rpmsg: glink: Introduce glink smem based transport
authorBjorn Andersson <bjorn.andersson@linaro.org>
Thu, 24 Aug 2017 07:21:30 +0000 (12:51 +0530)
committerBjorn Andersson <bjorn.andersson@linaro.org>
Wed, 30 Aug 2017 03:33:57 +0000 (20:33 -0700)
The glink protocol supports different types of transports (shared
memory). With the core protocol remaining the same, the way the
transport's memory is probed and accessed is different. So add support
for glink's smem based transports.

Adding a new smem transport register function and the fifo accessors for
the same.

Acked-by: Arun Kumar Neelakantam <aneela@codeaurora.org>
Signed-off-by: Sricharan R <sricharan@codeaurora.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
drivers/rpmsg/Kconfig
drivers/rpmsg/Makefile
drivers/rpmsg/qcom_glink_native.c
drivers/rpmsg/qcom_glink_native.h
drivers/rpmsg/qcom_glink_smem.c [new file with mode: 0644]
include/linux/rpmsg/qcom_glink.h [new file with mode: 0644]

index 4218570279e0802e44f6bc79cd7c53b5a4d5fe7c..0fe6eac465121d6bbf7c8c1ce9a8d06d21c0a7a6 100644 (file)
@@ -27,6 +27,16 @@ config RPMSG_QCOM_GLINK_RPM
          which serves as a channel for communication with the RPM in GLINK
          enabled systems.
 
+config RPMSG_QCOM_GLINK_SMEM
+       tristate "Qualcomm SMEM Glink driver"
+       select RPMSG_QCOM_GLINK_NATIVE
+       depends on MAILBOX
+       depends on QCOM_SMEM
+       help
+         Say y here to enable support for the GLINK SMEM communication driver,
+         which provides support for using the GLINK communication protocol
+         over SMEM.
+
 config RPMSG_QCOM_SMD
        tristate "Qualcomm Shared Memory Driver (SMD)"
        depends on QCOM_SMEM
index 09a756c33e71c94631d1558742fd77c553d6a557..c71f4ab1ae1707e3d305cf1380818f7459bcb9cc 100644 (file)
@@ -2,5 +2,6 @@ obj-$(CONFIG_RPMSG)             += rpmsg_core.o
 obj-$(CONFIG_RPMSG_CHAR)       += rpmsg_char.o
 obj-$(CONFIG_RPMSG_QCOM_GLINK_RPM) += qcom_glink_rpm.o
 obj-$(CONFIG_RPMSG_QCOM_GLINK_NATIVE) += qcom_glink_native.o
+obj-$(CONFIG_RPMSG_QCOM_GLINK_SMEM) += qcom_glink_smem.o
 obj-$(CONFIG_RPMSG_QCOM_SMD)   += qcom_smd.o
 obj-$(CONFIG_RPMSG_VIRTIO)     += virtio_rpmsg_bus.o
index 21adde34725b78b83fcd2c29b346935ce81a5cf8..50a8008036883633357b6d29aab2156ec94e2a85 100644 (file)
@@ -1010,3 +1010,8 @@ void qcom_glink_native_remove(struct qcom_glink *glink)
        idr_destroy(&glink->rcids);
        mbox_free_channel(glink->mbox_chan);
 }
+
+void qcom_glink_native_unregister(struct qcom_glink *glink)
+{
+       device_unregister(glink->dev);
+}
index d5627a495c008428da768d05c8e2a486e813b027..197bb9da2c65fa147cdc3d22ae551cc5c6f1243f 100644 (file)
@@ -35,4 +35,5 @@ struct qcom_glink *qcom_glink_native_probe(struct device *dev,
                                           struct qcom_glink_pipe *tx);
 void qcom_glink_native_remove(struct qcom_glink *glink);
 
+void qcom_glink_native_unregister(struct qcom_glink *glink);
 #endif
diff --git a/drivers/rpmsg/qcom_glink_smem.c b/drivers/rpmsg/qcom_glink_smem.c
new file mode 100644 (file)
index 0000000..19179a1
--- /dev/null
@@ -0,0 +1,311 @@
+/*
+ * Copyright (c) 2016, Linaro Ltd
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/mfd/syscon.h>
