libfdt: add fdt_append_addrrange()

This function will append an address range property using parent node's
"#address-cells" and "#size-cells" properties.

It will be used in implementing kdump with kexec_file_load system call
at linux kernel for arm64 once it is merged into kernel tree.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Message-Id: <20190327061552.17170-2-takahiro.akashi@linaro.org>
[dwg: Correct a SEGV error in the testcase]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

libfdt/fdt_addresses.c

@@ -95,3 +95,50 @@ int fdt_size_cells(const void *fdt, int nodeoffset)
 		return 1;
 	return val;
 }
+
+/* This function assumes that [address|size]_cells is 1 or 2 */
+int fdt_appendprop_addrrange(void *fdt, int parent, int nodeoffset,
+			     const char *name, uint64_t addr, uint64_t size)
+{
+	int addr_cells, size_cells, ret;
+	uint8_t data[sizeof(fdt64_t) * 2], *prop;
+
+	ret = fdt_address_cells(fdt, parent);
+	if (ret < 0)
+		return ret;
+	addr_cells = ret;
+
+	ret = fdt_size_cells(fdt, parent);
+	if (ret < 0)
+		return ret;
+	size_cells = ret;
+
+	/* check validity of address */
+	prop = data;
+	if (addr_cells == 1) {
+		if ((addr > UINT32_MAX) || ((UINT32_MAX + 1 - addr) < size))
+			return -FDT_ERR_BADVALUE;
+
+		fdt32_st(prop, (uint32_t)addr);
+	} else if (addr_cells == 2) {
+		fdt64_st(prop, addr);
+	} else {
+		return -FDT_ERR_BADNCELLS;
+	}
+
+	/* check validity of size */
+	prop += addr_cells * sizeof(fdt32_t);
+	if (size_cells == 1) {
+		if (size > UINT32_MAX)
+			return -FDT_ERR_BADVALUE;
+
+		fdt32_st(prop, (uint32_t)size);
+	} else if (size_cells == 2) {
+		fdt64_st(prop, size);
+	} else {
+		return -FDT_ERR_BADNCELLS;
+	}
+
+	return fdt_appendprop(fdt, nodeoffset, name, data,
+			      (addr_cells + size_cells) * sizeof(fdt32_t));
+}

libfdt/libfdt.h

@@ -171,6 +171,16 @@ static inline uint32_t fdt32_ld(const fdt32_t *p)
 		| bp[3];
 }
 
+static inline void fdt32_st(void *property, uint32_t value)
+{
+	uint8_t *bp = property;
+
+	bp[0] = value >> 24;
+	bp[1] = (value >> 16) & 0xff;
+	bp[2] = (value >> 8) & 0xff;
+	bp[3] = value & 0xff;
+}
+
 static inline uint64_t fdt64_ld(const fdt64_t *p)
 {
 	const uint8_t *bp = (const uint8_t *)p;
@@ -185,6 +195,20 @@ static inline uint64_t fdt64_ld(const fdt64_t *p)
 		| bp[7];
 }
 
+static inline void fdt64_st(void *property, uint64_t value)
+{
+	uint8_t *bp = property;
+
+	bp[0] = value >> 56;
+	bp[1] = (value >> 48) & 0xff;
+	bp[2] = (value >> 40) & 0xff;
+	bp[3] = (value >> 32) & 0xff;
+	bp[4] = (value >> 24) & 0xff;
+	bp[5] = (value >> 16) & 0xff;
+	bp[6] = (value >> 8) & 0xff;
+	bp[7] = value & 0xff;
+}
+
 /**********************************************************************/
 /* Traversal functions                                                */
 /**********************************************************************/
@@ -1831,6 +1855,43 @@ static inline int fdt_appendprop_cell(void *fdt, int nodeoffset,
 #define fdt_appendprop_string(fdt, nodeoffset, name, str) \
 	fdt_appendprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
 
