Re: [PATCH 01/12] riscv: abstract out CSR names for supervisor vs machine mode

Paul Walmsley
2019-11-05T17:56:09Z

Daniel, Thomas,

On Mon, 28 Oct 2019, Christoph Hellwig wrote:

> Many of the privileged CSRs exist in a supervisor and machine version
> that are used very similarly. Provide versions of the CSR names and
> fields that map to either the S-mode or M-mode variant depending on
> a new CONFIG_RISCV_M_MODE kconfig symbol.
>
> Contains contributions from Damien Le Moal <Damien.LeMoal@wdc.com>
> and Paul Walmsley <paul.walmsley@sifive.com>.

Care to give a quick ack to the drivers/clocksource/timer-riscv.c changes?

thanks,

- Paul

>
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> ---
> arch/riscv/Kconfig | 4 ++
> arch/riscv/include/asm/csr.h | 72 +++++++++++++++++++++++++----
> arch/riscv/include/asm/irqflags.h | 12 ++---
> arch/riscv/include/asm/processor.h | 2 +-
> arch/riscv/include/asm/ptrace.h | 16 +++----
> arch/riscv/include/asm/switch_to.h | 10 ++--
> arch/riscv/kernel/asm-offsets.c | 8 ++--
> arch/riscv/kernel/entry.S | 74 +++++++++++++++++-------------
> arch/riscv/kernel/fpu.S | 8 ++--
> arch/riscv/kernel/head.S | 12 ++---
> arch/riscv/kernel/irq.c | 17 ++-----
> arch/riscv/kernel/perf_callchain.c | 2 +-
> arch/riscv/kernel/process.c | 17 +++----
> arch/riscv/kernel/signal.c | 21 ++++-----
> arch/riscv/kernel/smp.c | 2 +-
> arch/riscv/kernel/traps.c | 16 +++----
> arch/riscv/lib/uaccess.S | 12 ++---
> arch/riscv/mm/extable.c | 4 +-
> arch/riscv/mm/fault.c | 6 +--
> drivers/clocksource/timer-riscv.c | 8 ++--
> drivers/irqchip/irq-sifive-plic.c | 11 +++--
> 21 files changed, 199 insertions(+), 135 deletions(-)
>
> diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
> index 8eebbc8860bb..86b7e8b0471c 100644
> --- a/arch/riscv/Kconfig
> +++ b/arch/riscv/Kconfig
> @@ -72,6 +72,10 @@ config ARCH_MMAP_RND_BITS_MAX
> default 24 if 64BIT # SV39 based
> default 17
>
> +# set if we run in machine mode, cleared if we run in supervisor mode
> +config RISCV_M_MODE
> + bool
> +
> config MMU
> def_bool y
>
> diff --git a/arch/riscv/include/asm/csr.h b/arch/riscv/include/asm/csr.h
> index a18923fa23c8..0ab642811028 100644
> --- a/arch/riscv/include/asm/csr.h
> +++ b/arch/riscv/include/asm/csr.h
> @@ -11,8 +11,11 @@
>
> /* Status register flags */
> #define SR_SIE _AC(0x00000002, UL) /* Supervisor Interrupt Enable */
> +#define SR_MIE _AC(0x00000008, UL) /* Machine Interrupt Enable */
> #define SR_SPIE _AC(0x00000020, UL) /* Previous Supervisor IE */
> +#define SR_MPIE _AC(0x00000080, UL) /* Previous Machine IE */
> #define SR_SPP _AC(0x00000100, UL) /* Previously Supervisor */
> +#define SR_MPP _AC(0x00001800, UL) /* Previously Machine */
> #define SR_SUM _AC(0x00040000, UL) /* Supervisor User Memory Access */
>
> #define SR_FS _AC(0x00006000, UL) /* Floating-point Status */
> @@ -44,9 +47,10 @@
> #define SATP_MODE SATP_MODE_39
> #endif
>
> -/* SCAUSE */
> -#define SCAUSE_IRQ_FLAG (_AC(1, UL) << (__riscv_xlen - 1))
> +/* Exception cause high bit - is an interrupt if set */
> +#define CAUSE_IRQ_FLAG (_AC(1, UL) << (__riscv_xlen - 1))
>
> +/* Interrupt causes (minus the high bit) */
> #define IRQ_U_SOFT 0
> #define IRQ_S_SOFT 1
> #define IRQ_M_SOFT 3
> @@ -57,6 +61,7 @@
> #define IRQ_S_EXT 9
> #define IRQ_M_EXT 11
>
> +/* Exception causes */
> #define EXC_INST_MISALIGNED 0
> #define EXC_INST_ACCESS 1
> #define EXC_BREAKPOINT 3
> @@ -67,14 +72,14 @@
> #define EXC_LOAD_PAGE_FAULT 13
> #define EXC_STORE_PAGE_FAULT 15
>
> -/* SIE (Interrupt Enable) and SIP (Interrupt Pending) flags */
> -#define SIE_SSIE (_AC(0x1, UL) << IRQ_S_SOFT)
> -#define SIE_STIE (_AC(0x1, UL) << IRQ_S_TIMER)
> -#define SIE_SEIE (_AC(0x1, UL) << IRQ_S_EXT)
> -
> +/* symbolic CSR names: */
> #define CSR_CYCLE 0xc00
> #define CSR_TIME 0xc01
> #define CSR_INSTRET 0xc02
> +#define CSR_CYCLEH 0xc80
> +#define CSR_TIMEH 0xc81
> +#define CSR_INSTRETH 0xc82
> +
> #define CSR_SSTATUS 0x100
> #define CSR_SIE 0x104
> #define CSR_STVEC 0x105
