Re: [PATCH v1 4/4] ARM: tegra: Clear EMC interrupts on resume from LP1 on Tegra30+

From: Jon Hunter
Date: Mon Nov 19 2018 - 17:00:20 EST



On 30/08/2018 19:54, Dmitry Osipenko wrote:
> Two interrupts are raised on resume from LP1 on Tegra30+: first is the
> clock change completed interrupt which is set after updating timing
> configuration, second is DLL alarm interrupt which is set when DLL
> starts re-calibration after being reset. Clear these two interrupts
> in the end of exiting from the self-refresh mode for consistency, that
> will also allow to not receive spurious interrupts in the EMC driver
> after resume from suspend.
>
> Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx>
> ---
> arch/arm/mach-tegra/sleep-tegra30.S | 7 +++++++
> 1 file changed, 7 insertions(+)
>
> diff --git a/arch/arm/mach-tegra/sleep-tegra30.S b/arch/arm/mach-tegra/sleep-tegra30.S
> index 828f6c37afde..78c6e9fb56e7 100644
> --- a/arch/arm/mach-tegra/sleep-tegra30.S
> +++ b/arch/arm/mach-tegra/sleep-tegra30.S
> @@ -26,6 +26,7 @@
> #include "irammap.h"
> #include "sleep.h"
>
> +#define EMC_INTSTATUS 0x0
> #define EMC_CFG 0xc
> #define EMC_ADR_CFG 0x10
> #define EMC_TIMING_CONTROL 0x28
> @@ -44,6 +45,9 @@
> #define EMC_XM2VTTGENPADCTRL 0x310
> #define EMC_XM2VTTGENPADCTRL2 0x314
>
> +#define EMC_CLKCHANGE_COMPLETE_INT (1 << 4)
> +#define EMC_DLL_ALARM_INT (1 << 7)
> +
> #define MC_EMEM_ARB_CFG 0x90
>
> #define PMC_CTRL 0x0
> @@ -539,6 +543,9 @@ zcal_done:
>
> emc_timing_update r1, r0
>
> + mov r1, #(EMC_CLKCHANGE_COMPLETE_INT | EMC_DLL_ALARM_INT)
> + str r1, [r0, #EMC_INTSTATUS] @ clear interrupts
> +
> /* Tegra114 had dual EMC channel, now config the other one */
> cmp r10, #TEGRA114
> bne __no_dual_emc_chanl
>

Where are these interrupts enabled? I did not see where they are
enabled. I see that the Tegra24 EMC driver does poll these, but it did
not look like they were enabled. If they are enabled, I wondering if
they should be masked on entering self-refresh?

Cheers
Jon

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