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  • /*
     * Copyright (c) 2011 The Chromium OS Authors.
    
     * SPDX-License-Identifier:	GPL-2.0+
    
    #ifndef USE_HOSTCC
    
    #include <common.h>
    
    #include <serial.h>
    #include <libfdt.h>
    #include <fdtdec.h>
    
    #include <asm/sections.h>
    
    #include <linux/ctype.h>
    
    
    DECLARE_GLOBAL_DATA_PTR;
    
    /*
     * Here are the type we know about. One day we might allow drivers to
     * register. For now we just put them here. The COMPAT macro allows us to
     * turn this into a sparse list later, and keeps the ID with the name.
     */
    #define COMPAT(id, name) name
    static const char * const compat_names[COMPAT_COUNT] = {
    
    	COMPAT(UNKNOWN, "<none>"),
    
    	COMPAT(NVIDIA_TEGRA20_EMC, "nvidia,tegra20-emc"),
    	COMPAT(NVIDIA_TEGRA20_EMC_TABLE, "nvidia,tegra20-emc-table"),
    
    	COMPAT(NVIDIA_TEGRA20_KBC, "nvidia,tegra20-kbc"),
    
    	COMPAT(NVIDIA_TEGRA20_NAND, "nvidia,tegra20-nand"),
    
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    	COMPAT(NVIDIA_TEGRA20_PWM, "nvidia,tegra20-pwm"),
    
    	COMPAT(NVIDIA_TEGRA124_DC, "nvidia,tegra124-dc"),
    	COMPAT(NVIDIA_TEGRA124_SOR, "nvidia,tegra124-sor"),
    	COMPAT(NVIDIA_TEGRA124_PMC, "nvidia,tegra124-pmc"),
    
    	COMPAT(NVIDIA_TEGRA20_DC, "nvidia,tegra20-dc"),
    
    	COMPAT(NVIDIA_TEGRA124_SDMMC, "nvidia,tegra124-sdhci"),
    
    	COMPAT(NVIDIA_TEGRA30_SDMMC, "nvidia,tegra30-sdhci"),
    
    	COMPAT(NVIDIA_TEGRA20_SDMMC, "nvidia,tegra20-sdhci"),
    
    	COMPAT(NVIDIA_TEGRA124_PCIE, "nvidia,tegra124-pcie"),
    	COMPAT(NVIDIA_TEGRA30_PCIE, "nvidia,tegra30-pcie"),
    	COMPAT(NVIDIA_TEGRA20_PCIE, "nvidia,tegra20-pcie"),
    
    	COMPAT(NVIDIA_TEGRA124_XUSB_PADCTL, "nvidia,tegra124-xusb-padctl"),
    
    	COMPAT(SMSC_LAN9215, "smsc,lan9215"),
    	COMPAT(SAMSUNG_EXYNOS5_SROMC, "samsung,exynos-sromc"),
    
    	COMPAT(SAMSUNG_S3C2440_I2C, "samsung,s3c2440-i2c"),
    
    	COMPAT(SAMSUNG_EXYNOS5_SOUND, "samsung,exynos-sound"),
    	COMPAT(WOLFSON_WM8994_CODEC, "wolfson,wm8994-codec"),
    
    	COMPAT(GOOGLE_CROS_EC_KEYB, "google,cros-ec-keyb"),
    
    	COMPAT(SAMSUNG_EXYNOS_USB_PHY, "samsung,exynos-usb-phy"),
    
    	COMPAT(SAMSUNG_EXYNOS5_USB3_PHY, "samsung,exynos5250-usb3-phy"),
    
    	COMPAT(SAMSUNG_EXYNOS_TMU, "samsung,exynos-tmu"),
    
    	COMPAT(SAMSUNG_EXYNOS_FIMD, "samsung,exynos-fimd"),
    
    	COMPAT(SAMSUNG_EXYNOS_MIPI_DSI, "samsung,exynos-mipi-dsi"),
    
    	COMPAT(SAMSUNG_EXYNOS5_DP, "samsung,exynos5-dp"),
    
    	COMPAT(SAMSUNG_EXYNOS_DWMMC, "samsung,exynos-dwmmc"),
    
    	COMPAT(SAMSUNG_EXYNOS_MMC, "samsung,exynos-mmc"),
    
    	COMPAT(SAMSUNG_EXYNOS_SERIAL, "samsung,exynos4210-uart"),
    
    	COMPAT(MAXIM_MAX77686_PMIC, "maxim,max77686"),
    
    	COMPAT(GENERIC_SPI_FLASH, "spi-flash"),
    
    	COMPAT(MAXIM_98095_CODEC, "maxim,max98095-codec"),
    
    	COMPAT(INFINEON_SLB9635_TPM, "infineon,slb9635-tpm"),
    
    	COMPAT(INFINEON_SLB9645_TPM, "infineon,slb9645tt"),
    
    	COMPAT(SAMSUNG_EXYNOS5_I2C, "samsung,exynos5-hsi2c"),
    
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    	COMPAT(SANDBOX_LCD_SDL, "sandbox,lcd-sdl"),
    
