From 5777b2cd18535dc4646314d309721dd5285742ba Mon Sep 17 00:00:00 2001
From: Siddharth Gupta <sidgup@codeaurora.org>
Date: Tue, 15 Dec 2020 17:49:59 -0800
Subject: [PATCH] soc: qcom: mdt_loader: Read hash from firmware blob

Since the split elf blobs will always contain the hash segment, we rely on
the blob file to get the hash rather than assume that it will be present in
the mdt file. This change uses the hash index to read the appropriate elf
blob to get the hash segment.

Change-Id: Iaf37a15f7794d417d01d9eda4a9df772623ae19c
Signed-off-by: Siddharth Gupta <sidgup@codeaurora.org>
---
 drivers/remoteproc/qcom_q6v5_mss.c  |  4 +--
 drivers/soc/qcom/mdt_loader.c       | 38 +++++++++++++++++++++--------
 include/linux/soc/qcom/mdt_loader.h |  3 ++-
 3 files changed, 32 insertions(+), 13 deletions(-)

diff --git a/drivers/remoteproc/qcom_q6v5_mss.c b/drivers/remoteproc/qcom_q6v5_mss.c
index 49faa90da93f..605cdc3c7bac 100644
--- a/drivers/remoteproc/qcom_q6v5_mss.c
+++ b/drivers/remoteproc/qcom_q6v5_mss.c
@@ -4,7 +4,7 @@
  *
  * Copyright (C) 2016 Linaro Ltd.
  * Copyright (C) 2014 Sony Mobile Communications AB
- * Copyright (c) 2012-2013, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2012-2013, 2020 The Linux Foundation. All rights reserved.
  */
 
 #include <linux/clk.h>
@@ -679,7 +679,7 @@ static int q6v5_mpss_init_image(struct q6v5 *qproc, const struct firmware *fw)
 	void *ptr;
 	int ret;
 
-	metadata = qcom_mdt_read_metadata(fw, &size);
+	metadata = qcom_mdt_read_metadata(qproc->dev, fw, qproc->hexagon_mdt_image, &size);
 	if (IS_ERR(metadata))
 		return PTR_ERR(metadata);
 
diff --git a/drivers/soc/qcom/mdt_loader.c b/drivers/soc/qcom/mdt_loader.c
index cb5cdd0e5f49..0d528b08663b 100644
--- a/drivers/soc/qcom/mdt_loader.c
+++ b/drivers/soc/qcom/mdt_loader.c
@@ -103,15 +103,18 @@ EXPORT_SYMBOL_GPL(qcom_mdt_get_size);
  *
  * Return: pointer to data, or ERR_PTR()
  */
-void *qcom_mdt_read_metadata(const struct firmware *fw, size_t *data_len)
+void *qcom_mdt_read_metadata(struct device *dev, const struct firmware *fw, const char *firmware,
+			     size_t *data_len)
 {
 	const struct elf32_phdr *phdrs;
 	const struct elf32_hdr *ehdr;
-	size_t hash_offset;
+	const struct firmware *seg_fw;
 	size_t hash_index;
 	size_t hash_size;
 	size_t ehdr_size;
+	char *fw_name;
 	void *data;
+	int ret;
 
 	if (fw->size < sizeof(struct elf32_hdr)) {
 		dev_err(dev, "Image is too small\n");
@@ -147,14 +150,29 @@ void *qcom_mdt_read_metadata(const struct firmware *fw, size_t *data_len)
 	if (!data)
 		return ERR_PTR(-ENOMEM);
 
-	/* Is the header and hash already packed */
-	if (qcom_mdt_bins_are_split(fw))
-		hash_offset = phdrs[0].p_filesz;
-	else
-		hash_offset = phdrs[hash_index].p_offset;
-
+	/* copy elf header */
 	memcpy(data, fw->data, ehdr_size);
-	memcpy(data + ehdr_size, fw->data + hash_offset, hash_size);
+
+	if (qcom_mdt_bins_are_split(fw)) {
+		fw_name = kstrdup(firmware, GFP_KERNEL);
+		if (!fw_name) {
+			kfree(data);
+			return ERR_PTR(-ENOMEM);
+		}
+		snprintf(fw_name + strlen(fw_name) - 3, 4, "b%02d", hash_index);
+
+		ret = request_firmware_into_buf(&seg_fw, fw_name, dev, data + ehdr_size, hash_size);
+		kfree(fw_name);
+
+		if (ret) {
+			kfree(data);
+			return ERR_PTR(ret);
+		}
+
+		release_firmware(seg_fw);
+	} else {
+		memcpy(data + ehdr_size, fw->data + phdrs[hash_index].p_offset, hash_size);
+	}
 
 	*data_len = ehdr_size + hash_size;
 
@@ -201,7 +219,7 @@ static int __qcom_mdt_load(struct device *dev, const struct firmware *fw,
 		return -ENOMEM;
 
 	if (pas_init) {
-		metadata = qcom_mdt_read_metadata(fw, &metadata_len);
+		metadata = qcom_mdt_read_metadata(dev, fw, firmware, &metadata_len);
 		if (IS_ERR(metadata)) {
 			ret = PTR_ERR(metadata);
 			goto out;
diff --git a/include/linux/soc/qcom/mdt_loader.h b/include/linux/soc/qcom/mdt_loader.h
index e600baec6825..04ba5e8ef8ac 100644
--- a/include/linux/soc/qcom/mdt_loader.h
+++ b/include/linux/soc/qcom/mdt_loader.h
@@ -21,6 +21,7 @@ int qcom_mdt_load_no_init(struct device *dev, const struct firmware *fw,
 			  const char *fw_name, int pas_id, void *mem_region,
 			  phys_addr_t mem_phys, size_t mem_size,
 			  phys_addr_t *reloc_base);
-void *qcom_mdt_read_metadata(const struct firmware *fw, size_t *data_len);
+void *qcom_mdt_read_metadata(struct device *dev, const struct firmware *fw, const char *firmware,
+			     size_t *data_len);
 
 #endif