karo: merge with Ka-Ro specific tree for secure boot support

[karo-tx-uboot.git] / drivers / video / mxsfb.c

diff --git a/drivers/video/mxsfb.c b/drivers/video/mxsfb.c
index f7b5827388d877f1e5abac41db6187a794d35952..68293d2b75dcc019d56ca2e98e8864ed1088759c 100644 (file)
--- a/drivers/video/mxsfb.c
+++ b/drivers/video/mxsfb.c
@@ -16,6 +16,8 @@
 #include <asm/errno.h>
 #include <asm/io.h>
 
+#include <asm/imx-common/dma.h>
+
 #include "videomodes.h"
 
 #define        PS2KHZ(ps)      (1000000000UL / (ps))
@@ -23,6 +25,18 @@
 DECLARE_GLOBAL_DATA_PTR;
 
 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:
@@ -82,6 +96,9 @@ 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);
 
@@ -121,8 +138,10 @@ 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);
@@ -185,5 +204,28 @@ void *video_hw_init(void)
        /* Start framebuffer */
        mxs_lcd_init(&panel, &mode, bpp);
 
-       return &panel;
+#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;
 }