From 8bbe09ee4d2c3f201c302f0af75a7c5e17d72625 Mon Sep 17 00:00:00 2001 From: Archit Taneja Date: Mon, 10 Sep 2012 17:31:39 +0530 Subject: [PATCH] OMAPDSS: DISPC: Configure writeback FIFOs Extend the DISPC fifo functions to also configure the writeback FIFO thresholds. The most optimal configuration for writeback is to push out data to the interconnect the moment writeback pushes enough pixels in the FIFO to form a burst. This reduces the chance of writeback overflowing it's FIFO. Signed-off-by: Archit Taneja --- drivers/video/omap2/dss/dispc.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/drivers/video/omap2/dss/dispc.c b/drivers/video/omap2/dss/dispc.c index 9f083a952747..6f326765f341 100644 --- a/drivers/video/omap2/dss/dispc.c +++ b/drivers/video/omap2/dss/dispc.c @@ -993,7 +993,7 @@ void dispc_wb_set_channel_in(enum dss_writeback_channel channel) static void dispc_ovl_set_burst_size(enum omap_plane plane, enum omap_burst_size burst_size) { - static const unsigned shifts[] = { 6, 14, 14, 14, }; + static const unsigned shifts[] = { 6, 14, 14, 14, 14, }; int shift; shift = shifts[plane]; @@ -1225,6 +1225,14 @@ void dispc_ovl_compute_fifo_thresholds(enum omap_plane plane, if (manual_update && dss_has_feature(FEAT_OMAP3_DSI_FIFO_BUG)) { *fifo_low = ovl_fifo_size - burst_size * 2; *fifo_high = total_fifo_size - burst_size; + } else if (plane == OMAP_DSS_WB) { + /* + * Most optimal configuration for writeback is to push out data + * to the interconnect the moment writeback pushes enough pixels + * in the FIFO to form a burst + */ + *fifo_low = 0; + *fifo_high = burst_size; } else { *fifo_low = ovl_fifo_size - burst_size; *fifo_high = total_fifo_size - buf_unit; -- 2.39.5