fix(errata): workaround for Cortex-A78C erratum 2395411

Cortex-A78C erratum 2395411 is a Cat B erratum that affects
revisions r0p1 and r0p2, and is currently open. The workaround
is to set CPUACTLR2_EL1[40] to 1, which will disable folding
of demand requests into older prefetches with L2 miss requests
outstanding.

SDEN can be found here:
https://developer.arm.com/documentation/SDEN2004089/latest

Signed-off-by: Akram Ahmad <Akram.Ahmad@arm.com>
Change-Id: I4f0fb278ac20a2eb4dd7e4efd1b1246dd85e48c4
diff --git a/docs/design/cpu-specific-build-macros.rst b/docs/design/cpu-specific-build-macros.rst
index 2ddccac..8e4e240 100644
--- a/docs/design/cpu-specific-build-macros.rst
+++ b/docs/design/cpu-specific-build-macros.rst
@@ -335,6 +335,10 @@
   Cortex-A78C CPU. This needs to be enabled for revisions r0p1, r0p2 and
   it is still open.
 
+- ``ERRATA_A78C_2395411`` : This applies errata 2395411 workaround to
+  Cortex-A78C CPU. This needs to be enabled for revisions r0p1 and r0p2. This
+  erratum is still open.
+
 For Cortex-X1 CPU, the following errata build flags are defined:
 
 - ``ERRATA_X1_1821534`` : This applies errata 1821534 workaround to Cortex-X1
diff --git a/include/lib/cpus/aarch64/cortex_a78c.h b/include/lib/cpus/aarch64/cortex_a78c.h
index 54c95ad..7f7b9a5 100644
--- a/include/lib/cpus/aarch64/cortex_a78c.h
+++ b/include/lib/cpus/aarch64/cortex_a78c.h
@@ -14,11 +14,17 @@
 #define CORTEX_A78C_BHB_LOOP_COUNT			U(32)
 
 /*******************************************************************************
+ * CPU Auxiliary Control register 2 specific definitions.
+ * ****************************************************************************/
+#define CORTEX_A78C_CPUACTLR2_EL1			S3_0_C15_C1_1
+#define CORTEX_A78C_CPUACTLR2_EL1_BIT_40 		(ULL(1) << 40)
+
+/*******************************************************************************
  * CPU Extended Control register specific definitions.
  ******************************************************************************/
 #define CORTEX_A78C_CPUECTLR_EL1		        S3_0_C15_C1_4
-#define CORTEX_A78C_CPUECTLR_EL1_BIT6		        (ULL(1) << 6)
-#define CORTEX_A78C_CPUECTLR_EL1_BIT7		        (ULL(1) << 7)
+#define CORTEX_A78C_CPUECTLR_EL1_BIT_6		        (ULL(1) << 6)
+#define CORTEX_A78C_CPUECTLR_EL1_BIT_7		        (ULL(1) << 7)
 
 /*******************************************************************************
  * CPU Power Control register specific definitions
diff --git a/lib/cpus/aarch64/cortex_a78c.S b/lib/cpus/aarch64/cortex_a78c.S
index fc002e9..4f0bb49 100644
--- a/lib/cpus/aarch64/cortex_a78c.S
+++ b/lib/cpus/aarch64/cortex_a78c.S
@@ -17,6 +17,36 @@
 #error "cortex_a78c must be compiled with HW_ASSISTED_COHERENCY enabled"
 #endif
 
