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-rw-r--r--arch/mips/cavium-octeon/octeon-irq.c497
1 files changed, 497 insertions, 0 deletions
diff --git a/arch/mips/cavium-octeon/octeon-irq.c b/arch/mips/cavium-octeon/octeon-irq.c
new file mode 100644
index 000000000000..fc72984a5dae
--- /dev/null
+++ b/arch/mips/cavium-octeon/octeon-irq.c
@@ -0,0 +1,497 @@
+/*
+ * 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/hardirq.h>
+
+#include <asm/octeon/octeon.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)
+{
+ irq_desc_t *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 void octeon_irq_ciu0_set_affinity(unsigned int irq, const struct cpumask *dest)
+{
+ int cpu;
+ int bit = irq - OCTEON_IRQ_WORKQ0; /* Bit 0-63 of EN0 */
+
+ write_lock(&octeon_irq_ciu0_rwlock);
+ 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(&octeon_irq_ciu0_rwlock);
+}
+#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 void octeon_irq_ciu1_set_affinity(unsigned int irq, const struct cpumask *dest)
+{
+ int cpu;
+ int bit = irq - OCTEON_IRQ_WDOG0; /* Bit 0-63 of EN1 */
+
+ write_lock(&octeon_irq_ciu1_rwlock);
+ 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(&octeon_irq_ciu1_rwlock);
+}
+#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;
+ }
+ }
+}