130 lines
		
	
	
		
			3.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			130 lines
		
	
	
		
			3.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0-only
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| /*
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|  * Copyright (c) 2019-2020 Linaro Ltd.
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|  */
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| #include <linux/kernel.h>
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| #include <linux/module.h>
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| #include <linux/mutex.h>
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| #include <linux/of_address.h>
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| #include "qcom_pil_info.h"
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| 
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| /*
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|  * The PIL relocation information region is used to communicate memory regions
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|  * occupied by co-processor firmware for post mortem crash analysis.
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|  *
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|  * It consists of an array of entries with an 8 byte textual identifier of the
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|  * region followed by a 64 bit base address and 32 bit size, both little
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|  * endian.
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|  */
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| #define PIL_RELOC_NAME_LEN	8
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| #define PIL_RELOC_ENTRY_SIZE	(PIL_RELOC_NAME_LEN + sizeof(__le64) + sizeof(__le32))
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| 
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| struct pil_reloc {
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| 	void __iomem *base;
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| 	size_t num_entries;
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| };
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| 
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| static struct pil_reloc _reloc __read_mostly;
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| static DEFINE_MUTEX(pil_reloc_lock);
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| 
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| static int qcom_pil_info_init(void)
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| {
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| 	struct device_node *np;
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| 	struct resource imem;
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| 	void __iomem *base;
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| 	int ret;
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| 
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| 	/* Already initialized? */
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| 	if (_reloc.base)
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| 		return 0;
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| 
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| 	np = of_find_compatible_node(NULL, NULL, "qcom,pil-reloc-info");
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| 	if (!np)
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| 		return -ENOENT;
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| 
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| 	ret = of_address_to_resource(np, 0, &imem);
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| 	of_node_put(np);
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| 	if (ret < 0)
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| 		return ret;
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| 
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| 	base = ioremap(imem.start, resource_size(&imem));
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| 	if (!base) {
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| 		pr_err("failed to map PIL relocation info region\n");
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| 		return -ENOMEM;
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| 	}
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| 
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| 	memset_io(base, 0, resource_size(&imem));
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| 
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| 	_reloc.base = base;
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| 	_reloc.num_entries = (u32)resource_size(&imem) / PIL_RELOC_ENTRY_SIZE;
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| 
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| 	return 0;
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| }
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| 
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| /**
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|  * qcom_pil_info_store() - store PIL information of image in IMEM
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|  * @image:	name of the image
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|  * @base:	base address of the loaded image
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|  * @size:	size of the loaded image
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|  *
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|  * Return: 0 on success, negative errno on failure
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|  */
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| int qcom_pil_info_store(const char *image, phys_addr_t base, size_t size)
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| {
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| 	char buf[PIL_RELOC_NAME_LEN];
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| 	void __iomem *entry;
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| 	int ret;
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| 	int i;
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| 
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| 	mutex_lock(&pil_reloc_lock);
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| 	ret = qcom_pil_info_init();
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| 	if (ret < 0) {
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| 		mutex_unlock(&pil_reloc_lock);
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| 		return ret;
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| 	}
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| 
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| 	for (i = 0; i < _reloc.num_entries; i++) {
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| 		entry = _reloc.base + i * PIL_RELOC_ENTRY_SIZE;
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| 
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| 		memcpy_fromio(buf, entry, PIL_RELOC_NAME_LEN);
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| 
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| 		/*
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| 		 * An empty record means we didn't find it, given that the
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| 		 * records are packed.
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| 		 */
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| 		if (!buf[0])
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| 			goto found_unused;
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| 
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| 		if (!strncmp(buf, image, PIL_RELOC_NAME_LEN))
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| 			goto found_existing;
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| 	}
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| 
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| 	pr_warn("insufficient PIL info slots\n");
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| 	mutex_unlock(&pil_reloc_lock);
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| 	return -ENOMEM;
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| 
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| found_unused:
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| 	memcpy_toio(entry, image, strnlen(image, PIL_RELOC_NAME_LEN));
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| found_existing:
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| 	/* Use two writel() as base is only aligned to 4 bytes on odd entries */
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| 	writel(base, entry + PIL_RELOC_NAME_LEN);
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| 	writel((u64)base >> 32, entry + PIL_RELOC_NAME_LEN + 4);
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| 	writel(size, entry + PIL_RELOC_NAME_LEN + sizeof(__le64));
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| 	mutex_unlock(&pil_reloc_lock);
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| 
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| 	return 0;
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| }
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| EXPORT_SYMBOL_GPL(qcom_pil_info_store);
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| 
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| static void __exit pil_reloc_exit(void)
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| {
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| 	mutex_lock(&pil_reloc_lock);
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| 	iounmap(_reloc.base);
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| 	_reloc.base = NULL;
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| 	mutex_unlock(&pil_reloc_lock);
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| }
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| module_exit(pil_reloc_exit);
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| 
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| MODULE_DESCRIPTION("Qualcomm PIL relocation info");
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| MODULE_LICENSE("GPL v2");
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