| Message ID | 20230807-pll-mipi_set_rate_parent-v6-0-f173239a4b59@oltmanns.dev (mailing list archive) |
|---|---|
| Headers | show |
| Series | clk: sunxi-ng: Consider alternative parent rates when determining NKM clock rate | expand |
On Mon, Aug 7, 2023 at 8:44 PM Frank Oltmanns <frank@oltmanns.dev> wrote: > > This patchset enables NKM clocks to consider alternative parent rates > and utilize this new feature to adjust the pll-video0 clock on Allwinner > A64. > > Furthermore, with this patchset pll-video0 considers rates that are > higher than the requested rate when finding the closest rate. In > consequence, higher rates are also considered by pll-video0's > descandents. In total, after applying this patchset, finding the closest > rate is supported by: > - ccu_nm > - ccu_nkm > - ccu_mux > - ccu_div > > This allows us to achieve an optimal rate for driving the board's panel. > > To provide some context, the clock structure involved in this process is > as follows: > clock clock type > -------------------------------------- > pll-video0 ccu_nm > pll-mipi ccu_nkm > tcon0 ccu_mux > tcon-data-clock sun4i_dclk > > The divider between tcon0 and tcon-data-clock is fixed at 4. Therefore, > in order to achieve a rate that closely matches the desired rate of the > panel, pll-mipi needs to operate at a specific rate. > > Tests > ===== > So far, this has been successfully tested on the A64-based Pinephone > using three different panel rates: > > 1. A panel rate that can be matched exactly by pll-video0. > 2. A panel rate that requires pll-video0 to undershoot to get the > closest rate. > 3. A panel rate that requires pll-video0 to overshoot to get the > closest rate. > > Test records: > > Re 1: > ----- > Panel requests tcon-data-clock of 103500000 Hz, i.e., pll-mipi needs to > run at 414000000 Hz. This results in the following clock rates: > clock rate > ------------------------------------- > pll-video0 207000000 > hdmi-phy-clk 51750000 > hdmi 207000000 > tcon1 207000000 > pll-mipi 414000000 > tcon0 414000000 > tcon-data-clock 103500000 > > The results of the find_best calls: > ccu_nkm_find_best_with_parent_adj: rate=414000000, best_rate=414000000, best_parent_rate=207000000, n=1, k=2, m=1 > ccu_nkm_find_best_with_parent_adj: rate=414000000, best_rate=414000000, best_parent_rate=207000000, n=1, k=2, m=1 > ccu_nkm_find_best_with_parent_adj: rate=414000000, best_rate=414000000, best_parent_rate=207000000, n=1, k=2, m=1 > ccu_nkm_find_best_with_parent_adj: rate=414000000, best_rate=414000000, best_parent_rate=207000000, n=1, k=2, m=1 > ccu_nkm_find_best: rate=414000000, best_rate=414000000, parent_rate=207000000, n=1, k=2, m=1 > > Re 2: > ----- > Panel requests tcon-data-clock of 103650000 Hz, i.e., pll-mipi needs to > run at 414600000 Hz. This results in the following clock rates: > clock rate > ------------------------------------- > pll-video0 282666666 > hdmi-phy-clk 70666666 > hdmi 282666666 > tcon1 282666666 > pll-mipi 414577776 > tcon0 414577776 > tcon-data-clock 103644444 > > The results of the find_best calls: > ccu_nkm_find_best_with_parent_adj: rate=414600000, best_rate=414577776, best_parent_rate=282666666, n=11, k=2, m=15 > ccu_nkm_find_best_with_parent_adj: rate=414600000, best_rate=414577776, best_parent_rate=282666666, n=11, k=2, m=15 > ccu_nkm_find_best_with_parent_adj: rate=414577776, best_rate=414577776, best_parent_rate=282666666, n=11, k=2, m=15 > ccu_nkm_find_best_with_parent_adj: