[PATCH v2 02/15] soc: qcom: add support to APR bus driver

[srinivas.kandagatla@linaro.org]

From: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>

This patch adds support toi APR bus (Asynchronous Packet Router) driver.
ARP driver is made as a bus driver so that the apr devices can added removed
more dynamically depending on the state of the services on the dsp.
APR is used for communication between application processor and QDSP to
use services on QDSP like Audio and others.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
---
 drivers/soc/qcom/Kconfig        |   8 +
 drivers/soc/qcom/Makefile       |   1 +
 drivers/soc/qcom/apr.c          | 395 ++++++++++++++++++++++++++++++++++++++++
 include/linux/mod_devicetable.h |  13 ++
 include/linux/soc/qcom/apr.h    | 174 ++++++++++++++++++
 5 files changed, 591 insertions(+)
 create mode 100644 drivers/soc/qcom/apr.c
 create mode 100644 include/linux/soc/qcom/apr.h

diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig
index b81374bb6713..1daa39925dd4 100644
--- a/drivers/soc/qcom/Kconfig
+++ b/drivers/soc/qcom/Kconfig
@@ -97,4 +97,12 @@ config QCOM_WCNSS_CTRL
 	  Client driver for the WCNSS_CTRL SMD channel, used to download nv
 	  firmware to a newly booted WCNSS chip.
 
+config QCOM_APR
+	tristate "Qualcomm APR Bus (Asynchronous Packet Router)"
+	depends on (RPMSG_QCOM_SMD || RPMSG_QCOM_GLINK_RPM)
+	help
+          Enable APR IPC protocol support between
+          application processor and QDSP6. APR is
+          used by audio driver to configure QDSP6
+          ASM, ADM and AFE modules.
 endmenu
diff --git a/drivers/soc/qcom/Makefile b/drivers/soc/qcom/Makefile
index 40c56f67e94a..9daba7e6d20f 100644
--- a/drivers/soc/qcom/Makefile
+++ b/drivers/soc/qcom/Makefile
@@ -10,3 +10,4 @@ obj-$(CONFIG_QCOM_SMEM_STATE) += smem_state.o
 obj-$(CONFIG_QCOM_SMP2P)	+= smp2p.o
 obj-$(CONFIG_QCOM_SMSM)	+= smsm.o
 obj-$(CONFIG_QCOM_WCNSS_CTRL) += wcnss_ctrl.o
+obj-$(CONFIG_QCOM_APR) += apr.o
diff --git a/drivers/soc/qcom/apr.c b/drivers/soc/qcom/apr.c
new file mode 100644
index 000000000000..c6f3aa7a375b
--- /dev/null
+++ b/drivers/soc/qcom/apr.c
@@ -0,0 +1,395 @@
+/* SPDX-License-Identifier: GPL-2.0
+* Copyright (c) 2011-2016, The Linux Foundation
+* Copyright (c) 2017, Linaro Limited
+*/
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/spinlock.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+#include <linux/of_device.h>
+#include <linux/soc/qcom/apr.h>
+#include <linux/rpmsg.h>
+#include <linux/of.h>
+
+struct apr_data {
+	int (*get_data_src)(struct apr_hdr *hdr);
+	int dest_id;
+};
+
+struct apr {
+	struct rpmsg_endpoint *ch;
+	struct device *dev;
+	spinlock_t svcs_lock;
+	struct list_head svcs;
+	int dest_id;
+	const struct apr_data *data;
+};
+
+/* Static CORE service on the ADSP */
+static const struct apr_device_id core_svc_device_id =
+		ADSP_AUDIO_APR_DEV("CORE", APR_SVC_ADSP_CORE);
+
+/**
+ * apr_send_pkt() - Send a apr message from apr device
+ *
+ * @adev: Pointer to previously registered apr device.
+ * @buf: Pointer to buffer to send
+ *
+ * Return: Will be an negative on packet size on success.
