refactor(cpus): convert the Cortex-A75 to use the errata framework

This involves replacing:
 * the reset_func with the standard cpu_reset_func_{start,end} to apply
   errata automatically
 * the <cpu>_errata_report with the errata_report_shim to report errata
   automatically
...and for each erratum:
 * the prologue with the workaround_<type>_start to do the checks and
   framework registration automatically
 * the epilogue with the workaround_<type>_end
 * the checker function with the check_erratum_<type> to make it more
   descriptive

It is important to note that the errata workaround sequences remain
unchanged and preserve their git blame.

Testing was conducted by:
 * Building for release with all errata flags enabled and running script
   in change 19136 to compare output of objdump for each errata. Only
   ERRATA_A75_764081 and ERRATA_A75_790748 could be verified this way,
   rest had to be manually verified.
 * Manual comparison of disassembly of converted functions with non-
   converted functions

   aarch64-none-elf-objdump -D <trusted-firmware-a with conversion>/build/fvp/release/bl31/bl31.elf
     vs
   aarch64-none-elf-objdump -D <trusted-firmware-a clean repo>/build/fvp/release/bl31/bl31.elf

 * Build for release with all errata flags enabled and run default tftf
   tests

   CROSS_COMPILE=aarch64-none-elf- make PLAT=fvp HW_ASSISTED_COHERENCY=1 \
   USE_COHERENT_MEM=0 CTX_INCLUDE_AARCH32_REGS=1 \
   BL33=/home/katcap01/tf-a-tests/build/fvp/debug/tftf.bin \
   ERRATA_A75_764081=1 ERRATA_A75_790748=1 WORKAROUND_CVE_2017_5715=1 \
   WORKAROUND_CVE_2018_3639=1 \
   ERRATA_DSU_798953=1 ERRATA_DSU_936184=1 \
   WORKAROUND_CVE_2022_23960=1 \
   fip all

 * Build for debug with all errata enabled and step through ArmDS
   at reset to ensure all functions are entered.
Signed-off-by: Kathleen Capella <kathleen.capella@arm.com>
Change-Id: I0cd393db825fcb5c7ddea3aa2a5934ffc4b6046e
diff --git a/lib/cpus/aarch64/cortex_a75.S b/lib/cpus/aarch64/cortex_a75.S
index e22c828..3ef72c6 100644
--- a/lib/cpus/aarch64/cortex_a75.S
+++ b/lib/cpus/aarch64/cortex_a75.S
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017-2022, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2017-2023, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -15,112 +15,103 @@
 #error "Cortex-A75 must be compiled with HW_ASSISTED_COHERENCY enabled"
 #endif
 
-	/* --------------------------------------------------
-	 * Errata Workaround for Cortex A75 Errata #764081.
-	 * This applies only to revision r0p0 of Cortex A75.
-	 * Inputs:
-	 * x0: variant[4:7] and revision[0:3] of current cpu.
-	 * Shall clobber: x0-x17
-	 * --------------------------------------------------
-	 */
-func errata_a75_764081_wa
-	/*
-	 * Compare x0 against revision r0p0
-	 */
-	mov	x17, x30
-	bl	check_errata_764081
-	cbz	x0, 1f
+workaround_reset_start cortex_a75, ERRATUM(764081), ERRATA_A75_764081
 	mrs	x1, sctlr_el3
 	orr	x1, x1 ,#SCTLR_IESB_BIT
 	msr	sctlr_el3, x1
-	isb
-1:
-	ret	x17
-endfunc errata_a75_764081_wa
+workaround_reset_end cortex_a75, ERRATUM(764081)
 
-func check_errata_764081
-	mov	x1, #0x00
-	b	cpu_rev_var_ls
-endfunc check_errata_764081
+check_erratum_ls cortex_a75, ERRATUM(764081), CPU_REV(0, 0)
 
-	/* --------------------------------------------------
-	 * Errata Workaround for Cortex A75 Errata #790748.
-	 * This applies only to revision r0p0 of Cortex A75.
-	 * Inputs:
-	 * x0: variant[4:7] and revision[0:3] of current cpu.
-	 * Shall clobber: x0-x17
-	 * --------------------------------------------------
-	 */
-func errata_a75_790748_wa
-	/*
-	 * Compare x0 against revision r0p0
-	 */
-	mov	x17, x30
-	bl	check_errata_790748
-	cbz	x0, 1f
+workaround_reset_start cortex_a75, ERRATUM(790748), ERRATA_A75_790748
 	mrs	x1, CORTEX_A75_CPUACTLR_EL1
 	orr	x1, x1 ,#(1 << 13)
 	msr	CORTEX_A75_CPUACTLR_EL1, x1
-	isb
-1:
-	ret	x17
-endfunc errata_a75_790748_wa
-
-func check_errata_790748
-	mov	x1, #0x00
-	b	cpu_rev_var_ls
-endfunc check_errata_790748
+workaround_reset_end cortex_a75, ERRATUM(790748)
 