+/* --------------------------------------------------
+ * Errata Workaround for Cortex A78C Erratum 2395411.
+ * This applies to revision r0p1 and r0p2 of the A78C
+ * and is currently open. It is a Cat B erratum.
+ * Inputs:
+ * x0: variant[4:7] and revision[0:3] of current cpu.
+ * Shall clobber: x0-x4, x17
+ * --------------------------------------------------
+ */
+func errata_a78c_2395411_wa
+	/* Check revision. */
+	mov 	x17, x30
+	bl 	check_errata_2395411
+	cbz 	x0, 1f
+
+	/* Set CPUACTRL2_EL1[40] to 1. */
+	mrs 	x1, CORTEX_A78C_CPUACTLR2_EL1
+	orr 	x1, x1, #CORTEX_A78C_CPUACTLR2_EL1_BIT_40
+	msr 	CORTEX_A78C_CPUACTLR2_EL1, x1
+1:
+	ret 	x17
+endfunc errata_a78c_2395411_wa
+
+func check_errata_2395411
+	/* Applies to r0p1 and r0p2 */
+	mov 	x1, #0x01
+	mov 	x2, #0x02
+	b 	cpu_rev_var_range
+endfunc check_errata_2395411
+
 #if WORKAROUND_CVE_2022_23960
 	wa_cve_2022_23960_bhb_vector_table CORTEX_A78C_BHB_LOOP_COUNT, cortex_a78c
 #endif /* WORKAROUND_CVE_2022_23960 */
@@ -43,8 +73,8 @@
 	 * --------------------------------------------------------
 	 */
 	mrs	x0, CORTEX_A78C_CPUECTLR_EL1
-	orr	x0, x0, #CORTEX_A78C_CPUECTLR_EL1_BIT6
-	orr	x0, x0, #CORTEX_A78C_CPUECTLR_EL1_BIT7
+	orr	x0, x0, #CORTEX_A78C_CPUECTLR_EL1_BIT_6
+	orr	x0, x0, #CORTEX_A78C_CPUECTLR_EL1_BIT_7
 	msr	CORTEX_A78C_CPUECTLR_EL1, x0
 	isb
 1:
@@ -121,6 +151,11 @@
 	bl	errata_a78c_2242638_wa
 #endif
 
+#if ERRATA_A78C_2395411
+	mov 	x0, x18
+	bl	errata_a78c_2395411_wa
+#endif
+
 #if IMAGE_BL31 && WORKAROUND_CVE_2022_23960
 	/*
 	 * The Cortex-A78c generic vectors are overridden to apply errata
@@ -166,6 +201,7 @@
 	 */
 	report_errata ERRATA_A78C_2132064, cortex_a78c, 2132064
 	report_errata ERRATA_A78C_2242638, cortex_a78c, 2242638
+	report_errata ERRATA_A78C_2395411, cortex_a78c, 2395411
 	report_errata WORKAROUND_CVE_2022_23960, cortex_a78c, cve_2022_23960
 
 	ldp	x8, x30, [sp], #16
diff --git a/lib/cpus/cpu-ops.mk b/lib/cpus/cpu-ops.mk
index b114824..088e885 100644
--- a/lib/cpus/cpu-ops.mk
+++ b/lib/cpus/cpu-ops.mk
@@ -369,6 +369,10 @@
 # to revisions r0p1 and r0p2 of the A78C cpu. It is still open.
 ERRATA_A78C_2242638	?=0
 
+# Flag to apply erratum 2395411 workaround during reset. This erratum applies
+# to revisions r0p1 and r0p2 of the A78C cpu. It is still open.
+ERRATA_A78C_2395411 	?=0
+
 # Flag to apply erratum 1821534 workaround during reset. This erratum applies
 # to revisions r0p0 - r1p0 of the X1 cpu and fixed in r1p1.
 ERRATA_X1_1821534	?=0
@@ -939,6 +943,10 @@
 $(eval $(call assert_boolean,ERRATA_A78C_2242638))
 $(eval $(call add_define,ERRATA_A78C_2242638))
 
+# Process ERRATA_A78C_2395411 flag
+$(eval $(call assert_boolean,ERRATA_A78C_2395411))
+$(eval $(call add_define,ERRATA_A78C_2395411))
+
 # Process ERRATA_X1_1821534 flag
 $(eval $(call assert_boolean,ERRATA_X1_1821534))
 $(eval $(call add_define,ERRATA_X1_1821534))