mips: fix gaffe when removing dynamic array allocation
[fw/openocd] / src / target / cortex_a8.c
index 730cd33e190c0d022aa975d95651dca578747edb..b006e81a64df7f91547fce2a4020b70d2042c083 100644 (file)
 #include "config.h"
 #endif
 
+#include "breakpoints.h"
 #include "cortex_a8.h"
-#include "armv7a.h"
-#include "armv4_5.h"
-
+#include "register.h"
 #include "target_request.h"
 #include "target_type.h"
 
@@ -238,22 +237,26 @@ static int cortex_a8_dap_read_coreregister_u32(struct target *target,
        struct armv7a_common *armv7a = target_to_armv7a(target);
        struct swjdp_common *swjdp = &armv7a->swjdp_info;
 
-       if (reg > 16)
+       if (reg > 17)
                return retval;
 
        if (reg < 15)
        {
-               /* Rn to DCCTX, MCR p14, 0, Rd, c0, c5, 0,  0xEE000E15 */
+               /* Rn to DCCTX, "MCR p14, 0, Rn, c0, c5, 0"  0xEE00nE15 */
                cortex_a8_exec_opcode(target, ARMV4_5_MCR(14, 0, reg, 0, 5, 0));
        }
        else if (reg == 15)
        {
+               /* "MOV r0, r15"; then move r0 to DCCTX */
                cortex_a8_exec_opcode(target, 0xE1A0000F);
                cortex_a8_exec_opcode(target, ARMV4_5_MCR(14, 0, 0, 0, 5, 0));
        }
-       else if (reg == 16)
+       else
        {
-               cortex_a8_exec_opcode(target, ARMV4_5_MRS(0, 0));
+               /* "MRS r0, CPSR" or "MRS r0, SPSR"
+                * then move r0 to DCCTX
+                */
+               cortex_a8_exec_opcode(target, ARMV4_5_MRS(0, reg & 1));
                cortex_a8_exec_opcode(target, ARMV4_5_MCR(14, 0, 0, 0, 5, 0));
        }
 
@@ -267,11 +270,13 @@ static int cortex_a8_dap_read_coreregister_u32(struct target *target,
 
        retval = mem_ap_read_atomic_u32(swjdp,
                        armv7a->debug_base + CPUDBG_DTRTX, value);
+       LOG_DEBUG("read DCC 0x%08" PRIx32, *value);
 
        return retval;
 }
 
-static int cortex_a8_dap_write_coreregister_u32(struct target *target, uint32_t value, int regnum)
+static int cortex_a8_dap_write_coreregister_u32(struct target *target,
+               uint32_t value, int regnum)
 {
        int retval = ERROR_OK;
        uint8_t Rd = regnum&0xFF;
@@ -291,29 +296,39 @@ static int cortex_a8_dap_write_coreregister_u32(struct target *target, uint32_t
                cortex_a8_exec_opcode(target, ARMV4_5_MRC(14, 0, 0, 0, 5, 0));
        }
 
-       if (Rd > 16)
+       if (Rd > 17)
                return retval;
 
        /* Write to DCCRX */
+       LOG_DEBUG("write DCC 0x%08" PRIx32, value);
        retval = mem_ap_write_u32(swjdp,
                        armv7a->debug_base + CPUDBG_DTRRX, value);
 
        if (Rd < 15)
        {
-               /* DCCRX to Rd, MCR p14, 0, Rd, c0, c5, 0,  0xEE000E15 */
+               /* DCCRX to Rn, "MCR p14, 0, Rn, c0, c5, 0", 0xEE00nE15 */
                cortex_a8_exec_opcode(target, ARMV4_5_MRC(14, 0, Rd, 0, 5, 0));
        }
        else if (Rd == 15)
        {
+               /* DCCRX to R0, "MCR p14, 0, R0, c0, c5, 0", 0xEE000E15
+                * then "mov r15, r0"
+                */
                cortex_a8_exec_opcode(target, ARMV4_5_MRC(14, 0, 0, 0, 5, 0));
                cortex_a8_exec_opcode(target, 0xE1A0F000);
        }
-       else if (Rd == 16)
+       else
        {
+               /* DCCRX to R0, "MCR p14, 0, R0, c0, c5, 0", 0xEE000E15
+                * then "MSR CPSR_cxsf, r0" or "MSR SPSR_cxsf, r0" (all fields)
+                */
                cortex_a8_exec_opcode(target, ARMV4_5_MRC(14, 0, 0, 0, 5, 0));
-               cortex_a8_exec_opcode(target, ARMV4_5_MSR_GP(0, 0xF, 0));
-               /* Execute a PrefetchFlush instruction through the ITR. */
-               cortex_a8_exec_opcode(target, ARMV4_5_MCR(15, 0, 0, 7, 5, 4));
+               cortex_a8_exec_opcode(target, ARMV4_5_MSR_GP(0, 0xF, Rd & 1));
+
+               /* "Prefetch flush" after modifying execution status in CPSR */
+               if (Rd == 16)
+                       cortex_a8_exec_opcode(target,
+                                       ARMV4_5_MCR(15, 0, 0, 7, 5, 4));
        }
 
