xscale: always reload handler after reset

Remove needless debug handler state.

 - "handler_installed" became wrong as soon as the second TRST+SRST
   reset was issued ... so the handler was never reloaded after the
   reset removed it from the mini-icache.

   This fixes the bug where subsequent resets fail on PXA255 (if the
   first one even worked, which is uncommon).  Other XScale chips
   would have problems too; PXA270 seems to have, IXP425 maybe not.

 - "handler_running" was never tested; it's pointless.

Plus a related bugfix: invalidate OpenOCD's ARM register cache on reset.
It was no more valid than the XScale's mini-icache.  (Though ... such
invalidations might be better done in "SRST asserted" callbacks.)

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>

diff --git a/src/target/xscale.c b/src/target/xscale.c
index 640eb01b6712531ff41f5851cf4c8b4077a112bb..ee9d88d6463f14b3aed92e74fe49ae6e4e13e8aa 100644 (file)
--- a/src/target/xscale.c
+++ b/src/target/xscale.c
@@ -890,8 +890,6 @@ static int xscale_arch_state(struct target_s *target)
 static int xscale_poll(target_t *target)
 {
        int retval = ERROR_OK;
 static int xscale_poll(target_t *target)
 {
        int retval = ERROR_OK;

-       armv4_5_common_t *armv4_5 = target->arch_info;
-       xscale_common_t *xscale = armv4_5->arch_info;

 
        if ((target->state == TARGET_RUNNING) || (target->state == TARGET_DEBUG_RUNNING))
        {
 
        if ((target->state == TARGET_RUNNING) || (target->state == TARGET_DEBUG_RUNNING))
        {


@@ -900,8 +898,6 @@ static int xscale_poll(target_t *target)
                {
 
                        /* there's data to read from the tx register, we entered debug state */
                {
 
                        /* there's data to read from the tx register, we entered debug state */

-                       xscale->handler_running = 1;
-

                        target->state = TARGET_HALTED;
 
                        /* process debug entry, fetching current mode regs */
                        target->state = TARGET_HALTED;
 
                        /* process debug entry, fetching current mode regs */


@@ -1365,8 +1361,6 @@ static int xscale_resume(struct target_s *target, int current,
 
        LOG_DEBUG("target resumed");
 
 
        LOG_DEBUG("target resumed");
 

-       xscale->handler_running = 1;
-

        return ERROR_OK;
 }
 
        return ERROR_OK;
 }
 


@@ -1574,7 +1568,17 @@ static int xscale_deassert_reset(target_t *target)
                breakpoint = breakpoint->next;
        }
 
                breakpoint = breakpoint->next;
        }
 

-       if (!xscale->handler_installed)
+       armv4_5_invalidate_core_regs(target);
+
+       /* FIXME mark hardware watchpoints got unset too.  Also,
+        * at least some of the XScale registers are invalid...
+        */
+
+       /*
+        * REVISIT:  *assumes* we had a SRST+TRST reset so the mini-icache
+        * contents got invalidated.  Safer to force that, so writing new
+        * contents can't ever fail..
+        */

        {
                uint32_t address;
                unsigned buf_cnt;
        {
                uint32_t address;
                unsigned buf_cnt;


@@ -1599,10 +1603,6 @@ static int xscale_deassert_reset(target_t *target)
                 * it's using halt mode (not monitor mode), it runs in
                 * "Special Debug State" for access to registers, memory,
                 * coprocessors, trace data, etc.
                 * it's using halt mode (not monitor mode), it runs in
                 * "Special Debug State" for access to registers, memory,
                 * coprocessors, trace data, etc.

-                *
-                * REVISIT:  *assumes* we've had a SRST+TRST reset so the
-                * mini-icache contents have been invalidated.  Safest to
-                * force that, so writing new contents is reliable...

                 */
                address = xscale->handler_address;
                for (unsigned binary_size = sizeof xscale_debug_handler - 1;
                 */
                address = xscale->handler_address;
                for (unsigned binary_size = sizeof xscale_debug_handler - 1;


@@ -1673,10 +1673,6 @@ static int xscale_deassert_reset(target_t *target)
                        xscale_resume(target, 1, 0x0, 1, 0);
                }
        }
                        xscale_resume(target, 1, 0x0, 1, 0);
                }
        }

-       else
-       {
-               jtag_add_reset(0, 0);
-       }

 
        return ERROR_OK;
 }
 
        return ERROR_OK;
 }


@@ -2967,8 +2963,6 @@ static int xscale_init_arch_info(target_t *target,
        }
 
        /* the debug handler isn't installed (and thus not running) at this time */
        }
 
        /* the debug handler isn't installed (and thus not running) at this time */

-       xscale->handler_installed = 0;
-       xscale->handler_running = 0;

        xscale->handler_address = 0xfe000800;
 
        /* clear the vectors we keep locally for reference */
        xscale->handler_address = 0xfe000800;
 
        /* clear the vectors we keep locally for reference */

diff --git a/src/target/xscale.h b/src/target/xscale.h
index a5d83ee675c7a4aafe3385ac3ff1d08d1497e8d9..4b34cf88b72ebf5506a11a7ac39e145ba915c6e8 100644 (file)
--- a/src/target/xscale.h
+++ b/src/target/xscale.h
@@ -86,8 +86,6 @@ typedef struct xscale_common_s
        reg_cache_t *reg_cache;
 
        /* current state of the debug handler */
        reg_cache_t *reg_cache;
 
        /* current state of the debug handler */

-       int handler_installed;
-       int handler_running;

        uint32_t handler_address;
 
        /* target-endian buffers with exception vectors */
        uint32_t handler_address;
 
        /* target-endian buffers with exception vectors */