[ARM] pxafb: add support for FBIOPAN_DISPLAY by dma braching

dma branching is enabled by extending the current setup_frame_dma()
function to allow a 2nd set of frame/palette dma descriptors to be
used.

As a result, pxafb_dma_buff.dma_desc[], pxafb_dma_buff.pal_desc[]
and pxafb_info.fdadr[] are doubled.

This allows maximum re-use of the current dma setup code, although
the pxafb_info.fdadr[xx] for FBRx register values looks a bit odd.
Signed-off-by: Eric Miao <eric.miao@marvell.com>
Signed-off-by: Eric Miao <ycmiao@ycmiao-hp520.(none)>

arch/arm/mach-pxa/include/mach/regs-lcd.h

@@ -12,13 +12,19 @@
 #define LCCR3		(0x00C)	/* LCD Controller Control Register 3 */
 #define LCCR4		(0x010)	/* LCD Controller Control Register 4 */
 #define LCCR5		(0x014)	/* LCD Controller Control Register 5 */
-#define DFBR0		(0x020)	/* DMA Channel 0 Frame Branch Register */
-#define DFBR1		(0x024)	/* DMA Channel 1 Frame Branch Register */
 #define LCSR		(0x038)	/* LCD Controller Status Register */
 #define LIIDR		(0x03C)	/* LCD Controller Interrupt ID Register */
 #define TMEDRGBR	(0x040)	/* TMED RGB Seed Register */
 #define TMEDCR		(0x044)	/* TMED Control Register */
 
+#define FBR0		(0x020)	/* DMA Channel 0 Frame Branch Register */
+#define FBR1		(0x024)	/* DMA Channel 1 Frame Branch Register */
+#define FBR2		(0x028) /* DMA Channel 2 Frame Branch Register */
+#define FBR3		(0x02C) /* DMA Channel 2 Frame Branch Register */
+#define FBR4		(0x030) /* DMA Channel 2 Frame Branch Register */
+#define FBR5		(0x110) /* DMA Channel 2 Frame Branch Register */
+#define FBR6		(0x114) /* DMA Channel 2 Frame Branch Register */
+
 #define CMDCR		(0x100)	/* Command Control Register */
 #define PRSR		(0x104)	/* Panel Read Status Register */
 

drivers/video/pxafb.c

@@ -71,6 +71,7 @@
 static int pxafb_activate_var(struct fb_var_screeninfo *var,
 				struct pxafb_info *);
 static void set_ctrlr_state(struct pxafb_info *fbi, u_int state);
+static void setup_base_frame(struct pxafb_info *fbi, int branch);
 
 static unsigned long video_mem_size = 0;
 
@@ -467,6 +468,24 @@ static int pxafb_set_par(struct fb_info *info)
 	return 0;
 }
 
+static int pxafb_pan_display(struct fb_var_screeninfo *var,
+			     struct fb_info *info)
+{
+	struct pxafb_info *fbi = (struct pxafb_info *)info;
+	int dma = DMA_MAX + DMA_BASE;
+
+	if (fbi->state != C_ENABLE)
+		return 0;
+
+	setup_base_frame(fbi, 1);
+
+	if (fbi->lccr0 & LCCR0_SDS)
+		lcd_writel(fbi, FBR1, fbi->fdadr[dma + 1] | 0x1);
+
+	lcd_writel(fbi, FBR0, fbi->fdadr[dma] | 0x1);
+	return 0;
+}
+
 /*
  * pxafb_blank():
  *	Blank the display by setting all palette values to zero.  Note, the
@@ -506,6 +525,7 @@ static struct fb_ops pxafb_ops = {
 	.owner		= THIS_MODULE,
 	.fb_check_var	= pxafb_check_var,
 	.fb_set_par	= pxafb_set_par,
+	.fb_pan_display	= pxafb_pan_display,
 	.fb_setcolreg	= pxafb_setcolreg,
 	.fb_fillrect	= cfb_fillrect,
 	.fb_copyarea	= cfb_copyarea,
@@ -597,7 +617,7 @@ static int setup_frame_dma(struct pxafb_info *fbi, int dma, int pal,
 	struct pxafb_dma_descriptor *dma_desc, *pal_desc;
 	unsigned int dma_desc_off, pal_desc_off;
 
-	if (dma < 0 || dma >= DMA_MAX)
+	if (dma < 0 || dma >= DMA_MAX * 2)
 		return -EINVAL;
 
 	dma_desc = &fbi->dma_buff->dma_desc[dma];
@@ -607,7 +627,7 @@ static int setup_frame_dma(struct pxafb_info *fbi, int dma, int pal,
 	dma_desc->fidr  = 0;
 	dma_desc->ldcmd = size;
 
