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Release 4.7 drivers/mailbox/ti-msgmgr.c

Directory: drivers/mailbox
/*
 * Texas Instruments' Message Manager Driver
 *
 * Copyright (C) 2015-2016 Texas Instruments Incorporated - http://www.ti.com/
 *      Nishanth Menon
 *
 * 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.
 *
 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
 * kind, whether express or implied; without even the implied warranty
 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */


#define pr_fmt(fmt) "%s: " fmt, __func__

#include <linux/device.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/mailbox_controller.h>
#include <linux/module.h>
#include <linux/of_device.h>
#include <linux/of.h>
#include <linux/of_irq.h>
#include <linux/platform_device.h>
#include <linux/soc/ti/ti-msgmgr.h>


#define Q_DATA_OFFSET(proxy, queue, reg)	\
		     ((0x10000 * (proxy)) + (0x80 * (queue)) + ((reg) * 4))

#define Q_STATE_OFFSET(queue)			((queue) * 0x4)

#define Q_STATE_ENTRY_COUNT_MASK		(0xFFF000)

/**
 * struct ti_msgmgr_valid_queue_desc - SoC valid queues meant for this processor
 * @queue_id:   Queue Number for this path
 * @proxy_id:   Proxy ID representing the processor in SoC
 * @is_tx:      Is this a receive path?
 */

struct ti_msgmgr_valid_queue_desc {
	
u8 queue_id;
	
u8 proxy_id;
	
bool is_tx;
};

/**
 * struct ti_msgmgr_desc - Description of message manager integration
 * @queue_count:        Number of Queues
 * @max_message_size:   Message size in bytes
 * @max_messages:       Number of messages
 * @q_slices:           Number of queue engines
 * @q_proxies:          Number of queue proxies per page
 * @data_first_reg:     First data register for proxy data region
 * @data_last_reg:      Last data register for proxy data region
 * @tx_polled:          Do I need to use polled mechanism for tx
 * @tx_poll_timeout_ms: Timeout in ms if polled
 * @valid_queues:       List of Valid queues that the processor can access
 * @num_valid_queues:   Number of valid queues
 *
 * This structure is used in of match data to describe how integration
 * for a specific compatible SoC is done.
 */

struct ti_msgmgr_desc {
	
u8 queue_count;
	
u8 max_message_size;
	
u8 max_messages;
	
u8 q_slices;
	
u8 q_proxies;
	
u8 data_first_reg;
	
u8 data_last_reg;
	
bool tx_polled;
	
int tx_poll_timeout_ms;
	
const struct ti_msgmgr_valid_queue_desc *valid_queues;
	
int num_valid_queues;
};

/**
 * struct ti_queue_inst - Description of a queue instance
 * @name:       Queue Name
 * @queue_id:   Queue Identifier as mapped on SoC
 * @proxy_id:   Proxy Identifier as mapped on SoC
 * @irq:        IRQ for Rx Queue
 * @is_tx:      'true' if transmit queue, else, 'false'
 * @queue_buff_start: First register of Data Buffer
 * @queue_buff_end: Last (or confirmation) register of Data buffer
 * @queue_state: Queue status register
 * @chan:       Mailbox channel
 * @rx_buff:    Receive buffer pointer allocated at probe, max_message_size
 */

struct ti_queue_inst {
	
char name[30];
	
u8 queue_id;
	
u8 proxy_id;
	
int irq;
	
bool is_tx;
	
void __iomem *queue_buff_start;
	
void __iomem *queue_buff_end;
	
void __iomem *queue_state;
	
struct mbox_chan *chan;
	
u32 *rx_buff;
};

/**
 * struct ti_msgmgr_inst - Description of a Message Manager Instance
 * @dev:        device pointer corresponding to the Message Manager instance
 * @desc:       Description of the SoC integration
 * @queue_proxy_region: Queue proxy region where queue buffers are located
 * @queue_state_debug_region:   Queue status register regions
 * @num_valid_queues:   Number of valid queues defined for the processor
 *              Note: other queues are probably reserved for other processors
 *              in the SoC.
 * @qinsts:     Array of valid Queue Instances for the Processor
 * @mbox:       Mailbox Controller
 * @chans:      Array for channels corresponding to the Queue Instances.
 */

struct ti_msgmgr_inst {
	
struct device *dev;
	
const struct ti_msgmgr_desc *desc;
	
void __iomem *queue_proxy_region;
	
void __iomem *queue_state_debug_region;
	
u8 num_valid_queues;
	
struct ti_queue_inst *qinsts;
	
struct mbox_controller mbox;
	
struct mbox_chan *chans;
};