+/**
+ * fdt_appendprop_addrrange - append a address range property
+ * @fdt: pointer to the device tree blob
+ * @parent: offset of the parent node
+ * @nodeoffset: offset of the node to add a property at
+ * @name: name of property
+ * @addr: start address of a given range
+ * @size: size of a given range
+ *
+ * fdt_appendprop_addrrange() appends an address range value (start
+ * address and size) to the value of the named property in the given
+ * node, or creates a new property with that value if it does not
+ * already exist.
+ * If "name" is not specified, a default "reg" is used.
+ * Cell sizes are determined by parent's #address-cells and #size-cells.
+ *
+ * This function may insert data into the blob, and will therefore
+ * change the offsets of some existing nodes.
+ *
+ * returns:
+ *	0, on success
+ *	-FDT_ERR_BADLAYOUT,
+ *	-FDT_ERR_BADMAGIC,
+ *	-FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
+ *		#address-cells property
+ *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
+ *	-FDT_ERR_BADSTATE,
+ *	-FDT_ERR_BADSTRUCTURE,
+ *	-FDT_ERR_BADVERSION,
+ *	-FDT_ERR_BADVALUE, addr or size doesn't fit to respective cells size
+ *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
+ *		contain a new property
+ *	-FDT_ERR_TRUNCATED, standard meanings
+ */
+int fdt_appendprop_addrrange(void *fdt, int parent, int nodeoffset,
+			     const char *name, uint64_t addr, uint64_t size);
+
 /**
  * fdt_delprop - delete a property
  * @fdt: pointer to the device tree blob

tests/.gitignore

@@ -8,6 +8,7 @@ tmp.*
 /addr_size_cells
 /addr_size_cells2
 /appendprop[12]
+/appendprop_addrrange
 /asm_tree_dump
 /boot-cpuid
 /char_literal

tests/Makefile.tests

@@ -10,6 +10,7 @@ LIB_TESTS_L = get_mem_rsv \
 	notfound \
 	addr_size_cells \
 	addr_size_cells2 \
+	appendprop_addrrange \
 	stringlist \
 	setprop_inplace nop_property nop_node \
 	sw_tree1 sw_states \

tests/appendprop_addrrange.c

@@ -0,0 +1,108 @@
+/*
+ * libfdt - Flat Device Tree manipulation
+ *	Testcase for fdt_appendprop_addrrange()
+ * Copyright (C) 2018 AKASHI Takahiro, Linaro Limited
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public License
+ * as published by the Free Software Foundation; either version 2.1 of
+ * the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdint.h>
+
+#include <libfdt.h>
+
+#include "tests.h"
+#include "testdata.h"
+
+int main(int argc, char *argv[])
+{
+	void *fdt, *buf;
+	int offset, xac, xsc, num, i, err;
+	uint64_t addr, size;
+
+	if (argc != 5)
+		CONFIG("Usage: %s <dtb file> <address-cells> <size-cells> <num>\n",
+		       argv[0]);
+
+	test_init(argc, argv);
+	fdt = load_blob(argv[1]);
+	xac = strtol(argv[2], NULL, 10);
+	xsc = strtol(argv[3], NULL, 10);
+	num = strtol(argv[4], NULL, 10);
+
+	buf = xmalloc(0x1000);
+	if (!buf)
+		FAIL("Couldn't allocate temporary buffer");
+	err = fdt_open_into(fdt, buf, 0x1000);
+	if (err)
+		FAIL("fdt_open_into(): %s", fdt_strerror(err));
+
+	fdt = buf;
+
+	/* Set up */
+	err = fdt_setprop_cell(fdt, 0, "#address-cells", xac);
+	if (err)
+		FAIL("fdt_setprop_cell(\"#address-cells\"): %s",
+		     fdt_strerror(err));
+	err = fdt_setprop_cell(fdt, 0, "#size-cells", xsc);
+	if (err)
+		FAIL("fdt_setprop_cell(\"#size-cells\"): %s",
+		     fdt_strerror(err));
+
+	offset = fdt_path_offset(fdt, "/node@1");
+	if (offset < 0)
+		FAIL("Couldn't find path %s", "/node@1");
+
+	addr = TEST_MEMREGION_ADDR;
+	if (xac > 1)
+		addr += TEST_MEMREGION_ADDR_HI;
+	size = TEST_MEMREGION_SIZE;
+	if (xsc > 1)
+		size += TEST_MEMREGION_SIZE_HI;
+
+	/*
+	 * Do test
+	 */
+	/* 1. repeat append's */
+	for (i = 0; i < num; i++) {
+		err = fdt_appendprop_addrrange(fdt, 0, offset,
+					       "prop-memregion", addr, size);
+		if (err)
+			FAIL("Failed to append[%d] \"prop-memregion\": %s",
+			     i, fdt_strerror(err));
+
+		check_getprop_addrrange(fdt, 0, offset, "prop-memregion",
+					i + 1);
+
+		addr += size;
+		size += TEST_MEMREGION_SIZE_INC;
+	}
+
+	/* 2. default property name */
+	addr = TEST_MEMREGION_ADDR;
+	if (xac > 1)
+		addr += TEST_MEMREGION_ADDR_HI;
+	size = TEST_MEMREGION_SIZE;
+	if (xsc > 1)
+		size += TEST_MEMREGION_SIZE_HI;
+
+	err = fdt_appendprop_addrrange(fdt, 0, offset, "reg", addr, size);
+	if (err)
+		FAIL("Failed to set \"reg\": %s", fdt_strerror(err));
+	check_getprop_addrrange(fdt, 0, offset, "reg", 1);
+
+	PASS();
+}

tests/run_tests.sh

@@ -424,6 +424,11 @@ libfdt_tests () {
     run_dtc_test -I dts -O dtb -o property_iterate.dtb property_iterate.dts
     run_test property_iterate property_iterate.dtb
 
