Commit a0e447b0 by Katsuhiro Suzuki Committed by Heiko Stuebner

### clk: rockchip: fix frac settings of GPLL clock for rk3328

```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>```
parent bfeffd15
 ... ... @@ -78,17 +78,17 @@ static struct rockchip_pll_rate_table rk3328_pll_rates[] = { static struct rockchip_pll_rate_table rk3328_pll_frac_rates[] = { /* _mhz, _refdiv, _fbdiv, _postdiv1, _postdiv2, _dsmpd, _frac */ RK3036_PLL_RATE(1016064000, 3, 127, 1, 1, 0, 134217), RK3036_PLL_RATE(1016064000, 3, 127, 1, 1, 0, 134218), /* vco = 1016064000 */ RK3036_PLL_RATE(983040000, 24, 983, 1, 1, 0, 671088), RK3036_PLL_RATE(983040000, 24, 983, 1, 1, 0, 671089), /* vco = 983040000 */ RK3036_PLL_RATE(491520000, 24, 983, 2, 1, 0, 671088), RK3036_PLL_RATE(491520000, 24, 983, 2, 1, 0, 671089), /* vco = 983040000 */ RK3036_PLL_RATE(61440000, 6, 215, 7, 2, 0, 671088), RK3036_PLL_RATE(61440000, 6, 215, 7, 2, 0, 671089), /* vco = 860156000 */ RK3036_PLL_RATE(56448000, 12, 451, 4, 4, 0, 9797894), RK3036_PLL_RATE(56448000, 12, 451, 4, 4, 0, 9797895), /* vco = 903168000 */ RK3036_PLL_RATE(40960000, 12, 409, 4, 5, 0, 10066329), RK3036_PLL_RATE(40960000, 12, 409, 4, 5, 0, 10066330), /* vco = 819200000 */ { /* sentinel */ }, }; ... ...
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