1 files changed, 221 insertions, 0 deletions
diff --git a/sound/soc/codecs/wcd-dsp-utils.c b/sound/soc/codecs/wcd-dsp-utils.c
new file mode 100644
index 000000000000..1f048917a6c8
--- /dev/null
+++ b/sound/soc/codecs/wcd-dsp-utils.c
@@ -0,0 +1,221 @@
+/*
+ * Copyright (c) 2016, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/firmware.h>
+#include <linux/elf.h>
+#include <linux/slab.h>
+#include <linux/list.h>
+#include "wcd-dsp-utils.h"
+
+static bool wdsp_is_valid_elf_hdr(const struct elf32_hdr *ehdr,
+				  size_t fw_size)
+{
+	if (fw_size < sizeof(*ehdr)) {
+		pr_err("%s: Firmware too small\n", __func__);
+		goto elf_check_fail;
+	}
+
+	if (memcmp(ehdr->e_ident, ELFMAG, SELFMAG) != 0) {
+		pr_err("%s: Not an ELF file\n", __func__);
+		goto elf_check_fail;
+	}
+
+	if (ehdr->e_type != ET_EXEC && ehdr->e_type != ET_DYN) {
+		pr_err("%s: Not an executable image\n", __func__);
+		goto elf_check_fail;
+	}
+
+	if (ehdr->e_phnum == 0) {
+		pr_err("%s: no segments to load\n", __func__);
+		goto elf_check_fail;
+	}
+
+	if (sizeof(struct elf32_phdr) * ehdr->e_phnum +
+	    sizeof(struct elf32_hdr) > fw_size) {
+		pr_err("%s: Too small MDT file\n", __func__);
+		goto elf_check_fail;
+	}
+
+	return true;
+
+elf_check_fail:
+	return false;
+}
+
+static int wdsp_add_segment_to_list(struct device *dev,
+				    const char *img_fname,
+				    const struct elf32_phdr *phdr,
+				    int phdr_idx,
+				    struct list_head *seg_list)
+{
+	struct wdsp_img_segment *seg;
+	int ret = 0;
+
+	/* Do not load segments with zero size */
+	if (phdr->p_filesz == 0 || phdr->p_memsz == 0)
+		goto done;
+
+	seg = kzalloc(sizeof(*seg), GFP_KERNEL);
+	if (!seg) {
+		ret = -ENOMEM;
+		goto done;
+	}
+
+	snprintf(seg->split_fname, sizeof(seg->split_fname),
+		 "%s.b%02d", img_fname, phdr_idx);
+	ret = request_firmware(&seg->split_fw, seg->split_fname, dev);
+	if (IS_ERR_VALUE(ret)) {
+		dev_err(dev, "%s: firmware %s not found\n",
+			__func__, seg->split_fname);
+		goto bad_seg;
+	}
+
+	seg->load_addr = phdr->p_paddr;
+	seg->size = phdr->p_filesz;
+	seg->data = (u8 *) seg->split_fw->data;
+
+	list_add_tail(&seg->list, seg_list);
+done:
+	return ret;
+bad_seg:
+	kfree(seg);
+	return ret;
+}
+
+/*
+ * wdsp_flush_segment_list: Flush the list of segments
+ * @seg_list: List of segments to be flushed
+ * This API will traverse through the list of segments provided in
+ * seg_list, release the firmware for each segment and delete the
+ * segment from the list.
