[PATCH V3 mtd/next 1/3] dt-bindings: mtd: move partition binding to its own file

[PATCH V3 mtd/next 1/3] dt-bindings: mtd: move partition binding to its own file

[Rafał Miłecki]

From: Rafał Miłecki <rafal@milecki.pl>

Single partition binding is quite common and may be:
1. Used by multiple parsers
2. Extended for more specific cases

Move it to separated file to avoid code duplication.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Reviewed-by: Rob Herring <robh@kernel.org>
---
 .../mtd/partitions/fixed-partitions.yaml      | 33 +------------
 .../bindings/mtd/partitions/partition.yaml    | 47 +++++++++++++++++++
 2 files changed, 48 insertions(+), 32 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/mtd/partitions/partition.yaml

diff --git a/Documentation/devicetree/bindings/mtd/partitions/fixed-partitions.yaml b/Documentation/devicetree/bindings/mtd/partitions/fixed-partitions.yaml
index 6d4a3450e064..ea4cace6a955 100644
--- a/Documentation/devicetree/bindings/mtd/partitions/fixed-partitions.yaml
+++ b/Documentation/devicetree/bindings/mtd/partitions/fixed-partitions.yaml
@@ -27,38 +27,7 @@ properties:
 
 patternProperties:
   "@[0-9a-f]+$":
-    description: node describing a single flash partition
-    type: object
-
-    properties:
-      reg:
-        description: partition's offset and size within the flash
-        maxItems: 1
-
-      label:
-        description: The label / name for this partition. If omitted, the label
-          is taken from the node name (excluding the unit address).
-
-      read-only:
-        description: This parameter, if present, is a hint that this partition
-          should only be mounted read-only. This is usually used for flash
-          partitions containing early-boot firmware images or data which should
-          not be clobbered.
-        type: boolean
-
-      lock:
-        description: Do not unlock the partition at initialization time (not
-          supported on all devices)
-        type: boolean
-
-      slc-mode:
-        description: This parameter, if present, allows one to emulate SLC mode
-          on a partition attached to an MLC NAND thus making this partition
-          immune to paired-pages corruptions
-        type: boolean
-
-    required:
-      - reg
+    $ref: "partition.yaml#"
 
 required:
   - "#address-cells"
diff --git a/Documentation/devicetree/bindings/mtd/partitions/partition.yaml b/Documentation/devicetree/bindings/mtd/partitions/partition.yaml
new file mode 100644
index 000000000000..e1ac08064425
--- /dev/null
+++ b/Documentation/devicetree/bindings/mtd/partitions/partition.yaml
@@ -0,0 +1,47 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mtd/partitions/partition.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Partition
+
+description: |
+  This binding describes a single flash partition. Each partition must have its
+  relative offset and size specified. Depending on partition function extra
+  properties can be used.
+
+maintainers:
+  - Rafał Miłecki <rafal@milecki.pl>
+
+properties:
+  reg:
+    description: partition's offset and size within the flash
+    maxItems: 1
+
+  label:
+    description: The label / name for this partition. If omitted, the label
+      is taken from the node name (excluding the unit address).
+
+  read-only:
+    description: This parameter, if present, is a hint that this partition
+      should only be mounted read-only. This is usually used for flash
+      partitions containing early-boot firmware images or data which should
+      not be clobbered.
+    type: boolean
+
+  lock:
+    description: Do not unlock the partition at initialization time (not
+      supported on all devices)
+    type: boolean
+
+  slc-mode:
+    description: This parameter, if present, allows one to emulate SLC mode
+      on a partition attached to an MLC NAND thus making this partition
+      immune to paired-pages corruptions
+    type: boolean
+
+required:
+  - reg
+
+additionalProperties: true
-- 
2.26.2

[PATCH V3 mtd/next 2/3] dt-bindings: mtd: add binding for BCM4908 partitions

[Rafał Miłecki]

From: Rafał Miłecki <rafal@milecki.pl>

BCM4908 uses fixed partitions layout but function of some partitions may
vary. Some devices use multiple firmware partitions and those partitions
should be marked to let system discover their purpose.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
---
V2: Use enum: [ 1, 2 ] for address & size
    Use ^partition@[0-9a-f]+$ pattern ("partition" was added)
    Drop unneeded allOf
    Add unevaluatedProperties
---
 .../partitions/brcm,bcm4908-partitions.yaml   | 70 +++++++++++++++++++
 1 file changed, 70 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/mtd/partitions/brcm,bcm4908-partitions.yaml

