This patch adds basic driver model for Qualcomm FastRPC driver which
implements an IPC (Inter-Processor Communication) mechanism that
allows for clients to transparently make remote method invocations
across processor boundaries.
Each DSP rpmsg channel is represented as fastrpc channel context and
is exposed as a character device for userspace interface.
Each compute context bank is represented as fastrpc-session-context,
which are dynamically managed by the channel context char device.
Co-developed-by: Thierry Escande <thierry.escande@xxxxxxxxxx>
Signed-off-by: Thierry Escande <thierry.escande@xxxxxxxxxx>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>
---
drivers/misc/Kconfig | 10 ++
drivers/misc/Makefile | 1 +
drivers/misc/fastrpc.c | 322 +++++++++++++++++++++++++++++++++++++++++
3 files changed, 333 insertions(+)
create mode 100644 drivers/misc/fastrpc.c
diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index f417b06e11c5..7e0726253755 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -295,6 +295,16 @@ config QCOM_COINCELL
to maintain PMIC register and RTC state in the absence of
external power.
+config QCOM_FASTRPC
+ tristate "Qualcomm FastRPC"
+ depends on ARCH_QCOM || COMPILE_TEST
+ depends on RPMSG
+ help
+ Provides a communication mechanism that allows for clients to
+ make remote method invocations across processor boundary to
+ applications DSP processor. Say M if you want to enable this
+ module.
+
config SGI_GRU
tristate "SGI GRU driver"
depends on X86_UV && SMP
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index e39ccbbc1b3a..623d002c59ce 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -18,6 +18,7 @@ obj-$(CONFIG_TIFM_CORE) += tifm_core.o
obj-$(CONFIG_TIFM_7XX1) += tifm_7xx1.o
obj-$(CONFIG_PHANTOM) += phantom.o
obj-$(CONFIG_QCOM_COINCELL) += qcom-coincell.o
+obj-$(CONFIG_QCOM_FASTRPC) += fastrpc.o
obj-$(CONFIG_SENSORS_BH1770) += bh1770glc.o
obj-$(CONFIG_SENSORS_APDS990X) += apds990x.o
obj-$(CONFIG_SGI_IOC4) += ioc4.o
diff --git a/drivers/misc/fastrpc.c b/drivers/misc/fastrpc.c
new file mode 100644
index 000000000000..10b93fd5659a
--- /dev/null
+++ b/drivers/misc/fastrpc.c
@@ -0,0 +1,322 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2011-2018, The Linux Foundation. All rights reserved.
+// Copyright (c) 2018, Linaro Limited
+
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/idr.h>
+#include <linux/list.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/rpmsg.h>
+#include <linux/scatterlist.h>
+#include <linux/slab.h>
+
+#define ADSP_DOMAIN_ID (0)
+#define MDSP_DOMAIN_ID (1)
+#define SDSP_DOMAIN_ID (2)
+#define CDSP_DOMAIN_ID (3)
+#define FASTRPC_DEV_MAX 4 /* adsp, mdsp, slpi, cdsp*/
+#define FASTRPC_MAX_SESSIONS 9 /*8 compute, 1 cpz*/
+#define FASTRPC_CTX_MAX (256)
+#define FASTRPC_CTXID_MASK (0xFF0)
+#define FASTRPC_DEVICE_NAME "fastrpc"
+
+#define miscdev_to_cctx(d) container_of(d, struct fastrpc_channel_ctx, miscdev)
+
+static const char *domains[FASTRPC_DEV_MAX] = { "adsp", "mdsp",
+ "sdsp", "cdsp"};
+
+struct fastrpc_session_ctx {
+ struct device *dev;
+ int sid;
+ bool used;
+ bool valid;
+};
+
+struct fastrpc_channel_ctx {
+ int domain_id;
+ int sesscount;
+ struct rpmsg_device *rpdev;
+ struct fastrpc_session_ctx session[FASTRPC_MAX_SESSIONS];
