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[PATCH v3 09/14] xen/riscv: introduce decode_cause() stuff

Oleksii Kurochko posted 14 patches 3 years ago
Only 13 patches received!
There is a newer version of this series
[PATCH v3 09/14] xen/riscv: introduce decode_cause() stuff
Posted by Oleksii Kurochko 3 years ago 
The patch introduces stuff needed to decode a reason of an
exception.

Signed-off-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
---
Changes in V3:
  - Nothing changed
---
Changes in V2:
  - Make decode_trap_cause() more optimization friendly.
  - Merge the pathc which introduces do_unexpected_trap() to the current one.
---
 xen/arch/riscv/traps.c | 85 +++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 84 insertions(+), 1 deletion(-)

diff --git a/xen/arch/riscv/traps.c b/xen/arch/riscv/traps.c
index ccd3593f5a..f2a1e1ffcf 100644
--- a/xen/arch/riscv/traps.c
+++ b/xen/arch/riscv/traps.c
@@ -4,10 +4,93 @@
  *
  * 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>
+#include <xen/lib.h>
 
-void do_trap(struct cpu_user_regs *cpu_regs)
+static const char *decode_trap_cause(unsigned long cause)
+{
+    static const char *const trap_causes[] = {
+        [CAUSE_MISALIGNED_FETCH] = "Instruction Address Misaligned",
+        [CAUSE_FETCH_ACCESS] = "Instruction Access Fault",
+        [CAUSE_ILLEGAL_INSTRUCTION] = "Illegal Instruction",
+        [CAUSE_BREAKPOINT] = "Breakpoint",
+        [CAUSE_MISALIGNED_LOAD] = "Load Address Misaligned",
+        [CAUSE_LOAD_ACCESS] = "Load Access Fault",
+        [CAUSE_MISALIGNED_STORE] = "Store/AMO Address Misaligned",
+        [CAUSE_STORE_ACCESS] = "Store/AMO Access Fault",
+        [CAUSE_USER_ECALL] = "Environment Call from U-Mode",
+        [CAUSE_SUPERVISOR_ECALL] = "Environment Call from S-Mode",
+        [CAUSE_MACHINE_ECALL] = "Environment Call from M-Mode",
+        [CAUSE_FETCH_PAGE_FAULT] = "Instruction Page Fault",
+        [CAUSE_LOAD_PAGE_FAULT] = "Load Page Fault",
+        [CAUSE_STORE_PAGE_FAULT] = "Store/AMO Page Fault",
+        [CAUSE_FETCH_GUEST_PAGE_FAULT] = "Instruction Guest Page Fault",
+        [CAUSE_LOAD_GUEST_PAGE_FAULT] = "Load Guest Page Fault",
+        [CAUSE_VIRTUAL_INST_FAULT] = "Virtualized Instruction Fault",
+        [CAUSE_STORE_GUEST_PAGE_FAULT] = "Guest Store/AMO Page Fault",
+    };
+
+    if ( cause < ARRAY_SIZE(trap_causes) && trap_causes[cause] )
+        return trap_causes[cause];
+    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);
+}
+
+static void do_unexpected_trap(const struct cpu_user_regs *regs)
 {
+    unsigned long cause = csr_read(CSR_SCAUSE);
+
+    early_printk("Unhandled exception: ");
