kernel-fxtec-pro1x/arch/mips/cavium-octeon/octeon-irq.c
David Daney b6b74d5490 MIPS: Octeon: Use write_{un,}lock_irq{restore,save} to set irq affinity
Since the locks are used from interrupt context we need the
irqsave/irqrestore versions of the locking functions.

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2009-11-02 12:00:07 +01:00

564 lines
16 KiB
C

/*
* 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.
*
* Copyright (C) 2004-2008 Cavium Networks
*/
#include <linux/irq.h>
#include <linux/interrupt.h>
#include <linux/smp.h>
#include <asm/octeon/octeon.h>
#include <asm/octeon/cvmx-pexp-defs.h>
#include <asm/octeon/cvmx-npi-defs.h>
DEFINE_RWLOCK(octeon_irq_ciu0_rwlock);
DEFINE_RWLOCK(octeon_irq_ciu1_rwlock);
DEFINE_SPINLOCK(octeon_irq_msi_lock);
static void octeon_irq_core_ack(unsigned int irq)
{
unsigned int bit = irq - OCTEON_IRQ_SW0;
/*
* We don't need to disable IRQs to make these atomic since
* they are already disabled earlier in the low level
* interrupt code.
*/
clear_c0_status(0x100 << bit);
/* The two user interrupts must be cleared manually. */
if (bit < 2)
clear_c0_cause(0x100 << bit);
}
static void octeon_irq_core_eoi(unsigned int irq)
{
struct irq_desc *desc = irq_desc + irq;
unsigned int bit = irq - OCTEON_IRQ_SW0;
/*
* If an IRQ is being processed while we are disabling it the
* handler will attempt to unmask the interrupt after it has
* been disabled.
*/
if (desc->status & IRQ_DISABLED)
return;
/* There is a race here. We should fix it. */
/*
* We don't need to disable IRQs to make these atomic since
* they are already disabled earlier in the low level
* interrupt code.
*/
set_c0_status(0x100 << bit);
}
static void octeon_irq_core_enable(unsigned int irq)
{
unsigned long flags;
unsigned int bit = irq - OCTEON_IRQ_SW0;
/*
* We need to disable interrupts to make sure our updates are
* atomic.
*/
local_irq_save(flags);
set_c0_status(0x100 << bit);
local_irq_restore(flags);
}
static void octeon_irq_core_disable_local(unsigned int irq)
{
unsigned long flags;
unsigned int bit = irq - OCTEON_IRQ_SW0;
/*
* We need to disable interrupts to make sure our updates are
* atomic.
*/
local_irq_save(flags);
clear_c0_status(0x100 << bit);
local_irq_restore(flags);
}
static void octeon_irq_core_disable(unsigned int irq)
{
#ifdef CONFIG_SMP
on_each_cpu((void (*)(void *)) octeon_irq_core_disable_local,
(void *) (long) irq, 1);
#else
octeon_irq_core_disable_local(irq);
#endif
}
static struct irq_chip octeon_irq_chip_core = {
.name = "Core",
.enable = octeon_irq_core_enable,
.disable = octeon_irq_core_disable,
.ack = octeon_irq_core_ack,
.eoi = octeon_irq_core_eoi,
};
static void octeon_irq_ciu0_ack(unsigned int irq)
{
/*
* In order to avoid any locking accessing the CIU, we
* acknowledge CIU interrupts by disabling all of them. This
* way we can use a per core register and avoid any out of
* core locking requirements. This has the side affect that
* CIU interrupts can't be processed recursively.
*
* We don't need to disable IRQs to make these atomic since
* they are already disabled earlier in the low level
* interrupt code.
*/
clear_c0_status(0x100 << 2);
}
static void octeon_irq_ciu0_eoi(unsigned int irq)
{
/*
* Enable all CIU interrupts again. We don't need to disable
* IRQs to make these atomic since they are already disabled
* earlier in the low level interrupt code.
*/
set_c0_status(0x100 << 2);
}
static void octeon_irq_ciu0_enable(unsigned int irq)
{
int coreid = cvmx_get_core_num();
unsigned long flags;
uint64_t en0;
int bit = irq - OCTEON_IRQ_WORKQ0; /* Bit 0-63 of EN0 */
/*
* A read lock is used here to make sure only one core is ever
* updating the CIU enable bits at a time. During an enable
* the cores don't interfere with each other. During a disable
* the write lock stops any enables that might cause a
* problem.
