feat(cpus): add support for Gelas CPU

This patch adds the necessary CPU library code to support the Gelas CPU

Change-Id: I13ec4a8bb7055c1ebd0796a4a1378983d930fcb3
Signed-off-by: Juan Pablo Conde <juanpablo.conde@arm.com>

3 files changed, 110 insertions, 1 deletions

diff --git a/include/lib/cpus/aarch64/cortex_gelas.h b/include/lib/cpus/aarch64/cortex_gelas.h
new file mode 100644
index 000000000..90bb78fee
--- /dev/null
+++ b/include/lib/cpus/aarch64/cortex_gelas.h
@@ -0,0 +1,31 @@
+/*
+ * Copyright (c) 2023, Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef CORTEX_GELAS_H
+#define CORTEX_GELAS_H
+
+#include <lib/utils_def.h>
+
+#define CORTEX_GELAS_MIDR				U(0x410FD8B0)
+
+/*******************************************************************************
+ * CPU Extended Control register specific definitions
+ ******************************************************************************/
+#define CORTEX_GELAS_IMP_CPUECTLR_EL1			S3_0_C15_C1_5
+
+/*******************************************************************************
+ * CPU Power Control register specific definitions
+ ******************************************************************************/
+#define CORTEX_GELAS_CPUPWRCTLR_EL1			S3_0_C15_C2_7
+#define CORTEX_GELAS_CPUPWRCTLR_EL1_CORE_PWRDN_BIT	U(1)
+
+/*******************************************************************************
+ * SME Control registers
+ ******************************************************************************/
+#define CORTEX_GELAS_SVCRSM				S0_3_C4_C2_3
+#define CORTEX_GELAS_SVCRZA				S0_3_C4_C4_3
+
+#endif /* CORTEX_GELAS_H */
diff --git a/lib/cpus/aarch64/cortex_gelas.S b/lib/cpus/aarch64/cortex_gelas.S
new file mode 100644
index 000000000..e0d20a9e7
--- /dev/null
+++ b/lib/cpus/aarch64/cortex_gelas.S
@@ -0,0 +1,77 @@
+/*
+ * Copyright (c) 2023, Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <arch.h>
+#include <asm_macros.S>
+#include <common/bl_common.h>
+#include <cortex_gelas.h>
+#include <cpu_macros.S>
+#include <plat_macros.S>
+
+/* Hardware handled coherency */
+#if HW_ASSISTED_COHERENCY == 0
+#error "Gelas must be compiled with HW_ASSISTED_COHERENCY enabled"
+#endif
+
+/* 64-bit only core */
+#if CTX_INCLUDE_AARCH32_REGS == 1
+#error "Gelas supports only AArch64. Compile with CTX_INCLUDE_AARCH32_REGS=0"
+#endif
+
+cpu_reset_func_start cortex_gelas
+	/* ----------------------------------------------------
+	 * Disable speculative loads
+	 * ----------------------------------------------------
+	 */
+	msr	SSBS, xzr
+cpu_reset_func_end cortex_gelas
+
+	/* ----------------------------------------------------
+	 * HW will do the cache maintenance while powering down
+	 * ----------------------------------------------------
+	 */
+func cortex_gelas_core_pwr_dwn
+        /* ---------------------------------------------------
+         * Disable SME
+         * ---------------------------------------------------
+         */
+	msr	CORTEX_GELAS_SVCRSM, xzr
+	msr	CORTEX_GELAS_SVCRZA, xzr
+
+	/* ---------------------------------------------------
+	 * Enable CPU power down bit in power control register
+	 * ---------------------------------------------------
+	 */
+	sysreg_bit_set 	CORTEX_GELAS_CPUPWRCTLR_EL1, \
+		CORTEX_GELAS_CPUPWRCTLR_EL1_CORE_PWRDN_BIT
+	isb
+	ret
+endfunc cortex_gelas_core_pwr_dwn
+
+errata_report_shim cortex_gelas
+
+	/* ---------------------------------------------
+	 * This function provides Gelas 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.cortex_gelas_regs, "aS"
+cortex_gelas_regs: /* The ASCII list of register names to be reported */
+	.asciz	"imp_cpuectlr_el1", ""
+
+func cortex_gelas_cpu_reg_dump
+	adr	x6, cortex_gelas_regs
+	mrs	x8, CORTEX_GELAS_IMP_CPUECTLR_EL1
+	ret
+endfunc cortex_gelas_cpu_reg_dump
+
+declare_cpu_ops cortex_gelas, CORTEX_GELAS_MIDR, \
+	cortex_gelas_reset_func, \
+	cortex_gelas_core_pwr_dwn
diff --git a/plat/arm/board/fvp/platform.mk b/plat/arm/board/fvp/platform.mk
index e790f927c..6ac4e092a 100644
--- a/plat/arm/board/fvp/platform.mk
+++ b/plat/arm/board/fvp/platform.mk
@@ -213,7 +213,8 @@ else
 					lib/cpus/aarch64/neoverse_n2.S		\
 					lib/cpus/aarch64/neoverse_v1.S		\
 					lib/cpus/aarch64/neoverse_e1.S		\
-					lib/cpus/aarch64/cortex_x2.S
+					lib/cpus/aarch64/cortex_x2.S		\
+					lib/cpus/aarch64/cortex_gelas.S
 	endif
 	# AArch64/AArch32 cores
 	FVP_CPU_LIBS	+=	lib/cpus/aarch64/cortex_a55.S		\