Merge "Neoverse N1 Errata Workaround 1542419" into integration

3 files changed, 113 insertions, 1 deletions

diff --git a/lib/cpus/aarch64/cpu_helpers.S b/lib/cpus/aarch64/cpu_helpers.S
index de1177c3..808c7f80 100644
--- a/lib/cpus/aarch64/cpu_helpers.S
+++ b/lib/cpus/aarch64/cpu_helpers.S
@@ -227,6 +227,27 @@ func cpu_rev_var_hs
 	ret
 endfunc cpu_rev_var_hs
 
+/*
+ * Compare the CPU's revision-variant (x0) with a given range (x1 - x2), for errata
+ * application purposes. If the revision-variant is between or includes the given
+ * values, this indicates that errata applies; otherwise not.
+ *
+ * Shall clobber: x0-x4
+ */
+	.globl	cpu_rev_var_range
+func cpu_rev_var_range
+	mov	x3, #ERRATA_APPLIES
+	mov	x4, #ERRATA_NOT_APPLIES
+	cmp	x0, x1
+	csel	x1, x3, x4, hs
+	cbz	x1, 1f
+	cmp	x0, x2
+	csel	x1, x3, x4, ls
+1:
+	mov	x0, x1
+	ret
+endfunc cpu_rev_var_range
+
 #if REPORT_ERRATA
 /*
  * void print_errata_status(void);
diff --git a/lib/cpus/aarch64/neoverse_n1.S b/lib/cpus/aarch64/neoverse_n1.S
index 31e7a3a7..c9bb005e 100644
--- a/lib/cpus/aarch64/neoverse_n1.S
+++ b/lib/cpus/aarch64/neoverse_n1.S
@@ -9,6 +9,7 @@
 #include <neoverse_n1.h>
 #include <cpuamu.h>
 #include <cpu_macros.S>
+#include <context.h>
 
 /* Hardware handled coherency */
 #if HW_ASSISTED_COHERENCY == 0
@@ -20,6 +21,10 @@
 #error "Neoverse-N1 supports only AArch64. Compile with CTX_INCLUDE_AARCH32_REGS=0"
 #endif
 
+#if ERRATA_N1_IC_TRAP
+	.global neoverse_n1_errata_ic_trap_handler
+#endif
+
 /* --------------------------------------------------
  * Errata Workaround for Neoverse N1 Erratum 1043202.
  * This applies to revision r0p0 and r1p0 of Neoverse N1.
@@ -337,6 +342,41 @@ func check_errata_1315703
 	b	cpu_rev_var_ls
 endfunc check_errata_1315703
 
+/* --------------------------------------------------
+ * Errata Workaround for Neoverse N1 Erratum 1542419.
+ * This applies to revisions r3p0 - r4p0 of Neoverse N1
+ * Inputs:
+ * x0: variant[4:7] and revision[0:3] of current cpu.
+ * Shall clobber: x0-x17
+ * --------------------------------------------------
+ */
+func errata_n1_1542419_wa
+	/* Compare x0 against revision r3p0 and r4p0 */
+	mov	x17, x30
+	bl	check_errata_1542419
+	cbz	x0, 1f
+
+        /* Apply instruction patching sequence */
+	ldr	x0, =0x0
+	msr	CPUPSELR_EL3, x0
+	ldr	x0, =0xEE670D35
+	msr	CPUPOR_EL3, x0
+	ldr	x0, =0xFFFF0FFF
+	msr	CPUPMR_EL3, x0
+	ldr	x0, =0x08000020007D
+	msr	CPUPCR_EL3, x0
+	isb
+1:
+	ret	x17
+endfunc errata_n1_1542419_wa
+
+func check_errata_1542419
+	/* Applies to everything r3p0 - r4p0. */
+	mov	x1, #0x30
+	mov	x2, #0x40
+	b	cpu_rev_var_range
+endfunc check_errata_1542419
+
 func neoverse_n1_reset_func
 	mov	x19, x30
 
@@ -406,6 +446,11 @@ func neoverse_n1_reset_func
 	bl	errata_n1_1315703_wa
 #endif
 