*/
read_lock_irqsave(&octeon_irq_ciu0_rwlock, flags);
en0 = cvmx_read_csr(CVMX_CIU_INTX_EN0(coreid * 2));
en0 |= 1ull << bit;
cvmx_write_csr(CVMX_CIU_INTX_EN0(coreid * 2), en0);
cvmx_read_csr(CVMX_CIU_INTX_EN0(coreid * 2));
read_unlock_irqrestore(&octeon_irq_ciu0_rwlock, flags);
}
static void octeon_irq_ciu0_disable(unsigned int irq)
{
int bit = irq - OCTEON_IRQ_WORKQ0; /* Bit 0-63 of EN0 */
unsigned long flags;
uint64_t en0;
#ifdef CONFIG_SMP
int cpu;
write_lock_irqsave(&octeon_irq_ciu0_rwlock, flags);
for_each_online_cpu(cpu) {
int coreid = cpu_logical_map(cpu);
en0 = cvmx_read_csr(CVMX_CIU_INTX_EN0(coreid * 2));
en0 &= ~(1ull << bit);
cvmx_write_csr(CVMX_CIU_INTX_EN0(coreid * 2), en0);
}
/*
* We need to do a read after the last update to make sure all
* of them are done.
*/
cvmx_read_csr(CVMX_CIU_INTX_EN0(cvmx_get_core_num() * 2));
write_unlock_irqrestore(&octeon_irq_ciu0_rwlock, flags);
#else
int coreid = cvmx_get_core_num();
local_irq_save(flags);
en0 = cvmx_read_csr(CVMX_CIU_INTX_EN0(coreid * 2));
en0 &= ~(1ull << bit);
cvmx_write_csr(CVMX_CIU_INTX_EN0(coreid * 2), en0);
cvmx_read_csr(CVMX_CIU_INTX_EN0(coreid * 2));
local_irq_restore(flags);
#endif
}
#ifdef CONFIG_SMP
static int octeon_irq_ciu0_set_affinity(unsigned int irq, const struct cpumask *dest)
{
int cpu;
unsigned long flags;
int bit = irq - OCTEON_IRQ_WORKQ0; /* Bit 0-63 of EN0 */
write_lock_irqsave(&octeon_irq_ciu0_rwlock, flags);
for_each_online_cpu(cpu) {
int coreid = cpu_logical_map(cpu);
uint64_t en0 =
cvmx_read_csr(CVMX_CIU_INTX_EN0(coreid * 2));
if (cpumask_test_cpu(cpu, dest))
en0 |= 1ull << bit;
else
en0 &= ~(1ull << bit);
cvmx_write_csr(CVMX_CIU_INTX_EN0(coreid * 2), en0);
}
/*
* We need to do a read after the last update to make sure all
* of them are done.
*/
cvmx_read_csr(CVMX_CIU_INTX_EN0(cvmx_get_core_num() * 2));
write_unlock_irqrestore(&octeon_irq_ciu0_rwlock, flags);
return 0;
}
#endif
static struct irq_chip octeon_irq_chip_ciu0 = {
.name = "CIU0",
.enable = octeon_irq_ciu0_enable,
.disable = octeon_irq_ciu0_disable,
.ack = octeon_irq_ciu0_ack,
.eoi = octeon_irq_ciu0_eoi,
#ifdef CONFIG_SMP
.set_affinity = octeon_irq_ciu0_set_affinity,
#endif
};
static void octeon_irq_ciu1_ack(unsigned int irq)
{
/*
* In order to avoid any locking accessing the CIU, we
* acknowledge CIU interrupts by disabling all of them. This
* way we can use a per core register and avoid any out of
* core locking requirements. This has the side affect that
* CIU interrupts can't be processed recursively. We don't
* need to disable IRQs to make these atomic since they are
* already disabled earlier in the low level interrupt code.
*/
clear_c0_status(0x100 << 3);
}
static void octeon_irq_ciu1_eoi(unsigned int irq)
{
/*
* Enable all CIU interrupts again. We don't need to disable
* IRQs to make these atomic since they are already disabled
* earlier in the low level interrupt code.
