mirror of https://gitee.com/openkylin/linux.git
568 lines
15 KiB
C
568 lines
15 KiB
C
/*
|
|
* Copyright (C) ST-Ericsson SA 2010
|
|
* Author: Stefan Nilsson <stefan.xk.nilsson@stericsson.com> for ST-Ericsson.
|
|
* Author: Martin Persson <martin.persson@stericsson.com> for ST-Ericsson.
|
|
* License terms: GNU General Public License (GPL), version 2.
|
|
*/
|
|
|
|
/*
|
|
* Mailbox nomenclature:
|
|
*
|
|
* APE MODEM
|
|
* mbox pairX
|
|
* ..........................
|
|
* . .
|
|
* . peer .
|
|
* . send ---- .
|
|
* . --> | | .
|
|
* . | | .
|
|
* . ---- .
|
|
* . .
|
|
* . local .
|
|
* . rec ---- .
|
|
* . | | <-- .
|
|
* . | | .
|
|
* . ---- .
|
|
* .........................
|
|
*/
|
|
|
|
#include <linux/init.h>
|
|
#include <linux/module.h>
|
|
#include <linux/device.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/spinlock.h>
|
|
#include <linux/errno.h>
|
|
#include <linux/io.h>
|
|
#include <linux/irq.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/debugfs.h>
|
|
#include <linux/seq_file.h>
|
|
#include <linux/completion.h>
|
|
#include <mach/mbox.h>
|
|
|
|
#define MBOX_NAME "mbox"
|
|
|
|
#define MBOX_FIFO_DATA 0x000
|
|
#define MBOX_FIFO_ADD 0x004
|
|
#define MBOX_FIFO_REMOVE 0x008
|
|
#define MBOX_FIFO_THRES_FREE 0x00C
|
|
#define MBOX_FIFO_THRES_OCCUP 0x010
|
|
#define MBOX_FIFO_STATUS 0x014
|
|
|
|
#define MBOX_DISABLE_IRQ 0x4
|
|
#define MBOX_ENABLE_IRQ 0x0
|
|
#define MBOX_LATCH 1
|
|
|
|
/* Global list of all mailboxes */
|
|
static struct list_head mboxs = LIST_HEAD_INIT(mboxs);
|
|
|
|
static struct mbox *get_mbox_with_id(u8 id)
|
|
{
|
|
u8 i;
|
|
struct list_head *pos = &mboxs;
|
|
for (i = 0; i <= id; i++)
|
|
pos = pos->next;
|
|
|
|
return (struct mbox *) list_entry(pos, struct mbox, list);
|
|
}
|
|
|
|
int mbox_send(struct mbox *mbox, u32 mbox_msg, bool block)
|
|
{
|
|
int res = 0;
|
|
|
|
spin_lock(&mbox->lock);
|
|
|
|
dev_dbg(&(mbox->pdev->dev),
|
|
"About to buffer 0x%X to mailbox 0x%X."
|
|
" ri = %d, wi = %d\n",
|
|
mbox_msg, (u32)mbox, mbox->read_index,
|
|
mbox->write_index);
|
|
|
|
/* Check if write buffer is full */
|
|
while (((mbox->write_index + 1) % MBOX_BUF_SIZE) == mbox->read_index) {
|
|
if (!block) {
|
|
dev_dbg(&(mbox->pdev->dev),
|
|
"Buffer full in non-blocking call! "
|
|
"Returning -ENOMEM!\n");
|
|
res = -ENOMEM;
|
|
goto exit;
|
|
}
|
|
spin_unlock(&mbox->lock);
|
|
dev_dbg(&(mbox->pdev->dev),
|
|
"Buffer full in blocking call! Sleeping...\n");
|
|
mbox->client_blocked = 1;
|
|
wait_for_completion(&mbox->buffer_available);
|
|
dev_dbg(&(mbox->pdev->dev),
|
|
"Blocking send was woken up! Trying again...\n");
|
|
spin_lock(&mbox->lock);
|
|
}
|
|
|
|
mbox->buffer[mbox->write_index] = mbox_msg;
|
|
mbox->write_index = (mbox->write_index + 1) % MBOX_BUF_SIZE;