    	COMPAT(TI_TPS65090, "ti,tps65090"),
    
    	COMPAT(COMPAT_NXP_PTN3460, "nxp,ptn3460"),
    
    	COMPAT(SAMSUNG_EXYNOS_SYSMMU, "samsung,sysmmu-v3.3"),
    
    	COMPAT(PARADE_PS8625, "parade,ps8625"),
    
    	COMPAT(INTEL_MICROCODE, "intel,microcode"),
    
    	COMPAT(MEMORY_SPD, "memory-spd"),
    
    	COMPAT(INTEL_PANTHERPOINT_AHCI, "intel,pantherpoint-ahci"),
    
    	COMPAT(INTEL_MODEL_206AX, "intel,model-206ax"),
    
    	COMPAT(INTEL_GMA, "intel,gma"),
    
    	COMPAT(AMS_AS3722, "ams,as3722"),
    
    	COMPAT(INTEL_ICH_SPI, "intel,ich-spi"),
    
    	COMPAT(INTEL_QRK_MRC, "intel,quark-mrc"),
    
    	COMPAT(INTEL_X86_PINCTRL, "intel,x86-pinctrl"),
    
    	COMPAT(SOCIONEXT_XHCI, "socionext,uniphier-xhci"),
    
    	COMPAT(COMPAT_INTEL_PCH, "intel,bd82x6x"),
    
    	COMPAT(COMPAT_INTEL_IRQ_ROUTER, "intel,irq-router"),
    
    const char *fdtdec_get_compatible(enum fdt_compat_id id)
    {
    	/* We allow reading of the 'unknown' ID for testing purposes */
    	assert(id >= 0 && id < COMPAT_COUNT);
    	return compat_names[id];
    }
    
    
    fdt_addr_t fdtdec_get_addr_size(const void *blob, int node,
    		const char *prop_name, fdt_size_t *sizep)
    
    {
    	const fdt_addr_t *cell;
    	int len;
    
    
    	debug("%s: %s: ", __func__, prop_name);
    
    	cell = fdt_getprop(blob, node, prop_name, &len);
    
    	if (cell && ((!sizep && len == sizeof(fdt_addr_t)) ||
    		     len == sizeof(fdt_addr_t) * 2)) {
    
    		fdt_addr_t addr = fdt_addr_to_cpu(*cell);
    
    		if (sizep) {
    			const fdt_size_t *size;
    
    			size = (fdt_size_t *)((char *)cell +
    					sizeof(fdt_addr_t));
    			*sizep = fdt_size_to_cpu(*size);
    
    			debug("addr=%08lx, size=%llx\n",
    			      (ulong)addr, (u64)*sizep);
    
    			debug("%08lx\n", (ulong)addr);
    
    		return addr;
    	}
    	debug("(not found)\n");
    
    	return FDT_ADDR_T_NONE;
    }
    
    
    fdt_addr_t fdtdec_get_addr(const void *blob, int node,
    		const char *prop_name)
    {
    	return fdtdec_get_addr_size(blob, node, prop_name, NULL);
    }
    
    
    #ifdef CONFIG_PCI
    int fdtdec_get_pci_addr(const void *blob, int node, enum fdt_pci_space type,
    		const char *prop_name, struct fdt_pci_addr *addr)
    {
    	const u32 *cell;
    	int len;
    	int ret = -ENOENT;
    
    	debug("%s: %s: ", __func__, prop_name);
    