diff --git a/Documentation/devicetree/bindings/mtd/partitions/brcm,bcm4908-partitions.yaml b/Documentation/devicetree/bindings/mtd/partitions/brcm,bcm4908-partitions.yaml
new file mode 100644
index 000000000000..7b113e5e3421
--- /dev/null
+++ b/Documentation/devicetree/bindings/mtd/partitions/brcm,bcm4908-partitions.yaml
@@ -0,0 +1,70 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mtd/partitions/brcm,bcm4908-partitions.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Broadcom BCM4908 partitioning
+
+description: |
+  Broadcom BCM4908 CFE bootloader supports two firmware partitions. One is used
+  for regular booting, the other is treated as fallback.
+
+  This binding allows defining all fixed partitions and marking those containing
+  firmware. System can use that information e.g. for booting or flashing
+  purposes.
+
+maintainers:
+  - Rafał Miłecki <rafal@milecki.pl>
+
+properties:
+  compatible:
+    const: brcm,bcm4908-partitions
+
+  "#address-cells":
+    enum: [ 1, 2 ]
+
+  "#size-cells":
+    enum: [ 1, 2 ]
+
+patternProperties:
+  "^partition@[0-9a-f]+$":
+    $ref: "partition.yaml#"
+    properties:
+      compatible:
+        const: brcm,bcm4908-firmware
+    unevaluatedProperties: false
+
+required:
+  - "#address-cells"
+  - "#size-cells"
+
+additionalProperties: false
+
+examples:
+  - |
+    partitions {
+        compatible = "brcm,bcm4908-partitions";
+        #address-cells = <1>;
+        #size-cells = <1>;
+
+        partition@0 {
+            label = "cferom";
+            reg = <0x0 0x100000>;
+        };
+
+        partition@100000 {
+            compatible = "brcm,bcm4908-firmware";
+            reg = <0x100000 0xf00000>;
+        };
+
+        partition@1000000 {
+            compatible = "brcm,bcm4908-firmware";
+            reg = <0x1000000 0xf00000>;
+        };
+
+        partition@1f00000 {
+            label = "calibration";
+            reg = <0x1f00000 0x100000>;
+        };
+    };
-- 
2.26.2

[PATCH V3 mtd/next 3/3] mtd: parsers: ofpart: support BCM4908 fixed partitions

[Rafał Miłecki]

From: Rafał Miłecki <rafal@milecki.pl>

BCM4908 partitioning is based on fixed layout but allows specifying
multiple firmware partitions. It requires detecting which firmware
partition was used for booting current kernel.

To support such cases without duplicating a lot of code (without copying
most of the ofpart.c code) support for post-parsing callback was added.

BCM4908 callback simply reads offset of currently used firmware
partition from the DT. Bootloader specifies it using the "brcm_blparms"
property.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
---
V3: Add #include "bcm4908-partitions.h" to fix:
drivers/mtd/parsers/bcm4908-partitions.c:45:5: warning: no previous prototype for function 'bcm4908_partitions_post_parse' [-Wmissing-prototypes]
Reported-by: kernel test robot <lkp@intel.com>
---
 drivers/mtd/parsers/Makefile             |  1 +
 drivers/mtd/parsers/bcm4908-partitions.c | 64 ++++++++++++++++++++++++
 drivers/mtd/parsers/bcm4908-partitions.h |  7 +++
 drivers/mtd/parsers/ofpart.c             | 28 ++++++++++-
 4 files changed, 98 insertions(+), 2 deletions(-)
 create mode 100644 drivers/mtd/parsers/bcm4908-partitions.c
 create mode 100644 drivers/mtd/parsers/bcm4908-partitions.h

