add test11

1 files changed, 338 insertions, 0 deletions

diff --git a/test11-buserr.c b/test11-buserr.c
new file mode 100644
index 0000000..fcc3b3e
--- /dev/null
+++ b/test11-buserr.c
@@ -0,0 +1,338 @@
+/* See how various faults are reported and recovered
+ */
+#include "armv7m.h"
+
+void inst_skip(uint32_t *sp);
+
+static
+volatile unsigned fault_type;
+
+static
+void check_fault(unsigned expect)
+{
+    unsigned actual = fault_type;
+    puts("# Fault: ");
+    switch(actual) {
+    case 0: puts("None\n"); break;
+    case 1: puts("Mem\n"); break;
+    case 2: puts("Bus\n"); break;
+    case 3: puts("Usage\n"); break;
+    default: puthex(actual);
+    }
+
+    if(expect!=actual)
+        puts("not ");
+    puts("ok - ");
+    puthex(actual);
+    puts(" = ");
+    puthex(expect);
+    putc('\n');
+    fault_type = 0;
+}
+
+static
+void set_fault(unsigned actual)
+{
+    if(fault_type) {
+        puts("Secondary fault ");
+        puthex(actual);
+        putc('\n');
+        abort();
+    }
+    fault_type = actual;
+}
+
+static
+void hard(void)
+{
+    puts("Unexpected HardFault\n");
+    abort();
+}
+
+void bus(uint32_t *sp)
+{
+    uint32_t sts, addr;
+
+    set_fault(2);
+
+    sts = in32(SCB(0xd28));
+    addr= in32(SCB(0xd38));
+
+    out32(SCB(0xd28), 0xff00); /* W1C */
+    out32(SCB(0xd38), 0);
+
+    puts("BusFault: ");
+    puthex(sts);
+    putc(' ');
+    if(sts&0x8000) {
+        puthex(addr);
+        putc(' ');
+    }
+    if(sts&0x1000)
+        puts("STKERR ");
+    if(sts&0x0800)
+        puts("UNSTKERR ");
+    if(sts&0x0400)
+        puts("IMPRECISERR ");
+    if(sts&0x0200)
+        puts("PRECISERR ");
+    if(sts&0x0100)
+        puts("IBUSERR ");
+
+    putc('\n');
+
+    if(sts&0x0200) {
+        /* precise faults would return to the faulting
+         * instruction, which would then fault again
+         * since we change nothing, so skip it.
+         */
+        puts("From: ");
+        puthex(sp[6]);
+        if(sp[6]<0xfffffff0)
+            inst_skip(sp);
+    } else {
+        puts("From before: ");
+        puthex(sp[6]);
+    }
+    putc('\n');
+
+    if(sp[6]>=0xfffffff0) {
+        /* evil hack since we know this was a bx instruction */
+        sp[6] = sp[5]&~1; /* jump to LR */
+    }
+}
+
+static __attribute__((naked))
+void bus_entry(void)
+{
+    asm("mov r0, sp");
+    asm("b bus");
+}
+
+void mem(uint32_t *sp)
+{
+    uint32_t sts, addr;
+
+    set_fault(1);
+
+    sts = in32(SCB(0xd28));
+    addr= in32(SCB(0xd34));
+
+    out32(SCB(0xd28), 0xff); /* W1C */
+
+    puts("MemFault: ");
+    puthex(sts);
+    putc(' ');
+    if(sts&0x80) {
+        puthex(addr);
+        putc(' ');
+    }
+    if(sts&0x08)
+        puts("MSTKERR ");
+    if(sts&0x04)
+        puts("MUNSTKERR ");
+    if(sts&0x02)
+        puts("DACCVIOL ");
+    if(sts&0x01)
+        puts("IACCVIOL ");
+
+    putc('\n');
+
+    puts("From: ");
+    puthex(sp[6]);
+    putc('\n');
+
+    if(sp[6]>=0xfffffff0) {
+        /* evil hack since we know this was a bx instruction */
+        sp[6] = sp[5]&~1; /* jump to LR */
+    } else {
+        inst_skip(sp);
+    }
+}
+
+static __attribute__((naked))
+void mem_entry(void)
+{
+    asm("mov r0, sp");
+    asm("b mem");
+}
+
+
+void usage(uint32_t *sp)
+{
+    uint32_t sts;
+
+    set_fault(1);
+
+    sts = in32(SCB(0xd28));
+
+    out32(SCB(0xd28), 0xffff0000); /* W1C */
+
+    puts("UsageFault: ");
+    if(sts&0x2000000)
+        puts("DIVBYZERO ");
+    if(sts&0x1000000)
+        puts("UNALIGNED ");
+    if(sts&0x80000)
+        puts("NOCP ");
+    if(sts&0x40000)
+        puts("INVPC ");
+    if(sts&0x20000)
+        puts("INVSTATE ");
+    if(sts&0x10000)
+        puts("UNDEFINSTR ");
+
+    putc('\n');
+
+    puts("From: ");
+    puthex(sp[6]);
+    putc('\n');
+
+    if(sts&0x20000) {
+        abort(); /* attempt to execute ARM mode */
+    }
+
+    inst_skip(sp);
+}
+
+static __attribute__((naked))
+void usage_entry(void)
+{
+    asm("mov r0, sp");
+    asm("b usage");
+}
+
+static __attribute__((naked))
+void jumpff(uint32_t x)
+{
+    (void)x;
+    /* evilness
+     * 'blx' would fault before updating 'lr' anyway, so use 'bx'
+     * to be clear.