+    run_dtc_test -I dts -O dtb -o unit-addr-without-reg.dtb unit-addr-without-reg.dts
+    run_test appendprop_addrrange unit-addr-without-reg.dtb 1 1 1
+    run_test appendprop_addrrange unit-addr-without-reg.dtb 2 2 2
+    run_test appendprop_addrrange unit-addr-without-reg.dtb 2 1 3
+
     # Tests for behaviour on various sorts of corrupted trees
     run_test truncated_property
     run_test truncated_string

tests/testdata.h

@@ -40,6 +40,12 @@
 #define TEST_CHAR4	'\''
 #define TEST_CHAR5	'\xff'
 
+#define TEST_MEMREGION_ADDR	0x12345678
+#define TEST_MEMREGION_ADDR_HI	0x8765432100000000
+#define TEST_MEMREGION_SIZE	0x9abcdef0
+#define TEST_MEMREGION_SIZE_HI	0x0fedcba900000000
+#define TEST_MEMREGION_SIZE_INC	0x1000
+
 #ifndef __ASSEMBLY__
 extern struct fdt_header test_tree1;
 extern struct fdt_header truncated_property;

tests/tests.h

@@ -128,6 +128,9 @@ const void *check_get_prop_offset(void *fdt, int poffset, const char *in_name,
 		check_get_prop_offset(fdt, poffset, name, sizeof(x), &x); \
 	})
 
+const void *check_getprop_addrrange(void *fdt, int parent, int nodeoffset,
+				    const char *name, int num);
+
 int nodename_eq(const char *s1, const char *s2);
 void vg_prepare_blob(void *fdt, size_t bufsize);
 void *load_blob(const char *filename);

tests/testutils.c

@@ -45,6 +45,7 @@ static inline void VALGRIND_MAKE_MEM_DEFINED(void *p, size_t len)
 #include <libfdt.h>
 
 #include "tests.h"
+#include "testdata.h"
 
 /* For FDT_SW_MAGIC */
 #include "libfdt_internal.h"
@@ -184,6 +185,63 @@ const void *check_get_prop_offset(void *fdt, int poffset, const char *exp_name,
 	return propval;
 }
 
+const void *check_getprop_addrrange(void *fdt, int parent, int nodeoffset,
+				    const char *name, int num)
+{
+	const void *propval;
+	int xac, xsc, buf_size, cells, i;
+	char *buf, *p;
+	uint64_t addr, size;
+	fdt32_t val;
+
+	xac = fdt_address_cells(fdt, parent);
+	xsc = fdt_size_cells(fdt, parent);
+
+	if (xac <= 0)
+		FAIL("Couldn't identify #address-cells: %s",
+		     fdt_strerror(xac));
+	if (xsc <= 0)
+		FAIL("Couldn't identify #size-cells: %s",
+		     fdt_strerror(xsc));
+
+	buf_size = (xac + xsc) * sizeof(fdt32_t) * num;
+	buf = malloc(buf_size);
+	if (!buf)
+		FAIL("Couldn't allocate temporary buffer");
+
+	/* expected value */
+	addr = TEST_MEMREGION_ADDR;
+	if (xac > 1)
+		addr += TEST_MEMREGION_ADDR_HI;
+	size = TEST_MEMREGION_SIZE;
+	if (xsc > 1)
+		size += TEST_MEMREGION_SIZE_HI;
+	for (p = buf, i = 0; i < num; i++) {
+		cells = xac;
+		while (cells) {
+			val = cpu_to_fdt32(addr >> (32 * (--cells)));
+			memcpy(p, &val, sizeof(val));
+			p += sizeof(val);
+		}
+		cells = xsc;
+		while (cells) {
+			val = cpu_to_fdt32(size >> (32 * (--cells)));
+			memcpy(p, &val, sizeof(val));
+			p += sizeof(val);
+		}
+
+		addr += size;
+		size += TEST_MEMREGION_SIZE_INC;
+	}
+
+	/* check */
+	propval = check_getprop(fdt, nodeoffset, name, buf_size,
+				(const void *)buf);
+
+	free(buf);
+
+	return propval;
+}
 
 int nodename_eq(const char *s1, const char *s2)
 {