Commit Graph

1233516 Commits

Author SHA1 Message Date
Palmer Dabbelt
cb51bfee7f Merge patch series "riscv: hwprobe: add Zicond, Zacas and Ztso support"
Clément Léger <cleger@rivosinc.com> says:

This series add support for a few more extensions that are present in
the RVA22U64/RVA23U64 (either mandatory or optional) and that are useful
for userspace:
- Zicond
- Zacas
- Ztso

Series currently based on riscv/for-next.

* b4-shazam-lts:
  riscv: hwprobe: export Zicond extension
  riscv: hwprobe: export Zacas ISA extension
  riscv: add ISA extension parsing for Zacas
  dt-bindings: riscv: add Zacas ISA extension description
  riscv: hwprobe: export Ztso ISA extension
  riscv: add ISA extension parsing for Ztso

Link: https://lore.kernel.org/r/20231220155723.684081-1-cleger@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-09 20:14:51 -08:00
Clément Léger
3359866b40 riscv: hwprobe: export Zicond extension
Export the zicond extension to userspace using hwprobe.

Signed-off-by: Clément Léger <cleger@rivosinc.com>
Link: https://lore.kernel.org/r/20231220155723.684081-7-cleger@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-09 20:12:30 -08:00
Clément Léger
154a370612 riscv: hwprobe: export Zacas ISA extension
Export Zacas ISA extension through hwprobe.

Signed-off-by: Clément Léger <cleger@rivosinc.com>
Link: https://lore.kernel.org/r/20231220155723.684081-6-cleger@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-09 20:12:29 -08:00
Clément Léger
188a2122c8 riscv: add ISA extension parsing for Zacas
Add parsing for Zacas ISA extension which was ratified recently in the
riscv-zacas manual.

Signed-off-by: Clément Léger <cleger@rivosinc.com>
Link: https://lore.kernel.org/r/20231220155723.684081-5-cleger@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-09 20:12:28 -08:00
Clément Léger
cd7be4d02f dt-bindings: riscv: add Zacas ISA extension description
Add description for the Zacas ISA extension which was ratified recently.

Signed-off-by: Clément Léger <cleger@rivosinc.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20231220155723.684081-4-cleger@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-09 20:12:27 -08:00
Clément Léger
5b4d64a819 riscv: hwprobe: export Ztso ISA extension
Export the Ztso extension to userspace.

Signed-off-by: Clément Léger <cleger@rivosinc.com>
Link: https://lore.kernel.org/r/20231220155723.684081-3-cleger@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-09 20:12:26 -08:00
Clément Léger
1ec9f381e8 riscv: add ISA extension parsing for Ztso
Add support to parse the Ztso string in the riscv,isa string. The
bindings already supports it but not the ISA parsing code.

Signed-off-by: Clément Léger <cleger@rivosinc.com>
Link: https://lore.kernel.org/r/20231220155723.684081-2-cleger@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-09 20:12:25 -08:00
Al Viro
62694797f5 use linux/export.h rather than asm-generic/export.h
asm-generic/export.h is a wrapper for linux/export.h, with explicit request
to use linux/export.h directly.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Link: https://lore.kernel.org/r/20231214191922.GQ1674809@ZenIV
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-09 20:10:40 -08:00
Palmer Dabbelt
2bf8acbf54 Merge patch series "Fix XIP boot and make XIP testable in QEMU"
Frederik Haxel <haxel@fzi.de> says:

XIP boot seems to be broken for some time now. A likely reason why no one
seems to have noticed this is that XIP is more difficult to test, as it is
currently not easily testable with QEMU.

These patches fix the XIP boot and allow an XIP build without BUILTIN_DTB,
which in turn makes it easier to test an image with the QEMU virt machine.

* b4-shazam-merge:
  riscv: Allow disabling of BUILTIN_DTB for XIP
  riscv: Fixed wrong register in XIP_FIXUP_FLASH_OFFSET macro
  riscv: Make XIP bootable again

Link: https://lore.kernel.org/r/20231212130116.848530-1-haxel@fzi.de
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-09 20:10:39 -08:00
Song Shuai
a7565f4d06 riscv: Remove SHADOW_OVERFLOW_STACK_SIZE macro
The commit be97d0db5f ("riscv: VMAP_STACK overflow
detection thread-safe") got rid of `shadow_stack`,
so SHADOW_OVERFLOW_STACK_SIZE should be removed too.