        return retval;
@@ -442,7 +457,7 @@ static int cortex_a8_resume(struct target *target, int current,
                uint32_t address, int handle_breakpoints, int debug_execution)
 {
        struct armv7a_common *armv7a = target_to_armv7a(target);
-       struct armv4_5_common_s *armv4_5 = &armv7a->armv4_5_common;
+       struct arm *armv4_5 = &armv7a->armv4_5_common;
        struct swjdp_common *swjdp = &armv7a->swjdp_info;
 
 //     struct breakpoint *breakpoint = NULL;
@@ -481,8 +496,7 @@ static int cortex_a8_resume(struct target *target, int current,
 
        /* current = 1: continue on current pc, otherwise continue at <address> */
        resume_pc = buf_get_u32(
-                       ARMV7A_CORE_REG_MODE(armv4_5->core_cache,
-                               armv4_5->core_mode, 15).value,
+                       armv4_5->core_cache->reg_list[15].value,
                        0, 32);
        if (!current)
                resume_pc = address;
@@ -490,28 +504,30 @@ static int cortex_a8_resume(struct target *target, int current,
        /* Make sure that the Armv7 gdb thumb fixups does not
         * kill the return address
         */
-       if (armv7a->core_state == ARMV7A_STATE_ARM)
+       switch (armv4_5->core_state)
        {
+       case ARMV4_5_STATE_ARM:
                resume_pc &= 0xFFFFFFFC;
-       }
-       /* When the return address is loaded into PC
-        * bit 0 must be 1 to stay in Thumb state
-        */
-       if (armv7a->core_state == ARMV7A_STATE_THUMB)
-       {
+               break;
+       case ARMV4_5_STATE_THUMB:
+       case ARM_STATE_THUMB_EE:
+               /* When the return address is loaded into PC
+                * bit 0 must be 1 to stay in Thumb state
+                */
                resume_pc |= 0x1;
+               break;
+       case ARMV4_5_STATE_JAZELLE:
+               LOG_ERROR("How do I resume into Jazelle state??");
+               return ERROR_FAIL;
        }
        LOG_DEBUG("resume pc = 0x%08" PRIx32, resume_pc);
-       buf_set_u32(ARMV7A_CORE_REG_MODE(armv4_5->core_cache,
-                               armv4_5->core_mode, 15).value,
+       buf_set_u32(armv4_5->core_cache->reg_list[15].value,
                        0, 32, resume_pc);
-       ARMV7A_CORE_REG_MODE(armv4_5->core_cache,
-                       armv4_5->core_mode, 15).dirty = 1;
-       ARMV7A_CORE_REG_MODE(armv4_5->core_cache,
-                       armv4_5->core_mode, 15).valid = 1;
+       armv4_5->core_cache->reg_list[15].dirty = 1;
+       armv4_5->core_cache->reg_list[15].valid = 1;
 
        cortex_a8_restore_context(target);
-//     arm7_9_restore_context(target); TODO Context is currently NOT Properly restored
+
 #if 0
        /* the front-end may request us not to handle breakpoints */
        if (handle_breakpoints)
@@ -539,7 +555,7 @@ static int cortex_a8_resume(struct target *target, int current,
        target->state = TARGET_RUNNING;
 
        /* registers are now invalid */
-       armv4_5_invalidate_core_regs(target);
+       register_cache_invalidate(armv4_5->core_cache);
 
        if (!debug_execution)
        {
@@ -567,8 +583,9 @@ static int cortex_a8_debug_entry(struct target *target)
        struct working_area *regfile_working_area = NULL;
        struct cortex_a8_common *cortex_a8 = target_to_cortex_a8(target);
        struct armv7a_common *armv7a = target_to_armv7a(target);
-       struct armv4_5_common_s *armv4_5 = &armv7a->armv4_5_common;
+       struct arm *armv4_5 = &armv7a->armv4_5_common;
        struct swjdp_common *swjdp = &armv7a->swjdp_info;
+       struct reg *reg;
 
        LOG_DEBUG("dscr = 0x%08" PRIx32, cortex_a8->cpudbg_dscr);
 
