From 52a49306d7d19ef127e6d6f4fd92f84d4864296f Mon Sep 17 00:00:00 2001 From: Andrew Bresticker Date: Thu, 30 Oct 2014 13:01:07 -0700 Subject: mailbox: Don't unnecessarily re-arm the polling timer poll_txdone() will unconditionally re-arm the polling timer if there was an active request, even if the active request completed and no other requests were submitted. This is fixed by: - only re-arming the timer if the controller reported that the current transmission has not completed, and, - moving the call to poll_txdone() into msg_submit() so that the controller gets polled (and the timer re-armed, if necessary) whenever a new message is submitted. Signed-off-by: Andrew Bresticker Reviewed-by: Thierry Reding Signed-off-by: Jassi Brar --- drivers/mailbox/mailbox.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/drivers/mailbox/mailbox.c b/drivers/mailbox/mailbox.c index afcb430508ec..c281e5562876 100644 --- a/drivers/mailbox/mailbox.c +++ b/drivers/mailbox/mailbox.c @@ -28,6 +28,8 @@ static LIST_HEAD(mbox_cons); static DEFINE_MUTEX(con_mutex); +static void poll_txdone(unsigned long data); + static int add_to_rbuf(struct mbox_chan *chan, void *mssg) { int idx; @@ -60,7 +62,7 @@ static void msg_submit(struct mbox_chan *chan) unsigned count, idx; unsigned long flags; void *data; - int err; + int err = -EBUSY; spin_lock_irqsave(&chan->lock, flags); @@ -84,6 +86,9 @@ static void msg_submit(struct mbox_chan *chan) } exit: spin_unlock_irqrestore(&chan->lock, flags); + + if (!err && chan->txdone_method == TXDONE_BY_POLL) + poll_txdone((unsigned long)chan->mbox); } static void tx_tick(struct mbox_chan *chan, int r) @@ -117,10 +122,11 @@ static void poll_txdone(unsigned long data) struct mbox_chan *chan = &mbox->chans[i]; if (chan->active_req && chan->cl) { - resched = true; txdone = chan->mbox->ops->last_tx_done(chan); if (txdone) tx_tick(chan, 0); + else + resched = true; } } @@ -252,9 +258,6 @@ int mbox_send_message(struct mbox_chan *chan, void *mssg) msg_submit(chan); - if (chan->txdone_method == TXDONE_BY_POLL) - poll_txdone((unsigned long)chan->mbox); - if (chan->cl->tx_block && chan->active_req) { unsigned long wait; int ret; -- cgit v1.2.3-59-g8ed1b From 97b0c7bd2e86c6e1e00c6b7178cf953d5f70c71a Mon Sep 17 00:00:00 2001 From: Sudeep Holla Date: Tue, 11 Nov 2014 18:33:01 +0000 Subject: mailbox: add tx_prepare client callback If the mailbox controller expects the payload is in place before initiating the transmit, then it's impossible to reuse the list maintained by core mailbox code currently. Maintaining another list for sending the message in the controller seems totally unnecessary as core mailbox library already provides that feature. This patch introduces tx_prepare callback in mbox_client which can be used by the core mailbox library before initiating the transaction through mbox->ops->send_data. The client driver can implement this callback to ensure the payload is copied to the shared memory. Signed-off-by: Sudeep Holla Cc: Arnd Bergmann Signed-off-by: Jassi Brar --- drivers/mailbox/mailbox.c | 2 ++ include/linux/mailbox_client.h | 3 +++ 2 files changed, 5 insertions(+) diff --git a/drivers/mailbox/mailbox.c b/drivers/mailbox/mailbox.c index c281e5562876..58789b027708 100644 --- a/drivers/mailbox/mailbox.c +++ b/drivers/mailbox/mailbox.c @@ -78,6 +78,8 @@ static void msg_submit(struct mbox_chan *chan) data = chan->msg_data[idx]; + if (chan->cl->tx_prepare) + chan->cl->tx_prepare(chan->cl, data); /* Try to submit a message to the MBOX controller */ err = chan->mbox->ops->send_data(chan, data); if (!err) { diff --git a/include/linux/mailbox_client.h b/include/linux/mailbox_client.h index 307d9cab2026..1726ccbd8009 100644 --- a/include/linux/mailbox_client.h +++ b/include/linux/mailbox_client.h @@ -25,6 +25,8 @@ struct mbox_chan; * if the client receives some ACK packet for transmission. * Unused if the controller already has TX_Done/RTR IRQ. * @rx_callback: Atomic callback to provide client the data received + * @tx_prepare: Atomic callback to ask client to prepare the payload + * before initiating the transmission if required. * @tx_done: Atomic callback to tell client of data transmission */ struct mbox_client { @@ -34,6 +36,7 @@ struct mbox_client { bool knows_txdone; void (*rx_callback)(struct mbox_client *cl, void *mssg); + void (*tx_prepare)(struct mbox_client *cl, void *mssg); void (*tx_done)(struct mbox_client *cl, void *mssg, int r); }; -- cgit v1.2.3-59-g8ed1b From 8841a66aaa7c3b1dfeeb4192d05f2ca86df58f00 Mon Sep 17 00:00:00 2001 From: Suman Anna Date: Mon, 3 Nov 2014 17:05:50 -0600 Subject: mailbox/omap: adapt to the new mailbox framework The OMAP mailbox driver and its existing clients (remoteproc for OMAP4+) are adapted to use the generic mailbox framework. The main changes for the adaptation are: - The tasklet used for Tx is replaced with the state machine from the generic mailbox framework. The workqueue used for processing the received messages stays intact for minimizing the effects on the OMAP mailbox clients. - The existing exported client API, omap_mbox_get, omap_mbox_put and omap_mbox_send_msg are deleted, as the framework provides equivalent functionality. A OMAP-specific omap_mbox_request_channel is added though to support non-DT way of requesting mailboxes. - The OMAP mailbox driver is integrated with the mailbox framework through the proper implementations of mbox_chan_ops, except for .last_tx_done and .peek_data. The OMAP mailbox driver does not need these ops, as it is completely interrupt driven. - The OMAP