1 files changed, 225 insertions, 0 deletions
diff --git a/drivers/soc/qcom/cmd-db.c b/drivers/soc/qcom/cmd-db.c
new file mode 100644
index 00000000000..08736ea936a
--- /dev/null
+++ b/drivers/soc/qcom/cmd-db.c
@@ -0,0 +1,225 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2016-2018, 2020, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2024, Qualcomm Innovation Center, Inc. All rights reserved.
+ */
+
+#define pr_fmt(fmt) "cmd-db: " fmt
+
+#include <dm.h>
+#include <dm/ofnode.h>
+#include <dm/device_compat.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/ioport.h>
+#include <linux/byteorder/generic.h>
+
+#include <soc/qcom/cmd-db.h>
+
+#define NUM_PRIORITY		2
+#define MAX_SLV_ID		8
+#define SLAVE_ID_MASK		0x7
+#define SLAVE_ID_SHIFT		16
+#define SLAVE_ID(addr)		FIELD_GET(GENMASK(19, 16), addr)
+#define VRM_ADDR(addr)		FIELD_GET(GENMASK(19, 4), addr)
+
+/**
+ * struct entry_header: header for each entry in cmddb
+ *
+ * @id: resource's identifier
+ * @priority: unused
+ * @addr: the address of the resource
+ * @len: length of the data
+ * @offset: offset from :@data_offset, start of the data
+ */
+struct entry_header {
+	u8 id[8];
+	__le32 priority[NUM_PRIORITY];
+	__le32 addr;
+	__le16 len;
+	__le16 offset;
+};
+
+/**
+ * struct rsc_hdr: resource header information
+ *
+ * @slv_id: id for the resource
+ * @header_offset: entry's header at offset from the end of the cmd_db_header
+ * @data_offset: entry's data at offset from the end of the cmd_db_header
+ * @cnt: number of entries for HW type
+ * @version: MSB is major, LSB is minor
+ * @reserved: reserved for future use.
+ */
+struct rsc_hdr {
+	__le16 slv_id;
+	__le16 header_offset;
+	__le16 data_offset;
+	__le16 cnt;
+	__le16 version;
+	__le16 reserved[3];
+};
+
+/**
+ * struct cmd_db_header: The DB header information
+ *
+ * @version: The cmd db version
+ * @magic: constant expected in the database
+ * @header: array of resources
+ * @checksum: checksum for the header. Unused.
+ * @reserved: reserved memory
+ * @data: driver specific data
+ */
+struct cmd_db_header {
+	__le32 version;
+	u8 magic[4];
+	struct rsc_hdr header[MAX_SLV_ID];
+	__le32 checksum;
+	__le32 reserved;
+	u8 data[];
+};
+
+/**
+ * DOC: Description of the Command DB database.
+ *
+ * At the start of the command DB memory is the cmd_db_header structure.
+ * The cmd_db_header holds the version, checksum, magic key as well as an
+ * array for header for each slave (depicted by the rsc_header). Each h/w
+ * based accelerator is a 'slave' (shared resource) and has slave id indicating
+ * the type of accelerator. The rsc_header is the header for such individual
+ * slaves of a given type. The entries for each of these slaves begin at the
+ * rsc_hdr.header_offset. In addition each slave could have auxiliary data
+ * that may be needed by the driver. The data for the slave starts at the
+ * entry_header.offset to the location pointed to by the rsc_hdr.data_offset.
+ *
+ * Drivers have a stringified key to a slave/resource. They can query the slave
+ * information and get the slave id and the auxiliary data and the length of the
+ * data. Using this information, they can format the request to be sent to the
+ * h/w accelerator and request a resource state.