    	/*
    	 * If we follow the pci bus bindings strictly, we should check
    	 * the value of the node's parent node's #address-cells and
    	 * #size-cells. They need to be 3 and 2 accordingly. However,
    	 * for simplicity we skip the check here.
    	 */
    	cell = fdt_getprop(blob, node, prop_name, &len);
    	if (!cell)
    		goto fail;
    
    	if ((len % FDT_PCI_REG_SIZE) == 0) {
    		int num = len / FDT_PCI_REG_SIZE;
    		int i;
    
    		for (i = 0; i < num; i++) {
    			debug("pci address #%d: %08lx %08lx %08lx\n", i,
    			      (ulong)fdt_addr_to_cpu(cell[0]),
    			      (ulong)fdt_addr_to_cpu(cell[1]),
    			      (ulong)fdt_addr_to_cpu(cell[2]));
    			if ((fdt_addr_to_cpu(*cell) & type) == type) {
    				addr->phys_hi = fdt_addr_to_cpu(cell[0]);
    				addr->phys_mid = fdt_addr_to_cpu(cell[1]);
    				addr->phys_lo = fdt_addr_to_cpu(cell[2]);
    				break;
    			} else {
    				cell += (FDT_PCI_ADDR_CELLS +
    					 FDT_PCI_SIZE_CELLS);
    			}
    		}
    
    
    		if (i == num) {
    			ret = -ENXIO;
    
    
    		return 0;
    	} else {
    		ret = -EINVAL;
    	}
    
    fail:
    	debug("(not found)\n");
    	return ret;
    }
    
    int fdtdec_get_pci_vendev(const void *blob, int node, u16 *vendor, u16 *device)
    {
    	const char *list, *end;
    	int len;
    
    	list = fdt_getprop(blob, node, "compatible", &len);
    	if (!list)
    		return -ENOENT;
    
    	end = list + len;
    	while (list < end) {
    		char *s;
    
    		len = strlen(list);
    		if (len >= strlen("pciVVVV,DDDD")) {
    			s = strstr(list, "pci");
    
    			/*
    			 * check if the string is something like pciVVVV,DDDD.RR
    			 * or just pciVVVV,DDDD
    			 */
    			if (s && s[7] == ',' &&
    			    (s[12] == '.' || s[12] == 0)) {
    				s += 3;
    				*vendor = simple_strtol(s, NULL, 16);
    
    				s += 5;
    				*device = simple_strtol(s, NULL, 16);
    
    				return 0;
    			}
    		} else {
    			list += (len + 1);
    		}
    	}
    
    	return -ENOENT;
    }
    
    int fdtdec_get_pci_bdf(const void *blob, int node,
    		struct fdt_pci_addr *addr, pci_dev_t *bdf)
    {
    	u16 dt_vendor, dt_device, vendor, device;
    	int ret;
    
    	/* get vendor id & device id from the compatible string */
    	ret = fdtdec_get_pci_vendev(blob, node, &dt_vendor, &dt_device);
    	if (ret)
    		return ret;
    
    	/* extract the bdf from fdt_pci_addr */
    	*bdf = addr->phys_hi & 0xffff00;
    
    	/* read vendor id & device id based on bdf */
    	pci_read_config_word(*bdf, PCI_VENDOR_ID, &vendor);
    	pci_read_config_word(*bdf, PCI_DEVICE_ID, &device);
    
    	/*
    	 * Note there are two places in the device tree to fully describe
    	 * a pci device: one is via compatible string with a format of
    	 * "pciVVVV,DDDD" and the other one is the bdf numbers encoded in
    	 * the device node's reg address property. We read the vendor id
    	 * and device id based on bdf and compare the values with the
    	 * "VVVV,DDDD". If they are the same, then we are good to use bdf
    	 * to read device's bar. But if they are different, we have to rely
    	 * on the vendor id and device id extracted from the compatible
    	 * string and locate the real bdf by pci_find_device(). This is
    	 * because normally we may only know device's device number and
    	 * function number when writing device tree. The bus number is
    	 * dynamically assigned during the pci enumeration process.
    	 */
    	if ((dt_vendor != vendor) || (dt_device != device)) {
    		*bdf = pci_find_device(dt_vendor, dt_device, 0);
    		if (*bdf == -1)
    			return -ENODEV;
    	}
    
    	return 0;
    }
    
    int fdtdec_get_pci_bar32(const void *blob, int node,
    		struct fdt_pci_addr *addr, u32 *bar)
    {
    	pci_dev_t bdf;
    	int barnum;
    	int ret;
    
    	/* get pci devices's bdf */
    	ret = fdtdec_get_pci_bdf(blob, node, addr, &bdf);
    	if (ret)
    		return ret;
    