|
|
|
|
/*
|
|
* Indicate that we want an IRQ as soon as there is a slot
|
|
* in the FIFO
|
|
*/
|
|
writel(MBOX_ENABLE_IRQ, mbox->virtbase_peer + MBOX_FIFO_THRES_FREE);
|
|
|
|
exit:
|
|
spin_unlock(&mbox->lock);
|
|
return res;
|
|
}
|
|
EXPORT_SYMBOL(mbox_send);
|
|
|
|
#if defined(CONFIG_DEBUG_FS)
|
|
/*
|
|
* Expected input: <value> <nbr sends>
|
|
* Example: "echo 0xdeadbeef 4 > mbox-node" sends 0xdeadbeef 4 times
|
|
*/
|
|
static ssize_t mbox_write_fifo(struct device *dev,
|
|
struct device_attribute *attr,
|
|
const char *buf,
|
|
size_t count)
|
|
{
|
|
unsigned long mbox_mess;
|
|
unsigned long nbr_sends;
|
|
unsigned long i;
|
|
char int_buf[16];
|
|
char *token;
|
|
char *val;
|
|
|
|
struct mbox *mbox = (struct mbox *) dev->platform_data;
|
|
|
|
strncpy((char *) &int_buf, buf, sizeof(int_buf));
|
|
token = (char *) &int_buf;
|
|
|
|
/* Parse message */
|
|
val = strsep(&token, " ");
|
|
if ((val == NULL) || (strict_strtoul(val, 16, &mbox_mess) != 0))
|
|
mbox_mess = 0xDEADBEEF;
|
|
|
|
val = strsep(&token, " ");
|
|
if ((val == NULL) || (strict_strtoul(val, 10, &nbr_sends) != 0))
|
|
nbr_sends = 1;
|
|
|
|
dev_dbg(dev, "Will write 0x%lX %ld times using data struct at 0x%X\n",
|
|
mbox_mess, nbr_sends, (u32) mbox);
|
|
|
|
for (i = 0; i < nbr_sends; i++)
|
|
mbox_send(mbox, mbox_mess, true);
|
|
|
|
return count;
|
|
}
|
|
|
|
static ssize_t mbox_read_fifo(struct device *dev,
|
|
struct device_attribute *attr,
|
|
char *buf)
|
|
{
|
|
int mbox_value;
|
|
struct mbox *mbox = (struct mbox *) dev->platform_data;
|
|
|
|
if ((readl(mbox->virtbase_local + MBOX_FIFO_STATUS) & 0x7) <= 0)
|
|
return sprintf(buf, "Mailbox is empty\n");
|
|
|
|
mbox_value = readl(mbox->virtbase_local + MBOX_FIFO_DATA);
|
|
writel(MBOX_LATCH, (mbox->virtbase_local + MBOX_FIFO_REMOVE));
|
|
|
|
return sprintf(buf, "0x%X\n", mbox_value);
|
|
}
|
|
|
|
static DEVICE_ATTR(fifo, S_IWUGO | S_IRUGO, mbox_read_fifo, mbox_write_fifo);
|
|
|
|
static int mbox_show(struct seq_file *s, void *data)
|
|
{
|
|
struct list_head *pos;
|
|
u8 mbox_index = 0;
|
|
|
|
list_for_each(pos, &mboxs) {
|
|
struct mbox *m =
|
|
(struct mbox *) list_entry(pos, struct mbox, list);
|
|
if (m == NULL) {
|
|
seq_printf(s,
|
|
"Unable to retrieve mailbox %d\n",
|
|
mbox_index);
|
|
continue;
|
|
}
|
|
|
|
spin_lock(&m->lock);
|
|
if ((m->virtbase_peer == NULL) || (m->virtbase_local == NULL)) {
|
|
seq_printf(s, "MAILBOX %d not setup or corrupt\n",
|
|
mbox_index);
|
|
spin_unlock(&m->lock);
|
|
continue;
|
|
}
|
|
|
|
seq_printf(s,
|
|
"===========================\n"
|
|
" MAILBOX %d\n"
|
|
" PEER MAILBOX DUMP\n"
|
|
"---------------------------\n"
|
|
"FIFO: 0x%X (%d)\n"
|
|
"Free Threshold: 0x%.2X (%d)\n"
|
|
