Difference between revisions of "OpenOCD Snowball"

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(While power saving is enabled, the openocd polling is failing because dap is not powered?)
(Known Issues)
Line 18: Line 18:
 
== Known Issues ==
 
== Known Issues ==
  
=====While power saving is enabled, the openocd polling is failing because dap is not powered?=====
+
====While power saving is enabled, the openocd polling is failing because dap is not powered?====
  
 
Apply following patch to openocd and rebuild.
 
Apply following patch to openocd and rebuild.

Revision as of 11:06, 19 April 2012

Introduction

The Snowball is supported on main branch of http://openocd.sourceforge.net.
For using this solution, you need at least:
- a usb jtag dongle,
- an openocd excutable running on linux host machine,
- a gdb cross compile for arm platform.

Eclipse can be used as a GDB front end.

JTAG Hardware HowTos

Following list provides some usb dongle that have tested with snowball :

The openocd application is available in source code. Follow the following step, for building the application.

Known Issues

While power saving is enabled, the openocd polling is failing because dap is not powered?

Apply following patch to openocd and rebuild.

From c3ab72ab20273a54e9f47fce05cedf159847a33d Mon Sep 17 00:00:00 2001
From: Michel Jaouen <michel.jaouen@stericsson.com>
Date: Tue, 26 Jul 2011 11:16:29 +0200
Subject: [PATCH] remove warning when board in sleep

---
 src/target/adi_v5_jtag.c |    8 ++++----
 src/target/cortex_a.c    |    2 +-
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/src/target/adi_v5_jtag.c b/src/target/adi_v5_jtag.c
index 75461c3..eb9627d 100644
--- a/src/target/adi_v5_jtag.c
+++ b/src/target/adi_v5_jtag.c
@@ -296,9 +296,9 @@ static int jtagdp_transaction_endcheck(struct adiv5_dap *dap)
 					dap->ap_csw_value,
 					dap->ap_tar_value);
 
-			if (ctrlstat & SSTICKYORUN)
-				LOG_ERROR("JTAG-DP OVERRUN - check clock, "
-					"memaccess, or reduce jtag speed");
+			//if (ctrlstat & SSTICKYORUN)
+			//	LOG_ERROR("JTAG-DP OVERRUN - check clock, "
+			//		"memaccess, or reduce jtag speed");
 
 			if (ctrlstat & SSTICKYERR)
 				LOG_ERROR("JTAG-DP STICKY ERROR");
@@ -331,7 +331,7 @@ static int jtagdp_transaction_endcheck(struct adiv5_dap *dap)
 
 			if ((retval = dap_run(dap)) != ERROR_OK)
 				return retval;
-			LOG_ERROR("MEM_AP_CSW 0x%" PRIx32 ", MEM_AP_TAR 0x%"
+			LOG_DEBUG("MEM_AP_CSW 0x%" PRIx32 ", MEM_AP_TAR 0x%"
 					PRIx32, mem_ap_csw, mem_ap_tar);
 
 		}
diff --git a/src/target/cortex_a.c b/src/target/cortex_a.c
index 2370d95..1223087 100755
--- a/src/target/cortex_a.c
+++ b/src/target/cortex_a.c
@@ -844,7 +844,7 @@ static int cortex_a8_poll(struct target *target)
 			armv7a->debug_base + CPUDBG_DSCR, &dscr);
 	if (retval != ERROR_OK)
 	{
-		return retval;
+		return ERROR_OK;
 	}
 	cortex_a8->cpudbg_dscr = dscr;
 
-- 
1.7.4.1


Create a file 0001-remove-warning-when-board-in-sleep.patch with patch content.

$git am 0001-remove-warning-when-board-in-sleep.patch
$make


Here is the list of some openocd command for full description, build pdf doc.

$make pdf

A file doc/openocd.pdf is created


"jtag arp_init" : disable all tap from scan chain expect u8500.tapc


"reset" : reset chipset


"scan_chain" : display the element in the scan chain

> scan_chain
   TapName             Enabled  IdCode     Expected   IrLen IrCap IrMask
-- ------------------- -------- ---------- ---------- ----- ----- ------
 0 u8500.dap              Y     0x00000000 0x4ba00477     4 0x0e  0x0f
 1 u8500.jrc              Y     0x52286041 0x*2286041     6 0x06  0x0f


Enabled : "y" means tap is present on scan chain

Irlen : indicates tap len

Ircap : the instruction register address  to use for reading tap ID

Expected : Expected tap id value

Idcode : Tap Id read, at tap insertion.


"targets" : display the status of the targets as shown below

> targets
    TargetName         Type       Endian TapName            State       
--  ------------------ ---------- ------ ------------------ ------------
 0* u8500.cpu1         cortex_a8  little u8500.dap          running
 1  u8500.cpu2         cortex_a8  little u8500.dap          running

"*" indicates the current target


"targets u8500.cpu2" : change current target to u8500.cpu2

> targets u8500.cpu2
> targets
    TargetName         Type       Endian TapName            State       
--  ------------------ ---------- ------ ------------------ ------------
 0  u8500.cpu1         cortex_a8  little u8500.dap          running
 1* u8500.cpu2         cortex_a8  little u8500.dap          running

"poll" : display wether the regulary targets polling is activated or not.