+     * We will return using the link register from our caller.
+     */
+    asm("bx r0");
+    asm("jumpstuck: b jumpstuck");
+}
+
+void main(void)
+{
+    run_table.bus = bus_entry;
+    run_table.mem = mem_entry;
+    run_table.usage = usage_entry;
+    run_table.hard = hard;
+
+    out32(SCB(0xd24), 0x70000); /* Enable Bus, Mem, and Usage Faults */
+
+    puts("# w/o MPU, hits background mapping\n");
+
+    puts("1. Cause BusFault 0xe100ffff\n");
+    out32((void*)0xe100ffff, 0);
+    check_fault(2);
+    puts("Back in Main\n");
+
+    puts("2. Another BusFault 0x10000000\n");
+    out32((void*)0x10000000, 0);
+    check_fault(2);
+    puts("Back in Main\n");
+
+    puts("3. Another BusFault 0x01000000\n");
+    out32((void*)0x01000000, 0);
+    check_fault(2);
+    puts("Back in Main\n");
+
+    puts("4. Another BusFault 0xfffffffe\n");
+    out32((void*)0xfffffffe, 0);
+    check_fault(2);
+    puts("Back in Main\n");
+
+// this jump works, and TI has hidden so data here
+//    puts("5. MemFault (jump to 0x01000001)\n");
+//    jumpff(0x01000001);
+//    check_fault(1);
+//    puts("Back in Main\n");
+
+    puts("5. MemFault (jump to 0xfffffff9)\n");
+    jumpff(0xfffffff9);
+    check_fault(1);
+    puts("Back in Main\n");
+
+    puts("# Enable MPU, but not for privlaged"
+         " still hits background mapping\n");
+    enable_mpu(1,0,0);
+
+    puts("6. Cause BusFault 0xe100ffff\n");
+    out32((void*)0xe100ffff, 0);
+    check_fault(2);
+    puts("Back in Main\n");
+
+    puts("7. Another BusFault 0x10000000\n");
+    out32((void*)0x10000000, 0);
+    check_fault(2);
+    puts("Back in Main\n");
+
+    puts("8. Another BusFault 0x01000000\n");
+    out32((void*)0x01000000, 0);
+    check_fault(2);
+    puts("Back in Main\n");
+
+    puts("9. Another BusFault 0xfffffffe\n");
+    out32((void*)0xfffffffe, 0);
+    check_fault(2);
+    puts("Back in Main\n");
+
+// this jump works, and TI has hidden so data here
+//    puts("5. MemFault (jump to 0x01000001)\n");
+//    jumpff(0x01000001);
+//    check_fault(1);
+//    puts("Back in Main\n");
+
+    puts("10. MemFault (jump to 0xfffffff9)\n");
+    jumpff(0xfffffff9);
+    check_fault(1);
+    puts("Back in Main\n");
+
+    // ROM region is made larger than actual rom to pass through 0x05000000
+    set_mpu(0, 0x00000000, 0x08000000, MPU_NORMAL|MPU_RORO);
+    set_mpu(1, 0x20000000, 0x00080000, MPU_NORMAL|MPU_RWRW|MPU_XN);
+    set_mpu(2, 0x400fe000, 0x00100000, MPU_DEVICE|MPU_RWRW|MPU_XN);
+    set_mpu(3, 0xe000e000, 0x00001000, MPU_DEVICE|MPU_RWRW|MPU_XN);
+    // Allow through access to unconnected address space
+    set_mpu(4, 0xe100e000, 0x00020000, MPU_DEVICE|MPU_RWRW|MPU_XN);
+
+    puts("# Enable MPU, including privlaged\n");
+    enable_mpu(1,1,0);
+
+    // MPU allows through, but no one is home == BusFault
+    puts("11. Cause BusFault 0xe100ffff\n");
+    out32((void*)0xe100ffff, 0);
+    check_fault(2);
+    puts("Back in Main\n");
+
+    puts("12. Another MemFault 0x10000000\n");
+    out32((void*)0x10000000, 0);
+    check_fault(1);
+    puts("Back in Main\n");
+
+    // MPU allows through, no one is home, but still MemFault...?
+    puts("13. Another MemFault 0x05000000\n");
+    out32((void*)0x05000000, 0);
+    check_fault(1);
+    puts("Back in Main\n");
+
+    puts("14. Another MemFault 0xfffffffe\n");
+    out32((void*)0xfffffffe, 0);
+    check_fault(1);
+    puts("Back in Main\n");
+
+// this jump works, and TI has hidden so data here
+//    puts("5. MemFault (jump to 0x01000001)\n");
+//    jumpff(0x01000001);
+//    check_fault(1);
+//    puts("Back in Main\n");
+
+    puts("15. MemFault (jump to 0xfffffff9)\n");
+    jumpff(0xfffffff9);
+    check_fault(1);
+    puts("Back in Main\n");
+}