*/
set_c0_status(0x100 << 3);
}
static void octeon_irq_ciu1_enable(unsigned int irq)
{
int coreid = cvmx_get_core_num();
unsigned long flags;
uint64_t en1;
int bit = irq - OCTEON_IRQ_WDOG0; /* Bit 0-63 of EN1 */
/*
* A read lock is used here to make sure only one core is ever
* updating the CIU enable bits at a time. During an enable
* the cores don't interfere with each other. During a disable
* the write lock stops any enables that might cause a
* problem.
*/
read_lock_irqsave(&octeon_irq_ciu1_rwlock, flags);
en1 = cvmx_read_csr(CVMX_CIU_INTX_EN1(coreid * 2 + 1));
en1 |= 1ull << bit;
cvmx_write_csr(CVMX_CIU_INTX_EN1(coreid * 2 + 1), en1);
cvmx_read_csr(CVMX_CIU_INTX_EN1(coreid * 2 + 1));
read_unlock_irqrestore(&octeon_irq_ciu1_rwlock, flags);
}
static void octeon_irq_ciu1_disable(unsigned int irq)
{
int bit = irq - OCTEON_IRQ_WDOG0; /* Bit 0-63 of EN1 */
unsigned long flags;
uint64_t en1;
#ifdef CONFIG_SMP
int cpu;
write_lock_irqsave(&octeon_irq_ciu1_rwlock, flags);
for_each_online_cpu(cpu) {
int coreid = cpu_logical_map(cpu);
en1 = cvmx_read_csr(CVMX_CIU_INTX_EN1(coreid * 2 + 1));
en1 &= ~(1ull << bit);
cvmx_write_csr(CVMX_CIU_INTX_EN1(coreid * 2 + 1), en1);
}
/*
* We need to do a read after the last update to make sure all
* of them are done.
*/
cvmx_read_csr(CVMX_CIU_INTX_EN1(cvmx_get_core_num() * 2 + 1));
write_unlock_irqrestore(&octeon_irq_ciu1_rwlock, flags);
#else
int coreid = cvmx_get_core_num();
local_irq_save(flags);
en1 = cvmx_read_csr(CVMX_CIU_INTX_EN1(coreid * 2 + 1));
en1 &= ~(1ull << bit);
cvmx_write_csr(CVMX_CIU_INTX_EN1(coreid * 2 + 1), en1);
cvmx_read_csr(CVMX_CIU_INTX_EN1(coreid * 2 + 1));
local_irq_restore(flags);
#endif
}
#ifdef CONFIG_SMP
static int octeon_irq_ciu1_set_affinity(unsigned int irq, const struct cpumask *dest)
{
int cpu;
unsigned long flags;
int bit = irq - OCTEON_IRQ_WDOG0; /* Bit 0-63 of EN1 */
write_lock_irqsave(&octeon_irq_ciu1_rwlock, flags);
for_each_online_cpu(cpu) {
int coreid = cpu_logical_map(cpu);
uint64_t en1 =
cvmx_read_csr(CVMX_CIU_INTX_EN1
(coreid * 2 + 1));
if (cpumask_test_cpu(cpu, dest))
en1 |= 1ull << bit;
else
en1 &= ~(1ull << bit);
cvmx_write_csr(CVMX_CIU_INTX_EN1(coreid * 2 + 1), en1);
}
/*
* We need to do a read after the last update to make sure all
* of them are done.
*/
cvmx_read_csr(CVMX_CIU_INTX_EN1(cvmx_get_core_num() * 2 + 1));
write_unlock_irqrestore(&octeon_irq_ciu1_rwlock, flags);
return 0;
}
#endif
static struct irq_chip octeon_irq_chip_ciu1 = {
.name = "CIU1",
.enable = octeon_irq_ciu1_enable,
.disable = octeon_irq_ciu1_disable,
.ack = octeon_irq_ciu1_ack,
.eoi = octeon_irq_ciu1_eoi,
#ifdef CONFIG_SMP
.set_affinity = octeon_irq_ciu1_set_affinity,
#endif
};
#ifdef CONFIG_PCI_MSI
static void octeon_irq_msi_ack(unsigned int irq)
{
if (!octeon_has_feature(OCTEON_FEATURE_PCIE)) {
/* These chips have PCI */
cvmx_write_csr(CVMX_NPI_NPI_MSI_RCV,
1ull << (irq - OCTEON_IRQ_MSI_BIT0));
} else {
/*
* These chips have PCIe. Thankfully the ACK doesn't
* need any locking.