> @@ -85,9 +90,56 @@
> #define CSR_STVAL 0x143
> #define CSR_SIP 0x144
> #define CSR_SATP 0x180
> -#define CSR_CYCLEH 0xc80
> -#define CSR_TIMEH 0xc81
> -#define CSR_INSTRETH 0xc82
> +
> +#define CSR_MSTATUS 0x300
> +#define CSR_MIE 0x304
> +#define CSR_MTVEC 0x305
> +#define CSR_MSCRATCH 0x340
> +#define CSR_MEPC 0x341
> +#define CSR_MCAUSE 0x342
> +#define CSR_MTVAL 0x343
> +#define CSR_MIP 0x344
> +
> +#ifdef CONFIG_RISCV_M_MODE
> +# define CSR_STATUS CSR_MSTATUS
> +# define CSR_IE CSR_MIE
> +# define CSR_TVEC CSR_MTVEC
> +# define CSR_SCRATCH CSR_MSCRATCH
> +# define CSR_EPC CSR_MEPC
> +# define CSR_CAUSE CSR_MCAUSE
> +# define CSR_TVAL CSR_MTVAL
> +# define CSR_IP CSR_MIP
> +
> +# define SR_IE SR_MIE
> +# define SR_PIE SR_MPIE
> +# define SR_PP SR_MPP
> +
> +# define IRQ_SOFT IRQ_M_SOFT
> +# define IRQ_TIMER IRQ_M_TIMER
> +# define IRQ_EXT IRQ_M_EXT
> +#else /* CONFIG_RISCV_M_MODE */
> +# define CSR_STATUS CSR_SSTATUS
> +# define CSR_IE CSR_SIE
> +# define CSR_TVEC CSR_STVEC
> +# define CSR_SCRATCH CSR_SSCRATCH
> +# define CSR_EPC CSR_SEPC
> +# define CSR_CAUSE CSR_SCAUSE
> +# define CSR_TVAL CSR_STVAL
> +# define CSR_IP CSR_SIP
> +
> +# define SR_IE SR_SIE
> +# define SR_PIE SR_SPIE
> +# define SR_PP SR_SPP
> +
> +# define IRQ_SOFT IRQ_S_SOFT
> +# define IRQ_TIMER IRQ_S_TIMER
> +# define IRQ_EXT IRQ_S_EXT
> +#endif /* CONFIG_RISCV_M_MODE */
> +
> +/* IE/IP (Supervisor/Machine Interrupt Enable/Pending) flags */
> +#define IE_SIE (_AC(0x1, UL) << IRQ_SOFT)
> +#define IE_TIE (_AC(0x1, UL) << IRQ_TIMER)
> +#define IE_EIE (_AC(0x1, UL) << IRQ_EXT)
>
> #ifndef __ASSEMBLY__
>
> diff --git a/arch/riscv/include/asm/irqflags.h b/arch/riscv/include/asm/irqflags.h
> index e70f647ce3b7..08d4d6a5b7e9 100644
> --- a/arch/riscv/include/asm/irqflags.h
> +++ b/arch/riscv/include/asm/irqflags.h
> @@ -13,31 +13,31 @@
> /* read interrupt enabled status */
> static inline unsigned long arch_local_save_flags(void)
> {
> - return csr_read(CSR_SSTATUS);
> + return csr_read(CSR_STATUS);
> }
>
> /* unconditionally enable interrupts */
> static inline void arch_local_irq_enable(void)
> {
> - csr_set(CSR_SSTATUS, SR_SIE);
> + csr_set(CSR_STATUS, SR_IE);
> }
>
> /* unconditionally disable interrupts */
> static inline void arch_local_irq_disable(void)
> {
> - csr_clear(CSR_SSTATUS, SR_SIE);
> + csr_clear(CSR_STATUS, SR_IE);
> }
>
> /* get status and disable interrupts */
> static inline unsigned long arch_local_irq_save(void)
> {
> - return csr_read_clear(CSR_SSTATUS, SR_SIE);
> + return csr_read_clear(CSR_STATUS, SR_IE);
> }
>
> /* test flags */
> static inline int arch_irqs_disabled_flags(unsigned long flags)
> {
> - return !(flags & SR_SIE);
> + return !(flags & SR_IE);
> }
>
> /* test hardware interrupt enable bit */
> @@ -49,7 +49,7 @@ static inline int arch_irqs_disabled(void)
> /* set interrupt enabled status */
> static inline void arch_local_irq_restore(unsigned long flags)
> {
> - csr_set(CSR_SSTATUS, flags & SR_SIE);
> + csr_set(CSR_STATUS, flags & SR_IE);
> }
>
> #endif /* _ASM_RISCV_IRQFLAGS_H */
> diff --git a/arch/riscv/include/asm/processor.h b/arch/riscv/include/asm/processor.h
> index f539149d04c2..3ddb798264f1 100644
> --- a/arch/riscv/include/asm/processor.h
> +++ b/arch/riscv/include/asm/processor.h
> @@ -42,7 +42,7 @@ struct thread_struct {
> ((struct pt_regs *)(task_stack_page(tsk) + THREAD_SIZE \
> - ALIGN(sizeof(struct pt_regs), STACK_ALIGN)))
>
> -#define KSTK_EIP(tsk) (task_pt_regs(tsk)->sepc)
> +#define KSTK_EIP(tsk) (task_pt_regs(tsk)->epc)
> #define KSTK_ESP(tsk) (task_pt_regs(tsk)->sp)
>
>
> diff --git a/arch/riscv/include/asm/ptrace.h b/arch/riscv/include/asm/ptrace.h
> index d48d1e13973c..ee49f80c9533 100644
> --- a/arch/riscv/include/asm/ptrace.h
> +++ b/arch/riscv/include/asm/ptrace.h
> @@ -12,7 +12,7 @@
> #ifndef __ASSEMBLY__
>
> struct pt_regs {
> - unsigned long sepc;
> + unsigned long epc;
> unsigned long ra;
> unsigned long sp;
> unsigned long gp;
> @@ -44,10 +44,10 @@ struct pt_regs {
> unsigned long t4;
