/*
 * Copyright 2015-2016 Freescale Semiconductor, Inc.
 * Copyright 2017 NXP
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * 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.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

/*
 * @file
 * Contains all the functions to handle parsing and loading of PE firmware
 * files.
 */
#include <linux/firmware.h>

#include "pfe_mod.h"
#include "pfe_firmware.h"
#include "pfe/pfe.h"

static struct elf32_shdr *get_elf_section_header(const struct firmware *fw,
						 const char *section)
{
	struct elf32_hdr *elf_hdr = (struct elf32_hdr *)fw->data;
	struct elf32_shdr *shdr;
	struct elf32_shdr *shdr_shstr;
	Elf32_Off e_shoff = be32_to_cpu(elf_hdr->e_shoff);
	Elf32_Half e_shentsize = be16_to_cpu(elf_hdr->e_shentsize);
	Elf32_Half e_shnum = be16_to_cpu(elf_hdr->e_shnum);
	Elf32_Half e_shstrndx = be16_to_cpu(elf_hdr->e_shstrndx);
	Elf32_Off shstr_offset;
	Elf32_Word sh_name;
	const char *name;
	int i;

	/* Section header strings */
	shdr_shstr = (struct elf32_shdr *)(fw->data + e_shoff + e_shstrndx *
					e_shentsize);
	shstr_offset = be32_to_cpu(shdr_shstr->sh_offset);

	for (i = 0; i < e_shnum; i++) {
		shdr = (struct elf32_shdr *)(fw->data + e_shoff
					     + i * e_shentsize);

		sh_name = be32_to_cpu(shdr->sh_name);

		name = (const char *)(fw->data + shstr_offset + sh_name);

		if (!strcmp(name, section))
			return shdr;
	}

	pr_err("%s: didn't find section %s\n", __func__, section);

	return NULL;
}

#if defined(CFG_DIAGS)
static int pfe_get_diags_info(const struct firmware *fw, struct pfe_diags_info
				*diags_info)
{
	struct elf32_shdr *shdr;
	unsigned long offset, size;

	shdr = get_elf_section_header(fw, ".pfe_diags_str");
	if (shdr) {
		offset = be32_to_cpu(shdr->sh_offset);
		size = be32_to_cpu(shdr->sh_size);
		diags_info->diags_str_base = be32_to_cpu(shdr->sh_addr);
		diags_info->diags_str_size = size;
		diags_info->diags_str_array = kmalloc(size, GFP_KERNEL);
		memcpy(diags_info->diags_str_array, fw->data + offset, size);

		return 0;
	} else {
		return -1;
	}
}
#endif

static void pfe_check_version_info(const struct firmware *fw)
{
	/*static char *version = NULL;*/
	static char *version;

	struct elf32_shdr *shdr = get_elf_section_header(fw, ".version");

	if (shdr) {
		if (!version) {
			/*
			 * this is the first fw we load, use its version
			 * string as reference (whatever it is)
			 */
			version = (char *)(fw->data +
					be32_to_cpu(shdr->sh_offset));

			pr_info("PFE binary version: %s\n", version);
		} else {
			/*
			 * already have loaded at least one firmware, check
			 * sequence can start now
			 */
			if (strcmp(version, (char *)(fw->data +
				be32_to_cpu(shdr->sh_offset)))) {
				pr_info(
				"WARNING: PFE firmware binaries from incompatible version\n");
			}
		}
	} else {
		/*
		 * version cannot be verified, a potential issue that should
		 * be reported
		 */
		pr_info(
			 "WARNING: PFE firmware binaries from incompatible version\n");
	}
}

/* PFE elf firmware loader.
 * Loads an elf firmware image into a list of PE's (specified using a bitmask)
 *
 * @param pe_mask	Mask of PE id's to load firmware to
 * @param fw		Pointer to the firmware image
 *
 * @return		0 on success, a negative value on error
 *
 */
int pfe_load_elf(int pe_mask, const struct firmware *fw, struct pfe *pfe)
{
	struct elf32_hdr *elf_hdr = (struct elf32_hdr *)fw->data;
	Elf32_Half sections = be16_to_cpu(elf_hdr->e_shnum);
	struct elf32_shdr *shdr = (struct elf32_shdr *)(fw->data +
					be32_to_cpu(elf_hdr->e_shoff));
	int id, section;
	int rc;

	pr_info("%s\n", __func__);