Fixes: be97d0db5f ("riscv: VMAP_STACK overflow detection thread-safe")
Signed-off-by: Song Shuai <songshuaishuai@tinylab.org>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Link: https://lore.kernel.org/r/20231211110331.359534-1-songshuaishuai@tinylab.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-09 20:10:38 -08:00
Palmer Dabbelt
5c89186a32 Merge remote-tracking branch 'palmer/fixes' into for-next
I don't usually merge these in, but I missed sending a PR due to the
holidays.

* palmer/fixes:
  riscv: Fix set_direct_map_default_noflush() to reset _PAGE_EXEC
  riscv: Fix module_alloc() that did not reset the linear mapping permissions
  riscv: Fix wrong usage of lm_alias() when splitting a huge linear mapping
  riscv: Check if the code to patch lies in the exit section
  riscv: errata: andes: Probe for IOCP only once in boot stage
  riscv: Fix SMP when shadow call stacks are enabled
  dt-bindings: perf: riscv,pmu: drop unneeded quotes
  riscv: fix misaligned access handling of C.SWSP and C.SDSP
  RISC-V: hwprobe: Always use u64 for extension bits
  Support rv32 ULEB128 test
  riscv: Correct type casting in module loading
  riscv: Safely remove entries from relocation list

Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-09 20:10:32 -08:00
Ben Dooks
869436dae7 riscv; fix __user annotation in save_v_state()
The save_v_state() is technically sending a __user pointer through
__put_user() and thus is generating a sparse warning so force the
value to be "void *" to fix:

arch/riscv/kernel/signal.c:94:16: warning: incorrect type in initializer (different address spaces)
arch/riscv/kernel/signal.c:94:16: expected void *__val
arch/riscv/kernel/signal.c:94:16: got void [noderef] __user *[assigned] datap

Fixes: 8ee0b41898 ("riscv: signal: Add sigcontext save/restore for vector")
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Link: https://lore.kernel.org/r/20231123142708.261733-1-ben.dooks@codethink.co.uk
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-09 20:10:18 -08:00
Ben Dooks
ca0e433b41 riscv: fix __user annotation in traps_misaligned.c
The instruction reading code can read from either user or kernel addresses
and thus the use of __user on pointers to instructions depends on which
context. Fix a few sparse warnings by using __user for user-accesses and
remove it when not.

Fixes:

arch/riscv/kernel/traps_misaligned.c:361:21: warning: dereference of noderef expression
arch/riscv/kernel/traps_misaligned.c:373:21: warning: dereference of noderef expression
arch/riscv/kernel/traps_misaligned.c:381:21: warning: dereference of noderef expression
arch/riscv/kernel/traps_misaligned.c:322:24: warning: incorrect type in initializer (different address spaces)
arch/riscv/kernel/traps_misaligned.c:322:24:    expected unsigned char const [noderef] __user *__gu_ptr
arch/riscv/kernel/traps_misaligned.c:322:24:    got unsigned char const [usertype] *addr
arch/riscv/kernel/traps_misaligned.c:361:21: warning: dereference of noderef expression
arch/riscv/kernel/traps_misaligned.c:373:21: warning: dereference of noderef expression
arch/riscv/kernel/traps_misaligned.c:381:21: warning: dereference of noderef expression
arch/riscv/kernel/traps_misaligned.c:332:24: warning: incorrect type in initializer (different address spaces)
arch/riscv/kernel/traps_misaligned.c:332:24:    expected unsigned char [noderef] __user *__gu_ptr
arch/riscv/kernel/traps_misaligned.c:332:24:    got unsigned char [usertype] *addr

Fixes: 7c83232161 ("riscv: add support for misaligned trap handling in S-mode")
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Link: https://lore.kernel.org/r/20231123141617.259591-1-ben.dooks@codethink.co.uk
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-09 20:10:17 -08:00
Jisheng Zhang
cfbc4f81c9 riscv: Select ARCH_WANTS_NO_INSTR
As said in the help of ARCH_WANTS_NO_INSTR entry in arch/Kconfig:
"An architecture should select this if the noinstr macro is being used on
functions to denote that the toolchain should avoid instrumenting such
functions and is required for correctness."

