clk: rockchip: fix frac settings of GPLL clock for rk3328
[ Upstream commit a0e447b0 ] 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>
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