+#include <linux/slab.h>
+#include <linux/rpmsg.h>
+#include <linux/idr.h>
+#include <linux/circ_buf.h>
+#include <linux/soc/qcom/smem.h>
+#include <linux/sizes.h>
+#include <linux/delay.h>
+#include <linux/regmap.h>
+#include <linux/workqueue.h>
+#include <linux/list.h>
+
+#include <linux/delay.h>
+#include <linux/rpmsg.h>
+#include <linux/rpmsg/qcom_glink.h>
+
+#include "qcom_glink_native.h"
+
+#define FIFO_FULL_RESERVE 8
+#define FIFO_ALIGNMENT 8
+#define TX_BLOCKED_CMD_RESERVE 8 /* size of struct read_notif_request */
+
+#define SMEM_GLINK_NATIVE_XPRT_DESCRIPTOR      478
+#define SMEM_GLINK_NATIVE_XPRT_FIFO_0          479
+#define SMEM_GLINK_NATIVE_XPRT_FIFO_1          480
+
+struct glink_smem_pipe {
+       struct qcom_glink_pipe native;
+
+       __le32 *tail;
+       __le32 *head;
+
+       void *fifo;
+
+       int remote_pid;
+};
+
+#define to_smem_pipe(p) container_of(p, struct glink_smem_pipe, native)
+
+static size_t glink_smem_rx_avail(struct qcom_glink_pipe *np)
+{
+       struct glink_smem_pipe *pipe = to_smem_pipe(np);
+       size_t len;
+       void *fifo;
+       u32 head;
+       u32 tail;
+
+       if (!pipe->fifo) {
+               fifo = qcom_smem_get(pipe->remote_pid,
+                                    SMEM_GLINK_NATIVE_XPRT_FIFO_1, &len);
+               if (IS_ERR(fifo)) {
+                       pr_err("failed to acquire RX fifo handle: %ld\n",
+                              PTR_ERR(fifo));
+                       return 0;
+               }
+
+               pipe->fifo = fifo;
+               pipe->native.length = len;
+       }
+
+       head = le32_to_cpu(*pipe->head);
+       tail = le32_to_cpu(*pipe->tail);
+
+       if (head < tail)
+               return pipe->native.length - tail + head;
+       else
+               return head - tail;
+}
+
+static void glink_smem_rx_peak(struct qcom_glink_pipe *np,
+                              void *data, size_t count)
+{
+       struct glink_smem_pipe *pipe = to_smem_pipe(np);
+       size_t len;
+       u32 tail;
+
+       tail = le32_to_cpu(*pipe->tail);
+
+       len = min_t(size_t, count, pipe->native.length - tail);
+       if (len) {
+               __ioread32_copy(data, pipe->fifo + tail,
+                               len / sizeof(u32));
+       }
+
+       if (len != count) {
+               __ioread32_copy(data + len, pipe->fifo,
+                               (count - len) / sizeof(u32));
+       }
+}
+
+static void glink_smem_rx_advance(struct qcom_glink_pipe *np,
+                                 size_t count)
+{
+       struct glink_smem_pipe *pipe = to_smem_pipe(np);
+       u32 tail;
+
+       tail = le32_to_cpu(*pipe->tail);
+
+       tail += count;
+       if (tail > pipe->native.length)
+               tail -= pipe->native.length;
+
+       *pipe->tail = cpu_to_le32(tail);
+}
+
+static size_t glink_smem_tx_avail(struct qcom_glink_pipe *np)
+{
+       struct glink_smem_pipe *pipe = to_smem_pipe(np);
+       u32 head;
+       u32 tail;
+       u32 avail;
+
+       head = le32_to_cpu(*pipe->head);
+       tail = le32_to_cpu(*pipe->tail);
+
+       if (tail <= head)
+               avail = pipe->native.length - head + tail;