	/* Some sanity checks */
	if (strncmp(&elf_hdr->e_ident[EI_MAG0], ELFMAG, SELFMAG)) {
		pr_err("%s: incorrect elf magic number\n", __func__);
		return -EINVAL;
	}

	if (elf_hdr->e_ident[EI_CLASS] != ELFCLASS32) {
		pr_err("%s: incorrect elf class(%x)\n", __func__,
		       elf_hdr->e_ident[EI_CLASS]);
		return -EINVAL;
	}

	if (elf_hdr->e_ident[EI_DATA] != ELFDATA2MSB) {
		pr_err("%s: incorrect elf data(%x)\n", __func__,
		       elf_hdr->e_ident[EI_DATA]);
		return -EINVAL;
	}

	if (be16_to_cpu(elf_hdr->e_type) != ET_EXEC) {
		pr_err("%s: incorrect elf file type(%x)\n", __func__,
		       be16_to_cpu(elf_hdr->e_type));
		return -EINVAL;
	}

	for (section = 0; section < sections; section++, shdr++) {
		if (!(be32_to_cpu(shdr->sh_flags) & (SHF_WRITE | SHF_ALLOC |
			SHF_EXECINSTR)))
			continue;

		for (id = 0; id < MAX_PE; id++)
			if (pe_mask & (1 << id)) {
				rc = pe_load_elf_section(id, fw->data, shdr,
							 pfe->dev);
				if (rc < 0)
					goto err;
			}
	}

	pfe_check_version_info(fw);

	return 0;

err:
	return rc;
}

/* PFE firmware initialization.
 * Loads different firmware files from filesystem.
 * Initializes PE IMEM/DMEM and UTIL-PE DDR
 * Initializes control path symbol addresses (by looking them up in the elf
 * firmware files
 * Takes PE's out of reset
 *
 * @return	0 on success, a negative value on error
 *
 */
int pfe_firmware_init(struct pfe *pfe)
{
	const struct firmware *class_fw, *tmu_fw;
	int rc = 0;
#if !defined(CONFIG_FSL_PPFE_UTIL_DISABLED)
	const char *util_fw_name;
	const struct firmware *util_fw;
#endif

	pr_info("%s\n", __func__);

	if (request_firmware(&class_fw, CLASS_FIRMWARE_FILENAME, pfe->dev)) {
		pr_err("%s: request firmware %s failed\n", __func__,
		       CLASS_FIRMWARE_FILENAME);
		rc = -ETIMEDOUT;
		goto err0;
	}

	if (request_firmware(&tmu_fw, TMU_FIRMWARE_FILENAME, pfe->dev)) {
		pr_err("%s: request firmware %s failed\n", __func__,
		       TMU_FIRMWARE_FILENAME);
		rc = -ETIMEDOUT;
		goto err1;
}

#if !defined(CONFIG_FSL_PPFE_UTIL_DISABLED)
	util_fw_name = UTIL_FIRMWARE_FILENAME;

	if (request_firmware(&util_fw, util_fw_name, pfe->dev)) {
		pr_err("%s: request firmware %s failed\n", __func__,
		       util_fw_name);
		rc = -ETIMEDOUT;
		goto err2;
	}
#endif
	rc = pfe_load_elf(CLASS_MASK, class_fw, pfe);
	if (rc < 0) {
		pr_err("%s: class firmware load failed\n", __func__);
		goto err3;
	}

#if defined(CFG_DIAGS)
	rc = pfe_get_diags_info(class_fw, &pfe->diags.class_diags_info);
	if (rc < 0) {
		pr_warn(
			"PFE diags won't be available for class PEs\n");
		rc = 0;
	}
#endif

	rc = pfe_load_elf(TMU_MASK, tmu_fw, pfe);
	if (rc < 0) {
		pr_err("%s: tmu firmware load failed\n", __func__);
		goto err3;
	}

#if !defined(CONFIG_FSL_PPFE_UTIL_DISABLED)
	rc = pfe_load_elf(UTIL_MASK, util_fw, pfe);
	if (rc < 0) {
		pr_err("%s: util firmware load failed\n", __func__);
		goto err3;
	}

#if defined(CFG_DIAGS)
	rc = pfe_get_diags_info(util_fw, &pfe->diags.util_diags_info);
	if (rc < 0) {
		pr_warn(
			"PFE diags won't be available for util PE\n");
		rc = 0;
	}
#endif

	util_enable();
#endif

	tmu_enable(0xf);
	class_enable();

err3:
#if !defined(CONFIG_FSL_PPFE_UTIL_DISABLED)
	release_firmware(util_fw);

err2:
#endif
	release_firmware(tmu_fw);

err1:
	release_firmware(class_fw);

err0:
	return rc;
}

/* PFE firmware cleanup
 * Puts PE's in reset
 *
 *
 */
void pfe_firmware_exit(struct pfe *pfe)
{
	pr_info("%s\n", __func__);

	if (pe_reset_all(&pfe->ctrl) != 0)
		pr_err("Error: Failed to stop PEs, PFE reload may not work correctly\n");

	class_disable();
	tmu_disable(0xf);
#if !defined(CONFIG_FSL_PPFE_UTIL_DISABLED)
	util_disable();
#endif
}