diff --git a/drivers/mtd/parsers/Makefile b/drivers/mtd/parsers/Makefile
index 50eb0b0a2210..01972a5edc5c 100644
--- a/drivers/mtd/parsers/Makefile
+++ b/drivers/mtd/parsers/Makefile
@@ -4,6 +4,7 @@ obj-$(CONFIG_MTD_BCM47XX_PARTS)		+= bcm47xxpart.o
 obj-$(CONFIG_MTD_BCM63XX_PARTS)		+= bcm63xxpart.o
 obj-$(CONFIG_MTD_CMDLINE_PARTS)		+= cmdlinepart.o
 obj-$(CONFIG_MTD_OF_PARTS)		+= ofpart.o
+obj-$(CONFIG_MTD_OF_PARTS)		+= bcm4908-partitions.o
 obj-$(CONFIG_MTD_PARSER_IMAGETAG)	+= parser_imagetag.o
 obj-$(CONFIG_MTD_AFS_PARTS)		+= afs.o
 obj-$(CONFIG_MTD_PARSER_TRX)		+= parser_trx.o
diff --git a/drivers/mtd/parsers/bcm4908-partitions.c b/drivers/mtd/parsers/bcm4908-partitions.c
new file mode 100644
index 000000000000..40eb3b3801c3
--- /dev/null
+++ b/drivers/mtd/parsers/bcm4908-partitions.c
@@ -0,0 +1,64 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2021 Rafał Miłecki <rafal@milecki.pl>
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/of.h>
+#include <linux/mtd/mtd.h>
+#include <linux/slab.h>
+#include <linux/mtd/partitions.h>
+
+#include "bcm4908-partitions.h"
+
+#define BLPARAMS_FW_OFFSET		"NAND_RFS_OFS"
+
+static long long bcm4908_partitions_fw_offset(void)
+{
+	struct device_node *root;
+	struct property *prop;
+	const char *s;
+
+	root = of_find_node_by_path("/");
+	if (!root)
+		return -ENOENT;
+
+	of_property_for_each_string(root, "brcm_blparms", prop, s) {
+		size_t len = strlen(BLPARAMS_FW_OFFSET);
+		unsigned long offset;
+		int err;
+
+		if (strncmp(s, BLPARAMS_FW_OFFSET, len) || s[len] != '=')
+			continue;
+
+		err = kstrtoul(s + len + 1, 0, &offset);
+		if (err) {
+			pr_err("failed to parse %s\n", s + len + 1);
+			return err;
+		}
+
+		return offset << 10;
+	}
+
+	return -ENOENT;
+}
+
+int bcm4908_partitions_post_parse(struct mtd_info *mtd, struct mtd_partition *parts, int nr_parts)
+{
+	long long fw_offset;
+	int i;
+
+	fw_offset = bcm4908_partitions_fw_offset();
+
+	for (i = 0; i < nr_parts; i++) {
+		if (of_device_is_compatible(parts[i].of_node, "brcm,bcm4908-firmware")) {
+			if (fw_offset < 0 || parts[i].offset == fw_offset)
+				parts[i].name = "firmware";
+			else
+				parts[i].name = "backup";
+		}
+	}
+
+	return 0;
+}
diff --git a/drivers/mtd/parsers/bcm4908-partitions.h b/drivers/mtd/parsers/bcm4908-partitions.h
new file mode 100644
index 000000000000..df25f0487d0a
--- /dev/null
+++ b/drivers/mtd/parsers/bcm4908-partitions.h
@@ -0,0 +1,7 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __BCM4908_PARTITIONS_H
+#define __BCM4908_PARTITIONS_H
+
+int bcm4908_partitions_post_parse(struct mtd_info *mtd, struct mtd_partition *parts, int nr_parts);
+
+#endif
diff --git a/drivers/mtd/parsers/ofpart.c b/drivers/mtd/parsers/ofpart.c
index daf507c123e6..6b221df8401c 100644
--- a/drivers/mtd/parsers/ofpart.c
+++ b/drivers/mtd/parsers/ofpart.c
@@ -16,6 +16,18 @@
 #include <linux/slab.h>
 #include <linux/mtd/partitions.h>
 
+#include "bcm4908-partitions.h"
+
+struct fixed_partitions_quirks {
+	int (*post_parse)(struct mtd_info *mtd, struct mtd_partition *parts, int nr_parts);
+};
+
+struct fixed_partitions_quirks bcm4908_partitions_quirks = {
+	.post_parse = bcm4908_partitions_post_parse,
+};
+
+static const struct of_device_id parse_ofpart_match_table[];
+
 static bool node_has_compatible(struct device_node *pp)
 {
 	return of_get_property(pp, "compatible", NULL);
@@ -25,6 +37,8 @@ static int parse_fixed_partitions(struct mtd_info *master,
 				  const struct mtd_partition **pparts,
 				  struct mtd_part_parser_data *data)
 {
+	const struct fixed_partitions_quirks *quirks;
+	const struct of_device_id *of_id;
 	struct mtd_partition *parts;
 	struct device_node *mtd_node;
 	struct device_node *ofpart_node;
@@ -33,7 +47,6 @@ static int parse_fixed_partitions(struct mtd_info *master,
 	int nr_parts, i, ret = 0;
 	bool dedicated = true;
 
-
 	/* Pull of_node from the master device node */
 	mtd_node = mtd_get_of_node(master);
 	if (!mtd_node)
@@ -50,11 +63,16 @@ static int parse_fixed_partitions(struct mtd_info *master,
 			 master->name, mtd_node);
 		ofpart_node = mtd_node;
 		dedicated = false;
-	} else if (!of_device_is_compatible(ofpart_node, "fixed-partitions")) {
+	}
+
+	of_id = of_match_node(parse_ofpart_match_table, ofpart_node);
+	if (dedicated && !of_id) {
 		/* The 'partitions' subnode might be used by another parser */
 		return 0;
 	}
 
+	quirks = of_id ? of_id->data : NULL;
+
 	/* First count the subnodes */
 	nr_parts = 0;
 	for_each_child_of_node(ofpart_node,  pp) {
@@ -126,6 +144,9 @@ static int parse_fixed_partitions(struct mtd_info *master,
 	if (!nr_parts)
 		goto ofpart_none;
 
+	if (quirks && quirks->post_parse)
+		quirks->post_parse(master, parts, nr_parts);
+
 	*pparts = parts;
 	return nr_parts;
 
@@ -140,7 +161,10 @@ static int parse_fixed_partitions(struct mtd_info *master,
 }
 
 static const struct of_device_id parse_ofpart_match_table[] = {
+	/* Generic */
 	{ .compatible = "fixed-partitions" },
+	/* Customized */
+	{ .compatible = "brcm,bcm4908-partitions", .data = &bcm4908_partitions_quirks, },
 	{},
 };
 MODULE_DEVICE_TABLE(of, parse_ofpart_match_table);
-- 
2.26.2