    	/* extract the bar number from fdt_pci_addr */
    	barnum = addr->phys_hi & 0xff;
    	if ((barnum < PCI_BASE_ADDRESS_0) || (barnum > PCI_CARDBUS_CIS))
    		return -EINVAL;
    
    	barnum = (barnum - PCI_BASE_ADDRESS_0) / 4;
    	*bar = pci_read_bar32(pci_bus_to_hose(PCI_BUS(bdf)), bdf, barnum);
    
    	return 0;
    }
    #endif
    
    
    uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name,
    		uint64_t default_val)
    {
    	const uint64_t *cell64;
    	int length;
    
    	cell64 = fdt_getprop(blob, node, prop_name, &length);
    	if (!cell64 || length < sizeof(*cell64))
    		return default_val;
    
    	return fdt64_to_cpu(*cell64);
    }
    
    
    int fdtdec_get_is_enabled(const void *blob, int node)
    
    {
    	const char *cell;
    
    
    	/*
    	 * It should say "okay", so only allow that. Some fdts use "ok" but
    	 * this is a bug. Please fix your device tree source file. See here
    	 * for discussion:
    	 *
    	 * http://www.mail-archive.com/u-boot@lists.denx.de/msg71598.html
    	 */
    
    	cell = fdt_getprop(blob, node, "status", NULL);
    	if (cell)
    
    		return 0 == strcmp(cell, "okay");
    	return 1;
    
    enum fdt_compat_id fdtdec_lookup(const void *blob, int node)
    
    {
    	enum fdt_compat_id id;
    
    	/* Search our drivers */
    	for (id = COMPAT_UNKNOWN; id < COMPAT_COUNT; id++)
    		if (0 == fdt_node_check_compatible(blob, node,
    				compat_names[id]))
    			return id;
    	return COMPAT_UNKNOWN;
    }
    
    int fdtdec_next_compatible(const void *blob, int node,
    		enum fdt_compat_id id)
    {
    	return fdt_node_offset_by_compatible(blob, node, compat_names[id]);
    }
    
    
    int fdtdec_next_compatible_subnode(const void *blob, int node,
    		enum fdt_compat_id id, int *depthp)
    {
    	do {
    		node = fdt_next_node(blob, node, depthp);
    	} while (*depthp > 1);
    
    	/* If this is a direct subnode, and compatible, return it */
    	if (*depthp == 1 && 0 == fdt_node_check_compatible(
    						blob, node, compat_names[id]))
    		return node;
    
    	return -FDT_ERR_NOTFOUND;
    }
    
    
    int fdtdec_next_alias(const void *blob, const char *name,
    		enum fdt_compat_id id, int *upto)
    {
    #define MAX_STR_LEN 20
    	char str[MAX_STR_LEN + 20];
    	int node, err;
    
    	/* snprintf() is not available */
    	assert(strlen(name) < MAX_STR_LEN);
    	sprintf(str, "%.*s%d", MAX_STR_LEN, name, *upto);
    
    	node = fdt_path_offset(blob, str);
    
    	if (node < 0)
    		return node;
    	err = fdt_node_check_compatible(blob, node, compat_names[id]);
    	if (err < 0)
    		return err;
    
    	if (err)
    		return -FDT_ERR_NOTFOUND;
    	(*upto)++;
    	return node;
    
    int fdtdec_find_aliases_for_id(const void *blob, const char *name,
    			enum fdt_compat_id id, int *node_list, int maxcount)
    
    {
    	memset(node_list, '\0', sizeof(*node_list) * maxcount);
    
    	return fdtdec_add_aliases_for_id(blob, name, id, node_list, maxcount);
    }
    
    /* TODO: Can we tighten this code up a little? */
    int fdtdec_add_aliases_for_id(const void *blob, const char *name,
    			enum fdt_compat_id id, int *node_list, int maxcount)
    
    {
    	int name_len = strlen(name);
    	int nodes[maxcount];
    	int num_found = 0;
    	int offset, node;
    	int alias_node;
    	int count;
    	int i, j;
    
    	/* find the alias node if present */
    	alias_node = fdt_path_offset(blob, "/aliases");
    
    	/*
    	 * start with nothing, and we can assume that the root node can't
    	 * match
    	 */
    	memset(nodes, '\0', sizeof(nodes));
    
    	/* First find all the compatible nodes */
    	for (node = count = 0; node >= 0 && count < maxcount;) {
    		node = fdtdec_next_compatible(blob, node, id);
    		if (node >= 0)
    			nodes[count++] = node;
    	}
    	if (node >= 0)
    		debug("%s: warning: maxcount exceeded with alias '%s'\n",
    		       __func__, name);
    
    	/* Now find all the aliases */
    	for (offset = fdt_first_property_offset(blob, alias_node);
    			offset > 0;
    			offset = fdt_next_property_offset(blob, offset)) {
    		const struct fdt_property *prop;
    		const char *path;
    		int number;
    		int found;
    
    		node = 0;
    		prop = fdt_get_property_by_offset(blob, offset, NULL);
    		path = fdt_string(blob, fdt32_to_cpu(prop->nameoff));
    		if (prop->len && 0 == strncmp(path, name, name_len))
    			node = fdt_path_offset(blob, prop->data);
    		if (node <= 0)
    			continue;
    
