powerpc/mpc85xx: Workaround for A-005812
Erratum A-005812 Incorrect reservation clearing in Write Shadow mode can
result in invalid atomic operations. For u-boot, this erratum only impacts
SoCs running in write shadow mode.
Signed-off-by: York Sun <yorksun@freescale.com>
diff --git a/arch/powerpc/cpu/mpc85xx/release.S b/arch/powerpc/cpu/mpc85xx/release.S
index 15bbbc1..c15e83b 100644
--- a/arch/powerpc/cpu/mpc85xx/release.S
+++ b/arch/powerpc/cpu/mpc85xx/release.S
@@ -226,6 +226,21 @@
2:
#endif
+#ifdef CONFIG_SYS_FSL_ERRATUM_A005812
+ /*
+ * A-005812 workaround sets bit 32 of SPR 976 for SoCs running in
+ * write shadow mode. This code should run after other code setting
+ * DCWS.
+ */
+ mfspr r3,L1CSR2
+ andis. r3,r3,(L1CSR2_DCWS)@h
+ beq 1f
+ mfspr r3, SPRN_HDBCR0
+ oris r3, r3, 0x8000
+ mtspr SPRN_HDBCR0, r3
+1:
+#endif
+
#ifdef CONFIG_BACKSIDE_L2_CACHE
/* skip L2 setup on P2040/P2040E as they have no L2 */
mfspr r3,SPRN_SVR