linux.git/arch/csky/include, branch v5.12.5

csky: change a Kconfig symbol name to fix e1000 build error

2021-04-16T23:10:36+00:00

e1000's #define of CONFIG_RAM_BASE conflicts with a Kconfig symbol in
arch/csky/Kconfig.

The symbol in e1000 has been around longer, so change arch/csky/ to use
DRAM_BASE instead of RAM_BASE to remove the conflict.  (although e1000
is also a 2-line change)

Link: https://lkml.kernel.org/r/20210411055335.7111-1-rdunlap@infradead.org
Signed-off-by: Randy Dunlap 
Reported-by: kernel test robot 
Acked-by: Guo Ren 
Cc: Jesse Brandeburg 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

csky: Fixup compile error

2021-02-27T14:04:14+00:00

: error: C++ style comments are not allowed in ISO C90
 // Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
 ^
error: (this will be reported only once per input file)

Signed-off-by: Guo Ren

csky: Add VDSO with GENERIC_GETTIMEOFDAY, GENERIC_TIME_VSYSCALL, HAVE_GENERIC_VDSO

2021-02-27T08:35:09+00:00

It could help to reduce the latency of the time-related functions
in user space.

We have referenced arm's and riscv's implementation for the patch.

Signed-off-by: Guo Ren 
Cc: Vincent Chen 
Cc: Arnd Bergmann

csky: Fixup swapon

2021-02-27T08:32:54+00:00

Current csky's swappon is broken by wrong swap PTE entry format.
Now redesign the new format for abiv1 & abiv2 and make swappon +
zram work properly on csky machines.

C-SKY PTE has VALID, DIRTY to emulate PRESENT, READ, WRITE, EXEC
attributes. GLOBAL bit is shared by two pages in the same tlb
entry. So we need to keep GLOBAL, VALID, PRESENT zero in swp_pte.

To distinguish PAGE_NONE and swp_pte, we need to use an additional
bit (abiv1 is _PAGE_READ, abiv2 is _PAGE_WRITE).

Signed-off-by: Guo Ren 
Cc: Arnd Bergmann

csky: pgtable.h: Coding convention

2021-02-27T08:22:42+00:00

C-SKY page table attributes only have 'Dirty' and 'Valid' to
emulate 'PRESENT, READ, WRITE, EXEC, DIRTY, ACCESSED'.

This patch cleanup unnecessary definition.

Signed-off-by: Guo Ren 
Cc: Arnd Bergmann

csky: Fixup _PAGE_ACCESSED for default pgprot

2021-01-12T03:08:25+00:00

When the system memory is exhausted, linux will trigger kswapd to
shrink memory page cache. We found the csky's .text file mapping
pages would be reclaimed earlier than arm's elf. Because csky
doesn't give _PAGE_ACCESSED for default pgprot and in zap_pte_range

if (pte_young(ptent) &&
    likely(!(vma->vm_flags & VM_SEQ_READ)))
        mark_page_accessed(page);

mark_page_accessed will put the pages into active lru list.

[    3.652722] delete busybox page from inactive file list
Call Trace:
[<9012a376>] dump_stack+0xe/0x24
[<9012a370>] dump_stack+0x8/0x24
[<9005b780>] activate_page+0x2b4/0x2d4
[<90132502>] vsnprintf+0x2c6/0x374
[<9005b880>] mark_page_accessed+0xe0/0x150
[<9006903e>] unmap_page_range+0x166/0x33c
[<90021844>] get_signal+0x98/0x3b4
[<90069232>] unmap_single_vma+0x1e/0x24
[<90069462>] unmap_vmas+0x26/0x40
[<9006d3d8>] exit_mmap+0x60/0xbc
[<9006a140>] handle_mm_fault+0x700/0xcec
[<900426b2>] ktime_get_with_offset+0x86/0x130
[<90017566>] mmput+0x2e/0x90
[<9001a30a>] do_exit+0x13e/0x6f0
[<90015448>] page_fault_end+0x14/0x74
[<9001b4bc>] SyS_exit_group+0x0/0xc
[<9001b47c>] do_group_exit+0x2c/0x6c
[<9001b4c8>] __wake_up_parent+0x0/0x20
[<9001399e>] csky_systemcall+0x6e/0x72

csky will throw the pages at first and keep them in active lru
list later after real accessed, but arm would keep them in active
lru list at the beginning.

The following are statistics of different architecture styles:

Default _PAGE_ACCESSED: alpha, arm, arm64, ia64, m68k, microblaze,
			openrisc, powerpc, riscv, sh, um, x86,
			xtensa
Not def _PAGE_ACCESSED: arc, c6x, h8300, hexgon, mips, s390, nds32,
			nios2, parisc, sparc

Signed-off-by: Guo Ren 
Co-developed-by: Xu Kai 
Signed-off-by: Xu Kai

csky: remove unused including

2021-01-12T01:52:41+00:00

Remove including  that don't need it.

Signed-off-by: Tian Tao 
Signed-off-by: Guo Ren

csky: Reconstruct VDSO framework

2021-01-12T01:52:41+00:00

Reconstruct vdso framework to support future vsyscall,
vgettimeofday features. These are very important features to reduce
system calls into the kernel for performance improvement.

The patch is reference RISC-V's

Signed-off-by: Guo Ren 
Cc: Palmer Dabbelt

csky: Sync riscv mm/fault.c for easy maintenance

2021-01-12T01:52:41+00:00

Sync arch/riscv/mm/fault.c into arch/csky for easy maintenance.
Here are the patches related to the modification:

cac4d1d "riscv/mm/fault: Move no context handling to no_context()"
ac416a7 "riscv/mm/fault: Move vmalloc fault handling to vmalloc_fault()"
6c11ffb "riscv/mm/fault: Move fault error handling to mm_fault_error()"
afb8c6f "riscv/mm/fault: Move access error check to function"
bda281d "riscv/mm/fault: Simplify fault error handling"
a51271d "riscv/mm/fault: Move bad area handling to bad_area()"

Signed-off-by: Guo Ren 
Cc: Pekka Enberg 
Cc: Palmer Dabbelt 
Cc: Arnd Bergmann

csky: Fix TLB maintenance synchronization problem

2021-01-12T01:52:41+00:00

TLB invalidate didn't contain a barrier operation in csky cpu and
we need to prevent previous PTW response after TLB invalidation
instruction. Of cause, the ASID changing also needs to take care
of the issue.

CPU0                    CPU1
===============         ===============
set_pte
sync_is()        ->     See the previous set_pte for all harts
tlbi.vas         ->     Invalidate all harts TLB entry & flush pipeline

Signed-off-by: Guo Ren