    		/* Get the alias number */
    		number = simple_strtoul(path + name_len, NULL, 10);
    		if (number < 0 || number >= maxcount) {
    			debug("%s: warning: alias '%s' is out of range\n",
    			       __func__, path);
    			continue;
    		}
    
    		/* Make sure the node we found is actually in our list! */
    		found = -1;
    		for (j = 0; j < count; j++)
    			if (nodes[j] == node) {
    				found = j;
    				break;
    			}
    
    		if (found == -1) {
    			debug("%s: warning: alias '%s' points to a node "
    				"'%s' that is missing or is not compatible "
    				" with '%s'\n", __func__, path,
    				fdt_get_name(blob, node, NULL),
    			       compat_names[id]);
    			continue;
    		}
    
    		/*
    		 * Add this node to our list in the right place, and mark
    		 * it as done.
    		 */
    		if (fdtdec_get_is_enabled(blob, node)) {
    
    			if (node_list[number]) {
    				debug("%s: warning: alias '%s' requires that "
    				      "a node be placed in the list in a "
    				      "position which is already filled by "
    				      "node '%s'\n", __func__, path,
    				      fdt_get_name(blob, node, NULL));
    				continue;
    			}
    
    			node_list[number] = node;
    			if (number >= num_found)
    				num_found = number + 1;
    		}
    
    	}
    
    	/* Add any nodes not mentioned by an alias */
    	for (i = j = 0; i < maxcount; i++) {
    		if (!node_list[i]) {
    			for (; j < maxcount; j++)
    				if (nodes[j] &&
    					fdtdec_get_is_enabled(blob, nodes[j]))
    					break;
    
    			/* Have we run out of nodes to add? */
    			if (j == maxcount)
    				break;
    
    			assert(!node_list[i]);
    			node_list[i] = nodes[j++];
    			if (i >= num_found)
    				num_found = i + 1;
    		}
    	}
    
    	return num_found;
    }
    
    
    int fdtdec_get_alias_seq(const void *blob, const char *base, int offset,
    			 int *seqp)
    {
    	int base_len = strlen(base);
    	const char *find_name;
    	int find_namelen;
    	int prop_offset;
    	int aliases;
    
    	find_name = fdt_get_name(blob, offset, &find_namelen);
    	debug("Looking for '%s' at %d, name %s\n", base, offset, find_name);
    
    	aliases = fdt_path_offset(blob, "/aliases");
    	for (prop_offset = fdt_first_property_offset(blob, aliases);
    	     prop_offset > 0;
    	     prop_offset = fdt_next_property_offset(blob, prop_offset)) {
    		const char *prop;
    		const char *name;
    		const char *slash;
    
    
    		prop = fdt_getprop_by_offset(blob, prop_offset, &name, &len);
    		debug("   - %s, %s\n", name, prop);
    		if (len < find_namelen || *prop != '/' || prop[len - 1] ||
    		    strncmp(name, base, base_len))
    			continue;
    
    		slash = strrchr(prop, '/');
    		if (strcmp(slash + 1, find_name))
    			continue;
    
    		val = trailing_strtol(name);
    		if (val != -1) {
    			*seqp = val;
    			debug("Found seq %d\n", *seqp);
    			return 0;
    
    int fdtdec_get_chosen_node(const void *blob, const char *name)
    {
    	const char *prop;
    	int chosen_node;
    	int len;
    
    	if (!blob)
    		return -FDT_ERR_NOTFOUND;
    	chosen_node = fdt_path_offset(blob, "/chosen");
    	prop = fdt_getprop(blob, chosen_node, name, &len);
    	if (!prop)
    		return -FDT_ERR_NOTFOUND;
    	return fdt_path_offset(blob, prop);
    }
    
    
    int fdtdec_check_fdt(void)
    {
    	/*
    	 * We must have an FDT, but we cannot panic() yet since the console
    	 * is not ready. So for now, just assert(). Boards which need an early
    	 * FDT (prior to console ready) will need to make their own
    	 * arrangements and do their own checks.
    	 */
    	assert(!fdtdec_prepare_fdt());
    	return 0;
    }
    