*/
cvmx_write_csr(CVMX_PEXP_NPEI_MSI_RCV0,
1ull << (irq - OCTEON_IRQ_MSI_BIT0));
}
}
static void octeon_irq_msi_eoi(unsigned int irq)
{
/* Nothing needed */
}
static void octeon_irq_msi_enable(unsigned int irq)
{
if (!octeon_has_feature(OCTEON_FEATURE_PCIE)) {
/*
* Octeon PCI doesn't have the ability to mask/unmask
* MSI interrupts individually. Instead of
* masking/unmasking them in groups of 16, we simple
* assume MSI devices are well behaved. MSI
* interrupts are always enable and the ACK is assumed
* to be enough.
*/
} else {
/* These chips have PCIe. Note that we only support
* the first 64 MSI interrupts. Unfortunately all the
* MSI enables are in the same register. We use
* MSI0's lock to control access to them all.
*/
uint64_t en;
unsigned long flags;
spin_lock_irqsave(&octeon_irq_msi_lock, flags);
en = cvmx_read_csr(CVMX_PEXP_NPEI_MSI_ENB0);
en |= 1ull << (irq - OCTEON_IRQ_MSI_BIT0);
cvmx_write_csr(CVMX_PEXP_NPEI_MSI_ENB0, en);
cvmx_read_csr(CVMX_PEXP_NPEI_MSI_ENB0);
spin_unlock_irqrestore(&octeon_irq_msi_lock, flags);
}
}
static void octeon_irq_msi_disable(unsigned int irq)
{
if (!octeon_has_feature(OCTEON_FEATURE_PCIE)) {
/* See comment in enable */
} else {
/*
* These chips have PCIe. Note that we only support
* the first 64 MSI interrupts. Unfortunately all the
* MSI enables are in the same register. We use
* MSI0's lock to control access to them all.
*/
uint64_t en;
unsigned long flags;
spin_lock_irqsave(&octeon_irq_msi_lock, flags);
en = cvmx_read_csr(CVMX_PEXP_NPEI_MSI_ENB0);
en &= ~(1ull << (irq - OCTEON_IRQ_MSI_BIT0));
cvmx_write_csr(CVMX_PEXP_NPEI_MSI_ENB0, en);
cvmx_read_csr(CVMX_PEXP_NPEI_MSI_ENB0);
spin_unlock_irqrestore(&octeon_irq_msi_lock, flags);
}
}
static struct irq_chip octeon_irq_chip_msi = {
.name = "MSI",
.enable = octeon_irq_msi_enable,
.disable = octeon_irq_msi_disable,
.ack = octeon_irq_msi_ack,
.eoi = octeon_irq_msi_eoi,
};
#endif
void __init arch_init_irq(void)
{
int irq;
#ifdef CONFIG_SMP
/* Set the default affinity to the boot cpu. */
cpumask_clear(irq_default_affinity);
cpumask_set_cpu(smp_processor_id(), irq_default_affinity);
#endif
if (NR_IRQS < OCTEON_IRQ_LAST)
pr_err("octeon_irq_init: NR_IRQS is set too low\n");
/* 0 - 15 reserved for i8259 master and slave controller. */
/* 17 - 23 Mips internal */
for (irq = OCTEON_IRQ_SW0; irq <= OCTEON_IRQ_TIMER; irq++) {
set_irq_chip_and_handler(irq, &octeon_irq_chip_core,
handle_percpu_irq);
}
/* 24 - 87 CIU_INT_SUM0 */
for (irq = OCTEON_IRQ_WORKQ0; irq <= OCTEON_IRQ_BOOTDMA; irq++) {
set_irq_chip_and_handler(irq, &octeon_irq_chip_ciu0,
handle_percpu_irq);
}
/* 88 - 151 CIU_INT_SUM1 */
for (irq = OCTEON_IRQ_WDOG0; irq <= OCTEON_IRQ_RESERVED151; irq++) {
set_irq_chip_and_handler(irq, &octeon_irq_chip_ciu1,
handle_percpu_irq);
}
#ifdef CONFIG_PCI_MSI
/* 152 - 215 PCI/PCIe MSI interrupts */