rate=414577776, best_rate=414577776, best_parent_rate=282666666, n=11, k=2, m=15 > ccu_nkm_find_best: rate=414577776, best_rate=414577776, parent_rate=282666666, n=11, k=2, m=15 > > Re 3: > ----- > Panel requests tcon-data-clock of 112266000 Hz, i.e., pll-mipi needs to > run at 449064000 Hz. This results in the following clock rates: > clock rate > ------------------------------------- > pll-video0 207272727 > hdmi-phy-clk 51818181 > hdmi 207272727 > tcon1 207272727 > pll-mipi 449090908 > tcon0 449090908 > tcon-data-clock 112272727 > > The results of the find_best calls: > ccu_nkm_find_best_with_parent_adj: rate=449064000, best_rate=449090908, best_parent_rate=207272727, n=13, k=2, m=12 > ccu_nkm_find_best_with_parent_adj: rate=449064000, best_rate=449090908, best_parent_rate=207272727, n=13, k=2, m=12 > ccu_nkm_find_best_with_parent_adj: rate=449090908, best_rate=449090908, best_parent_rate=207272727, n=13, k=2, m=12 > ccu_nkm_find_best_with_parent_adj: rate=449090908, best_rate=449090908, best_parent_rate=207272727, n=13, k=2, m=12 > ccu_nkm_find_best: rate=449090908, best_rate=449090908, parent_rate=207272727, n=13, k=2, m=12 > > Changelog: > ---------- > Changes in v6: > - Removed unnecessary #include from ccu_nkm.c > - Link to v5: https://lore.kernel.org/r/20230806-pll-mipi_set_rate_parent-v5-0-db4f5ca33fc3@oltmanns.dev > > Changes in v5: > - Remove the dedicated function for calculating the optimal parent rate > for nkm clocks that was introduced in v2 and again in v4. Instead use > a simple calculation and require the parent clock to select the > closest rate to achieve optimal results. > - Change the order of parameters of nkm_best_rate and > nkm_best_rate_with_parent_adj as requested my Maxime Ripard. > - Prefer to not reset the rate of the nkm clock's parent if the ideal > rate can be reached using the parent's current rate, copying the > behavior of ccu_mp. > - Link to v4: https://lore.kernel.org/r/20230717-pll-mipi_set_rate_parent-v4-0-04acf1d39765@oltmanns.dev > > Changes in v4: > - Re-introduce a dedicated function for calculating the optimal parent > rate for nkm clocks that was introduced in v2 and removed in v3. It > turned out that not having this functionality introduces a bug when > the parent does not support finding the closest rate: > https://lore.kernel.org/all/87pm4xg2ub.fsf@oltmanns.dev/ > - Incorporate review remarks: > - Correcting the parameter name for ccu_nkm_round_rate()'s parent HW > is now in a separate patch. > - Use correct parameter order in ccu_nkm_find_best_with_parent_adj. > - Add ccu_is_better_rate() and use it for determining the best rate > for nm and nkm, as well as ccu_mux_helper_determine_rate. > - Consistently introduce new macros for clock variants that support > finding the closest rate instead of updating existing macros. > - Use wrapper function for determining a ccu_mux's rate in order to > support finding the closest rate. > - Link to v3: https://lore.kernel.org/r/20230702-pll-mipi_set_rate_parent-v3-0-46dcb8aa9cbc@oltmanns.dev > > Changes in v3: > - Use dedicated function for finding the best rate in cases where an > nkm clock supports setting its parent's rate, streamlining it with > the structure that is used in other sunxi-ng ccus such as ccu_mp > (PATCH 1). > - Therefore, remove the now obsolete comments that were introduced in > v2 (PATCH 1). > - Remove the dedicated function for calculating the optimal parent rate > for nkm clocks that