mirrors/u-boot
1
0
Fork 0
mirror of https://source.denx.de/u-boot/u-boot.git synced 2025-10-17 10:31:38 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity

sunxi: Fix pll1 clock calculation

Browse Source 
clock_sun6i.c is used for sun6i, sun8i and sun50i SoC families.
PLL1 clock sets the default system clock, defined as:
  sun6i: 1008000000
  sun8i: 1008000000
  sun50i: 816000000

With the current calculation, m = 2 and k = 3. Solving for n,
this results 28. Solving back:
  (24MHz * 28 * 3) / 2 = 1008MHz

However if the requested clock is 816, n is 22.66 rounded
to 22, which results:
  (24MHz * 28 * 3) / 2 = 792MHz

Changing k to 4 satisfies both system clocks:
  (24E6 * 21 * 4) / 2 = 1008MHz
  (24E6 * 17 * 4) / 2 = 816MHz

Signed-off-by: Stefan Mavrodiev <stefan@olimex.com>
Acked-by: Jagan Teki <jagan@amarulasolutions.com>
This commit is contained in:
Stefan Mavrodiev 2019-07-31 16:15:52 +03:00 committed by Jagan Teki
parent 4ed293ae79
commit e6467df1eb
1 changed files with 1 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
arch/arm/mach-sunxi/clock_sun6i.c
View File

@ -118,7 +118,7 @@ void clock_set_pll1(unsigned int clk)
if (clk > 1152000000) { if (clk > 1152000000) {
k = 2; k = 2;
} else if (clk > 768000000) { } else if (clk > 768000000) {
k = 3; k = 4;
m = 2; m = 2;
} }