diff options
Diffstat (limited to 'arch/mips/cavium-octeon/octeon-irq.c')
| -rw-r--r-- | arch/mips/cavium-octeon/octeon-irq.c | 497 |
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; + } + } +} |