Wolfgang Denk wd@denx.de writes:
Dear Matt,
I hope you are the right person to address this to - if not, please help to redirect to the current responsible developer.
Function pll_sigma_delta_val() in arch/arm/cpu/armv7/am33xx/clock_ti814x.c incorrectly uses "float" data, which results in FP operations which are not permitted in U-Boot.
The actual computation appears simple enough so a rewrite of the code without using any floating point operations should be fairly easy, but I don't understand the actual logic of this code, so I'd rather leave this to someone who does.
Could you please help and clean up these three lines of code?
Something like this should be equivalent. That said, it looks suspiciously like it's meant to simply do a division and round up. If that is the case, +225 should be +249. It probably makes no difference for the values actually encountered.
diff --git a/arch/arm/cpu/armv7/am33xx/clock_ti814x.c b/arch/arm/cpu/armv7/am33xx/clock_ti814x.c index ef14f47..9b5a47b 100644 --- a/arch/arm/cpu/armv7/am33xx/clock_ti814x.c +++ b/arch/arm/cpu/armv7/am33xx/clock_ti814x.c @@ -211,11 +211,8 @@ static u32 pll_dco_freq_sel(u32 clkout_dco) static u32 pll_sigma_delta_val(u32 clkout_dco) { u32 sig_val = 0; - float frac_div;
- frac_div = (float) clkout_dco / 250; - frac_div = frac_div + 0.90; - sig_val = (int)frac_div; + sig_val = (clkout_dco + 225) / 250; sig_val = sig_val << 24;
return sig_val;