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* [PATCH v4 0/6] Provide a fraemework for RISC-V ISA extensions
@ 2022-02-16  0:29 ` Atish Patra
  0 siblings, 0 replies; 28+ messages in thread
From: Atish Patra @ 2022-02-16  0:29 UTC (permalink / raw)
  To: linux-kernel
  Cc: Atish Patra, Albert Ou, Atish Patra, Anup Patel, Damien Le Moal,
	devicetree, Jisheng Zhang, Krzysztof Kozlowski, linux-riscv,
	Palmer Dabbelt, Paul Walmsley, heiko, Rob Herring

This series implements a generic framework to parse multi-letter ISA
extensions. This series is based on Tsukasa's v3 isa extension improvement
series[1]. I have fixed few bugs and improved comments from that series
(PATCH1-3). I have not used PATCH 4 from that series as we are not using
ISA extension versioning as of now. We can add that later if required.

PATCH 4 allows the probing of multi-letter extensions via a macro.
It continues to use the common isa extensions between all the harts.
Thus hetergenous hart systems will only see the common ISA extensions.

PATCH 6 improves the /proc/cpuinfo interface for the available ISA extensions
via /proc/cpuinfo.

Here is the example output of /proc/cpuinfo:
(with debug patches in Qemu and Linux kernel)

/ # cat /proc/cpuinfo
processor	: 0
hart		: 0
isa		: rv64imafdcsu
isa-ext		: sstc,sscofpmf
mmu		: sv48

processor	: 1
hart		: 1
isa		: rv64imafdcsu
isa-ext		: sstc,sscofpmf
mmu		: sv48

processor	: 2
hart		: 2
isa		: rv64imafdcsu
isa-ext		: sstc,sscofpmf
mmu		: sv48

processor	: 3
hart		: 3
isa		: rv64imafdcsu
isa-ext		: sstc,sscofpmf
mmu		: sv48

Anybody adding support for any new multi-letter extensions should add an
entry to the riscv_isa_ext_id and the isa extension array. 
E.g. The patch[2] adds the support for various ISA extensions.

[1] https://lore.kernel.org/all/0f568515-a05e-8204-aae3-035975af3ee8@irq.a4lg.com/T/
[2] https://github.com/atishp04/linux/commit/e9e240c9a854dceb434ceb53bdbe82a657bee5f2 


Changes from v3->v4:
1. Changed temporary variable for current hart isa to a bitmap
2. Added reviewed-by tags.
3. Improved comments

Changes from v2->v3:
1. Updated comments to mark clearly a fix required for Qemu only.
2. Fixed a bug where the 1st multi-letter extension can be present without _
3. Added Tested by tags. 

Changes from v1->v2:
1. Instead of adding a separate DT property use the riscv,isa property.
2. Based on Tsukasa's v3 isa extension improvement series.

Atish Patra (3):
RISC-V: Implement multi-letter ISA extension probing framework
RISC-V: Do no continue isa string parsing without correct XLEN
RISC-V: Improve /proc/cpuinfo output for ISA extensions

Tsukasa OI (3):
RISC-V: Correctly print supported extensions
RISC-V: Minimal parser for "riscv, isa" strings
RISC-V: Extract multi-letter extension names from "riscv, isa"

arch/riscv/include/asm/hwcap.h |  25 +++++++
arch/riscv/kernel/cpu.c        |  44 +++++++++++-
arch/riscv/kernel/cpufeature.c | 125 +++++++++++++++++++++++++++------
3 files changed, 171 insertions(+), 23 deletions(-)

--
2.30.2


^ permalink raw reply	[flat|nested] 28+ messages in thread

end of thread, other threads:[~2022-02-22 18:11 UTC | newest]

Thread overview: 28+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-02-16  0:29 [PATCH v4 0/6] Provide a fraemework for RISC-V ISA extensions Atish Patra
2022-02-16  0:29 ` Atish Patra
2022-02-16  0:29 ` [PATCH v4 1/6] RISC-V: Correctly print supported extensions Atish Patra
2022-02-16  0:29   ` Atish Patra
2022-02-16  0:29 ` [PATCH v4 2/6] RISC-V: Minimal parser for "riscv, isa" strings Atish Patra
2022-02-16  0:29   ` Atish Patra
2022-02-16  0:29 ` [PATCH v4 3/6] RISC-V: Extract multi-letter extension names from "riscv, isa" Atish Patra
2022-02-16  0:29   ` Atish Patra
2022-02-16  0:29 ` [PATCH v4 4/6] RISC-V: Implement multi-letter ISA extension probing framework Atish Patra
2022-02-16  0:29   ` Atish Patra
2022-02-16 11:43   ` Heiko Stübner
2022-02-16 11:43     ` Heiko Stübner
2022-02-16  0:29 ` [PATCH v4 5/6] RISC-V: Do no continue isa string parsing without correct XLEN Atish Patra
2022-02-16  0:29   ` Atish Patra
2022-02-16 11:46   ` Heiko Stübner
2022-02-16 11:46     ` Heiko Stübner
2022-02-16  0:29 ` [PATCH v4 6/6] RISC-V: Improve /proc/cpuinfo output for ISA extensions Atish Patra
2022-02-16  0:29   ` Atish Patra
2022-02-16 11:46   ` Heiko Stübner
2022-02-16 11:46     ` Heiko Stübner
2022-02-16  5:04 ` [PATCH 0/2] RISC-V: some improvements for Atish's framework (for v5) Tsukasa OI
2022-02-16  5:04   ` [PATCH 1/2] RISC-V: Better 'S' workaround Tsukasa OI
2022-02-16  5:04   ` [PATCH 2/2] RISC-V: Extract base ISA from device tree Tsukasa OI
2022-02-16  6:01     ` Atish Patra
2022-02-16  6:58       ` Tsukasa OI
2022-02-16  7:43         ` Atish Patra
2022-02-21 13:42           ` Tsukasa OI
2022-02-22 18:10             ` Atish Patra

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