* [PATCH 1/2] arm64: change ARCH_SPRD Kconfig to tristate @ 2020-03-05 10:32 Chunyan Zhang 2020-03-05 10:32 ` [PATCH 2/2] tty: serial: make SERIAL_SPRD not depend on ARCH_SPRD Chunyan Zhang 2020-03-09 8:03 ` [PATCH 1/2] arm64: change ARCH_SPRD Kconfig to tristate Geert Uytterhoeven 0 siblings, 2 replies; 18+ messages in thread From: Chunyan Zhang @ 2020-03-05 10:32 UTC (permalink / raw) To: Greg Kroah-Hartman, Catalin Marinas, Will Deacon, Jiri Slaby Cc: Chunyan Zhang, linux-kernel, Chunyan Zhang, linux-serial, Baolin Wang, Orson Zhai, linux-arm-kernel From: Chunyan Zhang <chunyan.zhang@unisoc.com> The default value of Kconfig for almost all sprd drivers are the same with ARCH_SPRD, making these drivers built as modules as default would be easier if we can set ARCH_SPRD as 'm', so this patch change ARCH_SPRD to tristate. Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com> --- arch/arm64/Kconfig.platforms | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm64/Kconfig.platforms b/arch/arm64/Kconfig.platforms index b2b504ea6fd6..76778b2f520d 100644 --- a/arch/arm64/Kconfig.platforms +++ b/arch/arm64/Kconfig.platforms @@ -249,7 +249,7 @@ config ARCH_TEGRA This enables support for the NVIDIA Tegra SoC family. config ARCH_SPRD - bool "Spreadtrum SoC platform" + tristate "Spreadtrum SoC platform" help Support for Spreadtrum ARM based SoCs -- 2.20.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply related [flat|nested] 18+ messages in thread
* [PATCH 2/2] tty: serial: make SERIAL_SPRD not depend on ARCH_SPRD 2020-03-05 10:32 [PATCH 1/2] arm64: change ARCH_SPRD Kconfig to tristate Chunyan Zhang @ 2020-03-05 10:32 ` Chunyan Zhang 2020-03-06 12:41 ` Geert Uytterhoeven 2020-03-09 8:03 ` [PATCH 1/2] arm64: change ARCH_SPRD Kconfig to tristate Geert Uytterhoeven 1 sibling, 1 reply; 18+ messages in thread From: Chunyan Zhang @ 2020-03-05 10:32 UTC (permalink / raw) To: Greg Kroah-Hartman, Catalin Marinas, Will Deacon, Jiri Slaby Cc: Chunyan Zhang, linux-kernel, Chunyan Zhang, linux-serial, Baolin Wang, Orson Zhai, linux-arm-kernel From: Chunyan Zhang <chunyan.zhang@unisoc.com> Remove the dependency with ARCH_SPRD from sprd serial/console Kconfig-s, since we want them can be built-in when ARCH_SPRD is set as 'm'. Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com> --- drivers/tty/serial/Kconfig | 1 - 1 file changed, 1 deletion(-) diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig index 52eaac21ff9f..2b9addc0afb5 100644 --- a/drivers/tty/serial/Kconfig +++ b/drivers/tty/serial/Kconfig @@ -1452,7 +1452,6 @@ config SERIAL_MEN_Z135 config SERIAL_SPRD tristate "Support for Spreadtrum serial" - depends on ARCH_SPRD select SERIAL_CORE help This enables the driver for the Spreadtrum's serial. -- 2.20.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply related [flat|nested] 18+ messages in thread
* Re: [PATCH 2/2] tty: serial: make SERIAL_SPRD not depend on ARCH_SPRD 2020-03-05 10:32 ` [PATCH 2/2] tty: serial: make SERIAL_SPRD not depend on ARCH_SPRD Chunyan Zhang @ 2020-03-06 12:41 ` Geert Uytterhoeven 2020-03-09 1:17 ` Chunyan Zhang 0 siblings, 1 reply; 18+ messages in thread From: Geert Uytterhoeven @ 2020-03-06 12:41 UTC (permalink / raw) To: Chunyan Zhang Cc: Catalin Marinas, Greg Kroah-Hartman, Linux Kernel Mailing List, Chunyan Zhang, open list:SERIAL DRIVERS, Jiri Slaby, Baolin Wang, Orson Zhai, Will Deacon, Linux ARM Hi Chunyan, On Thu, Mar 5, 2020 at 11:33 AM Chunyan Zhang <zhang.lyra@gmail.com> wrote: > From: Chunyan Zhang <chunyan.zhang@unisoc.com> > > Remove the dependency with ARCH_SPRD from sprd serial/console Kconfig-s, > since we want them can be built-in when ARCH_SPRD is set as 'm'. Why would you want a serial driver for a specific platform to be builtin, while all other platform support is modular? > Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com> > --- > drivers/tty/serial/Kconfig | 1 - > 1 file changed, 1 deletion(-) > > diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig > index 52eaac21ff9f..2b9addc0afb5 100644 > --- a/drivers/tty/serial/Kconfig > +++ b/drivers/tty/serial/Kconfig > @@ -1452,7 +1452,6 @@ config SERIAL_MEN_Z135 > > config SERIAL_SPRD > tristate "Support for Spreadtrum serial" > - depends on ARCH_SPRD > select SERIAL_CORE > help > This enables the driver for the Spreadtrum's serial. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH 2/2] tty: serial: make SERIAL_SPRD not depend on ARCH_SPRD 2020-03-06 12:41 ` Geert Uytterhoeven @ 2020-03-09 1:17 ` Chunyan Zhang 2020-03-09 8:01 ` Geert Uytterhoeven 0 siblings, 1 reply; 18+ messages in thread From: Chunyan Zhang @ 2020-03-09 1:17 UTC (permalink / raw) To: Geert Uytterhoeven Cc: Catalin Marinas, Greg Kroah-Hartman, Linux Kernel Mailing List, Chunyan Zhang, open list:SERIAL DRIVERS, Jiri Slaby, Baolin Wang, Orson Zhai, Will Deacon, Linux ARM Hi Geert, On Fri, 6 Mar 2020 at 20:41, Geert Uytterhoeven <geert@linux-m68k.org> wrote: > > Hi Chunyan, > > On Thu, Mar 5, 2020 at 11:33 AM Chunyan Zhang <zhang.lyra@gmail.com> wrote: > > From: Chunyan Zhang <chunyan.zhang@unisoc.com> > > > > Remove the dependency with ARCH_SPRD from sprd serial/console Kconfig-s, > > since we want them can be built-in when ARCH_SPRD is set as 'm'. > > Why would you want a serial driver for a specific platform to be builtin, > while all other platform support is modular? Oh, that's not this patch means. We just want serial driver can be builtin for any platform, so it should not depend on a config which can be set as 'm' (i.e. ARCH_SPRD) , otherwise if the config was set as 'm', the serial driver can't be selected as 'y' then. That's what I mean. Cheers, Chunyan > > > Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com> > > --- > > drivers/tty/serial/Kconfig | 1 - > > 1 file changed, 1 deletion(-) > > > > diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig > > index 52eaac21ff9f..2b9addc0afb5 100644 > > --- a/drivers/tty/serial/Kconfig > > +++ b/drivers/tty/serial/Kconfig > > @@ -1452,7 +1452,6 @@ config SERIAL_MEN_Z135 > > > > config SERIAL_SPRD > > tristate "Support for Spreadtrum serial" > > - depends on ARCH_SPRD > > select SERIAL_CORE > > help > > This enables the driver for the Spreadtrum's serial. > > Gr{oetje,eeting}s, > > Geert > > -- > Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org > > In personal conversations with technical people, I call myself a hacker. But > when I'm talking to journalists I just say "programmer" or something like that. > -- Linus Torvalds _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH 2/2] tty: serial: make SERIAL_SPRD not depend on ARCH_SPRD 2020-03-09 1:17 ` Chunyan Zhang @ 2020-03-09 8:01 ` Geert Uytterhoeven 2020-03-09 8:42 ` Chunyan Zhang 2020-03-09 14:10 ` Orson Zhai 0 siblings, 2 replies; 18+ messages in thread From: Geert Uytterhoeven @ 2020-03-09 8:01 UTC (permalink / raw) To: Chunyan Zhang Cc: Catalin Marinas, Greg Kroah-Hartman, Linux Kernel Mailing List, Chunyan Zhang, open list:SERIAL DRIVERS, Jiri Slaby, Baolin Wang, Orson Zhai, Will Deacon, Linux ARM Hi Chunyan, On Mon, Mar 9, 2020 at 2:18 AM Chunyan Zhang <zhang.lyra@gmail.com> wrote: > On Fri, 6 Mar 2020 at 20:41, Geert Uytterhoeven <geert@linux-m68k.org> wrote: > > On Thu, Mar 5, 2020 at 11:33 AM Chunyan Zhang <zhang.lyra@gmail.com> wrote: > > > From: Chunyan Zhang <chunyan.zhang@unisoc.com> > > > > > > Remove the dependency with ARCH_SPRD from sprd serial/console Kconfig-s, > > > since we want them can be built-in when ARCH_SPRD is set as 'm'. > > > > Why would you want a serial driver for a specific platform to be builtin, > > while all other platform support is modular? > > Oh, that's not this patch means. > > We just want serial driver can be builtin for any platform, so it What would be the benefit of the user to be able to have the SPRD serial driver built-in on any platform? AFAIU, it supports only Spreadtrum platforms. > should not depend on a config which can be set as 'm' (i.e. ARCH_SPRD) > , otherwise if the config was set as 'm', the serial driver can't be > selected as 'y' then. I ask about that as a reply to PATCH 1/2. > That's what I mean. > > > --- a/drivers/tty/serial/Kconfig > > > +++ b/drivers/tty/serial/Kconfig > > > @@ -1452,7 +1452,6 @@ config SERIAL_MEN_Z135 > > > > > > config SERIAL_SPRD > > > tristate "Support for Spreadtrum serial" > > > - depends on ARCH_SPRD > > > select SERIAL_CORE > > > help > > > This enables the driver for the Spreadtrum's serial. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH 2/2] tty: serial: make SERIAL_SPRD not depend on ARCH_SPRD 2020-03-09 8:01 ` Geert Uytterhoeven @ 2020-03-09 8:42 ` Chunyan Zhang 2020-03-09 10:32 ` Geert Uytterhoeven 2020-03-09 14:10 ` Orson Zhai 1 sibling, 1 reply; 18+ messages in thread From: Chunyan Zhang @ 2020-03-09 8:42 UTC (permalink / raw) To: Geert Uytterhoeven Cc: Catalin Marinas, Greg Kroah-Hartman, Linux Kernel Mailing List, Chunyan Zhang, open list:SERIAL DRIVERS, Jiri Slaby, Baolin Wang, Orson Zhai, Will Deacon, Linux ARM Hi Geert, On Mon, 9 Mar 2020 at 16:01, Geert Uytterhoeven <geert@linux-m68k.org> wrote: > > Hi Chunyan, > > On Mon, Mar 9, 2020 at 2:18 AM Chunyan Zhang <zhang.lyra@gmail.com> wrote: > > On Fri, 6 Mar 2020 at 20:41, Geert Uytterhoeven <geert@linux-m68k.org> wrote: > > > On Thu, Mar 5, 2020 at 11:33 AM Chunyan Zhang <zhang.lyra@gmail.com> wrote: > > > > From: Chunyan Zhang <chunyan.zhang@unisoc.com> > > > > > > > > Remove the dependency with ARCH_SPRD from sprd serial/console Kconfig-s, > > > > since we want them can be built-in when ARCH_SPRD is set as 'm'. > > > > > > Why would you want a serial driver for a specific platform to be builtin, > > > while all other platform support is modular? > > > > Oh, that's not this patch means. > > > > We just want serial driver can be builtin for any platform, so it > > What would be the benefit of the user to be able to have the SPRD serial > driver built-in on any platform? AFAIU, it supports only Spreadtrum > platforms. Right, it does support Spreadtrum platforms only indeed. Like I said on the replay to patch 1/2, simply because I want serial driver can be builtin all the time, no matter ARCH_SPRD is m or y. Regards, Chunyan > > > should not depend on a config which can be set as 'm' (i.e. ARCH_SPRD) > > , otherwise if the config was set as 'm', the serial driver can't be > > selected as 'y' then. > > I ask about that as a reply to PATCH 1/2. > > > That's what I mean. > > > > > --- a/drivers/tty/serial/Kconfig > > > > +++ b/drivers/tty/serial/Kconfig > > > > @@ -1452,7 +1452,6 @@ config SERIAL_MEN_Z135 > > > > > > > > config SERIAL_SPRD > > > > tristate "Support for Spreadtrum serial" > > > > - depends on ARCH_SPRD > > > > select SERIAL_CORE > > > > help > > > > This enables the driver for the Spreadtrum's serial. > > Gr{oetje,eeting}s, > > Geert > > -- > Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org > > In personal conversations with technical people, I call myself a hacker. But > when I'm talking to journalists I just say "programmer" or something like that. > -- Linus Torvalds _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH 2/2] tty: serial: make SERIAL_SPRD not depend on ARCH_SPRD 2020-03-09 8:42 ` Chunyan Zhang @ 2020-03-09 10:32 ` Geert Uytterhoeven 2020-03-09 11:15 ` Chunyan Zhang 0 siblings, 1 reply; 18+ messages in thread From: Geert Uytterhoeven @ 2020-03-09 10:32 UTC (permalink / raw) To: Chunyan Zhang Cc: Catalin Marinas, Greg Kroah-Hartman, Linux Kernel Mailing List, Chunyan Zhang, open