    
    /*
     * This function is a little odd in that it accesses global data. At some
     * point if the architecture board.c files merge this will make more sense.
     * Even now, it is common code.
     */
    
    int fdtdec_prepare_fdt(void)
    
    	if (!gd->fdt_blob || ((uintptr_t)gd->fdt_blob & 3) ||
    	    fdt_check_header(gd->fdt_blob)) {
    
    #ifdef CONFIG_SPL_BUILD
    		puts("Missing DTB\n");
    #else
    		puts("No valid device tree binary found - please append one to U-Boot binary, use u-boot-dtb.bin or define CONFIG_OF_EMBED. For sandbox, use -d <file.dtb>\n");
    #endif
    
    	return 0;
    }
    
    
    int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name)
    {
    	const u32 *phandle;
    	int lookup;
    
    
    	debug("%s: %s\n", __func__, prop_name);
    
    	phandle = fdt_getprop(blob, node, prop_name, NULL);
    	if (!phandle)
    		return -FDT_ERR_NOTFOUND;
    
    	lookup = fdt_node_offset_by_phandle(blob, fdt32_to_cpu(*phandle));
    	return lookup;
    }
    
    /**
     * Look up a property in a node and check that it has a minimum length.
     *
     * @param blob		FDT blob
     * @param node		node to examine
     * @param prop_name	name of property to find
     * @param min_len	minimum property length in bytes
     * @param err		0 if ok, or -FDT_ERR_NOTFOUND if the property is not
    			found, or -FDT_ERR_BADLAYOUT if not enough data
     * @return pointer to cell, which is only valid if err == 0
     */
    static const void *get_prop_check_min_len(const void *blob, int node,
    		const char *prop_name, int min_len, int *err)
    {
    	const void *cell;
    	int len;
    
    	debug("%s: %s\n", __func__, prop_name);
    	cell = fdt_getprop(blob, node, prop_name, &len);
    	if (!cell)
    		*err = -FDT_ERR_NOTFOUND;
    	else if (len < min_len)
    		*err = -FDT_ERR_BADLAYOUT;
    	else
    		*err = 0;
    	return cell;
    }
    
    int fdtdec_get_int_array(const void *blob, int node, const char *prop_name,
    		u32 *array, int count)
    {
    	const u32 *cell;
    	int i, err = 0;
    
    	debug("%s: %s\n", __func__, prop_name);
    	cell = get_prop_check_min_len(blob, node, prop_name,
    				      sizeof(u32) * count, &err);
    	if (!err) {
    		for (i = 0; i < count; i++)
    			array[i] = fdt32_to_cpu(cell[i]);
    	}
    	return err;
    }
    
    
    int fdtdec_get_int_array_count(const void *blob, int node,
    			       const char *prop_name, u32 *array, int count)
    {
    	const u32 *cell;
    	int len, elems;
    	int i;
    
    	debug("%s: %s\n", __func__, prop_name);
    	cell = fdt_getprop(blob, node, prop_name, &len);
    	if (!cell)
    		return -FDT_ERR_NOTFOUND;
    	elems = len / sizeof(u32);
    	if (count > elems)
    		count = elems;
    	for (i = 0; i < count; i++)
    		array[i] = fdt32_to_cpu(cell[i]);
    
    	return count;
    }
    
    
    const u32 *fdtdec_locate_array(const void *blob, int node,
    			       const char *prop_name, int count)
    {
    	const u32 *cell;
    	int err;
    
    	cell = get_prop_check_min_len(blob, node, prop_name,
    				      sizeof(u32) * count, &err);
    	return err ? NULL : cell;
    }
    
    
    int fdtdec_get_bool(const void *blob, int node, const char *prop_name)
    {
    	const s32 *cell;
    	int len;
    
    	debug("%s: %s\n", __func__, prop_name);
    	cell = fdt_getprop(blob, node, prop_name, &len);
    	return cell != NULL;
    }
    
    int fdtdec_parse_phandle_with_args(const void *blob, int src_node,
    				   const char *list_name,
    				   const char *cells_name,
    				   int cell_count, int index,
    				   struct fdtdec_phandle_args *out_args)
    {
    	const __be32 *list, *list_end;
    	int rc = 0, size, cur_index = 0;
    	uint32_t count = 0;
    	int node = -1;
    	int phandle;
    
    	/* Retrieve the phandle list property */
    	list = fdt_getprop(blob, src_node, list_name, &size);
    	if (!list)
    		return -ENOENT;
    	list_end = list + size / sizeof(*list);
    
    	/* Loop over the phandles until all the requested entry is found */
    	while (list < list_end) {
    		rc = -EINVAL;
    		count = 0;
    