/**
 * ti_msgmgr_queue_get_num_messages() - Get the number of pending messages
 * @qinst:      Queue instance for which we check the number of pending messages
 *
 * Return: number of messages pending in the queue (0 == no pending messages)
 */

static inline int ti_msgmgr_queue_get_num_messages(struct ti_queue_inst *qinst) { u32 val; /* * We cannot use relaxed operation here - update may happen * real-time. */ val = readl(qinst->queue_state) & Q_STATE_ENTRY_COUNT_MASK; val >>= __ffs(Q_STATE_ENTRY_COUNT_MASK); return val; }

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/** * ti_msgmgr_queue_rx_interrupt() - Interrupt handler for receive Queue * @irq: Interrupt number * @p: Channel Pointer * * Return: -EINVAL if there is no instance * IRQ_NONE if the interrupt is not ours. * IRQ_HANDLED if the rx interrupt was successfully handled. */
static irqreturn_t ti_msgmgr_queue_rx_interrupt(int irq, void *p) { struct mbox_chan *chan = p; struct device *dev = chan->mbox->dev; struct ti_msgmgr_inst *inst = dev_get_drvdata(dev); struct ti_queue_inst *qinst = chan->con_priv; const struct ti_msgmgr_desc *desc; int msg_count, num_words; struct ti_msgmgr_message message; void __iomem *data_reg; u32 *word_data; if (WARN_ON(!inst)) { dev_err(dev, "no platform drv data??\n"); return -EINVAL; } /* Do I have an invalid interrupt source? */ if (qinst->is_tx) { dev_err(dev, "Cannot handle rx interrupt on tx channel %s\n", qinst->name); return IRQ_NONE; } /* Do I actually have messages to read? */ msg_count = ti_msgmgr_queue_get_num_messages(qinst); if (!msg_count) { /* Shared IRQ? */ dev_dbg(dev, "Spurious event - 0 pending data!\n"); return IRQ_NONE; } /* * I have no idea about the protocol being used to communicate with the * remote producer - 0 could be valid data, so I wont make a judgement * of how many bytes I should be reading. Let the client figure this * out.. I just read the full message and pass it on.. */ desc = inst->desc; message.len = desc->max_message_size; message.buf = (u8 *)qinst->rx_buff; /* * NOTE about register access involved here: * the hardware block is implemented with 32bit access operations and no * support for data splitting. We don't want the hardware to misbehave * with sub 32bit access - For example: if the last register read is * split into byte wise access, it can result in the queue getting * stuck or indeterminate behavior. An out of order read operation may * result in weird data results as well. * Hence, we do not use memcpy_fromio or __ioread32_copy here, instead * we depend on readl for the purpose. * * Also note that the final register read automatically marks the * queue message as read. */ for (data_reg = qinst->queue_buff_start, word_data = qinst->rx_buff, num_words = (desc->max_message_size / sizeof(u32)); num_words; num_words--, data_reg += sizeof(u32), word_data++) *word_data = readl(data_reg); /* * Last register read automatically clears the IRQ if only 1 message * is pending - so send the data up the stack.. * NOTE: Client is expected to be as optimal as possible, since * we invoke the handler in IRQ context. */ mbox_chan_received_data(chan, (void *)&message); return IRQ_HANDLED; }

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/** * ti_msgmgr_queue_peek_data() - Peek to see if there are any rx messages. * @chan: Channel Pointer * * Return: 'true' if there is pending rx data, 'false' if there is none. */
static bool ti_msgmgr_queue_peek_data(struct mbox_chan *chan) { struct ti_queue_inst *qinst = chan->con_priv; int msg_count; if (qinst->is_tx) return false; msg_count = ti_msgmgr_queue_get_num_messages(qinst); return msg_count ? true : false; }