mailbox driver uses a custom of_xlate controller ops that allows phandles for the pargs specifier instead of indexing to avoid any channel registration order dependencies. - The new framework does not support multiple clients operating on a single channel, so the reference counting logic is simplified. - The remoteproc driver (current client) is adapted to use the new API. The notifier callbacks used within this client is replaced with the regular callbacks from the newer framework. - The exported OMAP mailbox API are limited to omap_mbox_save_ctx, omap_mbox_restore_ctx, omap_mbox_enable_irq & omap_mbox_disable_irq, with the signature modified to take in the new mbox_chan handle instead of the OMAP specific omap_mbox handle. The first 2 will be removed when the OMAP mailbox driver is adapted to runtime_pm. The other exported API omap_mbox_request_channel will be removed once existing legacy users are converted to DT. Signed-off-by: Suman Anna Cc: Ohad Ben-Cohen Signed-off-by: Jassi Brar --- .../devicetree/bindings/mailbox/omap-mailbox.txt | 23 ++ drivers/mailbox/omap-mailbox.c | 346 ++++++++++++--------- drivers/remoteproc/omap_remoteproc.c | 51 +-- include/linux/omap-mailbox.h | 16 +- 4 files changed, 256 insertions(+), 180 deletions(-) diff --git a/Documentation/devicetree/bindings/mailbox/omap-mailbox.txt b/Documentation/devicetree/bindings/mailbox/omap-mailbox.txt index 48edc4b92afb..d1a043339c11 100644 --- a/Documentation/devicetree/bindings/mailbox/omap-mailbox.txt +++ b/Documentation/devicetree/bindings/mailbox/omap-mailbox.txt @@ -43,6 +43,9 @@ Required properties: device. The format is dependent on which interrupt controller the OMAP device uses - ti,hwmods: Name of the hwmod associated with the mailbox +- #mbox-cells: Common mailbox binding property to identify the number + of cells required for the mailbox specifier. Should be + 1 - ti,mbox-num-users: Number of targets (processor devices) that the mailbox device can interrupt - ti,mbox-num-fifos: Number of h/w fifo queues within the mailbox IP block @@ -72,6 +75,18 @@ data that represent the following: Cell #3 (usr_id) - mailbox user id for identifying the interrupt line associated with generating a tx/rx fifo interrupt. +Mailbox Users: +============== +A device needing to communicate with a target processor device should specify +them using the common mailbox binding properties, "mboxes" and the optional +"mbox-names" (please see Documentation/devicetree/bindings/mailbox/mailbox.txt +for details). Each value of the mboxes property should contain a phandle to the +mailbox controller device node and an args specifier that will be the phandle to +the intended sub-mailbox child node to be used for communication. The equivalent +"mbox-names" property value can be used to give a name to the communication channel +to be used by the client user. + + Example: -------- @@ -81,6 +96,7 @@ mailbox: mailbox@4a0f4000 { reg = <0x4a0f4000 0x200>; interrupts = ; ti,hwmods = "mailbox"; + #mbox-cells = <1>; ti,mbox-num-users = <3>; ti,mbox-num-fifos = <8>; mbox_ipu: mbox_ipu { @@ -93,12 +109,19 @@ mailbox: mailbox@4a0f4000 { }; }; +dsp { + ... + mboxes = <&mailbox &mbox_dsp>; + ... +}; + /* AM33xx */ mailbox: mailbox@480C8000 { compatible = "ti,omap4-mailbox"; reg = <0x480C8000 0x200>; interrupts = <77>; ti,hwmods = "mailbox"; + #mbox-cells = <1>; ti,mbox-num-users = <4>; ti,mbox-num-fifos = <8>; mbox_wkupm3: wkup_m3 { diff --git a/drivers/mailbox/omap-mailbox.c b/drivers/mailbox/omap-mailbox.c index bcc7ee129276..66b83ca94dcf 100644 --- a/drivers/mailbox/omap-mailbox.c +++ b/drivers/mailbox/omap-mailbox.c @@ -29,13 +29,14 @@ #include #include #include -#include #include #include #include #include #include #include +#include +#include #define MAILBOX_REVISION 0x000 #define MAILBOX_MESSAGE(m) (0x040 + 4 * (m)) @@ -80,7 +81,6 @@ struct omap_mbox_queue { spinlock_t lock; struct kfifo fifo; struct work_struct work; - struct tasklet_struct tasklet; struct omap_mbox *mbox; bool full; }; @@ -92,6 +92,7 @@ struct omap_mbox_device { u32 num_users; u32 num_fifos; struct omap_mbox **mboxes; + struct mbox_controller controller; struct list_head elem; }; @@ -110,15 +111,14 @@ struct omap_mbox_fifo_info { struct omap_mbox { const char *name; int irq; - struct omap_mbox_queue *txq, *rxq; + struct omap_mbox_queue *rxq; struct device *dev; struct omap_mbox_device *parent; struct omap_mbox_fifo tx_fifo; struct omap_mbox_fifo rx_fifo; u32 ctx[OMAP4_MBOX_NR_REGS]; u32 intr_type; - int use_count; - struct blocking_notifier_head notifier; + struct mbox_chan *chan; }; /* global variables for the mailbox devices */ @@ -129,6 +129,14 @@ static unsigned int mbox_kfifo_size = CONFIG_OMAP_MBOX_KFIFO_SIZE; module_param(mbox_kfifo_size, uint, S_IRUGO); MODULE_PARM_DESC(mbox_kfifo_size, "Size of omap's mailbox kfifo (bytes)"); +static struct omap_mbox *mbox_chan_to_omap_mbox(struct mbox_chan *chan) +{ + if (!chan || !chan->con_priv) + return NULL; + + return (struct omap_mbox *)chan->con_priv; +} + static inline unsigned int mbox_read_reg(struct omap_mbox_device *mdev, size_t ofs) { @@ -194,41 +202,14 @@ static int is_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq) return (int)(enable & status & bit); } -/* - * message sender - */ -int omap_mbox_msg_send(struct omap_mbox *mbox, mbox_msg_t msg) -{ - struct omap_mbox_queue *mq = mbox->txq; - int ret = 0, len; - - spin_lock_bh(&mq->lock); - - if (kfifo_avail(&mq->fifo) < sizeof(msg)) { - ret = -ENOMEM; - goto out; - } - - if (kfifo_is_empty(&mq->fifo) && !mbox_fifo_full(mbox)) { - mbox_fifo_write(mbox, msg); - goto