+       else
+               avail = tail - head;
+
+       if (avail < (FIFO_FULL_RESERVE + TX_BLOCKED_CMD_RESERVE))
+               avail = 0;
+       else
+               avail -= FIFO_FULL_RESERVE + TX_BLOCKED_CMD_RESERVE;
+
+       return avail;
+}
+
+static unsigned int glink_smem_tx_write_one(struct glink_smem_pipe *pipe,
+                                           unsigned int head,
+                                           const void *data, size_t count)
+{
+       size_t len;
+
+       len = min_t(size_t, count, pipe->native.length - head);
+       if (len)
+               memcpy(pipe->fifo + head, data, len);
+
+       if (len != count)
+               memcpy(pipe->fifo, data + len, count - len);
+
+       head += count;
+       if (head >= pipe->native.length)
+               head -= pipe->native.length;
+
+       return head;
+}
+
+static void glink_smem_tx_write(struct qcom_glink_pipe *glink_pipe,
+                               const void *hdr, size_t hlen,
+                               const void *data, size_t dlen)
+{
+       struct glink_smem_pipe *pipe = to_smem_pipe(glink_pipe);
+       unsigned int head;
+
+       head = le32_to_cpu(*pipe->head);
+
+       head = glink_smem_tx_write_one(pipe, head, hdr, hlen);
+       head = glink_smem_tx_write_one(pipe, head, data, dlen);
+
+       /* Ensure head is always aligned to 8 bytes */
+       head = ALIGN(head, 8);
+       if (head >= pipe->native.length)
+               head -= pipe->native.length;
+
+       *pipe->head = cpu_to_le32(head);
+}
+
+static void qcom_glink_smem_release(struct device *dev)
+{
+       kfree(dev);
+}
+
+struct qcom_glink *qcom_glink_smem_register(struct device *parent,
+                                           struct device_node *node)
+{
+       struct glink_smem_pipe *rx_pipe;
+       struct glink_smem_pipe *tx_pipe;
+       struct qcom_glink *glink;
+       struct device *dev;
+       u32 remote_pid;
+       __le32 *descs;
+       size_t size;
+       int ret;
+
+       dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+       if (!dev)
+               return ERR_PTR(-ENOMEM);
+
+       dev->parent = parent;
+       dev->of_node = node;
+       dev->release = qcom_glink_smem_release;
+       dev_set_name(dev, "%s:%s", node->parent->name, node->name);
+       ret = device_register(dev);
+       if (ret) {
+               pr_err("failed to register glink edge\n");
+               return ERR_PTR(ret);
+       }
+
+       ret = of_property_read_u32(dev->of_node, "qcom,remote-pid",
+                                  &remote_pid);
+       if (ret) {
+               dev_err(dev, "failed to parse qcom,remote-pid\n");
+               goto err_put_dev;
+       }
+
+       rx_pipe = devm_kzalloc(dev, sizeof(*rx_pipe), GFP_KERNEL);
+       tx_pipe = devm_kzalloc(dev, sizeof(*tx_pipe), GFP_KERNEL);
+       if (!rx_pipe || !tx_pipe) {
+               ret = -ENOMEM;
+               goto err_put_dev;
+       }
+
+       ret = qcom_smem_alloc(remote_pid,
+                             SMEM_GLINK_NATIVE_XPRT_DESCRIPTOR, 32);
+       if (ret && ret != -EEXIST) {
+               dev_err(dev, "failed to allocate glink descriptors\n");
