Hi,
On Wed, Jun 10, 2015 at 10:10 PM, Javier Martinez Canillas
<javier.marti...@collabora.co.uk> wrote:
> The Exynos interrupt combiner IP looses its state when the SoC enters
> into a low power state during a Suspend-to-RAM. This means that if a
> IRQ is used as a source, the interrupts for the devices are disabled
> when the system is resumed from a sleep state so are not triggered.
>
> Save the interrupt enable set register for each combiner group and
> restore it after resume to make sure that the interrupts are enabled.
>
> Signed-off-by: Javier Martinez Canillas <javier.marti...@collabora.co.uk>
> ---
>
> Hello,
>
> I noticed this issue because after a S2R, IRQs for some devices didn't
> trigger anymore but others continued working and all of them had lines
> from a GPIO chip as their interrupt source.
>
> The only difference was that the GPIO pins that were not working after
> a resume, were the ones that had the interrupt combiner as interrupt
> parent.
>
> With this patch now all perhiperals are working correctly after a resume.
> Tested on an Exynos5250 Snow, Exynos5420 Peach Pit and Exynos5800 Peach Pi
> Chromebooks.
>
> Best regards,
> Javier
>
> drivers/irqchip/exynos-combiner.c | 61
> +++++++++++++++++++++++++++++++++++----
> 1 file changed, 56 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/irqchip/exynos-combiner.c
> b/drivers/irqchip/exynos-combiner.c
> index 5945223b73fa..69c710641bfa 100644
> --- a/drivers/irqchip/exynos-combiner.c
> +++ b/drivers/irqchip/exynos-combiner.c
> @@ -13,6 +13,7 @@
> #include <linux/init.h>
> #include <linux/io.h>
> #include <linux/slab.h>
> +#include <linux/syscore_ops.h>
> #include <linux/irqdomain.h>
> #include <linux/irqchip/chained_irq.h>
> #include <linux/interrupt.h>
> @@ -34,9 +35,14 @@ struct combiner_chip_data {
> unsigned int irq_mask;
> void __iomem *base;
> unsigned int parent_irq;
> +#ifdef CONFIG_PM
> + u32 pm_save;
> +#endif
> };
>
> +static struct combiner_chip_data *combiner_data;
> static struct irq_domain *combiner_irq_domain;
> +static unsigned int max_nr = 20;
>
> static inline void __iomem *combiner_base(struct irq_data *data)
> {
> @@ -170,12 +176,10 @@ static struct irq_domain_ops combiner_irq_domain_ops = {
> };
>
> static void __init combiner_init(void __iomem *combiner_base,
> - struct device_node *np,
> - unsigned int max_nr)
> + struct device_node *np)
> {
> int i, irq;
> unsigned int nr_irq;
> - struct combiner_chip_data *combiner_data;
>
> nr_irq = max_nr * IRQ_IN_COMBINER;
>
> @@ -201,11 +205,56 @@ static void __init combiner_init(void __iomem
> *combiner_base,
> }
> }
>
> +#ifdef CONFIG_PM
> +
> +/**
> + * combiner_suspend - save interrupt combiner state before suspend
> + *
> + * Save the interrupt enable set register for all combiner groups since
> + * the state is lost when the system enters into a sleep state.
> + *
> + */
> +static int combiner_suspend(void)
> +{
> + int i;
> +
> + for (i = 0; i < max_nr; i++)
> + combiner_data[i].pm_save =
> + __raw_readl(combiner_data[i].base +
> COMBINER_ENABLE_SET);
> +
> + return 0;
> +}
> +
> +/**
> + * combiner_resume - restore interrupt combiner state after resume
> + *
> + * Restore the interrupt enable set register for all combiner groups since
> + * the state is lost when the system enters into a sleep state on suspend.
> + *
> + */
> +static void combiner_resume(void)
> +{
> + int i;
> +
> + for (i = 0; i < max_nr; i++)
Don't you need to clear masking bits of the COMBINER_ENABLE_CLEAR
before enabling the bits?
> + __raw_writel(combiner_data[i].pm_save,
> + combiner_data[i].base + COMBINER_ENABLE_SET);
> +}
> +
> +#else
> +#define combiner_suspend NULL
> +#define combiner_resume NULL
> +#endif
> +
> +static struct syscore_ops combiner_syscore_ops = {
> + .suspend = combiner_suspend,
> + .resume = combiner_resume,
> +};
> +
> static int __init combiner_of_init(struct device_node *np,
> struct device_node *parent)
> {
> void __iomem *combiner_base;
> - unsigned int max_nr = 20;
>
> combiner_base = of_iomap(np, 0);
> if (!combiner_base) {
> @@ -219,7 +268,9 @@ static int __init combiner_of_init(struct device_node *np,
> __func__, max_nr);
> }
>
> - combiner_init(combiner_base, np, max_nr);
> + combiner_init(combiner_base, np);
> +
> + register_syscore_ops(&combiner_syscore_ops);
>
> return 0;
> }
> --
> 2.1.4
>
> --
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--
Best Regards,
Chanho Park
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