[PATCH v3 0/4] riscv: Separate vendor extensions from standard extensions

[Charlie Jenkins]

All extensions, both standard and vendor, live in one struct
"riscv_isa_ext". There is currently one vendor extension, xandespmu, but
it is likely that more vendor extensions will be added to the kernel in
the future. As more vendor extensions (and standard extensions) are
added, riscv_isa_ext will become more bloated with a mix of vendor and
standard extensions.

This also allows each vendor to be conditionally enabled through
Kconfig.

---
This has been split out from the previous series that contained the
addition of xtheadvector due to lack of reviews. The xtheadvector
support will be posted again separately from this.

The alternative patching code from "riscv: Introduce vendor variants of
extension helpers" has been migrated to "riscv: Extend cpufeature.c to
detect vendor extensions" such that the andes patching still works in
that patch.

I also fix a bug in this patch from the previous series that the Andes
extensions were not being properly enabled due to the manual alternative
patching not incrementing the id to be greater than
RISCV_VENDOR_EXT_ALTERNATIVES_BASE. 

To: Paul Walmsley <paul.walmsley at sifive.com>
To: Palmer Dabbelt <palmer at dabbelt.com>
To: Albert Ou <aou at eecs.berkeley.edu>
To: Conor Dooley <conor.dooley at microchip.com>
To: Evan Green <evan at rivosinc.com>
To: Andy Chiu <andy.chiu at sifive.com>
Cc: linux-riscv at lists.infradead.org
Cc: linux-kernel at vger.kernel.org
Signed-off-by: Charlie Jenkins <charlie at rivosinc.com>

---
Changes in v3:
- Rebase onto for-next as there have been a lot of upstream changes!
- Link to v2: https://lore.kernel.org/r/20240609-support_vendor_extensions-v2-0-9a43f1fdcbb9@rivosinc.com

Changes in v2:
- Fixed issue in riscv_fill_vendor_ext_list() that initalizion was only
  happening properly for the first vendor. Add is_initialized field to
  riscv_isa_vendor_ext_data_list to allow intialization to be tracked on
  a per-vendor basis.
- Link to v1: https://lore.kernel.org/r/20240515-support_vendor_extensions-v1-0-b05dd5ea7d8d@rivosinc.com

---
Charlie Jenkins (4):
      riscv: Extend cpufeature.c to detect vendor extensions
      riscv: Add vendor extensions to /proc/cpuinfo
      riscv: Introduce vendor variants of extension helpers
      riscv: cpufeature: Extract common elements from extension checking

 arch/riscv/Kconfig                               |   2 +
 arch/riscv/Kconfig.vendor                        |  19 +++
 arch/riscv/errata/andes/errata.c                 |   3 +
 arch/riscv/errata/sifive/errata.c                |   3 +
 arch/riscv/errata/thead/errata.c                 |   3 +
 arch/riscv/include/asm/cpufeature.h              | 103 ++++++++++------
 arch/riscv/include/asm/hwcap.h                   |  25 ++--
 arch/riscv/include/asm/vendor_extensions.h       | 104 +++++++++++++++++
 arch/riscv/include/asm/vendor_extensions/andes.h |  19 +++
 arch/riscv/kernel/Makefile                       |   2 +
 arch/riscv/kernel/cpu.c                          |  35 +++++-
 arch/riscv/kernel/cpufeature.c                   | 143 ++++++++++++++++-------
 arch/riscv/kernel/vendor_extensions.c            |  56 +++++++++
 arch/riscv/kernel/vendor_extensions/Makefile     |   3 +
 arch/riscv/kernel/vendor_extensions/andes.c      |  18 +++
 drivers/perf/riscv_pmu_sbi.c                     |  11 +-
 16 files changed, 456 insertions(+), 93 deletions(-)
---
base-commit: 41c196e567fb1ea97f68a2ffb7faab451cd90854
change-id: 20240515-support_vendor_extensions-aa80120e4230
-- 
- Charlie