Select ARCH_WANTS_NO_INSTR for correctness.

PS: The reason we didn't find any issue so far is that the
CC_HAS_NO_PROFILE_FN_ATTR is true.

Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Link: https://lore.kernel.org/r/20231123142223.1787-1-jszhang@kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-09 20:10:16 -08:00
Palmer Dabbelt
5634d9c280 Merge patch series "riscv: CPU operations cleanup"
Samuel Holland <samuel.holland@sifive.com> says:

This series cleans up some duplicated and dead code around the RISC-V
CPU operations, that was copied from arm64 but is not needed here. The
result is a bit of memory savings and removal of a few SBI calls during
boot, with no functional change.

* b4-shazam-merge:
  riscv: Use the same CPU operations for all CPUs
  riscv: Remove unused members from struct cpu_operations
  riscv: Deduplicate code in setup_smp()

Link: https://lore.kernel.org/r/20231121234736.3489608-1-samuel.holland@sifive.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-09 20:10:15 -08:00
Samuel Holland
b7b4e4d79f riscv: Remove obsolete rv32_defconfig file
This file is not used since commit 72f045d19f ("riscv: Fixup
difference with defconfig"), where it was replaced by the
32-bit.config fragment. Delete the old file to avoid any confusion.

Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20231121225320.3430550-1-samuel.holland@sifive.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-09 20:10:14 -08:00
Palmer Dabbelt
7a4749739c Merge patch series "RISC-V: hwprobe: Introduce which-cpus"
Andrew Jones <ajones@ventanamicro.com> says:

This series introduces a flag for the hwprobe syscall which effectively
reverses its behavior from getting the values of keys for a set of cpus
to getting the cpus for a set of key-value pairs.

* b4-shazam-merge:
  RISC-V: selftests: Add which-cpus hwprobe test
  RISC-V: hwprobe: Introduce which-cpus flag
  RISC-V: Move the hwprobe syscall to its own file
  RISC-V: hwprobe: Clarify cpus size parameter

Link: https://lore.kernel.org/r/20231122164700.127954-6-ajones@ventanamicro.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-09 20:10:13 -08:00
Frederik Haxel
6c4a2f6329 riscv: Allow disabling of BUILTIN_DTB for XIP
This enables, among other things, testing with the QEMU virt machine.

To build an XIP kernel for the QEMU virt machine, configure the
the kernel as desired and apply the following configuration
```
CONFIG_NONPORTABLE=y
CONFIG_XIP_KERNEL=y
CONFIG_XIP_PHYS_ADDR=0x20000000
CONFIG_PHYS_RAM_BASE=0x80200000
CONFIG_BUILTIN_DTB=n
```

Since the QEMU virt flash memory expects a 32 MB file, the built image
must be padded. For example, with
`truncate -s 32M arch/riscv/boot/xipImage`

The kernel can be started using the following command in QEMU (v8+)
```
qemu-system-riscv64 -M virt,pflash0=pflash0 \
 -blockdev node-name=pflash0,driver=file,read-only=on,\
filename=arch/riscv/boot/xipImage <optional parameters>
```

Signed-off-by: Frederik Haxel <haxel@fzi.de>
Link: https://lore.kernel.org/r/20231212130116.848530-4-haxel@fzi.de
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-09 19:33:22 -08:00
Frederik Haxel
5daa372641 riscv: Fixed wrong register in XIP_FIXUP_FLASH_OFFSET macro
During the refactoring, a bug was introduced in the rarly used
XIP_FIXUP_FLASH_OFFSET macro.

