lib: utils: Move fdt fixup helper routines to a different file

FDT helper file contain both fdt fixup and parsing functions.

Split the fixup related functions to a separate file for a better code
organization.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

3 files changed, 204 insertions, 187 deletions

diff --git a/lib/utils/fdt/fdt_fixup.c b/lib/utils/fdt/fdt_fixup.c
new file mode 100644
index 0000000..b91e95f
--- /dev/null
+++ b/lib/utils/fdt/fdt_fixup.c
@@ -0,0 +1,203 @@
+// SPDX-License-Identifier: BSD-2-Clause
+/*
+ * fdt_fixup.c - Flat Device Tree parsing helper routines
+ * Implement helper routines to parse FDT nodes on top of
+ * libfdt for OpenSBI usage
+ *
+ * Copyright (C) 2020 Bin Meng <bmeng.cn@gmail.com>
+ */
+
+#include <libfdt.h>
+#include <sbi/riscv_asm.h>
+#include <sbi/sbi_console.h>
+#include <sbi/sbi_platform.h>
+#include <sbi/sbi_scratch.h>
+
+void fdt_cpu_fixup(void *fdt)
+{
+	struct sbi_scratch *scratch = sbi_scratch_thishart_ptr();
+	const struct sbi_platform *plat = sbi_platform_ptr(scratch);
+	char cpu_node[32] = "";
+	int cpu_offset;
+	int err;
+	u32 i;
+
+	err = fdt_open_into(fdt, fdt, fdt_totalsize(fdt) + 32);
+	if (err < 0)
+		return;
+
+	/* assume hart ids are continuous */
+	for (i = 0; i < sbi_platform_hart_count(plat); i++) {
+		sbi_sprintf(cpu_node, "/cpus/cpu@%d", i);
+		cpu_offset = fdt_path_offset(fdt, cpu_node);
+
+		if (sbi_platform_hart_invalid(plat, i))
+			fdt_setprop_string(fdt, cpu_offset, "status",
+					   "disabled");
+
+		memset(cpu_node, 0, sizeof(cpu_node));
+	}
+}
+
+void fdt_plic_fixup(void *fdt, const char *compat)
+{
+	u32 *cells;
+	int i, cells_count;
+	int plic_off;
+
+	plic_off = fdt_node_offset_by_compatible(fdt, 0, compat);
+	if (plic_off < 0)
+		return;
+
+	cells = (u32 *)fdt_getprop(fdt, plic_off,
+				   "interrupts-extended", &cells_count);
+	if (!cells)
+		return;
+
+	cells_count = cells_count / sizeof(u32);
+	if (!cells_count)
+		return;
+
+	for (i = 0; i < (cells_count / 2); i++) {
+		if (fdt32_to_cpu(cells[2 * i + 1]) == IRQ_M_EXT)
+			cells[2 * i + 1] = cpu_to_fdt32(0xffffffff);
+	}
+}
+
+/**
+ * We use PMP to protect OpenSBI firmware to safe-guard it from buggy S-mode
+ * software, see pmp_init() in lib/sbi/sbi_hart.c. The protected memory region
+ * information needs to be conveyed to S-mode software (e.g.: operating system)
+ * via some well-known method.
+ *
+ * With device tree, this can be done by inserting a child node of the reserved
+ * memory node which is used to specify one or more regions of reserved memory.
+ *
+ * For the reserved memory node bindings, see Linux kernel documentation at
+ * Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt
+ *
+ * Some additional memory spaces may be protected by platform codes via PMP as
+ * well, and corresponding child nodes will be inserted.
+ */
+int fdt_reserved_memory_fixup(void *fdt)
+{
+	struct sbi_scratch *scratch = sbi_scratch_thishart_ptr();
+	const struct sbi_platform *plat = sbi_platform_ptr(scratch);
+	unsigned long prot, addr, size;
+	int na = fdt_address_cells(fdt, 0);
+	int ns = fdt_size_cells(fdt, 0);