+ */
+int apr_send_pkt(struct apr_device *adev, uint32_t *buf)
+{
+	struct apr *apr = dev_get_drvdata(adev->dev.parent);
+	struct apr_hdr *hdr;
+	unsigned long flags;
+	int ret;
+
+	spin_lock_irqsave(&adev->lock, flags);
+
+	hdr = (struct apr_hdr *)buf;
+	hdr->src_domain = APR_DOMAIN_APPS;
+	hdr->src_svc = adev->svc_id;
+	hdr->dest_domain = adev->domain_id;
+	hdr->dest_svc = adev->svc_id;
+
+	ret = rpmsg_send(apr->ch, buf, hdr->pkt_size);
+	if (ret) {
+		dev_err(&adev->dev, "Unable to send APR pkt %d\n",
+			hdr->pkt_size);
+	} else {
+		ret = hdr->pkt_size;
+	}
+
+	spin_unlock_irqrestore(&adev->lock, flags);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(apr_send_pkt);
+
+static void apr_dev_release(struct device *dev)
+{
+	struct apr_device *adev = to_apr_device(dev);
+
+	kfree(adev);
+}
+
+static int qcom_rpmsg_q6_callback(struct rpmsg_device *rpdev, void *buf,
+				  int len, void *priv, u32 addr)
+{
+	struct apr *apr = dev_get_drvdata(&rpdev->dev);
+	struct apr_client_data data;
+	struct apr_device *p, *c_svc = NULL;
+	struct apr_driver *adrv = NULL;
+	struct apr_hdr *hdr;
+	uint16_t hdr_size;
+	uint16_t msg_type;
+	uint16_t ver;
+	uint16_t src;
+	uint16_t svc;
+
+	if (!buf || len <= APR_HDR_SIZE) {
+		dev_err(apr->dev, "APR: Improper apr pkt received:%p %d\n",
+			buf, len);
+		return -EINVAL;
+	}
+
+	hdr = buf;
+	ver = APR_HDR_FIELD_VER(hdr->hdr_field);
+	if (ver > APR_PKT_VER + 1)
+		return -EINVAL;
+
+	hdr_size = APR_HDR_FIELD_SIZE_BYTES(hdr->hdr_field);
+	if (hdr_size < APR_HDR_SIZE) {
+		dev_err(apr->dev, "APR: Wrong hdr size:%d\n", hdr_size);
+		return -EINVAL;
+	}
+
+	if (hdr->pkt_size < APR_HDR_SIZE) {
+		dev_err(apr->dev, "APR: Wrong paket size\n");
+		return -EINVAL;
+	}
+
+	msg_type = APR_HDR_FIELD_MT(hdr->hdr_field);
+	if (msg_type >= APR_MSG_TYPE_MAX && msg_type != APR_BASIC_RSP_RESULT) {
+		dev_err(apr->dev, "APR: Wrong message type: %d\n", msg_type);
+		return -EINVAL;
+	}
+
+	if (hdr->src_domain >= APR_DOMAIN_MAX ||
+			hdr->dest_domain >= APR_DOMAIN_MAX ||
+			hdr->src_svc >= APR_SVC_MAX ||
+			hdr->dest_svc >= APR_SVC_MAX) {
+		dev_err(apr->dev, "APR: Wrong APR header\n");
+		return -EINVAL;
+	}
+
+	svc = hdr->dest_svc;
+	src = apr->data->get_data_src(hdr);
+	if (src == APR_DEST_MAX)
+		return -EINVAL;
+
+	spin_lock(&apr->svcs_lock);
+	list_for_each_entry(p, &apr->svcs, node) {
+		if (svc == p->svc_id) {
+			c_svc = p;
+			if (c_svc->dev.driver)
+				adrv = to_apr_driver(c_svc->dev.driver);
+			break;
+		}
+	}
+	spin_unlock(&apr->svcs_lock);
+
+	if (!adrv) {
+		dev_err(apr->dev, "APR: service is not registered\n");
+		return -EINVAL;
+	}
+
+	data.payload_size = hdr->pkt_size - hdr_size;
+	data.opcode = hdr->opcode;
+	data.src = src;
+	data.src_port = hdr->src_port;
+	data.dest_port = hdr->dest_port;