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/** * ti_msgmgr_last_tx_done() - See if all the tx messages are sent * @chan: Channel pointer * * Return: 'true' is no pending tx data, 'false' if there are any. */
static bool ti_msgmgr_last_tx_done(struct mbox_chan *chan) { struct ti_queue_inst *qinst = chan->con_priv; int msg_count; if (!qinst->is_tx) return false; msg_count = ti_msgmgr_queue_get_num_messages(qinst); /* if we have any messages pending.. */ return msg_count ? false : true; }

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/** * ti_msgmgr_send_data() - Send data * @chan: Channel Pointer * @data: ti_msgmgr_message * Message Pointer * * Return: 0 if all goes good, else appropriate error messages. */
static int ti_msgmgr_send_data(struct mbox_chan *chan, void *data) { struct device *dev = chan->mbox->dev; struct ti_msgmgr_inst *inst = dev_get_drvdata(dev); const struct ti_msgmgr_desc *desc; struct ti_queue_inst *qinst = chan->con_priv; int num_words, trail_bytes; struct ti_msgmgr_message *message = data; void __iomem *data_reg; u32 *word_data; if (WARN_ON(!inst)) { dev_err(dev, "no platform drv data??\n"); return -EINVAL; } desc = inst->desc; if (desc->max_message_size < message->len) { dev_err(dev, "Queue %s message length %d > max %d\n", qinst->name, message->len, desc->max_message_size); return -EINVAL; } /* NOTE: Constraints similar to rx path exists here as well */ for (data_reg = qinst->queue_buff_start, num_words = message->len / sizeof(u32), word_data = (u32 *)message->buf; num_words; num_words--, data_reg += sizeof(u32), word_data++) writel(*word_data, data_reg); trail_bytes = message->len % sizeof(u32); if (trail_bytes) { u32 data_trail = *word_data; /* Ensure all unused data is 0 */ data_trail &= 0xFFFFFFFF >> (8 * (sizeof(u32) - trail_bytes)); writel(data_trail, data_reg); data_reg++; } /* * 'data_reg' indicates next register to write. If we did not already * write on tx complete reg(last reg), we must do so for transmit */ if (data_reg <= qinst->queue_buff_end) writel(0, qinst->queue_buff_end); return 0; }

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/** * ti_msgmgr_queue_startup() - Startup queue * @chan: Channel pointer * * Return: 0 if all goes good, else return corresponding error message */
static int ti_msgmgr_queue_startup(struct mbox_chan *chan) { struct ti_queue_inst *qinst = chan->con_priv; struct device *dev = chan->mbox->dev; int ret; if (!qinst->is_tx) { /* * With the expectation that the IRQ might be shared in SoC */ ret = request_irq(qinst->irq, ti_msgmgr_queue_rx_interrupt, IRQF_SHARED, qinst->name, chan); if (ret) { dev_err(dev, "Unable to get IRQ %d on %s(res=%d)\n", qinst->irq, qinst->name, ret); return ret; } } return 0; }

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/** * ti_msgmgr_queue_shutdown() - Shutdown the queue * @chan: Channel pointer */
static void ti_msgmgr_queue_shutdown(struct mbox_chan *chan) { struct ti_queue_inst *qinst = chan->con_priv; if (!qinst->is_tx) free_irq(qinst->irq, chan); }

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/** * ti_msgmgr_of_xlate() - Translation of phandle to queue * @mbox: Mailbox controller * @p: phandle pointer * * Return: Mailbox channel corresponding to the queue, else return error * pointer. */
static struct mbox_chan *ti_msgmgr_of_xlate(struct mbox_controller *mbox, const struct of_phandle_args *p) { struct ti_msgmgr_inst *inst; int req_qid, req_pid; struct ti_queue_inst *qinst; int i; inst = container_of(mbox, struct ti_msgmgr_inst, mbox); if (WARN_ON(!inst)) return ERR_PTR(-EINVAL); /* #mbox-cells is 2 */ if (p->args_count != 2) { dev_err(inst->dev, "Invalid arguments in dt[%d] instead of 2\n", p->args_count); return ERR_PTR(-EINVAL); } req_qid = p->args[0]; req_pid = p->args[1]; for (qinst = inst->qinsts, i = 0; i < inst->num_valid_queues; i++, qinst++) { if (req_qid == qinst->queue_id && req_pid == qinst->proxy_id) return qinst->chan; } dev_err(inst->dev, "Queue ID %d, Proxy ID %d is wrong on %s\n", req_qid, req_pid, p->np->name); return ERR_PTR(-ENOENT); }

