UbiquitousOS
/
OpenCloudOS-Kernel
mirror of https://gitee.com/OpenCloudOS/OpenCloudOS-Kernel.git
11
0
Fork 0
Code Issues Projects Releases Wiki Activity

gpu: ipu-v3: Fix dev_dbg frequency output 

This commit corrects the printing of the IPU clock error percentage if
it is between -0.1% to -0.9%. For example, if the pixel clock requested
is 27.2 MHz but only 27.0 MHz can be achieved the deviation is -0.8%.
But the fixed point math had a flaw and calculated error of 0.2%.

Before:
  Clocks: IPU 270000000Hz DI 24716667Hz Needed 27200000Hz
  IPU clock can give 27000000 with divider 10, error 0.2%
  Want 27200000Hz IPU 270000000Hz DI 24716667Hz using IPU, 27000000Hz

After:
  Clocks: IPU 270000000Hz DI 24716667Hz Needed 27200000Hz
  IPU clock can give 27000000 with divider 10, error -0.8%
  Want 27200000Hz IPU 270000000Hz DI 24716667Hz using IPU, 27000000Hz

Signed-off-by: Leo Ruan <tingquan.ruan@cn.bosch.com>
Signed-off-by: Mark Jonas <mark.jonas@de.bosch.com>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Link: https://lore.kernel.org/r/20220207151411.5009-1-mark.jonas@de.bosch.com
This commit is contained in:
Leo Ruan 2022-02-07 16:14:11 +01:00 committed by Philipp Zabel
parent e8083acc3f
commit 070a88fd4a
1 changed files with 3 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
drivers/gpu/ipu-v3/ipu-di.c
View File

@ -447,8 +447,9 @@ static void ipu_di_config_clock(struct ipu_di *di,
error = rate / (sig->mode.pixelclock / 1000);
dev_dbg(di->ipu->dev, " IPU clock can give %lu with divider %u, error %d.%u%%\n",
rate, div, (signed)(error - 1000) / 10, error % 10);
dev_dbg(di->ipu->dev, " IPU clock can give %lu with divider %u, error %c%d.%d%%\n",
rate, div, error < 1000 ? '-' : '+',
abs(error - 1000) / 10, abs(error - 1000) % 10);
/* Allow a 1% error */
if (error < 1010 && error >= 990) {