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path: root/drivers/video/mxsfb.c
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Diffstat (limited to 'drivers/video/mxsfb.c')
-rw-r--r--drivers/video/mxsfb.c45
1 files changed, 44 insertions, 1 deletions
diff --git a/drivers/video/mxsfb.c b/drivers/video/mxsfb.c
index 6bf9fc5..03b0f88 100644
--- a/drivers/video/mxsfb.c
+++ b/drivers/video/mxsfb.c
@@ -15,11 +15,25 @@
#include <asm/errno.h>
#include <asm/io.h>
+#include <asm/imx-common/dma.h>
+
#include "videomodes.h"
#define PS2KHZ(ps) (1000000000UL / (ps))
static GraphicDevice panel;
+struct mxs_dma_desc desc;
+
+/**
+ * mxsfb_system_setup() - Fine-tune LCDIF configuration
+ *
+ * This function is used to adjust the LCDIF configuration. This is usually
+ * needed when driving the controller in System-Mode to operate an 8080 or
+ * 6800 connected SmartLCD.
+ */
+__weak void mxsfb_system_setup(void)
+{
+}
/*
* DENX M28EVK:
@@ -75,6 +89,9 @@ static void mxs_lcd_init(GraphicDevice *panel,
writel(valid_data << LCDIF_CTRL1_BYTE_PACKING_FORMAT_OFFSET,
&regs->hw_lcdif_ctrl1);
+
+ mxsfb_system_setup();
+
writel((mode->yres << LCDIF_TRANSFER_COUNT_V_COUNT_OFFSET) | mode->xres,
&regs->hw_lcdif_transfer_count);
@@ -102,8 +119,10 @@ static void mxs_lcd_init(GraphicDevice *panel,
/* Flush FIFO first */
writel(LCDIF_CTRL1_FIFO_CLEAR, &regs->hw_lcdif_ctrl1_set);
+#ifndef CONFIG_VIDEO_MXS_MODE_SYSTEM
/* Sync signals ON */
setbits_le32(&regs->hw_lcdif_vdctrl4, LCDIF_VDCTRL4_SYNC_SIGNALS_ON);
+#endif
/* FIFO cleared */
writel(LCDIF_CTRL1_FIFO_CLEAR, &regs->hw_lcdif_ctrl1_clr);
@@ -161,7 +180,8 @@ void *video_hw_init(void)
panel.memSize = mode.xres * mode.yres * panel.gdfBytesPP;
/* Allocate framebuffer */
- fb = malloc(panel.memSize);
+ fb = memalign(ARCH_DMA_MINALIGN,
+ roundup(panel.memSize, ARCH_DMA_MINALIGN));
if (!fb) {
printf("MXSFB: Error allocating framebuffer!\n");
return NULL;
@@ -177,5 +197,28 @@ void *video_hw_init(void)
/* Start framebuffer */
mxs_lcd_init(&panel, &mode, bpp);
+#ifdef CONFIG_VIDEO_MXS_MODE_SYSTEM
+ /*
+ * If the LCD runs in system mode, the LCD refresh has to be triggered
+ * manually by setting the RUN bit in HW_LCDIF_CTRL register. To avoid
+ * having to set this bit manually after every single change in the
+ * framebuffer memory, we set up specially crafted circular DMA, which
+ * sets the RUN bit, then waits until it gets cleared and repeats this
+ * infinitelly. This way, we get smooth continuous updates of the LCD.
+ */
+ struct mxs_lcdif_regs *regs = (struct mxs_lcdif_regs *)MXS_LCDIF_BASE;
+
+ memset(&desc, 0, sizeof(struct mxs_dma_desc));
+ desc.address = (dma_addr_t)&desc;
+ desc.cmd.data = MXS_DMA_DESC_COMMAND_NO_DMAXFER | MXS_DMA_DESC_CHAIN |
+ MXS_DMA_DESC_WAIT4END |
+ (1 << MXS_DMA_DESC_PIO_WORDS_OFFSET);
+ desc.cmd.pio_words[0] = readl(&regs->hw_lcdif_ctrl) | LCDIF_CTRL_RUN;
+ desc.cmd.next = (uint32_t)&desc.cmd;
+
+ /* Execute the DMA chain. */
+ mxs_dma_circ_start(MXS_DMA_CHANNEL_AHB_APBH_LCDIF, &desc);
+#endif
+
return (void *)&panel;
}