IM_OFFSET);
irq_nr %= INT_NUM_IM_OFFSET;
ltq_icu_w32(ltq_icu_r32(ier) & ~(1 << irq_nr), ier);
}
void ltq_mask_and_ack_irq(struct irq_data *d)
{
u32 ier = LTQ_ICU_IM0_IER;
u32 isr = LTQ_ICU_IM0_ISR;
int irq_nr = d->irq - INT_NUM_IRQ0;
ier += LTQ_ICU_OFFSET * (irq_nr / INT_NUM_IM_OFFSET);
isr += LTQ_ICU_OFFSET * (irq_nr / INT_NUM_IM_OFFSET);
irq_nr %= INT_NUM_IM_OFFSET;
ltq_icu_w32(ltq_icu_r32(ier) & ~(1 << irq_nr), ier);
ltq_icu_w32((1 << irq_nr), isr);
}
static void ltq_ack_irq(struct irq_data *d)
{
u32 isr = LTQ_ICU_IM0_ISR;
int irq_nr = d->irq - INT_NUM_IRQ0;
isr += LTQ_ICU_OFFSET * (irq_nr / INT_NUM_IM_OFFSET);
irq_nr %= INT_NUM_IM_OFFSET;
ltq_icu_w32((1 << irq_nr), isr);
}
void ltq_enable_irq(struct irq_data *d)
{
u32 ier = LTQ_ICU_IM0_IER;
int irq_nr = d->irq - INT_NUM_IRQ0;
ier += LTQ_ICU_OFFSET * (irq_nr / INT_NUM_IM_OFFSET);
irq_nr %= INT_NUM_IM_OFFSET;
ltq_icu_w32(ltq_icu_r32(ier) | (1 << irq_nr), ier);
}
static unsigned int ltq_startup_eiu_irq(struct irq_data *d)
{
int i;
int irq_nr = d->irq - INT_NUM_IRQ0;
ltq_enable_irq(d);
for (i = 0; i < MAX_EIU; i++) {
if (irq_nr == ltq_eiu_irq[i]) {
/* low level - we should really handle set_type */
ltq_eiu_w32(ltq_eiu_r32(LTQ_EIU_EXIN_C) |
(0x6 << (i * 4)), LTQ_EIU_EXIN_C);
/* clear all pending */
ltq_eiu_w32(ltq_eiu_r32(LTQ_EIU_EXIN_INIC) & ~(1 << i),
LTQ_EIU_EXIN_INIC);
/* enable */
ltq_eiu_w32(ltq_eiu_r32(LTQ_EIU_EXIN_INEN) | (1 << i),
LTQ_EIU_EXIN_INEN);
break;
}
}
return 0;
}
static void ltq_shutdown_eiu_irq(struct irq_data *d)
{
int i;
int irq_nr = d->irq - INT_NUM_IRQ0;
ltq_disable_irq(d);
for (i = 0; i < MAX_EIU; i++) {
if (irq_nr == ltq_eiu_irq[i]) {
/* disable */
ltq_eiu_w32(ltq_eiu_r32(LTQ_EIU_EXIN_INEN) & ~(1 << i),
LTQ_EIU_EXIN_INEN);
break;
}
}
}
static struct irq_chip ltq_irq_type = {
"icu",
.irq_enable = ltq_enable_irq,
.irq_disable = ltq_disable_irq,
.irq_unmask = ltq_enable_irq,
.irq_ack = ltq_ack_irq,
.irq_mask = ltq_disable_irq,
.irq_mask_ack = ltq_mask_and_ack_irq,
};
static struct irq_chip ltq_eiu_type = {
"eiu",
.irq_startup = ltq_startup_eiu_irq,
.irq_shutdown = ltq_shutdown_eiu_irq,
.irq_enable = ltq_enable_irq,
.irq_disable = ltq_disable_irq,
.irq_unmask = ltq_enable_irq,
.irq_ack = ltq_ack_irq,
.irq_mask = ltq_disable_irq,
.irq_mask_ack = ltq_mask_and_ack_irq,
};
static void ltq_hw_irqdispatch(int module)
{
u32 irq;
irq = ltq_icu_r32(LTQ_ICU_IM0_IOSR + (module * LTQ_ICU_OFFSET));
if (irq == 0)
return;
/* silicon bug causes only the msb set to 1 to be valid. all
* other bits might be bogus
*/
irq = __fls(irq);
do_IRQ((int)irq + INT_NUM_IM0_IRL0 + (INT_NUM_IM_OFFSET * module));
/* if this is a EBU irq, we need to ack it or get a deadlock */
if ((irq == LTQ_ICU_EBU_IRQ) && (module == 0))
ltq_ebu_w32(ltq_ebu_r32(LTQ_EBU_PCC_ISTAT) | 0x10,
LTQ_EBU_PCC_ISTAT);
}
#define DEFINE_HWx_IRQDISPATCH(x) \
static void ltq_hw ## x ## _irqdispatch(void) \
{ \
ltq_hw_irqdispatch(x); \
}
