diff options
Diffstat (limited to 'drivers/soc/qcom')
| -rw-r--r-- | drivers/soc/qcom/Kconfig | 31 | ||||
| -rw-r--r-- | drivers/soc/qcom/Makefile | 3 | ||||
| -rw-r--r-- | drivers/soc/qcom/smd-rpm.c | 244 | ||||
| -rw-r--r-- | drivers/soc/qcom/smd.c | 1319 | ||||
| -rw-r--r-- | drivers/soc/qcom/smem.c | 775 |
5 files changed, 2372 insertions, 0 deletions
diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig index 5eea374c8fa6..ba47b70f4d85 100644 --- a/drivers/soc/qcom/Kconfig +++ b/drivers/soc/qcom/Kconfig @@ -13,7 +13,38 @@ config QCOM_GSBI config QCOM_PM bool "Qualcomm Power Management" depends on ARCH_QCOM && !ARM64 + select QCOM_SCM help QCOM Platform specific power driver to manage cores and L2 low power modes. It interface with various system drivers to put the cores in low power modes. + +config QCOM_SMD + tristate "Qualcomm Shared Memory Driver (SMD)" + depends on QCOM_SMEM + help + Say y here to enable support for the Qualcomm Shared Memory Driver + providing communication channels to remote processors in Qualcomm + platforms. + +config QCOM_SMD_RPM + tristate "Qualcomm Resource Power Manager (RPM) over SMD" + depends on QCOM_SMD && OF + help + If you say yes to this option, support will be included for the + Resource Power Manager system found in the Qualcomm 8974 based + devices. + + This is required to access many regulators, clocks and bus + frequencies controlled by the RPM on these devices. + + Say M here if you want to include support for the Qualcomm RPM as a + module. This will build a module called "qcom-smd-rpm". + +config QCOM_SMEM + tristate "Qualcomm Shared Memory Manager (SMEM)" + depends on ARCH_QCOM + help + Say y here to enable support for the Qualcomm Shared Memory Manager. + The driver provides an interface to items in a heap shared among all + processors in a Qualcomm platform. diff --git a/drivers/soc/qcom/Makefile b/drivers/soc/qcom/Makefile index 931d385386c5..10a93d168e0e 100644 --- a/drivers/soc/qcom/Makefile +++ b/drivers/soc/qcom/Makefile @@ -1,2 +1,5 @@ obj-$(CONFIG_QCOM_GSBI) += qcom_gsbi.o obj-$(CONFIG_QCOM_PM) += spm.o +obj-$(CONFIG_QCOM_SMD) += smd.o +obj-$(CONFIG_QCOM_SMD_RPM) += smd-rpm.o +obj-$(CONFIG_QCOM_SMEM) += smem.o diff --git a/drivers/soc/qcom/smd-rpm.c b/drivers/soc/qcom/smd-rpm.c new file mode 100644 index 000000000000..1392ccf14a20 --- /dev/null +++ b/drivers/soc/qcom/smd-rpm.c @@ -0,0 +1,244 @@ +/* + * Copyright (c) 2015, Sony Mobile Communications AB. + * Copyright (c) 2012-2013, The Linux Foundation. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 and + * only version 2 as published by the Free Software Foundation. + * + * 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. + */ + +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/of_platform.h> +#include <linux/io.h> +#include <linux/interrupt.h> + +#include <linux/soc/qcom/smd.h> +#include <linux/soc/qcom/smd-rpm.h> + +#define RPM_REQUEST_TIMEOUT (5 * HZ) + +/** + * struct qcom_smd_rpm - state of the rpm device driver + * @rpm_channel: reference to the smd channel + * @ack: completion for acks + * @lock: mutual exclusion around the send/complete pair + * @ack_status: result of the rpm request + */ +struct qcom_smd_rpm { + struct qcom_smd_channel *rpm_channel; + + struct completion ack; + struct mutex lock; + int ack_status; +}; + +/** + * struct qcom_rpm_header - header for all rpm requests and responses + * @service_type: identifier of the service + * @length: length of the payload + */ +struct qcom_rpm_header { + u32 service_type; + u32 length; +}; + +/** + * struct qcom_rpm_request - request message to the rpm + * @msg_id: identifier of the outgoing message + * @flags: active/sleep state flags + * @type: resource type + * @id: resource id + * @data_len: length of the payload following this header + */ +struct qcom_rpm_request { + u32 msg_id; + u32 flags; + u32 type; + u32 id; + u32 data_len; +}; + +/** + * struct qcom_rpm_message - response message from the rpm + * @msg_type: indicator of the type of message + * @length: the size of this message, including the message header + * @msg_id: message id + * @message: textual message from the rpm + * + * Multiple of these messages can be stacked in an rpm message. + */ +struct qcom_rpm_message { + u32 msg_type; + u32 length; + union { + u32 msg_id; + u8 message[0]; + }; +}; + +#define RPM_SERVICE_TYPE_REQUEST 0x00716572 /* "req\0" */ + +#define RPM_MSG_TYPE_ERR 0x00727265 /* "err\0" */ +#define RPM_MSG_TYPE_MSG_ID 0x2367736d /* "msg#" */ + +/** + * qcom_rpm_smd_write - write @buf to @type:@id + * @rpm: rpm handle + * @type: resource type + * @id: resource identifier + * @buf: the data to be written + * @count: number of bytes in @buf + */ +int qcom_rpm_smd_write(struct qcom_smd_rpm *rpm, + int state, + u32 type, u32 id, + void *buf, + size_t count) +{ + static unsigned msg_id = 1; + int left; + int ret; + + struct { + struct qcom_rpm_header hdr; + struct qcom_rpm_request req; + u8 payload[count]; + } pkt; + + /* SMD packets to the RPM may not exceed 256 bytes */ + if (WARN_ON(sizeof(pkt) >= 256)) + return -EINVAL; + + mutex_lock(&rpm->lock); + + pkt.hdr.service_type = RPM_SERVICE_TYPE_REQUEST; + pkt.hdr.length = sizeof(struct qcom_rpm_request) + count; + + pkt.req.msg_id = msg_id++; + pkt.req.flags = BIT(state); + pkt.req.type = type; + pkt.req.id = id; + pkt.req.data_len = count; + memcpy(pkt.payload, buf, count); + + ret = qcom_smd_send(rpm->rpm_channel, &pkt, sizeof(pkt)); + if (ret) + goto out; + + left = wait_for_completion_timeout(&rpm->ack, RPM_REQUEST_TIMEOUT); + if (!left) + ret = -ETIMEDOUT; + else + ret = rpm->ack_status; + +out: + mutex_unlock(&rpm->lock); + return ret; +} +EXPORT_SYMBOL(qcom_rpm_smd_write); + +static int qcom_smd_rpm_callback(struct qcom_smd_device *qsdev, + const void *data, + size_t count) +{ + const struct qcom_rpm_header *hdr = data; + const struct qcom_rpm_message *msg; + struct qcom_smd_rpm *rpm = dev_get_drvdata(&qsdev->dev); + const u8 *buf = data + sizeof(struct qcom_rpm_header); + const u8 *end = buf + hdr->length; + char msgbuf[32]; + int status = 0; + u32 len; + + if (hdr->service_type != RPM_SERVICE_TYPE_REQUEST || + hdr->length < sizeof(struct qcom_rpm_message)) { + dev_err(&qsdev->dev, "invalid request\n"); + return 0; + } + + while (buf < end) { + msg = (struct qcom_rpm_message *)buf; + switch (msg->msg_type) { + case RPM_MSG_TYPE_MSG_ID: + break; + case RPM_MSG_TYPE_ERR: + len = min_t(u32, ALIGN(msg->length, 4), sizeof(msgbuf)); + memcpy_fromio(msgbuf, msg->message, len); + msgbuf[len - 1] = 0; + + if (!strcmp(msgbuf, "resource does not exist")) + status = -ENXIO; + else + status = -EINVAL; + break; + } + + buf = PTR_ALIGN(buf + 2 * sizeof(u32) + msg->length, 4); + } + + rpm->ack_status = status; + complete(&rpm->ack); + return 0; +} + +static int qcom_smd_rpm_probe(struct qcom_smd_device *sdev) +{ + struct qcom_smd_rpm *rpm; + + rpm = devm_kzalloc(&sdev->dev, sizeof(*rpm), GFP_KERNEL); + if (!rpm) + return -ENOMEM; + + mutex_init(&rpm->lock); + init_completion(&rpm->ack); + + rpm->rpm_channel = sdev->channel; + + dev_set_drvdata(&sdev->dev, rpm); + + return of_platform_populate(sdev->dev.of_node, NULL, NULL, &sdev->dev); +} + +static void qcom_smd_rpm_remove(struct qcom_smd_device *sdev) +{ + of_platform_depopulate(&sdev->dev); +} + +static const struct of_device_id qcom_smd_rpm_of_match[] = { + { .compatible = "qcom,rpm-msm8974" }, + {} +}; +MODULE_DEVICE_TABLE(of, qcom_smd_rpm_of_match); + +static struct qcom_smd_driver qcom_smd_rpm_driver = { + .probe = qcom_smd_rpm_probe, + .remove = qcom_smd_rpm_remove, + .callback = qcom_smd_rpm_callback, + .driver = { + .name = "qcom_smd_rpm", + .owner = THIS_MODULE, + .of_match_table = qcom_smd_rpm_of_match, + }, +}; + +static int __init qcom_smd_rpm_init(void) +{ + return qcom_smd_driver_register(&qcom_smd_rpm_driver); +} +arch_initcall(qcom_smd_rpm_init); + +static void __exit qcom_smd_rpm_exit(void) +{ + qcom_smd_driver_unregister(&qcom_smd_rpm_driver); +} +module_exit(qcom_smd_rpm_exit); + +MODULE_AUTHOR("Bjorn Andersson <bjorn.andersson@sonymobile.com>"); +MODULE_DESCRIPTION("Qualcomm SMD backed RPM driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/soc/qcom/smd.c b/drivers/soc/qcom/smd.c new file mode 100644 index 000000000000..327adcf117c1 --- /dev/null +++ b/drivers/soc/qcom/smd.c @@ -0,0 +1,1319 @@ +/* + * Copyright (c) 2015, Sony Mobile Communications AB. + * Copyright (c) 2012-2013, The Linux Foundation. