The patch introduces stuff needed to decode a reason of an
exception.
Signed-off-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
---
Changes in V8:
- fix typo in return string from decode_reserved_interrupt_cause
- add Acked-by: Alistair Francis <alistair.francis@wdc.com>
---
Changes in V7:
- Nothing changed. Only rebase.
---
Changes in V6:
- Remove usage of LINK_TO_LOAD() due to the MMU being enabled first.
- Change early_printk() to printk()
---
Changes in V5:
- Remove <xen/error.h> from riscv/traps/c as nothing would require
inclusion.
- decode_reserved_interrupt_cause(), decode_interrupt_cause(), decode_cause, do_unexpected_trap()
were made as static they are expected to be used only in traps.c
- use LINK_TO_LOAD() for addresses which can be linker time relative.
---
Changes in V4:
- fix string in decode_reserved_interrupt_cause()
---
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 | 84 +++++++++++++++++++++++++++++++++++++++++-
1 file changed, 83 insertions(+), 1 deletion(-)
diff --git a/xen/arch/riscv/traps.c b/xen/arch/riscv/traps.c
index ccd3593f5a..a2b63d579b 100644
--- a/xen/arch/riscv/traps.c
+++ b/xen/arch/riscv/traps.c
@@ -4,10 +4,92 @@
*
* RISC-V Trap handlers
*/
+
+#include <xen/lib.h>
+
+#include <asm/csr.h>
+#include <asm/early_printk.h>
#include <asm/processor.h>
#include <asm/traps.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";
+}
+
+static 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 External Interrupt";
+ default:
+ return "UNKNOWN IRQ type";
+ }
+}
+
+static 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);
+ }
+}
+
+static 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);
+
+ printk("Unhandled exception: %s\n", decode_cause(cause));
+
die();
}
+
+void do_trap(struct cpu_user_regs *cpu_regs)
+{
+ do_unexpected_trap(cpu_regs);
+}
--
2.41.0