[PATCH v6 0/5] drivers/soc/litex: support 32-bit subregisters, 64-bit CPUs

From: Gabriel Somlo
Date: Tue Jan 12 2021 - 12:33:04 EST


This series expands on commit 22447a99c97e ("drivers/soc/litex: add LiteX
SoC Controller driver"), adding support for handling both 8- and 32-bit
LiteX CSR (MMIO) subregisters, on both 32- and 64-bit CPUs.

Notes v6:
- split out s/LITEX_REG_SIZE/LITEX_SUBREG_ALIGN/g change
into its own dedicated (cosmetic-only) patch (3/5).
- fixed typos in "main patch" (now 4/5) changelog.
- fixed typos in comments added via patch 5/5.

Notes v5:
- added patch (4/4) taking 'litex_[set|get]_reg()' private
- additional optimization of [_]litex_set_reg() in 3/4

Notes v4:
- improved "eloquence" of some 3/3 commit blurb paragraphs
- fixed instance of "disgusting" comment style :)
- litex_[get|set]_reg() now using size_t for 'reg_size' argument
- slightly tighter shift calculation in litex_set_reg()

Notes v3:
- split into smaller, more self-explanatory patches
- more detailed commit blurb for "main payload" (3/3) patch
- eliminate compiler warning on 32-bit architectures

Notes v2:
- fix typo (s/u32/u64/) in litex_read64().

Notes v1:
- LITEX_SUBREG_SIZE now provided by Kconfig.
- it's not LITEX_REG_SIZE, but rather LITEX_SUBREG_ALIGN!
- move litex_[get|set]_reg() to include/linux/litex.h and mark
them as "static inline";
- redo litex_[read|write][8|16|32|64]() using litex_[get|set]_reg()
(compiler should produce code as efficient as hardcoded shifts,
but also automatically matching LITEX_SUBREG_SIZE).

Gabriel Somlo (5):
drivers/soc/litex: move generic accessors to litex.h
drivers/soc/litex: separate MMIO from subregister offset calculation
drivers/soc/litex: rename LITEX_REG_SIZE to LITEX_SUBREG_ALIGN
drivers/soc/litex: support 32-bit subregisters, 64-bit CPUs
drivers/soc/litex: make 'litex_[set|get]_reg()' methods private

drivers/soc/litex/Kconfig | 14 ++-
drivers/soc/litex/litex_soc_ctrl.c | 76 +-------------
include/linux/litex.h | 154 +++++++++++++++++++----------
3 files changed, 119 insertions(+), 125 deletions(-)

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2.26.2