+    early_printk(decode_cause(cause));
+    early_printk("\n");
+
     die();
 }
+
+void do_trap(struct cpu_user_regs *cpu_regs)
+{
+    do_unexpected_trap(cpu_regs);
+}
-- 
2.39.0
Re: [PATCH v3 09/14] xen/riscv: introduce decode_cause() stuff
Posted by Alistair Francis 2 years, 12 months ago 
On Wed, Feb 8, 2023 at 12:48 AM Oleksii Kurochko
<oleksii.kurochko@gmail.com> wrote:
>
> The patch introduces stuff needed to decode a reason of an
> exception.
>
> Signed-off-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
> ---
> Changes in V3:
>   - Nothing changed
> ---
> Changes in V2:
>   - Make decode_trap_cause() more optimization friendly.
>   - Merge the pathc which introduces do_unexpected_trap() to the current one.
> ---
>  xen/arch/riscv/traps.c | 85 +++++++++++++++++++++++++++++++++++++++++-
>  1 file changed, 84 insertions(+), 1 deletion(-)
>
> diff --git a/xen/arch/riscv/traps.c b/xen/arch/riscv/traps.c
> index ccd3593f5a..f2a1e1ffcf 100644
> --- a/xen/arch/riscv/traps.c
> +++ b/xen/arch/riscv/traps.c
> @@ -4,10 +4,93 @@
>   *
>   * 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>
> +#include <xen/lib.h>
>
> -void do_trap(struct cpu_user_regs *cpu_regs)
> +static const char *decode_trap_cause(unsigned long cause)
> +{
> +    static const char *const trap_causes[] = {
> +        [CAUSE_MISALIGNED_FETCH] = "Instruction Address Misaligned",
> +        [CAUSE_FETCH_ACCESS] = "Instruction Access Fault",
> +        [CAUSE_ILLEGAL_INSTRUCTION] = "Illegal Instruction",
> +        [CAUSE_BREAKPOINT] = "Breakpoint",
> +        [CAUSE_MISALIGNED_LOAD] = "Load Address Misaligned",
> +        [CAUSE_LOAD_ACCESS] = "Load Access Fault",
> +        [CAUSE_MISALIGNED_STORE] = "Store/AMO Address Misaligned",
> +        [CAUSE_STORE_ACCESS] = "Store/AMO Access Fault",
> +        [CAUSE_USER_ECALL] = "Environment Call from U-Mode",
> +        [CAUSE_SUPERVISOR_ECALL] = "Environment Call from S-Mode",
> +        [CAUSE_MACHINE_ECALL] = "Environment Call from M-Mode",
> +        [CAUSE_FETCH_PAGE_FAULT] = "Instruction Page Fault",
> +        [CAUSE_LOAD_PAGE_FAULT] = "Load Page Fault",
> +        [CAUSE_STORE_PAGE_FAULT] = "Store/AMO Page Fault",
> +        [CAUSE_FETCH_GUEST_PAGE_FAULT] = "Instruction Guest Page Fault",
> +        [CAUSE_LOAD_GUEST_PAGE_FAULT] = "Load Guest Page Fault",
> +        [CAUSE_VIRTUAL_INST_FAULT] = "Virtualized Instruction Fault",
> +        [CAUSE_STORE_GUEST_PAGE_FAULT] = "Guest Store/AMO Page Fault",
> +    };
> +
> +    if ( cause < ARRAY_SIZE(trap_causes) && trap_causes[cause] )
> +        return trap_causes[cause];
> +    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";