"Occupied Threshold: 0x%.2X (%d)\n"
|
|
"Status: 0x%.2X (%d)\n"
|
|
" Free spaces (ot): %d (%d)\n"
|
|
" Occup spaces (ot): %d (%d)\n"
|
|
"===========================\n"
|
|
" LOCAL MAILBOX DUMP\n"
|
|
"---------------------------\n"
|
|
"FIFO: 0x%.X (%d)\n"
|
|
"Free Threshold: 0x%.2X (%d)\n"
|
|
"Occupied Threshold: 0x%.2X (%d)\n"
|
|
"Status: 0x%.2X (%d)\n"
|
|
" Free spaces (ot): %d (%d)\n"
|
|
" Occup spaces (ot): %d (%d)\n"
|
|
"===========================\n"
|
|
"write_index: %d\n"
|
|
"read_index : %d\n"
|
|
"===========================\n"
|
|
"\n",
|
|
mbox_index,
|
|
readl(m->virtbase_peer + MBOX_FIFO_DATA),
|
|
readl(m->virtbase_peer + MBOX_FIFO_DATA),
|
|
readl(m->virtbase_peer + MBOX_FIFO_THRES_FREE),
|
|
readl(m->virtbase_peer + MBOX_FIFO_THRES_FREE),
|
|
readl(m->virtbase_peer + MBOX_FIFO_THRES_OCCUP),
|
|
readl(m->virtbase_peer + MBOX_FIFO_THRES_OCCUP),
|
|
readl(m->virtbase_peer + MBOX_FIFO_STATUS),
|
|
readl(m->virtbase_peer + MBOX_FIFO_STATUS),
|
|
(readl(m->virtbase_peer + MBOX_FIFO_STATUS) >> 4) & 0x7,
|
|
(readl(m->virtbase_peer + MBOX_FIFO_STATUS) >> 7) & 0x1,
|
|
(readl(m->virtbase_peer + MBOX_FIFO_STATUS) >> 0) & 0x7,
|
|
(readl(m->virtbase_peer + MBOX_FIFO_STATUS) >> 3) & 0x1,
|
|
readl(m->virtbase_local + MBOX_FIFO_DATA),
|
|
readl(m->virtbase_local + MBOX_FIFO_DATA),
|
|
readl(m->virtbase_local + MBOX_FIFO_THRES_FREE),
|
|
readl(m->virtbase_local + MBOX_FIFO_THRES_FREE),
|
|
readl(m->virtbase_local + MBOX_FIFO_THRES_OCCUP),
|
|
readl(m->virtbase_local + MBOX_FIFO_THRES_OCCUP),
|
|
readl(m->virtbase_local + MBOX_FIFO_STATUS),
|
|
readl(m->virtbase_local + MBOX_FIFO_STATUS),
|
|
(readl(m->virtbase_local + MBOX_FIFO_STATUS) >> 4) & 0x7,
|
|
(readl(m->virtbase_local + MBOX_FIFO_STATUS) >> 7) & 0x1,
|
|
(readl(m->virtbase_local + MBOX_FIFO_STATUS) >> 0) & 0x7,
|
|
(readl(m->virtbase_local + MBOX_FIFO_STATUS) >> 3) & 0x1,
|
|
m->write_index, m->read_index);
|
|
mbox_index++;
|
|
spin_unlock(&m->lock);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int mbox_open(struct inode *inode, struct file *file)
|
|
{
|
|
return single_open(file, mbox_show, NULL);
|
|
}
|
|
|
|
static const struct file_operations mbox_operations = {
|
|
.owner = THIS_MODULE,
|
|
.open = mbox_open,
|
|
.read = seq_read,
|
|
.llseek = seq_lseek,
|
|
.release = single_release,
|
|
};
|
|
#endif
|
|
|
|
static irqreturn_t mbox_irq(int irq, void *arg)
|
|
{
|
|
u32 mbox_value;
|
|
int nbr_occup;
|
|
int nbr_free;
|
|
struct mbox *mbox = (struct mbox *) arg;
|
|
|
|
spin_lock(&mbox->lock);
|
|
|
|
dev_dbg(&(mbox->pdev->dev),
|
|
"mbox IRQ [%d] received. ri = %d, wi = %d\n",
|
|
irq, mbox->read_index, mbox->write_index);
|
|
|
|
/*
|
|
* Check if we have any outgoing messages, and if there is space for
|
|
* them in the FIFO.
