diff options
Diffstat (limited to 'drivers/mailbox')
| -rw-r--r-- | drivers/mailbox/Kconfig | 12 | ||||
| -rw-r--r-- | drivers/mailbox/Makefile | 2 | ||||
| -rw-r--r-- | drivers/mailbox/mailbox.c | 19 | ||||
| -rw-r--r-- | drivers/mailbox/mailbox.h | 14 | ||||
| -rw-r--r-- | drivers/mailbox/omap-mailbox.c | 346 | ||||
| -rw-r--r-- | drivers/mailbox/pcc.c | 403 |
6 files changed, 640 insertions, 156 deletions
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 afcb430508ec..59aad4d5da53 100644 --- a/drivers/mailbox/mailbox.c +++ b/drivers/mailbox/mailbox.c @@ -21,13 +21,13 @@ #include <linux/mailbox_client.h> #include <linux/mailbox_controller.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 */ +#include "mailbox.h" 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 +60,7 @@ 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); @@ -76,6 +76,8 @@ 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) { @@ -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; 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/omap-mailbox.c b/drivers/mailbox/omap-mailbox.c index 42978c4b63fc..0f332c178b07 100644 --- a/drivers/mailbox/omap-mailbox.c +++ b/drivers/mailbox/omap-mailbox.c @@ -29,13 +29,14 @@ #include <linux/slab.h> #include <linux/kfifo.h> #include <linux/err.h> -#include <linux/notifier.h> #include <linux/module.h> #include <linux/of_device.h> #include <linux/platform_device.h> #include <linux/pm_runtime.h> #include <linux/platform_data/mailbox-omap.h> #include <linux/omap-mailbox.h> +#include <linux/mailbox_controller.h> +#include <linux/mailbox_client.h> #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/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 <ashwin.chaugule@linaro.org> + * + * 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 <linux/acpi.h> +#include <linux/delay.h> +#include <linux/io.h> +#include <linux/init.h> +#include <linux/list.h> +#include <linux/platform_device.h> +#include <linux/mailbox_controller.h> +#include <linux/mailbox_client.h> + +#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); |