| Message ID | 20200109100754.1007705-3-marex@denx.de |
|---|---|
| State | New |
| Headers | show |
| Series | [1/3] mtd: rawnand: denali-spl: Add missing hardware init | expand |
On Thu, Jan 9, 2020 at 7:08 PM Marek Vasut <marex at denx.de> wrote: > > Legacy kernel versions for SoCFPGA may not implement proper reset > handling. Apply the same approach as SoCFPGA reset driver, check > environment variable "socfpga_legacy_reset_compat", and if it is > set, do not reset the IP before booting Linux. This way, even the > older kernel versions can be booted by up to date U-Boot. > > Signed-off-by: Marek Vasut <marex at denx.de> > Cc: Masahiro Yamada <yamada.masahiro at socionext.com> > --- > drivers/mtd/nand/raw/denali_dt.c | 12 ++++++++++++ > 1 file changed, 12 insertions(+) > > diff --git a/drivers/mtd/nand/raw/denali_dt.c b/drivers/mtd/nand/raw/denali_dt.c > index 2c9e249ab6..d35f2a3543 100644 > --- a/drivers/mtd/nand/raw/denali_dt.c > +++ b/drivers/mtd/nand/raw/denali_dt.c > @@ -148,6 +148,18 @@ static int denali_dt_remove(struct udevice *dev) > { > struct denali_nand_info *denali = dev_get_priv(dev); > > +#if CONFIG_IS_ENABLED(ARCH_SOCFPGA) > + /* > + * Legacy kernel versions do not implement proper reset handling on > + * SoCFPGA. To let those older kernel versions work, reuse the same > + * approach as the SoCFPGA reset driver does -- check environment > + * variable socfpga_legacy_reset_compat and avoid resetting the IP > + * before booting the kernel if it is set to 1. > + */ > + if (env_get_ulong("socfpga_legacy_reset_compat", 10, 0)) > + return 0; > +#endif > + > return reset_release_bulk(&denali->resets); > } Why don't you simply remove reset_release_bulk() ? > > -- > 2.24.1 >
On 1/9/20 12:04 PM, Masahiro Yamada wrote: > On Thu, Jan 9, 2020 at 7:08 PM Marek Vasut <marex at denx.de> wrote: >> >> Legacy kernel versions for SoCFPGA may not implement proper reset >> handling. Apply the same approach as SoCFPGA reset driver, check >> environment variable "socfpga_legacy_reset_compat", and if it is >> set, do not reset the IP before booting Linux. This way, even the >> older kernel versions can be booted by up to date U-Boot. >> >> Signed-off-by: Marek Vasut <marex at denx.de> >> Cc: Masahiro Yamada <yamada.masahiro at socionext.com> >> --- >> drivers/mtd/nand/raw/denali_dt.c | 12 ++++++++++++ >> 1 file changed, 12 insertions(+) >> >> diff --git a/drivers/mtd/nand/raw/denali_dt.c b/drivers/mtd/nand/raw/denali_dt.c >> index 2c9e249ab6..d35f2a3543 100644 >> --- a/drivers/mtd/nand/raw/denali_dt.c >> +++ b/drivers/mtd/nand/raw/denali_dt.c >> @@ -148,6 +148,18 @@ static int denali_dt_remove(struct udevice *dev) >> { >> struct denali_nand_info *denali = dev_get_priv(dev); >> >> +#if CONFIG_IS_ENABLED(ARCH_SOCFPGA) >> + /* >> + * Legacy kernel versions do not implement proper reset handling on >> + * SoCFPGA. To let those older kernel versions work, reuse the same >> + * approach as the SoCFPGA reset driver does -- check environment >> + * variable socfpga_legacy_reset_compat and avoid resetting the IP >> + * before booting the kernel if it is set to 1. >> + */ >> + if (env_get_ulong("socfpga_legacy_reset_compat", 10, 0)) >> + return 0; >> +#endif >> + >> return reset_release_bulk(&denali->resets); >> } > > > Why don't you simply remove reset_release_bulk() ? Because once mainline has proper reset handling, this can be used only for legacy kernel versions.
