Re: [PATCH 1/7] RISC-V: Add AIA related CSR defines

From: Andrew Jones
Date: Thu Jan 26 2023 - 10:48:01 EST


On Thu, Jan 12, 2023 at 07:32:58PM +0530, Anup Patel wrote:
> The RISC-V AIA specification improves handling per-HART local interrupts
> in a backward compatible manner. This patch adds defines for new RISC-V
> AIA CSRs.
>
> Signed-off-by: Anup Patel <apatel@xxxxxxxxxxxxxxxx>
> ---
> arch/riscv/include/asm/csr.h | 93 ++++++++++++++++++++++++++++++++++++
> 1 file changed, 93 insertions(+)
>
> diff --git a/arch/riscv/include/asm/csr.h b/arch/riscv/include/asm/csr.h
> index 0e571f6483d9..d608dac4b19f 100644
> --- a/arch/riscv/include/asm/csr.h
> +++ b/arch/riscv/include/asm/csr.h
> @@ -73,7 +73,10 @@
> #define IRQ_S_EXT 9
> #define IRQ_VS_EXT 10
> #define IRQ_M_EXT 11
> +#define IRQ_S_GEXT 12
> #define IRQ_PMU_OVF 13
> +#define IRQ_LOCAL_MAX (IRQ_PMU_OVF + 1)
> +#define IRQ_LOCAL_MASK ((_AC(1, UL) << IRQ_LOCAL_MAX) - 1)

How about instead of the above two defines we do

#define IRQ_LOCAL_MASK GENMASK(13, 0)

And in general it might be nice to put GENMASK to work for all the
new masks below.

>
> /* Exception causes */
> #define EXC_INST_MISALIGNED 0
> @@ -156,6 +159,27 @@
> (_AC(1, UL) << IRQ_S_TIMER) | \
> (_AC(1, UL) << IRQ_S_EXT))
>
> +/* AIA CSR bits */
> +#define TOPI_IID_SHIFT 16
> +#define TOPI_IID_MASK _AC(0xfff, UL)
> +#define TOPI_IPRIO_MASK _AC(0xff, UL)
> +#define TOPI_IPRIO_BITS 8
> +
> +#define TOPEI_ID_SHIFT 16
> +#define TOPEI_ID_MASK _AC(0x7ff, UL)
> +#define TOPEI_PRIO_MASK _AC(0x7ff, UL)
> +
> +#define ISELECT_IPRIO0 0x30
> +#define ISELECT_IPRIO15 0x3f
> +#define ISELECT_MASK _AC(0x1ff, UL)
> +
> +#define HVICTL_VTI _AC(0x40000000, UL)

I'd rather read this as '1 << 30' to match the spec and other
bit masks in this file. Actually, it'd be nice if BIT() was
used throughout this file, e.g. #define HVICTL_VTI BIT(30)