+	data.token = hdr->token;
+	data.msg_type = msg_type;
+
+	if (data.payload_size > 0)
+		data.payload = (char *)hdr + hdr_size;
+
+	adrv->callback(c_svc, &data);
+
+	return 0;
+}
+
+static const struct apr_device_id *apr_match(const struct apr_device_id *id,
+					       const struct apr_device *adev)
+{
+	while (id->domain_id != 0 || id->svc_id != 0) {
+		if (id->domain_id == adev->domain_id &&
+		    id->svc_id == adev->svc_id &&
+		    id->client_id == adev->client_id)
+			return id;
+		id++;
+	}
+	return NULL;
+}
+
+static int apr_device_match(struct device *dev, struct device_driver *drv)
+{
+	struct apr_device *adev = to_apr_device(dev);
+	struct apr_driver *adrv = to_apr_driver(drv);
+
+	return !!apr_match(adrv->id_table, adev);
+}
+
+static int apr_device_probe(struct device *dev)
+{
+	struct apr_device	*adev;
+	struct apr_driver	*adrv;
+	int ret = 0;
+
+	adev = to_apr_device(dev);
+	adrv = to_apr_driver(dev->driver);
+
+	ret = adrv->probe(adev);
+
+	return ret;
+}
+
+static int apr_device_remove(struct device *dev)
+{
+	struct apr_device *adev = to_apr_device(dev);
+	struct apr_driver *adrv;
+	struct apr *apr = dev_get_drvdata(adev->dev.parent);
+
+	if (dev->driver) {
+		adrv = to_apr_driver(dev->driver);
+		if (adrv->remove)
+			adrv->remove(adev);
+		spin_lock(&apr->svcs_lock);
+		list_del(&adev->node);
+		spin_unlock(&apr->svcs_lock);
+	}
+
+	return 0;
+}
+
+struct bus_type aprbus_type = {
+	.name		= "aprbus",
+	.match		= apr_device_match,
+	.probe		= apr_device_probe,
+	.remove		= apr_device_remove,
+};
+EXPORT_SYMBOL_GPL(aprbus_type);
+
+/**
+ * apr_add_device() - Add a new apr device
+ *
+ * @dev: Pointer to apr device.
+ * @id: Pointer to apr device id to add.
+ *
+ * Return: Will be an negative on error or a zero on success.
+ */
+int apr_add_device(struct device *dev, const struct apr_device_id *id)
+{
+	struct apr *apr = dev_get_drvdata(dev);
+	struct apr_device *adev = NULL;
+
+	if (!apr)
+		return -EINVAL;
+
+	adev = kzalloc(sizeof(*adev), GFP_KERNEL);
+	if (!adev)
+		return -ENOMEM;
+
+	spin_lock_init(&adev->lock);
+
+	adev->svc_id = id->svc_id;
+	adev->dest_id = apr->dest_id;
+	adev->client_id = id->client_id;
+	adev->domain_id = id->domain_id;
+	adev->version = id->svc_version;
+
+	adev->dev.bus = &aprbus_type;
+	adev->dev.parent = dev;
+	adev->dev.release = apr_dev_release;
+	adev->dev.driver = NULL;
+
+	dev_set_name(&adev->dev, "apr:%s:%x:%x:%x", id->name, id->domain_id,
+				 id->svc_id, id->client_id);
+
+	spin_lock(&apr->svcs_lock);
+	list_add_tail(&adev->node, &apr->svcs);
+	spin_unlock(&apr->svcs_lock);
+
+	return device_register(&adev->dev);
+}
+EXPORT_SYMBOL_GPL(apr_add_device);
+
+static int qcom_rpmsg_q6_probe(struct rpmsg_device *rpdev)
+{
+	struct device *dev = &rpdev->dev;