"poll on": launch regulary targets polling.


"poll off": stop regular target polling, in this state , the status displayed by command "targets" is no more reflecting the real target status.


"halt" : request a halt of current target.

"resume" : resume current target (targets reaches "running" status).


"reg" : display all register of current target.

"reg pc" display PC register of current target.

"reg r1 0x3" set r1 register to 0x3 of current target.


"bp" : list the breakpoint hw of current target.


"bp 0x0 4 hw" : set on current target an hw breakpoint on 0x0.

"rpb 0x0" : remove on current target the breakpoint on 0x0.


"mdb 0xC0000000 4" dump 4 bytes of memory at address 0xc0000000. (virtual address if mmu on)

"mwb 0xc00000000 4" write 4 in memory address 0xc0000000.

In ST-Ericsson OpenOCD Cortex A9 implementation, target need to be halted, access is done the cp14 of selected target.


"mdb phys 0x0 4" dump 4 bytes of memory at address 0x000000. (physical address)

> mdb phys 0 4
Wait flushing data l1 on core 1
Wait flushing data l1 on core 0
0x00000000: 03 20 c2 c0 
> 

"shutdown" : kill openocd daemon.



For debugging uboot or linux, you need to build gdb. Download the gdb-7.3a.tar.gz at following address.
http://ftp.gnu.org/gnu/gdb/
Create a specific directory for this gdb built.(later on, we apply a patch for smp full support)

gunzip gdb-7.3a.tar.gz 
tar xvf gdb-7.3.tar
cd gdb-7.3
git init
git add *
git commit -m gdb-7.3a
./configure --target=arm-none-linux-gnueabi
make all
cd ./gdb
./gdb
GNU gdb (GDB) 7.3
Copyright (C) 2011 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
and "show warranty" for details.
This GDB was configured as "--host=x86_64-unknown-linux-gnu --target=arm-none-linux-gnueabi".
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>.

Apply the following patch for smp support.

From 3c35988a8dd4e6c1a18b7156bc1367258e9e2fb9 Mon Sep 17 00:00:00 2001
From: Michel Jaouen <michel.jaouen@stericsson.com>
Date: Fri, 30 Sep 2011 14:45:21 +0200
Subject: [PATCH] OpenOCD : add smp remote protocol message

---
 gdb/remote.c |   71 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
 1 files changed, 70 insertions(+), 1 deletions(-)

diff --git a/gdb/remote.c b/gdb/remote.c
index 243bdd7..7ce402e 100644
--- a/gdb/remote.c
+++ b/gdb/remote.c
@@ -10552,6 +10552,72 @@ remote_upload_trace_state_variables (struct uploaded_tsv **utsvp)
     }
   return 0;
 }
+#define OPENOCD_SMP
+#ifdef OPENOCD_SMP
+static int dummy = 0;
+static int get_core(void)
+{
+	struct remote_state *rs = get_remote_state ();
+	int core = -1;
+	if (!remote_desc)
+    error (_("command can only be used with remote target"));
+	if (remote_desc)
+	{
+		//puts_filtered("sending jc\n");
+		putpkt("jc");
+		//puts_filtered("Jc sent\n");
+		getpkt(&rs->buf, &rs->buf_size, 0);
+		//		print_packet (rs->buf);
+		hex2bin(rs->buf,(gdb_byte *)&core,4);
+	}
+	else return dummy;
+	return core;
+}
+
+static int set_core(int core)
+{
+	char tmp[16];
+	struct remote_state *rs = get_remote_state ();
+	dummy = core;
+	if (!remote_desc)
+    error (_("command can only be used with remote target"));
+	else	{
+		sprintf(tmp,"Jc%x",core);
+		//puts_filtered(tmp);
+		putpkt(tmp);
+		getpkt (&rs->buf, &rs->buf_size, 0);
+	}
+	return 0;
+}
+
+static void smp_value_read (struct value *v)
+{
+	int core = get_core();
+	memcpy (value_contents_all_raw (v),
+			&core,
+			4);
+}
+
+static void smp_value_write (struct value *v, struct value * from)
+{
+	int core;
+	memcpy (&core,value_contents_all_raw (from), 4);
+	set_core(core);
+}
+
+static struct lval_funcs smp_value_funcs = { smp_value_read, smp_value_write };
+
+
+
+static struct value *smp_make_value (struct gdbarch *gdbarch,
+		struct internalvar *var)
+{
+	struct type *type = arch_integer_type (gdbarch, 32, 1, "DWORD32");
+    return allocate_computed_value (type, &smp_value_funcs, NULL);
+}
+#endif
+
+
 
 void
 _initialize_remote (void)
@@ -10559,7 +10625,10 @@ _initialize_remote (void)
   struct remote_state *rs;
   struct cmd_list_element *cmd;
   char *cmd_name;
-
+  /* smp specific  */
+#ifdef OPENOCD_SMP
+  create_internalvar_type_lazy ("_core", smp_make_value);
+#endif
   /* architecture specific data */
   remote_gdbarch_data_handle =
     gdbarch_data_register_post_init (init_remote_state);
-- 
1.7.4.1