list:SERIAL DRIVERS, Jiri Slaby, Baolin Wang, Orson Zhai, Will Deacon, Linux ARM Hi Chunyan, On Mon, Mar 9, 2020 at 9:43 AM Chunyan Zhang <zhang.lyra@gmail.com> wrote: > On Mon, 9 Mar 2020 at 16:01, Geert Uytterhoeven <geert@linux-m68k.org> wrote: > > On Mon, Mar 9, 2020 at 2:18 AM Chunyan Zhang <zhang.lyra@gmail.com> wrote: > > > On Fri, 6 Mar 2020 at 20:41, Geert Uytterhoeven <geert@linux-m68k.org> wrote: > > > > On Thu, Mar 5, 2020 at 11:33 AM Chunyan Zhang <zhang.lyra@gmail.com> wrote: > > > > > From: Chunyan Zhang <chunyan.zhang@unisoc.com> > > > > > > > > > > Remove the dependency with ARCH_SPRD from sprd serial/console Kconfig-s, > > > > > since we want them can be built-in when ARCH_SPRD is set as 'm'. > > > > > > > > Why would you want a serial driver for a specific platform to be builtin, > > > > while all other platform support is modular? > > > > > > Oh, that's not this patch means. > > > > > > We just want serial driver can be builtin for any platform, so it > > > > What would be the benefit of the user to be able to have the SPRD serial > > driver built-in on any platform? AFAIU, it supports only Spreadtrum > > platforms. > > Right, it does support Spreadtrum platforms only indeed. > Like I said on the replay to patch 1/2, simply because I want serial > driver can be builtin all the time, no matter ARCH_SPRD is m or y. OK. So shouldn't the dependency become depends on ARCH_SPRD || ARCH_SPRD=m || COMPILE_TEST instead, to avoid asking the question when you're not building a kernel plus modules for Spreadtrum platforms? > > > should not depend on a config which can be set as 'm' (i.e. ARCH_SPRD) > > > , otherwise if the config was set as 'm', the serial driver can't be > > > selected as 'y' then. > > > > I ask about that as a reply to PATCH 1/2. > > > > > That's what I mean. > > > > > > > --- a/drivers/tty/serial/Kconfig > > > > > +++ b/drivers/tty/serial/Kconfig > > > > > @@ -1452,7 +1452,6 @@ config SERIAL_MEN_Z135 > > > > > > > > > > config SERIAL_SPRD > > > > > tristate "Support for Spreadtrum serial" > > > > > - depends on ARCH_SPRD > > > > > select SERIAL_CORE > > > > > help > > > > > This enables the driver for the Spreadtrum's serial. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH 2/2] tty: serial: make SERIAL_SPRD not depend on ARCH_SPRD 2020-03-09 10:32 ` Geert Uytterhoeven @ 2020-03-09 11:15 ` Chunyan Zhang 0 siblings, 0 replies; 18+ messages in thread From: Chunyan Zhang @ 2020-03-09 11:15 UTC (permalink / raw) To: Geert Uytterhoeven Cc: Catalin Marinas, Greg Kroah-Hartman, Linux Kernel Mailing List, Chunyan Zhang, open list:SERIAL DRIVERS, Jiri Slaby, Baolin Wang, Orson Zhai, Will Deacon, Linux ARM On Mon, 9 Mar 2020 at 18:32, Geert Uytterhoeven <geert@linux-m68k.org> wrote: > > Hi Chunyan, > > On Mon, Mar 9, 2020 at 9:43 AM Chunyan Zhang <zhang.lyra@gmail.com> wrote: > > On Mon, 9 Mar 2020 at 16:01, Geert Uytterhoeven <geert@linux-m68k.org> wrote: > > > On Mon, Mar 9, 2020 at 2:18 AM Chunyan Zhang <zhang.lyra@gmail.com> wrote: > > > > On Fri, 6 Mar 2020 at 20:41, Geert Uytterhoeven <geert@linux-m68k.org> wrote: > > > > > On Thu, Mar 5, 2020 at 11:33 AM Chunyan Zhang <zhang.lyra@gmail.com> wrote: > > > > > > From: Chunyan Zhang <chunyan.zhang@unisoc.com> > > > > > > > > > > > > Remove the dependency with ARCH_SPRD from sprd serial/console Kconfig-s, > > > > > > since we want them can be built-in when ARCH_SPRD is set as 'm'. > > > > > > > > > > Why would you want a serial driver for a specific platform to be builtin, > > > > > while all other platform support is modular? > > > > > > > > Oh, that's not this patch means. > > > > > > > > We just want serial driver can be builtin for any platform, so it > > > > > > What would be the benefit of the user to be able to have the SPRD serial > > > driver built-in on any platform? AFAIU, it supports only Spreadtrum > > > platforms. > > > > Right, it does support Spreadtrum platforms only indeed. > > Like I said on the replay to patch 1/2, simply because I want serial > > driver can be builtin all the time, no matter ARCH_SPRD is m or y. > > OK. > > So shouldn't the dependency become > > depends on ARCH_SPRD || ARCH_SPRD=m || COMPILE_TEST Oh, right, this's better than just removing dependency to ARCH_SPRD, but considering that this patch has been merged into Greg's tree, I will post another patch to add this. Thanks for your comments! Chunyan > > instead, to avoid asking the question when you're not building a kernel > plus modules for Spreadtrum platforms? > > > > > > should not depend on a config which can be set as 'm' (i.e. ARCH_SPRD) > > > > , otherwise if the config was set as 'm', the serial driver can't be > > > > selected as 'y' then. > > > > > > I ask about that as a reply to PATCH 1/2. > > > > > > > That's what I mean. > > > > > > > > > --- a/drivers/tty/serial/Kconfig > > > > > > +++ b/drivers/tty/serial/Kconfig > > > > > > @@ -1452,7 +1452,6 @@ config SERIAL_MEN_Z135 > > > > > > > > > > > > config SERIAL_SPRD > > > > > > tristate "Support for Spreadtrum serial" > > > > > > - depends on ARCH_SPRD > > > > > > select SERIAL_CORE > > > > > > help > > > > > > This enables the driver for the Spreadtrum's serial. > > Gr{oetje,eeting}s, > > Geert > > -- > Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org > > In personal conversations with technical people, I call myself a hacker. But > when I'm talking to journalists I just say "programmer" or something like that. > -- Linus Torvalds _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH 2/2] tty: serial: make SERIAL_SPRD not depend on ARCH_SPRD 2020-03-09 8:01 ` Geert Uytterhoeven 2020-03-09 8:42 ` Chunyan Zhang @ 2020-03-09 14:10 ` Orson Zhai 1 sibling, 0 replies; 18+ messages in thread From: Orson Zhai @ 