was introduced in v2. Instead use a simple > calculation and require the parent clock to select the closest rate to > achieve optimal results (PATCH 1). > - Therefore, add support to set the closest rate for nm clocks (because > pll-mipi's parent pll-video0 is an nm clock) and all clock types that > are descendants of a64's pll-video0, i.e., nkm, mux, and div (PATCH 3 > et. seq.). > - Link to v2: https://lore.kernel.org/all/20230611090143.132257-1-frank@oltmanns.dev/ > > Changes in V2: > - Move optimal parent rate calculation to dedicated function > - Choose a parent rate that does not to overshoot requested rate > - Add comments to ccu_nkm_find_best > - Make sure that best_parent_rate stays at original parent rate in the unlikely > case that all combinations overshoot. > > Link to V1: > https://lore.kernel.org/lkml/20230605190745.366882-1-frank@oltmanns.dev/ > > --- > Frank Oltmanns (11): > clk: sunxi-ng: nkm: Use correct parameter name for parent HW > clk: sunxi-ng: nkm: consider alternative parent rates when determining rate > clk: sunxi-ng: a64: allow pll-mipi to set parent's rate > clk: sunxi-ng: Add feature to find closest rate > clk: sunxi-ng: Add helper function to find closest rate > clk: sunxi-ng: nm: Support finding closest rate > clk: sunxi-ng: nkm: Support finding closest rate > clk: sunxi-ng: mux: Support finding closest rate > clk: sunxi-ng: div: Support finding closest rate > clk: sunxi-ng: a64: select closest rate for pll-video0 > clk: sunxi-ng: nkm: Prefer current parent rate Whole series applied. There were some conflicts on patch 10 I had to fix up. I also took the liberty of realigning some of the lines. Please check if things are correct: https://git.kernel.org/pub/scm/linux/kernel/git/sunxi/linux.git/commit/?h=sunxi/clk-for-6.6&id=bf8eb12f52c49e10ca1d86564bfa096e09c51c38 ChenYu > drivers/clk/sunxi-ng/ccu-sun50i-a64.c | 36 ++++++++++------------- > drivers/clk/sunxi-ng/ccu_common.c | 12 ++++++++ > drivers/clk/sunxi-ng/ccu_common.h | 6 ++++ > drivers/clk/sunxi-ng/ccu_div.h | 30 +++++++++++++++++++ > drivers/clk/sunxi-ng/ccu_mux.c | 15 ++++++++-- > drivers/clk/sunxi-ng/ccu_mux.h | 38 +++++++++++++++++------- > drivers/clk/sunxi-ng/ccu_nkm.c | 55 ++++++++++++++++++++++++++++++----- > drivers/clk/sunxi-ng/ccu_nm.c | 13 ++++----- > drivers/clk/sunxi-ng/ccu_nm.h | 48 ++++++++++++++++++++++++++++-- > 9 files changed, 202 insertions(+), 51 deletions(-) > --- > base-commit: 6995e2de6891c724bfeb2db33d7b87775f913ad1 > change-id: 20230626-pll-mipi_set_rate_parent-3363fc0d6e6f > > Best regards, > -- > Frank Oltmanns <frank@oltmanns.dev> >
On 2023-08-10 at 00:44:53 +0800, Chen-Yu Tsai <wens@csie.org> wrote: > On Mon, Aug 7, 2023 at 8:44 PM Frank Oltmanns <frank@oltmanns.dev> wrote: >> >> This patchset enables NKM clocks to consider alternative parent rates >> and utilize this new feature to adjust the pll-video0 clock on Allwinner >> A64. >> >> Furthermore, with this patchset pll-video0 considers rates that are >> higher than the requested rate when finding the closest rate. In >> consequence, higher rates are also considered by pll-video0's >> descandents. In total, after applying this patchset, finding the closest >> rate is supported by: >> - ccu_nm >> - ccu_nkm >> - ccu_mux >> - ccu_div >> >> This allows us to achieve an optimal rate for driving the board's panel. >> >> To provide some context, the clock structure involved in this process is >> as follows: >> clock clock type >> -------------------------------------- >> pll-video0 ccu_nm >> pll-mipi ccu_nkm >> tcon0 ccu_mux >> tcon-data-clock sun4i_dclk >> >> The divider between tcon0 and tcon-data-clock is fixed at 4. Therefore, >> in order to achieve a rate that closely matches the desired rate of the >> panel, pll-mipi needs to operate at a specific rate. >> >> Tests >> ===== >> So far, this has been successfully tested on the A64-based Pinephone >> using three different panel rates: >> >> 1. A panel rate that can be matched exactly by pll-video0. >> 2. A panel rate that requires pll-video0 to undershoot to get the >> closest rate. >> 3. A panel rate that requires pll-video0 to overshoot to get the >> closest rate. >> >> Test records: >> >> Re 1: >> ----- >> Panel requests tcon-data-clock of 103500000 Hz, i.e., pll-mipi needs to >> run at 414000000 Hz. This results in the following clock rates: >> clock rate >> ------------------------------------- >> pll-video0 207000000 >> hdmi-phy-clk 51750000 >> hdmi 207000000 >> tcon1 207000000 >> pll-mipi 414000000 >> tcon0 414000000 >> tcon-data-clock 103500000 >> >> The results of the find_best calls: >> ccu_nkm_find_best_with_parent_adj: rate=414000000, best_rate=414000000, best_parent_rate=207000000, n=1, k=2, m=1 >> ccu_nkm_find_best_with_parent_adj: rate=414000000, best_rate=414000000, best_parent_rate=207000000, n=1, k=2, m=1 >> ccu_nkm_find_best_with_parent_adj: rate=414000000, best_rate=414000000, best_parent_rate=207000000, n=1, k=2, m=1 >> ccu_nkm_find_best_with_parent_adj: rate=414000000, best_rate=414000000, best_parent_rate=207000000, n=1, k=2, m=1 >> ccu_nkm_find_best: rate=414000000, best_rate=414000000, parent_rate=207000000, n=1, k=2, m=1 >> >> Re 2: >> ----- >> Panel requests tcon-data-clock of 103650000 Hz, i.e., pll-mipi needs to >> run at 414600000 Hz. This results in the following clock rates: >> clock rate >> ------------------------------------- >> pll-video0 282666666 >> hdmi-phy-clk 70666666 >> hdmi 282666666 >> tcon1 282666666 >> pll-mipi 414577776 >> tcon0 414577776 >> tcon-data-clock 103644444 >> >> The results of the find_best calls: >> ccu_nkm_find_best_with_parent_adj: rate=414600000, best_rate=414577776, best_parent_rate=282666666, n=11, k=2, m=15 >> ccu_nkm_find_best_with_parent_adj: rate=414600000, best_rate=414577776, best_parent_rate=282666666, n=11, k=2, m=15 >> ccu_nkm_find_best_with_parent_adj: rate=414577776, best_rate=414577776, best_parent_rate=282666666, n=11, k=2, m=15 >> ccu_nkm_find_best_with_parent_adj: rate=414577776, best_rate=414577776, best_parent_rate=282666666, n=11, k=2, m=15 >> ccu_nkm_find_best: rate=414577776, best_rate=414577776, parent_rate=282666666, n=11, k=2, m=15 >> >> Re 3: >> ----- >> Panel requests tcon-data-clock of 112266000 Hz, i.e., pll-mipi needs to >> run at 449064000 Hz. This results in the following clock rates: >> clock rate >> ------------------------------------- >> pll-video0 207272727 >> hdmi-phy-clk 51818181 >> hdmi 207272727 >> tcon1 207272727 >> pll-mipi 449090908 >> tcon0 449090908 >> tcon-data-clock 112272727 >> >> The results of the find_best calls: >> ccu_nkm_find_best_with_parent_adj: rate=449064000, best_rate=449090908, best_parent_rate=207272727, n=13, k=2, m=12 >> ccu_nkm_find_best_with_parent_adj: rate=449064000, best_rate=449090908, best_parent_rate=207272727, n=13, k=2, m=12 >> ccu_nkm_find_best_with_parent_adj: rate=449090908, best_rate=449090908, best_parent_rate=207272727, n=13, k=2, m=12 >> ccu_nkm_find_best_with_parent_adj: rate=449090908, best_rate=449090908, best_parent_rate=207272727, n=13, k=2, m=12 >> ccu_nkm_find_best: rate=449090908, best_rate=449090908, parent_rate=207272727, n=13, k=2, m=12 >> >> Changelog: >> ---------- >> Changes in v6: >> - Removed unnecessary #include from ccu_nkm.c >> - Link to v5: https://lore.kernel.org/r/20230806-pll-mipi_set_rate_parent-v5-0-db4f5ca33fc3@oltmanns.dev >> >> Changes in v5: >> - Remove the dedicated function for calculating the optimal parent rate >> for nkm clocks that was introduced in v2 and again in v4. Instead use >> a simple calculation and require the parent clock to select the >> closest rate to achieve optimal results. >> - Change the order of parameters of nkm_best_rate and >> nkm_best_rate_with_parent_adj as requested my Maxime Ripard. >> - Prefer to not reset the rate of the nkm clock's parent if the ideal >> rate can be reached using the parent's current rate, copying the >> behavior of ccu_mp. >> - Link to v4: https://lore.kernel.org/r/20230717-pll-mipi_set_rate_parent-v4-0-04acf1d39765@oltmanns.dev >> >> Changes in v4: >> - Re-introduce a dedicated function for calculating the optimal parent >> rate for nkm clocks that was introduced in v2 and removed in v3. It >> turned out that not having this functionality introduces a bug when >> the parent does not support finding the closest rate: >> https://lore.kernel.org/all/87pm4xg2ub.fsf@oltmanns.dev/ >> - Incorporate review remarks: >> - Correcting the parameter name for ccu_nkm_round_rate()'s parent HW >> is now in a separate patch. >> - Use correct parameter order in ccu_nkm_find_best_with_parent_adj. >> - Add ccu_is_better_rate() and use it for determining the best rate >> for nm and nkm, as well as ccu_mux_helper_determine_rate. >> - Consistently introduce new macros for clock variants that support >> finding the closest rate instead of updating existing macros. >> - Use wrapper function for determining a ccu_mux's rate in order to >> support finding the closest rate. >> - Link to v3: https://lore.kernel.org/r/20230702-pll-mipi_set_rate_parent-v3-0-46dcb8aa9cbc@oltmanns.dev >> >> Changes in v3: >> - Use dedicated function for finding the best rate in cases where an >> nkm clock supports setting its parent's rate, streamlining it with >> the structure that is used in other sunxi-ng ccus such as ccu_mp >> (PATCH 1). >> - Therefore, remove the now obsolete comments that were introduced in >> v2 (PATCH 1). >> - Remove the dedicated function for calculating the optimal parent rate >> for nkm clocks that was introduced in v2. Instead use a simple >> calculation and require the parent clock to select the closest rate to >> achieve optimal results (PATCH 1). >> - Therefore, add support to set the closest rate for nm clocks (because >> pll-mipi's parent pll-video0 is an nm clock) and all clock types that >> are descendants of a64's pll-video0, i.e., nkm, mux, and div (PATCH 3 >> et. seq.). >> - Link to v2: https://lore.kernel.org/all/20230611090143.132257-1-frank@oltmanns.dev/ >> >> Changes in V2: >> - Move optimal parent rate calculation to dedicated function >> - Choose a parent rate that does not to overshoot requested rate >> - Add comments to ccu_nkm_find_best >> - Make sure that best_parent_rate stays at original parent rate in the unlikely >> case that all combinations overshoot. >> >> Link to V1: >> https://lore.kernel.org/lkml/20230605190745.366882-1-frank@oltmanns.dev/ >> >> --- >> Frank Oltmanns (11): >> clk: sunxi-ng: nkm: Use correct parameter name for parent HW >> clk: sunxi-ng: nkm: consider alternative parent rates when determining rate >> clk: sunxi-ng: a64: allow pll-mipi to set parent's rate >> clk: sunxi-ng: Add feature to find closest rate >> clk: sunxi-ng: Add helper function to find closest rate >> clk: sunxi-ng: nm: Support finding closest rate >> clk: sunxi-ng: nkm: Support finding closest rate >> clk: sunxi-ng: mux: Support finding closest rate >> clk: sunxi-ng: div: Support finding closest rate >> clk: sunxi-ng: a64: select closest rate for pll-video0 >> clk: sunxi-ng: nkm: Prefer current parent rate > > Whole series applied. There were some conflicts on patch 10 I had to > fix up. I also took the liberty of realigning some of the lines. > Please check if things are correct: > > https://git.kernel.org/pub/scm/linux/kernel/git/sunxi/linux.git/commit/?h=sunxi/clk-for-6.6&id=bf8eb12f52c49e10ca1d86564bfa096e09c51c38 > Thank you. I'm sorry, I used the wrong base-commit. Yours looks perfect! Also thank you for re-indenting. Looks cleaner. Best regards, Frank > > ChenYu > >> drivers/clk/sunxi-ng/ccu-sun50i-a64.c | 36 ++++++++++------------- >> drivers/clk/sunxi-ng/ccu_common.c | 12 ++++++++ >> drivers/clk/sunxi-ng/ccu_common.h | 6 ++++ >> drivers/clk/sunxi-ng/ccu_div.h | 30 +++++++++++++++++++ >> drivers/clk/sunxi-ng/ccu_mux.c | 15 ++++++++-- >> drivers/clk/sunxi-ng/ccu_mux.h | 38 +++++++++++++++++------- >> drivers/clk/sunxi-ng/ccu_nkm.c | 55 ++++++++++++++++++++++++++++++----- >> drivers/clk/sunxi-ng/ccu_nm.c | 13 ++++----- >> drivers/clk/sunxi-ng/ccu_nm.h | 48 ++++++++++++++++++++++++++++-- >> 9 files changed, 202 insertions(+), 51 deletions(-) >> --- >> base-commit: 6995e2de6891c724bfeb2db33d7b87775f913ad1 >> change-id: 20230626-pll-mipi_set_rate_parent-3363fc0d6e6f >> >> Best regards, >> -- >> Frank Oltmanns <frank@oltmanns.dev> >>
This patchset enables NKM clocks to consider alternative parent rates and utilize this new feature to adjust the pll-video0 clock on Allwinner A64. Furthermore, with this patchset pll-video0 considers rates that are higher than the requested rate when finding the closest rate. In consequence, higher rates are also considered by pll-video0's descandents. In total, after applying this patchset, finding the closest rate is supported by: - ccu_nm - ccu_nkm - ccu_mux - ccu_div This allows us to achieve an optimal rate for driving the board's panel. To provide some context, the clock structure involved in this process is as follows: clock clock type -------------------------------------- pll-video0 ccu_nm pll-mipi ccu_nkm tcon0 ccu_mux tcon-data-clock sun4i_dclk The divider between tcon0 and tcon-data-clock is fixed at 4. Therefore, in order to achieve a rate that closely matches the desired rate of the panel, pll-mipi needs to operate at a specific rate. Tests ===== So far, this has been successfully tested on the A64-based Pinephone using three different panel rates: 1. A panel rate that can be matched exactly by pll-video0. 