for (irq = OCTEON_IRQ_MSI_BIT0; irq <= OCTEON_IRQ_MSI_BIT63; irq++) {
set_irq_chip_and_handler(irq, &octeon_irq_chip_msi,
handle_percpu_irq);
}
#endif
set_c0_status(0x300 << 2);
}
asmlinkage void plat_irq_dispatch(void)
{
const unsigned long core_id = cvmx_get_core_num();
const uint64_t ciu_sum0_address = CVMX_CIU_INTX_SUM0(core_id * 2);
const uint64_t ciu_en0_address = CVMX_CIU_INTX_EN0(core_id * 2);
const uint64_t ciu_sum1_address = CVMX_CIU_INT_SUM1;
const uint64_t ciu_en1_address = CVMX_CIU_INTX_EN1(core_id * 2 + 1);
unsigned long cop0_cause;
unsigned long cop0_status;
uint64_t ciu_en;
uint64_t ciu_sum;
while (1) {
cop0_cause = read_c0_cause();
cop0_status = read_c0_status();
cop0_cause &= cop0_status;
cop0_cause &= ST0_IM;
if (unlikely(cop0_cause & STATUSF_IP2)) {
ciu_sum = cvmx_read_csr(ciu_sum0_address);
ciu_en = cvmx_read_csr(ciu_en0_address);
ciu_sum &= ciu_en;
if (likely(ciu_sum))
do_IRQ(fls64(ciu_sum) + OCTEON_IRQ_WORKQ0 - 1);
else
spurious_interrupt();
} else if (unlikely(cop0_cause & STATUSF_IP3)) {
ciu_sum = cvmx_read_csr(ciu_sum1_address);
ciu_en = cvmx_read_csr(ciu_en1_address);
ciu_sum &= ciu_en;
if (likely(ciu_sum))
do_IRQ(fls64(ciu_sum) + OCTEON_IRQ_WDOG0 - 1);
else
spurious_interrupt();
} else if (likely(cop0_cause)) {
do_IRQ(fls(cop0_cause) - 9 + MIPS_CPU_IRQ_BASE);
} else {
break;
}
}
}
#ifdef CONFIG_HOTPLUG_CPU
static int is_irq_enabled_on_cpu(unsigned int irq, unsigned int cpu)
{
unsigned int isset;
#ifdef CONFIG_SMP
int coreid = cpu_logical_map(cpu);
#else
int coreid = cvmx_get_core_num();
#endif
int bit = (irq < OCTEON_IRQ_WDOG0) ?
irq - OCTEON_IRQ_WORKQ0 : irq - OCTEON_IRQ_WDOG0;
if (irq < 64) {
isset = (cvmx_read_csr(CVMX_CIU_INTX_EN0(coreid * 2)) &
(1ull << bit)) >> bit;
} else {
isset = (cvmx_read_csr(CVMX_CIU_INTX_EN1(coreid * 2 + 1)) &
(1ull << bit)) >> bit;
}
return isset;
}
void fixup_irqs(void)
{
int irq;
for (irq = OCTEON_IRQ_SW0; irq <= OCTEON_IRQ_TIMER; irq++)
octeon_irq_core_disable_local(irq);
for (irq = OCTEON_IRQ_WORKQ0; irq <= OCTEON_IRQ_GPIO15; irq++) {
if (is_irq_enabled_on_cpu(irq, smp_processor_id())) {
/* ciu irq migrates to next cpu */
octeon_irq_chip_ciu0.disable(irq);
octeon_irq_ciu0_set_affinity(irq, &cpu_online_map);
}
}
#if 0
for (irq = OCTEON_IRQ_MBOX0; irq <= OCTEON_IRQ_MBOX1; irq++)
octeon_irq_mailbox_mask(irq);
#endif
for (irq = OCTEON_IRQ_UART0; irq <= OCTEON_IRQ_BOOTDMA; irq++) {
if (is_irq_enabled_on_cpu(irq, smp_processor_id())) {
/* ciu irq migrates to next cpu */
octeon_irq_chip_ciu0.disable(irq);
octeon_irq_ciu0_set_affinity(irq, &cpu_online_map);
}
}
for (irq = OCTEON_IRQ_UART2; irq <= OCTEON_IRQ_RESERVED135; irq++) {
if (is_irq_enabled_on_cpu(irq, smp_processor_id())) {
/* ciu irq migrates to next cpu */
octeon_irq_chip_ciu1.disable(irq);
octeon_irq_ciu1_set_affinity(irq, &cpu_online_map);
}
}
}
#endif /* CONFIG_HOTPLUG_CPU */