-	/* -------------------------------------------------
-	 * The CPU Ops reset function for Cortex-A75.
-	 * -------------------------------------------------
-	 */
-func cortex_a75_reset_func
-	mov	x19, x30
-	bl	cpu_get_rev_var
-	mov	x18, x0
+check_erratum_ls cortex_a75, ERRATUM(790748), CPU_REV(0, 0)
 
-#if ERRATA_A75_764081
-	mov	x0, x18
-	bl	errata_a75_764081_wa
-#endif
+/* ERRATA_DSU_798953 :
+ * The errata is defined in dsu_helpers.S but applies to cortex_a75
+ * as well. Henceforth creating symbolic names to the already existing errata
+ * workaround functions to get them registered under the Errata Framework.
+ */
+.equ check_erratum_cortex_a75_798953, check_errata_dsu_798953
+.equ erratum_cortex_a75_798953_wa, errata_dsu_798953_wa
+add_erratum_entry cortex_a75, ERRATUM(798953), ERRATA_DSU_798953, APPLY_AT_RESET
 
-#if ERRATA_A75_790748
-	mov	x0, x18
-	bl	errata_a75_790748_wa
-#endif
+/* ERRATA_DSU_936184 :
+ * The errata is defined in dsu_helpers.S but applies to cortex_a75
+ * as well. Henceforth creating symbolic names to the already existing errata
+ * workaround functions to get them registered under the Errata Framework.
+ */
+.equ check_erratum_cortex_a75_936184, check_errata_dsu_936184
+.equ erratum_cortex_a75_936184_wa, errata_dsu_936184_wa
+add_erratum_entry cortex_a75, ERRATUM(936184), ERRATA_DSU_936184, APPLY_AT_RESET
 
-#if IMAGE_BL31 && (WORKAROUND_CVE_2017_5715 || WORKAROUND_CVE_2022_23960)
-	cpu_check_csv2	x0, 1f
-	adr	x0, wa_cve_2017_5715_bpiall_vbar
-	msr	vbar_el3, x0
-	isb
-	/* Skip installing vector table again for CVE_2022_23960 */
-        b       2f
-1:
-#if WORKAROUND_CVE_2022_23960
+workaround_reset_start cortex_a75, CVE(2017, 5715), WORKAROUND_CVE_2017_5715
+#if IMAGE_BL31
 	adr	x0, wa_cve_2017_5715_bpiall_vbar
 	msr	vbar_el3, x0
-	isb
+#endif /* IMAGE_BL31 */
+workaround_reset_end cortex_a75, CVE(2017, 5715)
+
+check_erratum_custom_start cortex_a75, CVE(2017, 5715)
+	cpu_check_csv2	x0, 1f
+#if WORKAROUND_CVE_2017_5715
+	mov	x0, #ERRATA_APPLIES
+#else
+	mov	x0, #ERRATA_MISSING
 #endif
-2:
-#endif /* IMAGE_BL31 &&  (WORKAROUND_CVE_2017_5715 || WORKAROUND_CVE_2022_23960) */
+	ret
+1:
+	mov	x0, #ERRATA_NOT_APPLIES
+	ret
+check_erratum_custom_end cortex_a75, CVE(2017, 5715)
 
-#if WORKAROUND_CVE_2018_3639
+workaround_reset_start cortex_a75, CVE(2018, 3639), WORKAROUND_CVE_2018_3639
 	mrs	x0, CORTEX_A75_CPUACTLR_EL1
 	orr	x0, x0, #CORTEX_A75_CPUACTLR_EL1_DISABLE_LOAD_PASS_STORE
 	msr	CORTEX_A75_CPUACTLR_EL1, x0
-	isb
-#endif
+workaround_reset_end cortex_a75, CVE(2018, 3639)
 
-#if ERRATA_DSU_798953
-	bl	errata_dsu_798953_wa
-#endif
+check_erratum_chosen cortex_a75, CVE(2018, 3639), WORKAROUND_CVE_2018_3639
 
