On Mon, Oct 30, 2017 at 5:12 PM, Marek Vasut <ma...@denx.de> wrote: > On 10/30/2017 12:36 PM, Jagan Teki wrote: >> On Mon, Oct 30, 2017 at 4:24 PM, Marek Vasut <ma...@denx.de> wrote: >>> On 10/30/2017 07:04 AM, Jagan Teki wrote: >>>> On Sat, Oct 28, 2017 at 5:09 PM, Marek Vasut <ma...@denx.de> wrote: >>>>> On 10/27/2017 03:54 PM, Eugeniy Paltsev wrote: >>>>>> On Tue, 2017-10-24 at 15:22 +0530, Jagan Teki wrote: >>>>>>> On Tue, Oct 24, 2017 at 11:38 AM, Marek Vasut <ma...@denx.de> wrote: >>>>>>>> On 10/23/2017 01:43 PM, Eugeniy Paltsev wrote: >>>>>>>>> On Thu, 2017-10-19 at 13:20 -0500, Dinh Nguyen wrote: >>>>>>>>>> >>>>>>>>>> On 10/19/2017 10:51 AM, Marek Vasut wrote: >>>>>>>>>>> On 10/19/2017 05:36 PM, Eugeniy Paltsev wrote: >>>>>>>>>>>> On Tue, 2017-10-17 at 20:32 +0530, Jagan Teki wrote: >>>>>>>>>>>>> On Tue, Oct 17, 2017 at 8:27 PM, Alexey Brodkin >>>>>>>>>>>>> <alexey.brod...@synopsys.com> wrote: >>>>>>>>>>>>>> Hi Jagan, >>>>>>>>>>>>>> >>>>>>>>>>>>>>> -----Original Message----- >>>>>>>>>>>>>>> From: Eugeniy Paltsev [mailto:palt...@synopsys.com] >>>>>>>>>>>>>>> Sent: Tuesday, October 17, 2017 4:33 PM >>>>>>>>>>>>>>> To: jagannadh.t...@gmail.com >>>>>>>>>>>>>>> Cc: u-boot@lists.denx.de; uboot-snps-...@synopsys.com >>>>>>>>>>>>>>> Subject: [uboot-snps-arc] Re: [PATCH v2] DW SPI: Get clock >>>>>>>>>>>>>>> value from Device Tree >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> How hard it is to make others to use clock manager? do you >>>>>>>>>>>>>>>> have any list? >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> clock_manager.h is an old (and non-generic) way to deal with >>>>>>>>>>>>>>> different clocks. >>>>>>>>>>>>>>> For example in SOCFPGA_GEN5 and SOCFPGA_ARRIA10 clock_manager.h >>>>>>>>>>>>>>> provides >>>>>>>>>>>>>>> cm_get_spi_controller_clk_hz function to deal with spi >>>>>>>>>>>>>>> controller clock. >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> But today we have another, linux-like alternative: to bind >>>>>>>>>>>>>>> clocks via device tree >>>>>>>>>>>>>>> and manipulate with clocks via generic functions provided by >>>>>>>>>>>>>>> clk.h >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> In this patch I added option to get clock via device tree using >>>>>>>>>>>>>>> standard bindings >>>>>>>>>>>>>>> and restrict clock_manager.h functions usage only to targets >>>>>>>>>>>>>>> which still use it, >>>>>>>>>>>>>>> so new targets can simply bind clock via device tree and they >>>>>>>>>>>>>>> do not need to >>>>>>>>>>>>>>> implement/define something in clock_manager.h >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> So we don't need to make others to use clock manager :) >>>>>>>>>>>>>> >>>>>>>>>>>>>> Maybe it worth trying the other way around and think about >>>>>>>>>>>>>> switching SOCFPGA platforms to >>>>>>>>>>>>>> generic clk framework? >>>>>>>>>>>>> >>>>>>>>>>>>> Yes, ie what exactly I thought of, thanks! >>>>>>>>>>>> >>>>>>>>>>>> I checked cm_get_spi_controller_clk_hz implementation in >>>>>>>>>>>> SOCFPGA_GEN5 and >>>>>>>>>>>> SOCFPGA_ARRIA10: we can't simply replace it with "fixed-clock" >>>>>>>>>>>> driver as it >>>>>>>>>>>> manipulate