[PATCH v2] drm/i915: Increase FLR timeout from 3s to 9s

[Nirmoy Das]

On 5/24/2024 1:58 AM, Andi Shyti wrote:
> Following the guidelines it takes 3 seconds to perform an FLR
> reset. Let's give it a bit more slack because this time can
> change depending on the platform and on the firmware
>
> Signed-off-by: Andi Shyti <andi.shyti at linux.intel.com>
Reviewed-by: Nirmoy Das <nirmoy.das at intel.com>
> ---
> Hi,
>
> In this second version I removed patch 2 that was ignoring the
> FLR reset timeouts, until we develop a proper patch.
>
> This first patch is basically the same as v1. Thanks Nirmoy for
> your review.
>
> Andi
>
>   drivers/gpu/drm/i915/intel_uncore.c | 9 ++++++++-
>   1 file changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/i915/intel_uncore.c b/drivers/gpu/drm/i915/intel_uncore.c
> index 729409a4bada..2eba289d88ad 100644
> --- a/drivers/gpu/drm/i915/intel_uncore.c
> +++ b/drivers/gpu/drm/i915/intel_uncore.c
> @@ -2614,11 +2614,18 @@ void intel_uncore_prune_engine_fw_domains(struct intel_uncore *uncore,
>   static void driver_initiated_flr(struct intel_uncore *uncore)
>   {
>   	struct drm_i915_private *i915 = uncore->i915;
> -	const unsigned int flr_timeout_ms = 3000; /* specs recommend a 3s wait */
> +	unsigned int flr_timeout_ms;
>   	int ret;
>   
>   	drm_dbg(&i915->drm, "Triggering Driver-FLR\n");
>   
> +	/*
> +	 * The specification recommends a 3 seconds FLR reset timeout. To be
> +	 * cautious, we will extend this to 9 seconds, three times the specified
> +	 * timeout.
> +	 */
> +	flr_timeout_ms = 9000;
> +
>   	/*
>   	 * Make sure any pending FLR requests have cleared by waiting for the
>   	 * FLR trigger bit to go to zero. Also clear GU_DEBUG's DRIVERFLR_STATUS