From 7d045170ac1bf512ed148e97432b7a8d772943e9 Mon Sep 17 00:00:00 2001 From: Martin Pietryka Date: Wed, 27 Apr 2016 21:39:15 +0200 Subject: drivers/video/am335x-fb: Add support for 16bpp format 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 Linux 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 Reviewed-by: Hannes Schmelzer Tested-by: Hannes Schmelzer --- drivers/video/am335x-fb.c | 22 +++++++++++++++++++--- 1 file changed, 19 insertions(+), 3 deletions(-) (limited to 'drivers/video') diff --git a/drivers/video/am335x-fb.c b/drivers/video/am335x-fb.c index 0ec843f6b3..d984435ea4 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; -- cgit v1.2.1 From 3d47b2d741683023de05f08f9adb4bd25c189c46 Mon Sep 17 00:00:00 2001 From: Martin Pietryka Date: Wed, 27 Apr 2016 21:39:16 +0200 Subject: drivers/video/am335x-fb: Properly point framebuffer behind palette The DMA was outputting the palette on the screen because the base for the DMA was not after the palette. In addition to that, the ceiling was also too high, this led that the output on the screen was shifted. NOTE: According to the TRM, even in 16/24bit mode a palette is required in the first 32 bytes of the framebuffer. See also: https://e2e.ti.com/support/arm/sitara_arm/f/791/p/234967/834483#834483 "In this mode, the LCDC will assume all information is data and thus you need to ensure that the DMA points to the first pixel of data and not the first entry in the frame buffer which is the beginning of the 512 byte palette." Signed-off-by: Martin Pietryka Reviewed-by: Hannes Schmelzer Tested-by: Hannes Schmelzer --- drivers/video/am335x-fb.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'drivers/video') diff --git a/drivers/video/am335x-fb.c b/drivers/video/am335x-fb.c index d984435ea4..bb5cc9788a 100644 --- a/drivers/video/am335x-fb.c +++ b/drivers/video/am335x-fb.c @@ -143,6 +143,8 @@ int am335xfb_init(struct am335x_lcdpanel *panel) /* palette default entry */ memset((void *)gd->fb_base, 0, 0x20); *(unsigned int *)gd->fb_base = 0x4000; + /* point fb behind palette */ + gd->fb_base += 0x20; /* turn ON display through powercontrol function if accessible */ if (0 != panel->panel_power_ctrl) @@ -154,9 +156,9 @@ int am335xfb_init(struct am335x_lcdpanel *panel) lcdhw->raster_ctrl = 0; lcdhw->ctrl = LCD_CLK_DIVISOR(panel->pxl_clk_div) | LCD_RASTER_MODE; lcdhw->lcddma_fb0_base = gd->fb_base; - lcdhw->lcddma_fb0_ceiling = gd->fb_base + FBSIZE(panel) + 0x20; + lcdhw->lcddma_fb0_ceiling = gd->fb_base + FBSIZE(panel); lcdhw->lcddma_fb1_base = gd->fb_base; - lcdhw->lcddma_fb1_ceiling = gd->fb_base + FBSIZE(panel) + 0x20; + lcdhw->lcddma_fb1_ceiling = gd->fb_base + FBSIZE(panel); lcdhw->lcddma_ctrl = LCD_DMA_BURST_SIZE(LCD_DMA_BURST_16); lcdhw->raster_timing0 = LCD_HORLSB(panel->hactive) | @@ -179,8 +181,6 @@ int am335xfb_init(struct am335x_lcdpanel *panel) LCD_TFT_MODE | LCD_RASTER_ENABLE; - gd->fb_base += 0x20; /* point fb behind palette */ - debug("am335x-fb: waiting picture to be stable.\n."); mdelay(panel->pon_delay); -- cgit v1.2.1