@@ -605,6 +622,9 @@ static int cortex_a8_debug_entry(struct target *target)
        /* First load register acessible through core debug port*/
        if (!regfile_working_area)
        {
+               /* FIXME we don't actually need all these registers;
+                * reading them slows us down.  Just R0, PC, CPSR...
+                */
                for (i = 0; i <= 15; i++)
                        cortex_a8_dap_read_coreregister_u32(target,
                                        &regfile[i], i);
@@ -618,32 +638,26 @@ static int cortex_a8_debug_entry(struct target *target)
                target_free_working_area(target, regfile_working_area);
        }
 
+       /* read Current PSR */
        cortex_a8_dap_read_coreregister_u32(target, &cpsr, 16);
        pc = regfile[15];
        dap_ap_select(swjdp, swjdp_debugap);
        LOG_DEBUG("cpsr: %8.8" PRIx32, cpsr);
 
-       armv4_5->core_mode = cpsr & 0x1F;
-       armv7a->core_state = (cpsr & 0x20)?ARMV7A_STATE_THUMB:ARMV7A_STATE_ARM;
+       arm_set_cpsr(armv4_5, cpsr);
 
+       /* update cache */
        for (i = 0; i <= ARM_PC; i++)
        {
-               buf_set_u32(ARMV7A_CORE_REG_MODE(armv4_5->core_cache,
-                                       armv4_5->core_mode, i).value,
-                               0, 32, regfile[i]);
-               ARMV7A_CORE_REG_MODE(armv4_5->core_cache,
-                               armv4_5->core_mode, i).valid = 1;
-               ARMV7A_CORE_REG_MODE(armv4_5->core_cache,
-                               armv4_5->core_mode, i).dirty = 0;
-       }
-       buf_set_u32(ARMV7A_CORE_REG_MODE(armv4_5->core_cache,
-                               armv4_5->core_mode, 16).value,
-                       0, 32, cpsr);
-       ARMV7A_CORE_REG_MODE(armv4_5->core_cache, armv4_5->core_mode, 16).valid = 1;
-       ARMV7A_CORE_REG_MODE(armv4_5->core_cache, armv4_5->core_mode, 16).dirty = 0;
+               reg = arm_reg_current(armv4_5, i);
+
+               buf_set_u32(reg->value, 0, 32, regfile[i]);
+               reg->valid = 1;
+               reg->dirty = 0;
+       }
 
        /* Fixup PC Resume Address */
-       if (armv7a->core_state == ARMV7A_STATE_THUMB)
+       if (cpsr & (1 << 5))
        {
                // T bit set for Thumb or ThumbEE state
                regfile[ARM_PC] -= 4;
@@ -653,15 +667,12 @@ static int cortex_a8_debug_entry(struct target *target)
                // ARM state
                regfile[ARM_PC] -= 8;
        }
-       buf_set_u32(ARMV7A_CORE_REG_MODE(armv4_5->core_cache,
-                               armv4_5->core_mode, ARM_PC).value,
-                       0, 32, regfile[ARM_PC]);
 
-       ARMV7A_CORE_REG_MODE(armv4_5->core_cache, armv4_5->core_mode, 0)
-               .dirty = ARMV7A_CORE_REG_MODE(armv4_5->core_cache,
-                               armv4_5->core_mode, 0).valid;
-       ARMV7A_CORE_REG_MODE(armv4_5->core_cache, armv4_5->core_mode, 15)
-               .dirty = ARMV7A_CORE_REG_MODE(armv4_5->core_cache,
+       reg = armv4_5->core_cache->reg_list + 15;
+       buf_set_u32(reg->value, 0, 32, regfile[ARM_PC]);
+       reg->dirty = reg->valid;
+       ARMV4_5_CORE_REG_MODE(armv4_5->core_cache, armv4_5->core_mode, 15)
+               .dirty = ARMV4_5_CORE_REG_MODE(armv4_5->core_cache,
                                armv4_5->core_mode, 15).valid;
 
 #if 0
@@ -724,7 +735,7 @@ static int cortex_a8_step(struct target *target, int current, uint32_t address,
                int handle_breakpoints)
 {
        struct armv7a_common *armv7a = target_to_armv7a(target);
-       struct armv4_5_common_s *armv4_5 = &armv7a->armv4_5_common;
+       struct arm *armv4_5 = &armv7a->armv4_5_common;
        struct breakpoint *breakpoint = NULL;
        struct breakpoint stepbreakpoint;
 
