Re: [PATCH 1/1] mmc: sunxi: Disable irq during pm_suspend

From: Marc Zyngier
Date: Tue Jul 03 2018 - 08:01:59 EST


On 03/07/18 08:28, Stefan Mavrodiev wrote:
> When mmc host controller enters suspend state, the clocks are
> disabled, but irqs are not. For some reason the irqchip emmits

Not so much the irqchip, but the device itself.

> false interrupts, which causes system lock loop.

I'm not sure the interrupts are fake. They are indicative of some state
of the HW...

>
> Debug log is:
> ...
> sunxi-mmc 1c11000.mmc: setting clk to 52000000, rounded 51200000
> sunxi-mmc 1c11000.mmc: enabling the clock
> sunxi-mmc 1c11000.mmc: cmd 13(8000014d) arg 10000 ie 0x0000bbc6 len 0
> sunxi-mmc 1c11000.mmc: irq: rq (ptrval) mi 00000004 idi 00000000
> sunxi-mmc 1c11000.mmc: cmd 6(80000146) arg 3210101 ie 0x0000bbc6 len 0
> sunxi-mmc 1c11000.mmc: irq: rq (ptrval) mi 00000004 idi 00000000
> sunxi-mmc 1c11000.mmc: cmd 13(8000014d) arg 10000 ie 0x0000bbc6 len 0
> sunxi-mmc 1c11000.mmc: irq: rq (ptrval) mi 00000004 idi 00000000
> mmc1: new DDR MMC card at address 0001
> mmcblk1: mmc1:0001 AGND3R 14.6 GiB
> mmcblk1boot0: mmc1:0001 AGND3R partition 1 4.00 MiB
> mmcblk1boot1: mmc1:0001 AGND3R partition 2 4.00 MiB
> sunxi-mmc 1c11000.mmc: cmd 18(80003352) arg 0 ie 0x0000fbc2 len 409
> sunxi-mmc 1c11000.mmc: irq: rq (ptrval) mi 00004000 idi 00000002
> mmcblk1: p1
> sunxi-mmc 1c11000.mmc: irq: rq (null) mi 00000000 idi 00000000
> sunxi-mmc 1c11000.mmc: irq: rq (null) mi 00000000 idi 00000000
> sunxi-mmc 1c11000.mmc: irq: rq (null) mi 00000000 idi 00000000
> sunxi-mmc 1c11000.mmc: irq: rq (null) mi 00000000 idi 00000000
> and so on...

The clock is off, and yet the thing manages to generate interrupts. Great...

>
> This issue apears on eMMC cards, routed on MMC2 slot. The patch is
> tested with A20-OLinuXino-MICRO/LIME/LIME2 boards.
>
> Fixes: 9a8e1e8cc2c0 ("mmc: sunxi: Add runtime_pm support")
> Signed-off-by: Stefan Mavrodiev <stefan@xxxxxxxxxx>
> ---
> drivers/mmc/host/sunxi-mmc.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/drivers/mmc/host/sunxi-mmc.c b/drivers/mmc/host/sunxi-mmc.c
> index e747259..acae7a8 100644
> --- a/drivers/mmc/host/sunxi-mmc.c
> +++ b/drivers/mmc/host/sunxi-mmc.c
> @@ -1446,6 +1446,7 @@ static int sunxi_mmc_runtime_resume(struct device *dev)
> sunxi_mmc_init_host(host);
> sunxi_mmc_set_bus_width(host, mmc->ios.bus_width);
> sunxi_mmc_set_clk(host, &mmc->ios);
> + enable_irq(host->irq);
>
> return 0;
> }
> @@ -1455,6 +1456,7 @@ static int sunxi_mmc_runtime_suspend(struct device *dev)
> struct mmc_host *mmc = dev_get_drvdata(dev);
> struct sunxi_mmc_host *host = mmc_priv(mmc);
>
> + disable_irq(host->irq);
> sunxi_mmc_reset_host(host);
> sunxi_mmc_disable(host);
>
>

For the record, this patch fixes the boot issues I've observed on my
cubietruck.

Acked-by: Marc Zyngier <marc.zyngier@xxxxxxx>
Tested-by: Marc Zyngier <marc.zyngier@xxxxxxx>

M.
--
Jazz is not dead. It just smells funny...