> unsigned long t5;
> unsigned long t6;
> - /* Supervisor CSRs */
> - unsigned long sstatus;
> - unsigned long sbadaddr;
> - unsigned long scause;
> + /* Supervisor/Machine CSRs */
> + unsigned long status;
> + unsigned long badaddr;
> + unsigned long cause;
> /* a0 value before the syscall */
> unsigned long orig_a0;
> };
> @@ -58,18 +58,18 @@ struct pt_regs {
> #define REG_FMT "%08lx"
> #endif
>
> -#define user_mode(regs) (((regs)->sstatus & SR_SPP) == 0)
> +#define user_mode(regs) (((regs)->status & SR_PP) == 0)
>
>
> /* Helpers for working with the instruction pointer */
> static inline unsigned long instruction_pointer(struct pt_regs *regs)
> {
> - return regs->sepc;
> + return regs->epc;
> }
> static inline void instruction_pointer_set(struct pt_regs *regs,
> unsigned long val)
> {
> - regs->sepc = val;
> + regs->epc = val;
> }
>
> #define profile_pc(regs) instruction_pointer(regs)
> diff --git a/arch/riscv/include/asm/switch_to.h b/arch/riscv/include/asm/switch_to.h
> index f0227bdce0f0..8b5c5c8c36fa 100644
> --- a/arch/riscv/include/asm/switch_to.h
> +++ b/arch/riscv/include/asm/switch_to.h
> @@ -16,19 +16,19 @@ extern void __fstate_restore(struct task_struct *restore_from);
>
> static inline void __fstate_clean(struct pt_regs *regs)
> {
> - regs->sstatus = (regs->sstatus & ~SR_FS) | SR_FS_CLEAN;
> + regs->status = (regs->status & ~SR_FS) | SR_FS_CLEAN;
> }
>
> static inline void fstate_off(struct task_struct *task,
> struct pt_regs *regs)
> {
> - regs->sstatus = (regs->sstatus & ~SR_FS) | SR_FS_OFF;
> + regs->status = (regs->status & ~SR_FS) | SR_FS_OFF;
> }
>
> static inline void fstate_save(struct task_struct *task,
> struct pt_regs *regs)
> {
> - if ((regs->sstatus & SR_FS) == SR_FS_DIRTY) {
> + if ((regs->status & SR_FS) == SR_FS_DIRTY) {
> __fstate_save(task);
> __fstate_clean(regs);
> }
> @@ -37,7 +37,7 @@ static inline void fstate_save(struct task_struct *task,
> static inline void fstate_restore(struct task_struct *task,
> struct pt_regs *regs)
> {
> - if ((regs->sstatus & SR_FS) != SR_FS_OFF) {
> + if ((regs->status & SR_FS) != SR_FS_OFF) {
> __fstate_restore(task);
> __fstate_clean(regs);
> }
> @@ -49,7 +49,7 @@ static inline void __switch_to_aux(struct task_struct *prev,
> struct pt_regs *regs;
>
> regs = task_pt_regs(prev);
> - if (unlikely(regs->sstatus & SR_SD))
> + if (unlikely(regs->status & SR_SD))
> fstate_save(prev, regs);
> fstate_restore(next, task_pt_regs(next));
> }
> diff --git a/arch/riscv/kernel/asm-offsets.c b/arch/riscv/kernel/asm-offsets.c
> index 9f5628c38ac9..07cb9c10de4e 100644
> --- a/arch/riscv/kernel/asm-offsets.c
> +++ b/arch/riscv/kernel/asm-offsets.c
> @@ -71,7 +71,7 @@ void asm_offsets(void)
> OFFSET(TASK_THREAD_FCSR, task_struct, thread.fstate.fcsr);
>
> DEFINE(PT_SIZE, sizeof(struct pt_regs));
> - OFFSET(PT_SEPC, pt_regs, sepc);
> + OFFSET(PT_EPC, pt_regs, epc);
> OFFSET(PT_RA, pt_regs, ra);
> OFFSET(PT_FP, pt_regs, s0);
> OFFSET(PT_S0, pt_regs, s0);
> @@ -105,9 +105,9 @@ void asm_offsets(void)
> OFFSET(PT_T6, pt_regs, t6);
> OFFSET(PT_GP, pt_regs, gp);
> OFFSET(PT_ORIG_A0, pt_regs, orig_a0);
> - OFFSET(PT_SSTATUS, pt_regs, sstatus);
> - OFFSET(PT_SBADADDR, pt_regs, sbadaddr);
> - OFFSET(PT_SCAUSE, pt_regs, scause);
> + OFFSET(PT_STATUS, pt_regs, status);
> + OFFSET(PT_BADADDR, pt_regs, badaddr);
> + OFFSET(PT_CAUSE, pt_regs, cause);
>
> /*
> * THREAD_{F,X}* might be larger than a S-type offset can handle, but
> diff --git a/arch/riscv/kernel/entry.S b/arch/riscv/kernel/entry.S
> index 8ca479831142..b84f8d7f4911 100644
> --- a/arch/riscv/kernel/entry.S
> +++ b/arch/riscv/kernel/entry.S
> @@ -26,14 +26,14 @@
>
> /*
> * If coming from userspace, preserve the user thread pointer and load
> - * the kernel thread pointer. If we came from the kernel, sscratch
> - * will contain 0, and we should continue on the current TP.
> + * the kernel thread pointer. If we came from the kernel, the scratch
> + * register will contain 0, and we should continue on the current TP.