2020-03-09 14:10 UTC (permalink / raw) To: Geert Uytterhoeven Cc: kernel-team, Catalin Marinas, Greg Kroah-Hartman, Chunyan Zhang, Linux Kernel Mailing List, Chunyan Zhang, open list:SERIAL DRIVERS, Jiri Slaby, Baolin Wang, Will Deacon, Linux ARM Hi Geert, On Mon, Mar 9, 2020 at 4:01 PM Geert Uytterhoeven <geert@linux-m68k.org> wrote: > > Hi Chunyan, > > On Mon, Mar 9, 2020 at 2:18 AM Chunyan Zhang <zhang.lyra@gmail.com> wrote: > > On Fri, 6 Mar 2020 at 20:41, Geert Uytterhoeven <geert@linux-m68k.org> wrote: > > > On Thu, Mar 5, 2020 at 11:33 AM Chunyan Zhang <zhang.lyra@gmail.com> wrote: > > > > From: Chunyan Zhang <chunyan.zhang@unisoc.com> > > > > > > > > Remove the dependency with ARCH_SPRD from sprd serial/console Kconfig-s, > > > > since we want them can be built-in when ARCH_SPRD is set as 'm'. > > > > > > Why would you want a serial driver for a specific platform to be builtin, > > > while all other platform support is modular? > > > > Oh, that's not this patch means. > > > > We just want serial driver can be builtin for any platform, so it > > What would be the benefit of the user to be able to have the SPRD serial > driver built-in on any platform? AFAIU, it supports only Spreadtrum > platforms. > Assume there is a all-in-one common kernel binary image say arm64 for all SoC platform and all device drivers are built as modules from different vendors for each specific devices. But for serial driver it is too late to be initialized as a module if users want to check early console log. At this circumstance vendors prefer to set their serial driver to be built into that all-in-one image as easy as to only set one config instead of enabling whole platform then disabling many out of serial. -Orson > > should not depend on a config which can be set as 'm' (i.e. ARCH_SPRD) > > , otherwise if the config was set as 'm', the serial driver can't be > > selected as 'y' then. > > I ask about that as a reply to PATCH 1/2. > > > That's what I mean. > > > > > --- a/drivers/tty/serial/Kconfig > > > > +++ b/drivers/tty/serial/Kconfig > > > > @@ -1452,7 +1452,6 @@ config SERIAL_MEN_Z135 > > > > > > > > config SERIAL_SPRD > > > > tristate "Support for Spreadtrum serial" > > > > - depends on ARCH_SPRD > > > > select SERIAL_CORE > > > > help > > > > This enables the driver for the Spreadtrum's serial. > > Gr{oetje,eeting}s, > > Geert > > -- > Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org > > In personal conversations with technical people, I call myself a hacker. But > when I'm talking to journalists I just say "programmer" or something like that. > -- Linus Torvalds _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH 1/2] arm64: change ARCH_SPRD Kconfig to tristate 2020-03-05 10:32 [PATCH 1/2] arm64: change ARCH_SPRD Kconfig to tristate Chunyan Zhang 2020-03-05 10:32 ` [PATCH 2/2] tty: serial: make SERIAL_SPRD not depend on ARCH_SPRD Chunyan Zhang @ 2020-03-09 8:03 ` Geert Uytterhoeven 2020-03-09 8:32 ` Chunyan Zhang 1 sibling, 1 reply; 18+ messages in thread From: Geert Uytterhoeven @ 2020-03-09 8:03 UTC (permalink / raw) To: Chunyan Zhang Cc: Catalin Marinas, Greg Kroah-Hartman, Linux Kernel Mailing List, Chunyan Zhang, open list:SERIAL DRIVERS, Jiri Slaby, Baolin Wang, Orson Zhai, Will Deacon, Linux ARM Hi Chunyan. On Thu, Mar 5, 2020 at 11:33 AM Chunyan Zhang <zhang.lyra@gmail.com> wrote: > From: Chunyan Zhang <chunyan.zhang@unisoc.com> > > The default value of Kconfig for almost all sprd drivers are the same with > ARCH_SPRD, making these drivers built as modules as default would be easier > if we can set ARCH_SPRD as 'm', so this patch change ARCH_SPRD to tristate. > > Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com> Can you actually boot a kernel on a Spreadtrum platform when all platform and driver support is modular? > +++ b/arch/arm64/Kconfig.platforms > @@ -249,7 +249,7 @@ config ARCH_TEGRA > This enables support for the NVIDIA Tegra SoC family. > > config ARCH_SPRD > - bool "Spreadtrum SoC platform" > + tristate "Spreadtrum SoC platform" > help > Support for Spreadtrum ARM based SoCs Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH 1/2] arm64: change ARCH_SPRD Kconfig to tristate 2020-03-09 8:03 ` [PATCH 1/2] arm64: change ARCH_SPRD Kconfig to tristate Geert Uytterhoeven @ 2020-03-09 8:32 ` Chunyan Zhang 2020-03-09 10:32 ` Geert Uytterhoeven 0 siblings, 1 reply; 18+ messages in thread From: Chunyan Zhang @ 2020-03-09 8:32 UTC (permalink / raw) To: Geert Uytterhoeven Cc: kernel-team, Catalin Marinas, Greg Kroah-Hartman, Linux Kernel Mailing List, Chunyan Zhang, open list:SERIAL DRIVERS, Jiri Slaby, Baolin Wang, Orson Zhai, Will Deacon, Linux ARM Hi Geert, On Mon, 9 Mar 2020 at 16:03, Geert Uytterhoeven <geert@linux-m68k.org> wrote: > > Hi Chunyan. > > On Thu, Mar 5, 2020 at 11:33 AM Chunyan Zhang <zhang.lyra@gmail.com> wrote: > > From: Chunyan Zhang <chunyan.zhang@unisoc.com> > > > > The default value of Kconfig for almost all sprd drivers are the same with > > ARCH_SPRD, making these drivers built as modules as default would be easier > > if we can set ARCH_SPRD as 'm', so this patch change ARCH_SPRD to tristate. > > > > Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com> > > Can you actually boot a kernel on a Spreadtrum platform when all platform > and driver support is modular? Yes, even if all drivers are modular. But I hope serial can be builtin, then I can have a console to see kernel output before loading modules. Also, this's what Google GKI [1] asked :) Regards, Chunyan [1] https://arstechnica.com/gadgets/2019/11/google-outlines-plans-for-mainline-linux-kernel-support-in-android/ > > > +++ b/arch/arm64/Kconfig.platforms > > @@ -249,7 +249,7 @@ config ARCH_TEGRA > > This enables support for the NVIDIA