path: root/drivers/video/omap2/dss/manager.c
diff options
authorTomi Valkeinen <tomi.valkeinen@ti.com>2011-06-21 09:35:36 +0300
committerTomi Valkeinen <tomi.valkeinen@ti.com>2011-07-01 12:07:14 +0300
commit5ed8cf5b8e053832a3d0552e0a9681a3ff0325ee (patch)
tree7b344de5b36f8720cc03a762c28931b6126b212f /drivers/video/omap2/dss/manager.c
parent15ffa1dac53820bb712851d329ba465f74b00f76 (diff)
OMAP: DSS2: Fix FIFO threshold and burst size for OMAP4
The DMA FIFO threshold registers and burst size registers have changed for OMAP4. The current code only handles OMAP2/3 case, and so the values are a bit off for OMAP4. A summary of the differences between OMAP2/3 and OMAP4: Burst size: OMAP2/3: 4 x 32 bits / 8 x 32 bits / 16 x 32 bits OMAP4: 2 x 128 bits / 4 x 128 bits / 8 x 128 bits Threshold size: OMAP2/3: in bytes (8 bit units) OMAP4: in 128bit units This patch fixes the issue by creating two new helper functions in dss_features: dss_feat_get_buffer_size_unit() and dss_feat_get_burst_size_unit(). These return (in bytes) the unit size for threshold registers and unit size for burst size register, respectively, and are used to calculate correct values. For the threshold size the usage is straightforward. However, the burst size register has different multipliers for OMAP2/3 and OMAP4. This patch solves the problem by defining the multipliers for the burst size as 2x, 4x and 8x, which fit fine for the OMAP4 burst size definition (i.e. burst size unit for OMAP4 is 128bits), but requires a slight twist on OMAP2/3 by defining the burst size unit as 64bit. As the driver in practice always uses the maximum burst size, and no use case currently exists where we would want to use a smaller burst size, this patch changes the driver to hardcode the burst size when initializing DISPC. This makes the threshold configuration code somewhat simpler. Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Diffstat (limited to 'drivers/video/omap2/dss/manager.c')
1 files changed, 6 insertions, 6 deletions
diff --git a/drivers/video/omap2/dss/manager.c b/drivers/video/omap2/dss/manager.c
index 7ebaa40d3b56..49c0d77a5f24 100644
--- a/drivers/video/omap2/dss/manager.c
+++ b/drivers/video/omap2/dss/manager.c
@@ -507,7 +507,6 @@ struct overlay_cache_data {
bool replication;
bool ilace;
- enum omap_burst_size burst_size;
u32 fifo_low;
u32 fifo_high;
@@ -947,8 +946,7 @@ static int configure_overlay(enum omap_plane plane)
dispc_enable_replication(plane, c->replication);
- dispc_set_burst_size(plane, c->burst_size);
- dispc_setup_plane_fifo(plane, c->fifo_low, c->fifo_high);
+ dispc_set_fifo_threshold(plane, c->fifo_low, c->fifo_high);
dispc_enable_plane(plane, 1);
@@ -1417,7 +1415,7 @@ static int omap_dss_mgr_apply(struct omap_overlay_manager *mgr)
/* Configure overlay fifos */
for (i = 0; i < omap_dss_get_num_overlays(); ++i) {
struct omap_dss_device *dssdev;
- u32 size;
+ u32 size, burst_size;
ovl = omap_dss_get_overlay(i);
@@ -1435,6 +1433,8 @@ static int omap_dss_mgr_apply(struct omap_overlay_manager *mgr)
if (use_fifomerge)
size *= 3;
+ burst_size = dispc_get_burst_size(ovl->id);
switch (dssdev->type) {
@@ -1442,13 +1442,13 @@ static int omap_dss_mgr_apply(struct omap_overlay_manager *mgr)
default_get_overlay_fifo_thresholds(ovl->id, size,
- &oc->burst_size, &oc->fifo_low,
+ burst_size, &oc->fifo_low,
dsi_get_overlay_fifo_thresholds(ovl->id, size,
- &oc->burst_size, &oc->fifo_low,
+ burst_size, &oc->fifo_low,

Privacy Policy