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 and + * only version 2 as published by the Free Software Foundation. + * + * 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. + */ + +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/mfd/syscon.h> +#include <linux/module.h> +#include <linux/of_irq.h> +#include <linux/of_platform.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/soc/qcom/smd.h> +#include <linux/soc/qcom/smem.h> +#include <linux/wait.h> + +/* + * The Qualcomm Shared Memory communication solution provides point-to-point + * channels for clients to send and receive streaming or packet based data. + * + * Each channel consists of a control item (channel info) and a ring buffer + * pair. The channel info carry information related to channel state, flow + * control and the offsets within the ring buffer. + * + * All allocated channels are listed in an allocation table, identifying the + * pair of items by name, type and remote processor. + * + * Upon creating a new channel the remote processor allocates channel info and + * ring buffer items from the smem heap and populate the allocation table. An + * interrupt is sent to the other end of the channel and a scan for new + * channels should be done. A channel never goes away, it will only change + * state. + * + * The remote processor signals it intent for bring up the communication + * channel by setting the state of its end of the channel to "opening" and + * sends out an interrupt. We detect this change and register a smd device to + * consume the channel. Upon finding a consumer we finish the handshake and the + * channel is up. + * + * Upon closing a channel, the remote processor will update the state of its + * end of the channel and signal us, we will then unregister any attached + * device and close our end of the channel. + * + * Devices attached to a channel can use the qcom_smd_send function to push + * data to the channel, this is done by copying the data into the tx ring + * buffer, updating the pointers in the channel info and signaling the remote + * processor. + * + * The remote processor does the equivalent when it transfer data and upon + * receiving the interrupt we check the channel info for new data and delivers + * this to the attached device. If the device is not ready to receive the data + * we leave it in the ring buffer for now. + */ + +struct smd_channel_info; +struct smd_channel_info_word; + +#define SMD_ALLOC_TBL_COUNT 2 +#define SMD_ALLOC_TBL_SIZE 64 + +/* + * This lists the various smem heap items relevant for the allocation table and + * smd channel entries. + */ +static const struct { + unsigned alloc_tbl_id; + unsigned info_base_id; + unsigned fifo_base_id; +} smem_items[SMD_ALLOC_TBL_COUNT] = { + { + .alloc_tbl_id = 13, + .info_base_id = 14, + .fifo_base_id = 338 + }, + { + .alloc_tbl_id = 14, + .info_base_id = 266, + .fifo_base_id = 202, + }, +}; + +/** + * struct qcom_smd_edge - representing a remote processor + * @smd: handle to qcom_smd + * @of_node: of_node handle for information related to this edge + * @edge_id: identifier of this edge + * @irq: interrupt for signals on this edge + * @ipc_regmap: regmap handle holding the outgoing ipc register + * @ipc_offset: offset within @ipc_regmap of the register for ipc + * @ipc_bit: bit in the register at @ipc_offset of @ipc_regmap + * @channels: list of all channels detected on this edge + * @channels_lock: guard for modifications of @channels + * @allocated: array of bitmaps representing already allocated channels + * @need_rescan: flag that the @work needs to scan smem for new channels + * @smem_available: last available amount of smem triggering a channel scan + * @work: work item for edge house keeping + */ +struct qcom_smd_edge { + struct qcom_smd *smd; + struct device_node *of_node; + unsigned edge_id; + + int irq; + + struct regmap *ipc_regmap; + int ipc_offset; + int ipc_bit; + + struct list_head channels; + spinlock_t channels_lock; + + DECLARE_BITMAP(allocated[SMD_ALLOC_TBL_COUNT], SMD_ALLOC_TBL_SIZE); + + bool need_rescan; + unsigned smem_available; + + struct work_struct work; +}; + +/* + * SMD channel states. + */ +enum smd_channel_state { + SMD_CHANNEL_CLOSED, + SMD_CHANNEL_OPENING, + SMD_CHANNEL_OPENED, + SMD_CHANNEL_FLUSHING, + SMD_CHANNEL_CLOSING, + SMD_CHANNEL_RESET, + SMD_CHANNEL_RESET_OPENING +}; + +/** + * struct qcom_smd_channel - smd channel struct + * @edge: qcom_smd_edge this channel is living on + * @qsdev: reference to a associated smd client device + * @name: name of the channel + * @state: local state of the channel + * @remote_state: remote state of the channel + * @tx_info: byte aligned outgoing channel info + * @rx_info: byte aligned incoming channel info + * @tx_info_word: word aligned outgoing channel info + * @rx_info_word: word aligned incoming channel info + * @tx_lock: lock to make writes to the channel mutually exclusive + * @fblockread_event: wakeup event tied to tx fBLOCKREADINTR + * @tx_fifo: pointer to the outgoing ring buffer + * @rx_fifo: pointer to the incoming ring buffer + * @fifo_size: size of each ring buffer + * @bounce_buffer: bounce buffer for reading wrapped packets + * @cb: callback function registered for this channel + * @recv_lock: guard for rx info modifications and cb pointer + * @pkt_size: size of the currently handled packet + * @list: lite entry for @channels in qcom_smd_edge + */ +struct qcom_smd_channel { + struct qcom_smd_edge *edge; + + struct qcom_smd_device *qsdev; + + char *name; + enum smd_channel_state state; + enum smd_channel_state remote_state; + + struct smd_channel_info *tx_info; + struct smd_channel_info *rx_info; + + struct smd_channel_info_word *tx_info_word; + struct smd_channel_info_word *rx_info_word; + + struct mutex tx_lock; + wait_queue_head_t fblockread_event; + + void *tx_fifo; + void *rx_fifo; + int fifo_size; + + void *bounce_buffer; + int (*cb)(struct qcom_smd_device *, const void *, size_t); + + spinlock_t recv_lock; + + int pkt_size; + + struct list_head list; +}; + +/** + * struct qcom_smd - smd struct + * @dev: device struct + * @num_edges: number of entries in @edges + * @edges: array of edges to be handled + */ +struct qcom_smd { + struct device *dev; + + unsigned num_edges; + struct qcom_smd_edge edges[0]; +}; + +/* + * Format of the smd_info smem items, for byte aligned channels. + */ +struct smd_channel_info { + u32 state; + u8 fDSR; + u8 fCTS; + u8 fCD; + u8 fRI; + u8 fHEAD; + u8 fTAIL; + u8 fSTATE; + u8 fBLOCKREADINTR; + u32 tail; + u32 head; +}; + +/* + * Format of the smd_info smem items, for word aligned channels. + */ +struct smd_channel_info_word { + u32 state; + u32 fDSR; + u32 fCTS; + u32 fCD; + u32 fRI; + u32 fHEAD; + u32 fTAIL; + u32 fSTATE; + u32 fBLOCKREADINTR; + u32 tail; + u32 head; +}; + +#define GET_RX_CHANNEL_INFO(channel, param) \ + (channel->rx_info_word ? \ + channel->rx_info_word->param : \ + channel->rx_info->param) + +#define SET_RX_CHANNEL_INFO(channel, param, value) \ + (channel->rx_info_word ? \ + (channel->rx_info_word->param = value) : \ + (channel->rx_info->param = value)) + +#define GET_TX_CHANNEL_INFO(channel, param) \ + (channel->tx_info_word ? \ + channel->tx_info_word->param : \ + channel->tx_info->param) + +#define SET_TX_CHANNEL_INFO(channel, param, value) \ + (channel->tx_info_word ? \ + (channel->tx_info_word->param = value) : \ + (channel->tx_info->param = value)) + +/** + * struct qcom_smd_alloc_entry - channel allocation entry + * @name: channel name + * @cid: channel index + * @flags: channel flags and edge id + * @ref_count: reference count of the channel + */ +struct qcom_smd_alloc_entry { + u8 name[20]; + u32 cid; + u32 flags; + u32 ref_count; +} __packed; + +#define SMD_CHANNEL_FLAGS_EDGE_MASK 0xff +#define SMD_CHANNEL_FLAGS_STREAM BIT(8) +#define SMD_CHANNEL_FLAGS_PACKET BIT(9) + +/* + * Each smd packet contains a 20 byte header, with the first 4 being the length + * of the packet. + */ +#define SMD_PACKET_HEADER_LEN 20 + +/* + * Signal the remote processor associated with 'channel'. + */ +static void qcom_smd_signal_channel(struct qcom_smd_channel *channel) +{ + struct qcom_smd_edge *edge = channel->edge; + + regmap_write(edge->ipc_regmap, edge->ipc_offset, BIT(edge->ipc_bit)); +} + +/* + * Initialize the tx channel info + */ +static void qcom_smd_channel_reset(struct qcom_smd_channel *channel) +{ + SET_TX_CHANNEL_INFO(channel, state, SMD_CHANNEL_CLOSED); + SET_TX_CHANNEL_INFO(channel, fDSR, 0); + SET_TX_CHANNEL_INFO(channel, fCTS, 0); + SET_TX_CHANNEL_INFO(channel, fCD, 0); + SET_TX_CHANNEL_INFO(channel, fRI, 0); + SET_TX_CHANNEL_INFO(channel, fHEAD, 0); + SET_TX_CHANNEL_INFO(channel, fTAIL, 0); + SET_TX_CHANNEL_INFO(channel, fSTATE, 1); + SET_TX_CHANNEL_INFO(channel, fBLOCKREADINTR, 0); + SET_TX_CHANNEL_INFO(channel, head, 0); + SET_TX_CHANNEL_INFO(channel, tail, 0); + + qcom_smd_signal_channel(channel); + + channel->state = SMD_CHANNEL_CLOSED; + channel->pkt_size = 0; +} + +/* + * Calculate the amount of data available in the rx fifo + */ +static size_t qcom_smd_channel_get_rx_avail(struct qcom_smd_channel *channel) +{ + unsigned head; + unsigned tail; + + head = GET_RX_CHANNEL_INFO(channel, head); + tail = GET_RX_CHANNEL_INFO(channel, tail); + + return (head - tail) & (channel->fifo_size - 1); +} + +/* + * Set tx channel state and inform the remote processor + */ +static void qcom_smd_channel_set_state(struct qcom_smd_channel *channel, + int state) +{ + struct qcom_smd_edge *edge = channel->edge; + bool is_open = state == SMD_CHANNEL_OPENED; + + if (channel->state == state) + return; + + dev_dbg(edge->smd->dev, "set_state(%s, %d)\n", channel->name, state); + + SET_TX_CHANNEL_INFO(channel, fDSR, is_open); + SET_TX_CHANNEL_INFO(channel, fCTS, is_open); + SET_TX_CHANNEL_INFO(channel, fCD, is_open); + + SET_TX_CHANNEL_INFO(channel, state, state); + SET_TX_CHANNEL_INFO(channel, fSTATE, 1); + + channel->state = state; + qcom_smd_signal_channel(channel); +} + +/* + * Copy count bytes of data using 32bit accesses, if that's required. + */ +static void smd_copy_to_fifo(void __iomem *_dst, + const void *_src, + size_t count, + bool word_aligned) +{ + u32 *dst = (u32 *)_dst; + u32 *src = (u32 *)_src; + + if (word_aligned) { + count /= sizeof(u32); + while (count--) + writel_relaxed(*src++, dst++); + } else { + memcpy_toio(_dst, _src, count); + } +} + +/* + * Copy count bytes of data using 32bit accesses, if that is required. + */ +static void smd_copy_from_fifo(void *_dst, + const void __iomem *_src, + size_t count, + bool word_aligned) +{ + u32 *dst = (u32 *)_dst; + u32 *src = (u32 *)_src; + + if (word_aligned) { + count /= sizeof(u32); + while (count--) + *dst++ = readl_relaxed(src++); + } else { + memcpy_fromio(_dst, _src, count); + } +} + +/* + * Read count bytes of data from the rx fifo into buf, but don't advance the + * tail. + */ +static size_t qcom_smd_channel_peek(struct qcom_smd_channel *channel, + void *buf, size_t count) +{ + bool word_aligned; + unsigned tail; + size_t len; + + word_aligned = channel->rx_info_word != NULL; + tail = GET_RX_CHANNEL_INFO(channel, tail); + + len = min_t(size_t, count, channel->fifo_size - tail); + if (len) { + smd_copy_from_fifo(buf, + channel->rx_fifo + tail, + len, + word_aligned); + } + + if (len != count) { + smd_copy_from_fifo(buf + len, + channel->rx_fifo, + count - len, + word_aligned); + } + + return count; +} + +/* + * Advance the rx tail by count bytes. + */ +static void qcom_smd_channel_advance(struct qcom_smd_channel *channel, + size_t count) +{ + unsigned tail; + + tail = GET_RX_CHANNEL_INFO(channel, tail); + tail += count; + tail &= (channel->fifo_size - 1); + SET_RX_CHANNEL_INFO(channel, tail, tail); +} + +/* + * Read out a single packet from the rx fifo and deliver it to the device + */ +static int qcom_smd_channel_recv_single(struct qcom_smd_channel *channel) +{ + struct qcom_smd_device *qsdev = channel->qsdev; + unsigned tail; + size_t len; + void *ptr; + int ret; + + if (!channel->cb) + return 0; + + tail = GET_RX_CHANNEL_INFO(channel, tail); + + /* Use bounce buffer if the data wraps */ + if (tail + channel->pkt_size >= channel->fifo_size) { + ptr = channel->bounce_buffer; + len = qcom_smd_channel_peek(channel, ptr, channel->pkt_size); + } else { + ptr = channel->rx_fifo + tail; + len = channel->pkt_size; + } + + ret = channel->cb(qsdev, ptr, len); + if (ret < 0) + return ret; + + /* Only forward the tail if the client consumed the data */ + qcom_smd_channel_advance(channel, len); + + channel->pkt_size = 0; + + return 0; +} + +/* + * Per channel interrupt handling + */ +static bool qcom_smd_channel_intr(struct qcom_smd_channel *channel) +{ + bool need_state_scan = false; + int remote_state; + u32 pktlen; + int avail; + int ret; + + /* Handle state changes */ + remote_state = GET_RX_CHANNEL_INFO(channel, state); + if (remote_state != channel->remote_state) { + channel->remote_state = remote_state; + need_state_scan = true; + } + /* Indicate that we have seen any state change */ + SET_RX_CHANNEL_INFO(channel, fSTATE, 0); + + /* Signal waiting qcom_smd_send() about the interrupt */ + if (!GET_TX_CHANNEL_INFO(channel, fBLOCKREADINTR)) + wake_up_interruptible(&channel->fblockread_event); + + /* Don't consume any data until we've opened the channel */ + if (channel->state != SMD_CHANNEL_OPENED) + goto out; + + /* Indicate that we've seen the new data */ + SET_RX_CHANNEL_INFO(channel, fHEAD, 0); + + /* Consume data */ + for (;;) { + avail = qcom_smd_channel_get_rx_avail(channel); + + if (!channel->pkt_size && avail >= SMD_PACKET_HEADER_LEN) { + qcom_smd_channel_peek(channel, &pktlen, sizeof(pktlen)); + qcom_smd_channel_advance(channel, SMD_PACKET_HEADER_LEN); + channel->pkt_size = pktlen; + } else if (channel->pkt_size && avail >= channel->pkt_size) { + ret = qcom_smd_channel_recv_single(channel); + if (ret) + break; + } else { + break; + } + } + + /* Indicate that we have seen and updated tail */ + SET_RX_CHANNEL_INFO(channel, fTAIL, 1); + + /* Signal the remote that we've consumed the data (if requested) */ + if (!GET_RX_CHANNEL_INFO(channel, fBLOCKREADINTR)) { + /* Ensure ordering of channel info updates */ + wmb(); + + qcom_smd_signal_channel(channel); + } + +out: + return need_state_scan; +} + +/* + * The edge interrupts are triggered by the remote processor on state changes, + * channel info updates or when new channels are created. + */ +static irqreturn_t qcom_smd_edge_intr(int irq, void *data) +{ + struct qcom_smd_edge *edge = data; + struct qcom_smd_channel *channel; + unsigned available; + bool kick_worker = false; + + /* + * Handle state changes or data on each of the channels on this edge + */ + spin_lock(&edge->channels_lock); + list_for_each_entry(channel, &edge->channels, list) { + spin_lock(&channel->recv_lock); + kick_worker |= qcom_smd_channel_intr(channel); + spin_unlock(&channel->recv_lock); + } + spin_unlock(&edge->channels_lock); + + /* + * Creating a new channel requires allocating an smem entry, so we only + * have to scan if the amount of available space in smem have changed + * since last scan. + */ + available = qcom_smem_get_free_space(edge->edge_id); + if (available != edge->smem_available) { + edge->smem_available = available; + edge->need_rescan = true; + kick_worker = true; + } + + if (kick_worker) + schedule_work(&edge->work); + + return IRQ_HANDLED; +} + +/* + * Delivers any outstanding packets in the rx fifo, can be used after probe of + * the clients to deliver any packets that wasn't delivered before the client + * was setup. + */ +static void qcom_smd_channel_resume(struct qcom_smd_channel *channel) +{ + unsigned long flags; + + spin_lock_irqsave(&channel->recv_lock, flags); + qcom_smd_channel_intr(channel); + spin_unlock_irqrestore(&channel->recv_lock, flags); +} + +/* + * Calculate how much space is available in the tx fifo. + */ +static size_t qcom_smd_get_tx_avail(struct qcom_smd_channel *channel) +{ + unsigned head; + unsigned tail; + unsigned mask = channel->fifo_size - 1; + + head = GET_TX_CHANNEL_INFO(channel, head); + tail = GET_TX_CHANNEL_INFO(channel, tail); + + return mask - ((head - tail) & mask); +} + +/* + * Write count bytes of data into channel, possibly wrapping in the ring buffer + */ +static int qcom_smd_write_fifo(struct qcom_smd_channel *channel, + const void *data, + size_t count) +{ + bool word_aligned; + unsigned head; + size_t len; + + word_aligned = channel->tx_info_word != NULL; + head = GET_TX_CHANNEL_INFO(channel, head); + + len = min_t(size_t, count, channel->fifo_size - head); + if (len) { + smd_copy_to_fifo(channel->tx_fifo + head, + data, + len, + word_aligned); + } + + if (len != count) { + smd_copy_to_fifo(channel->tx_fifo, + data + len, + count - len, + word_aligned); + } + + head += count; + head &= (channel->fifo_size - 1); + SET_TX_CHANNEL_INFO(channel, head, head); + + return count; +} + +/** + * qcom_smd_send - write data to smd channel + * @channel: channel handle + * @data: buffer of data to write + * @len: number of bytes to write + * + * This is a blocking write of len bytes into the channel's tx ring buffer and + * signal the remote end. It will sleep until there is enough space available + * in the tx buffer, utilizing the fBLOCKREADINTR signaling mechanism to avoid + * polling. + */ +int qcom_smd_send(struct qcom_smd_channel *channel, const void *data, int len) +{ + u32 hdr[5] = {len,}; + int tlen = sizeof(hdr) + len; + int ret; + + /* Word aligned channels only accept word size aligned data */ + if (channel->rx_info_word != NULL && len % 4) + return -EINVAL; + + ret = mutex_lock_interruptible(&channel->tx_lock); + if (ret) + return ret; + + while (qcom_smd_get_tx_avail(channel) < tlen) { + if (channel->state != SMD_CHANNEL_OPENED) { + ret = -EPIPE; + goto out; + } + + SET_TX_CHANNEL_INFO(channel, fBLOCKREADINTR, 1); + + ret = wait_event_interruptible(channel->fblockread_event, + qcom_smd_get_tx_avail(channel) >= tlen || + channel->state != SMD_CHANNEL_OPENED); + if (ret) + goto out; + + SET_TX_CHANNEL_INFO(channel, fBLOCKREADINTR, 0); + } + + SET_TX_CHANNEL_INFO(channel, fTAIL, 0); + + qcom_smd_write_fifo(channel, hdr, sizeof(hdr)); + qcom_smd_write_fifo(channel, data, len); + + SET_TX_CHANNEL_INFO(channel, fHEAD, 1); + + /* Ensure ordering of channel info updates */ + wmb(); + + qcom_smd_signal_channel(channel); + +out: + mutex_unlock(&channel->tx_lock); + + return ret; +} +EXPORT_SYMBOL(qcom_smd_send); + +static struct qcom_smd_device *to_smd_device(struct device *dev) +{ + return container_of(dev, struct qcom_smd_device, dev); +} + +static struct qcom_smd_driver *to_smd_driver(struct device *dev) +{ + struct qcom_smd_device *qsdev = to_smd_device(dev); + + return container_of(qsdev->dev.driver, struct qcom_smd_driver, driver); +} + +static int qcom_smd_dev_match(struct device *dev, struct device_driver *drv) +{ + return of_driver_match_device(dev, drv); +} + +/* + * Probe the smd client. + * + * The remote side have indicated that it want the channel to be opened, so + * complete the state handshake and probe our client driver. + */ +static int qcom_smd_dev_probe(struct device *dev) +{ + struct qcom_smd_device *qsdev = to_smd_device(dev); + struct qcom_smd_driver *qsdrv = to_smd_driver(dev); + struct qcom_smd_channel *channel = qsdev->channel; + size_t bb_size; + int ret; + + /* + * Packets are maximum 4k, but reduce if the fifo is smaller + */ + bb_size = min(channel->fifo_size, SZ_4K); + channel->bounce_buffer = kmalloc(bb_size, GFP_KERNEL); + if (!channel->bounce_buffer) + return -ENOMEM; + + channel->cb = qsdrv->callback; + + qcom_smd_channel_set_state(channel, SMD_CHANNEL_OPENING); + + qcom_smd_channel_set_state(channel, SMD_CHANNEL_OPENED); + + ret = qsdrv->probe(qsdev); + if (ret) + goto err; + + qcom_smd_channel_resume(channel); + + return 0; + +err: + dev_err(&qsdev->dev, "probe failed\n"); + + channel->cb = NULL; + kfree(channel->bounce_buffer); + channel->bounce_buffer = NULL; + + qcom_smd_channel_set_state(channel, SMD_CHANNEL_CLOSED); + return ret; +} + +/* + * Remove the smd client. + * + * The channel is going away, for some reason, so remove the smd client and + * reset the channel state. + */ +static int qcom_smd_dev_remove(struct device *dev) +{ + struct qcom_smd_device *qsdev = to_smd_device(dev); + struct qcom_smd_driver *qsdrv = to_smd_driver(dev); + struct qcom_smd_channel *channel = qsdev->channel; + unsigned long flags; + + qcom_smd_channel_set_state(channel, SMD_CHANNEL_CLOSING); + + /* + * Make sure we don't race with the code receiving data. + */ + spin_lock_irqsave(&channel->recv_lock, flags); + channel->cb = NULL; + spin_unlock_irqrestore(&channel->recv_lock, flags); + + /* Wake up any sleepers in qcom_smd_send() */ + wake_up_interruptible(&channel->fblockread_event); + + /* + * We expect that the client might block in remove() waiting for any + * outstanding calls to qcom_smd_send() to wake up and finish. + */ + if (qsdrv->remove) + qsdrv->remove(qsdev); + + /* + * The client is now gone, cleanup and reset the channel state. + */ + channel->qsdev = NULL; + kfree(channel->bounce_buffer); + channel->bounce_buffer = NULL; + + qcom_smd_channel_set_state(channel, SMD_CHANNEL_CLOSED); + + qcom_smd_channel_reset(channel); + + return 0; +} + +static struct bus_type qcom_smd_bus = { + .name = "qcom_smd", + .match = qcom_smd_dev_match, + .probe = qcom_smd_dev_probe, + .remove = qcom_smd_dev_remove, +}; + +/* + * Release function for the qcom_smd_device object. + */ +static void qcom_smd_release_device(struct device *dev) +{ + struct qcom_smd_device *qsdev = to_smd_device(dev); + + kfree(qsdev); +} + +/* + * Finds the device_node for the smd child interested in this channel. + */ +static struct device_node *qcom_smd_match_channel(struct device_node *edge_node, + const char *channel) +{ + struct device_node *child; + const char *name; + const char *key; + int ret; + + for_each_available_child_of_node(edge_node, child) { + key = "qcom,smd-channels"; + ret = of_property_read_string(child, key, &name); + if (ret) { + of_node_put(child); + continue; + } + + if (strcmp(name, channel) == 0) + return child; + } + + return NULL; +} + +/* + * Create a smd client device for channel that is being opened. + */ +static int qcom_smd_create_device(struct qcom_smd_channel *channel) +{ + struct qcom_smd_device *qsdev; + struct qcom_smd_edge *edge = channel->edge; + struct device_node *node; + struct qcom_smd *smd = edge->smd; + int ret; + + if (channel->qsdev) + return -EEXIST; + + node = qcom_smd_match_channel(edge->of_node, channel->name); + if (!node) { + dev_dbg(smd->dev, "no match for '%s'\n", channel->name); + return -ENXIO; + } + + dev_dbg(smd->dev, "registering '%s'\n", channel->name); + + qsdev = kzalloc(sizeof(*qsdev), GFP_KERNEL); + if (!qsdev) + return -ENOMEM; + + dev_set_name(&qsdev->dev, "%s.