Tegra SoC family. > > > > config ARCH_SPRD > > - bool "Spreadtrum SoC platform" > > + tristate "Spreadtrum SoC platform" > > help > > Support for Spreadtrum ARM based SoCs > > Gr{oetje,eeting}s, > > Geert > > -- > Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org > > In personal conversations with technical people, I call myself a hacker. But > when I'm talking to journalists I just say "programmer" or something like that. > -- Linus Torvalds _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH 1/2] arm64: change ARCH_SPRD Kconfig to tristate 2020-03-09 8:32 ` Chunyan Zhang @ 2020-03-09 10:32 ` Geert Uytterhoeven 2020-03-10 4:19 ` Sandeep Patil 2020-03-10 9:41 ` Orson Zhai 0 siblings, 2 replies; 18+ messages in thread From: Geert Uytterhoeven @ 2020-03-09 10:32 UTC (permalink / raw) To: Chunyan Zhang Cc: Android Kernel Team, Catalin Marinas, Greg Kroah-Hartman, Linux Kernel Mailing List, Chunyan Zhang, open list:SERIAL DRIVERS, Jiri Slaby, Baolin Wang, Orson Zhai, Will Deacon, Linux ARM Hi Chunyan, On Mon, Mar 9, 2020 at 9:32 AM Chunyan Zhang <zhang.lyra@gmail.com> wrote: > On Mon, 9 Mar 2020 at 16:03, Geert Uytterhoeven <geert@linux-m68k.org> wrote: > > On Thu, Mar 5, 2020 at 11:33 AM Chunyan Zhang <zhang.lyra@gmail.com> wrote: > > > From: Chunyan Zhang <chunyan.zhang@unisoc.com> > > > > > > The default value of Kconfig for almost all sprd drivers are the same with > > > ARCH_SPRD, making these drivers built as modules as default would be easier > > > if we can set ARCH_SPRD as 'm', so this patch change ARCH_SPRD to tristate. > > > > > > Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com> > > > > Can you actually boot a kernel on a Spreadtrum platform when all platform > > and driver support is modular? > > Yes, even if all drivers are modular. Cool. No hard dependencies on e.g. regulators that are turned off when unused? > But I hope serial can be builtin, then I can have a console to see > kernel output before loading modules. No dependency on the clock driver? Oh, I see you have a hack in the serial driver, to assume default values when the serial port's parent clock is not found. That may limit use of the other serial ports, depending on the actual serial hardware. And on Sharkl64, the serial port's clock is a fixed-clock anyway, so you don't even need the hack. But in general you cannot rely on that, especially if your SoC has clock and/or power domains. BTW, what about the watchdog driver? That one does need a clock, and loading it too late will reboot your system. > Also, this's what Google GKI [1] asked :) > > Regards, > Chunyan > > [1] https://arstechnica.com/gadgets/2019/11/google-outlines-plans-for-mainline-linux-kernel-support-in-android/ Let's see how having everything modular works out on an SoC where all hardware is part of a clock and power domain. Thanks! Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH 1/2] arm64: change ARCH_SPRD Kconfig to tristate 2020-03-09 10:32 ` Geert Uytterhoeven @ 2020-03-10 4:19 ` Sandeep Patil 2020-03-10 4:27 ` Sandeep Patil 2020-03-10 9:41 ` Orson Zhai 1 sibling, 1 reply; 18+ messages in thread From: Sandeep Patil @ 2020-03-10 4:19 UTC (permalink / raw) To: Geert Uytterhoeven Cc: Android Kernel Team, Catalin Marinas, saravanak, Greg Kroah-Hartman, Chunyan Zhang, Linux Kernel Mailing List, Chunyan Zhang, open list:SERIAL DRIVERS, Jiri Slaby, Baolin Wang, Orson Zhai, Will Deacon, Linux ARM Hi Geert, On Mon, Mar 09, 2020 at 11:32:06AM +0100, Geert Uytterhoeven wrote: > Hi Chunyan, > > On Mon, Mar 9, 2020 at 9:32 AM Chunyan Zhang <zhang.lyra@gmail.com> wrote: > > On Mon, 9 Mar 2020 at 16:03, Geert Uytterhoeven <geert@linux-m68k.org> wrote: > > > On Thu, Mar 5, 2020 at 11:33 AM Chunyan Zhang <zhang.lyra@gmail.com> wrote: > > > > From: Chunyan Zhang <chunyan.zhang@unisoc.com> > > > > > > > > The default value of Kconfig for almost all sprd drivers are the same with > > > > ARCH_SPRD, making these drivers built as modules as default would be easier > > > > if we can set ARCH_SPRD as 'm', so this patch change ARCH_SPRD to tristate. > > > > > > > > Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com> > > > > > > Can you actually boot a kernel on a Spreadtrum platform when all platform > > > and driver support is modular? > > > > Yes, even if all drivers are modular. > > Cool. No hard dependencies on e.g. regulators that are turned off when > unused? > > > But I hope serial can be builtin, then I can have a console to see > > kernel output before loading modules. > > No dependency on the clock driver? > Oh, I see you have a hack in the serial driver, to assume default > values when the serial port's parent clock is not found. That may > limit use of the other serial ports, depending on the actual serial > hardware. > And on Sharkl64, the serial port's clock is a fixed-clock anyway, so > you don't even need the hack. > > But in general you cannot rely on that, especially if your SoC has clock > and/or power domains. > > BTW, what about the watchdog driver? That one does need a clock, and > loading it too late will reboot your system. > > > Also, this's what Google GKI [1] asked :) > > > > Regards, > > Chunyan > > > > [1] https://arstechnica.com/gadgets/2019/11/google-outlines-plans-for-mainline-linux-kernel-support-in-android/ > > Let's see how having everything modular works out on an SoC where all > hardware is part of a clock and power domain. I'm curious, are there any problems that we should be aware of? We know about the regulator sync state and consumer-supplier dependencies. [1] (Adding Saravana inline) Thanks, - ssp _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH 1/2] arm64: change ARCH_SPRD Kconfig to tristate 2020-03-10 4:19 ` Sandeep Patil @ 2020-03-10 4:27 ` Sandeep Patil 2020-03-10 8:47 ` Geert Uytterhoeven 0 siblings, 1 reply; 18+ messages in thread From: Sandeep Patil @ 2020-03-10 4:27 UTC (permalink / raw) To: Geert Uytterhoeven Cc: Android Kernel Team, Catalin Marinas, saravanak, Greg Kroah-Hartman, Chunyan Zhang, Linux Kernel Mailing List, Chunyan Zhang, open list:SERIAL DRIVERS, Jiri Slaby, Baolin Wang, Orson Zhai, Will Deacon, Linux ARM On Mon, Mar 09, 2020 at 09:19:03PM -0700, Sandeep Patil wrote: > Hi Geert, > > On Mon, Mar 09, 2020 at 11:32:06AM +0100, Geert Uytterhoeven wrote: > > Hi Chunyan, > > > > On Mon, Mar 9, 2020 at 9:32 AM Chunyan Zhang <zhang.lyra@gmail.com> wrote: > > > On Mon, 9 Mar 2020 at 16:03, Geert Uytterhoeven <geert@linux-m68k.org> wrote: > > > > On Thu, Mar 5, 2020 at 11:33 AM Chunyan Zhang <zhang.lyra@gmail.com> wrote: > > > > > From: Chunyan Zhang <chunyan.zhang@unisoc.com> > > > > > > > > > > The default value of Kconfig for almost all sprd drivers are the same with > > > > > ARCH_SPRD, making these drivers built as modules as default would be easier > > > > > if we can set ARCH_SPRD as 'm', so this patch change ARCH_SPRD to tristate. > > > > > > > > > > Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com> > > > > > > > > Can you actually boot a kernel on a Spreadtrum platform when all platform > > > > and driver support is modular? > > > > > > Yes, even if all drivers are modular. > > > > Cool. No hard dependencies on e.g. regulators that are turned off when > > unused? > > > > > But I hope serial can be builtin, then I can have a console to see > > > kernel output before loading modules. > > > > No dependency on the clock driver? > > Oh, I see you have a hack in the serial driver, to assume default > > values when the serial port's parent clock is not found. That may > > limit use of the other serial ports, depending on the actual serial > > hardware. > > And on Sharkl64, the serial port's clock is a fixed-clock anyway, so > > you don't even need the hack. > > > > But in general you cannot rely on that, especially if your SoC has clock > > and/or power domains. > > > > BTW, what about the watchdog driver? That one does need a clock, and > > loading it too late will reboot your system. > > > > > Also, this's what Google GKI [1] asked :) > > > > > > Regards, > > > Chunyan > > > > > > [1] https://arstechnica.com/gadgets/2019/11/google-outlines-plans-for-mainline-linux-kernel-support-in-android/ > > > > Let's see how having everything modular works out on an SoC where all > > hardware is part of a clock and power domain. > > I'm curious, are there any problems that we should be aware of? We know about > the regulator sync state and consumer-supplier dependencies. [1] > > (Adding Saravana inline) > (oops, forgot to paste the link to presentation) 1. https://linuxplumbersconf.org/event/4/contributions/402/attachments/320/544/Solving_issues_associated_with_modules_and_supplier-consumer_dependencies.pdf _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH 1/2] arm64: change ARCH_SPRD Kconfig to tristate 2020-03-10 4:27 ` Sandeep Patil @ 2020-03-10 8:47 ` Geert Uytterhoeven 0 siblings, 0 replies; 18+ messages in thread From: Geert Uytterhoeven @ 2020-03-10 8:47 UTC (permalink / raw) To: Sandeep Patil Cc: Android Kernel Team, Catalin Marinas, saravanak, Greg Kroah-Hartman, Chunyan Zhang, Linux Kernel Mailing List, Chunyan Zhang, open list:SERIAL DRIVERS, Jiri Slaby, Baolin Wang, Orson Zhai, Will Deacon, Linux ARM Hi Sandeep, On Tue, Mar 10, 2020 at 5:27 AM Sandeep Patil <sspatil@android.com> wrote: > On Mon, Mar 09, 2020 at 09:19:03PM -0700, Sandeep Patil wrote: > > On Mon, Mar 09, 2020 at 11:32:06AM +0100, Geert Uytterhoeven wrote: > > > On Mon, Mar 9, 2020 at 9:32 AM Chunyan Zhang <zhang.lyra@gmail.com> wrote: > > > > On Mon, 9 Mar 2020 at 16:03, Geert Uytterhoeven <geert@linux-m68k.org> wrote: > > > > > On Thu, Mar 5, 2020 at 11:33 AM Chunyan Zhang <zhang.lyra@gmail.com> wrote: > > > > > > From: Chunyan Zhang <chunyan.zhang@unisoc.com> > > > > > > > > > > > > The default value of Kconfig for almost all sprd drivers are the same with > > > > > > ARCH_SPRD, making these drivers built as modules as default would be easier > > > > > > if we can set ARCH_SPRD as 'm', so this patch change ARCH_SPRD to tristate. > > > > > > > > > > > > Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com> > > > > > > > > > > Can you actually boot a kernel on a Spreadtrum platform when all platform > > > > > and driver support is modular? > > > > > > > > Yes, even if all drivers are modular. > > > > > > Cool. No hard dependencies on e.g. regulators that are turned off when > > > unused? > > > > > > > But I hope serial can be builtin, then I can have a console to see > > > > kernel output before loading modules. > > > > > > No dependency on the clock driver? > > > Oh, I see you have a hack in the serial driver, to assume default > > > values when the serial port's parent clock is not found. That may > > > limit use of the other serial ports, depending on the actual serial > > > hardware. > > > And on Sharkl64, the serial port's clock is a fixed-clock anyway, so > > > you don't even need the hack. > > > > > > But in general you cannot rely on that, especially if your SoC has clock > > > and/or power domains. So I gave it a try on my platform (R-Car), with just the serial driver builtin. I can see the kernel booting using earlycon. However, the serial driver is never probed, as the pin control driver is missing. And after that, it would need the clock domain (power domain and clock drivers), and more serial clock inputs (clock driver, again). Fortunately DMA is optional (dmac driver, and optional iommu driver). I guess core platform-specific drivers can be loaded from the initramfs, after