> +#define HVICTL_IID _AC(0x0fff0000, UL)
> +#define HVICTL_IID_SHIFT 16
> +#define HVICTL_DPR _AC(0x00000200, UL)
> +#define HVICTL_IPRIOM _AC(0x00000100, UL)
> +#define HVICTL_IPRIO _AC(0x000000ff, UL)
> +
> /* xENVCFG flags */
> #define ENVCFG_STCE (_AC(1, ULL) << 63)
> #define ENVCFG_PBMTE (_AC(1, ULL) << 62)
> @@ -250,6 +274,18 @@
> #define CSR_STIMECMP 0x14D
> #define CSR_STIMECMPH 0x15D
>
> +/* Supervisor-Level Window to Indirectly Accessed Registers (AIA) */
> +#define CSR_SISELECT 0x150
> +#define CSR_SIREG 0x151
> +
> +/* Supervisor-Level Interrupts (AIA) */
> +#define CSR_STOPEI 0x15c
> +#define CSR_STOPI 0xdb0
> +
> +/* Supervisor-Level High-Half CSRs (AIA) */
> +#define CSR_SIEH 0x114
> +#define CSR_SIPH 0x154
> +
> #define CSR_VSSTATUS 0x200
> #define CSR_VSIE 0x204
> #define CSR_VSTVEC 0x205
> @@ -279,8 +315,32 @@
> #define CSR_HGATP 0x680
> #define CSR_HGEIP 0xe12
>
> +/* Virtual Interrupts and Interrupt Priorities (H-extension with AIA) */
> +#define CSR_HVIEN 0x608
> +#define CSR_HVICTL 0x609
> +#define CSR_HVIPRIO1 0x646
> +#define CSR_HVIPRIO2 0x647
> +
> +/* VS-Level Window to Indirectly Accessed Registers (H-extension with AIA) */
> +#define CSR_VSISELECT 0x250
> +#define CSR_VSIREG 0x251
> +
> +/* VS-Level Interrupts (H-extension with AIA) */
> +#define CSR_VSTOPEI 0x25c
> +#define CSR_VSTOPI 0xeb0
> +
> +/* Hypervisor and VS-Level High-Half CSRs (H-extension with AIA) */
> +#define CSR_HIDELEGH 0x613
> +#define CSR_HVIENH 0x618
> +#define CSR_HVIPH 0x655
> +#define CSR_HVIPRIO1H 0x656
> +#define CSR_HVIPRIO2H 0x657
> +#define CSR_VSIEH 0x214
> +#define CSR_VSIPH 0x254
> +
> #define CSR_MSTATUS 0x300
> #define CSR_MISA 0x301
> +#define CSR_MIDELEG 0x303
> #define CSR_MIE 0x304
> #define CSR_MTVEC 0x305
> #define CSR_MENVCFG 0x30a
> @@ -297,6 +357,25 @@
> #define CSR_MIMPID 0xf13
> #define CSR_MHARTID 0xf14
>
> +/* Machine-Level Window to Indirectly Accessed Registers (AIA) */
> +#define CSR_MISELECT 0x350
> +#define CSR_MIREG 0x351
> +
> +/* Machine-Level Interrupts (AIA) */
> +#define CSR_MTOPEI 0x35c
> +#define CSR_MTOPI 0xfb0
> +
> +/* Virtual Interrupts for Supervisor Level (AIA) */
> +#define CSR_MVIEN 0x308
> +#define CSR_MVIP 0x309
> +
> +/* Machine-Level High-Half CSRs (AIA) */
> +#define CSR_MIDELEGH 0x313
> +#define CSR_MIEH 0x314
> +#define CSR_MVIENH 0x318
> +#define CSR_MVIPH 0x319
> +#define CSR_MIPH 0x354
> +
> #ifdef CONFIG_RISCV_M_MODE
> # define CSR_STATUS CSR_MSTATUS
> # define CSR_IE CSR_MIE
> @@ -307,6 +386,13 @@
> # define CSR_TVAL CSR_MTVAL
> # define CSR_IP CSR_MIP
>
> +# define CSR_IEH CSR_MIEH
> +# define CSR_ISELECT CSR_MISELECT
> +# define CSR_IREG CSR_MIREG
> +# define CSR_IPH CSR_MIPH
> +# define CSR_TOPEI CSR_MTOPEI
> +# define CSR_TOPI CSR_MTOPI
> +
> # define SR_IE SR_MIE
> # define SR_PIE SR_MPIE
> # define SR_PP SR_MPP
> @@ -324,6 +410,13 @@
> # define CSR_TVAL CSR_STVAL
> # define CSR_IP CSR_SIP
>
> +# define CSR_IEH CSR_SIEH
> +# define CSR_ISELECT CSR_SISELECT
> +# define CSR_IREG CSR_SIREG
> +# define CSR_IPH CSR_SIPH
> +# define CSR_TOPEI CSR_STOPEI
> +# define CSR_TOPI CSR_STOPI
> +
> # define SR_IE SR_SIE
> # define SR_PIE SR_SPIE
> # define SR_PP SR_SPP
> --
> 2.34.1
>

Besides my preference for GENMASK and BIT, this looks good to me.

Reviewed-by: Andrew Jones <ajones@xxxxxxxxxxxxxxxx>

Thanks,
drew