s3c-fb: add SHADOWCON shadow register locking support for S5PV210

S5PV210 allows per-window locking of register value updates from shadow
registers.

Signed-off-by: Pawel Osciak <p.osciak@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: InKi Dae <inki.dae@samsung.com>
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 36 insertions, 4 deletions

diff --git a/drivers/video/s3c-fb.c b/drivers/video/s3c-fb.c
index 6cbddc445f03..f76791180dbe 100644
--- a/drivers/video/s3c-fb.c
+++ b/drivers/video/s3c-fb.c
@@ -79,6 +79,7 @@ struct s3c_fb;
  * @osd: The base for the OSD registers.
  * @palette: Address of palette memory, or 0 if none.
  * @has_prtcon: Set if has PRTCON register.
+ * @has_shadowcon: Set if has SHADOWCON register.
  */
 struct s3c_fb_variant {
         unsigned int    is_2443:1;
@@ -95,6 +96,7 @@ struct s3c_fb_variant {
         unsigned short  palette[S3C_FB_MAX_WIN];
 
         unsigned int    has_prtcon:1;
+        unsigned int    has_shadowcon:1;
 };
 
 /**
@@ -363,6 +365,36 @@ static int s3c_fb_align_word(unsigned int bpp, unsigned int pix)
 }
 
 /**
+ * shadow_protect_win() - disable updating values from shadow registers at vsync
+ *
+ * @win: window to protect registers for
+ * @protect: 1 to protect (disable updates)
+ */
+static void shadow_protect_win(struct s3c_fb_win *win, bool protect)
+{
+        struct s3c_fb *sfb = win->parent;
+        u32 reg;
+
+        if (protect) {
+                if (sfb->variant.has_prtcon) {
+                        writel(PRTCON_PROTECT, sfb->regs + PRTCON);
+                } else if (sfb->variant.has_shadowcon) {
+                        reg = readl(sfb->regs + SHADOWCON);
+                        writel(reg | SHADOWCON_WINx_PROTECT(win->index),
+                                sfb->regs + SHADOWCON);
+                }
+        } else {
+                if (sfb->variant.has_prtcon) {
+                        writel(0, sfb->regs + PRTCON);
+                } else if (sfb->variant.has_shadowcon) {
+                        reg = readl(sfb->regs + SHADOWCON);
+                        writel(reg & ~SHADOWCON_WINx_PROTECT(win->index),
+                                sfb->regs + SHADOWCON);
+                }
+        }
+}
+
+/**
  * s3c_fb_set_par() - framebuffer request to set new framebuffer state.
  * @info: The framebuffer to change.
  *
@@ -810,14 +842,12 @@ static int s3c_fb_pan_display(struct fb_var_screeninfo *var,
 
         /* Temporarily turn off per-vsync update from shadow registers until
          * both start and end addresses are updated to prevent corruption */
-        if (sfb->variant.has_prtcon)
-                writel(PRTCON_PROTECT, sfb->regs + PRTCON);
+        shadow_protect_win(win, 1);
 
         writel(info->fix.smem_start + start_boff, buf + sfb->variant.buf_start);
         writel(info->fix.smem_start + end_boff, buf + sfb->variant.buf_end);
 
-        if (sfb->variant.has_prtcon)
-                writel(0, sfb->regs + PRTCON);
+        shadow_protect_win(win, 0);
 
         return 0;
 }
@@ -1530,6 +1560,8 @@ static struct s3c_fb_driverdata s3c_fb_data_s5pv210 __devinitdata = {
                         [3] = 0x3000,
                         [4] = 0x3400,
                 },
+
+                .has_shadowcon  = 1,
         },
         .win[0] = &s3c_fb_data_64xx_wins[0],
         .win[1] = &s3c_fb_data_64xx_wins[1],