arm: meson: implement calls to secure monitor

Implement calls to secure monitor to read the MAC address from e-fuse.

Signed-off-by: Beniamino Galvani <b.galvani@gmail.com>

3 files changed, 59 insertions, 1 deletions

diff --git a/arch/arm/mach-meson/Makefile b/arch/arm/mach-meson/Makefile
index 44e3d63..bf49b8b 100644
--- a/arch/arm/mach-meson/Makefile
+++ b/arch/arm/mach-meson/Makefile
@@ -4,4 +4,4 @@
 # SPDX-License-Identifier:	GPL-2.0+
 #
 
-obj-y += board.o
+obj-y += board.o sm.o
diff --git a/arch/arm/mach-meson/board.c b/arch/arm/mach-meson/board.c
index 782f86c..64fa3c1 100644
--- a/arch/arm/mach-meson/board.c
+++ b/arch/arm/mach-meson/board.c
@@ -8,6 +8,7 @@
 #include <libfdt.h>
 #include <linux/err.h>
 #include <asm/arch/gxbb.h>
+#include <asm/arch/sm.h>
 #include <asm/armv8/mmu.h>
 #include <asm/unaligned.h>
 
diff --git a/arch/arm/mach-meson/sm.c b/arch/arm/mach-meson/sm.c
new file mode 100644
index 0000000..1b35a22
--- /dev/null
+++ b/arch/arm/mach-meson/sm.c
@@ -0,0 +1,57 @@
+/*
+ * (C) Copyright 2016 Beniamino Galvani <b.galvani@gmail.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ *
+ * Secure monitor calls.
+ */
+
+#include <common.h>
+#include <asm/arch/gxbb.h>
+#include <linux/kernel.h>
+
+#define FN_GET_SHARE_MEM_INPUT_BASE	0x82000020
+#define FN_GET_SHARE_MEM_OUTPUT_BASE	0x82000021
+#define FN_EFUSE_READ			0x82000030
+#define FN_EFUSE_WRITE			0x82000031
+
+static void *shmem_input;
+static void *shmem_output;
+
+static void meson_init_shmem(void)
+{
+	struct pt_regs regs;
+
+	if (shmem_input && shmem_output)
+		return;
+
+	regs.regs[0] = FN_GET_SHARE_MEM_INPUT_BASE;
+	smc_call(&regs);
+	shmem_input = (void *)regs.regs[0];
+
+	regs.regs[0] = FN_GET_SHARE_MEM_OUTPUT_BASE;
+	smc_call(&regs);
+	shmem_output = (void *)regs.regs[0];
+
+	debug("Secure Monitor shmem: 0x%p 0x%p\n", shmem_input, shmem_output);
+}
+
+ssize_t meson_sm_read_efuse(uintptr_t offset, void *buffer, size_t size)
+{
+	struct pt_regs regs;
+
+	meson_init_shmem();
+
+	regs.regs[0] = FN_EFUSE_READ;
+	regs.regs[1] = offset;
+	regs.regs[2] = size;
+
+	smc_call(&regs);
+
+	if (regs.regs[0] == 0)
+		return -1;
+
+	memcpy(buffer, shmem_output, min(size, regs.regs[0]));
+
+	return regs.regs[0];
+}