@@ -739,13 +750,13 @@ static int cortex_a8_step(struct target *target, int current, uint32_t address,
        /* current = 1: continue on current pc, otherwise continue at <address> */
        if (!current)
        {
-               buf_set_u32(ARMV7A_CORE_REG_MODE(armv4_5->core_cache,
+               buf_set_u32(ARMV4_5_CORE_REG_MODE(armv4_5->core_cache,
                                        armv4_5->core_mode, ARM_PC).value,
                                0, 32, address);
        }
        else
        {
-               address = buf_get_u32(ARMV7A_CORE_REG_MODE(armv4_5->core_cache,
+               address = buf_get_u32(ARMV4_5_CORE_REG_MODE(armv4_5->core_cache,
                                        armv4_5->core_mode, ARM_PC).value,
                                0, 32);
        }
@@ -757,7 +768,8 @@ static int cortex_a8_step(struct target *target, int current, uint32_t address,
        handle_breakpoints = 1;
        if (handle_breakpoints) {
                breakpoint = breakpoint_find(target,
-                               buf_get_u32(ARMV7A_CORE_REG_MODE(armv4_5->core_cache,
+                               buf_get_u32(ARMV4_5_CORE_REG_MODE(
+                                       armv4_5->core_cache,
                                        armv4_5->core_mode, 15).value,
                        0, 32));
                if (breakpoint)
@@ -766,7 +778,8 @@ static int cortex_a8_step(struct target *target, int current, uint32_t address,
 
        /* Setup single step breakpoint */
        stepbreakpoint.address = address;
-       stepbreakpoint.length = (armv7a->core_state == ARMV7A_STATE_THUMB) ? 2 : 4;
+       stepbreakpoint.length = (armv4_5->core_state == ARMV4_5_STATE_THUMB)
+                       ? 2 : 4;
        stepbreakpoint.type = BKPT_HARD;
        stepbreakpoint.set = 0;
 
@@ -801,29 +814,84 @@ static int cortex_a8_step(struct target *target, int current, uint32_t address,
 
 static int cortex_a8_restore_context(struct target *target)
 {
-       int i;
        uint32_t value;
        struct armv7a_common *armv7a = target_to_armv7a(target);
-       struct armv4_5_common_s *armv4_5 = &armv7a->armv4_5_common;
+       struct reg_cache *cache = armv7a->armv4_5_common.core_cache;
+       unsigned max = cache->num_regs;
+       struct reg *r;
+       bool flushed, flush_cpsr = false;
 
        LOG_DEBUG(" ");
 
        if (armv7a->pre_restore_context)
                armv7a->pre_restore_context(target);
 
-       for (i = 15; i >= 0; i--)
-       {
-               if (ARMV7A_CORE_REG_MODE(armv4_5->core_cache,
-                                       armv4_5->core_mode, i).dirty)
-               {
-                       value = buf_get_u32(ARMV7A_CORE_REG_MODE(armv4_5->core_cache,
-                                               armv4_5->core_mode, i).value,
-                                       0, 32);
+       /* Flush all dirty registers from the cache, one mode at a time so
+        * that we write CPSR as little as possible.  Save CPSR and R0 for
+        * last; they're used to change modes and write other registers.
+        *
+        * REVISIT be smarter:  save eventual mode for last loop, don't
+        * need to write CPSR an extra time.
+        */
+       do {
+               enum armv4_5_mode mode = ARMV4_5_MODE_ANY;
+               unsigned i;
+
+               flushed = false;
+
+               /* write dirty non-{R0,CPSR} registers sharing the same mode */
+               for (i = max - 1, r = cache->reg_list + 1; i > 0; i--, r++) {
+                       struct arm_reg *reg;
+
+                       if (!r->dirty || r == armv7a->armv4_5_common.cpsr)
+                               continue;
+                       reg = r->arch_info;
+
                        /* TODO Check return values */
-                       cortex_a8_dap_write_coreregister_u32(target, value, i);
+
+                       /* Pick a mode and update CPSR; else ignore this
+                        * register if it's for a different mode than what
+                        * we're handling on this pass.
+                        *
+                        * REVISIT don't distinguish SYS and USR modes.
+                        *
+                        * FIXME if we restore from FIQ mode, R8..R12 will
+                        * get wrongly flushed onto FIQ shadows...
+                        */
+                       if (mode == ARMV4_5_MODE_ANY) {
+                               mode = reg->mode;
+                               if (mode != ARMV4_5_MODE_ANY) {
+                                       cortex_a8_dap_write_coreregister_u32(
+                                                       target, mode, 16);
+                                       flush_cpsr = true;
+                               }
+                       } else if (mode != reg->mode)
+                               continue;
+
+                       /* Write this register */
+                       value = buf_get_u32(r->value, 0, 32);
+                       cortex_a8_dap_write_coreregister_u32(target, value,
+                                       (reg->num == 16) ? 17 : reg->num);
+                       r->dirty = false;
+                       flushed = true;
                }
+
+       } while (flushed);
+
+       /* now flush CPSR if needed ... */
+       r = armv7a->armv4_5_common.cpsr;
+       if (flush_cpsr || r->dirty) {
+               value = buf_get_u32(r->value, 0, 32);
+               cortex_a8_dap_write_coreregister_u32(target, value, 16);
+               r->dirty = false;
        }
 