+ */
+void wdsp_flush_segment_list(struct list_head *seg_list)
+{
+	struct wdsp_img_segment *seg, *next;
+
+	list_for_each_entry_safe(seg, next, seg_list, list) {
+		release_firmware(seg->split_fw);
+		list_del(&seg->list);
+		kfree(seg);
+	}
+}
+EXPORT_SYMBOL(wdsp_flush_segment_list);
+
+/*
+ * wdsp_get_segment_list: Get the list of requested segments
+ * @dev: struct device pointer of caller
+ * @img_fname: Image name for the mdt and split firmware files
+ * @segment_type: Requested segment type, should be either
+ *		  WDSP_ELF_FLAG_RE or WDSP_ELF_FLAG_WRITE
+ * @seg_list: An initialized head for list of segmented to be returned
+ * @entry_point: Pointer to return the entry point of the image
+ * This API will parse the mdt file for img_fname and create
+ * an struct wdsp_img_segment for each segment that matches segment_type
+ * and add this structure to list pointed by seg_list
+ */
+int wdsp_get_segment_list(struct device *dev,
+			  const char *img_fname,
+			  unsigned int segment_type,
+			  struct list_head *seg_list,
+			  u32 *entry_point)
+{
+	const struct firmware *fw;
+	const struct elf32_hdr *ehdr;
+	const struct elf32_phdr *phdr;
+	const u8 *elf_ptr;
+	char mdt_name[WDSP_IMG_NAME_LEN_MAX];
+	int ret, phdr_idx;
+	bool segment_match;
+
+	if (!dev) {
+		ret = -EINVAL;
+		pr_err("%s: Invalid device handle\n", __func__);
+		goto done;
+	}
+
+	if (!img_fname || !seg_list || !entry_point) {
+		ret = -EINVAL;
+		dev_err(dev, "%s: Invalid input params\n",
+			__func__);
+		goto done;
+	}
+
+	if (segment_type != WDSP_ELF_FLAG_RE &&
+	    segment_type != WDSP_ELF_FLAG_WRITE) {
+		dev_err(dev, "%s: Invalid request for segment_type %d\n",
+			__func__, segment_type);
+		ret = -EINVAL;
+		goto done;
+	}
+
+	snprintf(mdt_name, sizeof(mdt_name), "%s.mdt", img_fname);
+	ret = request_firmware(&fw, mdt_name, dev);
+	if (IS_ERR_VALUE(ret)) {
+		dev_err(dev, "%s: firmware %s not found\n",
+			__func__, mdt_name);
+		goto done;
+	}
+
+	ehdr = (struct elf32_hdr *) fw->data;
+	*entry_point = ehdr->e_entry;
+	if (!wdsp_is_valid_elf_hdr(ehdr, fw->size)) {
+		dev_err(dev, "%s: fw mdt %s is invalid\n",
+			__func__, mdt_name);
+		ret = -EINVAL;
+		goto bad_elf;
+	}
+
+	elf_ptr = fw->data + sizeof(*ehdr);
+	for (phdr_idx = 0; phdr_idx < ehdr->e_phnum; phdr_idx++) {
+		phdr = (struct elf32_phdr *) elf_ptr;
+		segment_match = false;
+
+		switch (segment_type) {
+		case WDSP_ELF_FLAG_RE:
+			/*
+			 * Flag can be READ or EXECUTE or both but
+			 * WRITE flag should not be set.
+			 */
+			if ((phdr->p_flags & segment_type) &&
+			    !(phdr->p_flags & WDSP_ELF_FLAG_WRITE))
+				segment_match = true;
+			break;
+		case WDSP_ELF_FLAG_WRITE:
+			/*
+			 * If WRITE flag is set, other flags do not
+			 * matter.
+			 */
+			if (phdr->p_flags & segment_type)
+				segment_match = true;
+			break;
+		}
+
+		if (segment_match) {
+			ret = wdsp_add_segment_to_list(dev, img_fname, phdr,
+						       phdr_idx, seg_list);
+			if (IS_ERR_VALUE(ret)) {
+				wdsp_flush_segment_list(seg_list);
+				goto bad_elf;
+			}
+		}
+		elf_ptr = elf_ptr + sizeof(*phdr);
+	}
+
+bad_elf:
+	release_firmware(fw);
+done:
+	return ret;
+}
+EXPORT_SYMBOL(wdsp_get_segment_list);