+	fdt32_t addr_high, addr_low;
+	fdt32_t size_high, size_low;
+	fdt32_t reg[4];
+	fdt32_t *val;
+	char name[32];
+	int parent, subnode;
+	int i, j;
+	int err;
+
+	if (!sbi_platform_has_pmp(plat))
+		return 0;
+
+	/* expand the device tree to accommodate new node */
+	err  = fdt_open_into(fdt, fdt, fdt_totalsize(fdt) + 256);
+	if (err < 0)
+		return err;
+
+	/* try to locate the reserved memory node */
+	parent = fdt_path_offset(fdt, "/reserved-memory");
+	if (parent < 0) {
+		/* if such node does not exist, create one */
+		parent = fdt_add_subnode(fdt, 0, "reserved-memory");
+		if (parent < 0)
+			return parent;
+
+		/*
+		 * reserved-memory node has 3 required properties:
+		 * - #address-cells: the same value as the root node
+		 * - #size-cells: the same value as the root node
+		 * - ranges: should be empty
+		 */
+
+		err = fdt_setprop_empty(fdt, parent, "ranges");
+		if (err < 0)
+			return err;
+
+		err = fdt_setprop_u32(fdt, parent, "#size-cells", ns);
+		if (err < 0)
+			return err;
+
+		err = fdt_setprop_u32(fdt, parent, "#address-cells", na);
+		if (err < 0)
+			return err;
+	}
+
+	/*
+	 * We assume the given device tree does not contain any memory region
+	 * child node protected by PMP. Normally PMP programming happens at
+	 * M-mode firmware. The memory space used by OpenSBI is protected.
+	 * Some additional memory spaces may be protected by platform codes.
+	 *
+	 * With above assumption, we create child nodes directly.
+	 */
+
+	for (i = 0, j = 0; i < PMP_COUNT; i++) {
+		pmp_get(i, &prot, &addr, &size);
+		if (!(prot & PMP_A))
+			continue;
+		if (!(prot & (PMP_R | PMP_W | PMP_X))) {
+			addr_high = (u64)addr >> 32;
+			addr_low = addr;
+			size_high = (u64)size >> 32;
+			size_low = size;
+
+			if (na > 1 && addr_high)
+				sbi_snprintf(name, sizeof(name),
+					     "mmode_pmp%d@%x,%x", j,
+					     addr_high, addr_low);
+			else
+				sbi_snprintf(name, sizeof(name),
+					     "mmode_pmp%d@%x", j,
+					     addr_low);
+
+			subnode = fdt_add_subnode(fdt, parent, name);
+			if (subnode < 0)
+				return subnode;
+
+			/*
+			 * Tell operating system not to create a virtual
+			 * mapping of the region as part of its standard
+			 * mapping of system memory.
+			 */
+			err = fdt_setprop_empty(fdt, subnode, "no-map");
+			if (err < 0)
+				return err;
+
+			/* encode the <reg> property value */
+			val = reg;
+			if (na > 1)
+				*val++ = cpu_to_fdt32(addr_high);
+			*val++ = cpu_to_fdt32(addr_low);
+			if (ns > 1)
+				*val++ = cpu_to_fdt32(size_high);
+			*val++ = cpu_to_fdt32(size_low);
+
+			err = fdt_setprop(fdt, subnode, "reg", reg,
+					  (na + ns) * sizeof(fdt32_t));
+			if (err < 0)
+				return err;
+
+			j++;
+		}
+	}
+
+	return 0;
+}
+
+void fdt_fixups(void *fdt)
+{
+	fdt_plic_fixup(fdt, "riscv,plic0");
+
+	fdt_reserved_memory_fixup(fdt);
+}
+
+
diff --git a/lib/utils/fdt/fdt_helper.c b/lib/utils/fdt/fdt_helper.c
index 81617c9..07f7221 100644
--- a/lib/utils/fdt/fdt_helper.c
+++ b/lib/utils/fdt/fdt_helper.c
@@ -13,193 +13,6 @@
 #include <sbi/sbi_scratch.h>
 #include <sbi_utils/fdt/fdt_helper.h>
 