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/** * ti_msgmgr_queue_setup() - Setup data structures for each queue instance * @idx: index of the queue * @dev: pointer to the message manager device * @np: pointer to the of node * @inst: Queue instance pointer * @d: Message Manager instance description data * @qd: Queue description data * @qinst: Queue instance pointer * @chan: pointer to mailbox channel * * Return: 0 if all went well, else return corresponding error */
static int ti_msgmgr_queue_setup(int idx, struct device *dev, struct device_node *np, struct ti_msgmgr_inst *inst, const struct ti_msgmgr_desc *d, const struct ti_msgmgr_valid_queue_desc *qd, struct ti_queue_inst *qinst, struct mbox_chan *chan) { qinst->proxy_id = qd->proxy_id; qinst->queue_id = qd->queue_id; if (qinst->queue_id > d->queue_count) { dev_err(dev, "Queue Data [idx=%d] queuid %d > %d\n", idx, qinst->queue_id, d->queue_count); return -ERANGE; } qinst->is_tx = qd->is_tx; snprintf(qinst->name, sizeof(qinst->name), "%s %s_%03d_%03d", dev_name(dev), qinst->is_tx ? "tx" : "rx", qinst->queue_id, qinst->proxy_id); if (!qinst->is_tx) { char of_rx_irq_name[7]; snprintf(of_rx_irq_name, sizeof(of_rx_irq_name), "rx_%03d", qinst->queue_id); qinst->irq = of_irq_get_byname(np, of_rx_irq_name); if (qinst->irq < 0) { dev_crit(dev, "[%d]QID %d PID %d:No IRQ[%s]: %d\n", idx, qinst->queue_id, qinst->proxy_id, of_rx_irq_name, qinst->irq); return qinst->irq; } /* Allocate usage buffer for rx */ qinst->rx_buff = devm_kzalloc(dev, d->max_message_size, GFP_KERNEL); if (!qinst->rx_buff) return -ENOMEM; } qinst->queue_buff_start = inst->queue_proxy_region + Q_DATA_OFFSET(qinst->proxy_id, qinst->queue_id, d->data_first_reg); qinst->queue_buff_end = inst->queue_proxy_region + Q_DATA_OFFSET(qinst->proxy_id, qinst->queue_id, d->data_last_reg); qinst->queue_state = inst->queue_state_debug_region + Q_STATE_OFFSET(qinst->queue_id); qinst->chan = chan; chan->con_priv = qinst; dev_dbg(dev, "[%d] qidx=%d pidx=%d irq=%d q_s=%p q_e = %p\n", idx, qinst->queue_id, qinst->proxy_id, qinst->irq, qinst->queue_buff_start, qinst->queue_buff_end); return 0; }

