// 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/of_irq.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/mailbox_client.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 qcom_glink_smem {
struct device dev;
int irq;
struct qcom_glink *glink;
struct mbox_client mbox_client;
struct mbox_chan *mbox_chan;
u32 remote_pid;
};
struct glink_smem_pipe {
struct qcom_glink_pipe native;
__le32 *tail;
__le32 *head;
void *fifo;
struct qcom_glink_smem *smem;
};
#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);
struct qcom_glink_smem *smem = pipe->smem;
size_t len;
void *fifo;
u32 head;
u32 tail;
if (!pipe->fifo) {
fifo = qcom_smem_get(smem->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_peek(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 glink_smem_tx_kick(struct qcom_glink_pipe *glink_pipe)
{
struct glink_smem_pipe *pipe = to_smem_pipe(glink_pipe);
struct qcom_glink_smem *smem = pipe->smem;
mbox_send_message(smem->mbox_chan, NULL);
mbox_client_txdone(smem->mbox_chan, 0);
}
static irqreturn_t qcom_glink_smem_intr(int irq, void *data)
{
struct qcom_glink_smem *smem = data;
qcom_glink_native_rx(smem->glink);
return IRQ_HANDLED;
}
static void qcom_glink_smem_release(struct device *dev)
{
struct qcom_glink_smem *smem = container_of(dev, struct qcom_glink_smem, dev);
kfree(smem);
}
struct qcom_glink_smem *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_smem *smem;
struct qcom_glink *glink;
struct device *dev;
u32 remote_pid;
__le32 *descs;
size_t size;
int ret;
smem = kzalloc(sizeof(*smem), GFP_KERNEL);
if (!smem)
return ERR_PTR(-ENOMEM);
dev = &smem->dev;
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;
}
smem->remote_pid = remote_pid;
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;
}
smem->irq = of_irq_get(smem->dev.of_node, 0);
ret = devm_request_irq(&smem->dev, smem->irq, qcom_glink_smem_intr,
IRQF_NO_SUSPEND | IRQF_NO_AUTOEN,
"glink-smem", smem);
if (ret) {
dev_err(&smem->dev, "failed to request IRQ\n");
goto err_put_dev;
}
smem->mbox_client.dev = &smem->dev;
smem->mbox_client.knows_txdone = true;
smem->mbox_chan = mbox_request_channel(&smem->mbox_client, 0);
if (IS_ERR(smem->mbox_chan)) {
ret = dev_err_probe(&smem->dev, PTR_ERR(smem->mbox_chan),
"failed to acquire IPC channel\n");
goto err_put_dev;
}
rx_pipe->smem = smem;
rx_pipe->native.avail = glink_smem_rx_avail;
rx_pipe->native.peek = glink_smem_rx_peek;
rx_pipe->native.advance = glink_smem_rx_advance;
tx_pipe->smem = smem;
tx_pipe->native.avail = glink_smem_tx_avail;
tx_pipe->native.write = glink_smem_tx_write;
tx_pipe->native.kick = glink_smem_tx_kick;
*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_free_mbox;
}
smem->glink = glink;
enable_irq(smem->irq);
return smem;
err_free_mbox:
mbox_free_channel(smem->mbox_chan);
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_smem *smem)
{
struct qcom_glink *glink = smem->glink;
disable_irq(smem->irq);
qcom_glink_native_remove(glink);
mbox_free_channel(smem->mbox_chan);
device_unregister(&smem->dev);
}
EXPORT_SYMBOL_GPL(qcom_glink_smem_unregister);
MODULE_AUTHOR("Bjorn Andersson <[email protected]>");
MODULE_DESCRIPTION("Qualcomm GLINK SMEM driver");
MODULE_LICENSE("GPL v2");
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