Cortex-A17: Implement workaround for errata 852423

Change-Id: I3a101e540f0b134ecf9a51fa3d7d8e3d0369b297
Signed-off-by: Ambroise Vincent <ambroise.vincent@arm.com>

diff --git a/docs/cpu-specific-build-macros.rst b/docs/cpu-specific-build-macros.rst
index ae0cfd9c2b87382126f4ed8a6e47f7dd99f55f2b..ca3366dc593d45f3ece12191a67e5ac1ee1bb820 100644 (file)
--- a/docs/cpu-specific-build-macros.rst
+++ b/docs/cpu-specific-build-macros.rst
@@ -84,6 +84,9 @@ For Cortex-A17, the following errata build flags are defined :
 -  ``ERRATA_A17_852421``: This applies errata 852421 workaround to Cortex-A17
    CPU. This needs to be enabled only for revision <= r1p2 of the CPU.
 
+-  ``ERRATA_A17_852423``: This applies errata 852423 workaround to Cortex-A17
+   CPU. This needs to be enabled only for revision <= r1p2 of the CPU.
+
 For Cortex-A53, the following errata build flags are defined :
 
 -  ``ERRATA_A53_819472``: This applies errata 819472 workaround to all

diff --git a/lib/cpus/aarch32/cortex_a17.S b/lib/cpus/aarch32/cortex_a17.S
index 87e8c8d02b1120c359158a717f3f3ba5af7798d0..b8abd3361fcb7d36d26c8220bbc2c82aedd8173d 100644 (file)
--- a/lib/cpus/aarch32/cortex_a17.S
+++ b/lib/cpus/aarch32/cortex_a17.S
@@ -63,6 +63,34 @@ func check_errata_852421
        b       cpu_rev_var_ls
 endfunc check_errata_852421
 
+       /* ----------------------------------------------------
+        * Errata Workaround for Cortex A17 Errata #852423.
+        * This applies only to revision <= r1p2 of Cortex A17.
+        * Inputs:
+        * r0: variant[4:7] and revision[0:3] of current cpu.
+        * Shall clobber: r0-r3
+        * ----------------------------------------------------
+        */
+func errata_a17_852423_wa
+       /*
+        * Compare r0 against revision r1p2
+        */
+       mov     r2, lr
+       bl      check_errata_852423
+       cmp     r0, #ERRATA_NOT_APPLIES
+       beq     1f
+       ldcopr  r0, CORTEX_A17_IMP_DEF_REG1
+       orr     r0, r0, #(1<<12)
+       stcopr  r0, CORTEX_A17_IMP_DEF_REG1
+1:
+       bx      r2
+endfunc errata_a17_852423_wa
+
+func check_errata_852423
+       mov     r1, #0x12
+       b       cpu_rev_var_ls
+endfunc check_errata_852423
+
 func check_errata_cve_2017_5715
 #if WORKAROUND_CVE_2017_5715
        mov     r0, #ERRATA_APPLIES
@@ -87,6 +115,7 @@ func cortex_a17_errata_report
         * checking functions of each errata.
         */
        report_errata ERRATA_A17_852421, cortex_a17, 852421
+       report_errata ERRATA_A17_852423, cortex_a17, 852423
        report_errata WORKAROUND_CVE_2017_5715, cortex_a17, cve_2017_5715
 
        pop     {r12, lr}
@@ -97,11 +126,18 @@ endfunc cortex_a17_errata_report
 func cortex_a17_reset_func
        mov     r5, lr
        bl      cpu_get_rev_var
+       mov     r4, r0
 
 #if ERRATA_A17_852421
+       mov     r0, r4
        bl      errata_a17_852421_wa
 #endif
 
+#if ERRATA_A17_852423
+       mov     r0, r4
+       bl      errata_a17_852423_wa
+#endif
+
 #if IMAGE_BL32 && WORKAROUND_CVE_2017_5715
        ldr     r0, =workaround_bpiall_runtime_exceptions
        stcopr  r0, VBAR

diff --git a/lib/cpus/cpu-ops.mk b/lib/cpus/cpu-ops.mk
index 9ccd78779340530c25044933ba67180c899b4fc0..c42eb1cde50bde755421af1a0aaa0606d61eaf8e 100644 (file)
--- a/lib/cpus/cpu-ops.mk
+++ b/lib/cpus/cpu-ops.mk
@@ -65,6 +65,10 @@ ERRATA_A15_827671    ?=0
 # only to revision <= r1p2 of the Cortex A17 cpu.
 ERRATA_A17_852421      ?=0
 
+# Flag to apply erratum 852423 workaround during reset. This erratum applies
+# only to revision <= r1p2 of the Cortex A17 cpu.
+ERRATA_A17_852423      ?=0
+
 # Flag to apply erratum 819472 workaround during reset. This erratum applies
 # only to revision <= r0p1 of the Cortex A53 cpu.
 ERRATA_A53_819472      ?=0
@@ -220,6 +224,10 @@ $(eval $(call add_define,ERRATA_A15_827671))
 $(eval $(call assert_boolean,ERRATA_A17_852421))
 $(eval $(call add_define,ERRATA_A17_852421))
 
+# Process ERRATA_A17_852423 flag
+$(eval $(call assert_boolean,ERRATA_A17_852423))
+$(eval $(call add_define,ERRATA_A17_852423))
+
 # Process ERRATA_A53_819472 flag
 $(eval $(call assert_boolean,ERRATA_A53_819472))
 $(eval $(call add_define,ERRATA_A53_819472))