Merge commit 'c0053bd50af5' into omap-for-v4.8/soc

3 files changed, 52 insertions, 5 deletions

diff --git a/arch/arm/mach-omap2/Kconfig b/arch/arm/mach-omap2/Kconfig
index 0517f0c..a63d3fe 100644
--- a/arch/arm/mach-omap2/Kconfig
+++ b/arch/arm/mach-omap2/Kconfig
@@ -240,4 +240,12 @@ endmenu
 
 endif
 
+config OMAP5_ERRATA_801819
+	bool "Errata 801819: An eviction from L1 data cache might stall indefinitely"
+	depends on SOC_OMAP5 || SOC_DRA7XX
+	help
+	  A livelock can occur in the L2 cache arbitration that might prevent
+	  a snoop from completing. Under certain conditions this can cause the
+	  system to deadlock.
+
 endmenu
diff --git a/arch/arm/mach-omap2/omap-secure.h b/arch/arm/mach-omap2/omap-secure.h
index af2851f..bae263f 100644
--- a/arch/arm/mach-omap2/omap-secure.h
+++ b/arch/arm/mach-omap2/omap-secure.h
@@ -46,6 +46,7 @@
 
 #define OMAP5_DRA7_MON_SET_CNTFRQ_INDEX	0x109
 #define OMAP5_MON_AMBA_IF_INDEX		0x108
+#define OMAP5_DRA7_MON_SET_ACR_INDEX	0x107
 
 /* Secure PPA(Primary Protected Application) APIs */
 #define OMAP4_PPA_L2_POR_INDEX		0x23
diff --git a/arch/arm/mach-omap2/omap-smp.c b/arch/arm/mach-omap2/omap-smp.c
index c625cc1..8cd1de9 100644
--- a/arch/arm/mach-omap2/omap-smp.c
+++ b/arch/arm/mach-omap2/omap-smp.c
@@ -50,6 +50,39 @@ void __iomem *omap4_get_scu_base(void)
 	return scu_base;
 }
 
+#ifdef CONFIG_OMAP5_ERRATA_801819
+void omap5_erratum_workaround_801819(void)
+{
+	u32 acr, revidr;
+	u32 acr_mask;
+
+	/* REVIDR[3] indicates erratum fix available on silicon */
+	asm volatile ("mrc p15, 0, %0, c0, c0, 6" : "=r" (revidr));
+	if (revidr & (0x1 << 3))
+		return;
+
+	asm volatile ("mrc p15, 0, %0, c1, c0, 1" : "=r" (acr));
+	/*
+	 * BIT(27) - Disables streaming. All write-allocate lines allocate in
+	 * the L1 or L2 cache.
+	 * BIT(25) - Disables streaming. All write-allocate lines allocate in
+	 * the L1 cache.
+	 */
+	acr_mask = (0x3 << 25) | (0x3 << 27);
+	/* do we already have it done.. if yes, skip expensive smc */
+	if ((acr & acr_mask) == acr_mask)
+		return;
+
+	acr |= acr_mask;
+	omap_smc1(OMAP5_DRA7_MON_SET_ACR_INDEX, acr);
+
+	pr_debug("%s: ARM erratum workaround 801819 applied on CPU%d\n",
+		 __func__, smp_processor_id());
+}
+#else
+static inline void omap5_erratum_workaround_801819(void) { }
+#endif
+
 static void omap4_secondary_init(unsigned int cpu)
 {
 	/*
@@ -64,12 +97,15 @@ static void omap4_secondary_init(unsigned int cpu)
 		omap_secure_dispatcher(OMAP4_PPA_CPU_ACTRL_SMP_INDEX,
 							4, 0, 0, 0, 0, 0);
 
-	/*
-	 * Configure the CNTFRQ register for the secondary cpu's which
-	 * indicates the frequency of the cpu local timers.
-	 */
-	if (soc_is_omap54xx() || soc_is_dra7xx())
+	if (soc_is_omap54xx() || soc_is_dra7xx()) {
+		/*
+		 * Configure the CNTFRQ register for the secondary cpu's which
+		 * indicates the frequency of the cpu local timers.
+		 */
 		set_cntfreq();
+		/* Configure ACR to disable streaming WA for 801819 */
+		omap5_erratum_workaround_801819();
+	}
 
 	/*
 	 * Synchronise with the boot thread.
@@ -218,6 +254,8 @@ static void __init omap4_smp_prepare_cpus(unsigned int max_cpus)
 
 	if (cpu_is_omap446x())
 		startup_addr = omap4460_secondary_startup;
+	if (soc_is_dra74x() || soc_is_omap54xx())
+		omap5_erratum_workaround_801819();
 
 	/*
 	 * Write the address of secondary startup routine into the