diff options
| author | Katsuhiro Suzuki <katsuhiro@katsuster.net> | 2018-12-23 01:42:49 +0900 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-04-05 22:33:16 +0200 |
| commit | 7386f095b7097f669dda3c4efd6ec47d7468ef83 (patch) | |
| tree | 7c6efbe3764658fa95c8f59a5e94655dde7ea00e /certs | |
| parent | c8e4f8406842332fb55cd792016e5dac266f6354 (diff) | |
clk: rockchip: fix frac settings of GPLL clock for rk3328
[ Upstream commit a0e447b0c50240a90ab84b7126b3c06b0bab4adc ]
This patch fixes settings of GPLL frequency in fractional mode for
rk3328. In this mode, FOUTVCO is calcurated by following formula:
FOUTVCO = FREF * FBDIV / REFDIV + ((FREF * FRAC / REFDIV) >> 24)
The problem is in FREF * FRAC >> 24 term. This result always lacks
one from target value is specified by rate member. For example first
itme of rk3328_pll_frac_rate originally has
- rate : 1016064000
- refdiv: 3
- fbdiv : 127
- frac : 134217
- FREF * FBDIV / REFDIV = 1016000000
- (FREF * FRAC / REFDIV) >> 24 = 63999
Thus calculated rate is 1016063999. It seems wrong.
If frac has 134218 (it is increased 1 from original value), second
term is 64000. All other items have same situation. So this patch
adds 1 to frac member in all items of rk3328_pll_frac_rate.
Signed-off-by: Katsuhiro Suzuki <katsuhiro@katsuster.net>
Acked-by: Elaine Zhang <zhangqing@rock-chips.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'certs')
0 files changed, 0 insertions, 0 deletions