%s", edge->of_node->name, node->name); + qsdev->dev.parent = smd->dev; + qsdev->dev.bus = &qcom_smd_bus; + qsdev->dev.release = qcom_smd_release_device; + qsdev->dev.of_node = node; + + qsdev->channel = channel; + + channel->qsdev = qsdev; + + ret = device_register(&qsdev->dev); + if (ret) { + dev_err(smd->dev, "device_register failed: %d\n", ret); + put_device(&qsdev->dev); + } + + return ret; +} + +/* + * Destroy a smd client device for a channel that's going away. + */ +static void qcom_smd_destroy_device(struct qcom_smd_channel *channel) +{ + struct device *dev; + + BUG_ON(!channel->qsdev); + + dev = &channel->qsdev->dev; + + device_unregister(dev); + of_node_put(dev->of_node); + put_device(dev); +} + +/** + * qcom_smd_driver_register - register a smd driver + * @qsdrv: qcom_smd_driver struct + */ +int qcom_smd_driver_register(struct qcom_smd_driver *qsdrv) +{ + qsdrv->driver.bus = &qcom_smd_bus; + return driver_register(&qsdrv->driver); +} +EXPORT_SYMBOL(qcom_smd_driver_register); + +/** + * qcom_smd_driver_unregister - unregister a smd driver + * @qsdrv: qcom_smd_driver struct + */ +void qcom_smd_driver_unregister(struct qcom_smd_driver *qsdrv) +{ + driver_unregister(&qsdrv->driver); +} +EXPORT_SYMBOL(qcom_smd_driver_unregister); + +/* + * Allocate the qcom_smd_channel object for a newly found smd channel, + * retrieving and validating the smem items involved. + */ +static struct qcom_smd_channel *qcom_smd_create_channel(struct qcom_smd_edge *edge, + unsigned smem_info_item, + unsigned smem_fifo_item, + char *name) +{ + struct qcom_smd_channel *channel; + struct qcom_smd *smd = edge->smd; + size_t fifo_size; + size_t info_size; + void *fifo_base; + void *info; + int ret; + + channel = devm_kzalloc(smd->dev, sizeof(*channel), GFP_KERNEL); + if (!channel) + return ERR_PTR(-ENOMEM); + + channel->edge = edge; + channel->name = devm_kstrdup(smd->dev, name, GFP_KERNEL); + if (!channel->name) + return ERR_PTR(-ENOMEM); + + mutex_init(&channel->tx_lock); + spin_lock_init(&channel->recv_lock); + init_waitqueue_head(&channel->fblockread_event); + + ret = qcom_smem_get(edge->edge_id, smem_info_item, (void **)&info, &info_size); + if (ret) + goto free_name_and_channel; + + /* + * Use the size of the item to figure out which channel info struct to + * use. + */ + if (info_size == 2 * sizeof(struct smd_channel_info_word)) { + channel->tx_info_word = info; + channel->rx_info_word = info + sizeof(struct smd_channel_info_word); + } else if (info_size == 2 * sizeof(struct smd_channel_info)) { + channel->tx_info = info; + channel->rx_info = info + sizeof(struct smd_channel_info); + } else { + dev_err(smd->dev, + "channel info of size %zu not supported\n", info_size); + ret = -EINVAL; + goto free_name_and_channel; + } + + ret = qcom_smem_get(edge->edge_id, smem_fifo_item, &fifo_base, &fifo_size); + if (ret) + goto free_name_and_channel; + + /* The channel consist of a rx and tx fifo of equal size */ + fifo_size /= 2; + + dev_dbg(smd->dev, "new channel '%s' info-size: %zu fifo-size: %zu\n", + name, info_size, fifo_size); + + channel->tx_fifo = fifo_base; + channel->rx_fifo = fifo_base + fifo_size; + channel->fifo_size = fifo_size; + + qcom_smd_channel_reset(channel); + + return channel; + +free_name_and_channel: + devm_kfree(smd->dev, channel->name); + devm_kfree(smd->dev, channel); + + return ERR_PTR(ret); +} + +/* + * Scans the allocation table for any newly allocated channels, calls + * qcom_smd_create_channel() to create representations of these and add + * them to the edge's list of channels. + */ +static void qcom_discover_channels(struct qcom_smd_edge *edge) +{ + struct qcom_smd_alloc_entry *alloc_tbl; + struct qcom_smd_alloc_entry *entry; + struct qcom_smd_channel *channel; + struct qcom_smd *smd = edge->smd; + unsigned long flags; + unsigned fifo_id; + unsigned info_id; + int ret; + int tbl; + int i; + + for (tbl = 0; tbl < SMD_ALLOC_TBL_COUNT; tbl++) { + ret = qcom_smem_get(edge->edge_id, + smem_items[tbl].alloc_tbl_id, + (void **)&alloc_tbl, + NULL); + if (ret < 0) + continue; + + for (i = 0; i < SMD_ALLOC_TBL_SIZE; i++) { + entry = &alloc_tbl[i]; + if (test_bit(i, edge->allocated[tbl])) + continue; + + if (entry->ref_count == 0) + continue; + + if (!entry->name[0]) + continue; + + if (!(entry->flags & SMD_CHANNEL_FLAGS_PACKET)) + continue; + + if ((entry->flags & SMD_CHANNEL_FLAGS_EDGE_MASK) != edge->edge_id) + continue; + + info_id = smem_items[tbl].info_base_id + entry->cid; + fifo_id = smem_items[tbl].fifo_base_id + entry->cid; + + channel = qcom_smd_create_channel(edge, info_id, fifo_id, entry->name); + if (IS_ERR(channel)) + continue; + + spin_lock_irqsave(&edge->channels_lock, flags); + list_add(&channel->list, &edge->channels); + spin_unlock_irqrestore(&edge->channels_lock, flags); + + dev_dbg(smd->dev, "new channel found: '%s'\n", channel->name); + set_bit(i, edge->allocated[tbl]); + } + } + + schedule_work(&edge->work); +} + +/* + * This per edge worker scans smem for any new channels and register these. It + * then scans all registered channels for state changes that should be handled + * by creating or destroying smd client devices for the registered channels. + * + * LOCKING: edge->channels_lock is not needed to be held during the traversal + * of the channels list as it's done synchronously with the only writer. + */ +static void qcom_channel_state_worker(struct work_struct *work) +{ + struct qcom_smd_channel *channel; + struct qcom_smd_edge *edge = container_of(work, + struct qcom_smd_edge, + work); + unsigned remote_state; + + /* + * Rescan smem if we have reason to belive that there are new channels. + */ + if (edge->need_rescan) { + edge->need_rescan = false; + qcom_discover_channels(edge); + } + + /* + * Register a device for any closed channel where the remote processor + * is showing interest in opening the channel. + */ + list_for_each_entry(channel, &edge->channels, list) { + if (channel->state != SMD_CHANNEL_CLOSED) + continue; + + remote_state = GET_RX_CHANNEL_INFO(channel, state); + if (remote_state != SMD_CHANNEL_OPENING && + remote_state != SMD_CHANNEL_OPENED) + continue; + + qcom_smd_create_device(channel); + } + + /* + * Unregister the device for any channel that is opened where the + * remote processor is closing the channel. + */ + list_for_each_entry(channel, &edge->channels, list) { + if (channel->state != SMD_CHANNEL_OPENING && + channel->state != SMD_CHANNEL_OPENED) + continue; + + remote_state = GET_RX_CHANNEL_INFO(channel, state); + if (remote_state == SMD_CHANNEL_OPENING || + remote_state == SMD_CHANNEL_OPENED) + continue; + + qcom_smd_destroy_device(channel); + } +} + +/* + * Parses an of_node describing an edge. + */ +static int qcom_smd_parse_edge(struct device *dev, + struct device_node *node, + struct qcom_smd_edge *edge) +{ + struct device_node *syscon_np; + const char *key; + int irq; + int ret; + + INIT_LIST_HEAD(&edge->channels); + spin_lock_init(&edge->channels_lock); + + INIT_WORK(&edge->work, qcom_channel_state_worker); + + edge->of_node = of_node_get(node); + + irq = irq_of_parse_and_map(node, 0); + if (irq < 0) { + dev_err(dev, "required smd interrupt missing\n"); + return -EINVAL; + } + + ret = devm_request_irq(dev, irq, + qcom_smd_edge_intr, IRQF_TRIGGER_RISING, + node->name, edge); + if (ret) { + dev_err(dev, "failed to request smd irq\n"); + return ret; + } + + edge->irq = irq; + + key = "qcom,smd-edge"; + ret = of_property_read_u32(node, key, &edge->edge_id); + if (ret) { + dev_err(dev, "edge missing %s property\n", key); + return -EINVAL; + } + + syscon_np = of_parse_phandle(node, "qcom,ipc", 0); + if (!syscon_np) { + dev_err(dev, "no qcom,ipc node\n"); + return -ENODEV; + } + + edge->ipc_regmap = syscon_node_to_regmap(syscon_np); + if (IS_ERR(edge->ipc_regmap)) + return PTR_ERR(edge->ipc_regmap); + + key = "qcom,ipc"; + ret = of_property_read_u32_index(node, key, 1, &edge->ipc_offset); + if (ret < 0) { + dev_err(dev, "no offset in %s\n", key); + return -EINVAL; + } + + ret = of_property_read_u32_index(node, key, 2, &edge->ipc_bit); + if (ret < 0) { + dev_err(dev, "no bit in %s\n", key); + return -EINVAL; + } + + return 0; +} + +static int qcom_smd_probe(struct platform_device *pdev) +{ + struct qcom_smd_edge *edge; + struct device_node *node; + struct qcom_smd *smd; + size_t array_size; + int num_edges; + int ret; + int i = 0; + + /* Wait for smem */ + ret = qcom_smem_get(QCOM_SMEM_HOST_ANY, smem_items[0].alloc_tbl_id, NULL, NULL); + if (ret == -EPROBE_DEFER) + return ret; + + num_edges = of_get_available_child_count(pdev->dev.of_node); + array_size = sizeof(*smd) + num_edges * sizeof(struct qcom_smd_edge); + smd = devm_kzalloc(&pdev->dev, array_size, GFP_KERNEL); + if (!smd) + return -ENOMEM; + smd->dev = &pdev->dev; + + smd->num_edges = num_edges; + for_each_available_child_of_node(pdev->dev.of_node, node) { + edge = &smd->edges[i++]; + edge->smd = smd; + + ret = qcom_smd_parse_edge(&pdev->dev, node, edge); + if (ret) + continue; + + edge->need_rescan = true; + schedule_work(&edge->work); + } + + platform_set_drvdata(pdev, smd); + + return 0; +} + +/* + * Shut down all smd clients by making sure that each edge stops processing + * events and scanning for new channels, then call destroy on the devices. + */ +static int qcom_smd_remove(struct platform_device *pdev) +{ + struct qcom_smd_channel *channel; + struct qcom_smd_edge *edge; + struct qcom_smd *smd = platform_get_drvdata(pdev); + int i; + + for (i = 0; i < smd->num_edges; i++) { + edge = &smd->edges[i]; + + disable_irq(edge->irq); + cancel_work_sync(&edge->work); + + list_for_each_entry(channel, &edge->channels, list) { + if (!channel->qsdev) + continue; + + qcom_smd_destroy_device(channel); + } + } + + return 0; +} + +static const struct of_device_id qcom_smd_of_match[] = { + { .compatible = "qcom,smd" }, + {} +}; +MODULE_DEVICE_TABLE(of, qcom_smd_of_match); + +static struct platform_driver qcom_smd_driver = { + .probe = qcom_smd_probe, + .remove = qcom_smd_remove, + .driver = { + .name = "qcom-smd", + .of_match_table = qcom_smd_of_match, + }, +}; + +static int __init qcom_smd_init(void) +{ + int ret; + + ret = bus_register(&qcom_smd_bus); + if (ret) { + pr_err("failed to register smd bus: %d\n", ret); + return ret; + } + + return platform_driver_register(&qcom_smd_driver); +} +postcore_initcall(qcom_smd_init); + +static void __exit qcom_smd_exit(void) +{ + platform_driver_unregister(&qcom_smd_driver); + bus_unregister(&qcom_smd_bus); +} +module_exit(qcom_smd_exit); + +MODULE_AUTHOR("Bjorn Andersson <bjorn.andersson@sonymobile.com>"); +MODULE_DESCRIPTION("Qualcomm Shared Memory Driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/soc/qcom/smem.c b/drivers/soc/qcom/smem.c new file mode 100644 index 000000000000..7c2c324c4b10 --- /dev/null +++ b/drivers/soc/qcom/smem.c @@ -0,0 +1,775 @@ +/* + * Copyright (c) 2015, Sony Mobile Communications AB. + * Copyright (c) 2012-2013, The Linux Foundation. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 and + * only version 2 as published by the Free Software Foundation. + * + * 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. + */ + +#include <linux/hwspinlock.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/soc/qcom/smem.h> + +/* + * The Qualcomm shared memory system is a allocate only heap structure that + * consists of one of more memory areas that can be accessed by the processors + * in the SoC. + * + * All systems contains a global heap, accessible by all processors in the SoC, + * with a table of contents data structure (@smem_header) at the beginning of + * the main shared memory block. + * + * The global header contains meta data for allocations as well as a fixed list + * of 512 entries (@smem_global_entry) that can be initialized to reference + * parts of the shared memory space. + * + * + * In addition to this global heap a set of "private" heaps can be set up at + * boot time with access restrictions so that only certain processor pairs can + * access the data. + * + * These partitions are referenced from an optional partition table + * (@smem_ptable), that is found 4kB from the end of the main smem region. The + * partition table entries (@smem_ptable_entry) lists the involved processors + * (or hosts) and their location in the main shared memory region. + * + * Each partition starts with a header (@smem_partition_header) that identifies + * the partition and holds properties for the two internal memory regions. The + * two regions are cached and non-cached memory respectively. Each region + * contain a link list of allocation headers (@smem_private_entry) followed by + * their data. + * + * Items in the non-cached region are allocated from the start of the partition + * while items in the cached region are allocated from the end. The free area + * is hence the region between the cached and non-cached offsets. + * + * + * To synchronize allocations in the shared memory heaps a remote spinlock must + * be held - currently lock number 3 of the sfpb or tcsr is used for this on all + * platforms. + * + */ + +/* + * Item 3 of the global heap contains an array of versions for the various + * software components in the SoC. We verify that the boot loader version is + * what the expected version (SMEM_EXPECTED_VERSION) as a sanity check. + */ +#define SMEM_ITEM_VERSION 3 +#define SMEM_MASTER_SBL_VERSION_INDEX 7 +#define SMEM_EXPECTED_VERSION 11 + +/* + * The first 8 items are only to be allocated by the boot loader while + * initializing the heap. + */ +#define SMEM_ITEM_LAST_FIXED 8 + +/* Highest accepted item number, for both global and private heaps */ +#define SMEM_ITEM_COUNT 512 + +/* Processor/host identifier for the application processor */ +#define SMEM_HOST_APPS 0 + +/* Max number of processors/hosts in a system */ +#define SMEM_HOST_COUNT 9 + +/** + * struct smem_proc_comm - proc_comm communication struct (legacy) + * @command: current command to be executed + * @status: status of the currently requested command + * @params: parameters to the command + */ +struct smem_proc_comm { + u32 command; + u32 status; + u32 params[2]; +}; + +/** + * struct smem_global_entry - entry to reference smem items on the heap + * @allocated: boolean to indicate if this entry is used + * @offset: offset to the allocated space + * @size: size of the allocated space, 8 byte aligned + * @aux_base: base address for the memory region used by this unit, or 0 for + * the default region. bits 0,1 are reserved + */ +struct smem_global_entry { + u32 allocated; + u32 offset; + u32 size; + u32 aux_base; /* bits 1:0 reserved */ +}; +#define AUX_BASE_MASK 0xfffffffc + +/** + * struct smem_header - header found in beginning of primary smem region + * @proc_comm: proc_comm communication interface (legacy) + * @version: array of versions for the various subsystems + * @initialized: boolean to indicate that smem is initialized + * @free_offset: index of the first unallocated byte in smem + * @available: number of bytes available for allocation + * @reserved: reserved field, must be 0 + * toc: array of references to items + */ +struct smem_header { + struct smem_proc_comm proc_comm[4]; + u32 version[32]; + u32 initialized; + u32 free_offset; + u32 available; + u32 reserved; + struct smem_global_entry toc[SMEM_ITEM_COUNT]; +}; + +/** + * struct