Fixes: bee7fbc385 ("RISC-V CPU Idle Support")
Fixes: e7681beba9 ("RISC-V: Split out the XIP fixups into their own file")

Signed-off-by: Frederik Haxel <haxel@fzi.de>
Link: https://lore.kernel.org/r/20231212130116.848530-3-haxel@fzi.de
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-09 19:33:21 -08:00
Frederik Haxel
66f1e68093 riscv: Make XIP bootable again
Currently, the XIP kernel seems to fail to boot due to missing
XIP_FIXUP and a wrong page_offset value. A superfluous XIP_FIXUP
has also been removed.

Signed-off-by: Frederik Haxel <haxel@fzi.de>
Link: https://lore.kernel.org/r/20231212130116.848530-2-haxel@fzi.de
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-09 19:33:20 -08:00
Alexandre Ghiti
b8b2711336 riscv: Fix set_direct_map_default_noflush() to reset _PAGE_EXEC
When resetting the linear mapping permissions, we must make sure that we
clear the X bit so that do not end up with WX mappings (since we set
PAGE_KERNEL).

Fixes: 395a21ff85 ("riscv: add ARCH_HAS_SET_DIRECT_MAP support")
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20231213134027.155327-3-alexghiti@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-09 10:59:08 -08:00
Alexandre Ghiti
749b94b080 riscv: Fix module_alloc() that did not reset the linear mapping permissions
After unloading a module, we must reset the linear mapping permissions,
see the example below:

Before unloading a module:

0xffffaf809d65d000-0xffffaf809d6dc000    0x000000011d65d000       508K PTE .   ..     ..   D A G . . W R V
0xffffaf809d6dc000-0xffffaf809d6dd000    0x000000011d6dc000         4K PTE .   ..     ..   D A G . . . R V
0xffffaf809d6dd000-0xffffaf809d6e1000    0x000000011d6dd000        16K PTE .   ..     ..   D A G . . W R V
0xffffaf809d6e1000-0xffffaf809d6e7000    0x000000011d6e1000        24K PTE .   ..     ..   D A G . X . R V

After unloading a module:

0xffffaf809d65d000-0xffffaf809d6e1000    0x000000011d65d000       528K PTE .   ..     ..   D A G . . W R V
0xffffaf809d6e1000-0xffffaf809d6e7000    0x000000011d6e1000        24K PTE .   ..     ..   D A G . X W R V

The last mapping is not reset and we end up with WX mappings in the linear
mapping.

So add VM_FLUSH_RESET_PERMS to our module_alloc() definition.

Fixes: 0cff8bff7a ("riscv: avoid the PIC offset of static percpu data in module beyond 2G limits")
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20231213134027.155327-2-alexghiti@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-09 10:59:07 -08:00
Alexandre Ghiti
c29fc621e1 riscv: Fix wrong usage of lm_alias() when splitting a huge linear mapping
lm_alias() can only be used on kernel mappings since it explicitly uses
__pa_symbol(), so simply fix this by checking where the address belongs
to before.

Fixes: 311cd2f6e2 ("riscv: Fix set_memory_XX() and set_direct_map_XX() by splitting huge linear mappings")
Reported-by: syzbot+afb726d49f84c8d95ee1@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/linux-riscv/000000000000620dd0060c02c5e1@google.com/
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Reviewed-by: Charlie Jenkins <charlie@rivosinc.com>
Link: https://lore.kernel.org/r/20231212195400.128457-1-alexghiti@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-09 10:59:06 -08:00
Alexandre Ghiti
420370f3ae riscv: Check if the code to patch lies in the exit section
Otherwise we fall through to vmalloc_to_page() which panics since the
address does not lie in the vmalloc region.

Fixes: 043cb41a85 ("riscv: introduce interfaces to patch kernel code")
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Reviewed-by: Charlie Jenkins <charlie@rivosinc.com>
Link: https://lore.kernel.org/r/20231214091926.203439-1-alexghiti@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-09 10:58:59 -08:00
Samuel Holland
62ff262227 riscv: Use the same CPU operations for all CPUs
RISC-V provides no binding (ACPI or DT) to describe per-cpu start/stop
operations, so cpu_set_ops() will always detect the same operations for
every CPU. Replace the cpu_ops array with a single pointer to save space
and reduce boot time.

Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20231121234736.3489608-4-samuel.holland@sifive.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-04 15:03:07 -08:00
Samuel Holland
79093f3ec3 riscv: Remove unused members from struct cpu_operations
name is not used anywhere at all. cpu_prepare and cpu_disable do nothing
and always return 0 if implemented.

Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20231121234736.3489608-3-samuel.holland@sifive.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-04 15:03:06 -08:00
Samuel Holland
a4166aec11 riscv: Deduplicate code in setup_smp()
Both the ACPI and DT implementations contain some of the same code.
Move it to the calling function so it is not duplicated.

Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20231121234736.3489608-2-samuel.holland@sifive.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-04 15:03:05 -08:00
Andrew Jones
ef7d6abb2c RISC-V: selftests: Add which-cpus hwprobe test
Test the RISCV_HWPROBE_WHICH_CPUS flag of hwprobe. The test also
has a command line interface in order to get the cpu list for
arbitrary hwprobe pairs.

Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Link: https://lore.kernel.org/r/20231122164700.127954-10-ajones@ventanamicro.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-03 03:36:50 -08:00
Andrew Jones
e178bf146e RISC-V: hwprobe: Introduce which-cpus flag
Introduce the first flag for the hwprobe syscall. The flag basically
reverses its behavior, i.e. instead of populating the values of keys
for a given set of cpus, the set of cpus after the call is the result
of finding a set which supports the values of the keys. In order to
do this, we implement a pair compare function which takes the type of
value (a single value vs. a bitmask of booleans) into consideration.
We also implement vdso support for the new flag.

Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Evan Green <evan@rivosinc.com>
Link: https://lore.kernel.org/r/20231122164700.127954-9-ajones@ventanamicro.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-03 03:36:49 -08:00
Andrew Jones
53b2b22850 RISC-V: Move the hwprobe syscall to its own file
As Palmer says, hwprobe is "sort of its own thing now, and it's only
going to get bigger..."

Suggested-by: Palmer Dabbelt <palmer@dabbelt.com>
Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20231122164700.127954-8-ajones@ventanamicro.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-03 03:36:48 -08:00
Andrew Jones
36d842d654 RISC-V: hwprobe: Clarify cpus size parameter
The "count" parameter associated with the 'cpus' parameter of the
hwprobe syscall is the size in bytes of 'cpus'. Naming it 'cpu_count'
may mislead users (it did me) to think it's the number of CPUs that
are or can be represented by 'cpus' instead. This is particularly
easy (IMO) to get wrong since 'cpus' is documented to be defined by
CPU_SET(3) and CPU_SET(3) also documents a CPU_COUNT() (the number
of CPUs in set) macro. CPU_SET(3) refers to the size of cpu sets
with 'setsize'. Adopt 'cpusetsize' for the hwprobe parameter and
specifically state it is in bytes in Documentation/riscv/hwprobe.rst
to clarify.

Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Link: https://lore.kernel.org/r/20231122164700.127954-7-ajones@ventanamicro.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-03 03:36:47 -08:00
Palmer Dabbelt
cbc911392c RISC-V: Remove the removed single-letter extensions
There were a few single-letter extensions that we had references to
floating around in the kernel, but that never ended up as actual ISA
specs and have mostly been replaced by multi-letter extensions.  This
removes the references to those extensions.

Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20231110175903.2631-1-palmer@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-03 03:28:49 -08:00
Palmer Dabbelt
e015eb628c Merge patch series "riscv: Use READ_ONCE()/WRITE_ONCE() for pte accesses"
Alexandre Ghiti <alexghiti@rivosinc.com> says:

This series is a follow-up for riscv of a recent series from Ryan [1] which
converts all direct dereferences of pte_t into a ptet_get() access.

The goal here for riscv is to use READ_ONCE()/WRITE_ONCE() for all page
table entries accesses to avoid any compiler transformation when the
hardware can concurrently modify the page tables entries (A/D bits for
example).

I went a bit further and added pud/p4d/pgd_get() helpers as such concurrent
modifications can happen too at those levels.

