Re: [PATCH v3 0/3] Add RISC-V 32 NOMMU support

[Jesse Taube]

On 3/7/23 21:51, Randy Dunlap wrote:
> On 3/7/23 18:33, Randy Dunlap wrote:
> > On 3/7/23 18:30, Jesse Taube wrote:
> > > On 3/7/23 21:16, Randy Dunlap wrote:
> > > > Hi--
> > > >
> > > > On 3/7/23 17:26, Jesse Taube wrote:
> > > > > On 2/28/23 23:42, Damien Le Moal wrote:
> > > > > > On 3/1/23 13:07, Randy Dunlap wrote:
> > > > > > > Hi--
> > > > > > >
> > > > > > > On 2/28/23 16:26, Jesse Taube wrote:
> > > > > > > > This patch-set aims to add NOMMU support to RV32.
> > > > > > > > Many people want to build simple emulators or HDL
> > > > > > > > models of RISC-V this patch makes it possible to
> > > > > > > > run linux on them.
> > > > > > > >
> > > > > > > > Yimin Gu is the original author of this set.
> > > > > > > > Submitted here:
> > > > > > > > https://lists.buildroot.org/pipermail/buildroot/2022-November/656134.html
> > > > > > > >
> > > > > > > > Though Jesse T rewrote the Dconf.
> > > > > > >
> > > > > > > Dconf?
> > > > > > >
> > > > > > > > The new set:
> > > > > > > > https://lists.buildroot.org/pipermail/buildroot/2022-December/658258.html
> > > > > > > > ---
> > > > > > > > V1->V2:
> > > > > > > >     - Add Conor's clock patch for implicit div64
> > > > > > > >     - Fix typo in commit title 3/3
> > > > > > > >     - Fix typo in commit description 2/3
> > > > > > > > V2->V3
> > > > > > > >     - Change from defconfig file to a PHONY config
> > > > > > > > ---
> > > > > > >
> > > > > > > Is this 'rv32_nommu_virt_defconfig' target the only build target
> > > > > > > that is supported?
> > > > > > >
> > > > > > > I ask because I applied the 3 patches and did 25 randconfig builds.
> > > > > > > 5 of them failed the same way:
> > > > > > >
> > > > > > > riscv32-linux-ld: drivers/soc/canaan/k210-sysctl.o: in function `k210_soc_early_init':
> > > > > > > k210-sysctl.c:(.init.text+0x78): undefined reference to `k210_clk_early_init'
> > > > > I can not recreate this error.
> > > > > can you send me the .config you used.
> > > > >
> > > > > Thanks,
> > > > > Jesse Taube
> > > >
> > > > Sure, it's attached.
> > >
> > > Hmmm, it links fine for me.
> > >
> > > objdump -x vmlinux | grep k210_clk_early_init
> > > 81e40124 g     F .init.text     00000088 k210_clk_early_init
> > >
> > > gcc version 11.3.0 (Buildroot 2022.11-361-g1be0d438f7)
> > > GNU assembler version 2.38 (riscv32-buildroot-linux-uclibc)
> > > GNU ld (GNU Binutils) 2.38
> > >
> > > what gcc version are you using?
> >
> >
> > gcc (SUSE Linux) 12.2.1 20230124 [revision 193f7e62815b4089dfaed4c2bd34fd4f10209e27]
> > from opensuse Tumbleweed.
> >
> > I'll try it on a current tree...
>
> OK, I don't know how it happened. I cannot reproduce it now.
> The failing .config files has CONFIG_MMU is not set (for RV32I), which
> appears to be impossible.
These patches add `CONFIG_MMU is not set` (for RV32I).
But no worries it seems to be a non issue  now.

Your thoughts Damien?

Thanks,
Jesse Taube
> Sorry to bother you.
>
> Thanks.
>
> > > > > > Arg. Forgot about that. k210 is rv64 only and while the clk driver could still
> > > > > > compile test with rv32 (or any arch), that driver provides the
> > > > > > k210_clk_early_init() function which is called very early in the boot process
> > > > > > from k210_soc_early_init(), which is an SOC_EARLY_INIT_DECLARE() call. The
> > > > > > problem may be there. Probably should be disabled for rv32 if no SoC need that
> > > > > > sort of early init call.
> > > > > >
> > > > > > > because
> > > > > > > # CONFIG_COMMON_CLK_K210 is not set
> > > > > > >
> > > > > > >
> > > > > > > Maybe SOC_CANAAN needs some more selects for required code?
> > > > > > >
> > > > > > > > Conor Dooley (1):
> > > > > > > >      clk: k210: remove an implicit 64-bit division
> > > > > > > >
> > > > > > > > Jesse Taube (1):
> > > > > > > >      riscv: configs: Add nommu PHONY defconfig for RV32
> > > > > > > >
> > > > > > > > Yimin Gu (1):
> > > > > > > >      riscv: Kconfig: Allow RV32 to build with no MMU
> > > > > > > >
> > > > > > > >     arch/riscv/Kconfig     | 5 ++---
> > > > > > > >     arch/riscv/Makefile    | 4 ++++
> > > > > > > >     drivers/clk/clk-k210.c | 2 +-
> > > > > > > >     3 files changed, 7 insertions(+), 4 deletions(-)