Commit 7dd4f4df authored by Ashley Thomas's avatar Ashley Thomas Committed by Alex Deucher
Browse files

drm/amd/display: fail instead of div by zero/bugcheck 



[why]
If pbn_per_slot is 0, fail instead of dividing by zero and
bugchecking.

[how]
Check for zero divisor before division operation.

Signed-off-by: default avatarAshley Thomas <Ashley.Thomas2@amd.com>
Reviewed-by: default avatarWyatt Wood <Wyatt.Wood@amd.com>
Acked-by: default avatarQingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
parent 81e8da71

drivers/gpu/drm/amd/display/dc/core/dc_debug.c

+2 −0
Original line number Diff line number Diff line
@@ -420,6 +420,8 @@ char *dc_status_to_str(enum dc_status status) 
		return "Fail clk below required CFG (hard_min in PPLIB)";

	case DC_NOT_SUPPORTED:

		return "The operation is not supported.";

	case DC_UNSUPPORTED_VALUE:

		return "The value specified is not supported.";

	case DC_ERROR_UNEXPECTED:

		return "Unexpected error";

	}

drivers/gpu/drm/amd/display/dc/core/dc_link.c

+4 −0
Original line number Diff line number Diff line
@@ -2952,6 +2952,10 @@ enum dc_status dc_link_allocate_mst_payload(struct pipe_ctx *pipe_ctx) 


	/* slot X.Y for only current stream */

	pbn_per_slot = get_pbn_per_slot(stream);

	if (pbn_per_slot.value == 0) {

		DC_LOG_ERROR("Failure: pbn_per_slot==0 not allowed. Cannot continue, returning DC_UNSUPPORTED_VALUE.\n");

		return DC_UNSUPPORTED_VALUE;

	}

	pbn = get_pbn_from_timing(pipe_ctx);

	avg_time_slots_per_mtp = dc_fixpt_div(pbn, pbn_per_slot);

drivers/gpu/drm/amd/display/dc/inc/core_status.h

+1 −0
Original line number Diff line number Diff line
@@ -51,6 +51,7 @@ enum dc_status { 
	DC_FAIL_CLK_BELOW_CFG_REQUIRED = 23, /*THIS IS hard_min in PPLIB*/



	DC_NOT_SUPPORTED = 24,

	DC_UNSUPPORTED_VALUE = 25,



	DC_ERROR_UNEXPECTED = -1

};