On Thu, Jan 9, 2020 at 8:16 PM Marek Vasut <marex at denx.de> wrote: > > On 1/9/20 12:04 PM, Masahiro Yamada wrote: > > On Thu, Jan 9, 2020 at 7:08 PM Marek Vasut <marex at denx.de> wrote: > >> > >> Legacy kernel versions for SoCFPGA may not implement proper reset > >> handling. Apply the same approach as SoCFPGA reset driver, check > >> environment variable "socfpga_legacy_reset_compat", and if it is > >> set, do not reset the IP before booting Linux. This way, even the > >> older kernel versions can be booted by up to date U-Boot. > >> > >> Signed-off-by: Marek Vasut <marex at denx.de> > >> Cc: Masahiro Yamada <yamada.masahiro at socionext.com> > >> --- > >> drivers/mtd/nand/raw/denali_dt.c | 12 ++++++++++++ > >> 1 file changed, 12 insertions(+) > >> > >> diff --git a/drivers/mtd/nand/raw/denali_dt.c b/drivers/mtd/nand/raw/denali_dt.c > >> index 2c9e249ab6..d35f2a3543 100644 > >> --- a/drivers/mtd/nand/raw/denali_dt.c > >> +++ b/drivers/mtd/nand/raw/denali_dt.c > >> @@ -148,6 +148,18 @@ static int denali_dt_remove(struct udevice *dev) > >> { > >> struct denali_nand_info *denali = dev_get_priv(dev); > >> > >> +#if CONFIG_IS_ENABLED(ARCH_SOCFPGA) > >> + /* > >> + * Legacy kernel versions do not implement proper reset handling on > >> + * SoCFPGA. To let those older kernel versions work, reuse the same > >> + * approach as the SoCFPGA reset driver does -- check environment > >> + * variable socfpga_legacy_reset_compat and avoid resetting the IP > >> + * before booting the kernel if it is set to 1. > >> + */ > >> + if (env_get_ulong("socfpga_legacy_reset_compat", 10, 0)) > >> + return 0; > >> +#endif > >> + > >> return reset_release_bulk(&denali->resets); > >> } > > > > > > Why don't you simply remove reset_release_bulk() ? > > Because once mainline has proper reset handling, this can be used only > for legacy kernel versions. I am suffering for the same problem for the uniphier platform. The reset driver support for Linux will never be back-ported. So, it will continue to be a problem for Linux v4.19, v5.4, etc. reset_release_bulk() should go away.
On 1/9/20 1:11 PM, Masahiro Yamada wrote: > On Thu, Jan 9, 2020 at 8:16 PM Marek Vasut <marex at denx.de> wrote: >> >> On 1/9/20 12:04 PM, Masahiro Yamada wrote: >>> On Thu, Jan 9, 2020 at 7:08 PM Marek Vasut <marex at denx.de> wrote: >>>> >>>> Legacy kernel versions for SoCFPGA may not implement proper reset >>>> handling. Apply the same approach as SoCFPGA reset driver, check >>>> environment variable "socfpga_legacy_reset_compat", and if it is >>>> set, do not reset the IP before booting Linux. This way, even the >>>> older kernel versions can be booted by up to date U-Boot. >>>> >>>> Signed-off-by: Marek Vasut <marex at denx.de> >>>> Cc: Masahiro Yamada <yamada.masahiro at socionext.com> >>>> --- >>>> drivers/mtd/nand/raw/denali_dt.c | 12 ++++++++++++ >>>> 1 file changed, 12 insertions(+) >>>> >>>> diff --git a/drivers/mtd/nand/raw/denali_dt.c b/drivers/mtd/nand/raw/denali_dt.c >>>> index 2c9e249ab6..d35f2a3543 100644 >>>> --- a/drivers/mtd/nand/raw/denali_dt.c >>>> +++ b/drivers/mtd/nand/raw/denali_dt.c >>>> @@ -148,6 +148,18 @@ static int denali_dt_remove(struct udevice *dev) >>>> { >>>> struct denali_nand_info *denali = dev_get_priv(dev); >>>> >>>> +#if CONFIG_IS_ENABLED(ARCH_SOCFPGA) >>>> + /* >>>> + * Legacy kernel versions do not implement proper reset handling on >>>> + * SoCFPGA. To let those older kernel versions work, reuse the same >>>> + * approach as the SoCFPGA reset driver does -- check environment >>>> + * variable socfpga_legacy_reset_compat and avoid resetting the IP >>>> + * before booting the kernel if it is set to 1. >>>> + */ >>>> + if (env_get_ulong("socfpga_legacy_reset_compat", 10, 0)) >>>> + return 0; >>>> +#endif >>>> + >>>> return reset_release_bulk(&denali->resets); >>>> } >>> >>> >>> Why don't you simply remove reset_release_bulk() ? >> >> Because once mainline has proper reset handling, this can be used only >> for legacy kernel versions. > > > I am suffering for the same problem for the uniphier platform. The Denali NAND patches for Linux are currently stuck on your review too. > The reset driver support for Linux will never be back-ported. > So, it will continue to be a problem for Linux v4.19, v5.4, etc. > > reset_release_bulk() should go away. Once the Linux patches are upstream, we can just reset the NAND controller without problems. And that's the right thing to do, sometimes you don't want NAND to be available in Linux, and then it should be kept in reset.