2. A panel rate that requires pll-video0 to undershoot to get the closest rate. 3. A panel rate that requires pll-video0 to overshoot to get the closest rate. Test records: Re 1: ----- Panel requests tcon-data-clock of 103500000 Hz, i.e., pll-mipi needs to run at 414000000 Hz. This results in the following clock rates: clock rate ------------------------------------- pll-video0 207000000 hdmi-phy-clk 51750000 hdmi 207000000 tcon1 207000000 pll-mipi 414000000 tcon0 414000000 tcon-data-clock 103500000 The results of the find_best calls: ccu_nkm_find_best_with_parent_adj: rate=414000000, best_rate=414000000, best_parent_rate=207000000, n=1, k=2, m=1 ccu_nkm_find_best_with_parent_adj: rate=414000000, best_rate=414000000, best_parent_rate=207000000, n=1, k=2, m=1 ccu_nkm_find_best_with_parent_adj: rate=414000000, best_rate=414000000, best_parent_rate=207000000, n=1, k=2, m=1 ccu_nkm_find_best_with_parent_adj: rate=414000000, best_rate=414000000, best_parent_rate=207000000, n=1, k=2, m=1 ccu_nkm_find_best: rate=414000000, best_rate=414000000, parent_rate=207000000, n=1, k=2, m=1 Re 2: ----- Panel requests tcon-data-clock of 103650000 Hz, i.e., pll-mipi needs to run at 414600000 Hz. This results in the following clock rates: clock rate ------------------------------------- pll-video0 282666666 hdmi-phy-clk 70666666 hdmi 282666666 tcon1 282666666 pll-mipi 414577776 tcon0 414577776 tcon-data-clock 103644444 The results of the find_best calls: ccu_nkm_find_best_with_parent_adj: rate=414600000, best_rate=414577776, best_parent_rate=282666666, n=11, k=2, m=15 ccu_nkm_find_best_with_parent_adj: rate=414600000, best_rate=414577776, best_parent_rate=282666666, n=11, k=2, m=15 ccu_nkm_find_best_with_parent_adj: rate=414577776, best_rate=414577776, best_parent_rate=282666666, n=11, k=2, m=15 ccu_nkm_find_best_with_parent_adj: rate=414577776, best_rate=414577776, best_parent_rate=282666666, n=11, k=2, m=15 ccu_nkm_find_best: rate=414577776, best_rate=414577776, parent_rate=282666666, n=11, k=2, m=15 Re 3: ----- Panel requests tcon-data-clock of 112266000 Hz, i.e., pll-mipi needs to run at 449064000 Hz. This results in the following clock rates: clock rate ------------------------------------- pll-video0 207272727 hdmi-phy-clk 51818181 hdmi 207272727 tcon1 207272727 pll-mipi 449090908 tcon0 449090908 tcon-data-clock 112272727 The results of the find_best calls: ccu_nkm_find_best_with_parent_adj: rate=449064000, best_rate=449090908, best_parent_rate=207272727, n=13, k=2, m=12 ccu_nkm_find_best_with_parent_adj: rate=449064000, best_rate=449090908, best_parent_rate=207272727, n=13, k=2, m=12 ccu_nkm_find_best_with_parent_adj: rate=449090908, best_rate=449090908, best_parent_rate=207272727, n=13, k=2, m=12 ccu_nkm_find_best_with_parent_adj: rate=449090908, best_rate=449090908, best_parent_rate=207272727, n=13, k=2, m=12 ccu_nkm_find_best: rate=449090908, best_rate=449090908, parent_rate=207272727, n=13, k=2, m=12 Changelog: ---------- Changes in v6: - Removed unnecessary #include from ccu_nkm.c - Link to v5: https://lore.kernel.org/r/20230806-pll-mipi_set_rate_parent-v5-0-db4f5ca33fc3@oltmanns.dev Changes in v5: - Remove the dedicated function for calculating the optimal parent rate for nkm clocks that was introduced in v2 and again in v4. Instead use a simple calculation and require the parent clock to select the closest rate to achieve optimal results. - Change the order of parameters of nkm_best_rate and nkm_best_rate_with_parent_adj as requested my Maxime Ripard. - Prefer to not reset the rate of the nkm clock's parent if the ideal rate can be reached using the parent's current rate, copying the behavior of ccu_mp. - Link to v4: https://lore.kernel.org/r/20230717-pll-mipi_set_rate_parent-v4-0-04acf1d39765@oltmanns.dev Changes in v4: - Re-introduce a dedicated function for calculating the optimal