smem_ptable_entry - one entry in the @smem_ptable list + * @offset: offset, within the main shared memory region, of the partition + * @size: size of the partition + * @flags: flags for the partition (currently unused) + * @host0: first processor/host with access to this partition + * @host1: second processor/host with access to this partition + * @reserved: reserved entries for later use + */ +struct smem_ptable_entry { + u32 offset; + u32 size; + u32 flags; + u16 host0; + u16 host1; + u32 reserved[8]; +}; + +/** + * struct smem_ptable - partition table for the private partitions + * @magic: magic number, must be SMEM_PTABLE_MAGIC + * @version: version of the partition table + * @num_entries: number of partitions in the table + * @reserved: for now reserved entries + * @entry: list of @smem_ptable_entry for the @num_entries partitions + */ +struct smem_ptable { + u32 magic; + u32 version; + u32 num_entries; + u32 reserved[5]; + struct smem_ptable_entry entry[]; +}; +#define SMEM_PTABLE_MAGIC 0x434f5424 /* "$TOC" */ + +/** + * struct smem_partition_header - header of the partitions + * @magic: magic number, must be SMEM_PART_MAGIC + * @host0: first processor/host with access to this partition + * @host1: second processor/host with access to this partition + * @size: size of the partition + * @offset_free_uncached: offset to the first free byte of uncached memory in + * this partition + * @offset_free_cached: offset to the first free byte of cached memory in this + * partition + * @reserved: for now reserved entries + */ +struct smem_partition_header { + u32 magic; + u16 host0; + u16 host1; + u32 size; + u32 offset_free_uncached; + u32 offset_free_cached; + u32 reserved[3]; +}; +#define SMEM_PART_MAGIC 0x54525024 /* "$PRT" */ + +/** + * struct smem_private_entry - header of each item in the private partition + * @canary: magic number, must be SMEM_PRIVATE_CANARY + * @item: identifying number of the smem item + * @size: size of the data, including padding bytes + * @padding_data: number of bytes of padding of data + * @padding_hdr: number of bytes of padding between the header and the data + * @reserved: for now reserved entry + */ +struct smem_private_entry { + u16 canary; + u16 item; + u32 size; /* includes padding bytes */ + u16 padding_data; + u16 padding_hdr; + u32 reserved; +}; +#define SMEM_PRIVATE_CANARY 0xa5a5 + +/** + * struct smem_region - representation of a chunk of memory used for smem + * @aux_base: identifier of aux_mem base + * @virt_base: virtual base address of memory with this aux_mem identifier + * @size: size of the memory region + */ +struct smem_region { + u32 aux_base; + void __iomem *virt_base; + size_t size; +}; + +/** + * struct qcom_smem - device data for the smem device + * @dev: device pointer + * @hwlock: reference to a hwspinlock + * @partitions: list of pointers to partitions affecting the current + * processor/host + * @num_regions: number of @regions + * @regions: list of the memory regions defining the shared memory + */ +struct qcom_smem { + struct device *dev; + + struct hwspinlock *hwlock; + + struct smem_partition_header *partitions[SMEM_HOST_COUNT]; + + unsigned num_regions; + struct smem_region regions[0]; +}; + +/* Pointer to the one and only smem handle */ +static struct qcom_smem *__smem; + +/* Timeout (ms) for the trylock of remote spinlocks */ +#define HWSPINLOCK_TIMEOUT 1000 + +static int qcom_smem_alloc_private(struct qcom_smem *smem, + unsigned host, + unsigned item, + size_t size) +{ + struct smem_partition_header *phdr; + struct smem_private_entry *hdr; + size_t alloc_size; + void *p; + + /* We're not going to find it if there's no matching partition */ + if (host >= SMEM_HOST_COUNT || !smem->partitions[host]) + return -ENOENT; + + phdr = smem->partitions[host]; + + p = (void *)phdr + sizeof(*phdr); + while (p < (void *)phdr + phdr->offset_free_uncached) { + hdr = p; + + if (hdr->canary != SMEM_PRIVATE_CANARY) { + dev_err(smem->dev, + "Found invalid canary in host %d partition\n", + host); + return -EINVAL; + } + + if (hdr->item == item) + return -EEXIST; + + p += sizeof(*hdr) + hdr->padding_hdr + hdr->size; + } + + /* Check that we don't grow into the cached region */ + alloc_size = sizeof(*hdr) + ALIGN(size, 8); + if (p + alloc_size >= (void *)phdr + phdr->offset_free_cached) { + dev_err(smem->dev, "Out of memory\n"); + return -ENOSPC; + } + + hdr = p; + hdr->canary = SMEM_PRIVATE_CANARY; + hdr->item = item; + hdr->size = ALIGN(size, 8); + hdr->padding_data = hdr->size - size; + hdr->padding_hdr = 0; + + /* + * Ensure the header is written before we advance the free offset, so + * that remote processors that does not take the remote spinlock still + * gets a consistent view of the linked list. + */ + wmb(); + phdr->offset_free_uncached += alloc_size; + + return 0; +} + +static int qcom_smem_alloc_global(struct qcom_smem *smem, + unsigned item, + size_t size) +{ + struct smem_header *header; + struct smem_global_entry *entry; + + if (WARN_ON(item >= SMEM_ITEM_COUNT)) + return -EINVAL; + + header = smem->regions[0].virt_base; + entry = &header->toc[item]; + if (entry->allocated) + return -EEXIST; + + size = ALIGN(size, 8); + if (WARN_ON(size > header->available)) + return -ENOMEM; + + entry->offset = header->free_offset; + entry->size = size; + + /* + * Ensure the header is consistent before we mark the item allocated, + * so that remote processors will get a consistent view of the item + * even though they do not take the spinlock on read. + */ + wmb(); + entry->allocated = 1; + + header->free_offset += size; + header->available -= size; + + return 0; +} + +/** + * qcom_smem_alloc() - allocate space for a smem item + * @host: remote processor id, or -1 + * @item: smem item handle + * @size: number of bytes to be allocated + * + * Allocate space for a given smem item of size @size, given that the item is + * not yet allocated. + */ +int qcom_smem_alloc(unsigned host, unsigned item, size_t size) +{ + unsigned long flags; + int ret; + + if (!__smem) + return -EPROBE_DEFER; + + if (item < SMEM_ITEM_LAST_FIXED) { + dev_err(__smem->dev, + "Rejecting allocation of static entry %d\n", item); + return -EINVAL; + } + + ret = hwspin_lock_timeout_irqsave(__smem->hwlock, + HWSPINLOCK_TIMEOUT, + &flags); + if (ret) + return ret; + + ret = qcom_smem_alloc_private(__smem, host, item, size); + if (ret == -ENOENT) + ret = qcom_smem_alloc_global(__smem, item, size); + + hwspin_unlock_irqrestore(__smem->hwlock, &flags); + + return ret; +} +EXPORT_SYMBOL(qcom_smem_alloc); + +static int qcom_smem_get_global(struct qcom_smem *smem, + unsigned item, + void **ptr, + size_t *size) +{ + struct smem_header *header; + struct smem_region *area; + struct smem_global_entry *entry; + u32 aux_base; + unsigned i; + + if (WARN_ON(item >= SMEM_ITEM_COUNT)) + return -EINVAL; + + header = smem->regions[0].virt_base; + entry = &header->toc[item]; + if (!entry->allocated) + return -ENXIO; + + if (ptr != NULL) { + aux_base = entry->aux_base & AUX_BASE_MASK; + + for (i = 0; i < smem->num_regions; i++) { + area = &smem->regions[i]; + + if (area->aux_base == aux_base || !aux_base) { + *ptr = area->virt_base + entry->offset; + break; + } + } + } + if (size != NULL) + *size = entry->size; + + return 0; +} + +static int qcom_smem_get_private(struct qcom_smem *smem, + unsigned host, + unsigned item, + void **ptr, + size_t *size) +{ + struct smem_partition_header *phdr; + struct smem_private_entry *hdr; + void *p; + + /* We're not going to find it if there's no matching partition */ + if (host >= SMEM_HOST_COUNT || !smem->partitions[host]) + return -ENOENT; + + phdr = smem->partitions[host]; + + p = (void *)phdr + sizeof(*phdr); + while (p < (void *)phdr + phdr->offset_free_uncached) { + hdr = p; + + if (hdr->canary != SMEM_PRIVATE_CANARY) { + dev_err(smem->dev, + "Found invalid canary in host %d partition\n", + host); + return -EINVAL; + } + + if (hdr->item == item) { + if (ptr != NULL) + *ptr = p + sizeof(*hdr) + hdr->padding_hdr; + + if (size != NULL) + *size = hdr->size - hdr->padding_data; + + return 0; + } + + p += sizeof(*hdr) + hdr->padding_hdr + hdr->size; + } + + return -ENOENT; +} + +/** + * qcom_smem_get() - resolve ptr of size of a smem item + * @host: the remote processor, or -1 + * @item: smem item handle + * @ptr: pointer to be filled out with address of the item + * @size: pointer to be filled out with size of the item + * + * Looks up pointer and size of a smem item. + */ +int qcom_smem_get(unsigned host, unsigned item, void **ptr, size_t *size) +{ + unsigned long flags; + int ret; + + if (!