+       /* ... and R0 always (it was dirtied when we saved context) */
+       r = cache->reg_list + 0;
+       value = buf_get_u32(r->value, 0, 32);
+       cortex_a8_dap_write_coreregister_u32(target, value, 0);
+       r->dirty = false;
+
        if (armv7a->post_restore_context)
                armv7a->post_restore_context(target);
 
@@ -839,7 +907,7 @@ static int cortex_a8_load_core_reg_u32(struct target *target, int num,
                armv4_5_mode_t mode, uint32_t * value)
 {
        int retval;
-       struct armv4_5_common_s *armv4_5 = target_to_armv4_5(target);
+       struct arm *armv4_5 = target_to_armv4_5(target);
 
        if ((num <= ARM_CPSR))
        {
@@ -860,13 +928,13 @@ static int cortex_a8_load_core_reg_u32(struct target *target, int num,
 
        /* Register other than r0 - r14 uses r0 for access */
        if (num > 14)
-               ARMV7A_CORE_REG_MODE(armv4_5->core_cache,
+               ARMV4_5_CORE_REG_MODE(armv4_5->core_cache,
                                armv4_5->core_mode, 0).dirty =
-                       ARMV7A_CORE_REG_MODE(armv4_5->core_cache,
+                       ARMV4_5_CORE_REG_MODE(armv4_5->core_cache,
                                armv4_5->core_mode, 0).valid;
-       ARMV7A_CORE_REG_MODE(armv4_5->core_cache,
+       ARMV4_5_CORE_REG_MODE(armv4_5->core_cache,
                                armv4_5->core_mode, 15).dirty =
-                       ARMV7A_CORE_REG_MODE(armv4_5->core_cache,
+                       ARMV4_5_CORE_REG_MODE(armv4_5->core_cache,
                                armv4_5->core_mode, 15).valid;
 
        return ERROR_OK;
@@ -877,7 +945,7 @@ static int cortex_a8_store_core_reg_u32(struct target *target, int num,
 {
        int retval;
 //     uint32_t reg;
-       struct armv4_5_common_s *armv4_5 = target_to_armv4_5(target);
+       struct arm *armv4_5 = target_to_armv4_5(target);
 
 #ifdef ARMV7_GDB_HACKS
        /* If the LR register is being modified, make sure it will put us
@@ -896,9 +964,9 @@ static int cortex_a8_store_core_reg_u32(struct target *target, int num,
                if (retval != ERROR_OK)
                {
                        LOG_ERROR("JTAG failure %i", retval);
-                       ARMV7A_CORE_REG_MODE(armv4_5->core_cache,
+                       ARMV4_5_CORE_REG_MODE(armv4_5->core_cache,
                                        armv4_5->core_mode, num).dirty =
-                               ARMV7A_CORE_REG_MODE(armv4_5->core_cache,
+                               ARMV4_5_CORE_REG_MODE(armv4_5->core_cache,
                                        armv4_5->core_mode, num).valid;
                        return ERROR_JTAG_DEVICE_ERROR;
                }
@@ -914,44 +982,118 @@ static int cortex_a8_store_core_reg_u32(struct target *target, int num,
 #endif
 
 
-static int cortex_a8_read_core_reg(struct target *target, int num,
-               enum armv4_5_mode mode)
+static int cortex_a8_write_core_reg(struct target *target, struct reg *r,
+               int num, enum armv4_5_mode mode, uint32_t value);
+
+static int cortex_a8_read_core_reg(struct target *target, struct reg *r,
+               int num, enum armv4_5_mode mode)
 {
        uint32_t value;
        int retval;
-       struct armv4_5_common_s *armv4_5 = target_to_armv4_5(target);
+       struct arm *armv4_5 = target_to_armv4_5(target);
+       struct reg *cpsr_r = NULL;
+       uint32_t cpsr = 0;
+       unsigned cookie = num;
 
-       cortex_a8_dap_read_coreregister_u32(target, &value, num);
+       /* avoid some needless mode changes
+        * FIXME move some of these to shared ARM code...
+        */
+       if (mode != armv4_5->core_mode) {
+               if ((armv4_5->core_mode == ARMV4_5_MODE_SYS)
+                               && (mode == ARMV4_5_MODE_USR))
+                       mode = ARMV4_5_MODE_ANY;
+               else if ((mode != ARMV4_5_MODE_FIQ) && (num <= 12))
+                       mode = ARMV4_5_MODE_ANY;
+
+               if (mode != ARMV4_5_MODE_ANY) {
+                       cpsr_r = armv4_5->cpsr;
+                       cpsr = buf_get_u32(cpsr_r->value, 0, 32);
+                       cortex_a8_write_core_reg(target, cpsr_r,
+                                       16, ARMV4_5_MODE_ANY, mode);
+               }
+       }
 
