diff options
| -rw-r--r-- | Documentation/devicetree/bindings/arc/archs-intc.txt | 22 | ||||
| -rw-r--r-- | arch/arc/include/asm/arcregs.h | 1 | ||||
| -rw-r--r-- | arch/arc/include/asm/irqflags-arcv2.h | 116 | ||||
| -rw-r--r-- | arch/arc/kernel/intc-arcv2.c | 143 |
4 files changed, 282 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/arc/archs-intc.txt b/Documentation/devicetree/bindings/arc/archs-intc.txt new file mode 100644 index 000000000000..69f326d6a5ad --- /dev/null +++ b/Documentation/devicetree/bindings/arc/archs-intc.txt @@ -0,0 +1,22 @@ +* ARC-HS incore Interrupt Controller (Provided by cores implementing ARCv2 ISA) + +Properties: + +- compatible: "snps,archs-intc" +- interrupt-controller: This is an interrupt controller. +- #interrupt-cells: Must be <1>. + + Single Cell "interrupts" property of a device specifies the IRQ number + between 16 to 256 + + intc accessed via the special ARC AUX register interface, hence "reg" property + is not specified. + +Example: + + intc: interrupt-controller { + compatible = "snps,archs-intc"; + interrupt-controller; + #interrupt-cells = <1>; + interrupts = <16 17 18 19 20 21 22 23 24 25>; + }; diff --git a/arch/arc/include/asm/arcregs.h b/arch/arc/include/asm/arcregs.h index 336a9f694c2e..649646579986 100644 --- a/arch/arc/include/asm/arcregs.h +++ b/arch/arc/include/asm/arcregs.h @@ -31,6 +31,7 @@ #define ARC_REG_BPU_BCR 0xc0 #define ARC_REG_ISA_CFG_BCR 0xc1 #define ARC_REG_RTT_BCR 0xF2 +#define ARC_REG_IRQ_BCR 0xF3 #define ARC_REG_SMART_BCR 0xFF /* status32 Bits Positions */ diff --git a/arch/arc/include/asm/irqflags-arcv2.h b/arch/arc/include/asm/irqflags-arcv2.h new file mode 100644 index 000000000000..c946c56f141c --- /dev/null +++ b/arch/arc/include/asm/irqflags-arcv2.h @@ -0,0 +1,116 @@ +/* + * Copyright (C) 2014-15 Synopsys, Inc. (www.synopsys.com) + * + * 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. + */ + +#ifndef __ASM_IRQFLAGS_ARCV2_H +#define __ASM_IRQFLAGS_ARCV2_H + +#include <asm/arcregs.h> + +/* status32 Bits */ +#define STATUS_AD_BIT 19 /* Disable Align chk: core supports non-aligned */ +#define STATUS_IE_BIT 31 + +#define STATUS_AD_MASK (1<<STATUS_AD_BIT) +#define STATUS_IE_MASK (1<<STATUS_IE_BIT) + +#define AUX_USER_SP 0x00D +#define AUX_IRQ_CTRL 0x00E +#define AUX_IRQ_ACT 0x043 /* Active Intr across all levels */ +#define AUX_IRQ_LVL_PEND 0x200 /* Pending Intr across all levels */ +#define AUX_IRQ_PRIORITY 0x206 +#define ICAUSE 0x40a +#define AUX_IRQ_SELECT 0x40b +#define AUX_IRQ_ENABLE 0x40c + +/* 0 is highest level, but taken by FIRQs, if present in design */ +#define ARCV2_IRQ_DEF_PRIO 0 + +/* seed value for status register */ +#define ISA_INIT_STATUS_BITS (STATUS_IE_MASK | STATUS_AD_MASK | \ + (ARCV2_IRQ_DEF_PRIO << 1)) + +#ifndef __ASSEMBLY__ + +/* + * Save IRQ state and disable IRQs + */ +static inline long arch_local_irq_save(void) +{ + unsigned long flags; + + __asm__ __volatile__(" clri %0 \n" : "=r" (flags) : : "memory"); + + return flags; +} + +/* + * restore saved IRQ state + */ +static inline void arch_local_irq_restore(unsigned long flags) +{ + __asm__ __volatile__(" seti %0 \n" : : "r" (flags) : "memory"); +} + +/* + * Unconditionally Enable IRQs + */ +static inline void arch_local_irq_enable(void) +{ + __asm__ __volatile__(" seti \n" : : : "memory"); +} + +/* + * Unconditionally Disable IRQs + */ +static inline void arch_local_irq_disable(void) +{ + __asm__ __volatile__(" clri \n" : : : "memory"); +} + +/* + * save IRQ state + */ +static inline long arch_local_save_flags(void) +{ + unsigned long temp; + + __asm__ __volatile__( + " lr %0, [status32] \n" + : "=&r"(temp) + : + : "memory"); + + return temp; +} + +/* + * Query IRQ state + */ +static inline int arch_irqs_disabled_flags(unsigned long flags) +{ + return !