+	struct apr *apr;
+
+	apr = devm_kzalloc(dev, sizeof(*apr), GFP_KERNEL);
+	if (!apr)
+		return -ENOMEM;
+
+	apr->data = of_device_get_match_data(dev);
+	if (!apr->data)
+		return -ENODEV;
+
+	apr->dest_id = apr->data->dest_id;
+	dev_set_drvdata(dev, apr);
+	apr->ch = rpdev->ept;
+	apr->dev = dev;
+	INIT_LIST_HEAD(&apr->svcs);
+
+	/* register core service */
+	apr_add_device(dev, &core_svc_device_id);
+
+	return 0;
+}
+
+static int apr_remove_device(struct device *dev, void *null)
+{
+	struct apr_device *adev = to_apr_device(dev);
+
+	device_unregister(&adev->dev);
+
+	return 0;
+}
+
+static void qcom_rpmsg_q6_remove(struct rpmsg_device *rpdev)
+{
+	device_for_each_child(&rpdev->dev, NULL, apr_remove_device);
+}
+
+static int apr_v2_get_data_src(struct apr_hdr *hdr)
+{
+	if (hdr->src_domain == APR_DOMAIN_MODEM)
+		return APR_DEST_MODEM;
+	else if (hdr->src_domain == APR_DOMAIN_ADSP)
+		return APR_DEST_QDSP6;
+
+	return APR_DEST_MAX;
+}
+
+/*
+ * __apr_driver_register() - Client driver registration with aprbus
+ *
+ * @drv:Client driver to be associated with client-device.
+ * @owner: owning module/driver
+ *
+ * This API will register the client driver with the aprbus
+ * It is called from the driver's module-init function.
+ */
+int __apr_driver_register(struct apr_driver *drv, struct module *owner)
+{
+	/* ID table is mandatory to match the devices to probe */
+	if (!drv->id_table)
+		return -EINVAL;
+
+	drv->driver.bus = &aprbus_type;
+	drv->driver.owner = owner;
+
+	return driver_register(&drv->driver);
+}
+EXPORT_SYMBOL_GPL(__apr_driver_register);
+
+/*
+ * apr_driver_unregister() - Undo effect of apr_driver_register
+ *
+ * @drv: Client driver to be unregistered
+ */
+void apr_driver_unregister(struct apr_driver *drv)
+{
+	driver_unregister(&drv->driver);
+}
+EXPORT_SYMBOL_GPL(apr_driver_unregister);
+
+static const struct apr_data apr_v2_data = {
+	.get_data_src = apr_v2_get_data_src,
+	.dest_id = APR_DEST_QDSP6,
+};
+
+static const struct of_device_id qcom_rpmsg_q6_of_match[] = {
+	{ .compatible = "qcom,apr-msm8996", .data = &apr_v2_data},
+	{}
+};
+
+static struct rpmsg_driver qcom_rpmsg_q6_driver = {
+	.probe = qcom_rpmsg_q6_probe,
+	.remove = qcom_rpmsg_q6_remove,
+	.callback = qcom_rpmsg_q6_callback,
+	.drv = {
+		.name = "qcom_rpmsg_q6",
+		.owner = THIS_MODULE,
+		.of_match_table = qcom_rpmsg_q6_of_match,
+		},
+};
+
+static int __init apr_init(void)
+{
+	int ret;
+
+	ret = register_rpmsg_driver(&qcom_rpmsg_q6_driver);
+	if (!ret)
+		return bus_register(&aprbus_type);
+
+	return ret;
+}
+
+static void __exit apr_exit(void)
+{
+	bus_unregister(&aprbus_type);
+	unregister_rpmsg_driver(&qcom_rpmsg_q6_driver);
+}
+
+subsys_initcall(apr_init);
+module_exit(apr_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Qualcomm APR Bus");
