Initial commit: OpenHarmony-v4.0-ReleaseOpenHarmony-v4.0-Release

1 files changed, 409 insertions, 0 deletions

diff --git a/arch/mips/kernel/rtlx.c b/arch/mips/kernel/rtlx.c
new file mode 100644
index 000000000..18c509c59
--- /dev/null
+++ b/arch/mips/kernel/rtlx.c
@@ -0,0 +1,409 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2005 MIPS Technologies, Inc.  All rights reserved.
+ * Copyright (C) 2005, 06 Ralf Baechle (ralf@linux-mips.org)
+ * Copyright (C) 2013 Imagination Technologies Ltd.
+ */
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/syscalls.h>
+#include <linux/moduleloader.h>
+#include <linux/atomic.h>
+#include <linux/sched/signal.h>
+
+#include <asm/mipsmtregs.h>
+#include <asm/mips_mt.h>
+#include <asm/processor.h>
+#include <asm/rtlx.h>
+#include <asm/setup.h>
+#include <asm/vpe.h>
+
+static int sp_stopping;
+struct rtlx_info *rtlx;
+struct chan_waitqueues channel_wqs[RTLX_CHANNELS];
+struct vpe_notifications rtlx_notify;
+void (*aprp_hook)(void) = NULL;
+EXPORT_SYMBOL(aprp_hook);
+
+static void __used dump_rtlx(void)
+{
+        int i;
+
+        pr_info("id 0x%lx state %d\n", rtlx->id, rtlx->state);
+
+        for (i = 0; i < RTLX_CHANNELS; i++) {
+                struct rtlx_channel *chan = &rtlx->channel[i];
+
+                pr_info(" rt_state %d lx_state %d buffer_size %d\n",
+                        chan->rt_state, chan->lx_state, chan->buffer_size);
+
+                pr_info(" rt_read %d rt_write %d\n",
+                        chan->rt_read, chan->rt_write);
+
+                pr_info(" lx_read %d lx_write %d\n",
+                        chan->lx_read, chan->lx_write);
+
+                pr_info(" rt_buffer <%s>\n", chan->rt_buffer);
+                pr_info(" lx_buffer <%s>\n", chan->lx_buffer);
+        }
+}
+
+/* call when we have the address of the shared structure from the SP side. */
+static int rtlx_init(struct rtlx_info *rtlxi)
+{
+        if (rtlxi->id != RTLX_ID) {
+                pr_err("no valid RTLX id at 0x%p 0x%lx\n", rtlxi, rtlxi->id);
+                return -ENOEXEC;
+        }
+
+        rtlx = rtlxi;
+
+        return 0;
+}
+
+/* notifications */
+void rtlx_starting(int vpe)
+{
+        int i;
+        sp_stopping = 0;
+
+        /* force a reload of rtlx */
+        rtlx = NULL;
+
+        /* wake up any sleeping rtlx_open's */
+        for (i = 0; i < RTLX_CHANNELS; i++)
+                wake_up_interruptible(&channel_wqs[i].lx_queue);
+}
+
+void rtlx_stopping(int vpe)
+{
+        int i;
+
+        sp_stopping = 1;
+        for (i = 0; i < RTLX_CHANNELS; i++)
+                wake_up_interruptible(&channel_wqs[i].lx_queue);
+}
+
+
+int rtlx_open(int index, int can_sleep)
+{
+        struct rtlx_info **p;
+        struct rtlx_channel *chan;
+        enum rtlx_state state;
+        int ret = 0;
+
+        if (index >= RTLX_CHANNELS) {
+                pr_debug("rtlx_open index out of range\n");
+                return -ENOSYS;
+        }
+
+        if (atomic_inc_return(&channel_wqs[index].in_open) > 1) {
+                pr_debug("rtlx_open channel %d already opened\n", index);
+                ret = -EBUSY;
+                goto out_fail;
+        }
+
+        if (rtlx == NULL) {
+                p = vpe_get_shared(aprp_cpu_index());
+                if (p == NULL) {
+                        if (can_sleep) {
+                                ret = __wait_event_interruptible(
+                                        channel_wqs[index].lx_queue,
+                                        (p = vpe_get_shared(aprp_cpu_index())));
+                                if (ret)
+                                        goto out_fail;
+                        } else {
+                                pr_debug("No SP program loaded, and device opened with O_NONBLOCK\n");
+                                ret = -ENOSYS;
+                                goto out_fail;
+                        }
+                }
+
+                smp_rmb();
+                if (*p == NULL) {
+                        if (can_sleep) {
+                                DEFINE_WAIT(wait);
+
+                                for (;;) {
+                                        prepare_to_wait(
+                                                &channel_wqs[index].lx_queue,
