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Diffstat (limited to 'drivers/rpmsg/qcom_glink_smem.c')
-rw-r--r--drivers/rpmsg/qcom_glink_smem.c306
1 files changed, 306 insertions, 0 deletions
diff --git a/drivers/rpmsg/qcom_glink_smem.c b/drivers/rpmsg/qcom_glink_smem.c
new file mode 100644
index 000000000..579bc4443
--- /dev/null
+++ b/drivers/rpmsg/qcom_glink_smem.c
@@ -0,0 +1,306 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2016, Linaro Ltd
+ */
+
+#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/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, unsigned int offset, size_t count)
+{
+ struct glink_smem_pipe *pipe = to_smem_pipe(np);
+ size_t len;
+ u32 tail;
+
+ tail = le32_to_cpu(*pipe->tail);
+ tail += offset;
+ if (tail >= pipe->native.length)
+ tail -= pipe->native.length;
+
+ len = min_t(size_t, count, pipe->native.length - tail);
+ if (len)
+ memcpy_fromio(data, pipe->fifo + tail, len);
+
+ if (len != count)
+ memcpy_fromio(data + len, pipe->fifo, (count - len));
+}
+
+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;
+
+ /* Ensure ordering of fifo and head update */
+ wmb();
+
+ *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:%pOFn", dev_name(parent->parent), node);
+ ret = device_register(dev);
+ if (ret) {
+ pr_err("failed to register glink edge\n");
+ put_device(dev);
+ 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,
+ GLINK_FEATURE_INTENT_REUSE,
+ &rx_pipe->native, &tx_pipe->native,
+ false);
+ if (IS_ERR(glink)) {
+ ret = PTR_ERR(glink);
+ goto err_put_dev;
+ }
+
+ return glink;
+
+err_put_dev:
+ device_unregister(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");