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-rw-r--r--target/avr/helper.c69
1 files changed, 43 insertions, 26 deletions
diff --git a/target/avr/helper.c b/target/avr/helper.c
index db76452f9a..156dde4e92 100644
--- a/target/avr/helper.c
+++ b/target/avr/helper.c
@@ -28,36 +28,41 @@
 
 bool avr_cpu_exec_interrupt(CPUState *cs, int interrupt_request)
 {
-    bool ret = false;
-    CPUClass *cc = CPU_GET_CLASS(cs);
     AVRCPU *cpu = AVR_CPU(cs);
     CPUAVRState *env = &cpu->env;
 
+    /*
+     * We cannot separate a skip from the next instruction,
+     * as the skip would not be preserved across the interrupt.
+     * Separating the two insn normally only happens at page boundaries.
+     */
+    if (env->skip) {
+        return false;
+    }
+
     if (interrupt_request & CPU_INTERRUPT_RESET) {
         if (cpu_interrupts_enabled(env)) {
             cs->exception_index = EXCP_RESET;
-            cc->tcg_ops->do_interrupt(cs);
+            avr_cpu_do_interrupt(cs);
 
             cs->interrupt_request &= ~CPU_INTERRUPT_RESET;
-
-            ret = true;
+            return true;
         }
     }
     if (interrupt_request & CPU_INTERRUPT_HARD) {
         if (cpu_interrupts_enabled(env) && env->intsrc != 0) {
             int index = ctz32(env->intsrc);
             cs->exception_index = EXCP_INT(index);
-            cc->tcg_ops->do_interrupt(cs);
+            avr_cpu_do_interrupt(cs);
 
             env->intsrc &= env->intsrc - 1; /* clear the interrupt */
             if (!env->intsrc) {
                 cs->interrupt_request &= ~CPU_INTERRUPT_HARD;
             }
-
-            ret = true;
+            return true;
         }
     }
-    return ret;
+    return false;
 }
 
 void avr_cpu_do_interrupt(CPUState *cs)
@@ -102,38 +107,50 @@ bool avr_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
                       MMUAccessType access_type, int mmu_idx,
                       bool probe, uintptr_t retaddr)
 {
-    int prot = 0;
-    MemTxAttrs attrs = {};
+    int prot, page_size = TARGET_PAGE_SIZE;
     uint32_t paddr;
 
     address &= TARGET_PAGE_MASK;
 
     if (mmu_idx == MMU_CODE_IDX) {
-        /* access to code in flash */
+        /* Access to code in flash. */
         paddr = OFFSET_CODE + address;
         prot = PAGE_READ | PAGE_EXEC;
-        if (paddr + TARGET_PAGE_SIZE > OFFSET_DATA) {
+        if (paddr >= OFFSET_DATA) {
+            /*
+             * This should not be possible via any architectural operations.
+             * There is certainly not an exception that we can deliver.
+             * Accept probing that might come from generic code.
+             */
+            if (probe) {
+                return false;
+            }
             error_report("execution left flash memory");
             abort();
         }
-    } else if (address < NUMBER_OF_CPU_REGISTERS + NUMBER_OF_IO_REGISTERS) {
-        /*
-         * access to CPU registers, exit and rebuilt this TB to use full access
-         * incase it touches specially handled registers like SREG or SP
-         */
-        AVRCPU *cpu = AVR_CPU(cs);
-        CPUAVRState *env = &cpu->env;
-        env->fullacc = 1;
-        cpu_loop_exit_restore(cs, retaddr);
     } else {
-        /* access to memory. nothing special */
+        /* Access to memory. */
         paddr = OFFSET_DATA + address;
         prot = PAGE_READ | PAGE_WRITE;
+        if (address < NUMBER_OF_CPU_REGISTERS + NUMBER_OF_IO_REGISTERS) {
+            /*
+             * Access to CPU registers, exit and rebuilt this TB to use
+             * full access in case it touches specially handled registers
+             * like SREG or SP.  For probing, set page_size = 1, in order
+             * to force tlb_fill to be called for the next access.
+             */
+            if (probe) {
+                page_size = 1;
+            } else {
+                AVRCPU *cpu = AVR_CPU(cs);
+                CPUAVRState *env = &cpu->env;
+                env->fullacc = 1;
+                cpu_loop_exit_restore(cs, retaddr);
+            }
+        }
     }
 
-    tlb_set_page_with_attrs(cs, address, paddr, attrs, prot,
-                            mmu_idx, TARGET_PAGE_SIZE);
-
+    tlb_set_page(cs, address, paddr, prot, mmu_idx, page_size);
     return true;
 }