|
|
*/
|
|
if (mbox->read_index != mbox->write_index) {
|
|
/*
|
|
* Check by reading FREE for LOCAL since that indicates
|
|
* OCCUP for PEER
|
|
*/
|
|
nbr_free = (readl(mbox->virtbase_local + MBOX_FIFO_STATUS)
|
|
>> 4) & 0x7;
|
|
dev_dbg(&(mbox->pdev->dev),
|
|
"Status indicates %d empty spaces in the FIFO!\n",
|
|
nbr_free);
|
|
|
|
while ((nbr_free > 0) &&
|
|
(mbox->read_index != mbox->write_index)) {
|
|
/* Write the message and latch it into the FIFO */
|
|
writel(mbox->buffer[mbox->read_index],
|
|
(mbox->virtbase_peer + MBOX_FIFO_DATA));
|
|
writel(MBOX_LATCH,
|
|
(mbox->virtbase_peer + MBOX_FIFO_ADD));
|
|
dev_dbg(&(mbox->pdev->dev),
|
|
"Wrote message 0x%X to addr 0x%X\n",
|
|
mbox->buffer[mbox->read_index],
|
|
(u32) (mbox->virtbase_peer + MBOX_FIFO_DATA));
|
|
|
|
nbr_free--;
|
|
mbox->read_index =
|
|
(mbox->read_index + 1) % MBOX_BUF_SIZE;
|
|
}
|
|
|
|
/*
|
|
* Check if we still want IRQ:s when there is free
|
|
* space to send
|
|
*/
|
|
if (mbox->read_index != mbox->write_index) {
|
|
dev_dbg(&(mbox->pdev->dev),
|
|
"Still have messages to send, but FIFO full. "
|
|
"Request IRQ again!\n");
|
|
writel(MBOX_ENABLE_IRQ,
|
|
mbox->virtbase_peer + MBOX_FIFO_THRES_FREE);
|
|
} else {
|
|
dev_dbg(&(mbox->pdev->dev),
|
|
"No more messages to send. "
|
|
"Do not request IRQ again!\n");
|
|
writel(MBOX_DISABLE_IRQ,
|
|
mbox->virtbase_peer + MBOX_FIFO_THRES_FREE);
|
|
}
|
|
|
|
/*
|
|
* Check if we can signal any blocked clients that it is OK to
|
|
* start buffering again
|
|
*/
|
|
if (mbox->client_blocked &&
|
|
(((mbox->write_index + 1) % MBOX_BUF_SIZE)
|
|
!= mbox->read_index)) {
|
|
dev_dbg(&(mbox->pdev->dev),
|
|
"Waking up blocked client\n");
|
|
complete(&mbox->buffer_available);
|
|
mbox->client_blocked = 0;
|
|
}
|
|
}
|
|
|
|
/* Check if we have any incoming messages */
|
|
nbr_occup = readl(mbox->virtbase_local + MBOX_FIFO_STATUS) & 0x7;
|
|
if (nbr_occup == 0)
|
|
goto exit;
|
|
|
|
if (mbox->cb == NULL) {
|
|
dev_dbg(&(mbox->pdev->dev), "No receive callback registered, "
|
|
"leaving %d incoming messages in fifo!\n", nbr_occup);
|
|
goto exit;
|
|
}
|
|
|
|
/* Read and acknowledge the message */
|
|
mbox_value = readl(mbox->virtbase_local + MBOX_FIFO_DATA);
|
|
writel(MBOX_LATCH, (mbox->virtbase_local + MBOX_FIFO_REMOVE));
|
|
|
|
/* Notify consumer of new mailbox message */
|
|
dev_dbg(&(mbox->pdev->dev), "Calling callback for message 0x%X!\n",
|
|
mbox_value);
|
|
mbox->cb(mbox_value, mbox->client_data);
|
|
|
|
exit:
|
|
dev_dbg(&(mbox->pdev->dev), "Exit mbox IRQ. ri = %d, wi = %d\n",
|
|
mbox->read_index, mbox->write_index);
|
|
spin_unlock(&mbox->lock);
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
/* Setup is executed once for each mbox pair */