out; - } - - len = kfifo_in(&mq->fifo, (unsigned char *)&msg, sizeof(msg)); - WARN_ON(len != sizeof(msg)); - - tasklet_schedule(&mbox->txq->tasklet); - -out: - spin_unlock_bh(&mq->lock); - return ret; -} -EXPORT_SYMBOL(omap_mbox_msg_send); - -void omap_mbox_save_ctx(struct omap_mbox *mbox) +void omap_mbox_save_ctx(struct mbox_chan *chan) { int i; int nr_regs; + struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan); + + if (WARN_ON(!mbox)) + return; if (mbox->intr_type) nr_regs = OMAP4_MBOX_NR_REGS; @@ -243,10 +224,14 @@ void omap_mbox_save_ctx(struct omap_mbox *mbox) } EXPORT_SYMBOL(omap_mbox_save_ctx); -void omap_mbox_restore_ctx(struct omap_mbox *mbox) +void omap_mbox_restore_ctx(struct mbox_chan *chan) { int i; int nr_regs; + struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan); + + if (WARN_ON(!mbox)) + return; if (mbox->intr_type) nr_regs = OMAP4_MBOX_NR_REGS; @@ -254,14 +239,13 @@ void omap_mbox_restore_ctx(struct omap_mbox *mbox) nr_regs = MBOX_NR_REGS; for (i = 0; i < nr_regs; i++) { mbox_write_reg(mbox->parent, mbox->ctx[i], i * sizeof(u32)); - dev_dbg(mbox->dev, "%s: [%02x] %08x\n", __func__, i, mbox->ctx[i]); } } EXPORT_SYMBOL(omap_mbox_restore_ctx); -void omap_mbox_enable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq) +static void _omap_mbox_enable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq) { u32 l; struct omap_mbox_fifo *fifo = (irq == IRQ_TX) ? @@ -273,9 +257,8 @@ void omap_mbox_enable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq) l |= bit; mbox_write_reg(mbox->parent, l, irqenable); } -EXPORT_SYMBOL(omap_mbox_enable_irq); -void omap_mbox_disable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq) +static void _omap_mbox_disable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq) { struct omap_mbox_fifo *fifo = (irq == IRQ_TX) ? &mbox->tx_fifo : &mbox->rx_fifo; @@ -291,28 +274,28 @@ void omap_mbox_disable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq) mbox_write_reg(mbox->parent, bit, irqdisable); } -EXPORT_SYMBOL(omap_mbox_disable_irq); -static void mbox_tx_tasklet(unsigned long tx_data) +void omap_mbox_enable_irq(struct mbox_chan *chan, omap_mbox_irq_t irq) { - struct omap_mbox *mbox = (struct omap_mbox *)tx_data; - struct omap_mbox_queue *mq = mbox->txq; - mbox_msg_t msg; - int ret; + struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan); - while (kfifo_len(&mq->fifo)) { - if (mbox_fifo_full(mbox)) { - omap_mbox_enable_irq(mbox, IRQ_TX); - break; - } + if (WARN_ON(!mbox)) + return; - ret = kfifo_out(&mq->fifo, (unsigned char *)&msg, - sizeof(msg)); - WARN_ON(ret != sizeof(msg)); + _omap_mbox_enable_irq(mbox, irq); +} +EXPORT_SYMBOL(omap_mbox_enable_irq); - mbox_fifo_write(mbox, msg); - } +void omap_mbox_disable_irq(struct mbox_chan *chan, omap_mbox_irq_t irq) +{ + struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan); + + if (WARN_ON(!mbox)) + return; + + _omap_mbox_disable_irq(mbox, irq); } +EXPORT_SYMBOL(omap_mbox_disable_irq); /* * Message receiver(workqueue) @@ -328,12 +311,11 @@ static void mbox_rx_work(struct work_struct *work) len = kfifo_out(&mq->fifo, (unsigned char *)&msg, sizeof(msg)); WARN_ON(len != sizeof(msg)); - blocking_notifier_call_chain(&mq->mbox->notifier, len, - (void *)msg); + mbox_chan_received_data(mq->mbox->chan, (void *)msg); spin_lock_irq(&mq->lock); if (mq->full) { mq->full = false; - omap_mbox_enable_irq(mq->mbox, IRQ_RX); + _omap_mbox_enable_irq(mq->mbox, IRQ_RX); } spin_unlock_irq(&mq->lock); } @@ -344,9 +326,9 @@ static void mbox_rx_work(struct work_struct *work) */ static void __mbox_tx_interrupt(struct omap_mbox *mbox) { - omap_mbox_disable_irq(mbox, IRQ_TX); + _omap_mbox_disable_irq(mbox, IRQ_TX); ack_mbox_irq(mbox, IRQ_TX); - tasklet_schedule(&mbox->txq->tasklet); + mbox_chan_txdone(mbox->chan, 0); } static void __mbox_rx_interrupt(struct omap_mbox *mbox) @@ -357,7 +339,7 @@ static void __mbox_rx_interrupt(struct omap_mbox *mbox) while (!mbox_fifo_empty(mbox)) { if (unlikely(kfifo_avail(&mq->fifo) < sizeof(msg))) { - omap_mbox_disable_irq(mbox, IRQ_RX); + _omap_mbox_disable_irq(mbox, IRQ_RX); mq->full = true; goto nomem; } @@ -388,11 +370,13 @@ static irqreturn_t mbox_interrupt(int irq, void *p) } static struct omap_mbox_queue *mbox_queue_alloc(struct omap_mbox *mbox, - void (*work) (struct work_struct *), - void (*tasklet)(unsigned long)) + void (*work)(struct work_struct *)) { struct omap_mbox_queue *mq; + if (!work) + return NULL; + mq = kzalloc(sizeof(struct omap_mbox_queue), GFP_KERNEL); if (!mq) return NULL; @@ -402,12 +386,9 @@ static struct omap_mbox_queue *mbox_queue_alloc(struct omap_mbox *mbox, if (kfifo_alloc(&mq->fifo, mbox_kfifo_size, GFP_KERNEL)) goto error; - if (work) - INIT_WORK(&mq->work, work); - - if (tasklet) - tasklet_init(&mq->tasklet, tasklet, (unsigned long)mbox); + INIT_WORK(&mq->work, work); return mq; + error: kfree(mq); return NULL; @@ -423,71 +404,35 @@ static int omap_mbox_startup(struct omap_mbox *mbox) { int ret = 0; struct omap_mbox_queue *mq; - struct omap_mbox_device *mdev = mbox->parent; - mutex_lock(&mdev->cfg_lock); - ret = pm_runtime_get_sync(mdev->dev); - if (unlikely(ret < 0)) - goto fail_startup; - - if (!mbox->use_count++) { - mq = mbox_queue_alloc(mbox, NULL, mbox_tx_tasklet); - if (!mq) { - ret = -ENOMEM; - goto fail_alloc_txq; - } - mbox->txq = mq; + mq = mbox_queue_alloc(mbox, mbox_rx_work); + if (!mq) + return -ENOMEM; + mbox->rxq = mq; + mq->mbox = mbox; + + ret = request_irq(mbox->irq, mbox_interrupt, IRQF_SHARED, + mbox->name, mbox); + if (unlikely(ret)) { + pr_err("failed to register mailbox interrupt:%d\n", ret); + goto fail_request_irq; + } - mq = mbox_queue_alloc(mbox, mbox_rx_work, NULL); - if (!mq) { - ret = -ENOMEM; - goto fail_alloc_rxq; - } - mbox->rxq = mq; - mq->mbox = mbox; - ret = request_irq(mbox->irq, mbox_interrupt, IRQF_SHARED, - mbox->name, mbox); - if (unlikely(ret)) { - pr_err("failed to register mailbox interrupt:%d\n", - ret); - goto fail_request_irq; - } + _omap_mbox_enable_irq(mbox, IRQ_RX); - omap_mbox_enable_irq(mbox, IRQ_RX); - } - mutex_unlock(&mdev->cfg_lock); return 0; fail_request_irq: mbox_queue_free(mbox->rxq); -fail_alloc_rxq: - mbox_queue_free(mbox->txq); -fail_alloc_txq: - pm_runtime_put_sync(mdev->dev); - mbox->use_count--; -fail_startup: - mutex_unlock(&mdev->cfg_lock); return ret; } static void omap_mbox_fini(struct omap_mbox *mbox) { - struct omap_mbox_device *mdev = mbox->parent; - - mutex_lock(&mdev->cfg_lock); - - if (!--mbox->use_count) { - omap_mbox_disable_irq(mbox, IRQ_RX); - free_irq(mbox->irq, mbox); - tasklet_kill(&mbox->txq->tasklet); - flush_work(&mbox->rxq->work); - mbox_queue_free(mbox->txq); - mbox_queue_free(mbox->rxq); - } - - pm_runtime_put_sync(mdev->dev); - - mutex_unlock(&mdev->cfg_lock); + _omap_mbox_disable_irq(mbox, IRQ_RX); + free_irq(mbox->irq, mbox); + flush_work(&mbox->rxq->work); + mbox_queue_free(mbox->rxq); } static struct omap_mbox *omap_mbox_device_find(struct omap_mbox_device *mdev, @@ -509,42 +454,55 @@ static struct omap_mbox *omap_mbox_device_find(struct omap_mbox_device *mdev, return mbox; } -struct omap_mbox *omap_mbox_get(const char *name, struct notifier_block *nb) +struct mbox_chan *omap_mbox_request_channel(struct mbox_client *cl, + const char *chan_name) { + struct device *dev = cl->dev; struct omap_mbox *mbox = NULL; struct omap_mbox_device *mdev; + struct mbox_chan *chan; + unsigned long flags; int ret; + if (!dev) + return ERR_PTR(-ENODEV); + + if (dev->of_node) { + pr_err("%s: please use mbox_request_channel(), this API is supported only for OMAP non-DT usage\n", + __func__); + return ERR_PTR(-ENODEV); + } + mutex_lock(&omap_mbox_devices_lock); list_for_each_entry(mdev, &omap_mbox_devices, elem) { - mbox = omap_mbox_device_find(mdev, name); + mbox = omap_mbox_device_find(mdev, chan_name); if (mbox) break; } mutex_unlock(&omap_mbox_devices_lock); - if (!mbox) + if (!mbox || !mbox->chan) return ERR_PTR(-ENOENT); - if (nb) - blocking_notifier_chain_register(&mbox->notifier, nb); + chan = mbox->chan; + spin_lock_irqsave(&chan->lock, flags); + chan->msg_free = 0; + chan->msg_count = 0; + chan->active_req = NULL; + chan->cl = cl; + init_completion(&chan->tx_complete); + spin_unlock_irqrestore(&chan->lock, flags); - ret = omap_mbox_startup(mbox); + ret = chan->mbox->ops->startup(chan); if (ret) { - blocking_notifier_chain_unregister(&mbox->notifier, nb); - return ERR_PTR(-ENODEV); + pr_err("Unable to startup the chan (%d)\n", ret); + mbox_free_channel(chan); + chan = ERR_PTR(ret); } - return mbox; -} -EXPORT_SYMBOL(omap_mbox_get); - -void omap_mbox_put(struct omap_mbox *mbox, struct notifier_block *nb) -{ - blocking_notifier_chain_unregister(&mbox->notifier, nb); - omap_mbox_fini(mbox); + return chan; } -EXPORT_SYMBOL(omap_mbox_put); +EXPORT_SYMBOL(omap_mbox_request_channel); static struct class omap_mbox_class = { .name = "mbox", }; @@ -560,25 +518,25 @@ static int omap_mbox_register(struct omap_mbox_device *mdev) mboxes = mdev->mboxes; for (i = 0; mboxes[i]; i++) { struct omap_mbox *mbox = mboxes[i]; - mbox->dev = device_create(&omap_mbox_class, - mdev->dev, 0, mbox, "%s", mbox->name); + mbox->dev = device_create(&omap_mbox_class, mdev->dev, + 0, mbox, "%s", mbox->name); if (IS_ERR(mbox->dev)) { ret = PTR_ERR(mbox->dev); goto err_out; } - - BLOCKING_INIT_NOTIFIER_HEAD(&mbox->notifier); } mutex_lock(&omap_mbox_devices_lock); list_add(&mdev->elem, &omap_mbox_devices); mutex_unlock(&omap_mbox_devices_lock); - return 0; + ret = mbox_controller_register(&mdev->controller); err_out: - while (i--) - device_unregister(mboxes[i]->dev); + if (ret) { + while (i--) + device_unregister(mboxes[i]->dev); + } return ret; } @@ -594,12 +552,64 @@ static int omap_mbox_unregister(struct omap_mbox_device *mdev) list_del(&mdev->elem); mutex_unlock(&omap_mbox_devices_lock); + mbox_controller_unregister(&mdev->controller); + mboxes = mdev->mboxes; for (i = 0; mboxes[i]; i++) device_unregister(mboxes[i]->dev); return 0; } +static int omap_mbox_chan_startup(struct mbox_chan *chan) +{ + struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan); + struct omap_mbox_device *mdev = mbox->parent; + int ret = 0; + + mutex_lock(&mdev->cfg_lock); + pm_runtime_get_sync(mdev->dev); + ret = omap_mbox_startup(mbox); + if (ret) + pm_runtime_put_sync(mdev->dev); + mutex_unlock(&mdev->cfg_lock); + return ret; +} + +static void omap_mbox_chan_shutdown(struct mbox_chan *chan) +{ + struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan); + struct omap_mbox_device *mdev = mbox->parent; + + mutex_lock(&mdev->cfg_lock); + omap_mbox_fini(mbox); + pm_runtime_put_sync(mdev->dev); + mutex_unlock(&mdev->cfg_lock); +} + +static int omap_mbox_chan_send_data(struct mbox_chan *chan, void *data) +{ + struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan); + int ret = -EBUSY; + + if (!mbox) + return -EINVAL; + + if (!mbox_fifo_full(mbox)) { + mbox_fifo_write(mbox, (mbox_msg_t)data); + ret = 0; + } + + /* always enable the interrupt */ + _omap_mbox_enable_irq(mbox, IRQ_TX); + return ret; +} + +static struct mbox_chan_ops