feat(rmmd): add support for RMM Boot interface

This patch adds the infrastructure needed to pass boot arguments from
EL3 to RMM and allocates a shared buffer between both worlds that can
be used, among others, to pass a boot manifest to RMM. The buffer is
composed a single memory page be used by a later EL3 <-> RMM interface
by all CPUs.

The RMM boot manifest is not implemented by this patch.

In addition to that, this patch also enables support for RMM when
RESET_TO_BL31 is enabled.

Signed-off-by: Javier Almansa Sobrino <javier.almansasobrino@arm.com>
Change-Id: I855cd4758ee3843eadd9fb482d70a6d18954d82a
diff --git a/services/std_svc/rmmd/trp/trp_main.c b/services/std_svc/rmmd/trp/trp_main.c
index 2e3f076..7df128b 100644
--- a/services/std_svc/rmmd/trp/trp_main.c
+++ b/services/std_svc/rmmd/trp/trp_main.c
@@ -13,6 +13,10 @@
 #include <platform_def.h>
 #include "trp_private.h"
 
+/* Parameters received from the previous image */
+static unsigned int trp_boot_abi_version;
+static uintptr_t trp_shared_region_start;
+
 /*******************************************************************************
  * Per cpu data structure to populate parameters for an SMC in C code and use
  * a pointer to this structure in assembler code to populate x0-x7
@@ -52,11 +56,55 @@
 	return pcpu_smc_args;
 }
 
+/*
+ * Abort the boot process with the reason given in err.
+ */
+__dead2 static void trp_boot_abort(uint64_t err)
+{
+	(void)trp_smc(set_smc_args(RMM_BOOT_COMPLETE, err, 0, 0, 0, 0, 0, 0));
+	panic();
+}
+
 /*******************************************************************************
  * Setup function for TRP.
  ******************************************************************************/
-void trp_setup(void)
+void trp_setup(uint64_t x0,
+	       uint64_t x1,
+	       uint64_t x2,
+	       uint64_t x3)
 {
+	/*
+	 * Validate boot parameters.
+	 *
+	 * According to the Boot Interface ABI v.0.1, the
+	 * parameters recived from EL3 are:
+	 * x0: CPUID (verified earlier so not used)
+	 * x1: Boot Interface version
+	 * x2: PLATFORM_CORE_COUNT
+	 * x3: Pointer to the shared memory area.
+	 */
+
+	(void)x0;
+
+	if (TRP_RMM_EL3_VERSION_GET_MAJOR(x1) != TRP_RMM_EL3_ABI_VERS_MAJOR) {
+		trp_boot_abort(E_RMM_BOOT_VERSION_MISMATCH);
+	}
+
+	if ((void *)x3 == NULL) {
+		trp_boot_abort(E_RMM_BOOT_INVALID_SHARED_BUFFER);
+	}
+
+	if (x2 > TRP_PLATFORM_CORE_COUNT) {
+		trp_boot_abort(E_RMM_BOOT_CPUS_OUT_OF_RANGE);
+	}
+
+	trp_boot_abi_version = x1;
+	trp_shared_region_start = x3;
+	flush_dcache_range((uintptr_t)&trp_boot_abi_version,
+			   sizeof(trp_boot_abi_version));
+	flush_dcache_range((uintptr_t)&trp_shared_region_start,
+			   sizeof(trp_shared_region_start));
+
 	/* Perform early platform-specific setup */
 	trp_early_platform_setup();
 }
@@ -66,9 +114,16 @@
 {
 	NOTICE("TRP: %s\n", version_string);
 	NOTICE("TRP: %s\n", build_message);
+	NOTICE("TRP: Supported RMM-EL3 Interface ABI: v.%u.%u\n",
+		TRP_RMM_EL3_ABI_VERS_MAJOR, TRP_RMM_EL3_ABI_VERS_MINOR);
 	INFO("TRP: Memory base : 0x%lx\n", (unsigned long)RMM_BASE);
+	INFO("TRP: Base address for the shared region : 0x%lx\n",
+			(unsigned long)trp_shared_region_start);
 	INFO("TRP: Total size : 0x%lx bytes\n", (unsigned long)(RMM_END
 								- RMM_BASE));
+	INFO("TRP: RMM-EL3 Interface ABI reported by EL3: v.%u.%u\n",
+		TRP_RMM_EL3_VERSION_GET_MAJOR(trp_boot_abi_version),
+		TRP_RMM_EL3_VERSION_GET_MINOR(trp_boot_abi_version));
 }
 
 /*******************************************************************************