From 4c18e77f718cdda33363132127db4df795eadbd9 Mon Sep 17 00:00:00 2001 From: viresh kumar Date: Mon, 3 May 2010 09:24:30 +0100 Subject: ARM: 6091/1: ST SPEAr: Adding support for shared irq layer Multiple peripherals in SPEAr share common hardware interrupt lines. This patch adds support for a shared irq layer, which registers hardware irqs by itself and exposes virtual irq numbers to peripherals. Signed-off-by: Viresh Kumar Signed-off-by: Russell King --- arch/arm/plat-spear/Makefile | 2 + arch/arm/plat-spear/include/plat/shirq.h | 73 +++++++++++++++++++ arch/arm/plat-spear/shirq.c | 118 +++++++++++++++++++++++++++++++ 3 files changed, 193 insertions(+) create mode 100644 arch/arm/plat-spear/include/plat/shirq.h create mode 100644 arch/arm/plat-spear/shirq.c (limited to 'arch/arm/plat-spear') diff --git a/arch/arm/plat-spear/Makefile b/arch/arm/plat-spear/Makefile index 6f4ad5e..eb89540 100644 --- a/arch/arm/plat-spear/Makefile +++ b/arch/arm/plat-spear/Makefile @@ -4,3 +4,5 @@ # Common support obj-y := clock.o padmux.o time.o + +obj-$(CONFIG_ARCH_SPEAR3XX) += shirq.o diff --git a/arch/arm/plat-spear/include/plat/shirq.h b/arch/arm/plat-spear/include/plat/shirq.h new file mode 100644 index 0000000..03ed8b5 --- /dev/null +++ b/arch/arm/plat-spear/include/plat/shirq.h @@ -0,0 +1,73 @@ +/* + * arch/arm/plat-spear/include/plat/shirq.h + * + * SPEAr platform shared irq layer header file + * + * Copyright (C) 2009 ST Microelectronics + * Viresh Kumar + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#ifndef __PLAT_SHIRQ_H +#define __PLAT_SHIRQ_H + +#include +#include + +/* + * struct shirq_dev_config: shared irq device configuration + * + * virq: virtual irq number of device + * enb_mask: enable mask of device + * status_mask: status mask of device + * clear_mask: clear mask of device + */ +struct shirq_dev_config { + u32 virq; + u32 enb_mask; + u32 status_mask; + u32 clear_mask; +}; + +/* + * struct shirq_regs: shared irq register configuration + * + * base: base address of shared irq register + * enb_reg: enable register offset + * reset_to_enb: val 1 indicates, we need to clear bit for enabling interrupt + * status_reg: status register offset + * status_reg_mask: status register valid mask + * clear_reg: clear register offset + * reset_to_clear: val 1 indicates, we need to clear bit for clearing interrupt + */ +struct shirq_regs { + void __iomem *base; + u32 enb_reg; + u32 reset_to_enb; + u32 status_reg; + u32 status_reg_mask; + u32 clear_reg; + u32 reset_to_clear; +}; + +/* + * struct spear_shirq: shared irq structure + * + * irq: hardware irq number + * dev_config: array of device config structures which are using "irq" line + * dev_count: size of dev_config array + * regs: register configuration for shared irq block + */ +struct spear_shirq { + u32 irq; + struct shirq_dev_config *dev_config; + u32 dev_count; + struct shirq_regs regs; +}; + +int spear_shirq_register(struct spear_shirq *shirq); + +#endif /* __PLAT_SHIRQ_H */ diff --git a/arch/arm/plat-spear/shirq.c b/arch/arm/plat-spear/shirq.c new file mode 100644 index 0000000..2172d69 --- /dev/null +++ b/arch/arm/plat-spear/shirq.c @@ -0,0 +1,118 @@ +/* + * arch/arm/plat-spear/shirq.c + * + * SPEAr platform shared irq layer source file + * + * Copyright (C) 2009 ST Microelectronics + * Viresh Kumar + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#include +#include +#include +#include +#include + +struct spear_shirq *shirq; +static DEFINE_SPINLOCK(lock); + +static void shirq_irq_mask(unsigned irq) +{ + struct spear_shirq *shirq = get_irq_chip_data(irq); + u32 val, id = irq - shirq->dev_config[0].virq; + unsigned long flags; + + if ((shirq->regs.enb_reg == -1) || shirq->dev_config[id].enb_mask == -1) + return; + + spin_lock_irqsave(&lock, flags); + val = readl(shirq->regs.base + shirq->regs.enb_reg); + if (shirq->regs.reset_to_enb) + val |= shirq->dev_config[id].enb_mask; + else + val &= ~(shirq->dev_config[id].enb_mask); + writel(val, shirq->regs.base + shirq->regs.enb_reg); + spin_unlock_irqrestore(&lock, flags); +} + +static void shirq_irq_unmask(unsigned irq) +{ + struct spear_shirq *shirq = get_irq_chip_data(irq); + u32 val, id = irq - shirq->dev_config[0].virq; + unsigned long flags; + + if ((shirq->regs.enb_reg == -1) || shirq->dev_config[id].enb_mask == -1) + return; + + spin_lock_irqsave(&lock, flags); + val = readl(shirq->regs.base + shirq->regs.enb_reg); + if (shirq->regs.reset_to_enb) + val &= ~(shirq->dev_config[id].enb_mask); + else + val |= shirq->dev_config[id].enb_mask; + writel(val, shirq->regs.base + shirq->regs.enb_reg); + spin_unlock_irqrestore(&lock, flags); +} + +static struct irq_chip shirq_chip = { + .name = "spear_shirq", + .ack = shirq_irq_mask, + .mask = shirq_irq_mask, + .unmask = shirq_irq_unmask, +}; + +static void shirq_handler(unsigned irq, struct irq_desc *desc) +{ + u32 i, val, mask; + struct spear_shirq *shirq = get_irq_data(irq); + + desc->chip->ack(irq); + while ((val = readl(shirq->regs.base + shirq->regs.status_reg) & + shirq->regs.status_reg_mask)) { + for (i = 0; (i < shirq->dev_count) && val; i++) { + if (!(shirq->dev_config[i].status_mask & val)) + continue; + + generic_handle_irq(shirq->dev_config[i].virq); + + /* clear interrupt */ + val &= ~shirq->dev_config[i].status_mask; + if ((shirq->regs.clear_reg == -1) || + shirq->dev_config[i].clear_mask == -1) + continue; + mask = readl(shirq->regs.base + shirq->regs.clear_reg); + if (shirq->regs.reset_to_clear) + mask &= ~shirq->dev_config[i].clear_mask; + else + mask |= shirq->dev_config[i].clear_mask; + writel(mask, shirq->regs.base + shirq->regs.clear_reg); + } + } + desc->chip->unmask(irq); +} + +int spear_shirq_register(struct spear_shirq *shirq) +{ + int i; + + if (!shirq || !shirq->dev_config || !shirq->regs.base) + return -EFAULT; + + if (!shirq->dev_count) + return -EINVAL; + + set_irq_chained_handler(shirq->irq, shirq_handler); + for (i = 0; i < shirq->dev_count; i++) { + set_irq_chip(shirq->dev_config[i].virq, &shirq_chip); + set_irq_handler(shirq->dev_config[i].virq, handle_simple_irq); + set_irq_flags(shirq->dev_config[i].virq, IRQF_VALID); + set_irq_chip_data(shirq->dev_config[i].virq, shirq); + } + + set_irq_data(shirq->irq, shirq); + return 0; +} -- cgit v1.1