omap_mbox_chan_ops = { + .startup = omap_mbox_chan_startup, + .send_data = omap_mbox_chan_send_data, + .shutdown = omap_mbox_chan_shutdown, +}; + static const struct of_device_id omap_mailbox_of_match[] = { { .compatible = "ti,omap2-mailbox", @@ -619,10 +629,35 @@ static const struct of_device_id omap_mailbox_of_match[] = { }; MODULE_DEVICE_TABLE(of, omap_mailbox_of_match); +static struct mbox_chan *omap_mbox_of_xlate(struct mbox_controller *controller, + const struct of_phandle_args *sp) +{ + phandle phandle = sp->args[0]; + struct device_node *node; + struct omap_mbox_device *mdev; + struct omap_mbox *mbox; + + mdev = container_of(controller, struct omap_mbox_device, controller); + if (WARN_ON(!mdev)) + return NULL; + + node = of_find_node_by_phandle(phandle); + if (!node) { + pr_err("%s: could not find node phandle 0x%x\n", + __func__, phandle); + return NULL; + } + + mbox = omap_mbox_device_find(mdev, node->name); + of_node_put(node); + return mbox ? mbox->chan : NULL; +} + static int omap_mbox_probe(struct platform_device *pdev) { struct resource *mem; int ret; + struct mbox_chan *chnls; struct omap_mbox **list, *mbox, *mboxblk; struct omap_mbox_pdata *pdata = pdev->dev.platform_data; struct omap_mbox_dev_info *info = NULL; @@ -727,6 +762,11 @@ static int omap_mbox_probe(struct platform_device *pdev) if (!list) return -ENOMEM; + chnls = devm_kzalloc(&pdev->dev, (info_count + 1) * sizeof(*chnls), + GFP_KERNEL); + if (!chnls) + return -ENOMEM; + mboxblk = devm_kzalloc(&pdev->dev, info_count * sizeof(*mbox), GFP_KERNEL); if (!mboxblk) @@ -758,6 +798,8 @@ static int omap_mbox_probe(struct platform_device *pdev) mbox->irq = platform_get_irq(pdev, finfo->tx_irq); if (mbox->irq < 0) return mbox->irq; + mbox->chan = &chnls[i]; + chnls[i].con_priv = mbox; list[i] = mbox++; } @@ -766,6 +808,14 @@ static int omap_mbox_probe(struct platform_device *pdev) mdev->num_users = num_users; mdev->num_fifos = num_fifos; mdev->mboxes = list; + + /* OMAP does not have a Tx-Done IRQ, but rather a Tx-Ready IRQ */ + mdev->controller.txdone_irq = true; + mdev->controller.dev = mdev->dev; + mdev->controller.ops = &omap_mbox_chan_ops; + mdev->controller.chans = chnls; + mdev->controller.num_chans = info_count; + mdev->controller.of_xlate = omap_mbox_of_xlate; ret = omap_mbox_register(mdev); if (ret) return ret; diff --git a/drivers/remoteproc/omap_remoteproc.c b/drivers/remoteproc/omap_remoteproc.c index 51689721ea7a..cf92f6e7c5dc 100644 --- a/drivers/remoteproc/omap_remoteproc.c +++ b/drivers/remoteproc/omap_remoteproc.c @@ -27,6 +27,7 @@ #include #include #include +#include #include #include @@ -36,20 +37,19 @@ /** * struct omap_rproc - omap remote processor state - * @mbox: omap mailbox handle - * @nb: notifier block that will be invoked on inbound mailbox messages + * @mbox: mailbox channel handle + * @client: mailbox client to request the mailbox channel * @rproc: rproc handle */ struct omap_rproc { - struct omap_mbox *mbox; - struct notifier_block nb; + struct mbox_chan *mbox; + struct mbox_client client; struct rproc *rproc; }; /** * omap_rproc_mbox_callback() - inbound mailbox message handler - * @this: notifier block - * @index: unused + * @client: mailbox client pointer used for requesting the mailbox channel * @data: mailbox payload * * This handler is invoked by omap's mailbox driver whenever a mailbox @@ -61,13 +61,13 @@ struct omap_rproc { * that indicates different events. Those values are deliberately very * big so they don't coincide with virtqueue indices. */ -static int omap_rproc_mbox_callback(struct notifier_block *this, - unsigned long index, void *data) +static void omap_rproc_mbox_callback(struct mbox_client *client, void *data) { - mbox_msg_t msg = (mbox_msg_t) data; - struct omap_rproc *oproc = container_of(this, struct omap_rproc, nb); + struct omap_rproc *oproc = container_of(client, struct omap_rproc, + client); struct device *dev = oproc->rproc->dev.parent; const char *name = oproc->rproc->name; + u32 msg = (u32)data; dev_dbg(dev, "mbox msg: 0x%x\n", msg); @@ -84,8 +84,6 @@ static int omap_rproc_mbox_callback(struct notifier_block *this, if (rproc_vq_interrupt(oproc->rproc, msg) == IRQ_NONE) dev_dbg(dev, "no message was found in vqid %d\n", msg); } - - return NOTIFY_DONE; } /* kick a virtqueue */ @@ -96,8 +94,8 @@ static void omap_rproc_kick(struct rproc *rproc, int vqid) int ret; /* send the index of the triggered virtqueue in the mailbox payload */ - ret = omap_mbox_msg_send(oproc->mbox, vqid); - if (ret) + ret = mbox_send_message(oproc->mbox, (void *)vqid); + if (ret < 0) dev_err(dev, "omap_mbox_msg_send failed: %d\n", ret); } @@ -115,17 +113,22 @@ static int omap_rproc_start(struct rproc *rproc) struct platform_device *pdev = to_platform_device(dev); struct omap_rproc_pdata *pdata = pdev->dev.platform_data; int ret; + struct mbox_client *client = &oproc->client; if (pdata->set_bootaddr) pdata->set_bootaddr(rproc->bootaddr); - oproc->nb.notifier_call = omap_rproc_mbox_callback; + client->dev = dev; + client->tx_done = NULL; + client->rx_callback = omap_rproc_mbox_callback; + client->tx_block = false; + client->knows_txdone = false; - /* every omap rproc is assigned a mailbox instance for messaging */ - oproc->mbox = omap_mbox_get(pdata->mbox_name, &oproc->nb); + oproc->mbox = omap_mbox_request_channel(client, pdata->mbox_name); if (IS_ERR(oproc->mbox)) { - ret = PTR_ERR(oproc->mbox); - dev_err(dev, "omap_mbox_get failed: %d\n", ret); + ret = -EBUSY; + dev_err(dev, "mbox_request_channel failed: %ld\n", + PTR_ERR(oproc->mbox)); return