    		/*
    		 * If phandle is 0, then it is an empty entry with no
    		 * arguments.  Skip forward to the next entry.
    		 */
    		phandle = be32_to_cpup(list++);
    		if (phandle) {
    			/*
    			 * Find the provider node and parse the #*-cells
    			 * property to determine the argument length.
    			 *
    			 * This is not needed if the cell count is hard-coded
    			 * (i.e. cells_name not set, but cell_count is set),
    			 * except when we're going to return the found node
    			 * below.
    			 */
    			if (cells_name || cur_index == index) {
    				node = fdt_node_offset_by_phandle(blob,
    								  phandle);
    				if (!node) {
    					debug("%s: could not find phandle\n",
    					      fdt_get_name(blob, src_node,
    							   NULL));
    					goto err;
    				}
    			}
    
    			if (cells_name) {
    				count = fdtdec_get_int(blob, node, cells_name,
    						       -1);
    				if (count == -1) {
    					debug("%s: could not get %s for %s\n",
    					      fdt_get_name(blob, src_node,
    							   NULL),
    					      cells_name,
    					      fdt_get_name(blob, node,
    							   NULL));
    					goto err;
    				}
    			} else {
    				count = cell_count;
    			}
    
    			/*
    			 * Make sure that the arguments actually fit in the
    			 * remaining property data length
    			 */
    			if (list + count > list_end) {
    				debug("%s: arguments longer than property\n",
    				      fdt_get_name(blob, src_node, NULL));
    				goto err;
    			}
    		}
    
    		/*
    		 * All of the error cases above bail out of the loop, so at
    		 * this point, the parsing is successful. If the requested
    		 * index matches, then fill the out_args structure and return,
    		 * or return -ENOENT for an empty entry.
    		 */
    		rc = -ENOENT;
    		if (cur_index == index) {
    			if (!phandle)
    				goto err;
    
    			if (out_args) {
    				int i;
    
    				if (count > MAX_PHANDLE_ARGS) {
    					debug("%s: too many arguments %d\n",
    					      fdt_get_name(blob, src_node,
    							   NULL), count);
    					count = MAX_PHANDLE_ARGS;
    				}
    				out_args->node = node;
    				out_args->args_count = count;
    				for (i = 0; i < count; i++) {
    					out_args->args[i] =
    							be32_to_cpup(list++);
    				}
    			}
    
    			/* Found it! return success */
    			return 0;
    		}
    
    		node = -1;
    		list += count;
    		cur_index++;
    	}
    
    	/*
    	 * Result will be one of:
    	 * -ENOENT : index is for empty phandle
    	 * -EINVAL : parsing error on data
    	 * [1..n]  : Number of phandle (count mode; when index = -1)
    	 */
    	rc = index < 0 ? cur_index : -ENOENT;
     err:
    	return rc;
    }
    
    
    int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name,
    		u8 *array, int count)
    {
    	const u8 *cell;
    	int err;
    
    	cell = get_prop_check_min_len(blob, node, prop_name, count, &err);
    	if (!err)
    		memcpy(array, cell, count);
    	return err;
    }
    
    const u8 *fdtdec_locate_byte_array(const void *blob, int node,
    			     const char *prop_name, int count)
    {
    	const u8 *cell;
    	int err;
    
    	cell = get_prop_check_min_len(blob, node, prop_name, count, &err);
    	if (err)
    		return NULL;
    	return cell;
    }
    
    
    int fdtdec_get_config_int(const void *blob, const char *prop_name,
    		int default_val)
    {
    	int config_node;
    
    	debug("%s: %s\n", __func__, prop_name);
    	config_node = fdt_path_offset(blob, "/config");
    	if (config_node < 0)
    		return default_val;
    	return fdtdec_get_int(blob, config_node, prop_name, default_val);
    }
    
    int fdtdec_get_config_bool(const void *blob, const char *prop_name)
    {
    	int config_node;
    	const void *prop;
    
    	debug("%s: %s\n", __func__, prop_name);
    	config_node = fdt_path_offset(blob, "/config");
    	if (config_node < 0)
    		return 0;
    	prop = fdt_get_property(blob, config_node, prop_name, NULL);
    
    	return prop != NULL;
    }
    
    
    char *fdtdec_get_config_string(const void *blob, const char *prop_name)
    {
    	const char *nodep;
    	int nodeoffset;
    	int len;
    
    	debug("%s: %s\n", __func__, prop_name);
    	nodeoffset = fdt_path_offset(blob, "/config");
    	if (nodeoffset < 0)
    		return NULL;
    
    	nodep = fdt_getprop(blob, nodeoffset, prop_name, &len);
    	if (!nodep)
    		return NULL;
    
    	return (char *)nodep;
    }
    
    int fdtdec_decode_region(const void *blob, int node, const char *prop_name,
    			 fdt_addr_t *basep, fdt_size_t *sizep)
    
    	debug("%s: %s: %s\n", __func__, fdt_get_name(blob, node, NULL),
    	      prop_name);
    
    	cell = fdt_getprop(blob, node, prop_name, &len);
    
    	if (!cell || (len < sizeof(fdt_addr_t) * 2)) {
    		debug("cell=%p, len=%d\n", cell, len);
    