(flags & (STATUS_IE_MASK)); +} + +static inline int arch_irqs_disabled(void) +{ + return arch_irqs_disabled_flags(arch_local_save_flags()); +} + +#else + +.macro IRQ_DISABLE scratch + clri +.endm + +.macro IRQ_ENABLE scratch + seti +.endm + +#endif /* __ASSEMBLY__ */ + +#endif diff --git a/arch/arc/kernel/intc-arcv2.c b/arch/arc/kernel/intc-arcv2.c new file mode 100644 index 000000000000..c5c64dc47655 --- /dev/null +++ b/arch/arc/kernel/intc-arcv2.c @@ -0,0 +1,143 @@ +/* + * Copyright (C) 2014 Synopsys, Inc. (www.synopsys.com) + * + * 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. + * + */ + +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/irqdomain.h> +#include <linux/irqchip.h> +#include "../../drivers/irqchip/irqchip.h" +#include <asm/irq.h> + +/* + * Early Hardware specific Interrupt setup + * -Called very early (start_kernel -> setup_arch -> setup_processor) + * -Platform Independent (must for any ARC Core) + * -Needed for each CPU (hence not foldable into init_IRQ) + */ +void arc_init_IRQ(void) +{ + unsigned int tmp; + + struct aux_irq_ctrl { +#ifdef CONFIG_CPU_BIG_ENDIAN + unsigned int res3:18, save_idx_regs:1, res2:1, + save_u_to_u:1, save_lp_regs:1, save_blink:1, + res:4, save_nr_gpr_pairs:5; +#else + unsigned int save_nr_gpr_pairs:5, res:4, + save_blink:1, save_lp_regs:1, save_u_to_u:1, + res2:1, save_idx_regs:1, res3:18; +#endif + } ictrl; + + *(unsigned int *)&ictrl = 0; + + ictrl.save_nr_gpr_pairs = 6; /* r0 to r11 (r12 saved manually) */ + ictrl.save_blink = 1; + ictrl.save_lp_regs = 1; /* LP_COUNT, LP_START, LP_END */ + ictrl.save_u_to_u = 0; /* user ctxt saved on kernel stack */ + ictrl.save_idx_regs = 1; /* JLI, LDI, EI */ + + WRITE_AUX(AUX_IRQ_CTRL, ictrl); + + /* setup status32, don't enable intr yet as kernel doesn't want */ + tmp = read_aux_reg(0xa); + tmp |= ISA_INIT_STATUS_BITS; + tmp &= ~STATUS_IE_MASK; + asm volatile("flag %0 \n"::"r"(tmp)); + + /* + * ARCv2 core intc provides multiple interrupt priorities (upto 16). + * Typical builds though have only two levels (0-high, 1-low) + * Linux by default uses lower prio 1 for most irqs, reserving 0 for + * NMI style interrupts in future (say perf) + * + * Read the intc BCR to confirm that Linux default priority is avail + * in h/w + * + * Note: + * IRQ_BCR[27..24] contains N-1 (for N priority levels) and prio level + * is 0 based. + */ + tmp = (read_aux_reg(ARC_REG_IRQ_BCR) >> 24 ) & 0xF; + if (ARCV2_IRQ_DEF_PRIO > tmp) + panic("Linux default irq prio incorrect\n"); +} + +static void arcv2_irq_mask(struct irq_data *data) +{ + write_aux_reg(AUX_IRQ_SELECT, data->irq); + write_aux_reg(AUX_IRQ_ENABLE, 0); +} + +static void arcv2_irq_unmask(struct irq_data *data) +{ + write_aux_reg(AUX_IRQ_SELECT, data->irq); + write_aux_reg(AUX_IRQ_ENABLE, 1); +} + +void arcv2_irq_enable(struct irq_data *data) +{ + /* set default priority */ + write_aux_reg(AUX_IRQ_SELECT, data->irq); + write_aux_reg(AUX_IRQ_PRIORITY, ARCV2_IRQ_DEF_PRIO); + + /* + * hw auto enables (linux unmask) all by default + * So no need to do IRQ_ENABLE here + * XXX: However OSCI LAN need it + */ + write_aux_reg(AUX_IRQ_ENABLE, 1); +} + +static struct irq_chip arcv2_irq_chip = { + .name = "ARCv2 core Intc", + .irq_mask = arcv2_irq_mask, + .irq_unmask = arcv2_irq_unmask, + .irq_enable = arcv2_irq_enable +}; + +static int arcv2_irq_map(struct irq_domain *d, unsigned int irq, + irq_hw_number_t hw) +{ + if (irq == TIMER0_IRQ) + irq_set_chip_and_handler(irq, &arcv2_irq_chip, handle_percpu_irq); + else + irq_set_chip_and_handler(irq, &arcv2_irq_chip, handle_level_irq); + + return 0; +} + +static const struct irq_domain_ops arcv2_irq_ops = { + .xlate = irq_domain_xlate_onecell, + .map = arcv2_irq_map, +}; + +static struct irq_domain *root_domain; + +static int __init +init_onchip_IRQ(struct device_node *intc, struct device_node *parent) +{ + if (parent) + panic("DeviceTree incore intc not a root irq controller\n"); + + root_domain = irq_domain_add_legacy(intc, NR_CPU_IRQS, 0, 0, + &arcv2_irq_ops, NULL); + + if (!root_domain) + panic("root irq domain not avail\n"); + + /* with this we don't need to export root_domain */ + irq_set_default_host(root_domain); + + return 0; +} + +IRQCHIP_DECLARE(arc_intc, "snps,archs-intc", init_onchip_IRQ); |