ret; } @@ -136,9 +139,9 @@ static int omap_rproc_start(struct rproc *rproc) * Note that the reply will _not_ arrive immediately: this message * will wait in the mailbox fifo until the remote processor is booted. */ - ret = omap_mbox_msg_send(oproc->mbox, RP_MBOX_ECHO_REQUEST); - if (ret) { - dev_err(dev, "omap_mbox_get failed: %d\n", ret); + ret = mbox_send_message(oproc->mbox, (void *)RP_MBOX_ECHO_REQUEST); + if (ret < 0) { + dev_err(dev, "mbox_send_message failed: %d\n", ret); goto put_mbox; } @@ -151,7 +154,7 @@ static int omap_rproc_start(struct rproc *rproc) return 0; put_mbox: - omap_mbox_put(oproc->mbox, &oproc->nb); + mbox_free_channel(oproc->mbox); return ret; } @@ -168,7 +171,7 @@ static int omap_rproc_stop(struct rproc *rproc) if (ret) return ret; - omap_mbox_put(oproc->mbox, &oproc->nb); + mbox_free_channel(oproc->mbox); return 0; } diff --git a/include/linux/omap-mailbox.h b/include/linux/omap-mailbox.h index f8322d9cd235..587bbdd31f5a 100644 --- a/include/linux/omap-mailbox.h +++ b/include/linux/omap-mailbox.h @@ -10,20 +10,20 @@ #define OMAP_MAILBOX_H typedef u32 mbox_msg_t; -struct omap_mbox; typedef int __bitwise omap_mbox_irq_t; #define IRQ_TX ((__force omap_mbox_irq_t) 1) #define IRQ_RX ((__force omap_mbox_irq_t) 2) -int omap_mbox_msg_send(struct omap_mbox *, mbox_msg_t msg); +struct mbox_chan; +struct mbox_client; -struct omap_mbox *omap_mbox_get(const char *, struct notifier_block *nb); -void omap_mbox_put(struct omap_mbox *mbox, struct notifier_block *nb); +struct mbox_chan *omap_mbox_request_channel(struct mbox_client *cl, + const char *chan_name); -void omap_mbox_save_ctx(struct omap_mbox *mbox); -void omap_mbox_restore_ctx(struct omap_mbox *mbox); -void omap_mbox_enable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq); -void omap_mbox_disable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq); +void omap_mbox_save_ctx(struct mbox_chan *chan); +void omap_mbox_restore_ctx(struct mbox_chan *chan); +void omap_mbox_enable_irq(struct mbox_chan *chan, omap_mbox_irq_t irq); +void omap_mbox_disable_irq(struct mbox_chan *chan, omap_mbox_irq_t irq); #endif /* OMAP_MAILBOX_H */ -- cgit v1.2.3-59-g8ed1b From 86c22f8c9a3b71d42d38bfcd80372de72f573713 Mon Sep 17 00:00:00 2001 From: Ashwin Chaugule Date: Wed, 12 Nov 2014 19:59:38 -0500 Subject: Mailbox: Add support for Platform Communication Channel ACPI 5.0+ spec defines a generic mode of communication between the OS and a platform such as the BMC. This medium (PCC) is typically used by CPPC (ACPI CPU Performance management), RAS (ACPI reliability protocol) and MPST (ACPI Memory power states). This patch adds PCC support as a Mailbox Controller. As of ACPI v5.1 there is no provision for clients to lookup mailbox controllers in a way that Linux expects. e.g. in DT the clients can list the mailboxes they can associate with in the DT binding and then provide a unique index to lookup a channel within a mailbox. Since the ACPI spec doesn't have anything similar, we introduce a mailbox controller specific API so that when the client calls it, we know to lookup in the context of a specific controller. This also helps in keeping a consistent interface across DT and ACPI for such drivers. This patch implements basic PCC support using the ACPI v5.1 structures. IRQ mode support will be provided as follow up patches. Signed-off-by: Ashwin Chaugule Reviewed-by: Mark Brown Reviewed-by: Arnd Bergmann Signed-off-by: Jassi Brar --- drivers/mailbox/Kconfig | 12 ++ drivers/mailbox/Makefile | 2 + drivers/mailbox/mailbox.c | 4 +- drivers/mailbox/mailbox.h | 14 ++ drivers/mailbox/pcc.c | 403 ++++++++++++++++++++++++++++++++++++++++++++++ 5 files changed, 432 insertions(+), 3 deletions(-) create mode 100644 drivers/mailbox/mailbox.h create mode 100644 drivers/mailbox/pcc.c diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig index 9fd9c6717e0c..c04fed9eb15d 100644 --- a/drivers/mailbox/Kconfig +++ b/drivers/mailbox/Kconfig @@ -33,4 +33,16 @@ config OMAP_MBOX_KFIFO_SIZE Specify the default size of mailbox's kfifo buffers (bytes). This can also be changed at runtime (via the mbox_kfifo_size module parameter). + +config PCC + bool "Platform Communication Channel Driver" + depends on ACPI + help + ACPI 5.0+ spec defines a generic mode of communication + between the OS and a platform such as the BMC. This medium + (PCC) is typically used by CPPC (ACPI CPU Performance management), + RAS (ACPI reliability protocol) and MPST (ACPI Memory power + states). Select this driver if your platform implements the + PCC clients mentioned above. + endif diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile index 94ed7cefb14d..dd412c22208b 100644 --- a/drivers/mailbox/Makefile +++ b/drivers/mailbox/Makefile @@ -5,3 +5,5 @@ obj-$(CONFIG_MAILBOX) += mailbox.o obj-$(CONFIG_PL320_MBOX) += pl320-ipc.o obj-$(CONFIG_OMAP2PLUS_MBOX) += omap-mailbox.o + +obj-$(CONFIG_PCC) += pcc.o diff --git a/drivers/mailbox/mailbox.c b/drivers/mailbox/mailbox.c index 58789b027708..59aad4d5da53 100644 --- a/drivers/mailbox/mailbox.c +++ b/drivers/mailbox/mailbox.c @@ -21,9 +21,7 @@ #include #include -#define TXDONE_BY_IRQ BIT(0) /* controller has remote RTR irq */ -#define TXDONE_BY_POLL BIT(1) /* controller can read status of last TX */ -#define TXDONE_BY_ACK BIT(2) /* S/W ACK recevied by Client ticks the TX */ +#include "mailbox.h" static LIST_HEAD(mbox_cons); static DEFINE_MUTEX(con_mutex); diff --git a/drivers/mailbox/mailbox.h b/drivers/mailbox/mailbox.h new file mode 100644 index 000000000000..456ba68513bb --- /dev/null +++ b/drivers/mailbox/mailbox.h @@ -0,0 +1,14 @@ +/* + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#ifndef __MAILBOX_H +#define __MAILBOX_H + +#define TXDONE_BY_IRQ BIT(0) /* controller has remote RTR irq */ +#define TXDONE_BY_POLL BIT(1) /* controller can read status of last TX */ +#define TXDONE_BY_ACK BIT(2) /* S/W ACK recevied by Client ticks the TX */ + +#endif /* __MAILBOX_H */ diff --git a/drivers/mailbox/pcc.c b/drivers/mailbox/pcc.c new file mode 100644 index 000000000000..6dbf6fcbdfaf --- /dev/null +++ b/drivers/mailbox/pcc.c @@ -0,0 +1,403 @@ +/* + * Copyright (C) 2014 Linaro Ltd. + * Author: Ashwin Chaugule + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * 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. + * + * PCC (Platform Communication Channel) is defined in the ACPI 5.0+ + * specification. It is a mailbox like mechanism to allow clients + * such as CPPC (Collaborative Processor Performance Control), RAS + * (Reliability, Availability and Serviceability) and MPST (Memory + * Node Power State Table) to talk to the platform (e.g. BMC) through + * shared memory regions as defined in the PCC table entries. The PCC + * specification supports a Doorbell mechanism for the PCC clients + * to notify the platform about new data. This Doorbell information + * is also specified in each PCC table entry. See pcc_send_data() + * and pcc_tx_done() for basic mode of operation. + * + * For more details about PCC, please see the ACPI specification from + * http://www.uefi.org/ACPIv5.1 Section 14. + * + * This file implements PCC as a Mailbox controller and allows for PCC + * clients to be implemented as its Mailbox Client Channels. + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#include "mailbox.h" + +#define MAX_PCC_SUBSPACES 256 +#define PCCS_SS_SIG_MAGIC 0x50434300 +#define PCC_CMD_COMPLETE 0x1 + +static struct mbox_chan *pcc_mbox_channels; + +static struct mbox_controller pcc_mbox_ctrl = {}; +/** + * get_pcc_channel - Given a PCC subspace idx, get + * the respective mbox_channel. + * @id: PCC subspace index. + * + * Return: ERR_PTR(errno) if error, else pointer + * to mbox channel. + */ +static struct mbox_chan *get_pcc_channel(int id) +{ + struct mbox_chan *pcc_chan; + + if (id < 0 || id > pcc_mbox_ctrl.num_chans) + return ERR_PTR(-ENOENT); + + pcc_chan = (struct mbox_chan *) + (unsigned long) pcc_mbox_channels + + (id * sizeof(*pcc_chan)); + + return pcc_chan; +} + +/** + * get_subspace_id - Given a Mailbox channel, find out the + * PCC subspace id. + * @chan: Pointer to Mailbox Channel from which we want + * the index. + * Return: Errno if not found, else positive index number. + */ +static int get_subspace_id(struct mbox_chan *chan) +{ + unsigned int id = chan - pcc_mbox_channels; + + if (id < 0 || id > pcc_mbox_ctrl.num_chans) + return -ENOENT; + + return id; +} + +/** + * pcc_mbox_request_channel - PCC clients call this function to + * request a pointer to their PCC subspace, from which they + * can get the details of communicating with the remote. + * @cl: Pointer to Mailbox client, so we know where to bind the + * Channel. + * @subspace_id: The PCC Subspace index as parsed in the PCC client + * ACPI package. This is used to lookup the array of PCC + * subspaces as parsed by the PCC Mailbox controller. + * + * Return: Pointer to the Mailbox Channel if successful or + * ERR_PTR. + */ +struct mbox_chan *pcc_mbox_request_channel(struct mbox_client *cl, + int subspace_id) +{ + struct device *dev = pcc_mbox_ctrl.dev; + struct mbox_chan *chan; + unsigned long flags; + + /* + * Each PCC Subspace is a Mailbox Channel. + * The PCC Clients get their PCC Subspace ID + * from their own tables and pass it here. + * This returns a pointer to the PCC subspace + * for the Client to operate on. + */ + chan = get_pcc_channel(subspace_id); + + if (!chan || chan->cl) { + dev_err(dev, "%s: PCC mailbox not free\n", __func__); + return ERR_PTR(-EBUSY); + } + + spin_lock_irqsave(&chan->lock, flags); + chan->msg_free = 0; + chan->msg_count = 0; + chan->active_req = NULL; + chan->cl = cl; + init_completion(&chan->tx_complete); + + if (chan->txdone_method == TXDONE_BY_POLL && cl->knows_txdone) + chan->txdone_method |= TXDONE_BY_ACK; + + spin_unlock_irqrestore(&chan->lock, flags); + + return chan; +} +EXPORT_SYMBOL_GPL(pcc_mbox_request_channel); + +/** + * pcc_mbox_free_channel - Clients call this to free their Channel. + * + * @chan: Pointer to the mailbox channel as returned by + * pcc_mbox_request_channel() + */ +void pcc_mbox_free_channel(struct mbox_chan *chan) +{ + unsigned long flags; + + if (!chan || !chan->cl) + return; + + spin_lock_irqsave(&chan->lock, flags); + chan->cl = NULL; + chan->active_req = NULL; + if (chan->txdone_method == (TXDONE_BY_POLL | TXDONE_BY_ACK)) + chan->txdone_method = TXDONE_BY_POLL; + + spin_unlock_irqrestore(&chan->lock, flags); +} +EXPORT_SYMBOL_GPL(pcc_mbox_free_channel); + +/** + * pcc_tx_done - Callback from Mailbox controller code to + * check if PCC message transmission completed. + * @chan: Pointer to Mailbox channel on which previous + * transmission occurred. + * + * Return: TRUE if succeeded. + */ +static bool pcc_tx_done(struct mbox_chan *chan) +{ + struct acpi_pcct_hw_reduced *pcct_ss = chan->con_priv; + struct acpi_pcct_shared_memory *generic_comm_base = + (struct acpi_pcct_shared_memory *) pcct_ss->base_address; + u16 cmd_delay = pcct_ss->latency; + unsigned int retries = 0; + + /* Try a few times while waiting for platform to consume */ + while (!