diff --git a/include/linux/mod_devicetable.h b/include/linux/mod_devicetable.h
index abb6dc2ebbf8..068d215c3be6 100644
--- a/include/linux/mod_devicetable.h
+++ b/include/linux/mod_devicetable.h
@@ -452,6 +452,19 @@ struct spi_device_id {
 	kernel_ulong_t driver_data;	/* Data private to the driver */
 };
 
+
+#define APR_NAME_SIZE	32
+#define APR_MODULE_PREFIX "apr:"
+
+struct apr_device_id {
+	char name[APR_NAME_SIZE];
+	__u32 domain_id;
+	__u32 svc_id;
+	__u32 client_id;
+	__u32 svc_version;
+	kernel_ulong_t driver_data;	/* Data private to the driver */
+};
+
 #define SPMI_NAME_SIZE	32
 #define SPMI_MODULE_PREFIX "spmi:"
 
diff --git a/include/linux/soc/qcom/apr.h b/include/linux/soc/qcom/apr.h
new file mode 100644
index 000000000000..8620289c34ab
--- /dev/null
+++ b/include/linux/soc/qcom/apr.h
@@ -0,0 +1,174 @@
+/* SPDX-License-Identifier: GPL-2.0
+* Copyright (c) 2011-2016, The Linux Foundation
+* Copyright (c) 2017, Linaro Limited
+*/
+
+#ifndef __APR_H_
+#define __APR_H_
+
+#include <linux/spinlock.h>
+#include <linux/device.h>
+#include <linux/mod_devicetable.h>
+/* APR Client IDs */
+#define APR_CLIENT_AUDIO	0x0
+#define APR_CLIENT_VOICE	0x1
+#define APR_CLIENT_MAX		0x2
+
+#define APR_DL_SMD    0
+#define APR_DL_MAX    1
+
+#define APR_DEST_MODEM 0
+#define APR_DEST_QDSP6 1
+#define APR_DEST_MAX   2
+#define APR_MAX_BUF   8192
+
+#define APR_HDR_LEN(hdr_len) ((hdr_len)/4)
+#define APR_PKT_SIZE(hdr_len, payload_len) ((hdr_len) + (payload_len))
+#define APR_HDR_FIELD(msg_type, hdr_len, ver)\
+	(((msg_type & 0x3) << 8) | ((hdr_len & 0xF) << 4) | (ver & 0xF))
+
+#define APR_HDR_SIZE sizeof(struct apr_hdr)
+#define APR_SEQ_CMD_HDR_FIELD APR_HDR_FIELD(APR_MSG_TYPE_SEQ_CMD, \
+					    APR_HDR_LEN(APR_HDR_SIZE), \
+					    APR_PKT_VER)
+
+/* Version */
+#define APR_PKT_VER		0x0
+
+/* Command and Response Types */
+#define APR_MSG_TYPE_EVENT	0x0
+#define APR_MSG_TYPE_CMD_RSP	0x1
+#define APR_MSG_TYPE_SEQ_CMD	0x2
+#define APR_MSG_TYPE_NSEQ_CMD	0x3
+#define APR_MSG_TYPE_MAX	0x04
+
+/* APR Basic Response Message */
+#define APR_BASIC_RSP_RESULT 0x000110E8
+#define APR_RSP_ACCEPTED     0x000100BE
+
+/* Domain IDs */
+#define APR_DOMAIN_SIM	0x1
+#define APR_DOMAIN_PC		0x2
+#define APR_DOMAIN_MODEM	0x3
+#define APR_DOMAIN_ADSP	0x4
+#define APR_DOMAIN_APPS	0x5
+#define APR_DOMAIN_MAX	0x6
+
+/* ADSP service IDs */
+#define APR_SVC_TEST_CLIENT     0x2
+#define APR_SVC_ADSP_CORE	0x3
+#define APR_SVC_AFE		0x4
+#define APR_SVC_VSM		0x5
+#define APR_SVC_VPM		0x6
+#define APR_SVC_ASM		0x7
+#define APR_SVC_ADM		0x8
+#define APR_SVC_ADSP_MVM	0x09
+#define APR_SVC_ADSP_CVS	0x0A
+#define APR_SVC_ADSP_CVP	0x0B
+#define APR_SVC_USM		0x0C
+#define APR_SVC_LSM		0x0D
+#define APR_SVC_VIDC		0x16
+#define APR_SVC_MAX		0x17
+
