dect
/
linux-2.6
Archived
13
0
Fork 0
Code Releases Activity

OMAPDSS: DISPC: Add naive threshold calc for fifomerge 

Take fifo merge into use by implementing a rather naive fifo merge
threshold calculation: keep the low threshold always the same, but
increase the high threshold when fifo merge is used.

This should greatly increase the time between pixel data fetches from
SDRAM, as the usable fifo size is much larger. However, it probably
won't help for fifo underflows, as the low threshols is kept the same.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
This commit is contained in:
Tomi Valkeinen 2012-01-13 13:18:11 +02:00
parent 83fa2f2e94
commit e0e405b925
3 changed files with 30 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

28
drivers/video/omap2/dss/dispc.c
View File

@ -1072,13 +1072,33 @@ void dispc_ovl_compute_fifo_thresholds(enum omap_plane plane,
*/
unsigned buf_unit = dss_feat_get_buffer_size_unit();
unsigned fifo_size, burst_size;
unsigned ovl_fifo_size, total_fifo_size, burst_size;
int i;
burst_size = dispc_ovl_get_burst_size(plane);
fifo_size = dispc_ovl_get_fifo_size(plane);
ovl_fifo_size = dispc_ovl_get_fifo_size(plane);
*fifo_low = fifo_size - burst_size;
*fifo_high = fifo_size - buf_unit;
if (use_fifomerge) {
total_fifo_size = 0;
for (i = 0; i < omap_dss_get_num_overlays(); ++i)
total_fifo_size += dispc_ovl_get_fifo_size(i);
} else {
total_fifo_size = ovl_fifo_size;
}
/*
* We use the same low threshold for both fifomerge and non-fifomerge
* cases, but for fifomerge we calculate the high threshold using the
* combined fifo size
*/
if (dss_has_feature(FEAT_OMAP3_DSI_FIFO_BUG)) {
*fifo_low = ovl_fifo_size - burst_size * 2;
*fifo_high = total_fifo_size - burst_size;
} else {
*fifo_low = ovl_fifo_size - burst_size;
*fifo_high = total_fifo_size - buf_unit;
}
}
static void dispc_ovl_set_fir(enum omap_plane plane,

6
drivers/video/omap2/dss/dss_features.c
View File

@ -370,7 +370,8 @@ static const struct omap_dss_features omap3430_dss_features = {
FEAT_LINEBUFFERSPLIT | FEAT_RESIZECONF |
FEAT_DSI_PLL_FREQSEL | FEAT_DSI_REVERSE_TXCLKESC |
FEAT_VENC_REQUIRES_TV_DAC_CLK | FEAT_CPR | FEAT_PRELOAD |
FEAT_FIR_COEF_V | FEAT_ALPHA_FIXED_ZORDER | FEAT_FIFO_MERGE,
FEAT_FIR_COEF_V | FEAT_ALPHA_FIXED_ZORDER | FEAT_FIFO_MERGE |
FEAT_OMAP3_DSI_FIFO_BUG,
.num_mgrs = 2,
.num_ovls = 3,
@ -394,7 +395,8 @@ static const struct omap_dss_features omap3630_dss_features = {
FEAT_ROWREPEATENABLE | FEAT_LINEBUFFERSPLIT |
FEAT_RESIZECONF | FEAT_DSI_PLL_PWR_BUG |
FEAT_DSI_PLL_FREQSEL | FEAT_CPR | FEAT_PRELOAD |
FEAT_FIR_COEF_V | FEAT_ALPHA_FIXED_ZORDER | FEAT_FIFO_MERGE,
FEAT_FIR_COEF_V | FEAT_ALPHA_FIXED_ZORDER | FEAT_FIFO_MERGE |
FEAT_OMAP3_DSI_FIFO_BUG,
.num_mgrs = 2,
.num_ovls = 3,

2
drivers/video/omap2/dss/dss_features.h
View File

@ -59,6 +59,8 @@ enum dss_feat_id {
FEAT_ALPHA_FIXED_ZORDER = 1 << 26,
FEAT_ALPHA_FREE_ZORDER = 1 << 27,
FEAT_FIFO_MERGE = 1 << 28,
/* An unknown HW bug causing the normal FIFO thresholds not to work */
FEAT_OMAP3_DSI_FIFO_BUG = 1 << 29,
};
/* DSS register field id */