Wrong string here

Alistair

> +    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);
> +}
> +
> +static void do_unexpected_trap(const struct cpu_user_regs *regs)
>  {
> +    unsigned long cause = csr_read(CSR_SCAUSE);
> +
> +    early_printk("Unhandled exception: ");
> +    early_printk(decode_cause(cause));
> +    early_printk("\n");
> +
>      die();
>  }
> +
> +void do_trap(struct cpu_user_regs *cpu_regs)
> +{
> +    do_unexpected_trap(cpu_regs);
> +}
> --
> 2.39.0
>
>
Re: [PATCH v3 09/14] xen/riscv: introduce decode_cause() stuff
Posted by Oleksii 2 years, 12 months ago 
On Fri, 2023-02-10 at 12:00 +1000, Alistair Francis wrote:
> On Wed, Feb 8, 2023 at 12:48 AM Oleksii Kurochko
> <oleksii.kurochko@gmail.com> wrote:
> > 
> > The patch introduces stuff needed to decode a reason of an
> > exception.
> > 
> > Signed-off-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
> > ---
> > Changes in V3:
> >   - Nothing changed
> > ---
> > Changes in V2:
> >   - Make decode_trap_cause() more optimization friendly.
> >   - Merge the pathc which introduces do_unexpected_trap() to the
> > current one.
> > ---
> >  xen/arch/riscv/traps.c | 85
> > +++++++++++++++++++++++++++++++++++++++++-
> >  1 file changed, 84 insertions(+), 1 deletion(-)
> > 
> > diff --git a/xen/arch/riscv/traps.c b/xen/arch/riscv/traps.c
> > index ccd3593f5a..f2a1e1ffcf 100644
> > --- a/xen/arch/riscv/traps.c
> > +++ b/xen/arch/riscv/traps.c
> > @@ -4,10 +4,93 @@
> >   *
> >   * 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>
> > +#include <xen/lib.h>
> > 
> > -void do_trap(struct cpu_user_regs *cpu_regs)
> > +static const char *decode_trap_cause(unsigned long cause)
> > +{
> > +    static const char *const trap_causes[] = {
> > +        [CAUSE_MISALIGNED_FETCH] = "Instruction Address
> > Misaligned",
> > +        [CAUSE_FETCH_ACCESS] = "Instruction Access Fault",
> > +        [CAUSE_ILLEGAL_INSTRUCTION] = "Illegal Instruction",
> > +        [CAUSE_BREAKPOINT] = "Breakpoint",
> > +        [CAUSE_MISALIGNED_LOAD] = "Load Address Misaligned",
> > +        [CAUSE_LOAD_ACCESS] = "Load Access Fault",
> > +        [CAUSE_MISALIGNED_STORE] = "Store/AMO Address Misaligned",
> > +        [CAUSE_STORE_ACCESS] = "Store/AMO Access Fault",
> > +        [CAUSE_USER_ECALL] = "Environment Call from U-Mode",
> > +        [CAUSE_SUPERVISOR_ECALL] = "Environment Call from S-Mode",
> > +        [CAUSE_MACHINE_ECALL] = "Environment Call from M-Mode",
> > +        [CAUSE_FETCH_PAGE_FAULT] = "Instruction Page Fault",
> > +        [CAUSE_LOAD_PAGE_FAULT] = "Load Page Fault",
> > +        [CAUSE_STORE_PAGE_FAULT] = "Store/AMO Page Fault",
> > +        [CAUSE_FETCH_GUEST_PAGE_FAULT] = "Instruction Guest Page
> > Fault",
> > +        [CAUSE_LOAD_GUEST_PAGE_FAULT] = "Load Guest Page Fault",
> > +        [CAUSE_VIRTUAL_INST_FAULT] = "Virtualized Instruction
> > Fault",
> > +        [CAUSE_STORE_GUEST_PAGE_FAULT] = "Guest Store/AMO Page
> > Fault",
> > +    };
> > +
> > +    if ( cause < ARRAY_SIZE(trap_causes) && trap_causes[cause] )
> > +        return trap_causes[cause];
> > +    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";
> 
> Wrong string here
> 
> Alistair
> 
Nice catch.
Thanks a lot.
> > +    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);
> > +}
> > +
> > +static void do_unexpected_trap(const struct cpu_user_regs *regs)
> >  {
> > +    unsigned long cause = csr_read(CSR_SCAUSE);
> > +
> > +    early_printk("Unhandled exception: ");
