Add support for Neoverse-N2 CPUs.
Enable basic support for Neoverse-N2 CPUs.
Signed-off-by: Javier Almansa Sobrino <javier.almansasobrino@arm.com>
Change-Id: I498adc2d9fc61ac6e1af8ece131039410872e8ad
diff --git a/lib/cpus/aarch64/neoverse_n2.S b/lib/cpus/aarch64/neoverse_n2.S
new file mode 100644
index 0000000..8d646cb
--- /dev/null
+++ b/lib/cpus/aarch64/neoverse_n2.S
@@ -0,0 +1,109 @@
+/*
+ * Copyright (c) 2020, Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <arch.h>
+#include <asm_macros.S>
+#include <cpu_macros.S>
+#include <neoverse_n2.h>
+
+/* Hardware handled coherency */
+#if HW_ASSISTED_COHERENCY == 0
+#error "Neoverse N2 must be compiled with HW_ASSISTED_COHERENCY enabled"
+#endif
+
+/* 64-bit only core */
+#if CTX_INCLUDE_AARCH32_REGS == 1
+#error "Neoverse-N2 supports only AArch64. Compile with CTX_INCLUDE_AARCH32_REGS=0"
+#endif
+
+ /* -------------------------------------------------
+ * The CPU Ops reset function for Neoverse N2.
+ * -------------------------------------------------
+ */
+func neoverse_n2_reset_func
+ /* Check if the PE implements SSBS */
+ mrs x0, id_aa64pfr1_el1
+ tst x0, #(ID_AA64PFR1_EL1_SSBS_MASK << ID_AA64PFR1_EL1_SSBS_SHIFT)
+ b.eq 1f
+
+ /* Disable speculative loads */
+ msr SSBS, xzr
+1:
+ /* Force all cacheable atomic instructions to be near */
+ mrs x0, NEOVERSE_N2_CPUACTLR2_EL1
+ orr x0, x0, #NEOVERSE_N2_CPUACTLR2_EL1_BIT_2
+ msr NEOVERSE_N2_CPUACTLR2_EL1, x0
+
+#if ENABLE_AMU
+ /* Make sure accesses from EL0/EL1 and EL2 are not trapped to EL3 */
+ mrs x0, cptr_el3
+ orr x0, x0, #TAM_BIT
+ msr cptr_el3, x0
+
+ /* Make sure accesses from EL0/EL1 are not trapped to EL2 */
+ mrs x0, cptr_el2
+ orr x0, x0, #TAM_BIT
+ msr cptr_el2, x0
+
+ /* No need to enable the counters as this would be done at el3 exit */
+#endif
+
+#if NEOVERSE_Nx_EXTERNAL_LLC
+ /* Some systems may have External LLC, core needs to be made aware */
+ mrs x0, NEOVERSE_N2_CPUECTLR_EL1
+ orr x0, x0, NEOVERSE_N2_CPUECTLR_EL1_EXTLLC_BIT
+ msr NEOVERSE_N2_CPUECTLR_EL1, x0
+#endif
+
+ isb
+ ret
+endfunc neoverse_n2_reset_func
+
+func neoverse_n2_core_pwr_dwn
+ /* ---------------------------------------------
+ * Enable CPU power down bit in power control register
+ * No need to do cache maintenance here.
+ * ---------------------------------------------
+ */
+ mrs x0, NEOVERSE_N2_CPUPWRCTLR_EL1
+ orr x0, x0, #NEOVERSE_N2_CORE_PWRDN_EN_BIT
+ msr NEOVERSE_N2_CPUPWRCTLR_EL1, x0
+ isb
+ ret
+endfunc neoverse_n2_core_pwr_dwn
+
+#if REPORT_ERRATA
+/*
+ * Errata printing function for Neoverse N2 cores. Must follow AAPCS.
+ */
+func neoverse_n2_errata_report
+ /* No errata reported for Neoverse N2 cores */
+ ret
+endfunc neoverse_n2_errata_report
+#endif
+
+ /* ---------------------------------------------
+ * This function provides Neoverse N2 specific
+ * register information for crash reporting.
+ * It needs to return with x6 pointing to
+ * a list of register names in ASCII and
+ * x8 - x15 having values of registers to be
+ * reported.
+ * ---------------------------------------------
+ */
+.section .rodata.neoverse_n2_regs, "aS"
+neoverse_n2_regs: /* The ASCII list of register names to be reported */
+ .asciz "cpupwrctlr_el1", ""
+
+func neoverse_n2_cpu_reg_dump
+ adr x6, neoverse_n2_regs
+ mrs x8, NEOVERSE_N2_CPUPWRCTLR_EL1
+ ret
+endfunc neoverse_n2_cpu_reg_dump
+
+declare_cpu_ops neoverse_n2, NEOVERSE_N2_MIDR, \
+ neoverse_n2_reset_func, \
+ neoverse_n2_core_pwr_dwn