[PATCH 4/5] include: sbi: Few cosmetic changes in riscv_encoding.h

[Anup Patel]

> -----Original Message-----
> From: Heinrich Schuchardt <xypron.glpk at gmx.de>
> Sent: 22 August 2020 14:02
> To: Anup Patel <Anup.Patel at wdc.com>; Atish Patra
> <Atish.Patra at wdc.com>; Alistair Francis <Alistair.Francis at wdc.com>
> Cc: Anup Patel <anup at brainfault.org>; opensbi at lists.infradead.org
> Subject: Re: [PATCH 4/5] include: sbi: Few cosmetic changes in
> riscv_encoding.h
> 
> On 8/22/20 7:13 AM, Anup Patel wrote:
> > This patch does few cosmentic changes to riscv_encoding.h:
> > 1. Place CSR_CYCLE define close to CSR_HPMCOUNTERx defines 2. Rename
> > CSR_HCOUNTERNEN to CSR_HCOUNTEREN
> >
> > Signed-off-by: Anup Patel <anup.patel at wdc.com>
> > ---
> >  include/sbi/riscv_encoding.h | 4 ++--
> >  1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/include/sbi/riscv_encoding.h
> > b/include/sbi/riscv_encoding.h index 073261f..bb7eb88 100644
> > --- a/include/sbi/riscv_encoding.h
> > +++ b/include/sbi/riscv_encoding.h
> > @@ -175,7 +175,6 @@
> >  #define CSR_FFLAGS			0x1
> 
> The "The RISC-V Instruction Set ManualVolume II: Privileged Architecture
> Document Version 20190608" always uses three digits (0x001). For looking up
> the definitions it would be preferable to do the same here.

Good suggestion. I will update all CSR defines to be three digits.

> 
> >  #define CSR_FRM				0x2
> >  #define CSR_FCSR			0x3
> > -#define CSR_CYCLE			0xc00
> >  #define CSR_UIE				0x4
> >  #define CSR_UTVEC			0x5
> >  #define CSR_USCRATCH			0x40
> > @@ -183,6 +182,7 @@
> >  #define CSR_UCAUSE			0x42
> >  #define CSR_UTVAL			0x43
> >  #define CSR_UIP				0x44
> > +#define CSR_CYCLE			0xc00
> >  #define CSR_TIME			0xc01
> >  #define CSR_INSTRET			0xc02
> >  #define CSR_HPMCOUNTER3			0xc03
> > @@ -231,7 +231,7 @@
> >  #define CSR_HIE				0x604
> >  #define CSR_HTIMEDELTA			0x605
> >  #define CSR_HTIMEDELTAH			0x615
> > -#define CSR_HCOUNTERNEN			0x606
> > +#define CSR_HCOUNTEREN			0x606
> 
> Why do you put 0x606 after 0x615? And why is the 0x600 group before
> 0x200 but after 0xc00.

The CSR defines are not in any particular aligned.

Let me arrange them as defined in RISC-V spec.

> 
> Where are the 0x6xx values taken from? I can't find them in aforementioned
> spec? Links to the reference documents as comments in the include would
> be helpful to look up the meaning of the different CSRs.

The 0x6xx CSRs are part of the RISC-V H-extension draft spec.

You will see these CSRs if you manually build latest riscv-isa-manual.

Regards,
Anup