(readw_relaxed(&generic_comm_base->status) + & PCC_CMD_COMPLETE)) { + + if (retries++ < 5) + udelay(cmd_delay); + else { + /* + * If the remote is dead, this will cause the Mbox + * controller to timeout after mbox client.tx_tout + * msecs. + */ + pr_err("PCC platform did not respond.\n"); + return false; + } + } + return true; +} + +/** + * pcc_send_data - Called from Mailbox Controller code to finally + * transmit data over channel. + * @chan: Pointer to Mailbox channel over which to send data. + * @data: Actual data to be written over channel. + * + * Return: Err if something failed else 0 for success. + */ +static int pcc_send_data(struct mbox_chan *chan, void *data) +{ + struct acpi_pcct_hw_reduced *pcct_ss = chan->con_priv; + struct acpi_pcct_shared_memory *generic_comm_base = + (struct acpi_pcct_shared_memory *) pcct_ss->base_address; + struct acpi_generic_address doorbell; + u64 doorbell_preserve; + u64 doorbell_val; + u64 doorbell_write; + u16 cmd = *(u16 *) data; + u16 ss_idx = -1; + + ss_idx = get_subspace_id(chan); + + if (ss_idx < 0) { + pr_err("Invalid Subspace ID from PCC client\n"); + return -EINVAL; + } + + doorbell = pcct_ss->doorbell_register; + doorbell_preserve = pcct_ss->preserve_mask; + doorbell_write = pcct_ss->write_mask; + + /* Write to the shared comm region. */ + writew(cmd, &generic_comm_base->command); + + /* Write Subspace MAGIC value so platform can identify destination. */ + writel((PCCS_SS_SIG_MAGIC | ss_idx), &generic_comm_base->signature); + + /* Flip CMD COMPLETE bit */ + writew(0, &generic_comm_base->status); + + /* Sync notification from OSPM to Platform. */ + acpi_read(&doorbell_val, &doorbell); + acpi_write((doorbell_val & doorbell_preserve) | doorbell_write, + &doorbell); + + return 0; +} + +static struct mbox_chan_ops pcc_chan_ops = { + .send_data = pcc_send_data, + .last_tx_done = pcc_tx_done, +}; + +/** + * parse_pcc_subspace - Parse the PCC table and verify PCC subspace + * entries. There should be one entry per PCC client. + * @header: Pointer to the ACPI subtable header under the PCCT. + * @end: End of subtable entry. + * + * Return: 0 for Success, else errno. + * + * This gets called for each entry in the PCC table. + */ +static int parse_pcc_subspace(struct acpi_subtable_header *header, + const unsigned long end) +{ + struct acpi_pcct_hw_reduced *pcct_ss; + + if (pcc_mbox_ctrl.num_chans <= MAX_PCC_SUBSPACES) { + pcct_ss = (struct acpi_pcct_hw_reduced *) header; + + if (pcct_ss->header.type != + ACPI_PCCT_TYPE_HW_REDUCED_SUBSPACE) { + pr_err("Incorrect PCC Subspace type detected\n"); + return -EINVAL; + } + } + + return 0; +} + +/** + * acpi_pcc_probe - Parse the ACPI tree for the PCCT. + * + * Return: 0 for Success, else errno. + */ +static int __init acpi_pcc_probe(void) +{ + acpi_size pcct_tbl_header_size; + struct acpi_table_header *pcct_tbl; + struct acpi_subtable_header *pcct_entry; + int count, i; + acpi_status status = AE_OK; + + /* Search for PCCT */ + status = acpi_get_table_with_size(ACPI_SIG_PCCT, 0, + &pcct_tbl, + &pcct_tbl_header_size); + + if (ACPI_FAILURE(status) || !pcct_tbl) { + pr_warn("PCCT header not found.\n"); + return -ENODEV; + } + + count = acpi_table_parse_entries(ACPI_SIG_PCCT, + sizeof(struct acpi_table_pcct), + ACPI_PCCT_TYPE_HW_REDUCED_SUBSPACE, + parse_pcc_subspace, MAX_PCC_SUBSPACES); + + if (count <= 0) { + pr_err("Error parsing PCC subspaces from PCCT\n"); + return -EINVAL; + } + + pcc_mbox_channels = kzalloc(sizeof(struct mbox_chan) * + count, GFP_KERNEL); + + if (!pcc_mbox_channels) { + pr_err("Could not allocate space for PCC mbox channels\n"); + return -ENOMEM; + } + + /* Point to the first PCC subspace entry */ + pcct_entry = (struct acpi_subtable_header *) ( + (unsigned long) pcct_tbl + sizeof(struct acpi_table_pcct)); + + for (i = 0; i < count; i++) { + pcc_mbox_channels[i].con_priv = pcct_entry; + pcct_entry = (struct acpi_subtable_header *) + ((unsigned long) pcct_entry + pcct_entry->length); + } + + pcc_mbox_ctrl.num_chans = count; + + pr_info("Detected %d PCC Subspaces\n", pcc_mbox_ctrl.num_chans); + + return 0; +} + +/** + * pcc_mbox_probe - Called when we find a match for the + * PCCT platform device. This is purely used to represent + * the PCCT as a virtual device for registering with the + * generic Mailbox framework. + * + * @pdev: Pointer to platform device returned when a match + * is found. + * + * Return: 0 for Success, else errno. + */ +static int pcc_mbox_probe(struct platform_device *pdev) +{ + int ret = 0; + + pcc_mbox_ctrl.chans = pcc_mbox_channels; + pcc_mbox_ctrl.ops = &pcc_chan_ops; + pcc_mbox_ctrl.txdone_poll = true; + pcc_mbox_ctrl.txpoll_period = 10; + pcc_mbox_ctrl.dev = &pdev->dev; + + pr_info("Registering PCC driver as Mailbox controller\n"); + ret = mbox_controller_register(&pcc_mbox_ctrl); + + if (ret) { + pr_err("Err registering PCC as Mailbox controller: %d\n", ret); + ret = -ENODEV; + } + + return ret; +} + +struct platform_driver pcc_mbox_driver = { + .probe = pcc_mbox_probe, + .driver = { + .name = "PCCT", + .owner = THIS_MODULE, + }, +}; + +static int __init pcc_init(void) +{ + int ret; + struct platform_device *pcc_pdev; + + if (acpi_disabled) + return -ENODEV; + + /* Check if PCC support is available. */ + ret = acpi_pcc_probe(); + + if (ret) { + pr_err("ACPI PCC probe failed.\n"); + return -ENODEV; + } + + pcc_pdev = platform_create_bundle(&pcc_mbox_driver, + pcc_mbox_probe, NULL, 0, NULL, 0); + + if (!pcc_pdev) { + pr_err("Err creating PCC platform bundle\n"); + return -ENODEV; + } + + return 0; +} +device_initcall(pcc_init); -- cgit v1.2.3-59-g8ed1b