> */
> - csrrw tp, CSR_SSCRATCH, tp
> + csrrw tp, CSR_SCRATCH, tp
> bnez tp, _save_context
>
> _restore_kernel_tpsp:
> - csrr tp, CSR_SSCRATCH
> + csrr tp, CSR_SCRATCH
> REG_S sp, TASK_TI_KERNEL_SP(tp)
> _save_context:
> REG_S sp, TASK_TI_USER_SP(tp)
> @@ -79,16 +79,16 @@ _save_context:
> li t0, SR_SUM | SR_FS
>
> REG_L s0, TASK_TI_USER_SP(tp)
> - csrrc s1, CSR_SSTATUS, t0
> - csrr s2, CSR_SEPC
> - csrr s3, CSR_STVAL
> - csrr s4, CSR_SCAUSE
> - csrr s5, CSR_SSCRATCH
> + csrrc s1, CSR_STATUS, t0
> + csrr s2, CSR_EPC
> + csrr s3, CSR_TVAL
> + csrr s4, CSR_CAUSE
> + csrr s5, CSR_SCRATCH
> REG_S s0, PT_SP(sp)
> - REG_S s1, PT_SSTATUS(sp)
> - REG_S s2, PT_SEPC(sp)
> - REG_S s3, PT_SBADADDR(sp)
> - REG_S s4, PT_SCAUSE(sp)
> + REG_S s1, PT_STATUS(sp)
> + REG_S s2, PT_EPC(sp)
> + REG_S s3, PT_BADADDR(sp)
> + REG_S s4, PT_CAUSE(sp)
> REG_S s5, PT_TP(sp)
> .endm
>
> @@ -97,7 +97,7 @@ _save_context:
> * registers from the stack.
> */
> .macro RESTORE_ALL
> - REG_L a0, PT_SSTATUS(sp)
> + REG_L a0, PT_STATUS(sp)
> /*
> * The current load reservation is effectively part of the processor's
> * state, in the sense that load reservations cannot be shared between
> @@ -115,11 +115,11 @@ _save_context:
> * completes, implementations are allowed to expand reservations to be
> * arbitrarily large.
> */
> - REG_L a2, PT_SEPC(sp)
> - REG_SC x0, a2, PT_SEPC(sp)
> + REG_L a2, PT_EPC(sp)
> + REG_SC x0, a2, PT_EPC(sp)
>
> - csrw CSR_SSTATUS, a0
> - csrw CSR_SEPC, a2
> + csrw CSR_STATUS, a0
> + csrw CSR_EPC, a2
>
> REG_L x1, PT_RA(sp)
> REG_L x3, PT_GP(sp)
> @@ -163,10 +163,10 @@ ENTRY(handle_exception)
> SAVE_ALL
>
> /*
> - * Set sscratch register to 0, so that if a recursive exception
> + * Set the scratch register to 0, so that if a recursive exception
> * occurs, the exception vector knows it came from the kernel
> */
> - csrw CSR_SSCRATCH, x0
> + csrw CSR_SCRATCH, x0
>
> /* Load the global pointer */
> .option push
> @@ -185,11 +185,13 @@ ENTRY(handle_exception)
> move a0, sp /* pt_regs */
> tail do_IRQ
> 1:
> - /* Exceptions run with interrupts enabled or disabled
> - depending on the state of sstatus.SR_SPIE */
> - andi t0, s1, SR_SPIE
> + /*
> + * Exceptions run with interrupts enabled or disabled depending on the
> + * state of SR_PIE in m/sstatus.
> + */
> + andi t0, s1, SR_PIE
> beqz t0, 1f
> - csrs CSR_SSTATUS, SR_SIE
> + csrs CSR_STATUS, SR_IE
>
> 1:
> /* Handle syscalls */
> @@ -217,7 +219,7 @@ handle_syscall:
> * scall instruction on sret
> */
> addi s2, s2, 0x4
> - REG_S s2, PT_SEPC(sp)
> + REG_S s2, PT_EPC(sp)
> /* Trace syscalls, but only if requested by the user. */
> REG_L t0, TASK_TI_FLAGS(tp)
> andi t0, t0, _TIF_SYSCALL_WORK
> @@ -244,9 +246,15 @@ ret_from_syscall:
> bnez t0, handle_syscall_trace_exit
>
> ret_from_exception:
> - REG_L s0, PT_SSTATUS(sp)
> - csrc CSR_SSTATUS, SR_SIE
> + REG_L s0, PT_STATUS(sp)
> + csrc CSR_STATUS, SR_IE
> +#ifdef CONFIG_RISCV_M_MODE
> + /* the MPP value is too large to be used as an immediate arg for addi */
> + li t0, SR_MPP
> + and s0, s0, t0
> +#else
> andi s0, s0, SR_SPP
> +#endif
> bnez s0, resume_kernel
>
> resume_userspace:
> @@ -260,14 +268,18 @@ resume_userspace:
> REG_S s0, TASK_TI_KERNEL_SP(tp)
>
> /*
> - * Save TP into sscratch, so we can find the kernel data structures
> - * again.
> + * Save TP into the scratch register , so we can find the kernel data
> + * structures again.