On Thu, Jan 9, 2020 at 11:48 PM Marek Vasut <marex at denx.de> wrote: > > On 1/9/20 1:11 PM, Masahiro Yamada wrote: > > On Thu, Jan 9, 2020 at 8:16 PM Marek Vasut <marex at denx.de> wrote: > >> > >> On 1/9/20 12:04 PM, Masahiro Yamada wrote: > >>> On Thu, Jan 9, 2020 at 7:08 PM Marek Vasut <marex at denx.de> wrote: > >>>> > >>>> Legacy kernel versions for SoCFPGA may not implement proper reset > >>>> handling. Apply the same approach as SoCFPGA reset driver, check > >>>> environment variable "socfpga_legacy_reset_compat", and if it is > >>>> set, do not reset the IP before booting Linux. This way, even the > >>>> older kernel versions can be booted by up to date U-Boot. > >>>> > >>>> Signed-off-by: Marek Vasut <marex at denx.de> > >>>> Cc: Masahiro Yamada <yamada.masahiro at socionext.com> > >>>> --- > >>>> drivers/mtd/nand/raw/denali_dt.c | 12 ++++++++++++ > >>>> 1 file changed, 12 insertions(+) > >>>> > >>>> diff --git a/drivers/mtd/nand/raw/denali_dt.c b/drivers/mtd/nand/raw/denali_dt.c > >>>> index 2c9e249ab6..d35f2a3543 100644 > >>>> --- a/drivers/mtd/nand/raw/denali_dt.c > >>>> +++ b/drivers/mtd/nand/raw/denali_dt.c > >>>> @@ -148,6 +148,18 @@ static int denali_dt_remove(struct udevice *dev) > >>>> { > >>>> struct denali_nand_info *denali = dev_get_priv(dev); > >>>> > >>>> +#if CONFIG_IS_ENABLED(ARCH_SOCFPGA) > >>>> + /* > >>>> + * Legacy kernel versions do not implement proper reset handling on > >>>> + * SoCFPGA. To let those older kernel versions work, reuse the same > >>>> + * approach as the SoCFPGA reset driver does -- check environment > >>>> + * variable socfpga_legacy_reset_compat and avoid resetting the IP > >>>> + * before booting the kernel if it is set to 1. > >>>> + */ > >>>> + if (env_get_ulong("socfpga_legacy_reset_compat", 10, 0)) > >>>> + return 0; > >>>> +#endif > >>>> + > >>>> return reset_release_bulk(&denali->resets); > >>>> } > >>> > >>> > >>> Why don't you simply remove reset_release_bulk() ? > >> > >> Because once mainline has proper reset handling, this can be used only > >> for legacy kernel versions. > > > > > > I am suffering for the same problem for the uniphier platform. > > The Denali NAND patches for Linux are currently stuck on your review too. Huh? Which patch in Linux is stuck on my review? > > The reset driver support for Linux will never be back-ported. > > So, it will continue to be a problem for Linux v4.19, v5.4, etc. > > > > reset_release_bulk() should go away. > > Once the Linux patches are upstream, we can just reset the NAND > controller without problems. And that's the right thing to do, sometimes > you don't want NAND to be available in Linux, and then it should be kept > in reset. The NAND reset in Linux will be available in the future version (if my patch is applied). The stable kernels are maintained in 6 years. https://www.kernel.org/category/releases.html The EOF of Linux 5.4 is set at 2021.12, but following the recent rules, it will be extended to 2026 or so.