-       if ((retval = jtag_execute_queue()) != ERROR_OK)
-       {
-               return retval;
+       if (num == 16) {
+               switch (mode) {
+               case ARMV4_5_MODE_USR:
+               case ARMV4_5_MODE_SYS:
+               case ARMV4_5_MODE_ANY:
+                       /* CPSR */
+                       break;
+               default:
+                       /* SPSR */
+                       cookie++;
+                       break;
+               }
        }
 
-       ARMV7A_CORE_REG_MODE(armv4_5->core_cache, mode, num).valid = 1;
-       ARMV7A_CORE_REG_MODE(armv4_5->core_cache, mode, num).dirty = 0;
-       buf_set_u32(ARMV7A_CORE_REG_MODE(armv4_5->core_cache,
-                       mode, num).value, 0, 32, value);
+       cortex_a8_dap_read_coreregister_u32(target, &value, cookie);
+       retval = jtag_execute_queue();
+       if (retval == ERROR_OK) {
+               r->valid = 1;
+               r->dirty = 0;
+               buf_set_u32(r->value, 0, 32, value);
+       }
 
-       return ERROR_OK;
+       if (cpsr_r)
+               cortex_a8_write_core_reg(target, cpsr_r,
+                               16, ARMV4_5_MODE_ANY, cpsr);
+       return retval;
 }
 
-int cortex_a8_write_core_reg(struct target *target, int num,
-               enum armv4_5_mode mode, uint32_t value)
+static int cortex_a8_write_core_reg(struct target *target, struct reg *r,
+               int num, enum armv4_5_mode mode, uint32_t value)
 {
        int retval;
-       struct armv4_5_common_s *armv4_5 = target_to_armv4_5(target);
+       struct arm *armv4_5 = target_to_armv4_5(target);
+       struct reg *cpsr_r = NULL;
+       uint32_t cpsr = 0;
+       unsigned cookie = num;
 
-       cortex_a8_dap_write_coreregister_u32(target, value, num);
-       if ((retval = jtag_execute_queue()) != ERROR_OK)
-       {
-               return retval;
+       /* avoid some needless mode changes
+        * FIXME move some of these to shared ARM code...
+        */
+       if (mode != armv4_5->core_mode) {
+               if ((armv4_5->core_mode == ARMV4_5_MODE_SYS)
+                               && (mode == ARMV4_5_MODE_USR))
+                       mode = ARMV4_5_MODE_ANY;
+               else if ((mode != ARMV4_5_MODE_FIQ) && (num <= 12))
+                       mode = ARMV4_5_MODE_ANY;
+
+               if (mode != ARMV4_5_MODE_ANY) {
+                       cpsr_r = armv4_5->cpsr;
+                       cpsr = buf_get_u32(cpsr_r->value, 0, 32);
+                       cortex_a8_write_core_reg(target, cpsr_r,
+                                       16, ARMV4_5_MODE_ANY, mode);
+               }
        }
 
-       ARMV7A_CORE_REG_MODE(armv4_5->core_cache, mode, num).valid = 1;
-       ARMV7A_CORE_REG_MODE(armv4_5->core_cache, mode, num).dirty = 0;
 
-       return ERROR_OK;
+       if (num == 16) {
+               switch (mode) {
+               case ARMV4_5_MODE_USR:
+               case ARMV4_5_MODE_SYS:
+               case ARMV4_5_MODE_ANY:
+                       /* CPSR */
+                       break;
+               default:
+                       /* SPSR */
+                       cookie++;
+                       break;
+               }
+       }
+
+       cortex_a8_dap_write_coreregister_u32(target, value, cookie);
+       if ((retval = jtag_execute_queue()) == ERROR_OK) {
+               buf_set_u32(r->value, 0, 32, value);
+               r->valid = 1;
+               r->dirty = 0;
+       }
+
+       if (cpsr_r)
+               cortex_a8_write_core_reg(target, cpsr_r,
+                               16, ARMV4_5_MODE_ANY, cpsr);
+       return retval;
 }
 
