From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932926AbcH3Rea (ORCPT ); Tue, 30 Aug 2016 13:34:30 -0400 Received: from mailapp01.imgtec.com ([195.59.15.196]:13892 "EHLO mailapp01.imgtec.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758716AbcH3Re0 (ORCPT ); Tue, 30 Aug 2016 13:34:26 -0400 From: Paul Burton To: , Ralf Baechle CC: Paul Burton , Marc Zyngier , Jason Cooper , Thomas Gleixner , Subject: [PATCH v2 17/26] irqchip: mips-cpu: Introduce IPI IRQ domain support Date: Tue, 30 Aug 2016 18:29:20 +0100 Message-ID: <20160830172929.16948-18-paul.burton@imgtec.com> X-Mailer: git-send-email 2.9.3 In-Reply-To: <20160830172929.16948-1-paul.burton@imgtec.com> References: <20160830172929.16948-1-paul.burton@imgtec.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.100.200.118] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Introduce support for registering an IPI IRQ domain suitable for use by systems using the MIPS MT (multithreading) ASE within a single core. This will allow for such systems to be supported generically, without the current kludge of IPI code split between the MIPS arch & the malta board support code. Signed-off-by: Paul Burton --- Changes in v2: None drivers/irqchip/Kconfig | 2 + drivers/irqchip/irq-mips-cpu.c | 128 ++++++++++++++++++++++++++++++++++++++--- 2 files changed, 122 insertions(+), 8 deletions(-) diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig index 7f87289..8af8704 100644 --- a/drivers/irqchip/Kconfig +++ b/drivers/irqchip/Kconfig @@ -127,7 +127,9 @@ config IMGPDC_IRQ config IRQ_MIPS_CPU bool select GENERIC_IRQ_CHIP + select GENERIC_IRQ_IPI if SYS_SUPPORTS_MULTITHREADING select IRQ_DOMAIN + select IRQ_DOMAIN_HIERARCHY if GENERIC_IRQ_IPI config CLPS711X_IRQCHIP bool diff --git a/drivers/irqchip/irq-mips-cpu.c b/drivers/irqchip/irq-mips-cpu.c index 338de92..8108257 100644 --- a/drivers/irqchip/irq-mips-cpu.c +++ b/drivers/irqchip/irq-mips-cpu.c @@ -17,15 +17,14 @@ /* * Almost all MIPS CPUs define 8 interrupt sources. They are typically * level triggered (i.e., cannot be cleared from CPU; must be cleared from - * device). The first two are software interrupts which we don't really - * use or support. The last one is usually the CPU timer interrupt if - * counter register is present or, for CPUs with an external FPU, by - * convention it's the FPU exception interrupt. + * device). * - * Don't even think about using this on SMP. You have been warned. + * The first two are software interrupts (i.e. not exposed as pins) which + * may be used for IPIs in multi-threaded single-core systems. * - * This file exports one global function: - * void mips_cpu_irq_init(void); + * The last one is usually the CPU timer interrupt if the counter register + * is present, or for old CPUs with an external FPU by convention it's the + * FPU exception interrupt. */ #include #include @@ -40,6 +39,7 @@ #include static struct irq_domain *irq_domain; +static struct irq_domain *ipi_domain; static inline void unmask_mips_irq(struct irq_data *d) { @@ -90,6 +90,29 @@ static void mips_mt_cpu_irq_ack(struct irq_data *d) mask_mips_irq(d); } +#ifdef CONFIG_GENERIC_IRQ_IPI + +static void mips_mt_send_ipi(struct irq_data *d, unsigned int cpu) +{ + irq_hw_number_t hwirq = irqd_to_hwirq(d); + unsigned long flags; + int vpflags; + + local_irq_save(flags); + + /* We can only send IPIs to VPEs within the local core */ + BUG_ON(cpu_data[cpu].core != current_cpu_data.core); + + vpflags = dvpe(); + settc(cpu_vpe_id(&cpu_data[cpu])); + write_vpe_c0_cause(read_vpe_c0_cause() | (C_SW0 << hwirq)); + evpe(vpflags); + + local_irq_restore(flags); +} + +#endif /* CONFIG_GENERIC_IRQ_IPI */ + static struct irq_chip mips_mt_cpu_irq_controller = { .name = "MIPS", .irq_startup = mips_mt_cpu_irq_startup, @@ -100,6 +123,9 @@ static struct irq_chip mips_mt_cpu_irq_controller = { .irq_eoi = unmask_mips_irq, .irq_disable = mask_mips_irq, .irq_enable = unmask_mips_irq, +#ifdef CONFIG_GENERIC_IRQ_IPI + .ipi_send_single= mips_mt_send_ipi, +#endif }; asmlinkage void __weak plat_irq_dispatch(void) @@ -116,7 +142,10 @@ asmlinkage void __weak plat_irq_dispatch(void) pending >>= CAUSEB_IP; while (pending) { irq = fls(pending) - 1; - virq = irq_linear_revmap(irq_domain, irq); + if (IS_ENABLED(CONFIG_GENERIC_IRQ_IPI) && irq < 2) + virq = irq_linear_revmap(ipi_domain, irq); + else + virq = irq_linear_revmap(irq_domain, irq); do_IRQ(virq); pending &= ~BIT(irq); } @@ -147,6 +176,82 @@ static const struct irq_domain_ops mips_cpu_intc_irq_domain_ops = { .xlate = irq_domain_xlate_onecell, }; +#ifdef CONFIG_GENERIC_IRQ_IPI + +struct cpu_ipi_domain_state { + DECLARE_BITMAP(allocated, 2); +}; + +static int mips_cpu_ipi_alloc(struct irq_domain *domain, unsigned int virq, + unsigned int nr_irqs, void *arg) +{ + struct cpu_ipi_domain_state *state = domain->host_data; + unsigned int i, hwirq; + int ret; + + for (i = 0; i < nr_irqs; i++) { + hwirq = find_first_zero_bit(state->allocated, 2); + if (hwirq == 2) + return -EBUSY; + bitmap_set(state->allocated, hwirq, 1); + + ret = irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq, + &mips_mt_cpu_irq_controller, + NULL); + if (ret) + return ret; + + ret = irq_set_irq_type(virq + i, IRQ_TYPE_LEVEL_HIGH); + if (ret) + return ret; + } + + return 0; +} + +static int mips_cpu_ipi_match(struct irq_domain *d, struct device_node *node, + enum irq_domain_bus_token bus_token) +{ + bool is_ipi; + + switch (bus_token) { + case DOMAIN_BUS_IPI: + is_ipi = d->bus_token == bus_token; + return (!node || (to_of_node(d->fwnode) == node)) && is_ipi; + default: + return 0; + } +} + +static const struct irq_domain_ops mips_cpu_ipi_chip_ops = { + .alloc = mips_cpu_ipi_alloc, + .match = mips_cpu_ipi_match, +}; + +static void mips_cpu_register_ipi_domain(struct device_node *of_node) +{ + struct cpu_ipi_domain_state *ipi_domain_state; + + ipi_domain_state = kzalloc(sizeof(*ipi_domain_state), GFP_KERNEL); + if (!ipi_domain_state) + panic("Failed to alloc IPI domain state"); + + ipi_domain = irq_domain_add_hierarchy(irq_domain, + IRQ_DOMAIN_FLAG_IPI_SINGLE, + 2, of_node, + &mips_cpu_ipi_chip_ops, + ipi_domain_state); + if (!ipi_domain) + panic("Failed to add MIPS CPU IPI domain"); + ipi_domain->bus_token = DOMAIN_BUS_IPI; +} + +#else /* !CONFIG_GENERIC_IRQ_IPI */ + +static inline void mips_cpu_register_ipi_domain(struct device_node *of_node) {} + +#endif /* !CONFIG_GENERIC_IRQ_IPI */ + static void __init __mips_cpu_irq_init(struct device_node *of_node) { /* Mask interrupts. */ @@ -158,6 +263,13 @@ static void __init __mips_cpu_irq_init(struct device_node *of_node) NULL); if (!irq_domain) panic("Failed to add irqdomain for MIPS CPU"); + + /* + * Only proceed to register the software interrupt IPI implementation + * for CPUs which implement the MIPS MT (multi-threading) ASE. + */ + if (cpu_has_mipsmt) + mips_cpu_register_ipi_domain(of_node); } void __init mips_cpu_irq_init(void) -- 2.9.3 From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailapp01.imgtec.com ([195.59.15.196]:41215 "EHLO mailapp01.imgtec.com" rhost-flags-OK-OK-OK-OK) by eddie.linux-mips.org with ESMTP id S23992255AbcH3ReaQNuu0 (ORCPT ); Tue, 30 Aug 2016 19:34:30 +0200 From: Paul Burton Subject: [PATCH v2 17/26] irqchip: mips-cpu: Introduce IPI IRQ domain support Date: Tue, 30 Aug 2016 18:29:20 +0100 Message-ID: <20160830172929.16948-18-paul.burton@imgtec.com> In-Reply-To: <20160830172929.16948-1-paul.burton@imgtec.com> References: <20160830172929.16948-1-paul.burton@imgtec.com> MIME-Version: 1.0 Content-Type: text/plain Return-Path: Sender: linux-mips-bounce@linux-mips.org Errors-to: linux-mips-bounce@linux-mips.org List-help: List-unsubscribe: List-software: Ecartis version 1.0.0 List-subscribe: List-owner: List-post: List-archive: To: linux-mips@linux-mips.org, Ralf Baechle Cc: Paul Burton , Marc Zyngier , Jason Cooper , Thomas Gleixner , linux-kernel@vger.kernel.org Message-ID: <20160830172920.OfmXdv_MUMZbt5wpdJLX8gfzndsvdHztg_FM6kjK38M@z> Introduce support for registering an IPI IRQ domain suitable for use by systems using the MIPS MT (multithreading) ASE within a single core. This will allow for such systems to be supported generically, without the current kludge of IPI code split between the MIPS arch & the malta board support code. Signed-off-by: Paul Burton --- Changes in v2: None drivers/irqchip/Kconfig | 2 + drivers/irqchip/irq-mips-cpu.c | 128 ++++++++++++++++++++++++++++++++++++++--- 2 files changed, 122 insertions(+), 8 deletions(-) diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig index 7f87289..8af8704 100644 --- a/drivers/irqchip/Kconfig +++ b/drivers/irqchip/Kconfig @@ -127,7 +127,9 @@ config IMGPDC_IRQ config IRQ_MIPS_CPU bool select GENERIC_IRQ_CHIP + select GENERIC_IRQ_IPI if SYS_SUPPORTS_MULTITHREADING select IRQ_DOMAIN + select IRQ_DOMAIN_HIERARCHY if GENERIC_IRQ_IPI config CLPS711X_IRQCHIP bool diff --git a/drivers/irqchip/irq-mips-cpu.c b/drivers/irqchip/irq-mips-cpu.c index 338de92..8108257 100644 --- a/drivers/irqchip/irq-mips-cpu.c +++ b/drivers/irqchip/irq-mips-cpu.c @@ -17,15 +17,14 @@ /* * Almost all MIPS CPUs define 8 interrupt sources. They are typically * level triggered (i.e., cannot be cleared from CPU; must be cleared from - * device). The first two are software interrupts which we don't really - * use or support. The last one is usually the CPU timer interrupt if - * counter register is present or, for CPUs with an external FPU, by - * convention it's the FPU exception interrupt. + * device). * - * Don't even think about using this on SMP. You have been warned. + * The first two are software interrupts (i.e. not exposed as pins) which + * may be used for IPIs in multi-threaded single-core systems. * - * This file exports one global function: - * void mips_cpu_irq_init(void); + * The last one is usually the CPU timer interrupt if the counter register + * is present, or for old CPUs with an external FPU by convention it's the + * FPU exception interrupt. */ #include #include @@ -40,6 +39,7 @@ #include static struct irq_domain *irq_domain; +static struct irq_domain *ipi_domain; static inline void unmask_mips_irq(struct irq_data *d) { @@ -90,6 +90,29 @@ static void mips_mt_cpu_irq_ack(struct irq_data *d) mask_mips_irq(d); } +#ifdef CONFIG_GENERIC_IRQ_IPI + +static void mips_mt_send_ipi(struct irq_data *d, unsigned int cpu) +{ + irq_hw_number_t hwirq = irqd_to_hwirq(d); + unsigned long flags; + int vpflags; + + local_irq_save(flags); + + /* We can only send IPIs to VPEs within the local core */ + BUG_ON(cpu_data[cpu].core != current_cpu_data.core); + + vpflags = dvpe(); + settc(cpu_vpe_id(&cpu_data[cpu])); + write_vpe_c0_cause(read_vpe_c0_cause() | (C_SW0 << hwirq)); + evpe(vpflags); + + local_irq_restore(flags); +} + +#endif /* CONFIG_GENERIC_IRQ_IPI */ + static struct irq_chip mips_mt_cpu_irq_controller = { .name = "MIPS", .irq_startup = mips_mt_cpu_irq_startup, @@ -100,6 +123,9 @@ static struct irq_chip mips_mt_cpu_irq_controller = { .irq_eoi = unmask_mips_irq, .irq_disable = mask_mips_irq, .irq_enable = unmask_mips_irq, +#ifdef CONFIG_GENERIC_IRQ_IPI + .ipi_send_single= mips_mt_send_ipi, +#endif }; asmlinkage void __weak plat_irq_dispatch(void) @@ -116,7 +142,10 @@ asmlinkage void __weak plat_irq_dispatch(void) pending >>= CAUSEB_IP; while (pending) { irq = fls(pending) - 1; - virq = irq_linear_revmap(irq_domain, irq); + if (IS_ENABLED(CONFIG_GENERIC_IRQ_IPI) && irq < 2) + virq = irq_linear_revmap(ipi_domain, irq); + else + virq = irq_linear_revmap(irq_domain, irq); do_IRQ(virq); pending &= ~BIT(irq); } @@ -147,6 +176,82 @@ static const struct irq_domain_ops mips_cpu_intc_irq_domain_ops = { .xlate = irq_domain_xlate_onecell, }; +#ifdef CONFIG_GENERIC_IRQ_IPI + +struct cpu_ipi_domain_state { + DECLARE_BITMAP(allocated, 2); +}; + +static int mips_cpu_ipi_alloc(struct irq_domain *domain, unsigned int virq, + unsigned int nr_irqs, void *arg) +{ + struct cpu_ipi_domain_state *state = domain->host_data; + unsigned int i, hwirq; + int ret; + + for (i = 0; i < nr_irqs; i++) { + hwirq = find_first_zero_bit(state->allocated, 2); + if (hwirq == 2) + return -EBUSY; + bitmap_set(state->allocated, hwirq, 1); + + ret = irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq, + &mips_mt_cpu_irq_controller, + NULL); + if (ret) + return ret; + + ret = irq_set_irq_type(virq + i, IRQ_TYPE_LEVEL_HIGH); + if (ret) + return ret; + } + + return 0; +} + +static int mips_cpu_ipi_match(struct irq_domain *d, struct device_node *node, + enum irq_domain_bus_token bus_token) +{ + bool is_ipi; + + switch (bus_token) { + case DOMAIN_BUS_IPI: + is_ipi = d->bus_token == bus_token; + return (!node || (to_of_node(d->fwnode) == node)) && is_ipi; + default: + return 0; + } +} + +static const struct irq_domain_ops mips_cpu_ipi_chip_ops = { + .alloc = mips_cpu_ipi_alloc, + .match = mips_cpu_ipi_match, +}; + +static void mips_cpu_register_ipi_domain(struct device_node *of_node) +{ + struct cpu_ipi_domain_state *ipi_domain_state; + + ipi_domain_state = kzalloc(sizeof(*ipi_domain_state), GFP_KERNEL); + if (!ipi_domain_state) + panic("Failed to alloc IPI domain state"); + + ipi_domain = irq_domain_add_hierarchy(irq_domain, + IRQ_DOMAIN_FLAG_IPI_SINGLE, + 2, of_node, + &mips_cpu_ipi_chip_ops, + ipi_domain_state); + if (!ipi_domain) + panic("Failed to add MIPS CPU IPI domain"); + ipi_domain->bus_token = DOMAIN_BUS_IPI; +} + +#else /* !CONFIG_GENERIC_IRQ_IPI */ + +static inline void mips_cpu_register_ipi_domain(struct device_node *of_node) {} + +#endif /* !CONFIG_GENERIC_IRQ_IPI */ + static void __init __mips_cpu_irq_init(struct device_node *of_node) { /* Mask interrupts. */ @@ -158,6 +263,13 @@ static void __init __mips_cpu_irq_init(struct device_node *of_node) NULL); if (!irq_domain) panic("Failed to add irqdomain for MIPS CPU"); + + /* + * Only proceed to register the software interrupt IPI implementation + * for CPUs which implement the MIPS MT (multi-threading) ASE. + */ + if (cpu_has_mipsmt) + mips_cpu_register_ipi_domain(of_node); } void __init mips_cpu_irq_init(void) -- 2.9.3