    	}
    
    	*basep = fdt_addr_to_cpu(*cell);
    	*sizep = fdt_size_to_cpu(cell[1]);
    	debug("%s: base=%08lx, size=%lx\n", __func__, (ulong)*basep,
    	      (ulong)*sizep);
    
    
    /**
     * Read a flash entry from the fdt
     *
     * @param blob		FDT blob
     * @param node		Offset of node to read
     * @param name		Name of node being read
     * @param entry		Place to put offset and size of this node
     * @return 0 if ok, -ve on error
     */
    int fdtdec_read_fmap_entry(const void *blob, int node, const char *name,
    			   struct fmap_entry *entry)
    {
    
    	u32 reg[2];
    
    	if (fdtdec_get_int_array(blob, node, "reg", reg, 2)) {
    		debug("Node '%s' has bad/missing 'reg' property\n", name);
    		return -FDT_ERR_NOTFOUND;
    	}
    	entry->offset = reg[0];
    	entry->length = reg[1];
    
    	entry->used = fdtdec_get_int(blob, node, "used", entry->length);
    	prop = fdt_getprop(blob, node, "compress", NULL);
    	entry->compress_algo = prop && !strcmp(prop, "lzo") ?
    		FMAP_COMPRESS_LZO : FMAP_COMPRESS_NONE;
    	prop = fdt_getprop(blob, node, "hash", &entry->hash_size);
    	entry->hash_algo = prop ? FMAP_HASH_SHA256 : FMAP_HASH_NONE;
    	entry->hash = (uint8_t *)prop;
    
    u64 fdtdec_get_number(const fdt32_t *ptr, unsigned int cells)
    
    {
    	u64 number = 0;
    
    	while (cells--)
    		number = (number << 32) | fdt32_to_cpu(*ptr++);
    
    	return number;
    }
    
    int fdt_get_resource(const void *fdt, int node, const char *property,
    		     unsigned int index, struct fdt_resource *res)
    {
    	const fdt32_t *ptr, *end;
    	int na, ns, len, parent;
    	unsigned int i = 0;
    
    	parent = fdt_parent_offset(fdt, node);
    	if (parent < 0)
    		return parent;
    
    	na = fdt_address_cells(fdt, parent);
    	ns = fdt_size_cells(fdt, parent);
    
    	ptr = fdt_getprop(fdt, node, property, &len);
    	if (!ptr)
    		return len;
    
    	end = ptr + len / sizeof(*ptr);
    
    	while (ptr + na + ns <= end) {
    		if (i == index) {
    			res->start = res->end = fdtdec_get_number(ptr, na);
    			res->end += fdtdec_get_number(&ptr[na], ns) - 1;
    			return 0;
    		}
    
    		ptr += na + ns;
    		i++;
    	}
    
    	return -FDT_ERR_NOTFOUND;
    }
    
    int fdt_get_named_resource(const void *fdt, int node, const char *property,
    			   const char *prop_names, const char *name,
    			   struct fdt_resource *res)
    {
    	int index;
    
    	index = fdt_find_string(fdt, node, prop_names, name);
    	if (index < 0)
    		return index;
    
    	return fdt_get_resource(fdt, node, property, index, res);
    }
    
    int fdtdec_decode_memory_region(const void *blob, int config_node,
    				const char *mem_type, const char *suffix,
    				fdt_addr_t *basep, fdt_size_t *sizep)
    {
    	char prop_name[50];
    	const char *mem;
    	fdt_size_t size, offset_size;
    	fdt_addr_t base, offset;
    	int node;
    
    	if (config_node == -1) {
    		config_node = fdt_path_offset(blob, "/config");
    		if (config_node < 0) {
    			debug("%s: Cannot find /config node\n", __func__);
    			return -ENOENT;
    		}
    	}
    	if (!suffix)
    		suffix = "";
    
    	snprintf(prop_name, sizeof(prop_name), "%s-memory%s", mem_type,
    		 suffix);