with real hardware. >>>>>>>>>>>> The only way to do it is to replace SOCFPGA* clock manager >>>>>>>>>>>> functions by real >>>>>>>>>>>> clock driver. >>>>>>>>>>>> >>>>>>>>>>>> And given I don't have mentioned hardware so I barely can help with >>>>>>>>>>>> those improvements on SOCFPGA. That said if there're no short-term >>>>>>>>>>>> plans to >>>>>>>>>>>> switch SOCFPGA to clk framework maybe we'll be OK with my >>>>>>>>>>>> workaround with #ifdefs? >>>>>>>>>>> >>>>>>>>>>> Wait for Dinh's reply ... >>>>>>>>>>> >>>>>>>>>> >>>>>>>>>> Honestly, I don't have too much time to work on this right now. So I >>>>>>>>>> really don't when it can get done. But it'll go on my to-do list. >>>>>>>>>> >>>>>>>>>> Dinh >>>>>>>>> >>>>>>>>> Yep, thanks for your comments. >>>>>>>>> >>>>>>>>> So, Jagan, >>>>>>>>> given Dinh's reply, could you please apply this patch? >>>>>>>> >>>>>>>> I'd really hate it to start seeing soc-specific ifdefs in drivers, >>>>>>>> that's IMO not acceptable. A __weak override might be a temporary >>>>>>>> solution I'd be willing to live with though. >>>>>>> >>>>>>> I would rather like to see some check on clock manager itself whether >>>>>>> CONFIG_IS_ENABLED(CLK) is using or not? this can tends not to use >>>>>>> __weak as well soc #ifdefs in driver. >>>>>>> >>>>>> >>>>>> Actually I don't understand what do you mean. >>>>>> Even if I add any #ifdefs to the clock_manager.h I still need to wrap >>>>>> clock_manager.h >>>>>> include with #ifdefs as clock_manager.h is defined only for two >>>>>> targets - SOCFPGA_GEN5 and SOCFPGA_ARRIA10. >>>>>> >>>>>> #if defined(CONFIG_TARGET_SOCFPGA_GEN5) || >>>>>> defined(CONFIG_TARGET_SOCFPGA_ARRIA10) >>>>>> #include <asm/arch/clock_manager.h> >>>>>> #endif >>>>>> >>>>>> And I think it is better to add this #ifdef in driver than create empty >>>>>> clock_manager.h file for every new target which uses this driver. >>>> >>>> Check CLK in clock-manager like below, of-course cm_get_l4_noc_hz used >>>> in other IP's as well. we need to carefully adding these check and if >>>> require add CLK for remaining drivers as well. the reason for adding >>>> checks in clock-manager is it may be removable code if all use CLK. >>> >>> I do not understand what you're trying to tell me, but the patch below >>> makes no sense. What I would like to see is a weak function in the >>> driver and that function be overriden in the socfpga clock manager. >> >> I'm trying to avoid __weak or #ifdef on driver instead make changes in >> clock manager which will remove in future(once all moved with CLK) > > Well, if you do the proposed change, socfpga will break. The __weak is > the least possible evil here and I can live with that for now.
Yes, __weak can be possible evil here but since I'm planning to apply this in next version, I'm hoping possible change that shouldn't effect the driver. I see some __weak's last from many releases that doesn't resolve properly and they are still __weak functions only. thanks! -- Jagan Teki Free Software Engineer | www.openedev.com U-Boot, Linux | Upstream Maintainer Hyderabad, India. _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot
