[media] vivid: move PRINTSTR to separate functions

Commit 84cb7be43cec12868e94163c99fdc34c0297c3b8 broke vivid-tpg
(uninitialized variable p).

This patch takes a different approach: four different functions are
created, one for each PRINTSTR version.

In order to avoid the 'the frame size of 1308 bytes is larger than 1024
bytes' warning I had to mark those functions with 'noinline'. For
whatever reason gcc seems to inline this aggressively and it is doing
weird things with the stack.

I tried to read the assembly code, but I couldn't see what exactly it
was doing on the stack.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

diff --git a/drivers/media/platform/vivid/vivid-tpg.c b/drivers/media/platform/vivid/vivid-tpg.c
index c86c8ffcf9c7083c707383051b6b7107f18c422e..32ebf0d90d10e60e7ac61e3fb3e85f0832734606 100644 (file)
--- a/drivers/media/platform/vivid/vivid-tpg.c
+++ b/drivers/media/platform/vivid/vivid-tpg.c
@@ -1462,40 +1462,10 @@ static void tpg_precalculate_line(struct tpg_data *tpg)
 /* need this to do rgb24 rendering */
 typedef struct { u16 __; u8 _; } __packed x24;
 
-void tpg_gen_text(const struct tpg_data *tpg, u8 *basep[TPG_MAX_PLANES][2],
-                 int y, int x, char *text)
-{
-       int line;
-       unsigned step = V4L2_FIELD_HAS_T_OR_B(tpg->field) ? 2 : 1;
-       unsigned div = step;
-       unsigned first = 0;
-       unsigned len = strlen(text);
-       unsigned p;
-
-       if (font8x16 == NULL || basep == NULL)
-               return;
-
-       /* Checks if it is possible to show string */
-       if (y + 16 >= tpg->compose.height || x + 8 >= tpg->compose.width)
-               return;
-
-       if (len > (tpg->compose.width - x) / 8)
-               len = (tpg->compose.width - x) / 8;
-       if (tpg->vflip)
-               y = tpg->compose.height - y - 16;
-       if (tpg->hflip)
-               x = tpg->compose.width - x - 8;
-       y += tpg->compose.top;
-       x += tpg->compose.left;
-       if (tpg->field == V4L2_FIELD_BOTTOM)
-               first = 1;
-       else if (tpg->field == V4L2_FIELD_SEQ_TB || tpg->field == V4L2_FIELD_SEQ_BT)
-               div = 2;
-
-       /* Print text */
-#define PRINTSTR(PIXTYPE) for (p = 0; p < tpg->planes; p++) {  \
-       unsigned vdiv = tpg->vdownsampling[p];  \
-       unsigned hdiv = tpg->hdownsampling[p];  \
+#define PRINTSTR(PIXTYPE) do { \
+       unsigned vdiv = tpg->vdownsampling[p]; \
+       unsigned hdiv = tpg->hdownsampling[p]; \
+       int line;       \
        PIXTYPE fg;     \
        PIXTYPE bg;     \
        memcpy(&fg, tpg->textfg[p], sizeof(PIXTYPE));   \
@@ -1546,19 +1516,83 @@ void tpg_gen_text(const struct tpg_data *tpg, u8 *basep[TPG_MAX_PLANES][2],
        }       \
 } while (0)
 
-       switch (tpg->twopixelsize[p]) {
-       case 2:
-               PRINTSTR(u8);
-               break;
-       case 4:
-               PRINTSTR(u16);
-               break;
-       case 6:
-               PRINTSTR(x24);
-               break;
-       case 8:
-               PRINTSTR(u32);
-               break;
+static noinline void tpg_print_str_2(const struct tpg_data *tpg, u8 *basep[TPG_MAX_PLANES][2],
+                       unsigned p, unsigned first, unsigned div, unsigned step,
+                       int y, int x, char *text, unsigned len)
+{
+       PRINTSTR(u8);
+}
+
+static noinline void tpg_print_str_4(const struct tpg_data *tpg, u8 *basep[TPG_MAX_PLANES][2],
+                       unsigned p, unsigned first, unsigned div, unsigned step,
+                       int y, int x, char *text, unsigned len)
+{
+       PRINTSTR(u16);
+}
+
+static noinline void tpg_print_str_6(const struct tpg_data *tpg, u8 *basep[TPG_MAX_PLANES][2],
+                       unsigned p, unsigned first, unsigned div, unsigned step,
+                       int y, int x, char *text, unsigned len)
+{
+       PRINTSTR(x24);
+}
+
+static noinline void tpg_print_str_8(const struct tpg_data *tpg, u8 *basep[TPG_MAX_PLANES][2],
+                       unsigned p, unsigned first, unsigned div, unsigned step,
+                       int y, int x, char *text, unsigned len)
+{
+       PRINTSTR(u32);
+}
+
+void tpg_gen_text(const struct tpg_data *tpg, u8 *basep[TPG_MAX_PLANES][2],
+                 int y, int x, char *text)
+{
+       unsigned step = V4L2_FIELD_HAS_T_OR_B(tpg->field) ? 2 : 1;
+       unsigned div = step;
+       unsigned first = 0;
+       unsigned len = strlen(text);
+       unsigned p;
+
+       if (font8x16 == NULL || basep == NULL)
+               return;
+
+       /* Checks if it is possible to show string */
+       if (y + 16 >= tpg->compose.height || x + 8 >= tpg->compose.width)
+               return;
+
+       if (len > (tpg->compose.width - x) / 8)
+               len = (tpg->compose.width - x) / 8;
+       if (tpg->vflip)
+               y = tpg->compose.height - y - 16;
+       if (tpg->hflip)
+               x = tpg->compose.width - x - 8;
+       y += tpg->compose.top;
+       x += tpg->compose.left;
+       if (tpg->field == V4L2_FIELD_BOTTOM)
+               first = 1;
+       else if (tpg->field == V4L2_FIELD_SEQ_TB || tpg->field == V4L2_FIELD_SEQ_BT)
+               div = 2;
+
+       for (p = 0; p < tpg->planes; p++) {
+               /* Print text */
+               switch (tpg->twopixelsize[p]) {
+               case 2:
+                       tpg_print_str_2(tpg, basep, p, first, div, step, y, x,
+                                       text, len);
+                       break;
+               case 4:
+                       tpg_print_str_4(tpg, basep, p, first, div, step, y, x,
+                                       text, len);
+                       break;
+               case 6:
+                       tpg_print_str_6(tpg, basep, p, first, div, step, y, x,
+                                       text, len);
+                       break;
+               case 8:
+                       tpg_print_str_8(tpg, basep, p, first, div, step, y, x,
+                                       text, len);
+                       break;
+               }
        }
 }