 
@@ -984,7 +1126,7 @@ static int cortex_a8_set_breakpoint(struct target *target,
                if (brp_i >= cortex_a8->brp_num)
                {
                        LOG_ERROR("ERROR Can not find free Breakpoint Register Pair");
-                       exit(-1);
+                       return ERROR_FAIL;
                }
                breakpoint->set = brp_i + 1;
                if (breakpoint->length == 2)
@@ -1142,11 +1284,12 @@ static int cortex_a8_remove_breakpoint(struct target *target, struct breakpoint
 
 static int cortex_a8_assert_reset(struct target *target)
 {
+       struct armv7a_common *armv7a = target_to_armv7a(target);
 
        LOG_DEBUG(" ");
 
        /* registers are now invalid */
-       armv4_5_invalidate_core_regs(target);
+       register_cache_invalidate(armv7a->armv4_5_common.core_cache);
 
        target->state = TARGET_RESET;
 
@@ -1180,19 +1323,14 @@ static int cortex_a8_read_memory(struct target *target, uint32_t address,
 {
        struct armv7a_common *armv7a = target_to_armv7a(target);
        struct swjdp_common *swjdp = &armv7a->swjdp_info;
-
-       int retval = ERROR_OK;
-
-       /* sanitize arguments */
-       if (((size != 4) && (size != 2) && (size != 1)) || (count == 0) || !(buffer))
-               return ERROR_INVALID_ARGUMENTS;
+       int retval = ERROR_INVALID_ARGUMENTS;
 
        /* cortex_a8 handles unaligned memory access */
 
 // ??? dap_ap_select(swjdp, swjdp_memoryap);
 
-       switch (size)
-       {
+       if (count && buffer) {
+               switch (size) {
                case 4:
                        retval = mem_ap_read_buf_u32(swjdp, buffer, 4 * count, address);
                        break;
@@ -1202,9 +1340,7 @@ static int cortex_a8_read_memory(struct target *target, uint32_t address,
                case 1:
                        retval = mem_ap_read_buf_u8(swjdp, buffer, count, address);
                        break;
-               default:
-                       LOG_ERROR("BUG: we shouldn't get here");
-                       exit(-1);
+               }
        }
 
        return retval;
@@ -1215,17 +1351,12 @@ int cortex_a8_write_memory(struct target *target, uint32_t address,
 {
        struct armv7a_common *armv7a = target_to_armv7a(target);
        struct swjdp_common *swjdp = &armv7a->swjdp_info;
-
-       int retval;
-
-       /* sanitize arguments */
-       if (((size != 4) && (size != 2) && (size != 1)) || (count == 0) || !(buffer))
-               return ERROR_INVALID_ARGUMENTS;
+       int retval = ERROR_INVALID_ARGUMENTS;
 
 // ??? dap_ap_select(swjdp, swjdp_memoryap);
 
-       switch (size)
-       {
+       if (count && buffer) {
+               switch (size) {
                case 4:
                        retval = mem_ap_write_buf_u32(swjdp, buffer, 4 * count, address);
                        break;
@@ -1235,12 +1366,10 @@ int cortex_a8_write_memory(struct target *target, uint32_t address,
                case 1:
                        retval = mem_ap_write_buf_u8(swjdp, buffer, count, address);
                        break;
-               default:
-                       LOG_ERROR("BUG: we shouldn't get here");
-                       exit(-1);
+               }
        }
 
-       if (target->state == TARGET_HALTED)
+       if (retval == ERROR_OK && target->state == TARGET_HALTED)
        {
                /* The Cache handling will NOT work with MMU active, the wrong addresses will be invalidated */
                /* invalidate I-Cache */
@@ -1297,11 +1426,11 @@ static int cortex_a8_dcc_read(struct swjdp_common *swjdp, uint8_t *value, uint8_
 static int cortex_a8_handle_target_request(void *priv)
 {
        struct target *target = priv;
-       if (!target->type->examined)
-               return ERROR_OK;
        struct armv7a_common *armv7a = target_to_armv7a(target);
        struct swjdp_common *swjdp = &armv7a->swjdp_info;
 
+       if (!target_was_examined(target))
+               return ERROR_OK;
        if (!target->dbg_msg_enabled)
                return ERROR_OK;
 
@@ -1336,7 +1465,7 @@ static int cortex_a8_handle_target_request(void *priv)
  * Cortex-A8 target information and configuration
  */
 
-static int cortex_a8_examine(struct target *target)
+static int cortex_a8_examine_first(struct target *target)
 {
        struct cortex_a8_common *cortex_a8 = target_to_cortex_a8(target);
        struct armv7a_common *armv7a = &cortex_a8->armv7a_common;
@@ -1421,10 +1550,21 @@ static int cortex_a8_examine(struct target *target)
        LOG_DEBUG("Configured %i hw breakpoint pairs and %i hw watchpoint pairs",
                        cortex_a8->brp_num , cortex_a8->wrp_num);
 