+ spinlock_t lock;
+ struct idr ctx_idr;
+ struct list_head users;
+ struct miscdevice miscdev;
+};
+
+struct fastrpc_user {
+ struct list_head user;
+ struct list_head maps;
+ struct list_head pending;
+
+ struct fastrpc_channel_ctx *cctx;
+ struct fastrpc_session_ctx *sctx;
+
+ int tgid;
+ int pd;
+ /* Lock for lists */
+ spinlock_t lock;
+ /* lock for allocations */
+ struct mutex mutex;
+};
+
+static struct fastrpc_session_ctx *fastrpc_session_alloc(
+ struct fastrpc_channel_ctx *cctx)
+{
+ struct fastrpc_session_ctx *session = NULL;
+ int i;
+
+ spin_lock(&cctx->lock);
+ for (i = 0; i < cctx->sesscount; i++) {
+ if (!cctx->session[i].used && cctx->session[i].valid) {
+ cctx->session[i].used = true;
+ session = &cctx->session[i];
+ break;
+ }
+ }
+ spin_unlock(&cctx->lock);
+
+ return session;
+}
+
+static void fastrpc_session_free(struct fastrpc_channel_ctx *cctx,
+ struct fastrpc_session_ctx *session)
+{
+ spin_lock(&cctx->lock);
+ session->used = false;
+ spin_unlock(&cctx->lock);
+}
+
+static int fastrpc_device_release(struct inode *inode, struct file *file)
+{
+ struct fastrpc_user *fl = (struct fastrpc_user *)file->private_data;
+ struct fastrpc_channel_ctx *cctx = fl->cctx;
+
+ spin_lock(&cctx->lock);
+ list_del(&fl->user);
+ spin_unlock(&cctx->lock);
+
+ fastrpc_session_free(cctx, fl->sctx);
+
+ mutex_destroy(&fl->mutex);
+ kfree(fl);
+ file->private_data = NULL;
+
+ return 0;
+}
+
+static int fastrpc_device_open(struct inode *inode, struct file *filp)
+{
+ struct fastrpc_channel_ctx *cctx = miscdev_to_cctx(filp->private_data);
+ struct fastrpc_user *fl = NULL;
+
+ fl = kzalloc(sizeof(*fl), GFP_KERNEL);
+ if (!fl)
+ return -ENOMEM;
+
+ filp->private_data = fl;
+ spin_lock_init(&fl->lock);
+ mutex_init(&fl->mutex);
+ INIT_LIST_HEAD(&fl->pending);
+ INIT_LIST_HEAD(&fl->maps);
+ INIT_LIST_HEAD(&fl->user);
+ fl->tgid = current->tgid;
+ fl->cctx = cctx;
+ spin_lock(&cctx->lock);
+ list_add_tail(&fl->user, &cctx->users);
+ spin_unlock(&cctx->lock);
+ fl->sctx = fastrpc_session_alloc(cctx);
+
+ return 0;
+}
+
+static const struct file_operations fastrpc_fops = {
+ .open = fastrpc_device_open,
+ .release = fastrpc_device_release,
+};
+
+static int fastrpc_cb_probe(struct platform_device *pdev)
+{
+ struct fastrpc_channel_ctx *cctx;
+ struct fastrpc_session_ctx *sess;
+ struct device *dev = &pdev->dev;
+ int i, sessions = 0;
+
+ cctx = dev_get_drvdata(dev->parent);
+ if (!cctx)
+ return -EINVAL;
+
+ of_property_read_u32(dev->of_node, "qcom,nsessions", &sessions);
+
+ spin_lock(&cctx->lock);
+ sess = &cctx->session[cctx->sesscount];
+ sess->used = false;
+ sess->valid = true;
+ sess->dev = dev;
+ dev_set_drvdata(dev, sess);
+
+ if (of_property_read_u32(dev->of_node, "reg", &sess->sid))
+ dev_info(dev, "FastRPC Session ID not specified in DT\n");
+
+ if (sessions > 0) {
+ struct fastrpc_session_ctx *dup_sess;
+
+ for (i = 1; i < sessions; i++) {
+ if (cctx->sesscount++ >= FASTRPC_MAX_SESSIONS)
+ break;
+ dup_sess = &cctx->session[cctx->sesscount];
+ memcpy(dup_sess, sess, sizeof(*dup_sess));
+ }
+ }
+ cctx->sesscount++;
+ spin_unlock(&cctx->lock);
+ dma_set_mask(dev, DMA_BIT_MASK(32));
+
+ return 0;
+}
+
+static int fastrpc_cb_remove(struct platform_device *pdev)
+{
+ struct fastrpc_channel_ctx *cctx = dev_get_drvdata(pdev->dev.parent);
