From d217a9ad01ee6557a0c47cfc745eef6890507bbb Mon Sep 17 00:00:00 2001
From: York Sun <yorksun@freescale.com>
Date: Tue, 25 Jun 2013 11:37:49 -0700
Subject: [PATCH] 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>
---
arch/powerpc/cpu/mpc85xx/cmd_errata.c | 3 +++
arch/powerpc/cpu/mpc85xx/cpu_init.c | 8 ++++++++
arch/powerpc/cpu/mpc85xx/release.S | 15 +++++++++++++++
arch/powerpc/include/asm/config_mpc85xx.h | 3 +++
4 files changed, 29 insertions(+)
diff --git a/arch/powerpc/cpu/mpc85xx/cmd_errata.c b/arch/powerpc/cpu/mpc85xx/cmd_errata.c
index 5cd02ccde6..cbb443fd2c 100644
--- a/arch/powerpc/cpu/mpc85xx/cmd_errata.c
+++ b/arch/powerpc/cpu/mpc85xx/cmd_errata.c
@@ -244,6 +244,9 @@ static int do_errata(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
#endif
#ifdef CONFIG_SYS_FSL_ERRATUM_A006593
puts("Work-around for Erratum A006593 enabled\n");
+#endif
+#ifdef CONFIG_SYS_FSL_ERRATUM_A005812
+ puts("Work-around for Erratum A-005812 enabled\n");
#endif
return 0;
}
diff --git a/arch/powerpc/cpu/mpc85xx/cpu_init.c b/arch/powerpc/cpu/mpc85xx/cpu_init.c
index 1774462a42..48b38263fd 100644
--- a/arch/powerpc/cpu/mpc85xx/cpu_init.c
+++ b/arch/powerpc/cpu/mpc85xx/cpu_init.c
@@ -399,6 +399,14 @@ int cpu_init_r(void)
sync();
}
#endif
+#ifdef CONFIG_SYS_FSL_ERRATUM_A005812
+ /*
+ * A-005812 workaround sets bit 32 of SPR 976 for SoCs running
+ * in write shadow mode. Checking DCWS before setting SPR 976.
+ */
+ if (mfspr(L1CSR2) & L1CSR2_DCWS)
+ mtspr(SPRN_HDBCR0, (mfspr(SPRN_HDBCR0) | 0x80000000));
+#endif
#if defined(CONFIG_PPC_SPINTABLE_COMPATIBLE) && defined(CONFIG_MP)
spin = getenv("spin_table_compat");
diff --git a/arch/powerpc/cpu/mpc85xx/release.S b/arch/powerpc/cpu/mpc85xx/release.S
index 15bbbc15aa..c15e83b521 100644
--- a/arch/powerpc/cpu/mpc85xx/release.S
+++ b/arch/powerpc/cpu/mpc85xx/release.S
@@ -226,6 +226,21 @@ __secondary_start_page:
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
diff --git a/arch/powerpc/include/asm/config_mpc85xx.h b/arch/powerpc/include/asm/config_mpc85xx.h
index c3a37600d3..91fda7ea41 100644
--- a/arch/powerpc/include/asm/config_mpc85xx.h
+++ b/arch/powerpc/include/asm/config_mpc85xx.h
@@ -368,6 +368,7 @@
#define CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY 0xf0000000
#define CONFIG_SYS_FSL_ERRATUM_SRIO_A004034
#define CONFIG_SYS_FSL_ERRATUM_A004849
+#define CONFIG_SYS_FSL_ERRATUM_A005812
#elif defined(CONFIG_PPC_P4080) /* also supports P4040 */
#define CONFIG_SYS_FSL_QORIQ_CHASSIS1
@@ -413,6 +414,7 @@
#define CONFIG_SYS_FSL_ERRATUM_A004849
#define CONFIG_SYS_FSL_ERRATUM_A004580
#define CONFIG_SYS_P4080_ERRATUM_PCIE_A003
+#define CONFIG_SYS_FSL_ERRATUM_A005812
#elif defined(CONFIG_PPC_P5020) /* also supports P5010 */
#define CONFIG_SYS_PPC64 /* 64-bit core */
@@ -474,6 +476,7 @@
#define CONFIG_SYS_FSL_ERRATUM_A004510
#define CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV 0x10
#define CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY 0xf0000000
+#define CONFIG_SYS_FSL_ERRATUM_A005812
#elif defined(CONFIG_BSC9131)
#define CONFIG_MAX_CPUS 1
--
2.39.5