> */
> - csrw CSR_SSCRATCH, tp
> + csrw CSR_SCRATCH, tp
>
> restore_all:
> RESTORE_ALL
> +#ifdef CONFIG_RISCV_M_MODE
> + mret
> +#else
> sret
> +#endif
>
> #if IS_ENABLED(CONFIG_PREEMPT)
> resume_kernel:
> @@ -287,7 +299,7 @@ work_pending:
> bnez s1, work_resched
> work_notifysig:
> /* Handle pending signals and notify-resume requests */
> - csrs CSR_SSTATUS, SR_SIE /* Enable interrupts for do_notify_resume() */
> + csrs CSR_STATUS, SR_IE /* Enable interrupts for do_notify_resume() */
> move a0, sp /* pt_regs */
> move a1, s0 /* current_thread_info->flags */
> tail do_notify_resume
> diff --git a/arch/riscv/kernel/fpu.S b/arch/riscv/kernel/fpu.S
> index 631d31540660..dd2205473de7 100644
> --- a/arch/riscv/kernel/fpu.S
> +++ b/arch/riscv/kernel/fpu.S
> @@ -23,7 +23,7 @@ ENTRY(__fstate_save)
> li a2, TASK_THREAD_F0
> add a0, a0, a2
> li t1, SR_FS
> - csrs CSR_SSTATUS, t1
> + csrs CSR_STATUS, t1
> frcsr t0
> fsd f0, TASK_THREAD_F0_F0(a0)
> fsd f1, TASK_THREAD_F1_F0(a0)
> @@ -58,7 +58,7 @@ ENTRY(__fstate_save)
> fsd f30, TASK_THREAD_F30_F0(a0)
> fsd f31, TASK_THREAD_F31_F0(a0)
> sw t0, TASK_THREAD_FCSR_F0(a0)
> - csrc CSR_SSTATUS, t1
> + csrc CSR_STATUS, t1
> ret
> ENDPROC(__fstate_save)
>
> @@ -67,7 +67,7 @@ ENTRY(__fstate_restore)
> add a0, a0, a2
> li t1, SR_FS
> lw t0, TASK_THREAD_FCSR_F0(a0)
> - csrs CSR_SSTATUS, t1
> + csrs CSR_STATUS, t1
> fld f0, TASK_THREAD_F0_F0(a0)
> fld f1, TASK_THREAD_F1_F0(a0)
> fld f2, TASK_THREAD_F2_F0(a0)
> @@ -101,6 +101,6 @@ ENTRY(__fstate_restore)
> fld f30, TASK_THREAD_F30_F0(a0)
> fld f31, TASK_THREAD_F31_F0(a0)
> fscsr t0
> - csrc CSR_SSTATUS, t1
> + csrc CSR_STATUS, t1
> ret
> ENDPROC(__fstate_restore)
> diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
> index 72f89b7590dd..5cfd2c582945 100644
> --- a/arch/riscv/kernel/head.S
> +++ b/arch/riscv/kernel/head.S
> @@ -47,8 +47,8 @@ ENTRY(_start)
> .global _start_kernel
> _start_kernel:
> /* Mask all interrupts */
> - csrw CSR_SIE, zero
> - csrw CSR_SIP, zero
> + csrw CSR_IE, zero
> + csrw CSR_IP, zero
>
> /* Load the global pointer */
> .option push
> @@ -61,7 +61,7 @@ _start_kernel:
> * floating point in kernel space
> */
> li t0, SR_FS
> - csrc CSR_SSTATUS, t0
> + csrc CSR_STATUS, t0
>
> #ifdef CONFIG_SMP
> li t0, CONFIG_NR_CPUS
> @@ -116,7 +116,7 @@ relocate:
> /* Point stvec to virtual address of intruction after satp write */
> la a2, 1f
> add a2, a2, a1
> - csrw CSR_STVEC, a2
> + csrw CSR_TVEC, a2
>
> /* Compute satp for kernel page tables, but don't load it yet */
> srl a2, a0, PAGE_SHIFT
> @@ -138,7 +138,7 @@ relocate:
> 1:
> /* Set trap vector to spin forever to help debug */
> la a0, .Lsecondary_park
> - csrw CSR_STVEC, a0
> + csrw CSR_TVEC, a0
>
> /* Reload the global pointer */
> .option push
> @@ -161,7 +161,7 @@ relocate:
> #ifdef CONFIG_SMP
> /* Set trap vector to spin forever to help debug */
> la a3, .Lsecondary_park
> - csrw CSR_STVEC, a3
> + csrw CSR_TVEC, a3
>
> slli a3, a0, LGREG
> la a1, __cpu_up_stack_pointer
> diff --git a/arch/riscv/kernel/irq.c b/arch/riscv/kernel/irq.c
> index 6d8659388c49..7446b96f8575 100644
> --- a/arch/riscv/kernel/irq.c
> +++ b/arch/riscv/kernel/irq.c
> @@ -11,13 +11,6 @@
> #include <linux/seq_file.h>
> #include <asm/smp.h>
>
> -/*
> - * Possible interrupt causes:
> - */
> -#define INTERRUPT_CAUSE_SOFTWARE IRQ_S_SOFT
> -#define INTERRUPT_CAUSE_TIMER IRQ_S_TIMER
> -#define INTERRUPT_CAUSE_EXTERNAL IRQ_S_EXT
> -
> int arch_show_interrupts(struct seq_file *p, int prec)
> {
> show_ipi_stats(p, prec);
> @@ -29,12 +22,12 @@ asmlinkage void __irq_entry do_IRQ(struct pt_regs *regs)
> struct pt_regs *old_regs = set_irq_regs(regs);
>
> irq_enter();
> - switch (regs->scause & ~SCAUSE_IRQ_FLAG) {
> - case INTERRUPT_CAUSE_TIMER:
> + switch (regs->cause & ~CAUSE_IRQ_FLAG) {
> + case IRQ_TIMER:
> riscv_timer_interrupt();
> break;
> #ifdef CONFIG_SMP
> - case INTERRUPT_CAUSE_SOFTWARE:
> + case IRQ_SOFT:
> /*
> * We only use software interrupts to pass IPIs, so if a non-SMP
> * system gets one, then we don't know what to do.
