summaryrefslogtreecommitdiff
path: root/post/lib_ppc/b.c
diff options
context:
space:
mode:
Diffstat (limited to 'post/lib_ppc/b.c')
-rw-r--r--post/lib_ppc/b.c197
1 files changed, 197 insertions, 0 deletions
diff --git a/post/lib_ppc/b.c b/post/lib_ppc/b.c
new file mode 100644
index 00000000000..b4b17c8ff07
--- /dev/null
+++ b/post/lib_ppc/b.c
@@ -0,0 +1,197 @@
+/*
+ * (C) Copyright 2002
+ * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <common.h>
+
+/*
+ * CPU test
+ * Branch instructions: b, bl, bc
+ *
+ * The first 2 instructions (b, bl) are verified by jumping
+ * to a fixed address and checking whether control was transfered
+ * to that very point. For the bl instruction the value of the
+ * link register is checked as well (using mfspr).
+ * To verify the bc instruction various combinations of the BI/BO
+ * fields, the CTR and the condition register values are
+ * checked. The list of such combinations is pre-built and
+ * linked in U-Boot at build time.
+ */
+
+#ifdef CONFIG_POST
+
+#include <post.h>
+#include "cpu_asm.h"
+
+#if CONFIG_POST & CFG_POST_CPU
+
+extern void cpu_post_exec_11 (ulong *code, ulong *res, ulong op1);
+extern void cpu_post_exec_31 (ulong *code, ulong *ctr, ulong *lr, ulong *jump,
+ ulong cr);
+
+static int cpu_post_test_bc (ulong cmd, ulong bo, ulong bi,
+ int pjump, int dec, int link, ulong pctr, ulong cr)
+{
+ int ret = 0;
+ ulong lr = 0;
+ ulong ctr = pctr;
+ ulong jump;
+
+ unsigned long code[] =
+ {
+ ASM_MTCR(6),
+ ASM_MFLR(6),
+ ASM_MTCTR(3),
+ ASM_MTLR(4),
+ ASM_LI(5, 1),
+ ASM_3O(cmd, bo, bi, 8),
+ ASM_LI(5, 0),
+ ASM_MFCTR(3),
+ ASM_MFLR(4),
+ ASM_MTLR(6),
+ ASM_BLR,
+ };
+
+ cpu_post_exec_31 (code, &ctr, &lr, &jump, cr);
+
+ if (ret == 0)
+ ret = pjump == jump ? 0 : -1;
+ if (ret == 0)
+ {
+ if (dec)
+ ret = pctr == ctr + 1 ? 0 : -1;
+ else
+ ret = pctr == ctr ? 0 : -1;
+ }
+ if (ret == 0)
+ {
+ if (link)
+ ret = lr == (ulong) code + 24 ? 0 : -1;
+ else
+ ret = lr == 0 ? 0 : -1;
+ }
+
+ return ret;
+}
+
+int cpu_post_test_b (void)
+{
+ int ret = 0;
+ unsigned int i;
+
+ if (ret == 0)
+ {
+ ulong code[] =
+ {
+ ASM_MFLR(4),
+ ASM_MTLR(3),
+ ASM_B(4),
+ ASM_MFLR(3),
+ ASM_MTLR(4),
+ ASM_BLR,
+ };
+ ulong res;
+
+ cpu_post_exec_11 (code, &res, 0);
+
+ ret = res == 0 ? 0 : -1;
+
+ if (ret != 0)
+ {
+ post_log ("Error at b1 test !\n");
+ }
+ }
+
+ if (ret == 0)
+ {
+ ulong code[] =
+ {
+ ASM_MFLR(4),
+ ASM_MTLR(3),
+ ASM_BL(4),
+ ASM_MFLR(3),
+ ASM_MTLR(4),
+ ASM_BLR,
+ };
+ ulong res;
+
+ cpu_post_exec_11 (code, &res, 0);
+
+ ret = res == (ulong)code + 12 ? 0 : -1;
+
+ if (ret != 0)
+ {
+ post_log ("Error at b2 test !\n");
+ }
+ }
+
+ if (ret == 0)
+ {
+ ulong cc, cd;
+ int cond;
+ ulong ctr;
+ int link;
+
+ i = 0;
+
+ for (cc = 0; cc < 4 && ret == 0; cc++)
+ {
+ for (cd = 0; cd < 4 && ret == 0; cd++)
+ {
+ for (link = 0; link <= 1 && ret == 0; link++)
+ {
+ for (cond = 0; cond <= 1 && ret == 0; cond++)
+ {
+ for (ctr = 1; ctr <= 2 && ret == 0; ctr++)
+ {
+ int dec = cd < 2;
+ int cr = cond ? 0x80000000 : 0x00000000;
+ int jumpc = cc >= 2 ||
+ (cc == 0 && !cond) ||
+ (cc == 1 && cond);
+ int jumpd = cd >= 2 ||
+ (cd == 0 && ctr != 1) ||
+ (cd == 1 && ctr == 1);
+ int jump = jumpc && jumpd;
+
+ ret = cpu_post_test_bc (link ? OP_BCL : OP_BC,
+ (cc << 3) + (cd << 1), 0, jump, dec, link,
+ ctr, cr);
+
+ if (ret != 0)
+ {
+ post_log ("Error at b3 test %d !\n", i);
+ }
+
+ i++;
+ }
+ }
+ }
+ }
+ }
+ }
+
+ return ret;
+}
+
+#endif
+#endif