Commit a2210d57 authored Oct 10, 2013 by Philipp Zabel Committed by Greg Kroah-Hartman Oct 11, 2013

staging: drm/imx: also allow to allocate only 2 DMFC slots for DP full plane



Connecting a 320x240 parallel display on i.MX6 resulted in an invalid DRDY
signal because the DC would not receive NL/EOL events on every line.
Reducing the allocated DMFC space from 4 slots (256 * 128-bit) to 2 slots
(128 * 128-bit) solved the problem.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent c35d6a37

drivers/staging/imx-drm/ipu-v3/ipu-dmfc.c

+4 −4

Original line number	Diff line number	Diff line
		@@ -307,13 +307,13 @@ int ipu_dmfc_alloc_bandwidth(struct dmfc_channel *dmfc,
		goto out;
		}

		/* Always allocate at least 1284 bytes (2 slots) /
		if (slots < 2)
		slots = 2;

		/* For the MEM_BG channel, first try to allocate twice the slots */
		if (dmfc->data->ipu_channel == IPUV3_CHANNEL_MEM_BG_SYNC)
		segment = dmfc_find_slots(priv, slots * 2);
		else if (slots < 2)
		/* Always allocate at least 1284 bytes (2 slots) /
		slots = 2;

		if (segment >= 0)
		slots *= 2;
		else