+/* Modem Service IDs */
+#define APR_SVC_MVS		0x3
+#define APR_SVC_MVM		0x4
+#define APR_SVC_CVS		0x5
+#define APR_SVC_CVP		0x6
+#define APR_SVC_SRD		0x7
+
+/* APR Port IDs */
+#define APR_MAX_PORTS		0x80
+#define APR_NAME_MAX		0x40
+#define RESET_EVENTS		0x000130D7
+
+/* hdr field Ver [0:3], Size [4:7], Message type [8:10] */
+#define APR_HDR_FIELD_VER(h)		(h & 0x000F)
+#define APR_HDR_FIELD_SIZE(h)		((h & 0x00F0) >> 4)
+#define APR_HDR_FIELD_SIZE_BYTES(h)	(((h & 0x00F0) >> 4) * 4)
+#define APR_HDR_FIELD_MT(h)		((h & 0x0300) >> 8)
+
+struct apr_hdr {
+	uint16_t hdr_field;
+	uint16_t pkt_size;
+	uint8_t src_svc;
+	uint8_t src_domain;
+	uint16_t src_port;
+	uint8_t dest_svc;
+	uint8_t dest_domain;
+	uint16_t dest_port;
+	uint32_t token;
+	uint32_t opcode;
+};
+
+struct apr_client_data {
+	uint16_t payload_size;
+	uint16_t hdr_len;
+	uint16_t msg_type;
+	uint16_t src;
+	uint16_t dest_svc;
+	uint16_t src_port;
+	uint16_t dest_port;
+	uint32_t token;
+	uint32_t opcode;
+	void *payload;
+};
+
+#define ADSP_AUDIO_APR_DEV(name, id) \
+	{name, APR_DOMAIN_ADSP, id, APR_CLIENT_AUDIO}
+
+/* Bits 0 to 15 -- Minor version,  Bits 16 to 31 -- Major version */
+
+#define APR_SVC_MAJOR_VERSION(v)	((v >> 16) & 0xFF)
+#define APR_SVC_MINOR_VERSION(v)	(v & 0xFF)
+
+struct apr_device {
+	struct device	dev;
+	uint16_t	svc_id;
+	uint16_t	dest_id;
+	uint16_t	client_id;
+	uint16_t	domain_id;
+	uint16_t	version;
+
+	spinlock_t	lock;
+	struct list_head node;
+};
+
+
+#define to_apr_device(d) container_of(d, struct apr_device, dev)
+
+struct apr_driver {
+	int	(*probe)(struct apr_device *sl);
+	int	(*remove)(struct apr_device *sl);
+	int	(*callback)(struct apr_device *a, struct apr_client_data *d);
+	struct device_driver		driver;
+	const struct apr_device_id	*id_table;
+};
+
+#define to_apr_driver(d) container_of(d, struct apr_driver, driver)
+
+/*
+ * use a macro to avoid include chaining to get THIS_MODULE
+ */
+#define apr_driver_register(drv) __apr_driver_register(drv, THIS_MODULE)
+
+int __apr_driver_register(struct apr_driver *drv, struct module *owner);
+void apr_driver_unregister(struct apr_driver *drv);
+int apr_add_device(struct device *dev, const struct apr_device_id *id);
+
+/**
+ * module_apr_driver() - Helper macro for registering a aprbus driver
+ * @__aprbus_driver: aprbus_driver struct
+ *
+ * Helper macro for aprbus drivers which do not do anything special in
+ * module init/exit. This eliminates a lot of boilerplate. Each module
+ * may only use this macro once, and calling it replaces module_init()
+ * and module_exit()
+ */
+#define module_apr_driver(__apr_driver) \
+	module_driver(__apr_driver, apr_driver_register, \
+			apr_driver_unregister)
+
+int apr_send_pkt(struct apr_device *adev, uint32_t *buf);
+
+#endif /* __APR_H_ */
-- 
2.15.0