+                                                &wait, TASK_INTERRUPTIBLE);
+                                        smp_rmb();
+                                        if (*p != NULL)
+                                                break;
+                                        if (!signal_pending(current)) {
+                                                schedule();
+                                                continue;
+                                        }
+                                        ret = -ERESTARTSYS;
+                                        goto out_fail;
+                                }
+                                finish_wait(&channel_wqs[index].lx_queue,
+                                            &wait);
+                        } else {
+                                pr_err(" *vpe_get_shared is NULL. Has an SP program been loaded?\n");
+                                ret = -ENOSYS;
+                                goto out_fail;
+                        }
+                }
+
+                if ((unsigned int)*p < KSEG0) {
+                        pr_warn("vpe_get_shared returned an invalid pointer maybe an error code %d\n",
+                                (int)*p);
+                        ret = -ENOSYS;
+                        goto out_fail;
+                }
+
+                ret = rtlx_init(*p);
+                if (ret < 0)
+                        goto out_ret;
+        }
+
+        chan = &rtlx->channel[index];
+
+        state = xchg(&chan->lx_state, RTLX_STATE_OPENED);
+        if (state == RTLX_STATE_OPENED) {
+                ret = -EBUSY;
+                goto out_fail;
+        }
+
+out_fail:
+        smp_mb();
+        atomic_dec(&channel_wqs[index].in_open);
+        smp_mb();
+
+out_ret:
+        return ret;
+}
+
+int rtlx_release(int index)
+{
+        if (rtlx == NULL) {
+                pr_err("rtlx_release() with null rtlx\n");
+                return 0;
+        }
+        rtlx->channel[index].lx_state = RTLX_STATE_UNUSED;
+        return 0;
+}
+
+unsigned int rtlx_read_poll(int index, int can_sleep)
+{
+        struct rtlx_channel *chan;
+
+        if (rtlx == NULL)
+                return 0;
+
+        chan = &rtlx->channel[index];
+
+        /* data available to read? */
+        if (chan->lx_read == chan->lx_write) {
+                if (can_sleep) {
+                        int ret = __wait_event_interruptible(
+                                channel_wqs[index].lx_queue,
+                                (chan->lx_read != chan->lx_write) ||
+                                sp_stopping);
+                        if (ret)
+                                return ret;
+
+                        if (sp_stopping)
+                                return 0;
+                } else
+                        return 0;
+        }
+
+        return (chan->lx_write + chan->buffer_size - chan->lx_read)
+               % chan->buffer_size;
+}
+
+static inline int write_spacefree(int read, int write, int size)
+{
+        if (read == write) {
+                /*
+                 * Never fill the buffer completely, so indexes are always
+                 * equal if empty and only empty, or !equal if data available
+                 */
+                return size - 1;
+        }
+
+        return ((read + size - write) % size) - 1;
+}
+
+unsigned int rtlx_write_poll(int index)
+{
+        struct rtlx_channel *chan = &rtlx->channel[index];
+
+        return write_spacefree(chan->rt_read, chan->rt_write,
+                                chan->buffer_size);
+}
+
+ssize_t rtlx_read(int index, void __user *buff, size_t count)
+{
+        size_t lx_write, fl = 0L;
+        struct rtlx_channel *lx;
+        unsigned long failed;
+
+        if (rtlx == NULL)
+                return -ENOSYS;
+
+        lx = &rtlx->channel[index];
+
+        mutex_lock(&channel_wqs[index].mutex);
+        smp_rmb();
+        lx_write = lx->lx_write;
+
+        /* find out how much in total */
+        count = min(count,
+                     (size_t)(lx_write + lx->buffer_size - lx->lx_read)
+                     % lx->buffer_size);
+
+        /* then how much from the read pointer onwards */
