Dne ponedeljek, 05. februar 2024 ob 18:50:27 CET je Frank Oltmanns napisal(a): > Hi Jernej, > > On 2024-02-05 at 18:45:27 +0100, Jernej Škrabec <jernej.skrabec@xxxxxxxxx> wrote: > > Dne ponedeljek, 05. februar 2024 ob 16:22:24 CET je Frank Oltmanns napisal(a): > >> The Allwinner A64 manual lists the following constraints for the > >> PLL-MIPI clock: > >> - M/N <= 3 > >> - (PLL_VIDEO0)/M >= 24MHz > >> > >> The PLL-MIPI clock is implemented as ccu_nkm. Therefore, add support for > >> these constraints. > >> > >> Signed-off-by: Frank Oltmanns <frank@xxxxxxxxxxxx> > > > > Haven't we discussed that this patch is unnecessary because same effect can > > be reached by limiting minimum frequency? > > The patch for ccu_nm was unnecessary: > https://lore.kernel.org/all/87jzoug2jz.fsf@xxxxxxxxxxxx/ > > Unfortunately, we still need this one. Ok, then: Reviewed-by: Jernej Skrabec <jernej.skrabec@xxxxxxxxx> Best regards, Jernej > > Best regards, > Frank > > > > > Best regards, > > Jernej > > > >> --- > >> drivers/clk/sunxi-ng/ccu_nkm.c | 21 +++++++++++++++++++++ > >> drivers/clk/sunxi-ng/ccu_nkm.h | 2 ++ > >> 2 files changed, 23 insertions(+) > >> > >> diff --git a/drivers/clk/sunxi-ng/ccu_nkm.c b/drivers/clk/sunxi-ng/ccu_nkm.c > >> index 853f84398e2b..1168d894d636 100644 > >> --- a/drivers/clk/sunxi-ng/ccu_nkm.c > >> +++ b/drivers/clk/sunxi-ng/ccu_nkm.c > >> @@ -16,6 +16,20 @@ struct _ccu_nkm { > >> unsigned long m, min_m, max_m; > >> }; > >> > >> +static bool ccu_nkm_is_valid_rate(struct ccu_common *common, unsigned long parent, > >> + unsigned long n, unsigned long m) > >> +{ > >> + struct ccu_nkm *nkm = container_of(common, struct ccu_nkm, common); > >> + > >> + if (nkm->max_m_n_ratio && (m > nkm->max_m_n_ratio * n)) > >> + return false; > >> + > >> + if (nkm->min_parent_m_ratio && (parent < nkm->min_parent_m_ratio * m)) > >> + return false; > >> + > >> + return true; > >> +} > >> + > >> static unsigned long ccu_nkm_find_best_with_parent_adj(struct ccu_common *common, > >> struct clk_hw *parent_hw, > >> unsigned long *parent, unsigned long rate, > >> @@ -31,6 +45,10 @@ static unsigned long ccu_nkm_find_best_with_parent_adj(struct ccu_common *common > >> unsigned long tmp_rate, tmp_parent; > >> > >> tmp_parent = clk_hw_round_rate(parent_hw, rate * _m / (_n * _k)); > >> + > >> + if (!ccu_nkm_is_valid_rate(common, tmp_parent, _n, _m)) > >> + continue; > >> + > >> tmp_rate = tmp_parent * _n * _k / _m; > >> > >> if (ccu_is_better_rate(common, rate, tmp_rate, best_rate) || > >> @@ -64,6 +82,9 @@ static unsigned long ccu_nkm_find_best(unsigned long parent, unsigned long rate, > >> for (_k = nkm->min_k; _k <= nkm->max_k; _k++) { > >> for (_n = nkm->min_n; _n <= nkm->max_n; _n++) { > >> for (_m = nkm->min_m; _m <= nkm->max_m; _m++) { > >> + if (!ccu_nkm_is_valid_rate(common, parent, _n, _m)) > >> + continue; > >> + > >> unsigned long tmp_rate; > >> > >> tmp_rate = parent * _n * _k / _m; > >> diff --git a/drivers/clk/sunxi-ng/ccu_nkm.h b/drivers/clk/sunxi-ng/ccu_nkm.h > >> index 6601defb3f38..c409212ee40e 100644 > >> --- a/drivers/clk/sunxi-ng/ccu_nkm.h > >> +++ b/drivers/clk/sunxi-ng/ccu_nkm.h > >> @@ -27,6 +27,8 @@ struct ccu_nkm { > >> struct ccu_mux_internal mux; > >> > >> unsigned int fixed_post_div; > >> + unsigned long max_m_n_ratio; > >> + unsigned long min_parent_m_ratio; > >> > >> struct ccu_common common; > >> }; > >> > >> >