From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751252Ab3GFOfh (ORCPT ); Sat, 6 Jul 2013 10:35:37 -0400 Received: from mail-pb0-f51.google.com ([209.85.160.51]:52638 "EHLO mail-pb0-f51.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750723Ab3GFOff (ORCPT ); Sat, 6 Jul 2013 10:35:35 -0400 Message-ID: <1373121329.13289.2.camel@phoenix> Subject: [PATCH RFT] irqchip: sun4i: Remove wrong irq_ack callback implementation From: Axel Lin To: Thomas Gleixner Cc: Maxime Ripard , linux-kernel@vger.kernel.org Date: Sat, 06 Jul 2013 22:35:29 +0800 Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.6.4-0ubuntu1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org According to the datasheet[1], the Interrupt IRQ Pending Registers are read-only. The implementation of sun4i_irq_ack() looks wrong because it writes to these read-only registers. This patch removes the wrong irq_ack callback implementation and all the code writing to these read-only registers in sun4i_of_init(). [1] http://dl.linux-sunxi.org/A10/A10%20User%20Manual%20-%20v1.20%20%282012-04-09%2c%20DECRYPTED%29.pdf Signed-off-by: Axel Lin --- Hi Maxime, I don't have this hardware, I'd appreciate if you can test this patch. If this patch works, I think we can just drop the patch I sent yesterday. ( It's "irqchip: sun4i: Staticize sun4i_irq_ack()" https://lkml.org/lkml/2013/7/5/43 ) Thanks, Axel drivers/irqchip/irq-sun4i.c | 18 ------------------ 1 file changed, 18 deletions(-) diff --git a/drivers/irqchip/irq-sun4i.c b/drivers/irqchip/irq-sun4i.c index b66d4ae..29b75c0a 100644 --- a/drivers/irqchip/irq-sun4i.c +++ b/drivers/irqchip/irq-sun4i.c @@ -38,18 +38,6 @@ static struct irq_domain *sun4i_irq_domain; static asmlinkage void __exception_irq_entry sun4i_handle_irq(struct pt_regs *regs); -void sun4i_irq_ack(struct irq_data *irqd) -{ - unsigned int irq = irqd_to_hwirq(irqd); - unsigned int irq_off = irq % 32; - int reg = irq / 32; - u32 val; - - val = readl(sun4i_irq_base + SUN4I_IRQ_PENDING_REG(reg)); - writel(val | (1 << irq_off), - sun4i_irq_base + SUN4I_IRQ_PENDING_REG(reg)); -} - static void sun4i_irq_mask(struct irq_data *irqd) { unsigned int irq = irqd_to_hwirq(irqd); @@ -76,7 +64,6 @@ static void sun4i_irq_unmask(struct irq_data *irqd) static struct irq_chip sun4i_irq_chip = { .name = "sun4i_irq", - .irq_ack = sun4i_irq_ack, .irq_mask = sun4i_irq_mask, .irq_unmask = sun4i_irq_unmask, }; @@ -114,11 +101,6 @@ static int __init sun4i_of_init(struct device_node *node, writel(0, sun4i_irq_base + SUN4I_IRQ_MASK_REG(1)); writel(0, sun4i_irq_base + SUN4I_IRQ_MASK_REG(2)); - /* Clear all the pending interrupts */ - writel(0xffffffff, sun4i_irq_base + SUN4I_IRQ_PENDING_REG(0)); - writel(0xffffffff, sun4i_irq_base + SUN4I_IRQ_PENDING_REG(1)); - writel(0xffffffff, sun4i_irq_base + SUN4I_IRQ_PENDING_REG(2)); - /* Enable protection mode */ writel(0x01, sun4i_irq_base + SUN4I_IRQ_PROTECTION_REG); -- 1.8.1.2