gk20a_clk_ctor
ret = gk20a_clk_ctor(device, type, inst, &gk20a_clk, &gk20a_pllg_params, clk);
int gk20a_clk_ctor(struct nvkm_device *, enum nvkm_subdev_type, int, const struct nvkm_clk_func *,
ret = gk20a_clk_ctor(device, type, inst, &gm20b_clk, clk_params, &clk->base);
ret = gk20a_clk_ctor(device, type, inst, &gm20b_clk_speedo0, &gm20b_pllg_params, clk);