+        fl = min(count, (size_t)lx->buffer_size - lx->lx_read);
+
+        failed = copy_to_user(buff, lx->lx_buffer + lx->lx_read, fl);
+        if (failed)
+                goto out;
+
+        /* and if there is anything left at the beginning of the buffer */
+        if (count - fl)
+                failed = copy_to_user(buff + fl, lx->lx_buffer, count - fl);
+
+out:
+        count -= failed;
+
+        smp_wmb();
+        lx->lx_read = (lx->lx_read + count) % lx->buffer_size;
+        smp_wmb();
+        mutex_unlock(&channel_wqs[index].mutex);
+
+        return count;
+}
+
+ssize_t rtlx_write(int index, const void __user *buffer, size_t count)
+{
+        struct rtlx_channel *rt;
+        unsigned long failed;
+        size_t rt_read;
+        size_t fl;
+
+        if (rtlx == NULL)
+                return -ENOSYS;
+
+        rt = &rtlx->channel[index];
+
+        mutex_lock(&channel_wqs[index].mutex);
+        smp_rmb();
+        rt_read = rt->rt_read;
+
+        /* total number of bytes to copy */
+        count = min_t(size_t, count, write_spacefree(rt_read, rt->rt_write,
+                                                     rt->buffer_size));
+
+        /* first bit from write pointer to the end of the buffer, or count */
+        fl = min(count, (size_t) rt->buffer_size - rt->rt_write);
+
+        failed = copy_from_user(rt->rt_buffer + rt->rt_write, buffer, fl);
+        if (failed)
+                goto out;
+
+        /* if there's any left copy to the beginning of the buffer */
+        if (count - fl)
+                failed = copy_from_user(rt->rt_buffer, buffer + fl, count - fl);
+
+out:
+        count -= failed;
+
+        smp_wmb();
+        rt->rt_write = (rt->rt_write + count) % rt->buffer_size;
+        smp_wmb();
+        mutex_unlock(&channel_wqs[index].mutex);
+
+        _interrupt_sp();
+
+        return count;
+}
+
+
+static int file_open(struct inode *inode, struct file *filp)
+{
+        return rtlx_open(iminor(inode), (filp->f_flags & O_NONBLOCK) ? 0 : 1);
+}
+
+static int file_release(struct inode *inode, struct file *filp)
+{
+        return rtlx_release(iminor(inode));
+}
+
+static __poll_t file_poll(struct file *file, poll_table *wait)
+{
+        int minor = iminor(file_inode(file));
+        __poll_t mask = 0;
+
+        poll_wait(file, &channel_wqs[minor].rt_queue, wait);
+        poll_wait(file, &channel_wqs[minor].lx_queue, wait);
+
+        if (rtlx == NULL)
+                return 0;
+
+        /* data available to read? */
+        if (rtlx_read_poll(minor, 0))
+                mask |= EPOLLIN | EPOLLRDNORM;
+
+        /* space to write */
+        if (rtlx_write_poll(minor))
+                mask |= EPOLLOUT | EPOLLWRNORM;
+
+        return mask;
+}
+
+static ssize_t file_read(struct file *file, char __user *buffer, size_t count,
+                         loff_t *ppos)
+{
+        int minor = iminor(file_inode(file));
+
+        /* data available? */
+        if (!rtlx_read_poll(minor, (file->f_flags & O_NONBLOCK) ? 0 : 1))
+                return 0;       /* -EAGAIN makes 'cat' whine */
+
+        return rtlx_read(minor, buffer, count);
+}
+
+static ssize_t file_write(struct file *file, const char __user *buffer,
+                          size_t count, loff_t *ppos)
+{
+        int minor = iminor(file_inode(file));
+
+        /* any space left... */
+        if (!rtlx_write_poll(minor)) {
+                int ret;
+
+                if (file->f_flags & O_NONBLOCK)
+                        return -EAGAIN;
+
+                ret = __wait_event_interruptible(channel_wqs[minor].rt_queue,
+                                           rtlx_write_poll(minor));
+                if (ret)
+                        return ret;
+        }
+
+        return rtlx_write(minor, buffer, count);
+}
+
+const struct file_operations rtlx_fops = {
+        .owner =   THIS_MODULE,
+        .open =    file_open,
+        .release = file_release,
+        .write =   file_write,
+        .read =    file_read,
+        .poll =    file_poll,
+        .llseek =  noop_llseek,
+};
+
+module_init(rtlx_module_init);
+module_exit(rtlx_module_exit);
+
+MODULE_DESCRIPTION("MIPS RTLX");
+MODULE_AUTHOR("Elizabeth Oldham, MIPS Technologies, Inc.");
+MODULE_LICENSE("GPL");