Changeset 70259a55 in mainline

Timestamp:

2018-09-11T21:01:08Z (6 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

e38ff16

Parents:

d2c91ab

Message:

ia64: Use appropriate imm21 operand with BREAK

This commit changes the imm21 used with the BREAK instruction to conform
to the IA-64 Software Conventions and Runtime Architecture Guide. This
is necessary to be able to distinguish syscalls from compiler-generated
calls to architected software interrupts (e.g. integer divide by zero).

In order to be able to test the used immediate in break_instruction(),
we extend istate_t to hold the CR.IIM register.

Files:

• kernel/arch/ia64/include/arch/istate_struct.h (modified) (2 diffs)
• kernel/arch/ia64/src/interrupt.c (modified) (1 diff)
• kernel/arch/ia64/src/ivt.S (modified) (3 diffs)
• uspace/lib/c/arch/ia64/src/syscall.S (modified) (1 diff)

kernel/arch/ia64/include/arch/istate_struct.h

@@ -72 +72 @@
 #define ISTATE_OFFSET_CR_IPSR           0x230
 #define ISTATE_OFFSET_CR_IIP            0x238
-#define ISTATE_OFFSET_PR                0x240
-#define ISTATE_OFFSET_SP                0x248
-#define ISTATE_OFFSET_IN0               0x250
-#define ISTATE_OFFSET_IN1               0x258
-#define ISTATE_OFFSET_IN2               0x260
-#define ISTATE_OFFSET_IN3               0x268
-#define ISTATE_OFFSET_IN4               0x270
-#define ISTATE_OFFSET_IN5               0x278
-#define ISTATE_OFFSET_IN6               0x280
+#define ISTATE_OFFSET_CR_IIM            0x240
+#define ISTATE_OFFSET_PR                0x248
+#define ISTATE_OFFSET_SP                0x250
+#define ISTATE_OFFSET_IN0               0x258
+#define ISTATE_OFFSET_IN1               0x260
+#define ISTATE_OFFSET_IN2               0x268
+#define ISTATE_OFFSET_IN3               0x270
+#define ISTATE_OFFSET_IN4               0x278
+#define ISTATE_OFFSET_IN5               0x280
+#define ISTATE_OFFSET_IN6               0x288
 #define ISTATE_SIZE                     0x290
 
@@ -138 +139 @@
         psr_t cr_ipsr;
         uintptr_t cr_iip;
+        uint64_t cr_iim;
         uint64_t pr;
         uintptr_t sp;

kernel/arch/ia64/src/interrupt.c

@@ -195 +195 @@
 }
 
+
+#define BREAK_IMM_SYSCALL       0x40000U
+
 /** Handle syscall. */
 sysarg_t break_instruction(unsigned int n, istate_t *istate)
 {
         sysarg_t ret;
+
+        if (istate->cr_iim != BREAK_IMM_SYSCALL) {
+                fault_if_from_uspace(istate, "Unknown software interrupt: %x",
+                    (uint32_t) istate->cr_iim);
+                panic_badtrap(istate, n, "Interruption: %#hx (%s).",
+                    (uint16_t) n, vector_to_string(n));
+        }
 
         /*

kernel/arch/ia64/src/ivt.S

@@ -186 +186 @@
         st8 [r31] = r29, -STACK_ITEM_SIZE ;;    /* save predicate registers */
 
+        mov r29 = cr.iim ;;
+        st8 [r31] = r29, -STACK_ITEM_SIZE ;;    /* save cr.iim */
+
         st8 [r31] = r24, -STACK_ITEM_SIZE ;;    /* save cr.iip */
         st8 [r31] = r25, -STACK_ITEM_SIZE ;;    /* save cr.ipsr */
@@ -274 +277 @@
         ld8 r25 = [r31], +STACK_ITEM_SIZE ;;    /* load cr.ipsr */
         ld8 r24 = [r31], +STACK_ITEM_SIZE ;;    /* load cr.iip */
+        ld8 r29 = [r31], +STACK_ITEM_SIZE ;;    /* load cr.iim */
 
         mov cr.iip = r24;;
@@ -279 +283 @@
         mov cr.isr = r27
         mov cr.ifa = r28
+        mov cr.iim = r29
 
         /* Set up FPU as in exception. */

uspace/lib/c/arch/ia64/src/syscall.S

@@ -29 +29 @@
 #include <abi/asmtool.h>
 
-/**
- * Immediate operand for break instruction.
- * Be carefull about the value as Ski simulator
- * is somewhat sensitive to its value.
+/*
+ * IA-64 Software Conventions and Runtime Architecture Guide mandates that
+ * the zero-extended imm21 operand of the BREAK instruction is used as follows:
  *
- * 0 will be confused with Ski breakpoint.
- * And higher values will be confused with SSC's.
+ * MSB | Purpose
+ * ----+--------
+ * 000 | Reserved for architected software interrupts
+ * 001 | Available for application use as software interrupts
+ * 01x | Reserved for debugger breakpoints
+ * 1xx | Reserved for definition by each ABI
  */
-#define SYSCALL_IMM     1
+#define SYSCALL_IMM     0x40000
 
 FUNCTION_BEGIN(__syscall)