> @@ -42,11 +35,11 @@ asmlinkage void __irq_entry do_IRQ(struct pt_regs *regs)
> riscv_software_interrupt();
> break;
> #endif
> - case INTERRUPT_CAUSE_EXTERNAL:
> + case IRQ_EXT:
> handle_arch_irq(regs);
> break;
> default:
> - pr_alert("unexpected interrupt cause 0x%lx", regs->scause);
> + pr_alert("unexpected interrupt cause 0x%lx", regs->cause);
> BUG();
> }
> irq_exit();
> diff --git a/arch/riscv/kernel/perf_callchain.c b/arch/riscv/kernel/perf_callchain.c
> index 8d2804f05cf9..cf190197a22f 100644
> --- a/arch/riscv/kernel/perf_callchain.c
> +++ b/arch/riscv/kernel/perf_callchain.c
> @@ -67,7 +67,7 @@ void perf_callchain_user(struct perf_callchain_entry_ctx *entry,
> return;
>
> fp = regs->s0;
> - perf_callchain_store(entry, regs->sepc);
> + perf_callchain_store(entry, regs->epc);
>
> fp = user_backtrace(entry, fp, regs->ra);
> while (fp && !(fp & 0x3) && entry->nr < entry->max_stack)
> diff --git a/arch/riscv/kernel/process.c b/arch/riscv/kernel/process.c
> index fb3a082362eb..d8149d8c0207 100644
> --- a/arch/riscv/kernel/process.c
> +++ b/arch/riscv/kernel/process.c
> @@ -33,8 +33,8 @@ void show_regs(struct pt_regs *regs)
> {
> show_regs_print_info(KERN_DEFAULT);
>
> - pr_cont("sepc: " REG_FMT " ra : " REG_FMT " sp : " REG_FMT "\n",
> - regs->sepc, regs->ra, regs->sp);
> + pr_cont("epc: " REG_FMT " ra : " REG_FMT " sp : " REG_FMT "\n",
> + regs->epc, regs->ra, regs->sp);
> pr_cont(" gp : " REG_FMT " tp : " REG_FMT " t0 : " REG_FMT "\n",
> regs->gp, regs->tp, regs->t0);
> pr_cont(" t1 : " REG_FMT " t2 : " REG_FMT " s0 : " REG_FMT "\n",
> @@ -56,23 +56,23 @@ void show_regs(struct pt_regs *regs)
> pr_cont(" t5 : " REG_FMT " t6 : " REG_FMT "\n",
> regs->t5, regs->t6);
>
> - pr_cont("sstatus: " REG_FMT " sbadaddr: " REG_FMT " scause: " REG_FMT "\n",
> - regs->sstatus, regs->sbadaddr, regs->scause);
> + pr_cont("status: " REG_FMT " badaddr: " REG_FMT " cause: " REG_FMT "\n",
> + regs->status, regs->badaddr, regs->cause);
> }
>
> void start_thread(struct pt_regs *regs, unsigned long pc,
> unsigned long sp)
> {
> - regs->sstatus = SR_SPIE;
> + regs->status = SR_PIE;
> if (has_fpu) {
> - regs->sstatus |= SR_FS_INITIAL;
> + regs->status |= SR_FS_INITIAL;
> /*
> * Restore the initial value to the FP register
> * before starting the user program.
> */
> fstate_restore(current, regs);
> }
> - regs->sepc = pc;
> + regs->epc = pc;
> regs->sp = sp;
> set_fs(USER_DS);
> }
> @@ -108,7 +108,8 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
> const register unsigned long gp __asm__ ("gp");
> memset(childregs, 0, sizeof(struct pt_regs));
> childregs->gp = gp;
> - childregs->sstatus = SR_SPP | SR_SPIE; /* Supervisor, irqs on */
> + /* Supervisor/Machine, irqs on: */
> + childregs->status = SR_PP | SR_PIE;
>
> p->thread.ra = (unsigned long)ret_from_kernel_thread;
> p->thread.s[0] = usp; /* fn */
> diff --git a/arch/riscv/kernel/signal.c b/arch/riscv/kernel/signal.c
> index b14d7647d800..c639d517bc03 100644
> --- a/arch/riscv/kernel/signal.c
> +++ b/arch/riscv/kernel/signal.c
> @@ -124,7 +124,7 @@ SYSCALL_DEFINE0(rt_sigreturn)
> pr_info_ratelimited(
> "%s[%d]: bad frame in %s: frame=%p pc=%p sp=%p\n",
> task->comm, task_pid_nr(task), __func__,
> - frame, (void *)regs->sepc, (void *)regs->sp);
> + frame, (void *)regs->epc, (void *)regs->sp);
> }
> force_sig(SIGSEGV);
> return 0;
> @@ -199,7 +199,7 @@ static int setup_rt_frame(struct ksignal *ksig, sigset_t *set,
> * We always pass siginfo and mcontext, regardless of SA_SIGINFO,
> * since some things rely on this (e.g. glibc's debug/segfault.c).