> > +    early_printk(decode_cause(cause));
> > +    early_printk("\n");
> > +
> >      die();
> >  }
> > +
> > +void do_trap(struct cpu_user_regs *cpu_regs)
> > +{
> > +    do_unexpected_trap(cpu_regs);
> > +}
> > --
> > 2.39.0
> > 
> >
Re: [PATCH v3 09/14] xen/riscv: introduce decode_cause() stuff
Posted by Oleksii 2 years, 12 months ago 
On Fri, 2023-02-10 at 12:00 +1000, Alistair Francis wrote:
> On Wed, Feb 8, 2023 at 12:48 AM Oleksii Kurochko
> <oleksii.kurochko@gmail.com> wrote:
> > 
> > The patch introduces stuff needed to decode a reason of an
> > exception.
> > 
> > Signed-off-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
> > ---
> > Changes in V3:
> >   - Nothing changed
> > ---
> > Changes in V2:
> >   - Make decode_trap_cause() more optimization friendly.
> >   - Merge the pathc which introduces do_unexpected_trap() to the
> > current one.
> > ---
> >  xen/arch/riscv/traps.c | 85
> > +++++++++++++++++++++++++++++++++++++++++-
> >  1 file changed, 84 insertions(+), 1 deletion(-)
> > 
> > diff --git a/xen/arch/riscv/traps.c b/xen/arch/riscv/traps.c
> > index ccd3593f5a..f2a1e1ffcf 100644
> > --- a/xen/arch/riscv/traps.c
> > +++ b/xen/arch/riscv/traps.c
> > @@ -4,10 +4,93 @@
> >   *
> >   * 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>
> > +#include <xen/lib.h>
> > 
> > -void do_trap(struct cpu_user_regs *cpu_regs)
> > +static const char *decode_trap_cause(unsigned long cause)
> > +{
> > +    static const char *const trap_causes[] = {
> > +        [CAUSE_MISALIGNED_FETCH] = "Instruction Address
> > Misaligned",
> > +        [CAUSE_FETCH_ACCESS] = "Instruction Access Fault",
> > +        [CAUSE_ILLEGAL_INSTRUCTION] = "Illegal Instruction",
> > +        [CAUSE_BREAKPOINT] = "Breakpoint",
> > +        [CAUSE_MISALIGNED_LOAD] = "Load Address Misaligned",
> > +        [CAUSE_LOAD_ACCESS] = "Load Access Fault",
> > +        [CAUSE_MISALIGNED_STORE] = "Store/AMO Address Misaligned",
> > +        [CAUSE_STORE_ACCESS] = "Store/AMO Access Fault",
> > +        [CAUSE_USER_ECALL] = "Environment Call from U-Mode",
> > +        [CAUSE_SUPERVISOR_ECALL] = "Environment Call from S-Mode",
> > +        [CAUSE_MACHINE_ECALL] = "Environment Call from M-Mode",
> > +        [CAUSE_FETCH_PAGE_FAULT] = "Instruction Page Fault",
> > +        [CAUSE_LOAD_PAGE_FAULT] = "Load Page Fault",
> > +        [CAUSE_STORE_PAGE_FAULT] = "Store/AMO Page Fault",
> > +        [CAUSE_FETCH_GUEST_PAGE_FAULT] = "Instruction Guest Page
> > Fault",
> > +        [CAUSE_LOAD_GUEST_PAGE_FAULT] = "Load Guest Page Fault",
> > +        [CAUSE_VIRTUAL_INST_FAULT] = "Virtualized Instruction
> > Fault",
> > +        [CAUSE_STORE_GUEST_PAGE_FAULT] = "Guest Store/AMO Page
> > Fault",
> > +    };
> > +
> > +    if ( cause < ARRAY_SIZE(trap_causes) && trap_causes[cause] )
> > +        return trap_causes[cause];
> > +    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";
> 
> Wrong string here
> 
> Alistair
Nice catch.
Thanks.
> 
> > +    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);
> > +}
> > +
> > +static void do_unexpected_trap(const struct cpu_user_regs *regs)
> >  {
> > +    unsigned long cause = csr_read(CSR_SCAUSE);
> > +
> > +    early_printk("Unhandled exception: ");
> > +    early_printk(decode_cause(cause));
> > +    early_printk("\n");
> > +
> >      die();
> >  }
> > +
> > +void do_trap(struct cpu_user_regs *cpu_regs)
> > +{
> > +    do_unexpected_trap(cpu_regs);
> > +}
> > --
> > 2.39.0
> > 
> >

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