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25 #include <subdev/clock.h>
26 #include <subdev/bios.h>
27 #include <subdev/bios/pll.h>
32 nva3_pll_calc(struct nouveau_subdev *subdev, struct nvbios_pll *info,
33 u32 freq, int *pN, int *pfN, int *pM, int *P)
35 u32 best_err = ~0, err;
38 *P = info->vco1.max_freq / freq;
44 lM = (info->refclk + info->vco1.max_inputfreq) / info->vco1.max_inputfreq;
45 lM = max(lM, (int)info->vco1.min_m);
46 hM = (info->refclk + info->vco1.min_inputfreq) / info->vco1.min_inputfreq;
47 hM = min(hM, (int)info->vco1.max_m);
50 for (M = lM; M <= hM; M++) {
51 u32 tmp = freq * *P * M;
52 N = tmp / info->refclk;
53 fN = tmp % info->refclk;
56 if (fN >= info->refclk / 2)
59 if (fN < info->refclk / 2)
61 fN = tmp - (N * info->refclk);
64 if (N < info->vco1.min_n)
66 if (N > info->vco1.max_n)
69 err = abs(freq - (info->refclk * N / M / *P));
77 *pfN = ((fN << 13) + info->refclk / 2) / info->refclk;
78 *pfN = (*pfN - 4096) & 0xffff;
83 if (unlikely(best_err == ~0)) {
84 nv_error(subdev, "unable to find matching pll values\n");
88 return info->refclk * *pN / *pM / *P;