which the serial driver would be probed, finally. If the initramfs includes a storage driver, anything else can be loaded from e.g. eMMC. > > > > Also, this's what Google GKI [1] asked :) > > > > [1] https://arstechnica.com/gadgets/2019/11/google-outlines-plans-for-mainline-linux-kernel-support-in-android/ > > > > > > Let's see how having everything modular works out on an SoC where all > > > hardware is part of a clock and power domain. > > > > I'm curious, are there any problems that we should be aware of? We know about > > the regulator sync state and consumer-supplier dependencies. [1] Care must be taken, as probe deferral behaves differently after late_initcall time (see driver_deferred_probe_check_state_continue), which may cause issues with "optional" components like DMA controllers and IOMMUs. Unused clocks and power domains are not turned off, unlike for the builtin case. On some SoCs, even the interrupt controller (GIC) may be part of a clock and/or power domain, while the GIC driver is not aware of that. For the clock, that is handled by CLK_IS_CRITICAL in the clock driver. For power domains, that is not handled explicitly on Renesas SoCs, as the GIC is always in the same power domain as other devices that are Runtime PM-aware. But if those devices would have modular drivers, that power domain could still be turned off. So on a modern ARM system, I assume a generic kernel with no vendor-specific drivers builtin can indeed work. On older systems, without an ARM architectured timer, you will need at least the platform-specific timer driver (and the clock driver) builtin. Assumed the timer's power domain has been powered up by the firmware. > (oops, forgot to paste the link to presentation) > 1. https://linuxplumbersconf.org/event/4/contributions/402/attachments/320/544/Solving_issues_associated_with_modules_and_supplier-consumer_dependencies.pdf Thanks, hadn't seen that presentation. It matches my understanding. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH 1/2] arm64: change ARCH_SPRD Kconfig to tristate 2020-03-09 10:32 ` Geert Uytterhoeven 2020-03-10 4:19 ` Sandeep Patil @ 2020-03-10 9:41 ` Orson Zhai 2020-03-10 9:52 ` Geert Uytterhoeven 1 sibling, 1 reply; 18+ messages in thread From: Orson Zhai @ 2020-03-10 9:41 UTC (permalink / raw) To: Geert Uytterhoeven Cc: Android Kernel Team, Catalin Marinas, Greg Kroah-Hartman, Chunyan Zhang, Linux Kernel Mailing List, Chunyan Zhang, open list:SERIAL DRIVERS, Jiri Slaby, Baolin Wang, Will Deacon, Linux ARM Hi Geert, On Mon, Mar 9, 2020 at 6:32 PM Geert Uytterhoeven <geert@linux-m68k.org> wrote: > > Hi Chunyan, > > On Mon, Mar 9, 2020 at 9:32 AM Chunyan Zhang <zhang.lyra@gmail.com> wrote: > > On Mon, 9 Mar 2020 at 16:03, Geert Uytterhoeven <geert@linux-m68k.org> wrote: > > > On Thu, Mar 5, 2020 at 11:33 AM Chunyan Zhang <zhang.lyra@gmail.com> wrote: > > > > From: Chunyan Zhang <chunyan.zhang@unisoc.com> > > > > > > > > The default value of Kconfig for almost all sprd drivers are the same with > > > > ARCH_SPRD, making these drivers built as modules as default would be easier > > > > if we can set ARCH_SPRD as 'm', so this patch change ARCH_SPRD to tristate. > > > > > > > > Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com> > > > > > > Can you actually boot a kernel on a Spreadtrum platform when all platform > > > and driver support is modular? > > > > Yes, even if all drivers are modular. > > Cool. No hard dependencies on e.g. regulators that are turned off when > unused? > > > But I hope serial can be builtin, then I can have a console to see > > kernel output before loading modules. > > No dependency on the clock driver? > Oh, I see you have a hack in the serial driver, to assume default > values when the serial port's parent clock is not found. That may > limit use of the other serial ports, depending on the actual serial > hardware. There is an function named "sprd_uart_is_console()" in the driver code. So the hack could be only applied when the port is identified as console. And other ports might return PROBE_DEFER until the clock is ready. Could it work out of the limitation? -Orson > And on Sharkl64, the serial port's clock is a fixed-clock anyway, so > you don't even need the hack. > > But in general you cannot rely on that, especially if your SoC has clock > and/or power domains. > > BTW, what about the watchdog driver? That one does need a clock, and > loading it too late will reboot your system. > > > Also, this's what Google GKI [1] asked :) > > > > Regards, > > Chunyan > > > > [1] https://arstechnica.com/gadgets/2019/11/google-outlines-plans-for-mainline-linux-kernel-support-in-android/ > > Let's see how having everything modular works out on an SoC where all > hardware is part of a clock and power domain. > > Thanks! > > Gr{oetje,eeting}s, > > Geert > > -- > Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org > > In personal conversations with technical people, I call myself a hacker. But > when I'm talking to journalists I just say "programmer" or something like that. > -- Linus Torvalds _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH 1/2] arm64: change ARCH_SPRD Kconfig to tristate 2020-03-10 9:41 ` Orson Zhai @ 2020-03-10 9:52 ` Geert Uytterhoeven 2020-03-10 10:13 ` Orson Zhai 0 siblings, 1 reply; 18+ messages in thread From: Geert Uytterhoeven @ 2020-03-10 9:52 UTC (permalink / raw) To: Orson Zhai Cc: Android Kernel Team, Catalin Marinas, Greg Kroah-Hartman, Chunyan Zhang, Linux Kernel Mailing List, Chunyan Zhang, open list:SERIAL DRIVERS, Jiri Slaby, Baolin Wang, Will Deacon, Linux ARM Hi Orson, On Tue, Mar 10, 2020 at 10:41 AM Orson Zhai <orsonzhai@gmail.com> wrote: > On Mon, Mar 9, 2020 at 6:32 PM Geert Uytterhoeven <geert@linux-m68k.org> wrote: > > On Mon, Mar 9, 2020 at 9:32 AM Chunyan Zhang <zhang.lyra@gmail.com> wrote: > > > On Mon, 9 Mar 2020 at 16:03, Geert Uytterhoeven <geert@linux-m68k.org> wrote: > > > > On Thu, Mar 5, 2020 at 11:33 AM Chunyan Zhang <zhang.lyra@gmail.com> wrote: > > > > > From: Chunyan Zhang <chunyan.zhang@unisoc.com> > > > > > > > > > > The default value of Kconfig for almost all sprd drivers are the same with > > > > > ARCH_SPRD, making these drivers built as modules as default would be easier > > > > > if we can set ARCH_SPRD as 'm', so this patch change ARCH_SPRD to tristate. > > > > > > > > > > Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com> > > > > > > > > Can you actually boot a kernel on a Spreadtrum platform when all platform > > > > and driver support is modular? > > > > > > Yes, even if all drivers are modular. > > > > Cool. No hard dependencies on e.g. regulators that are turned off when > > unused? > > > > > But I hope serial can be builtin, then I can have a console to see > > > kernel output before loading modules. > > > > No dependency on the clock driver? > > Oh, I see you have a hack in the serial driver, to assume default > > values when the serial port's parent clock is not found. That may > > limit use of the other serial ports, depending on the actual serial > > hardware. > > There is an function named "sprd_uart_is_console()" in the driver > code. So the hack could be only applied when the > port is identified as console. And other ports might return > PROBE_DEFER until the clock is ready. > > Could it work out of the limitation? Yes, that could work. You also have only a single SPRD_DEFAULT_SOURCE_CLK, which makes it simple to handle. For other SoCs, there may be a variation of possible values, depending on SoC and/or board. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH 1/2] arm64: change ARCH_SPRD Kconfig to tristate 2020-03-10 9:52 ` Geert Uytterhoeven @ 2020-03-10 10:13 ` Orson Zhai 0 siblings, 0 replies; 18+ messages in thread From: Orson Zhai @ 2020-03-10 10:13 UTC (permalink / raw) To: Geert Uytterhoeven Cc: Android Kernel Team, Catalin Marinas, Greg Kroah-Hartman, Chunyan Zhang, Linux Kernel Mailing List, Chunyan Zhang, open list:SERIAL DRIVERS, Jiri Slaby, Baolin Wang, Will Deacon, Linux ARM On Tue, Mar 10, 2020 at 5:52 PM Geert Uytterhoeven <geert@linux-m68k.org> wrote: > > Hi Orson, > > On Tue, Mar 10, 2020 at 10:41 AM Orson Zhai <orsonzhai@gmail.com> wrote: > > On Mon, Mar 9, 2020 at 6:32 PM Geert Uytterhoeven <geert@linux-m68k.org> wrote: > > > On Mon, Mar 9, 2020 at 9:32 AM Chunyan Zhang <zhang.lyra@gmail.com> wrote: > > > > On Mon, 9 Mar 2020 at 16:03, Geert Uytterhoeven <geert@linux-m68k.org> wrote: > > > > > On Thu, Mar 5, 2020 at 11:33 AM Chunyan Zhang <zhang.lyra@gmail.com> wrote: > > > > > > From: Chunyan Zhang <chunyan.zhang@unisoc.com> > > > > > > > > > > > > The default value of Kconfig for almost all sprd drivers are the same with > > > > > > ARCH_SPRD, making these drivers built as modules as default would be easier > > > > > > if we can set ARCH_SPRD as 'm', so this patch change ARCH_SPRD to tristate. > > > > > > > > > > > > Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com> > > > > > > > > > > Can you actually boot a kernel on a Spreadtrum platform when all platform > > > > > and driver support is modular? > > > > > > > > Yes, even if all drivers are modular. > > > > > > Cool. No hard dependencies on e.g. regulators that are turned off when > > > unused? > > > > > > > But I hope serial can be builtin, then I can have a console to see > > > > kernel output before loading modules. > > > > > > No dependency on the clock driver? > > > Oh, I see you have a hack in the serial driver, to assume default > > > values when the serial port's parent clock is not found. That may > > > limit use of the other serial ports, depending on the actual serial > > > hardware. > > > > There is an function named "sprd_uart_is_console()" in the driver > > code. So the hack could be only applied when the > > port is identified as console. And other ports might return > > PROBE_DEFER until the clock is ready. > > > > Could it work out of the limitation? > > Yes, that could work. You also have only a single SPRD_DEFAULT_SOURCE_CLK, > which makes it simple to handle. > For other SoCs, there may be a variation of possible values, depending on > SoC and/or board. Ok, thanks. -Orson > > Gr{oetje,eeting}s, > > Geert > > -- > Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org > > In personal conversations with technical people, I call myself a hacker. But > when I'm talking to journalists I just say "programmer" or something like that. > -- Linus Torvalds _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply [flat|nested] 18+ messages in thread
end of thread, other threads:[~2020-03-10 10:14 UTC | newest] Thread overview: 18+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2020-03-05 10:32 [PATCH 1/2] arm64: change ARCH_SPRD Kconfig to tristate Chunyan Zhang 2020-03-05 10:32 ` [PATCH 2/2] tty: serial: make SERIAL_SPRD not depend on ARCH_SPRD Chunyan Zhang 2020-03-06 12:41 ` Geert Uytterhoeven 2020-03-09 1:17 ` Chunyan Zhang 2020-03-09 8:01 ` Geert Uytterhoeven 2020-03-09 8:42 ` Chunyan Zhang 2020-03-09 10:32 ` Geert Uytterhoeven 2020-03-09 11:15 ` Chunyan Zhang 2020-03-09 14:10 ` Orson Zhai 2020-03-09 8:03 ` [PATCH 1/2] arm64: change ARCH_SPRD Kconfig to tristate Geert Uytterhoeven 2020-03-09 8:32 ` Chunyan Zhang 2020-03-09 10:32 ` Geert Uytterhoeven 2020-03-10 4:19 ` Sandeep Patil 2020-03-10 4:27 ` Sandeep Patil 2020-03-10 8:47 ` Geert Uytterhoeven 2020-03-10 9:41 ` Orson Zhai 2020-03-10 9:52 ` Geert Uytterhoeven 2020-03-10 10:13 ` Orson Zhai
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