Re: [PATCH v3 3/6] clocksource: exynos_mct: Refactor resources allocation

From: Krzysztof Kozlowski
Date: Wed Oct 17 2018 - 10:29:32 EST


On Wed, 17 Oct 2018 at 15:42, Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> wrote:
>
> Move interrupts allocation from exynos4_timer_resources() into separate
> function together with the interrupt number parsing code from
> mct_init_dt(), so the code for managing interrupts is kept together.
> While touching exynos4_timer_resources() function, move of_iomap() to it.
> No functional changes.
>
> Signed-off-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
> ---
> drivers/clocksource/exynos_mct.c | 49 +++++++++++++++++++-------------
> 1 file changed, 30 insertions(+), 19 deletions(-)
>
> diff --git a/drivers/clocksource/exynos_mct.c b/drivers/clocksource/exynos_mct.c
> index 49413900b24c..02ad55db390b 100644
> --- a/drivers/clocksource/exynos_mct.c
> +++ b/drivers/clocksource/exynos_mct.c
> @@ -502,11 +502,14 @@ static int exynos4_mct_dying_cpu(unsigned int cpu)
> return 0;
> }
>
> -static int __init exynos4_timer_resources(struct device_node *np, void __iomem *base)
> +static int __init exynos4_timer_resources(struct device_node *np)
> {
> - int err, cpu;
> struct clk *mct_clk, *tick_clk;
>
> + reg_base = of_iomap(np, 0);
> + if (!reg_base)
> + panic("%s: unable to ioremap mct address space\n", __func__);
> +
> tick_clk = of_clk_get_by_name(np, "fin_pll");
> if (IS_ERR(tick_clk))
> panic("%s: unable to determine tick clock rate\n", __func__);
> @@ -517,9 +520,27 @@ static int __init exynos4_timer_resources(struct device_node *np, void __iomem *
> panic("%s: unable to retrieve mct clock instance\n", __func__);
> clk_prepare_enable(mct_clk);
>
> - reg_base = base;
> - if (!reg_base)
> - panic("%s: unable to ioremap mct address space\n", __func__);
> + return 0;
> +}
> +
> +static int __init exynos4_timer_interrupts(struct device_node *np,
> + unsigned int int_type)
> +{
> + int i, err, cpu;
> +
> + mct_int_type = int_type;

This does not look good. Before, assignment was done before call to
exynos4_timer_resources(). Now, if I follow the path correctly, it
will be after. Therefore the exynos4_timer_resources() will use wrong
value. This should pop up during tests.

Best regards,
Krzysztof

> +
> + /* This driver uses only one global timer interrupt */
> + mct_irqs[MCT_G0_IRQ] = irq_of_parse_and_map(np, MCT_G0_IRQ);
> +
> + /*
> + * Find out the number of local irqs specified. The local
> + * timer irqs are specified after the four global timer
> + * irqs are specified.
> + */
> + nr_irqs = of_irq_count(np);
> + for (i = MCT_L0_IRQ; i < nr_irqs; i++)
> + mct_irqs[i] = irq_of_parse_and_map(np, i);
>
> if (mct_int_type == MCT_INT_PPI) {
>
> @@ -579,24 +600,14 @@ static int __init exynos4_timer_resources(struct device_node *np, void __iomem *
>
> static int __init mct_init_dt(struct device_node *np, unsigned int int_type)
> {
> - u32 nr_irqs, i;
> int ret;
>
> - mct_int_type = int_type;
> -
> - /* This driver uses only one global timer interrupt */
> - mct_irqs[MCT_G0_IRQ] = irq_of_parse_and_map(np, MCT_G0_IRQ);
> + ret = exynos4_timer_resources(np);
> + if (ret)
> + return ret;
>
> - /*
> - * Find out the number of local irqs specified. The local
> - * timer irqs are specified after the four global timer
> - * irqs are specified.
> - */
> - nr_irqs = of_irq_count(np);
> - for (i = MCT_L0_IRQ; i < nr_irqs; i++)
> - mct_irqs[i] = irq_of_parse_and_map(np, i);
>
> - ret = exynos4_timer_resources(np, of_iomap(np, 0));
> + ret = exynos4_timer_interrupts(np, int_type);
> if (ret)
> return ret;
>
> --
> 2.17.1
>