Re: [RFC PATCH v3 2/2] clk: exynos5420: Make sure MDMA0 clock is enabled during suspend

[Tomasz Figa]

2015-04-07 16:11 GMT+02:00 Javier Martinez Canillas
<javier.martinez@xxxxxxxxxxxxxxx>:
> From 78aa551ebcb9a4a7ae9d5581c33e0c0f19fe5ad6 Mon Sep 17 00:00:00 2001
> From: Javier Martinez Canillas <javier.martinez@xxxxxxxxxxxxxxx>
> Date: Tue, 7 Apr 2015 15:53:27 +0200
> Subject: [RFC PATCH] clk: exynos5420: Restore GATE_BUS_TOP on suspend
>
> Commit ae43b3289186 ("ARM: 8202/1: dmaengine: pl330: Add runtime Power
> Management support v12") added pm support for the pl330 dma driver but
> it makes the clock for the Exynos5420 MDMA0 DMA controller to be gated
> during suspend and this in turn makes its parent clock aclk266_g2d to
> be gated. But the clock needs to be ungated prior suspend to allow the
> system to be suspend and resumed correctly.
>
> Add GATE_BUS_TOP register to the list of registers to be restored when
> the system enters into a suspend state so aclk266_g2d will be ungated.
>
> Thanks to Abhilash Kesavan for figuring out that this was the issue.
>
> Fixes: ae43b32 ("ARM: 8202/1: dmaengine: pl330: Add runtime Power Management support v12")
> Signed-off-by: Javier Martinez Canillas <javier.martinez@xxxxxxxxxxxxxxx>
> ---
>  drivers/clk/samsung/clk-exynos5420.c | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/drivers/clk/samsung/clk-exynos5420.c b/drivers/clk/samsung/clk-exynos5420.c
> index 07d666cc6a29..bea4a173eef5 100644
> --- a/drivers/clk/samsung/clk-exynos5420.c
> +++ b/drivers/clk/samsung/clk-exynos5420.c
> @@ -271,6 +271,7 @@ static const struct samsung_clk_reg_dump exynos5420_set_clksrc[] = {
>         { .offset = SRC_MASK_PERIC0,            .value = 0x11111110, },
>         { .offset = SRC_MASK_PERIC1,            .value = 0x11111100, },
>         { .offset = SRC_MASK_ISP,               .value = 0x11111000, },
> +       { .offset = GATE_BUS_TOP,               .value = 0xffffffff, },
>         { .offset = GATE_BUS_DISP1,             .value = 0xffffffff, },
>         { .offset = GATE_IP_PERIC,              .value = 0xffffffff, },
>  };
> --
> 2.1.4

Looks good to me. You can consider this Acked-by, as long as Sylwester
is not opposed to this approach.

Best regards,
Tomasz
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