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/* Queue operations */ static const struct mbox_chan_ops ti_msgmgr_chan_ops = { .startup = ti_msgmgr_queue_startup, .shutdown = ti_msgmgr_queue_shutdown, .peek_data = ti_msgmgr_queue_peek_data, .last_tx_done = ti_msgmgr_last_tx_done, .send_data = ti_msgmgr_send_data, }; /* Keystone K2G SoC integration details */ static const struct ti_msgmgr_valid_queue_desc k2g_valid_queues[] = { {.queue_id = 0, .proxy_id = 0, .is_tx = true,}, {.queue_id = 1, .proxy_id = 0, .is_tx = true,}, {.queue_id = 2, .proxy_id = 0, .is_tx = true,}, {.queue_id = 3, .proxy_id = 0, .is_tx = true,}, {.queue_id = 5, .proxy_id = 2, .is_tx = false,}, {.queue_id = 56, .proxy_id = 1, .is_tx = true,}, {.queue_id = 57, .proxy_id = 2, .is_tx = false,}, {.queue_id = 58, .proxy_id = 3, .is_tx = true,}, {.queue_id = 59, .proxy_id = 4, .is_tx = true,}, {.queue_id = 60, .proxy_id = 5, .is_tx = true,}, {.queue_id = 61, .proxy_id = 6, .is_tx = true,}, }; static const struct ti_msgmgr_desc k2g_desc = { .queue_count = 64, .max_message_size = 64, .max_messages = 128, .q_slices = 1, .q_proxies = 1, .data_first_reg = 16, .data_last_reg = 31, .tx_polled = false, .valid_queues = k2g_valid_queues, .num_valid_queues = ARRAY_SIZE(k2g_valid_queues), }; static const struct of_device_id ti_msgmgr_of_match[] = { {.compatible = "ti,k2g-message-manager", .data = &k2g_desc}, { /* Sentinel */ } }; MODULE_DEVICE_TABLE(of, ti_msgmgr_of_match);
static int ti_msgmgr_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; const struct of_device_id *of_id; struct device_node *np; struct resource *res; const struct ti_msgmgr_desc *desc; struct ti_msgmgr_inst *inst; struct ti_queue_inst *qinst; struct mbox_controller *mbox; struct mbox_chan *chans; int queue_count; int i; int ret = -EINVAL; const struct ti_msgmgr_valid_queue_desc *queue_desc; if (!dev->of_node) { dev_err(dev, "no OF information\n"); return -EINVAL; } np = dev->of_node; of_id = of_match_device(ti_msgmgr_of_match, dev); if (!of_id) { dev_err(dev, "OF data missing\n"); return -EINVAL; } desc = of_id->data; inst = devm_kzalloc(dev, sizeof(*inst), GFP_KERNEL); if (!inst) return -ENOMEM; inst->dev = dev; inst->desc = desc; res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "queue_proxy_region"); inst->queue_proxy_region = devm_ioremap_resource(dev, res); if (IS_ERR(inst->queue_proxy_region)) return PTR_ERR(inst->queue_proxy_region); res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "queue_state_debug_region"); inst->queue_state_debug_region = devm_ioremap_resource(dev, res); if (IS_ERR(inst->queue_state_debug_region)) return PTR_ERR(inst->queue_state_debug_region); dev_dbg(dev, "proxy region=%p, queue_state=%p\n", inst->queue_proxy_region, inst->queue_state_debug_region); queue_count = desc->num_valid_queues; if (!queue_count || queue_count > desc->queue_count) { dev_crit(dev, "Invalid Number of queues %d. Max %d\n", queue_count, desc->queue_count); return -ERANGE; } inst->num_valid_queues = queue_count; qinst = devm_kzalloc(dev, sizeof(*qinst) * queue_count, GFP_KERNEL); if (!qinst) return -ENOMEM; inst->qinsts = qinst; chans = devm_kzalloc(dev, sizeof(*chans) * queue_count, GFP_KERNEL); if (!chans) return -ENOMEM; inst->chans = chans; for (i = 0, queue_desc = desc->valid_queues; i < queue_count; i++, qinst++, chans++, queue_desc++) { ret = ti_msgmgr_queue_setup(i, dev, np, inst, desc, queue_desc, qinst, chans); if (ret) return ret; } mbox = &inst->mbox; mbox->dev = dev; mbox->ops = &ti_msgmgr_chan_ops; mbox->chans = inst->chans; mbox->num_chans = inst->num_valid_queues; mbox->txdone_irq = false; mbox->txdone_poll = desc->tx_polled; if (desc->tx_polled) mbox->txpoll_period = desc->tx_poll_timeout_ms; mbox->of_xlate = ti_msgmgr_of_xlate; platform_set_drvdata(pdev, inst); ret = mbox_controller_register(mbox); if (ret) dev_err(dev, "Failed to register mbox_controller(%d)\n", ret); return ret; }

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static int ti_msgmgr_remove(struct platform_device *pdev) { struct ti_msgmgr_inst *inst; inst = platform_get_drvdata(pdev); mbox_controller_unregister(&inst->mbox); return 0; }

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static struct platform_driver ti_msgmgr_driver = { .probe = ti_msgmgr_probe, .remove = ti_msgmgr_remove, .driver = { .name = "ti-msgmgr", .of_match_table = of_match_ptr(ti_msgmgr_of_match), }, }; module_platform_driver(ti_msgmgr_driver); MODULE_LICENSE("GPL v2"); MODULE_DESCRIPTION("TI message manager driver"); MODULE_AUTHOR("Nishanth Menon"); MODULE_ALIAS("platform:ti-msgmgr");

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Directory: drivers/mailbox
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