+ struct fastrpc_session_ctx *sess = dev_get_drvdata(&pdev->dev);
+ int i;
+
+ spin_lock(&cctx->lock);
+ for (i = 1; i < FASTRPC_MAX_SESSIONS; i++) {
+ if (cctx->session[i].sid == sess->sid) {
+ cctx->session[i].valid = false;
+ cctx->sesscount--;
+ }
+ }
+ spin_unlock(&cctx->lock);
+
+ return 0;
+}
+
+static const struct of_device_id fastrpc_match_table[] = {
+ { .compatible = "qcom,fastrpc-compute-cb", },
+ {}
+};
+
+static struct platform_driver fastrpc_cb_driver = {
+ .probe = fastrpc_cb_probe,
+ .remove = fastrpc_cb_remove,
+ .driver = {
+ .name = "qcom,fastrpc-cb",
+ .of_match_table = fastrpc_match_table,
+ .suppress_bind_attrs = true,
+ },
+};
+
+static int fastrpc_rpmsg_probe(struct rpmsg_device *rpdev)
+{
+ struct device *rdev = &rpdev->dev;
+ struct fastrpc_channel_ctx *data;
+ int i, err, domain_id = -1;
+ const char *domain;
+
+ data = devm_kzalloc(rdev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ err = of_property_read_string(rdev->of_node, "label", &domain);
+ if (err) {
+ dev_info(rdev, "FastRPC Domain not specified in DT\n");
+ return err;
+ }
+
+ for (i = 0; i <= CDSP_DOMAIN_ID; i++) {
+ if (!strcmp(domains[i], domain)) {
+ domain_id = i;
+ break;
+ }
+ }
+
+ if (domain_id < 0) {
+ dev_info(rdev, "FastRPC Invalid Domain ID %d\n", domain_id);
+ return -EINVAL;
+ }
+
+ data->miscdev.minor = MISC_DYNAMIC_MINOR;
+ data->miscdev.name = kasprintf(GFP_KERNEL, "fastrpc-%s",
+ domains[domain_id]);
+ data->miscdev.fops = &fastrpc_fops;
+ err = misc_register(&data->miscdev);
+ if (err)
+ return err;
+
+ dev_set_drvdata(&rpdev->dev, data);
+ dma_set_mask_and_coherent(rdev, DMA_BIT_MASK(32));
+ INIT_LIST_HEAD(&data->users);
+ spin_lock_init(&data->lock);
+ idr_init(&data->ctx_idr);
+ data->domain_id = domain_id;
+ data->rpdev = rpdev;
+
+ return of_platform_populate(rdev->of_node, NULL, NULL, rdev);
+}
+
+static void fastrpc_rpmsg_remove(struct rpmsg_device *rpdev)
+{
+ struct fastrpc_channel_ctx *cctx = dev_get_drvdata(&rpdev->dev);
+
+ misc_deregister(&cctx->miscdev);
+ of_platform_depopulate(&rpdev->dev);
+ kfree(cctx);
+}
+
+static int fastrpc_rpmsg_callback(struct rpmsg_device *rpdev, void *data,
+ int len, void *priv, u32 addr)
+{
+ return 0;
+}
+
+static const struct of_device_id fastrpc_rpmsg_of_match[] = {
+ { .compatible = "qcom,fastrpc" },
+ { },
+};
+MODULE_DEVICE_TABLE(of, fastrpc_rpmsg_of_match);
+
+static struct rpmsg_driver fastrpc_driver = {
+ .probe = fastrpc_rpmsg_probe,
+ .remove = fastrpc_rpmsg_remove,
+ .callback = fastrpc_rpmsg_callback,
+ .drv = {
+ .name = "qcom,fastrpc",
+ .of_match_table = fastrpc_rpmsg_of_match,
+ },
+};
+
+static int fastrpc_init(void)
+{
+ int ret;
+
+ ret = platform_driver_register(&fastrpc_cb_driver);
+ if (ret < 0) {
+ pr_err("fastrpc: failed to register cb driver\n");
+ return ret;
+ }
+
+ ret = register_rpmsg_driver(&fastrpc_driver);
+ if (ret < 0) {
+ pr_err("fastrpc: failed to register rpmsg driver\n");
+ platform_driver_unregister(&fastrpc_cb_driver);
+ return ret;
+ }
+
+ return 0;
+}
+module_init(fastrpc_init);
+
+static void fastrpc_exit(void)
+{
+ platform_driver_unregister(&fastrpc_cb_driver);
+ unregister_rpmsg_driver(&fastrpc_driver);
+}
+module_exit(fastrpc_exit);
+
+MODULE_LICENSE("GPL v2");
--
2.20.1