+               goto err_put_dev;
+       }
+
+       descs = qcom_smem_get(remote_pid,
+                             SMEM_GLINK_NATIVE_XPRT_DESCRIPTOR, &size);
+       if (IS_ERR(descs)) {
+               dev_err(dev, "failed to acquire xprt descriptor\n");
+               ret = PTR_ERR(descs);
+               goto err_put_dev;
+       }
+
+       if (size != 32) {
+               dev_err(dev, "glink descriptor of invalid size\n");
+               ret = -EINVAL;
+               goto err_put_dev;
+       }
+
+       tx_pipe->tail = &descs[0];
+       tx_pipe->head = &descs[1];
+       rx_pipe->tail = &descs[2];
+       rx_pipe->head = &descs[3];
+
+       ret = qcom_smem_alloc(remote_pid, SMEM_GLINK_NATIVE_XPRT_FIFO_0,
+                             SZ_16K);
+       if (ret && ret != -EEXIST) {
+               dev_err(dev, "failed to allocate TX fifo\n");
+               goto err_put_dev;
+       }
+
+       tx_pipe->fifo = qcom_smem_get(remote_pid, SMEM_GLINK_NATIVE_XPRT_FIFO_0,
+                                     &tx_pipe->native.length);
+       if (IS_ERR(tx_pipe->fifo)) {
+               dev_err(dev, "failed to acquire TX fifo\n");
+               ret = PTR_ERR(tx_pipe->fifo);
+               goto err_put_dev;
+       }
+
+       rx_pipe->native.avail = glink_smem_rx_avail;
+       rx_pipe->native.peak = glink_smem_rx_peak;
+       rx_pipe->native.advance = glink_smem_rx_advance;
+       rx_pipe->remote_pid = remote_pid;
+
+       tx_pipe->native.avail = glink_smem_tx_avail;
+       tx_pipe->native.write = glink_smem_tx_write;
+       tx_pipe->remote_pid = remote_pid;
+
+       *rx_pipe->tail = 0;
+       *tx_pipe->head = 0;
+
+       glink = qcom_glink_native_probe(dev,
+                                       &rx_pipe->native, &tx_pipe->native);
+       if (IS_ERR(glink)) {
+               ret = PTR_ERR(glink);
+               goto err_put_dev;
+       }
+
+       return glink;
+
+err_put_dev:
+       put_device(dev);
+
+       return ERR_PTR(ret);
+}
+EXPORT_SYMBOL_GPL(qcom_glink_smem_register);
+
+void qcom_glink_smem_unregister(struct qcom_glink *glink)
+{
+       qcom_glink_native_remove(glink);
+       qcom_glink_native_unregister(glink);
+}
+EXPORT_SYMBOL_GPL(qcom_glink_smem_unregister);
+
+MODULE_AUTHOR("Bjorn Andersson <bjorn.andersson@linaro.org>");
+MODULE_DESCRIPTION("Qualcomm GLINK SMEM driver");
+MODULE_LICENSE("GPL v2");
diff --git a/include/linux/rpmsg/qcom_glink.h b/include/linux/rpmsg/qcom_glink.h
new file mode 100644 (file)
index 0000000..a622f02
--- /dev/null
@@ -0,0 +1,27 @@
+#ifndef _LINUX_RPMSG_QCOM_GLINK_H
+#define _LINUX_RPMSG_QCOM_GLINK_H
+
+#include <linux/device.h>
+
+struct qcom_glink;
+
+#if IS_ENABLED(CONFIG_RPMSG_QCOM_GLINK_SMEM)
+
+struct qcom_glink *qcom_glink_smem_register(struct device *parent,
+                                           struct device_node *node);
+void qcom_glink_smem_unregister(struct qcom_glink *glink);
+
+#else
+
+static inline struct qcom_glink *
+qcom_glink_smem_register(struct device *parent,
+                        struct device_node *node)
+{
+       return NULL;
+}
+
+static inline void qcom_glink_smem_unregister(struct qcom_glink *glink) {}
+
+#endif
+
+#endif