parent rate for nkm clocks that was introduced in v2 and removed in v3. It turned out that not having this functionality introduces a bug when the parent does not support finding the closest rate: https://lore.kernel.org/all/87pm4xg2ub.fsf@oltmanns.dev/ - Incorporate review remarks: - Correcting the parameter name for ccu_nkm_round_rate()'s parent HW is now in a separate patch. - Use correct parameter order in ccu_nkm_find_best_with_parent_adj. - Add ccu_is_better_rate() and use it for determining the best rate for nm and nkm, as well as ccu_mux_helper_determine_rate. - Consistently introduce new macros for clock variants that support finding the closest rate instead of updating existing macros. - Use wrapper function for determining a ccu_mux's rate in order to support finding the closest rate. - Link to v3: https://lore.kernel.org/r/20230702-pll-mipi_set_rate_parent-v3-0-46dcb8aa9cbc@oltmanns.dev Changes in v3: - Use dedicated function for finding the best rate in cases where an nkm clock supports setting its parent's rate, streamlining it with the structure that is used in other sunxi-ng ccus such as ccu_mp (PATCH 1). - Therefore, remove the now obsolete comments that were introduced in v2 (PATCH 1). - Remove the dedicated function for calculating the optimal parent rate for nkm clocks that was introduced in v2. Instead use a simple calculation and require the parent clock to select the closest rate to achieve optimal results (PATCH 1). - Therefore, add support to set the closest rate for nm clocks (because pll-mipi's parent pll-video0 is an nm clock) and all clock types that are descendants of a64's pll-video0, i.e., nkm, mux, and div (PATCH 3 et. seq.). - Link to v2: https://lore.kernel.org/all/20230611090143.132257-1-frank@oltmanns.dev/ Changes in V2: - Move optimal parent rate calculation to dedicated function - Choose a parent rate that does not to overshoot requested rate - Add comments to ccu_nkm_find_best - Make sure that best_parent_rate stays at original parent rate in the unlikely case that all combinations overshoot. Link to V1: https://lore.kernel.org/lkml/20230605190745.366882-1-frank@oltmanns.dev/ --- Frank Oltmanns (11): clk: sunxi-ng: nkm: Use correct parameter name for parent HW clk: sunxi-ng: nkm: consider alternative parent rates when determining rate clk: sunxi-ng: a64: allow pll-mipi to set parent's rate clk: sunxi-ng: Add feature to find closest rate clk: sunxi-ng: Add helper function to find closest rate clk: sunxi-ng: nm: Support finding closest rate clk: sunxi-ng: nkm: Support finding closest rate clk: sunxi-ng: mux: Support finding closest rate clk: sunxi-ng: div: Support finding closest rate clk: sunxi-ng: a64: select closest rate for pll-video0 clk: sunxi-ng: nkm: Prefer current parent rate drivers/clk/sunxi-ng/ccu-sun50i-a64.c | 36 ++++++++++------------- drivers/clk/sunxi-ng/ccu_common.c | 12 ++++++++ drivers/clk/sunxi-ng/ccu_common.h | 6 ++++ drivers/clk/sunxi-ng/ccu_div.h | 30 +++++++++++++++++++ drivers/clk/sunxi-ng/ccu_mux.c | 15 ++++++++-- drivers/clk/sunxi-ng/ccu_mux.h | 38 +++++++++++++++++------- drivers/clk/sunxi-ng/ccu_nkm.c | 55 ++++++++++++++++++++++++++++++----- drivers/clk/sunxi-ng/ccu_nm.c | 13 ++++----- drivers/clk/sunxi-ng/ccu_nm.h | 48 ++++++++++++++++++++++++++++-- 9 files changed, 202 insertions(+), 51 deletions(-) --- base-commit: 6995e2de6891c724bfeb2db33d7b87775f913ad1 change-id: 20230626-pll-mipi_set_rate_parent-3363fc0d6e6f Best regards,