debugfs: add SMC channel

Provide an SMC interface to the 9p filesystem. This permits
accessing firmware drivers through a common interface, using
standardized read/write/control operations.

Signed-off-by: Ambroise Vincent <ambroise.vincent@arm.com>
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
Change-Id: I9314662314bb060f6bc02714476574da158b2a7d
diff --git a/plat/arm/board/fvp/fvp_common.c b/plat/arm/board/fvp/fvp_common.c
index a948796..5c0df7a 100644
--- a/plat/arm/board/fvp/fvp_common.c
+++ b/plat/arm/board/fvp/fvp_common.c
@@ -122,6 +122,10 @@
 #ifdef IMAGE_BL31
 const mmap_region_t plat_arm_mmap[] = {
 	ARM_MAP_SHARED_RAM,
+#if USE_DEBUGFS
+	/* Required by devfip, can be removed if devfip is not used */
+	V2M_MAP_FLASH0_RW,
+#endif /* USE_DEBUGFS */
 	ARM_MAP_EL3_TZC_DRAM,
 	V2M_MAP_IOFPGA,
 	MAP_DEVICE0,
diff --git a/plat/arm/board/fvp/include/platform_def.h b/plat/arm/board/fvp/include/platform_def.h
index 98dd0a9..2b44174 100644
--- a/plat/arm/board/fvp/include/platform_def.h
+++ b/plat/arm/board/fvp/include/platform_def.h
@@ -68,7 +68,11 @@
 #  define PLAT_SP_IMAGE_MAX_XLAT_TABLES	10
 # else
 #  define PLAT_ARM_MMAP_ENTRIES		8
-#  define MAX_XLAT_TABLES		5
+#  if USE_DEBUGFS
+#   define MAX_XLAT_TABLES		6
+#  else
+#   define MAX_XLAT_TABLES		5
+#  endif
 # endif
 #elif defined(IMAGE_BL32)
 # define PLAT_ARM_MMAP_ENTRIES		8
diff --git a/plat/arm/board/fvp/platform.mk b/plat/arm/board/fvp/platform.mk
index 3a9972b..8cf2612 100644
--- a/plat/arm/board/fvp/platform.mk
+++ b/plat/arm/board/fvp/platform.mk
@@ -291,6 +291,10 @@
     endif
 endif
 
+ifeq (${USE_DEBUGFS},1)
+    BL31_CFLAGS	+=	-DPLAT_XLAT_TABLES_DYNAMIC=1
+endif
+
 # Add support for platform supplied linker script for BL31 build
 $(eval $(call add_define,PLAT_EXTRA_LD_SCRIPT))
 
diff --git a/plat/arm/common/arm_bl31_setup.c b/plat/arm/common/arm_bl31_setup.c
index ab90f46..939885f 100644
--- a/plat/arm/common/arm_bl31_setup.c
+++ b/plat/arm/common/arm_bl31_setup.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015-2018, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2019, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -11,6 +11,7 @@
 #include <common/bl_common.h>
 #include <common/debug.h>
 #include <drivers/console.h>
+#include <lib/debugfs.h>
 #include <lib/extensions/ras.h>
 #include <lib/mmio.h>
 #include <lib/utils.h>
@@ -231,6 +232,10 @@
 #if RAS_EXTENSION
 	ras_init();
 #endif
+
+#if USE_DEBUGFS
+	debugfs_init();
+#endif /* USE_DEBUGFS */
 }
 
 /*******************************************************************************
diff --git a/plat/arm/common/arm_sip_svc.c b/plat/arm/common/arm_sip_svc.c
index 3d308a3..c8f480f 100644
--- a/plat/arm/common/arm_sip_svc.c
+++ b/plat/arm/common/arm_sip_svc.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016-2018, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2016-2019, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -8,6 +8,7 @@
 
 #include <common/debug.h>
 #include <common/runtime_svc.h>
+#include <lib/debugfs.h>
 #include <lib/pmf/pmf.h>
 #include <plat/arm/common/arm_sip_svc.h>
 #include <plat/arm/common/plat_arm.h>
@@ -20,8 +21,18 @@
 
 static int arm_sip_setup(void)
 {
-	if (pmf_setup() != 0)
+	if (pmf_setup() != 0) {
 		return 1;
+	}
+
+#if USE_DEBUGFS
+
+	if (debugfs_smc_setup() != 0) {
+		return 1;
+	}
+
+#endif /* USE_DEBUGFS */
+
 	return 0;
 }
 
@@ -48,6 +59,15 @@
 				handle, flags);
 	}
 
+#if USE_DEBUGFS
+
+	if (is_debugfs_fid(smc_fid)) {
+		return debugfs_smc_handler(smc_fid, x1, x2, x3, x4, cookie,
+					   handle, flags);
+	}
+
+#endif /* USE_DEBUGFS */
+
 	switch (smc_fid) {
 	case ARM_SIP_SVC_EXE_STATE_SWITCH: {
 		u_register_t pc;