From 8d8a2761521c01f70f79fdc69d8209f98ecd9458 Mon Sep 17 00:00:00 2001 From: Boris BREZILLON Date: Fri, 6 Jun 2014 14:36:11 -0700 Subject: ARM: at91: fix at91_sysirq_mask_rtc for sam9x5 SoCs commit 9dcc87fec8947308e0111c65dcd881e6aa5b1673 upstream. sam9x5 SoCs have the following errata: "RTC: Interrupt Mask Register cannot be used Interrupt Mask Register read always returns 0." Hence we should not rely on what IMR claims about already masked IRQs and just disable all IRQs. Signed-off-by: Boris BREZILLON Reported-by: Bryan Evenson Reviewed-by: Johan Hovold Acked-by: Nicolas Ferre Cc: Bryan Evenson Cc: Andrew Victor Cc: Jean-Christophe Plagniol-Villard Cc: Alessandro Zummo Cc: Mark Roszko Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Jiri Slaby --- arch/arm/mach-at91/sysirq_mask.c | 22 +++++++++++++--------- 1 file changed, 13 insertions(+), 9 deletions(-) diff --git a/arch/arm/mach-at91/sysirq_mask.c b/arch/arm/mach-at91/sysirq_mask.c index 2ba694f9626b..f8bc3511a8c8 100644 --- a/arch/arm/mach-at91/sysirq_mask.c +++ b/arch/arm/mach-at91/sysirq_mask.c @@ -25,24 +25,28 @@ #include "generic.h" -#define AT91_RTC_IDR 0x24 /* Interrupt Disable Register */ -#define AT91_RTC_IMR 0x28 /* Interrupt Mask Register */ +#define AT91_RTC_IDR 0x24 /* Interrupt Disable Register */ +#define AT91_RTC_IMR 0x28 /* Interrupt Mask Register */ +#define AT91_RTC_IRQ_MASK 0x1f /* Available IRQs mask */ void __init at91_sysirq_mask_rtc(u32 rtc_base) { void __iomem *base; - u32 mask; base = ioremap(rtc_base, 64); if (!base) return; - mask = readl_relaxed(base + AT91_RTC_IMR); - if (mask) { - pr_info("AT91: Disabling rtc irq\n"); - writel_relaxed(mask, base + AT91_RTC_IDR); - (void)readl_relaxed(base + AT91_RTC_IMR); /* flush */ - } + /* + * sam9x5 SoCs have the following errata: + * "RTC: Interrupt Mask Register cannot be used + * Interrupt Mask Register read always returns 0." + * + * Hence we're not relying on IMR values to disable + * interrupts. + */ + writel_relaxed(AT91_RTC_IRQ_MASK, base + AT91_RTC_IDR); + (void)readl_relaxed(base + AT91_RTC_IMR); /* flush */ iounmap(base); } -- cgit v1.2.3