[1] https://lore.kernel.org/all/20230612151545.3317766-1-ryan.roberts@arm.com/

* b4-shazam-merge:
  riscv: Use accessors to page table entries instead of direct dereference
  riscv: mm: Only compile pgtable.c if MMU
  mm: Introduce pudp/p4dp/pgdp_get() functions
  riscv: Use WRITE_ONCE() when setting page table entries

Link: https://lore.kernel.org/r/20231213203001.179237-1-alexghiti@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-12-20 10:48:17 -08:00
Alexandre Ghiti
edf9556472 riscv: Use accessors to page table entries instead of direct dereference
As very well explained in commit 20a004e7b0 ("arm64: mm: Use
READ_ONCE/WRITE_ONCE when accessing page tables"), an architecture whose
page table walker can modify the PTE in parallel must use
READ_ONCE()/WRITE_ONCE() macro to avoid any compiler transformation.

So apply that to riscv which is such architecture.

Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Acked-by: Anup Patel <anup@brainfault.org>
Link: https://lore.kernel.org/r/20231213203001.179237-5-alexghiti@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-12-20 10:48:15 -08:00
Alexandre Ghiti
d6508999d1 riscv: mm: Only compile pgtable.c if MMU
All functions defined in there depend on MMU, so no need to compile it
for !MMU configs.

Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20231213203001.179237-4-alexghiti@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-12-20 10:48:14 -08:00
Alexandre Ghiti
eba2591d99 mm: Introduce pudp/p4dp/pgdp_get() functions
Instead of directly dereferencing page tables entries, which can cause
issues (see commit 20a004e7b0 ("arm64: mm: Use READ_ONCE/WRITE_ONCE when
accessing page tables"), let's introduce new functions to get the
pud/p4d/pgd entries (the pte and pmd versions already exist).

Note that arm pgd_t is actually an array so pgdp_get() is defined as a
macro to avoid a build error.

Those new functions will be used in subsequent commits by the riscv
architecture.

Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20231213203001.179237-3-alexghiti@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-12-20 10:48:13 -08:00
Alexandre Ghiti
c30fa83b49 riscv: Use WRITE_ONCE() when setting page table entries
To avoid any compiler "weirdness" when accessing page table entries which
are concurrently modified by the HW, let's use WRITE_ONCE() macro
(commit 20a004e7b0 ("arm64: mm: Use READ_ONCE/WRITE_ONCE when accessing
page tables") gives a great explanation with more details).

Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20231213203001.179237-2-alexghiti@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-12-20 10:48:12 -08:00
Michal Simek
4a6b93f562 dt-bindings: riscv: cpus: Add AMD MicroBlaze V compatible
MicroBlaze V is new AMD/Xilinx soft-core 32bit RISC-V processor IP.
It is hardware compatible with classic MicroBlaze processor.

Signed-off-by: Michal Simek <michal.simek@amd.com>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/d442d916204d26f82c1c3a924a4cdfb117960e1b.1699270661.git.michal.simek@amd.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-12-20 07:15:00 -08:00
Palmer Dabbelt
f352a28cc2 Merge patch series "riscv: report more ISA extensions through hwprobe"
Clément Léger <cleger@rivosinc.com> says:

In order to be able to gather more information about the supported ISA
extensions from userspace using the hwprobe syscall, add more ISA
extensions report. This series adds the following ISA extensions parsing
support:

- Zfh[min]
- Zvfh[min]
- Zihintntl
- Zbc
- Zvbb
- Zvbc
- Zvkb
- Zvkg
- Zvkned
- Zvknh[ab]
- Zvksed
- Zvksh
- Zvkn
- Zvknc
- Zvkng
- Zvks
- Zvksc
- Zvksg
- Zvkt
- Zfa
- Zbkb
- Zbkc
- Zbkx
- Zknd
- Zkne
- Zknh
- Zkr
- Zksed
- Zksh
- Zkt

Some of these extensions are actually shorthands for other "sub"
extensions. This series includes a patch from Conor/Evan that adds a way
to specify such "bundled" extensions. When exposing these bundled
extensions to userspace through hwprobe, only the "sub" extensions are
exposed.

