Subject: Add a 'sd' command (spu dump) to xmon to dump spu local store

From: Michael Ellerman <michael@ellerman.id.au>
Add a command to xmon to dump the memory of a spu's local store.
This mimics the 'd' command which dumps regular memory, but does
a little hand holding by taking the user supplied address and
finding that offset in the local store for the specified spu.

This makes it easy for example to look at what was executing on a spu:

1:mon> ss
...
Stopped spu 04 (was running)
...
1:mon> sf 4
Dumping spu fields at address c0000000019e0a00:
...
  problem->spu_npc_RW     = 0x228
...
1:mon> sd 4 0x228
d000080080318228 01a00c021cffc408 4020007f217ff488  |........@ ..!...|

Aha, 01a00c02, which is of course rdch $2,$ch24 !

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
---
 arch/powerpc/xmon/xmon.c |   52 ++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 51 insertions(+), 1 deletion(-)

Index: linux-2.6/arch/powerpc/xmon/xmon.c
===================================================================
--- linux-2.6.orig/arch/powerpc/xmon/xmon.c
+++ linux-2.6/arch/powerpc/xmon/xmon.c
@@ -215,7 +215,8 @@ Commands:\n\
 #ifdef CONFIG_PPC_CELL
 "  ss	stop execution on all spus\n\
   sr	restore execution on stopped spus\n\
-  sf #	dump spu fields for spu # (in hex)\n"
+  sf #	dump spu fields for spu # (in hex)\n\
+  sd #	dump spu local store for spu # (in hex)\n"
 #endif
 "  S	print special registers\n\
   t	print backtrace\n\
@@ -2649,6 +2650,7 @@ struct spu_info {
 	struct spu *spu;
 	u64 saved_mfc_sr1_RW;
 	u32 saved_spu_runcntl_RW;
+	unsigned long dump_addr;
 	u8 stopped_ok;
 };
 
@@ -2668,6 +2670,8 @@ void xmon_register_spus(struct list_head
 
 		spu_info[spu->number].spu = spu;
 		spu_info[spu->number].stopped_ok = 0;
+		spu_info[spu->number].dump_addr = (unsigned long)
+				spu_info[spu->number].spu->local_store;
 	}
 }
 
@@ -2813,6 +2817,48 @@ static void dump_spu_fields(struct spu *
 	DUMP_FIELD(spu, "0x%p", priv2);
 }
 
+static void dump_spu_ls(void)
+{
+	static unsigned long num;
+	unsigned long offset, addr, ls_addr;
+	int rc;
+
+	scanhex(&num);
+	if (num >= XMON_NUM_SPUS || !spu_info[num].spu) {
+		printf("*** Error: invalid spu number\n");
+		return;
+	}
+
+	rc = scanhex(&offset);
+
+	if (setjmp(bus_error_jmp) == 0) {
+		catch_memory_errors = 1;
+		sync();
+
+		ls_addr = (unsigned long)spu_info[num].spu->local_store;
+		if (rc)
+			addr = ls_addr + offset;
+		else
+			addr = spu_info[num].dump_addr;
+
+		if (addr < ls_addr + LS_SIZE) {
+			prdump(addr, 64);
+			spu_info[num].dump_addr = addr + 64;
+		} else {
+			printf("*** Error: address outside of local store\n");
+			last_cmd = NULL;
+		}
+
+		sync();
+		__delay(200);
+	} else {
+		catch_memory_errors = 0;
+		printf("*** Error: dumping local store for spu %d\n", num);
+	}
+
+	catch_memory_errors = 0;
+}
+
 static int do_spu_cmd(void)
 {
 	unsigned long num = 0;
@@ -2832,6 +2878,10 @@ static int do_spu_cmd(void)
 		else
 			printf("*** Error: invalid spu number\n");
 		break;
+	case 'd':
+		last_cmd = "sd\n";
+		dump_spu_ls();
+		break;
 	default:
 		return -1;
 	}