fix(errata): workaround for Cortex-A510 erratum 1922240

Cortex-A510 erratum 1922240 is a Cat B erratum that applies to revision
r0p0 and is fixed in r0p1.

Since no errata framework code existed for A510 prior to this patch, it
has been added as well. Also some general cleanup changes in the CPU lib
makefile.

SDEN can be found here:
https://developer.arm.com/documentation/SDEN2397239

Signed-off-by: John Powell <john.powell@arm.com>
Change-Id: I8c427ef255cb4b38ed3e5c2c7444fcef957277e4

docs/design/cpu-specific-build-macros.rst

@@ -474,6 +474,12 @@ For Cortex-X2, the following errata build flags are defined :
    Cortex-X2 CPU. This needs to be enabled only for revisions r0p0, r1p0 and
    r2p0 of the CPU, it is fixed in r2p1.
 
+For Cortex-A510, the following errata build flags are defined :
+
+-  ``ERRATA_A510_1922240``: This applies errata 1922240 workaround to
+   Cortex-A510 CPU. This needs to be enabled only for revision r0p0, it is
+   fixed in r0p1.
+
 DSU Errata Workarounds
 ----------------------
 

include/lib/cpus/aarch64/cortex_a510.h

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2021, ARM Limited. All rights reserved.
+ * Copyright (c) 2022, ARM Limited. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -20,4 +20,9 @@
 #define CORTEX_A510_CPUPWRCTLR_EL1				S3_0_C15_C2_7
 #define CORTEX_A510_CPUPWRCTLR_EL1_CORE_PWRDN_BIT		U(1)
 
+/*******************************************************************************
+ * Complex auxiliary control register specific definitions
+ ******************************************************************************/
+#define CORTEX_A510_CMPXACTLR_EL1				S3_0_C15_C1_3
+
 #endif /* CORTEX_A510_H */

lib/cpus/aarch64/cortex_a510.S

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2021, ARM Limited. All rights reserved.
+ * Copyright (c) 2022, ARM Limited. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -13,14 +13,43 @@
 
 /* Hardware handled coherency */
 #if HW_ASSISTED_COHERENCY == 0
-#error "Cortex A510 must be compiled with HW_ASSISTED_COHERENCY enabled"
+#error "Cortex-A510 must be compiled with HW_ASSISTED_COHERENCY enabled"
 #endif
 
 /* 64-bit only core */
 #if CTX_INCLUDE_AARCH32_REGS == 1
-#error "Cortex A510 supports only AArch64. Compile with CTX_INCLUDE_AARCH32_REGS=0"
+#error "Cortex-A510 supports only AArch64. Compile with CTX_INCLUDE_AARCH32_REGS=0"
 #endif
 
+	/* --------------------------------------------------
+	 * Errata Workaround for Cortex-A510 Errata #1922240.
+	 * This applies only to revision r0p0 (fixed in r0p1)
+	 * x0: variant[4:7] and revision[0:3] of current cpu.
+	 * Shall clobber: x0, x1, x17
+	 * --------------------------------------------------
+	 */
+func errata_cortex_a510_1922240_wa
+	/* Check workaround compatibility. */
+	mov	x17, x30
+	bl	check_errata_1922240
+	cbz	x0, 1f
+
+	/* Apply the workaround by setting IMP_CMPXACTLR_EL1[11:10] = 0b11. */
+	mrs	x0, CORTEX_A510_CMPXACTLR_EL1
+	mov	x1, #3
+	bfi	x0, x1, #10, #2
+	msr	CORTEX_A510_CMPXACTLR_EL1, x0
+
+1:
+	ret	x17
+endfunc errata_cortex_a510_1922240_wa
+
+func check_errata_1922240
+	/* Applies to r0p0 only */
+	mov	x1, #0x00
+	b	cpu_rev_var_ls
+endfunc check_errata_1922240
+
 	/* ----------------------------------------------------
 	 * HW will do the cache maintenance while powering down
 	 * ----------------------------------------------------
@@ -38,19 +67,43 @@ func cortex_a510_core_pwr_dwn
 endfunc cortex_a510_core_pwr_dwn
 
 	/*
-	 * Errata printing function for Cortex A510. Must follow AAPCS.
+	 * Errata printing function for Cortex-A510. Must follow AAPCS.
 	 */
 #if REPORT_ERRATA
 func cortex_a510_errata_report
+	stp	x8, x30, [sp, #-16]!
+
+	bl	cpu_get_rev_var
+	mov	x8, x0
+
+	/*
+	 * Report all errata. The revision-variant information is passed to
+	 * checking functions of each errata.
+	 */
+	report_errata ERRATA_A510_1922240, cortex_a510, 1922240
+
+	ldp	x8, x30, [sp], #16
 	ret
 endfunc cortex_a510_errata_report
 #endif
 
 func cortex_a510_reset_func
+	mov	x19, x30
+
 	/* Disable speculative loads */
 	msr	SSBS, xzr
 	isb
-	ret
+
+	/* Get the CPU revision and stash it in x18. */
+	bl	cpu_get_rev_var
+	mov	x18, x0
+
+#if ERRATA_A510_1922240
+	mov	x0, x18
+	bl	errata_cortex_a510_1922240_wa
+#endif
+
+	ret	x19
 endfunc cortex_a510_reset_func
 
 	/* ---------------------------------------------

lib/cpus/cpu-ops.mk

@@ -451,6 +451,22 @@ ERRATA_A710_2083908	?=0
 # to revisions r0p0, r1p0 and r2p0 of the Cortex-A710 cpu and is still open.
 ERRATA_A710_2058056	?=0
 