On 1/9/20 4:01 PM, Masahiro Yamada wrote: > On Thu, Jan 9, 2020 at 11:48 PM Marek Vasut <marex at denx.de> wrote: >> >> On 1/9/20 1:11 PM, Masahiro Yamada wrote: >>> On Thu, Jan 9, 2020 at 8:16 PM Marek Vasut <marex at denx.de> wrote: >>>> >>>> On 1/9/20 12:04 PM, Masahiro Yamada wrote: >>>>> On Thu, Jan 9, 2020 at 7:08 PM Marek Vasut <marex at denx.de> wrote: >>>>>> >>>>>> Legacy kernel versions for SoCFPGA may not implement proper reset >>>>>> handling. Apply the same approach as SoCFPGA reset driver, check >>>>>> environment variable "socfpga_legacy_reset_compat", and if it is >>>>>> set, do not reset the IP before booting Linux. This way, even the >>>>>> older kernel versions can be booted by up to date U-Boot. >>>>>> >>>>>> Signed-off-by: Marek Vasut <marex at denx.de> >>>>>> Cc: Masahiro Yamada <yamada.masahiro at socionext.com> >>>>>> --- >>>>>> drivers/mtd/nand/raw/denali_dt.c | 12 ++++++++++++ >>>>>> 1 file changed, 12 insertions(+) >>>>>> >>>>>> diff --git a/drivers/mtd/nand/raw/denali_dt.c b/drivers/mtd/nand/raw/denali_dt.c >>>>>> index 2c9e249ab6..d35f2a3543 100644 >>>>>> --- a/drivers/mtd/nand/raw/denali_dt.c >>>>>> +++ b/drivers/mtd/nand/raw/denali_dt.c >>>>>> @@ -148,6 +148,18 @@ static int denali_dt_remove(struct udevice *dev) >>>>>> { >>>>>> struct denali_nand_info *denali = dev_get_priv(dev); >>>>>> >>>>>> +#if CONFIG_IS_ENABLED(ARCH_SOCFPGA) >>>>>> + /* >>>>>> + * Legacy kernel versions do not implement proper reset handling on >>>>>> + * SoCFPGA. To let those older kernel versions work, reuse the same >>>>>> + * approach as the SoCFPGA reset driver does -- check environment >>>>>> + * variable socfpga_legacy_reset_compat and avoid resetting the IP >>>>>> + * before booting the kernel if it is set to 1. >>>>>> + */ >>>>>> + if (env_get_ulong("socfpga_legacy_reset_compat", 10, 0)) >>>>>> + return 0; >>>>>> +#endif >>>>>> + >>>>>> return reset_release_bulk(&denali->resets); >>>>>> } >>>>> >>>>> >>>>> Why don't you simply remove reset_release_bulk() ? >>>> >>>> Because once mainline has proper reset handling, this can be used only >>>> for legacy kernel versions. >>> >>> >>> I am suffering for the same problem for the uniphier platform. >> >> The Denali NAND patches for Linux are currently stuck on your review too. > > Huh? > > Which patch in Linux is stuck on my review? [PATCH V2] mtd: rawnand: denali_dt: Add support for configuring SPARE_AREA_SKIP_BYTES >>> The reset driver support for Linux will never be back-ported. >>> So, it will continue to be a problem for Linux v4.19, v5.4, etc. >>> >>> reset_release_bulk() should go away. >> >> Once the Linux patches are upstream, we can just reset the NAND >> controller without problems. And that's the right thing to do, sometimes >> you don't want NAND to be available in Linux, and then it should be kept >> in reset. > > > The NAND reset in Linux will be available in the future version > (if my patch is applied). Which patch ? > The stable kernels are maintained in 6 years. > > https://www.kernel.org/category/releases.html How is this relevant ? > The EOF of Linux 5.4 is set at 2021.12, but > following the recent rules, it will be extended > to 2026 or so. So, for all legacy kernel versions, enable this backward compatibility thingie.
diff --git a/drivers/mtd/nand/raw/denali_dt.c b/drivers/mtd/nand/raw/denali_dt.c index 2c9e249ab6..d35f2a3543 100644 --- a/drivers/mtd/nand/raw/denali_dt.c +++ b/drivers/mtd/nand/raw/denali_dt.c @@ -148,6 +148,18 @@ static int denali_dt_remove(struct udevice *dev) { struct denali_nand_info *denali = dev_get_priv(dev); +#if CONFIG_IS_ENABLED(ARCH_SOCFPGA) + /* + * Legacy kernel versions do not implement proper reset handling on + * SoCFPGA. To let those older kernel versions work, reuse the same + * approach as the SoCFPGA reset driver does -- check environment + * variable socfpga_legacy_reset_compat and avoid resetting the IP + * before booting the kernel if it is set to 1. + */ + if (env_get_ulong("socfpga_legacy_reset_compat", 10, 0)) + return 0; +#endif + return reset_release_bulk(&denali->resets); }
Legacy kernel versions for SoCFPGA may not implement proper reset handling. Apply the same approach as SoCFPGA reset driver, check environment variable "socfpga_legacy_reset_compat", and if it is set, do not reset the IP before booting Linux. This way, even the older kernel versions can be booted by up to date U-Boot. Signed-off-by: Marek Vasut <marex at denx.de> Cc: Masahiro Yamada <yamada.masahiro at socionext.com> --- drivers/mtd/nand/raw/denali_dt.c | 12 ++++++++++++ 1 file changed, 12 insertions(+)