In order to test it, one can use qemu and the small hwprobe utility
provided[1]. Run qemu by specifying additional ISA extensions, for
instance:

$ qemu-system-riscv64 -cpu rv64,v=true,zk=true,zvksh=true,zvkned=true
  <whatever options you want>

Then, run hwprobe:

$ ./hwprobe
Base system ISA:
 - IMA_FD
 - C
 - V
Supported extensions:
 - Zba
 - Zbb
 - Zbs
 - Zbc
 - Zbkb
 - Zbkc
 - Zbkx
 - Zknd
 - Zkne
 - Zknh
 - Zkt
 - Zvkned
 - Zvksh
 - Zihintntl
 - Zfa

* b4-shazam-merge:
  dt-bindings: riscv: add Zfa ISA extension description
  riscv: hwprobe: export Zfa ISA extension
  riscv: add ISA extension parsing for Zfa
  dt-bindings: riscv: add Zvfh[min] ISA extension description
  riscv: hwprobe: export Zvfh[min] ISA extensions
  riscv: add ISA extension parsing for Zvfh[min]
  dt-bindings: riscv: add Zihintntl ISA extension description
  riscv: hwprobe: export Zhintntl ISA extension
  riscv: add ISA extension parsing for Zihintntl
  dt-bindings: riscv: add Zfh[min] ISA extensions description
  riscv: hwprobe: export Zfh[min] ISA extensions
  riscv: add ISA extension parsing for Zfh/Zfh[min]
  dt-bindings: riscv: add vector crypto ISA extensions description
  riscv: hwprobe: export vector crypto ISA extensions
  riscv: add ISA extension parsing for vector crypto
  dt-bindings: riscv: add scalar crypto ISA extensions description
  riscv: hwprobe: add support for scalar crypto ISA extensions
  riscv: add ISA extension parsing for scalar crypto
  riscv: hwprobe: export missing Zbc ISA extension
  riscv: add ISA extension parsing for Zbc

Link: https://lore.kernel.org/r/20231114141256.126749-1-cleger@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-12-12 15:45:18 -08:00
Clément Léger
9726acfdfa dt-bindings: riscv: add Zfa ISA extension description
Add description for the Zfa ISA extension[1].

Link: https://drive.google.com/file/d/1VT6QIggpb59-8QRV266dEE4T8FZTxGq4/view [1]
Signed-off-by: Clément Léger <cleger@rivosinc.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20231114141256.126749-21-cleger@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-12-12 15:45:17 -08:00
Clément Léger
dc6ccb21f4 riscv: hwprobe: export Zfa ISA extension
Export Zfa ISA extension[1] through hwprobe.

Link: https://drive.google.com/file/d/1VT6QIggpb59-8QRV266dEE4T8FZTxGq4/view [1]
Signed-off-by: Clément Léger <cleger@rivosinc.com>
Reviewed-by: Evan Green <evan@rivosinc.com>
Link: https://lore.kernel.org/r/20231114141256.126749-20-cleger@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-12-12 15:45:16 -08:00
Clément Léger
fe987e84b0 riscv: add ISA extension parsing for Zfa
Add parsing for Zfa ISA extension [1] which were ratified in commit
056b6ff467c7 ("Zfa is ratified") of riscv-isa-manual[2].

Link: https://drive.google.com/file/d/1VT6QIggpb59-8QRV266dEE4T8FZTxGq4/view [1]
Link: https://github.com/riscv/riscv-isa-manual/commits/056b6ff467c7 [2]
Signed-off-by: Clément Léger <cleger@rivosinc.com>
Reviewed-by: Evan Green <evan@rivosinc.com>
Link: https://lore.kernel.org/r/20231114141256.126749-19-cleger@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-12-12 15:45:15 -08:00
Clément Léger
e11880b4be dt-bindings: riscv: add Zvfh[min] ISA extension description
Add description for Zvfh[min] ISA extension[1].

Link: https://drive.google.com/file/d/1_Yt60HGAf1r1hx7JnsIptw0sqkBd9BQ8/view [1]
Signed-off-by: Clément Léger <cleger@rivosinc.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20231114141256.126749-18-cleger@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-12-12 15:45:14 -08:00
Clément Léger
5dadda5e6a riscv: hwprobe: export Zvfh[min] ISA extensions
Export Zvfh[min] ISA extension[1] through hwprobe.