> */
> - regs->sepc = (unsigned long)ksig->ka.sa.sa_handler;
> + regs->epc = (unsigned long)ksig->ka.sa.sa_handler;
> regs->sp = (unsigned long)frame;
> regs->a0 = ksig->sig; /* a0: signal number */
> regs->a1 = (unsigned long)(&frame->info); /* a1: siginfo pointer */
> @@ -208,7 +208,7 @@ static int setup_rt_frame(struct ksignal *ksig, sigset_t *set,
> #if DEBUG_SIG
> pr_info("SIG deliver (%s:%d): sig=%d pc=%p ra=%p sp=%p\n",
> current->comm, task_pid_nr(current), ksig->sig,
> - (void *)regs->sepc, (void *)regs->ra, frame);
> + (void *)regs->epc, (void *)regs->ra, frame);
> #endif
>
> return 0;
> @@ -220,10 +220,9 @@ static void handle_signal(struct ksignal *ksig, struct pt_regs *regs)
> int ret;
>
> /* Are we from a system call? */
> - if (regs->scause == EXC_SYSCALL) {
> + if (regs->cause == EXC_SYSCALL) {
> /* Avoid additional syscall restarting via ret_from_exception */
> - regs->scause = -1UL;
> -
> + regs->cause = -1UL;
> /* If so, check system call restarting.. */
> switch (regs->a0) {
> case -ERESTART_RESTARTBLOCK:
> @@ -239,7 +238,7 @@ static void handle_signal(struct ksignal *ksig, struct pt_regs *regs)
> /* fallthrough */
> case -ERESTARTNOINTR:
> regs->a0 = regs->orig_a0;
> - regs->sepc -= 0x4;
> + regs->epc -= 0x4;
> break;
> }
> }
> @@ -261,9 +260,9 @@ static void do_signal(struct pt_regs *regs)
> }
>
> /* Did we come from a system call? */
> - if (regs->scause == EXC_SYSCALL) {
> + if (regs->cause == EXC_SYSCALL) {
> /* Avoid additional syscall restarting via ret_from_exception */
> - regs->scause = -1UL;
> + regs->cause = -1UL;
>
> /* Restart the system call - no handlers present */
> switch (regs->a0) {
> @@ -271,12 +270,12 @@ static void do_signal(struct pt_regs *regs)
> case -ERESTARTSYS:
> case -ERESTARTNOINTR:
> regs->a0 = regs->orig_a0;
> - regs->sepc -= 0x4;
> + regs->epc -= 0x4;
> break;
> case -ERESTART_RESTARTBLOCK:
> regs->a0 = regs->orig_a0;
> regs->a7 = __NR_restart_syscall;
> - regs->sepc -= 0x4;
> + regs->epc -= 0x4;
> break;
> }
> }
> diff --git a/arch/riscv/kernel/smp.c b/arch/riscv/kernel/smp.c
> index b18cd6c8e8fb..51627c3aa4b8 100644
> --- a/arch/riscv/kernel/smp.c
> +++ b/arch/riscv/kernel/smp.c
> @@ -106,7 +106,7 @@ static void send_ipi_single(int cpu, enum ipi_message_type op)
>
> static inline void clear_ipi(void)
> {
> - csr_clear(CSR_SIP, SIE_SSIE);
> + csr_clear(CSR_IP, IE_SIE);
> }
>
> void riscv_software_interrupt(void)
> diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c
> index 10a17e545f43..f218cf0c4f60 100644
> --- a/arch/riscv/kernel/traps.c
> +++ b/arch/riscv/kernel/traps.c
> @@ -40,7 +40,7 @@ void die(struct pt_regs *regs, const char *str)
> print_modules();
> show_regs(regs);
>
> - ret = notify_die(DIE_OOPS, str, regs, 0, regs->scause, SIGSEGV);
> + ret = notify_die(DIE_OOPS, str, regs, 0, regs->cause, SIGSEGV);
>
> bust_spinlocks(0);
> add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
> @@ -85,7 +85,7 @@ static void do_trap_error(struct pt_regs *regs, int signo, int code,
> #define DO_ERROR_INFO(name, signo, code, str) \
> asmlinkage void name(struct pt_regs *regs) \
> { \
> - do_trap_error(regs, signo, code, regs->sepc, "Oops - " str); \
> + do_trap_error(regs, signo, code, regs->epc, "Oops - " str); \
> }
>
> DO_ERROR_INFO(do_trap_unknown,
> @@ -123,9 +123,9 @@ static inline unsigned long get_break_insn_length(unsigned long pc)
> asmlinkage void do_trap_break(struct pt_regs *regs)
> {
> if (user_mode(regs))
> - force_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *)regs->sepc);
> - else if (report_bug(regs->sepc, regs) == BUG_TRAP_TYPE_WARN)
> - regs->sepc += get_break_insn_length(regs->sepc);
> + force_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *)regs->epc);
> + else if (report_bug(regs->epc, regs) == BUG_TRAP_TYPE_WARN)
> + regs->epc += get_break_insn_length(regs->epc);
> else
> die(regs, "Kernel BUG");
> }
> @@ -152,9 +152,9 @@ void __init trap_init(void)
> * Set sup0 scratch register to 0, indicating to exception vector
> * that we are presently executing in the kernel
> */
> - csr_write(CSR_SSCRATCH, 0);
> + csr_write(CSR_SCRATCH, 0);
> /* Set the exception vector address */
> - csr_write(CSR_STVEC, &handle_exception);
> + csr_write(CSR_TVEC, &handle_exception);
> /* Enable all interrupts */
> - csr_write(CSR_SIE, -1);
> + csr_write(CSR_IE, -1);
> }
> diff --git a/arch/riscv/lib/uaccess.S b/arch/riscv/lib/uaccess.S
> index ed2696c0143d..fecd65657a6f 100644
> --- a/arch/riscv/lib/uaccess.S