-#if ERRATA_DSU_936184
-	bl	errata_dsu_936184_wa
-#endif
+workaround_reset_start cortex_a75, CVE(2022, 23960), WORKAROUND_CVE_2022_23960
+#if IMAGE_BL31
+	/* Skip installing vector table again if already done for CVE(2017, 5715) */
+	adr	x0, wa_cve_2017_5715_bpiall_vbar
+	mrs	x1, vbar_el3
+	cmp	x0, x1
+	b.eq	1f
+	msr	vbar_el3, x0
+1:
+#endif /* IMAGE_BL31 */
+workaround_reset_end cortex_a75, CVE(2022, 23960)
+
+check_erratum_custom_start cortex_a75, CVE(2022, 23960)
+#if WORKAROUND_CVE_2017_5715 || WORKAROUND_CVE_2022_23960
+	cpu_check_csv2	x0, 1f
+	mov	x0, #ERRATA_APPLIES
+	ret
+1:
+# if WORKAROUND_CVE_2022_23960
+	mov	x0, #ERRATA_APPLIES
+# else
+	mov	x0, #ERRATA_MISSING
+# endif /* WORKAROUND_CVE_2022_23960 */
+	ret
+#endif /* WORKAROUND_CVE_2017_5715 || WORKAROUND_CVE_2022_23960 */
+	mov	x0, #ERRATA_MISSING
+	ret
+check_erratum_custom_end cortex_a75, CVE(2022, 23960)
 
+	/* -------------------------------------------------
+	 * The CPU Ops reset function for Cortex-A75.
+	 * -------------------------------------------------
+	 */
+
+cpu_reset_func_start cortex_a75
 #if ENABLE_FEAT_AMU
 	/* Make sure accesses from EL0/EL1 and EL2 are not trapped to EL3 */
 	mrs	x0, actlr_el3
@@ -142,49 +133,9 @@
 	/* Enable group1 counters */
 	mov	x0, #CORTEX_A75_AMU_GROUP1_MASK
 	msr	CPUAMCNTENSET_EL0, x0
-	isb
-#endif
-	ret	x19
-endfunc cortex_a75_reset_func
-
-func check_errata_cve_2017_5715
-	cpu_check_csv2	x0, 1f
-#if WORKAROUND_CVE_2017_5715
-	mov	x0, #ERRATA_APPLIES
-#else
-	mov	x0, #ERRATA_MISSING
-#endif
-	ret
-1:
-	mov	x0, #ERRATA_NOT_APPLIES
-	ret
-endfunc check_errata_cve_2017_5715
-
-func check_errata_cve_2018_3639
-#if WORKAROUND_CVE_2018_3639
-	mov	x0, #ERRATA_APPLIES
-#else
-	mov	x0, #ERRATA_MISSING
+	/* isb included in cpu_reset_func_end macro */
 #endif
-	ret
-endfunc check_errata_cve_2018_3639
-
-func check_errata_cve_2022_23960
-#if WORKAROUND_CVE_2017_5715 || WORKAROUND_CVE_2022_23960
-	cpu_check_csv2	x0, 1f
-	mov	x0, #ERRATA_APPLIES
-	ret
-1:
-# if WORKAROUND_CVE_2022_23960
-	mov	x0, #ERRATA_APPLIES
-# else
-	mov	x0, #ERRATA_MISSING
-# endif /* WORKAROUND_CVE_2022_23960 */
-	ret
-#endif /* WORKAROUND_CVE_2017_5715 || WORKAROUND_CVE_2022_23960 */
-	mov	x0, #ERRATA_MISSING
-	ret
-endfunc check_errata_cve_2022_23960
+cpu_reset_func_end cortex_a75
 
 func check_smccc_arch_workaround_3
 	mov	x0, #ERRATA_APPLIES
@@ -207,32 +158,7 @@
 	ret
 endfunc cortex_a75_core_pwr_dwn
 
-#if REPORT_ERRATA
-/*
- * Errata printing function for Cortex A75. Must follow AAPCS.
- */
-func cortex_a75_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_A75_764081, cortex_a75, 764081
-	report_errata ERRATA_A75_790748, cortex_a75, 790748
-	report_errata WORKAROUND_CVE_2017_5715, cortex_a75, cve_2017_5715
-	report_errata WORKAROUND_CVE_2018_3639, cortex_a75, cve_2018_3639
-	report_errata ERRATA_DSU_798953, cortex_a75, dsu_798953
-	report_errata ERRATA_DSU_936184, cortex_a75, dsu_936184
-	report_errata WORKAROUND_CVE_2022_23960, cortex_a75, cve_2022_23960
-
-	ldp	x8, x30, [sp], #16
-	ret
-endfunc cortex_a75_errata_report
-#endif
+errata_report_shim cortex_a75
 
 	/* ---------------------------------------------
 	 * This function provides cortex_a75 specific
@@ -255,7 +181,7 @@
 
 declare_cpu_ops_wa cortex_a75, CORTEX_A75_MIDR, \
 	cortex_a75_reset_func, \
-	check_errata_cve_2017_5715, \
+	check_erratum_cortex_a75_5715, \
 	CPU_NO_EXTRA2_FUNC, \
 	check_smccc_arch_workaround_3, \
 	cortex_a75_core_pwr_dwn