Re: [PATCH v1 08/14] xen/riscv: introduce decode_cause() stuff

[Alistair Francis <alistair23@xxxxxxxxx>]

On Sat, Jan 21, 2023 at 1:00 AM Oleksii Kurochko
<oleksii.kurochko@xxxxxxxxx> wrote:
>
> The patch introduces stuff needed to decode a reason of an
> exception.
>
> Signed-off-by: Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx>

Reviewed-by: Alistair Francis <alistair.francis@xxxxxxx>

Alistair

> ---
>  xen/arch/riscv/traps.c | 88 ++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 88 insertions(+)
>
> diff --git a/xen/arch/riscv/traps.c b/xen/arch/riscv/traps.c
> index 3201b851ef..dd64f053a5 100644
> --- a/xen/arch/riscv/traps.c
> +++ b/xen/arch/riscv/traps.c
> @@ -4,8 +4,96 @@
>   *
>   * RISC-V Trap handlers
>   */
> +#include <asm/csr.h>
> +#include <asm/early_printk.h>
>  #include <asm/processor.h>
>  #include <asm/traps.h>
> +#include <xen/errno.h>
> +
> +const char *decode_trap_cause(unsigned long cause)
> +{
> +    switch ( cause )
> +    {
> +    case CAUSE_MISALIGNED_FETCH:
> +        return "Instruction Address Misaligned";
> +    case CAUSE_FETCH_ACCESS:
> +        return "Instruction Access Fault";
> +    case CAUSE_ILLEGAL_INSTRUCTION:
> +        return "Illegal Instruction";
> +    case CAUSE_BREAKPOINT:
> +        return "Breakpoint";
> +    case CAUSE_MISALIGNED_LOAD:
> +        return "Load Address Misaligned";
> +    case CAUSE_LOAD_ACCESS:
> +        return "Load Access Fault";
> +    case CAUSE_MISALIGNED_STORE:
> +        return "Store/AMO Address Misaligned";
> +    case CAUSE_STORE_ACCESS:
> +        return "Store/AMO Access Fault";
> +    case CAUSE_USER_ECALL:
> +        return "Environment Call from U-Mode";
> +    case CAUSE_SUPERVISOR_ECALL:
> +        return "Environment Call from S-Mode";
> +    case CAUSE_MACHINE_ECALL:
> +        return "Environment Call from M-Mode";
> +    case CAUSE_FETCH_PAGE_FAULT:
> +        return "Instruction Page Fault";
> +    case CAUSE_LOAD_PAGE_FAULT:
> +        return "Load Page Fault";
> +    case CAUSE_STORE_PAGE_FAULT:
> +        return "Store/AMO Page Fault";
> +    case CAUSE_FETCH_GUEST_PAGE_FAULT:
> +        return "Instruction Guest Page Fault";
> +    case CAUSE_LOAD_GUEST_PAGE_FAULT:
> +        return "Load Guest Page Fault";
> +    case CAUSE_VIRTUAL_INST_FAULT:
> +        return "Virtualized Instruction Fault";
> +    case CAUSE_STORE_GUEST_PAGE_FAULT:
> +        return "Guest Store/AMO Page Fault";
> +    default:
> +        return "UNKNOWN";
> +    }
> +}
> +
> +const char *decode_reserved_interrupt_cause(unsigned long irq_cause)
> +{
> +    switch ( irq_cause )
> +    {
> +    case IRQ_M_SOFT:
> +        return "M-mode Software Interrupt";
> +    case IRQ_M_TIMER:
> +        return "M-mode TIMER Interrupt";
> +    case IRQ_M_EXT:
> +        return "M-mode TIMER Interrupt";
> +    default:
> +        return "UNKNOWN IRQ type";
> +    }
> +}
> +
> +const char *decode_interrupt_cause(unsigned long cause)
> +{
> +    unsigned long irq_cause = cause & ~CAUSE_IRQ_FLAG;
> +
> +    switch ( irq_cause )
> +    {
> +    case IRQ_S_SOFT:
> +        return "Supervisor Software Interrupt";
> +    case IRQ_S_TIMER:
> +        return "Supervisor Timer Interrupt";
> +    case IRQ_S_EXT:
> +        return "Supervisor External Interrupt";
> +    default:
> +        return decode_reserved_interrupt_cause(irq_cause);
> +    }
> +}
> +
> +const char *decode_cause(unsigned long cause)
> +{
> +    if ( cause & CAUSE_IRQ_FLAG )
> +        return decode_interrupt_cause(cause);
> +
> +    return decode_trap_cause(cause);
> +}
>
>  void __handle_exception(struct cpu_user_regs *cpu_regs)
>  {
> --
> 2.39.0
>
>