-       /* Configure core debug access */
-       cortex_a8_init_debug_access(target);
+       target_set_examined(target);
+       return ERROR_OK;
+}
+
+static int cortex_a8_examine(struct target *target)
+{
+       int retval = ERROR_OK;
+
+       /* don't re-probe hardware after each reset */
+       if (!target_was_examined(target))
+               retval = cortex_a8_examine_first(target);
 
-       target->type->examined = 1;
+       /* Configure core debug access */
+       if (retval == ERROR_OK)
+               retval = cortex_a8_init_debug_access(target);
 
        return retval;
 }
@@ -1436,10 +1576,11 @@ static int cortex_a8_examine(struct target *target)
 static void cortex_a8_build_reg_cache(struct target *target)
 {
        struct reg_cache **cache_p = register_get_last_cache_p(&target->reg_cache);
-       struct armv4_5_common_s *armv4_5 = target_to_armv4_5(target);
+       struct arm *armv4_5 = target_to_armv4_5(target);
+
+       armv4_5->core_type = ARM_MODE_MON;
 
        (*cache_p) = armv4_5_build_reg_cache(target, armv4_5);
-       armv4_5->core_cache = (*cache_p);
 }
 
 
@@ -1453,19 +1594,14 @@ static int cortex_a8_init_target(struct command_context *cmd_ctx,
 int cortex_a8_init_arch_info(struct target *target,
                struct cortex_a8_common *cortex_a8, struct jtag_tap *tap)
 {
-       struct arm *armv4_5;
-       struct armv7a_common *armv7a;
-
-       armv7a = &cortex_a8->armv7a_common;
-       armv4_5 = &armv7a->armv4_5_common;
+       struct armv7a_common *armv7a = &cortex_a8->armv7a_common;
+       struct arm *armv4_5 = &armv7a->armv4_5_common;
        struct swjdp_common *swjdp = &armv7a->swjdp_info;
 
        /* Setup struct cortex_a8_common */
        cortex_a8->common_magic = CORTEX_A8_COMMON_MAGIC;
        armv4_5->arch_info = armv7a;
 
-       armv4_5_init_arch_info(target, armv4_5);
-
        /* prepare JTAG information for the new target */
        cortex_a8->jtag_info.tap = tap;
        cortex_a8->jtag_info.scann_size = 4;
@@ -1505,12 +1641,10 @@ LOG_DEBUG(" ");
 
        armv4_5->read_core_reg = cortex_a8_read_core_reg;
        armv4_5->write_core_reg = cortex_a8_write_core_reg;
-//     armv4_5->full_context = arm7_9_full_context;
 
-//     armv4_5->load_core_reg_u32 = cortex_a8_load_core_reg_u32;
-//     armv4_5->store_core_reg_u32 = cortex_a8_store_core_reg_u32;
-//     armv4_5->read_core_reg = armv4_5_read_core_reg; /* this is default */
-//     armv4_5->write_core_reg = armv4_5_write_core_reg;
+       /* REVISIT v7a setup should be in a v7a-specific routine */
+       armv4_5_init_arch_info(target, armv4_5);
+       armv7a->common_magic = ARMV7_COMMON_MAGIC;
 
        target_register_timer_callback(cortex_a8_handle_target_request, 1, 1, target);
 
@@ -1528,17 +1662,17 @@ static int cortex_a8_target_create(struct target *target, Jim_Interp *interp)
 
 COMMAND_HANDLER(cortex_a8_handle_cache_info_command)
 {
-       struct target *target = get_current_target(cmd_ctx);
+       struct target *target = get_current_target(CMD_CTX);
        struct armv7a_common *armv7a = target_to_armv7a(target);
 
-       return armv4_5_handle_cache_info_command(cmd_ctx,
+       return armv4_5_handle_cache_info_command(CMD_CTX,
                        &armv7a->armv4_5_mmu.armv4_5_cache);
 }
 
 
 COMMAND_HANDLER(cortex_a8_handle_dbginit_command)
 {
-       struct target *target = get_current_target(cmd_ctx);
+       struct target *target = get_current_target(CMD_CTX);
 
        cortex_a8_init_debug_access(target);
 
@@ -1590,8 +1724,9 @@ struct target_type cortexa8_target = {
        .read_memory = cortex_a8_read_memory,
        .write_memory = cortex_a8_write_memory,
        .bulk_write_memory = cortex_a8_bulk_write_memory,
-       .checksum_memory = arm7_9_checksum_memory,
-       .blank_check_memory = arm7_9_blank_check_memory,
+
+       .checksum_memory = arm_checksum_memory,
+       .blank_check_memory = arm_blank_check_memory,
 
        .run_algorithm = armv4_5_run_algorithm,