-	if (pal < 0 || pal >= PAL_MAX) {
+	if (pal < 0 || pal >= PAL_MAX * 2) {
 		dma_desc->fdadr = fbi->dma_buff_phys + dma_desc_off;
 		fbi->fdadr[dma] = fbi->dma_buff_phys + dma_desc_off;
 	} else {
@@ -633,6 +653,27 @@ static int setup_frame_dma(struct pxafb_info *fbi, int dma, int pal,
 	return 0;
 }
 
+static void setup_base_frame(struct pxafb_info *fbi, int branch)
+{
+	struct fb_var_screeninfo *var = &fbi->fb.var;
+	struct fb_fix_screeninfo *fix = &fbi->fb.fix;
+	unsigned int nbytes, offset;
+	int dma, pal, bpp = var->bits_per_pixel;
+
+	dma = DMA_BASE + (branch ? DMA_MAX : 0);
+	pal = (bpp >= 16) ? PAL_NONE : PAL_BASE + (branch ? PAL_MAX : 0);
+
+	nbytes = fix->line_length * var->yres;
+	offset = fix->line_length * var->yoffset;
+
+	if (fbi->lccr0 & LCCR0_SDS) {
+		nbytes = nbytes / 2;
+		setup_frame_dma(fbi, dma + 1, PAL_NONE, offset + nbytes, nbytes);
+	}
+
+	setup_frame_dma(fbi, dma, pal, offset, nbytes);
+}
+
 #ifdef CONFIG_FB_PXA_SMARTPANEL
 static int setup_smart_dma(struct pxafb_info *fbi)
 {
@@ -880,7 +921,6 @@ static int pxafb_activate_var(struct fb_var_screeninfo *var,
 			      struct pxafb_info *fbi)
 {
 	u_long flags;
-	size_t nbytes, offset;
 
 #if DEBUG_VAR
 	if (!(fbi->lccr0 & LCCR0_LCDT)) {
@@ -935,25 +975,14 @@ static int pxafb_activate_var(struct fb_var_screeninfo *var,
 #endif
 		setup_parallel_timing(fbi, var);
 
+	setup_base_frame(fbi, 0);
+
 	fbi->reg_lccr0 = fbi->lccr0 |
 		(LCCR0_LDM | LCCR0_SFM | LCCR0_IUM | LCCR0_EFM |
 		 LCCR0_QDM | LCCR0_BM  | LCCR0_OUM);
 
 	fbi->reg_lccr3 |= pxafb_bpp_to_lccr3(var);
 
-	nbytes = fbi->fb.fix.line_length * var->yres;
-	offset = fbi->fb.fix.line_length * var->yoffset;
-
-	if ((fbi->lccr0 & LCCR0_SDS) == LCCR0_Dual) {
-		nbytes = nbytes / 2;
-		setup_frame_dma(fbi, DMA_LOWER, PAL_NONE, offset + nbytes, nbytes);
-	}
-
-	if ((var->bits_per_pixel >= 16) || (fbi->lccr0 & LCCR0_LCDT))
-		setup_frame_dma(fbi, DMA_BASE, PAL_NONE, offset, nbytes);
-	else
-		setup_frame_dma(fbi, DMA_BASE, PAL_BASE, offset, nbytes);
-
 	fbi->reg_lccr4 = lcd_readl(fbi, LCCR4) & ~LCCR4_PAL_FOR_MASK;
 	fbi->reg_lccr4 |= (fbi->lccr4 & LCCR4_PAL_FOR_MASK);
 	local_irq_restore(flags);

drivers/video/pxafb.h

@@ -54,11 +54,14 @@ enum {
 #define PALETTE_SIZE	(256 * 4)
 #define CMD_BUFF_SIZE	(1024 * 50)
 
+/* NOTE: the palette and frame dma descriptors are doubled to allow
+ * the 2nd set for branch settings (FBRx)
+ */
 struct pxafb_dma_buff {
 	unsigned char palette[PAL_MAX * PALETTE_SIZE];
 	uint16_t cmd_buff[CMD_BUFF_SIZE];
-	struct pxafb_dma_descriptor pal_desc[PAL_MAX];
-	struct pxafb_dma_descriptor dma_desc[DMA_MAX];
+	struct pxafb_dma_descriptor pal_desc[PAL_MAX * 2];
+	struct pxafb_dma_descriptor dma_desc[DMA_MAX * 2];
 };
 
 struct pxafb_info {
@@ -71,7 +74,7 @@ struct pxafb_info {
 	struct pxafb_dma_buff	*dma_buff;
 	size_t			dma_buff_size;
 	dma_addr_t		dma_buff_phys;
-	dma_addr_t		fdadr[DMA_MAX];
+	dma_addr_t		fdadr[DMA_MAX * 2];
 
 	void __iomem		*video_mem;	/* virtual address of frame buffer */
 	unsigned long		video_mem_phys;	/* physical address of frame buffer */