juno: Add bootloader for SCP image

Signed-off-by: Jon Medhurst <tixy@linaro.org>

plat/juno/scp_bootloader.c

+/*
+ * Copyright (c) 2014, ARM Limited and Contributors. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * Redistributions of source code must retain the above copyright notice, this
+ * list of conditions and the following disclaimer.
+ *
+ * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * Neither the name of ARM nor the names of its contributors may be used
+ * to endorse or promote products derived from this software without specific
+ * prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <arch_helpers.h>
+#include <mhu.h>
+#include <platform.h>
+#include <scp_bootloader.h>
+#include <scpi.h>
+
+/* Boot commands sent from AP -> SCP */
+#define BOOT_CMD_START	0x01
+#define BOOT_CMD_DATA	0x02
+
+typedef struct {
+	uint32_t image_size;
+} cmd_start_payload;
+
+typedef struct {
+	uint32_t sequence_num;
+	uint32_t offset;
+	uint32_t size;
+} cmd_data_payload;
+
+#define BOOT_DATA_MAX_SIZE  0x1000
+
+/* Boot commands sent from SCP -> AP */
+#define BOOT_CMD_ACK	0x03
+#define BOOT_CMD_NACK	0x04
+
+typedef struct {
+	uint32_t sequence_num;
+} cmd_ack_payload;
+
+/*
+ * Unlike the runtime protocol, the boot protocol uses the same memory region
+ * for both AP -> SCP and SCP -> AP transfers; define the address of this...
+ */
+static void * const cmd_payload = (void *)(MHU_SECURE_BASE + 0x0080);
+
+static void *scp_boot_message_start(void)
+{
+	mhu_secure_message_start();
+
+	return cmd_payload;
+}
+
+static void scp_boot_message_send(unsigned command, size_t size)
+{
+	/* Make sure payload can be seen by SCP */
+	if (MHU_PAYLOAD_CACHED)
+		flush_dcache_range((unsigned long)cmd_payload, size);
+
+	/* Send command to SCP */
+	mhu_secure_message_send(command | (size << 8));
+}
+
+static uint32_t scp_boot_message_wait(size_t size)
+{
+	uint32_t response =  mhu_secure_message_wait();
+
+	/* Make sure we see the reply from the SCP and not any stale data */
+	if (MHU_PAYLOAD_CACHED)
+		inv_dcache_range((unsigned long)cmd_payload, size);
+
+	return response & 0xff;
+}
+
+static void scp_boot_message_end(void)
+{
+	mhu_secure_message_end();
+}
+
+static int transfer_block(uint32_t sequence_num, uint32_t offset, uint32_t size)
+{
+	cmd_data_payload *cmd_data = scp_boot_message_start();
+	cmd_data->sequence_num = sequence_num;
+	cmd_data->offset = offset;
+	cmd_data->size = size;
+
+	scp_boot_message_send(BOOT_CMD_DATA, sizeof(*cmd_data));
+
+	cmd_ack_payload *cmd_ack = cmd_payload;
+	int ok = scp_boot_message_wait(sizeof(*cmd_ack)) == BOOT_CMD_ACK
+		 && cmd_ack->sequence_num == sequence_num;
+
+	scp_boot_message_end();
+
+	return ok;
+}
+
+int scp_bootloader_transfer(void *image, unsigned int image_size)
+{
+	uintptr_t offset = (uintptr_t)image - MHU_SECURE_BASE;
+	uintptr_t end = offset + image_size;
+	uint32_t response;
+
+	mhu_secure_init();
+
+	/* Initiate communications with SCP */
+	do {
+		cmd_start_payload *cmd_start = scp_boot_message_start();
+		cmd_start->image_size = image_size;
+
+		scp_boot_message_send(BOOT_CMD_START, sizeof(*cmd_start));
+
+		response = scp_boot_message_wait(0);
+
+		scp_boot_message_end();
+	} while (response != BOOT_CMD_ACK);
+
+	/* Transfer image to SCP a block at a time */
+	uint32_t sequence_num = 1;
+	size_t size;
+	while ((size = end - offset) != 0) {
+		if (size > BOOT_DATA_MAX_SIZE)
+			size = BOOT_DATA_MAX_SIZE;
+		while (!transfer_block(sequence_num, offset, size))
+			; /* Retry forever */
+		offset += size;
+		sequence_num++;
+	}
+
+	/* Wait for SCP to signal it's ready */
+	return scpi_wait_ready();
+}

plat/juno/scp_bootloader.h

+/*
+ * Copyright (c) 2014, ARM Limited and Contributors. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * Redistributions of source code must retain the above copyright notice, this
+ * list of conditions and the following disclaimer.
+ *
+ * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * Neither the name of ARM nor the names of its contributors may be used
+ * to endorse or promote products derived from this software without specific
+ * prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef __SCP_BOOTLOADER_H__
+#define __SCP_BOOTLOADER_H__
+
+int scp_bootloader_transfer(void *image, unsigned int image_size);
+
+#endif