DEFINE_HWx_IRQDISPATCH(0)
DEFINE_HWx_IRQDISPATCH(1)
DEFINE_HWx_IRQDISPATCH(2)
DEFINE_HWx_IRQDISPATCH(3)
DEFINE_HWx_IRQDISPATCH(4)
static void ltq_hw5_irqdispatch(void)
{
do_IRQ(MIPS_CPU_TIMER_IRQ);
}
asmlinkage void plat_irq_dispatch(void)
{
unsigned int pending = read_c0_status() & read_c0_cause() & ST0_IM;
unsigned int i;
if (pending & CAUSEF_IP7) {
do_IRQ(MIPS_CPU_TIMER_IRQ);
goto out;
} else {
for (i = 0; i < 5; i++) {
if (pending & (CAUSEF_IP2 << i)) {
ltq_hw_irqdispatch(i);
goto out;
}
}
}
pr_alert("Spurious IRQ: CAUSE=0x%08x\n", read_c0_status());
out:
return;
}
static struct irqaction cascade = {
.handler = no_action,
.flags = IRQF_DISABLED,
.name = "cascade",
};
void __init arch_init_irq(void)
{
int i;
if (insert_resource(&iomem_resource, &ltq_icu_resource) < 0)
panic("Failed to insert icu memory\n");
if (request_mem_region(ltq_icu_resource.start,
resource_size(&ltq_icu_resource), "icu") < 0)
panic("Failed to request icu memory\n");
ltq_icu_membase = ioremap_nocache(ltq_icu_resource.start,
resource_size(&ltq_icu_resource));
if (!ltq_icu_membase)
panic("Failed to remap icu memory\n");
if (insert_resource(&iomem_resource, &ltq_eiu_resource) < 0)
panic("Failed to insert eiu memory\n");
if (request_mem_region(ltq_eiu_resource.start,
resource_size(&ltq_eiu_resource), "eiu") < 0)
panic("Failed to request eiu memory\n");
ltq_eiu_membase = ioremap_nocache(ltq_eiu_resource.start,
resource_size(&ltq_eiu_resource));
if (!ltq_eiu_membase)
panic("Failed to remap eiu memory\n");
/* make sure all irqs are turned off by default */
for (i = 0; i < 5; i++)
ltq_icu_w32(0, LTQ_ICU_IM0_IER + (i * LTQ_ICU_OFFSET));
/* clear all possibly pending interrupts */
ltq_icu_w32(~0, LTQ_ICU_IM0_ISR + (i * LTQ_ICU_OFFSET));
mips_cpu_irq_init();
for (i = 2; i <= 6; i++)
setup_irq(i, &cascade);
if (cpu_has_vint) {
pr_info("Setting up vectored interrupts\n");
set_vi_handler(2, ltq_hw0_irqdispatch);
set_vi_handler(3, ltq_hw1_irqdispatch);
set_vi_handler(4, ltq_hw2_irqdispatch);
set_vi_handler(5, ltq_hw3_irqdispatch);
set_vi_handler(6, ltq_hw4_irqdispatch);
set_vi_handler(7, ltq_hw5_irqdispatch);
}
for (i = INT_NUM_IRQ0;
i <= (INT_NUM_IRQ0 + (5 * INT_NUM_IM_OFFSET)); i++)
if ((i == LTQ_EIU_IR0) || (i == LTQ_EIU_IR1) ||
(i == LTQ_EIU_IR2))
irq_set_chip_and_handler(i, &ltq_eiu_type,
handle_level_irq);
/* EIU3-5 only exist on ar9 and vr9 */
else if (((i == LTQ_EIU_IR3) || (i == LTQ_EIU_IR4) ||
(i == LTQ_EIU_IR5)) && (ltq_is_ar9() || ltq_is_vr9()))
irq_set_chip_and_handler(i, &ltq_eiu_type,
handle_level_irq);
else
irq_set_chip_and_handler(i, &ltq_irq_type,
handle_level_irq);
#if !defined(CONFIG_MIPS_MT_SMP) && !defined(CONFIG_MIPS_MT_SMTC)
set_c0_status(IE_IRQ0 | IE_IRQ1 | IE_IRQ2 |
IE_IRQ3 | IE_IRQ4 | IE_IRQ5);
#else
set_c0_status(IE_SW0 | IE_SW1 | IE_IRQ0 | IE_IRQ1 |
IE_IRQ2 | IE_IRQ3 | IE_IRQ4 | IE_IRQ5);
#endif
}
unsigned int __cpuinit get_c0_compare_int(void)
{
return CP0_LEGACY_COMPARE_IRQ;
}