> +++ b/arch/riscv/lib/uaccess.S
> @@ -18,7 +18,7 @@ ENTRY(__asm_copy_from_user)
>
> /* Enable access to user memory */
> li t6, SR_SUM
> - csrs CSR_SSTATUS, t6
> + csrs CSR_STATUS, t6
>
> add a3, a1, a2
> /* Use word-oriented copy only if low-order bits match */
> @@ -47,7 +47,7 @@ ENTRY(__asm_copy_from_user)
>
> 3:
> /* Disable access to user memory */
> - csrc CSR_SSTATUS, t6
> + csrc CSR_STATUS, t6
> li a0, 0
> ret
> 4: /* Edge case: unalignment */
> @@ -72,7 +72,7 @@ ENTRY(__clear_user)
>
> /* Enable access to user memory */
> li t6, SR_SUM
> - csrs CSR_SSTATUS, t6
> + csrs CSR_STATUS, t6
>
> add a3, a0, a1
> addi t0, a0, SZREG-1
> @@ -94,7 +94,7 @@ ENTRY(__clear_user)
>
> 3:
> /* Disable access to user memory */
> - csrc CSR_SSTATUS, t6
> + csrc CSR_STATUS, t6
> li a0, 0
> ret
> 4: /* Edge case: unalignment */
> @@ -114,11 +114,11 @@ ENDPROC(__clear_user)
> /* Fixup code for __copy_user(10) and __clear_user(11) */
> 10:
> /* Disable access to user memory */
> - csrs CSR_SSTATUS, t6
> + csrs CSR_STATUS, t6
> mv a0, a2
> ret
> 11:
> - csrs CSR_SSTATUS, t6
> + csrs CSR_STATUS, t6
> mv a0, a1
> ret
> .previous
> diff --git a/arch/riscv/mm/extable.c b/arch/riscv/mm/extable.c
> index 7aed9178d365..2fc729422151 100644
> --- a/arch/riscv/mm/extable.c
> +++ b/arch/riscv/mm/extable.c
> @@ -15,9 +15,9 @@ int fixup_exception(struct pt_regs *regs)
> {
> const struct exception_table_entry *fixup;
>
> - fixup = search_exception_tables(regs->sepc);
> + fixup = search_exception_tables(regs->epc);
> if (fixup) {
> - regs->sepc = fixup->fixup;
> + regs->epc = fixup->fixup;
> return 1;
> }
> return 0;
> diff --git a/arch/riscv/mm/fault.c b/arch/riscv/mm/fault.c
> index 96add1427a75..081fab3fbda9 100644
> --- a/arch/riscv/mm/fault.c
> +++ b/arch/riscv/mm/fault.c
> @@ -32,8 +32,8 @@ asmlinkage void do_page_fault(struct pt_regs *regs)
> int code = SEGV_MAPERR;
> vm_fault_t fault;
>
> - cause = regs->scause;
> - addr = regs->sbadaddr;
> + cause = regs->cause;
> + addr = regs->badaddr;
>
> tsk = current;
> mm = tsk->mm;
> @@ -51,7 +51,7 @@ asmlinkage void do_page_fault(struct pt_regs *regs)
> goto vmalloc_fault;
>
> /* Enable interrupts if they were enabled in the parent context. */
> - if (likely(regs->sstatus & SR_SPIE))
> + if (likely(regs->status & SR_PIE))
> local_irq_enable();
>
> /*
> diff --git a/drivers/clocksource/timer-riscv.c b/drivers/clocksource/timer-riscv.c
> index 470c7ef02ea4..d083bfb535f6 100644
> --- a/drivers/clocksource/timer-riscv.c
> +++ b/drivers/clocksource/timer-riscv.c
> @@ -19,7 +19,7 @@
> static int riscv_clock_next_event(unsigned long delta,
> struct clock_event_device *ce)
> {
> - csr_set(sie, SIE_STIE);
> + csr_set(CSR_IE, IE_TIE);
> sbi_set_timer(get_cycles64() + delta);
> return 0;
> }
> @@ -61,13 +61,13 @@ static int riscv_timer_starting_cpu(unsigned int cpu)
> ce->cpumask = cpumask_of(cpu);
> clockevents_config_and_register(ce, riscv_timebase, 100, 0x7fffffff);
>
> - csr_set(sie, SIE_STIE);
> + csr_set(CSR_IE, IE_TIE);
> return 0;
> }
>
> static int riscv_timer_dying_cpu(unsigned int cpu)
> {
> - csr_clear(sie, SIE_STIE);
> + csr_clear(CSR_IE, IE_TIE);
> return 0;
> }
>
> @@ -76,7 +76,7 @@ void riscv_timer_interrupt(void)
> {
> struct clock_event_device *evdev = this_cpu_ptr(&riscv_clock_event);
>
> - csr_clear(sie, SIE_STIE);
> + csr_clear(CSR_IE, IE_TIE);
> evdev->event_handler(evdev);
> }
>
> diff --git a/drivers/irqchip/irq-sifive-plic.c b/drivers/irqchip/irq-sifive-plic.c
> index 7d0a12fe2714..8df547d2d935 100644
> --- a/drivers/irqchip/irq-sifive-plic.c
> +++ b/drivers/irqchip/irq-sifive-plic.c
> @@ -181,7 +181,7 @@ static void plic_handle_irq(struct pt_regs *regs)
>
> WARN_ON_ONCE(!handler->present);
>
> - csr_clear(sie, SIE_SEIE);
> + csr_clear(CSR_IE, IE_EIE);
> while ((hwirq = readl(claim))) {
> int irq = irq_find_mapping(plic_irqdomain, hwirq);
>
> @@ -191,7 +191,7 @@ static void plic_handle_irq(struct pt_regs *regs)
> else
> generic_handle_irq(irq);
> }
> - csr_set(sie, SIE_SEIE);
> + csr_set(CSR_IE, IE_EIE);
> }
>
> /*
> @@ -252,8 +252,11 @@ static int __init plic_init(struct device_node *node,
> continue;
> }
>
> - /* skip contexts other than supervisor external interrupt */
> - if (parent.args[0] != IRQ_S_EXT)
> + /*
> + * Skip contexts other than external interrupts for our
> + * privilege level.
> + */
> + if (parent.args[0] != IRQ_EXT)
> continue;
>
> hartid = plic_find_hart_id(parent.np);
> --
> 2.20.1
>
>

- Paul