+#if ERRATA_N1_1542419
+	mov	x0, x18
+	bl	errata_n1_1542419_wa
+#endif
+
 #if ENABLE_AMU
 	/* Make sure accesses from EL0/EL1 and EL2 are not trapped to EL3 */
 	mrs	x0, actlr_el3
@@ -471,6 +516,7 @@ func neoverse_n1_errata_report
 	report_errata ERRATA_N1_1262888, neoverse_n1, 1262888
 	report_errata ERRATA_N1_1275112, neoverse_n1, 1275112
 	report_errata ERRATA_N1_1315703, neoverse_n1, 1315703
+	report_errata ERRATA_N1_1542419, neoverse_n1, 1542419
 	report_errata ERRATA_DSU_936184, neoverse_n1, dsu_936184
 
 	ldp	x8, x30, [sp], #16
@@ -478,6 +524,42 @@ func neoverse_n1_errata_report
 endfunc neoverse_n1_errata_report
 #endif
 
+/*
+ * Handle trap of EL0 IC IVAU instructions to EL3 by executing a TLB
+ * inner-shareable invalidation to an arbitrary address followed by a DSB.
+ *
+ * x1: Exception Syndrome
+ */
+func neoverse_n1_errata_ic_trap_handler
+	cmp	x1, #NEOVERSE_N1_EC_IC_TRAP
+	b.ne	1f
+	tlbi	vae3is, xzr
+	dsb	sy
+
+        # Skip the IC instruction itself
+        mrs     x3, elr_el3
+        add     x3, x3, #4
+        msr     elr_el3, x3
+
+	ldp	x0, x1, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X0]
+	ldp	x2, x3, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X2]
+	ldp	x4, x5, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X4]
+	ldr	x30, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_LR]
+
+#if IMAGE_BL31 && RAS_EXTENSION
+	/*
+	 * Issue Error Synchronization Barrier to synchronize SErrors before
+	 * exiting EL3. We're running with EAs unmasked, so any synchronized
+	 * errors would be taken immediately; therefore no need to inspect
+	 * DISR_EL1 register.
+	 */
+	esb
+#endif
+	eret
+1:
+	ret
+endfunc neoverse_n1_errata_ic_trap_handler
+
 	/* ---------------------------------------------
 	 * This function provides neoverse_n1 specific
 	 * register information for crash reporting.
@@ -497,6 +579,7 @@ func neoverse_n1_cpu_reg_dump
 	ret
 endfunc neoverse_n1_cpu_reg_dump
 
-declare_cpu_ops neoverse_n1, NEOVERSE_N1_MIDR, \
+declare_cpu_ops_eh neoverse_n1, NEOVERSE_N1_MIDR, \
 	neoverse_n1_reset_func, \
+	neoverse_n1_errata_ic_trap_handler, \
 	neoverse_n1_core_pwr_dwn
diff --git a/lib/cpus/cpu-ops.mk b/lib/cpus/cpu-ops.mk
index 26040235..078888eb 100644
--- a/lib/cpus/cpu-ops.mk
+++ b/lib/cpus/cpu-ops.mk
@@ -278,6 +278,10 @@ ERRATA_N1_1275112	?=0
 # to revisions before r3p1 of the Neoverse N1 cpu.
 ERRATA_N1_1315703	?=1
 
+# Flag to apply erratum 1542419 workaround during reset. This erratum applies
+# to revisions r3p0 - r4p0 of the Neoverse N1 cpu.
+ERRATA_N1_1542419	?=0
+
 # Flag to apply DSU erratum 798953. This erratum applies to DSUs revision r0p0.
 # Applying the workaround results in higher DSU power consumption on idle.
 ERRATA_DSU_798953	?=0
@@ -507,6 +511,10 @@ $(eval $(call add_define,ERRATA_N1_1275112))
 $(eval $(call assert_boolean,ERRATA_N1_1315703))
 $(eval $(call add_define,ERRATA_N1_1315703))
 
+# Process ERRATA_N1_1542419 flag
+$(eval $(call assert_boolean,ERRATA_N1_1542419))
+$(eval $(call add_define,ERRATA_N1_1542419))
+
 # Process ERRATA_DSU_798953 flag
 $(eval $(call assert_boolean,ERRATA_DSU_798953))
 $(eval $(call add_define,ERRATA_DSU_798953))