Re: Console rotation problems
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: 2005-11-24 03:09:43
Also in:
lkml
Remove bogus usage of test/set_bit() from fbcon rotation code and just manipulate the bits directly. This fixes an oops on powerpc among others and should be faster. Seems to work fine on the G5 here. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> --- And here is the fix. Tony, did I miss something ? Index: linux-serialfix/drivers/video/console/fbcon_rotate.h ===================================================================
--- linux-serialfix.orig/drivers/video/console/fbcon_rotate.h 2005-11-23 11:07:23.000000000 +1100
+++ linux-serialfix/drivers/video/console/fbcon_rotate.h 2005-11-24 14:02:22.000000000 +1100@@ -21,21 +21,13 @@ (s == SCROLL_REDRAW || s == SCROLL_MOVE || !(i)->fix.xpanstep) ? \ (i)->var.xres : (i)->var.xres_virtual; }) -/* - * The bitmap is always big endian - */ -#if defined(__LITTLE_ENDIAN) -#define FBCON_BIT(b) (7 - (b)) -#else -#define FBCON_BIT(b) (b) -#endif static inline int pattern_test_bit(u32 x, u32 y, u32 pitch, const char *pat) { u32 tmp = (y * pitch) + x, index = tmp / 8, bit = tmp % 8; pat +=index; - return (test_bit(FBCON_BIT(bit), (void *)pat)); + return (*pat) & (0x80 >> bit); } static inline void pattern_set_bit(u32 x, u32 y, u32 pitch, char *pat)
@@ -43,7 +35,8 @@ static inline void pattern_set_bit(u32 x u32 tmp = (y * pitch) + x, index = tmp / 8, bit = tmp % 8; pat += index; - set_bit(FBCON_BIT(bit), (void *)pat); + + (*pat) |= 0x80 >> bit; } static inline void rotate_ud(const char *in, char *out, u32 width, u32 height)
Index: linux-serialfix/drivers/video/console/fbcon_ccw.c ===================================================================
--- linux-serialfix.orig/drivers/video/console/fbcon_ccw.c 2005-11-15 11:54:14.000000000 +1100
+++ linux-serialfix/drivers/video/console/fbcon_ccw.c 2005-11-24 14:03:48.000000000 +1100@@ -34,7 +34,7 @@ static inline void ccw_update_attr(u8 *d msk <<= (8 - mod); if (offset > mod) - set_bit(FBCON_BIT(7), (void *)&msk1); + msk1 |= 0x01; for (i = 0; i < vc->vc_font.width; i++) { for (j = 0; j < width; j++) {