|
|
struct mbox *mbox_setup(u8 mbox_id, mbox_recv_cb_t *mbox_cb, void *priv)
|
|
{
|
|
struct resource *resource;
|
|
int irq;
|
|
int res;
|
|
struct mbox *mbox;
|
|
|
|
mbox = get_mbox_with_id(mbox_id);
|
|
if (mbox == NULL) {
|
|
dev_err(&(mbox->pdev->dev), "Incorrect mailbox id: %d!\n",
|
|
mbox_id);
|
|
goto exit;
|
|
}
|
|
|
|
/*
|
|
* Check if mailbox has been allocated to someone else,
|
|
* otherwise allocate it
|
|
*/
|
|
if (mbox->allocated) {
|
|
dev_err(&(mbox->pdev->dev), "Mailbox number %d is busy!\n",
|
|
mbox_id);
|
|
mbox = NULL;
|
|
goto exit;
|
|
}
|
|
mbox->allocated = true;
|
|
|
|
dev_dbg(&(mbox->pdev->dev), "Initiating mailbox number %d: 0x%X...\n",
|
|
mbox_id, (u32)mbox);
|
|
|
|
mbox->client_data = priv;
|
|
mbox->cb = mbox_cb;
|
|
|
|
/* Get addr for peer mailbox and ioremap it */
|
|
resource = platform_get_resource_byname(mbox->pdev,
|
|
IORESOURCE_MEM,
|
|
"mbox_peer");
|
|
if (resource == NULL) {
|
|
dev_err(&(mbox->pdev->dev),
|
|
"Unable to retrieve mbox peer resource\n");
|
|
mbox = NULL;
|
|
goto exit;
|
|
}
|
|
dev_dbg(&(mbox->pdev->dev),
|
|
"Resource name: %s start: 0x%X, end: 0x%X\n",
|
|
resource->name, resource->start, resource->end);
|
|
mbox->virtbase_peer =
|
|
ioremap(resource->start, resource->end - resource->start);
|
|
if (!mbox->virtbase_peer) {
|
|
dev_err(&(mbox->pdev->dev), "Unable to ioremap peer mbox\n");
|
|
mbox = NULL;
|
|
goto exit;
|
|
}
|
|
dev_dbg(&(mbox->pdev->dev),
|
|
"ioremapped peer physical: (0x%X-0x%X) to virtual: 0x%X\n",
|
|
resource->start, resource->end, (u32) mbox->virtbase_peer);
|
|
|
|
/* Get addr for local mailbox and ioremap it */
|
|
resource = platform_get_resource_byname(mbox->pdev,
|
|
IORESOURCE_MEM,
|
|
"mbox_local");
|
|
if (resource == NULL) {
|
|
dev_err(&(mbox->pdev->dev),
|
|
"Unable to retrieve mbox local resource\n");
|
|
mbox = NULL;
|
|
goto exit;
|
|
}
|
|
dev_dbg(&(mbox->pdev->dev),
|
|
"Resource name: %s start: 0x%X, end: 0x%X\n",
|
|
resource->name, resource->start, resource->end);
|
|
mbox->virtbase_local =
|
|
ioremap(resource->start, resource->end - resource->start);
|
|
if (!mbox->virtbase_local) {
|
|
dev_err(&(mbox->pdev->dev), "Unable to ioremap local mbox\n");
|
|
mbox = NULL;
|
|
goto exit;
|
|
}
|
|
dev_dbg(&(mbox->pdev->dev),
|
|
"ioremapped local physical: (0x%X-0x%X) to virtual: 0x%X\n",
|
|
resource->start, resource->end, (u32) mbox->virtbase_peer);
|
|
|
|
init_completion(&mbox->buffer_available);
|
|
mbox->client_blocked = 0;
|
|
|
|
/* Get IRQ for mailbox and allocate it */
|
|
irq = platform_get_irq_byname(mbox->pdev, "mbox_irq");
|
|
if (irq < 0) {
|
|
dev_err(&(mbox->pdev->dev),
|
|
"Unable to retrieve mbox irq resource\n");
|
|