Link: https://drive.google.com/file/d/1_Yt60HGAf1r1hx7JnsIptw0sqkBd9BQ8/view [1]
Signed-off-by: Clément Léger <cleger@rivosinc.com>
Reviewed-by: Evan Green <evan@rivosinc.com>
Link: https://lore.kernel.org/r/20231114141256.126749-17-cleger@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-12-12 15:45:13 -08:00
Clément Léger
f4961b78c3 riscv: add ISA extension parsing for Zvfh[min]
Add parsing for Zvfh[min] ISA extension[1] which were ratified in
june 2023 around commit e2ccd0548d6c ("Remove draft warnings from
Zvfh[min]") in riscv-v-spec[2].

Link: https://drive.google.com/file/d/1_Yt60HGAf1r1hx7JnsIptw0sqkBd9BQ8/view [1]
Link: https://github.com/riscv/riscv-v-spec/commits/e2ccd0548d6c [2]
Signed-off-by: Clément Léger <cleger@rivosinc.com>
Reviewed-by: Evan Green <evan@rivosinc.com>
Link: https://lore.kernel.org/r/20231114141256.126749-16-cleger@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-12-12 15:45:12 -08:00
Clément Léger
892f10c8d6 dt-bindings: riscv: add Zihintntl ISA extension description
Add description for Zihintntl ISA extension[1].

Link: https://drive.google.com/file/d/13_wsN8YmRfH8YWysFyTX-DjTkCnBd9hj/view [1]
Signed-off-by: Clément Léger <cleger@rivosinc.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20231114141256.126749-15-cleger@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-12-12 15:45:11 -08:00
Clément Léger
74ba42b250 riscv: hwprobe: export Zhintntl ISA extension
Export Zihintntl extension[1] through hwprobe.

Link: https://drive.google.com/file/d/13_wsN8YmRfH8YWysFyTX-DjTkCnBd9hj/view [1]
Signed-off-by: Clément Léger <cleger@rivosinc.com>
Reviewed-by: Evan Green <evan@rivosinc.com>
Link: https://lore.kernel.org/r/20231114141256.126749-14-cleger@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-12-12 15:45:10 -08:00
Clément Léger
eddbfa0d84 riscv: add ISA extension parsing for Zihintntl
Add parsing for Zihintntl ISA extension[1] that was ratified in commit
0dc91f5 ("Zihintntl is ratified") of riscv-isa-manual[2].

Link: https://drive.google.com/file/d/13_wsN8YmRfH8YWysFyTX-DjTkCnBd9hj/view [1]
Link: https://github.com/riscv/riscv-isa-manual/commit/0dc91f505e6d [2]
Signed-off-by: Clément Léger <cleger@rivosinc.com>
Reviewed-by: Evan Green <evan@rivosinc.com>
Link: https://lore.kernel.org/r/20231114141256.126749-13-cleger@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-12-12 15:45:09 -08:00
Clément Léger
c44714c35f dt-bindings: riscv: add Zfh[min] ISA extensions description
Add description of Zfh[min] ISA extensions[1].

Link: https://drive.google.com/file/d/1z3tQQLm5ALsAD77PM0l0CHnapxWCeVzP/view [1]
Signed-off-by: Clément Léger <cleger@rivosinc.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20231114141256.126749-12-cleger@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-12-12 15:45:08 -08:00
Clément Léger
bf4cd84111 riscv: hwprobe: export Zfh[min] ISA extensions
Export Zfh[min] ISA extensions[1] through hwprobe only if FPU support
is available.

Link: https://drive.google.com/file/d/1z3tQQLm5ALsAD77PM0l0CHnapxWCeVzP/view [1]
Signed-off-by: Clément Léger <cleger@rivosinc.com>
Reviewed-by: Evan Green <evan@rivosinc.com>
Link: https://lore.kernel.org/r/20231114141256.126749-11-cleger@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-12-12 15:45:07 -08:00