+ */
+
+static const u8 CMD_DB_MAGIC[] = { 0xdb, 0x30, 0x03, 0x0c };
+
+static bool cmd_db_magic_matches(const struct cmd_db_header *header)
+{
+	const u8 *magic = header->magic;
+
+	return memcmp(magic, CMD_DB_MAGIC, ARRAY_SIZE(CMD_DB_MAGIC)) == 0;
+}
+
+static struct cmd_db_header *cmd_db_header __section(".data") = NULL;
+
+static inline const void *rsc_to_entry_header(const struct rsc_hdr *hdr)
+{
+	u16 offset = le16_to_cpu(hdr->header_offset);
+
+	return cmd_db_header->data + offset;
+}
+
+static inline void *
+rsc_offset(const struct rsc_hdr *hdr, const struct entry_header *ent)
+{
+	u16 offset = le16_to_cpu(hdr->data_offset);
+	u16 loffset = le16_to_cpu(ent->offset);
+
+	return cmd_db_header->data + offset + loffset;
+}
+
+static int cmd_db_get_header(const char *id, const struct entry_header **eh,
+			     const struct rsc_hdr **rh)
+{
+	const struct rsc_hdr *rsc_hdr;
+	const struct entry_header *ent;
+	int i, j;
+	u8 query[sizeof(ent->id)] __nonstring;
+
+	strncpy(query, id, sizeof(query));
+
+	for (i = 0; i < MAX_SLV_ID; i++) {
+		rsc_hdr = &cmd_db_header->header[i];
+		if (!rsc_hdr->slv_id)
+			break;
+
+		ent = rsc_to_entry_header(rsc_hdr);
+		for (j = 0; j < le16_to_cpu(rsc_hdr->cnt); j++, ent++) {
+			if (memcmp(ent->id, query, sizeof(ent->id)) == 0) {
+				if (eh)
+					*eh = ent;
+				if (rh)
+					*rh = rsc_hdr;
+				return 0;
+			}
+		}
+	}
+
+	return -ENODEV;
+}
+
+/**
+ * cmd_db_read_addr() - Query command db for resource id address.
+ *
+ * @id: resource id to query for address
+ *
+ * Return: resource address on success, 0 on error
+ *
+ * This is used to retrieve resource address based on resource
+ * id.
+ */
+u32 cmd_db_read_addr(const char *id)
+{
+	int ret;
+	const struct entry_header *ent;
+
+	debug("%s(%s)\n", __func__, id);
+
+	if (!cmd_db_header) {
+		log_err("%s: Command DB not initialized\n", __func__);
+		return 0;
+	}
+
+	ret = cmd_db_get_header(id, &ent, NULL);
+
+	return ret < 0 ? 0 : le32_to_cpu(ent->addr);
+}
+EXPORT_SYMBOL_GPL(cmd_db_read_addr);
+
+int cmd_db_bind(struct udevice *dev)
+{
+	void __iomem *base;
+	ofnode node;
+
+	if (cmd_db_header)
+		return 0;
+
+	node = dev_ofnode(dev);
+
+	debug("%s(%s)\n", __func__, ofnode_get_name(node));
+
+	base = (void __iomem *)ofnode_get_addr(node);
+	if ((fdt_addr_t)base == FDT_ADDR_T_NONE) {
+		log_err("%s: Failed to read base address\n", __func__);
+		return -ENOENT;
+	}
+
+	cmd_db_header = base;
+	if (!cmd_db_magic_matches(cmd_db_header)) {
+		log_err("%s: Invalid Command DB Magic\n", __func__);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static const struct udevice_id cmd_db_ids[] = {
+	{ .compatible = "qcom,cmd-db" },
+	{ }
+};
+
+U_BOOT_DRIVER(qcom_cmd_db) = {
+	.name		= "qcom_cmd_db",
+	.id		= UCLASS_MISC,
+	.bind		= cmd_db_bind,
+	.of_match	= cmd_db_ids,
+};
+
+MODULE_DESCRIPTION("Qualcomm Technologies, Inc. Command DB Driver");
+MODULE_LICENSE("GPL v2");