mbox = NULL;
|
|
goto exit;
|
|
}
|
|
|
|
dev_dbg(&(mbox->pdev->dev), "Allocating irq %d...\n", irq);
|
|
res = request_irq(irq, mbox_irq, 0, mbox->name, (void *) mbox);
|
|
if (res < 0) {
|
|
dev_err(&(mbox->pdev->dev),
|
|
"Unable to allocate mbox irq %d\n", irq);
|
|
mbox = NULL;
|
|
goto exit;
|
|
}
|
|
|
|
/* Set up mailbox to not launch IRQ on free space in mailbox */
|
|
writel(MBOX_DISABLE_IRQ, mbox->virtbase_peer + MBOX_FIFO_THRES_FREE);
|
|
|
|
/*
|
|
* Set up mailbox to launch IRQ on new message if we have
|
|
* a callback set. If not, do not raise IRQ, but keep message
|
|
* in FIFO for manual retrieval
|
|
*/
|
|
if (mbox_cb != NULL)
|
|
writel(MBOX_ENABLE_IRQ,
|
|
mbox->virtbase_local + MBOX_FIFO_THRES_OCCUP);
|
|
else
|
|
writel(MBOX_DISABLE_IRQ,
|
|
mbox->virtbase_local + MBOX_FIFO_THRES_OCCUP);
|
|
|
|
#if defined(CONFIG_DEBUG_FS)
|
|
res = device_create_file(&(mbox->pdev->dev), &dev_attr_fifo);
|
|
if (res != 0)
|
|
dev_warn(&(mbox->pdev->dev),
|
|
"Unable to create mbox sysfs entry");
|
|
|
|
(void) debugfs_create_file("mbox", S_IFREG | S_IRUGO, NULL,
|
|
NULL, &mbox_operations);
|
|
#endif
|
|
|
|
dev_info(&(mbox->pdev->dev),
|
|
"Mailbox driver with index %d initated!\n", mbox_id);
|
|
|
|
exit:
|
|
return mbox;
|
|
}
|
|
EXPORT_SYMBOL(mbox_setup);
|
|
|
|
|
|
int __init mbox_probe(struct platform_device *pdev)
|
|
{
|
|
struct mbox local_mbox;
|
|
struct mbox *mbox;
|
|
int res = 0;
|
|
dev_dbg(&(pdev->dev), "Probing mailbox (pdev = 0x%X)...\n", (u32) pdev);
|
|
|
|
memset(&local_mbox, 0x0, sizeof(struct mbox));
|
|
|
|
/* Associate our mbox data with the platform device */
|
|
res = platform_device_add_data(pdev,
|
|
(void *) &local_mbox,
|
|
sizeof(struct mbox));
|
|
if (res != 0) {
|
|
dev_err(&(pdev->dev),
|
|
"Unable to allocate driver platform data!\n");
|
|
goto exit;
|
|
}
|
|
|
|
mbox = (struct mbox *) pdev->dev.platform_data;
|
|
mbox->pdev = pdev;
|
|
mbox->write_index = 0;
|
|
mbox->read_index = 0;
|
|
|
|
INIT_LIST_HEAD(&(mbox->list));
|
|
list_add_tail(&(mbox->list), &mboxs);
|
|
|
|
sprintf(mbox->name, "%s", MBOX_NAME);
|
|
spin_lock_init(&mbox->lock);
|
|
|
|
dev_info(&(pdev->dev), "Mailbox driver loaded\n");
|
|
|
|
exit:
|
|
return res;
|
|
}
|
|
|
|
static struct platform_driver mbox_driver = {
|
|
.driver = {
|
|
.name = MBOX_NAME,
|
|
.owner = THIS_MODULE,
|
|
},
|
|
};
|
|
|
|
static int __init mbox_init(void)
|
|
{
|
|
return platform_driver_probe(&mbox_driver, mbox_probe);
|
|
}
|
|
|
|
module_init(mbox_init);
|
|
|
|
void __exit mbox_exit(void)
|
|
{
|
|
platform_driver_unregister(&mbox_driver);
|
|
}
|
|
|
|
module_exit(mbox_exit);
|
|
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_DESCRIPTION("MBOX driver");
|