__smem) + return -EPROBE_DEFER; + + ret = hwspin_lock_timeout_irqsave(__smem->hwlock, + HWSPINLOCK_TIMEOUT, + &flags); + if (ret) + return ret; + + ret = qcom_smem_get_private(__smem, host, item, ptr, size); + if (ret == -ENOENT) + ret = qcom_smem_get_global(__smem, item, ptr, size); + + hwspin_unlock_irqrestore(__smem->hwlock, &flags); + return ret; + +} +EXPORT_SYMBOL(qcom_smem_get); + +/** + * qcom_smem_get_free_space() - retrieve amount of free space in a partition + * @host: the remote processor identifying a partition, or -1 + * + * To be used by smem clients as a quick way to determine if any new + * allocations has been made. + */ +int qcom_smem_get_free_space(unsigned host) +{ + struct smem_partition_header *phdr; + struct smem_header *header; + unsigned ret; + + if (!__smem) + return -EPROBE_DEFER; + + if (host < SMEM_HOST_COUNT && __smem->partitions[host]) { + phdr = __smem->partitions[host]; + ret = phdr->offset_free_cached - phdr->offset_free_uncached; + } else { + header = __smem->regions[0].virt_base; + ret = header->available; + } + + return ret; +} +EXPORT_SYMBOL(qcom_smem_get_free_space); + +static int qcom_smem_get_sbl_version(struct qcom_smem *smem) +{ + unsigned *versions; + size_t size; + int ret; + + ret = qcom_smem_get_global(smem, SMEM_ITEM_VERSION, + (void **)&versions, &size); + if (ret < 0) { + dev_err(smem->dev, "Unable to read the version item\n"); + return -ENOENT; + } + + if (size < sizeof(unsigned) * SMEM_MASTER_SBL_VERSION_INDEX) { + dev_err(smem->dev, "Version item is too small\n"); + return -EINVAL; + } + + return versions[SMEM_MASTER_SBL_VERSION_INDEX]; +} + +static int qcom_smem_enumerate_partitions(struct qcom_smem *smem, + unsigned local_host) +{ + struct smem_partition_header *header; + struct smem_ptable_entry *entry; + struct smem_ptable *ptable; + unsigned remote_host; + int i; + + ptable = smem->regions[0].virt_base + smem->regions[0].size - SZ_4K; + if (ptable->magic != SMEM_PTABLE_MAGIC) + return 0; + + if (ptable->version != 1) { + dev_err(smem->dev, + "Unsupported partition header version %d\n", + ptable->version); + return -EINVAL; + } + + for (i = 0; i < ptable->num_entries; i++) { + entry = &ptable->entry[i]; + + if (entry->host0 != local_host && entry->host1 != local_host) + continue; + + if (!entry->offset) + continue; + + if (!entry->size) + continue; + + if (entry->host0 == local_host) + remote_host = entry->host1; + else + remote_host = entry->host0; + + if (remote_host >= SMEM_HOST_COUNT) { + dev_err(smem->dev, + "Invalid remote host %d\n", + remote_host); + return -EINVAL; + } + + if (smem->partitions[remote_host]) { + dev_err(smem->dev, + "Already found a partition for host %d\n", + remote_host); + return -EINVAL; + } + + header = smem->regions[0].virt_base + entry->offset; + + if (header->magic != SMEM_PART_MAGIC) { + dev_err(smem->dev, + "Partition %d has invalid magic\n", i); + return -EINVAL; + } + + if (header->host0 != local_host && header->host1 != local_host) { + dev_err(smem->dev, + "Partition %d hosts are invalid\n", i); + return -EINVAL; + } + + if (header->host0 != remote_host && header->host1 != remote_host) { + dev_err(smem->dev, + "Partition %d hosts are invalid\n", i); + return -EINVAL; + } + + if (header->size != entry->size) { + dev_err(smem->dev, + "Partition %d has invalid size\n", i); + return -EINVAL; + } + + if (header->offset_free_uncached > header->size) { + dev_err(smem->dev, + "Partition %d has invalid free pointer\n", i); + return -EINVAL; + } + + smem->partitions[remote_host] = header; + } + + return 0; +} + +static int qcom_smem_count_mem_regions(struct platform_device *pdev) +{ + struct resource *res; + int num_regions = 0; + int i; + + for (i = 0; i < pdev->num_resources; i++) { + res = &pdev->resource[i]; + + if (resource_type(res) == IORESOURCE_MEM) + num_regions++; + } + + return num_regions; +} + +static int qcom_smem_probe(struct platform_device *pdev) +{ + struct smem_header *header; + struct device_node *np; + struct qcom_smem *smem; + struct resource *res; + struct resource r; + size_t array_size; + int num_regions = 0; + int hwlock_id; + u32 version; + int ret; + int i; + + num_regions = qcom_smem_count_mem_regions(pdev) + 1; + + array_size = num_regions * sizeof(struct smem_region); + smem = devm_kzalloc(&pdev->dev, sizeof(*smem) + array_size, GFP_KERNEL); + if (!smem) + return -ENOMEM; + + smem->dev = &pdev->dev; + smem->num_regions = num_regions; + + np = of_parse_phandle(pdev->dev.of_node, "memory-region", 0); + if (!np) { + dev_err(&pdev->dev, "No memory-region specified\n"); + return -EINVAL; + } + + ret = of_address_to_resource(np, 0, &r); + of_node_put(np); + if (ret) + return ret; + + smem->regions[0].aux_base = (u32)r.start; + smem->regions[0].size = resource_size(&r); + smem->regions[0].virt_base = devm_ioremap_nocache(&pdev->dev, + r.start, + resource_size(&r)); + if (!smem->regions[0].virt_base) + return -ENOMEM; + + for (i = 1; i < num_regions; i++) { + res = platform_get_resource(pdev, IORESOURCE_MEM, i - 1); + + smem->regions[i].aux_base = (u32)res->start; + smem->regions[i].size = resource_size(res); + smem->regions[i].virt_base = devm_ioremap_nocache(&pdev->dev, + res->start, + resource_size(res)); + if (!smem->regions[i].virt_base) + return -ENOMEM; + } + + header = smem->regions[0].virt_base; + if (header->initialized != 1 || header->reserved) { + dev_err(&pdev->dev, "SMEM is not initialized by SBL\n"); + return -EINVAL; + } + + version = qcom_smem_get_sbl_version(smem); + if (version >> 16 != SMEM_EXPECTED_VERSION) { + dev_err(&pdev->dev, "Unsupported SMEM version 0x%x\n", version); + return -EINVAL; + } + + ret = qcom_smem_enumerate_partitions(smem, SMEM_HOST_APPS); + if (ret < 0) + return ret; + + hwlock_id = of_hwspin_lock_get_id(pdev->dev.of_node, 0); + if (hwlock_id < 0) { + dev_err(&pdev->dev, "failed to retrieve hwlock\n"); + return hwlock_id; + } + + smem->hwlock = hwspin_lock_request_specific(hwlock_id); + if (!smem->hwlock) + return -ENXIO; + + __smem = smem; + + return 0; +} + +static int qcom_smem_remove(struct platform_device *pdev) +{ + __smem = NULL; + hwspin_lock_free(__smem->hwlock); + + return 0; +} + +static const struct of_device_id qcom_smem_of_match[] = { + { .compatible = "qcom,smem" }, + {} +}; +MODULE_DEVICE_TABLE(of, qcom_smem_of_match); + +static struct platform_driver qcom_smem_driver = { + .probe = qcom_smem_probe, + .remove = qcom_smem_remove, + .driver = { + .name = "qcom-smem", + .of_match_table = qcom_smem_of_match, + .suppress_bind_attrs = true, + }, +}; + +static int __init qcom_smem_init(void) +{ + return platform_driver_register(&qcom_smem_driver); +} +arch_initcall(qcom_smem_init); + +static void __exit qcom_smem_exit(void) +{ + platform_driver_unregister(&qcom_smem_driver); +} +module_exit(qcom_smem_exit) + +MODULE_AUTHOR("Bjorn Andersson <bjorn.andersson@sonymobile.com>"); +MODULE_DESCRIPTION("Qualcomm Shared Memory Manager"); +MODULE_LICENSE("GPL v2"); |