+# Flag to apply erratum 2055002 workaround during reset. This erratum applies
+# to revision r1p0, r2p0 of the Cortex-A710 cpu and is still open.
+ERRATA_A710_2055002	?=0
+
+# Flag to apply erratum 2017096 workaround during reset. This erratum applies
+# to revision r0p0, r1p0 and r2p0 of the Cortex-A710 cpu and is still open.
+ERRATA_A710_2017096	?=0
+
+# Flag to apply erratum 2267065 workaround during reset. This erratum applies
+# to revision r0p0, r1p0 and r2p0 of the Cortex-A710 cpu and is fixed in r2p1.
+ERRATA_A710_2267065	?=0
+
+# Flag to apply erratum 2136059 workaround during reset. This erratum applies
+# to revision r0p0, r1p0 and r2p0 of the Cortex-A710 cpu and is fixed in r2p1.
+ERRATA_A710_2136059	?=0
+
 # Flag to apply erratum 2067956 workaround during reset. This erratum applies
 # to revision r0p0 of the Neoverse N2 cpu and is still open.
 ERRATA_N2_2067956	?=0
@@ -487,22 +503,6 @@ ERRATA_N2_2242400	?=0
 # to revision r0p0 of the Neoverse N2 cpu and is still open.
 ERRATA_N2_2280757	?=0
 
-# Flag to apply erratum 2055002 workaround during reset. This erratum applies
-# to revision r1p0, r2p0 of the Cortex-A710 cpu and is still open.
-ERRATA_A710_2055002	?=0
-
-# Flag to apply erratum 2017096 workaround during reset. This erratum applies
-# to revision r0p0, r1p0 and r2p0 of the Cortex-A710 cpu and is still open.
-ERRATA_A710_2017096	?=0
-
-# Flag to apply erratum 2267065 workaround during reset. This erratum applies
-# to revision r0p0, r1p0 and r2p0 of the Cortex-A710 cpu and is fixed in r2p1.
-ERRATA_A710_2267065	?=0
-
-# Flag to apply erratum 2136059 workaround during reset. This erratum applies
-# to revision r0p0, r1p0 and r2p0 of the Cortex-A710 cpu and is fixed in r2p1.
-ERRATA_A710_2136059	?=0
-
 # Flag to apply erratum 2002765 workaround during reset. This erratum applies
 # to revisions r0p0, r1p0, and r2p0 of the Cortex-X2 cpu and is still open.
 ERRATA_X2_2002765	?=0
@@ -530,6 +530,10 @@ ERRATA_X2_2081180	?=0
 # r2p1.
 ERRATA_X2_2216384	?=0
 
+# Flag to apply erratum 1922240 workaround during reset. This erratum applies
+# to revision r0p0 of the Cortex-A510 cpu and is fixed in r0p1.
+ERRATA_A510_1922240	?=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
@@ -911,6 +915,22 @@ $(eval $(call add_define,ERRATA_A710_2083908))
 $(eval $(call assert_boolean,ERRATA_A710_2058056))
 $(eval $(call add_define,ERRATA_A710_2058056))
 
+# Process ERRATA_A710_2055002 flag
+$(eval $(call assert_boolean,ERRATA_A710_2055002))
+$(eval $(call add_define,ERRATA_A710_2055002))
+
+# Process ERRATA_A710_2017096 flag
+$(eval $(call assert_boolean,ERRATA_A710_2017096))
+$(eval $(call add_define,ERRATA_A710_2017096))
+
+# Process ERRATA_A710_2267065 flag
+$(eval $(call assert_boolean,ERRATA_A710_2267065))
+$(eval $(call add_define,ERRATA_A710_2267065))
+
+# Process ERRATA_A710_2136059 flag
+$(eval $(call assert_boolean,ERRATA_A710_2136059))
+$(eval $(call add_define,ERRATA_A710_2136059))
+
 # Process ERRATA_N2_2067956 flag
 $(eval $(call assert_boolean,ERRATA_N2_2067956))
 $(eval $(call add_define,ERRATA_N2_2067956))
@@ -947,22 +967,6 @@ $(eval $(call add_define,ERRATA_N2_2242400))
 $(eval $(call assert_boolean,ERRATA_N2_2280757))
 $(eval $(call add_define,ERRATA_N2_2280757))
 
-# Process ERRATA_A710_2055002 flag
-$(eval $(call assert_boolean,ERRATA_A710_2055002))
-$(eval $(call add_define,ERRATA_A710_2055002))
-
-# Process ERRATA_A710_2017096 flag
-$(eval $(call assert_boolean,ERRATA_A710_2017096))
-$(eval $(call add_define,ERRATA_A710_2017096))
-
-# Process ERRATA_A710_2267065 flag
-$(eval $(call assert_boolean,ERRATA_A710_2267065))
-$(eval $(call add_define,ERRATA_A710_2267065))
-
-# Process ERRATA_A710_2136059 flag
-$(eval $(call assert_boolean,ERRATA_A710_2136059))
-$(eval $(call add_define,ERRATA_A710_2136059))
-
 # Process ERRATA_X2_2002765 flag
 $(eval $(call assert_boolean,ERRATA_X2_2002765))
 $(eval $(call add_define,ERRATA_X2_2002765))
@@ -987,6 +991,10 @@ $(eval $(call add_define,ERRATA_X2_2081180))
 $(eval $(call assert_boolean,ERRATA_X2_2216384))
 $(eval $(call add_define,ERRATA_X2_2216384))
 
+# Process ERRATA_A510_1922240 flag
+$(eval $(call assert_boolean,ERRATA_A510_1922240))
+$(eval $(call add_define,ERRATA_A510_1922240))
+
 # Process ERRATA_DSU_798953 flag
 $(eval $(call assert_boolean,ERRATA_DSU_798953))
 $(eval $(call add_define,ERRATA_DSU_798953))