-void fdt_cpu_fixup(void *fdt)
-{
-	struct sbi_scratch *scratch = sbi_scratch_thishart_ptr();
-	const struct sbi_platform *plat = sbi_platform_ptr(scratch);
-	char cpu_node[32] = "";
-	int cpu_offset;
-	int err;
-	u32 i;
-
-	err = fdt_open_into(fdt, fdt, fdt_totalsize(fdt) + 32);
-	if (err < 0)
-		return;
-
-	/* assume hart ids are continuous */
-	for (i = 0; i < sbi_platform_hart_count(plat); i++) {
-		sbi_sprintf(cpu_node, "/cpus/cpu@%d", i);
-		cpu_offset = fdt_path_offset(fdt, cpu_node);
-
-		if (sbi_platform_hart_invalid(plat, i))
-			fdt_setprop_string(fdt, cpu_offset, "status",
-					   "disabled");
-
-		memset(cpu_node, 0, sizeof(cpu_node));
-	}
-}
-
-void fdt_plic_fixup(void *fdt, const char *compat)
-{
-	u32 *cells;
-	int i, cells_count;
-	int plic_off;
-
-	plic_off = fdt_node_offset_by_compatible(fdt, 0, compat);
-	if (plic_off < 0)
-		return;
-
-	cells = (u32 *)fdt_getprop(fdt, plic_off,
-				   "interrupts-extended", &cells_count);
-	if (!cells)
-		return;
-
-	cells_count = cells_count / sizeof(u32);
-	if (!cells_count)
-		return;
-
-	for (i = 0; i < (cells_count / 2); i++) {
-		if (fdt32_to_cpu(cells[2 * i + 1]) == IRQ_M_EXT)
-			cells[2 * i + 1] = cpu_to_fdt32(0xffffffff);
-	}
-}
-
-/**
- * We use PMP to protect OpenSBI firmware to safe-guard it from buggy S-mode
- * software, see pmp_init() in lib/sbi/sbi_hart.c. The protected memory region
- * information needs to be conveyed to S-mode software (e.g.: operating system)
- * via some well-known method.
- *
- * With device tree, this can be done by inserting a child node of the reserved
- * memory node which is used to specify one or more regions of reserved memory.
- *
- * For the reserved memory node bindings, see Linux kernel documentation at
- * Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt
- *
- * Some additional memory spaces may be protected by platform codes via PMP as
- * well, and corresponding child nodes will be inserted.
- */
-int fdt_reserved_memory_fixup(void *fdt)
-{
-	struct sbi_scratch *scratch = sbi_scratch_thishart_ptr();
-	const struct sbi_platform *plat = sbi_platform_ptr(scratch);
-	unsigned long prot, addr, size;
-	int na = fdt_address_cells(fdt, 0);
-	int ns = fdt_size_cells(fdt, 0);
-	fdt32_t addr_high, addr_low;
-	fdt32_t size_high, size_low;
-	fdt32_t reg[4];
-	fdt32_t *val;
-	char name[32];
-	int parent, subnode;
-	int i, j;
-	int err;
-
-	if (!sbi_platform_has_pmp(plat))
-		return 0;
-
-	/* expand the device tree to accommodate new node */
-	err  = fdt_open_into(fdt, fdt, fdt_totalsize(fdt) + 256);
-	if (err < 0)
-		return err;
-
-	/* try to locate the reserved memory node */
-	parent = fdt_path_offset(fdt, "/reserved-memory");
-	if (parent < 0) {
-		/* if such node does not exist, create one */
-		parent = fdt_add_subnode(fdt, 0, "reserved-memory");
-		if (parent < 0)
-			return parent;
-
-		/*
-		 * reserved-memory node has 3 required properties:
-		 * - #address-cells: the same value as the root node
-		 * - #size-cells: the same value as the root node
-		 * - ranges: should be empty
-		 */
-
-		err = fdt_setprop_empty(fdt, parent, "ranges");
-		if (err < 0)
-			return err;
-
-		err = fdt_setprop_u32(fdt, parent, "#size-cells", ns);
-		if (err < 0)
-			return err;
-
-		err = fdt_setprop_u32(fdt, parent, "#address-cells", na);
-		if (err < 0)
-			return err;
-	}
-
-	/*
-	 * We assume the given device tree does not contain any memory region
-	 * child node protected by PMP. Normally PMP programming happens at
-	 * M-mode firmware. The memory space used by OpenSBI is protected.
-	 * Some additional memory spaces may be protected by platform codes.
-	 *
-	 * With above assumption, we create child nodes directly.
-	 */
-
-	for (i = 0, j = 0; i < PMP_COUNT; i++) {
-		pmp_get(i, &prot, &addr, &size);
-		if (!(prot & PMP_A))
-			continue;
-		if (!(prot & (PMP_R | PMP_W | PMP_X))) {
-			addr_high = (u64)addr >> 32;
-			addr_low = addr;
-			size_high = (u64)size >> 32;
-			size_low = size;
-
-			if (na > 1 && addr_high)
-				sbi_snprintf(name, sizeof(name),
-					     "mmode_pmp%d@%x,%x", j,
-					     addr_high, addr_low);
-			else
-				sbi_snprintf(name, sizeof(name),
-					     "mmode_pmp%d@%x", j,
-					     addr_low);
-
-			subnode = fdt_add_subnode(fdt, parent, name);
-			if (subnode < 0)
-				return subnode;
-
-			/*
-			 * Tell operating system not to create a virtual
-			 * mapping of the region as part of its standard
-			 * mapping of system memory.
-			 */
-			err = fdt_setprop_empty(fdt, subnode, "no-map");
-			if (err < 0)
-				return err;
-
-			/* encode the <reg> property value */
-			val = reg;
-			if (na > 1)
-				*val++ = cpu_to_fdt32(addr_high);
-			*val++ = cpu_to_fdt32(addr_low);
-			if (ns > 1)
-				*val++ = cpu_to_fdt32(size_high);
-			*val++ = cpu_to_fdt32(size_low);
-
-			err = fdt_setprop(fdt, subnode, "reg", reg,
-					  (na + ns) * sizeof(fdt32_t));
-			if (err < 0)
-				return err;
-
-			j++;
-		}
-	}
-
-	return 0;
-}
-
-void fdt_fixups(void *fdt)
-{
-	fdt_plic_fixup(fdt, "riscv,plic0");
-
-	fdt_reserved_memory_fixup(fdt);
-}
-
 static int fdt_get_node_addr_size(void *fdt, int node, unsigned long *addr,
 				  unsigned long *size)
 {
diff --git a/lib/utils/fdt/objects.mk b/lib/utils/fdt/objects.mk
index 062e6bd..b860a83 100644
--- a/lib/utils/fdt/objects.mk
+++ b/lib/utils/fdt/objects.mk
@@ -5,3 +5,4 @@
 #
 
 libsbiutils-objs-y += fdt/fdt_helper.o
+libsbiutils-objs-y += fdt/fdt_fixup.o