openwrt/target/linux/airoha/patches-6.6/902-mtd-parser-add-support-for-Airoha-parser.patch

From ca46c5834ba3a74595a93d7a491fa9c943be7c30 Mon Sep 17 00:00:00 2001
From: Christian Marangi <ansuelsmth@gmail.com>
Date: Sun, 28 Jul 2024 12:15:53 +0200
Subject: [PATCH 3/3] mtd: parser: add support for Airoha parser

Add support for Airoha parser based on a post parse ofpart function.

Airoha partition table follow normal fixed-partition implementation
with a special implementation for the ART partition. This is always the
past partition and is placed from the end of the flash - the partition
size.

To enable this special implementation for ART partition, the relevant
node require the "airoha,dynamic-art" compatible. With that declared,
offset value is ignored and real offset is updated with the calculated
value.

Due to usage of specific bad block management driver, the MTD size might
vary hence the ART partition offset needs to be dynamically parsed and
can't be declared statically.

Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
---
 drivers/mtd/parsers/Kconfig         | 10 ++++++
 drivers/mtd/parsers/Makefile        |  1 +
 drivers/mtd/parsers/ofpart_airoha.c | 56 +++++++++++++++++++++++++++++
 drivers/mtd/parsers/ofpart_airoha.h | 18 ++++++++++
 drivers/mtd/parsers/ofpart_core.c   |  6 ++++
 5 files changed, 91 insertions(+)
 create mode 100644 drivers/mtd/parsers/ofpart_airoha.c
 create mode 100644 drivers/mtd/parsers/ofpart_airoha.h

--- a/drivers/mtd/parsers/Kconfig
+++ b/drivers/mtd/parsers/Kconfig
@@ -93,6 +93,16 @@ config MTD_OF_PARTS
 	  flash memory node, as described in
 	  Documentation/devicetree/bindings/mtd/mtd.yaml.
 
+config MTD_OF_PARTS_AIROHA
+	bool "Airoha EN7815 partitioning support"
+	depends on MTD_OF_PARTS && (ARCH_AIROHA || COMPILE_TEST)
+	default ARCH_AIROHA
+	help
+	  This provides partitions parser for Airoha EN7815 family devices
+	  that can have dynamic "ART" partition at the end of the flash.
+	  It takes care of finding the correct offset and update property
+	  with it.
+
 config MTD_OF_PARTS_BCM4908
 	bool "BCM4908 partitioning support"
 	depends on MTD_OF_PARTS && (ARCH_BCMBCA || COMPILE_TEST)
--- a/drivers/mtd/parsers/Makefile
+++ b/drivers/mtd/parsers/Makefile
@@ -7,6 +7,7 @@ obj-$(CONFIG_MTD_CMDLINE_PARTS)		+= cmdl
 obj-$(CONFIG_MTD_MYLOADER_PARTS)		+= myloader.o
 obj-$(CONFIG_MTD_OF_PARTS)		+= ofpart.o
 ofpart-y				+= ofpart_core.o
+ofpart-$(CONFIG_MTD_OF_PARTS_AIROHA)	+= ofpart_airoha.o
 ofpart-$(CONFIG_MTD_OF_PARTS_BCM4908)	+= ofpart_bcm4908.o
 ofpart-$(CONFIG_MTD_OF_PARTS_LINKSYS_NS)+= ofpart_linksys_ns.o
 obj-$(CONFIG_MTD_PARSER_IMAGETAG)	+= parser_imagetag.o
--- /dev/null
+++ b/drivers/mtd/parsers/ofpart_airoha.c
@@ -0,0 +1,56 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2024 Christian Marangi <ansuelsmth@gmail.com>
+ */
+
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/partitions.h>
+
+#include "ofpart_airoha.h"
+
+int airoha_partitions_post_parse(struct mtd_info *mtd,
+				 struct mtd_partition *parts,
+				 int nr_parts)
+{
+	struct mtd_partition *part;
+	int len, a_cells, s_cells;
+	struct device_node *pp;
+	struct property *prop;
+	const __be32 *reg;
+	__be32 *new_reg;
+
+	part = &parts[nr_parts - 1];
+	pp = part->of_node;
+
+	/* Skip if ART partition have a valid offset instead of a dynamic one */
+	if (!of_device_is_compatible(pp, "airoha,dynamic-art"))
+		return 0;
+
+	/* ART partition is set at the end of flash - size */
+	part->offset = mtd->size - part->size;
+
+	/* Update the offset with the new calculate value in DT */
+	prop = kzalloc(sizeof(*prop), GFP_KERNEL);
+	if (!prop)
+		return -ENOMEM;
+
+	/* Reg already validated by fixed-partition parser */
+	reg = of_get_property(pp, "reg", &len);
+
+	/* Fixed partition */
+	a_cells = of_n_addr_cells(pp);
+	s_cells = of_n_size_cells(pp);
+
+	prop->name = "reg";
+	prop->length = (a_cells + s_cells) * sizeof(__be32);
+	prop->value = kmemdup(reg, (a_cells + s_cells) * sizeof(__be32),
+			      GFP_KERNEL);
+	new_reg = prop->value;
+	memset(new_reg, 0, a_cells * sizeof(__be32));
+	new_reg[a_cells - 1] = cpu_to_be32(part->offset);
+	if (a_cells > 1)
+		new_reg[0] = cpu_to_be32(part->offset >> 32);
+	of_update_property(pp, prop);
+
+	return 0;
+}
--- /dev/null
+++ b/drivers/mtd/parsers/ofpart_airoha.h
@@ -0,0 +1,18 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __OFPART_AIROHA_H
+#define __OFPART_AIROHA_H
+
+#ifdef CONFIG_MTD_OF_PARTS_AIROHA
+int airoha_partitions_post_parse(struct mtd_info *mtd,
+				 struct mtd_partition *parts,
+				 int nr_parts);
+#else
+static inline int airoha_partitions_post_parse(struct mtd_info *mtd,
+					       struct mtd_partition *parts,
+					       int nr_parts)
+{
+	return -EOPNOTSUPP;
+}
+#endif
+
+#endif
--- a/drivers/mtd/parsers/ofpart_core.c
+++ b/drivers/mtd/parsers/ofpart_core.c
@@ -16,6 +16,7 @@
 #include <linux/slab.h>
 #include <linux/mtd/partitions.h>
 
+#include "ofpart_airoha.h"
 #include "ofpart_bcm4908.h"
 #include "ofpart_linksys_ns.h"
 
@@ -23,6 +24,10 @@ struct fixed_partitions_quirks {
 	int (*post_parse)(struct mtd_info *mtd, struct mtd_partition *parts, int nr_parts);
 };
 
+static struct fixed_partitions_quirks airoha_partitions_quirks = {
+	.post_parse = airoha_partitions_post_parse,
+};
+
 static struct fixed_partitions_quirks bcm4908_partitions_quirks = {
 	.post_parse = bcm4908_partitions_post_parse,
 };
@@ -192,6 +197,7 @@ static const struct of_device_id parse_o
 	/* Generic */
 	{ .compatible = "fixed-partitions" },
 	/* Customized */
+	{ .compatible = "airoha,fixed-partitions", .data = &airoha_partitions_quirks, },
 	{ .compatible = "brcm,bcm4908-partitions", .data = &bcm4908_partitions_quirks, },
 	{ .compatible = "linksys,ns-partitions", .data = &linksys_ns_partitions_quirks, },
 	{},