To support 16bpp we just need to change the raster_ctrl register accordingly. Also 32bpp mode should work as well, but was not tested. According to the TRM the uppermost byte will be ignored when LCD_TFT_24BPP_UNPACK is set.
The switch logic is based on the Liunx kernel tilcdc driver: drivers/gpu/drm/tilcdc/tilcdc_crtc.c: lines 407 through 419 (kernel was checked out at commit: bcc981e9ed8)
Signed-off-by: Martin Pietryka martin.pietryka@chello.at ---
Changes in v3: - Moved switch statement before changing any registers
drivers/video/am335x-fb.c | 22 +++++++++++++++++++--- 1 file changed, 19 insertions(+), 3 deletions(-)
diff --git a/drivers/video/am335x-fb.c b/drivers/video/am335x-fb.c index 0ec843f..d984435 100644 --- a/drivers/video/am335x-fb.c +++ b/drivers/video/am335x-fb.c @@ -5,7 +5,7 @@ * minimal framebuffer driver for TI's AM335x SoC to be compatible with * Wolfgang Denk's LCD-Framework (CONFIG_LCD, common/lcd.c) * - * - supporting only 24bit RGB/TFT raster Mode (not using palette) + * - supporting 16/24/32bit RGB/TFT raster Mode (not using palette) * - sets up LCD controller as in 'am335x_lcdpanel' struct given * - starts output DMA from gd->fb_base buffer * @@ -106,6 +106,8 @@ int lcd_get_size(int *line_length)
int am335xfb_init(struct am335x_lcdpanel *panel) { + u32 raster_ctrl = 0; + if (0 == gd->fb_base) { printf("ERROR: no valid fb_base stored in GLOBAL_DATA_PTR!\n"); return -1; @@ -115,6 +117,21 @@ int am335xfb_init(struct am335x_lcdpanel *panel) return -1; }
+ /* We can already set the bits for the raster_ctrl in this check */ + switch (panel->bpp) { + case 16: + break; + case 32: + raster_ctrl |= LCD_TFT_24BPP_UNPACK; + /* fallthrough */ + case 24: + raster_ctrl |= LCD_TFT_24BPP_MODE; + break; + default: + error("am335x-fb: invalid bpp value: %d\n", panel->bpp); + return -1; + } + debug("setting up LCD-Controller for %dx%dx%d (hfp=%d,hbp=%d,hsw=%d / ", panel->hactive, panel->vactive, panel->bpp, panel->hfp, panel->hbp, panel->hsw); @@ -157,8 +174,7 @@ int am335xfb_init(struct am335x_lcdpanel *panel) LCD_HBPMSB(panel->hbp) | LCD_HFPMSB(panel->hfp) | 0x0000FF00; /* clk cycles for ac-bias */ - lcdhw->raster_ctrl = LCD_TFT_24BPP_MODE | - LCD_TFT_24BPP_UNPACK | + lcdhw->raster_ctrl = raster_ctrl | LCD_PALMODE_RAWDATA | LCD_TFT_MODE | LCD_RASTER_ENABLE;