The patch titled
neofb: simplify clock calculation
has been added to the -mm tree. Its filename is
neofb-simplify-clock-calculation.patch
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------------------------------------------------------
Subject: neofb: simplify clock calculation
From: Krzysztof Helt <krzysztof.h1@xxxxx>
There is nothing to gain by converting value in kHz to fixed point MHz.
Just calculate everything in kHz.
A reorder of the loop allows reducing number of iterations (check if
frequency is not too high already).
Signed-off-by: Krzysztof Helt <krzysztof.h1@xxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
drivers/video/neofb.c | 32 ++++++++++++++------------------
1 file changed, 14 insertions(+), 18 deletions(-)
diff -puN drivers/video/neofb.c~neofb-simplify-clock-calculation drivers/video/neofb.c
--- a/drivers/video/neofb.c~neofb-simplify-clock-calculation
+++ a/drivers/video/neofb.c
@@ -201,7 +201,6 @@ static int neoFindMode(int xres, int yre
*
* Determine the closest clock frequency to the one requested.
*/
-#define REF_FREQ 0xe517 /* 14.31818 in 20.12 fixed point */
#define MAX_N 127
#define MAX_D 31
#define MAX_F 1
@@ -211,27 +210,24 @@ static void neoCalcVCLK(const struct fb_
{
int n, d, f;
int n_best = 0, d_best = 0, f_best = 0;
- long f_best_diff = (0x7ffff << 12); /* 20.12 */
- long f_target = (freq << 12) / 1000; /* 20.12 */
+ long f_best_diff = 0x7ffff;
for (f = 0; f <= MAX_F; f++)
- for (n = 0; n <= MAX_N; n++)
- for (d = 0; d <= MAX_D; d++) {
- long f_out; /* 20.12 */
- long f_diff; /* 20.12 */
-
- f_out =
- ((((n + 1) << 12) / ((d +
- 1) *
- (1 << f))) >> 12)
- * REF_FREQ;
- f_diff = abs(f_out - f_target);
- if (f_diff < f_best_diff) {
+ for (d = 0; d <= MAX_D; d++)
+ for (n = 0; n <= MAX_N; n++) {
+ long f_out;
+ long f_diff;
+
+ f_out = ((14318 * (n + 1)) / (d + 1)) >> f;
+ f_diff = abs(f_out - freq);
+ if (f_diff <= f_best_diff) {
f_best_diff = f_diff;
n_best = n;
d_best = d;
f_best = f;
}
+ if (f_out > freq)
+ break;
}
if (info->fix.accel == FB_ACCEL_NEOMAGIC_NM2200 ||
@@ -248,11 +244,11 @@ static void neoCalcVCLK(const struct fb_
par->VCLK3Denominator = d_best;
#ifdef NEOFB_DEBUG
- printk("neoVCLK: f:%d NumLow=%d NumHi=%d Den=%d Df=%d\n",
- f_target >> 12,
+ printk(KERN_DEBUG "neoVCLK: f:%ld NumLow=%d NumHi=%d Den=%d Df=%ld\n",
+ freq,
par->VCLK3NumeratorLow,
par->VCLK3NumeratorHigh,
- par->VCLK3Denominator, f_best_diff >> 12);
+ par->VCLK3Denominator, f_best_diff);
#endif
}
_
Patches currently in -mm which might be from krzysztof.h1@xxxxx are
tridentfb-replace-macros-with-functions.patch
tridentfb-convert-fb_info-into-allocated-one.patch
tridentfb-move-global-pseudo-palette-into-structure.patch
tridentfb-move-global-chip_id-into-structure.patch
tridentfb-move-global-flat-panel-variable-into-structure.patch
tridentfb-convert-is_blade-and-is_xp-macros-into-functions.patch
tridentfb-move-global-acceleration-hooks-into-structure.patch
tridentfb-make-use-of-functions-and-constants-from-the-vgah.patch
tridentfb-fix-timing-calculations.patch
tridentfb-use-mmio-access-for-clock-setting.patch
tridentfb-fix-clock-settings-for-older-trident-96xx-chips.patch
tridentfb-improve-probe-function.patch
tridentfb-improved-register-values-on-tgui-9680.patch
tridentfb-add-tgui-9440-support.patch
tridentfb-fix-unitialized-pseudo_palette.patch
tridentfb-improve-check_var-function.patch
tridentfb-preserve-memory-type-settings.patch
tridentfb-fix-hi-color-modes-for-tgui-9440.patch
tridentfb-add-acceleration-for-tgui-families.patch
tridentfb-acceleration-code-improvements.patch
tridentfb-acceleration-bug-fixes.patch
tridentfb-various-pixclock-and-timing-improvements.patch
tridentfb-acceleration-constants-change.patch
tridentfb-source-code-improvements.patch
tridentfb-fix-console-freeze-when-switching-from-x11.patch
tridentfb-fix-224-color-logo-at-8-bpp.patch
tridentfb-y-panning-fixes.patch
tridentfb-blade3d-clock-fixes.patch
amifb-test-virtual-screen-range-before-subtraction-on-unsigned.patch
atafb-test-virtual-screen-range-before-subtraction-on-unsigned.patch
fbcon-make-logo_height-a-local-variable.patch
uvesafb-change-mode-parameter-to-mode_option.patch
tridentfb-documentation-update.patch
tdfxfb-add-mode_option-module-parameter.patch
vga16fb-source-code-improvement.patch
tdfxfb-remove-ypan-checks-done-by-a-higher-layer.patch
vfb-only-enable-if-explicitly-requested-when-compiled-in.patch
hgafb-convert-to-new-platform-driver-api-bugzilla-9689.patch
skeletonfb-update-to-correct-platform-driver-usage.patch
neofb-simplify-clock-calculation.patch
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