soc: qcom: smp2p: Qualcomm Shared Memory Point to Point (50e99641) · Commits · e / devices / android_kernel_teracube_2e

drivers/soc/qcom/Kconfig

+8 −0

Original line number	Diff line number	Diff line
		@@ -53,6 +53,14 @@ config QCOM_SMD_RPM
		config QCOM_SMEM_STATE
		bool

		config QCOM_SMP2P
		bool "Qualcomm Shared Memory Point to Point support"
		depends on QCOM_SMEM
		select QCOM_SMEM_STATE
		help
		Say yes here to support the Qualcomm Shared Memory Point to Point
		protocol.

		config QCOM_SMSM
		bool "Qualcomm Shared Memory State Machine"
		depends on QCOM_SMEM

drivers/soc/qcom/Makefile

+1 −0

Original line number	Diff line number	Diff line
		@@ -4,4 +4,5 @@ obj-$(CONFIG_QCOM_SMD) += smd.o
		obj-$(CONFIG_QCOM_SMD_RPM) += smd-rpm.o
		obj-$(CONFIG_QCOM_SMEM) += smem.o
		obj-$(CONFIG_QCOM_SMEM_STATE) += smem_state.o
		obj-$(CONFIG_QCOM_SMP2P) += smp2p.o
		obj-$(CONFIG_QCOM_SMSM) += smsm.o

drivers/soc/qcom/smp2p.c

0 → 100644

+578 −0

Original line number	Diff line number	Diff line
		/*
		* 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/list.h>
		#include <linux/io.h>
		#include <linux/of.h>
		#include <linux/irq.h>
		#include <linux/irqdomain.h>
		#include <linux/mfd/syscon.h>
		#include <linux/module.h>
		#include <linux/platform_device.h>
		#include <linux/regmap.h>
		#include <linux/soc/qcom/smem.h>
		#include <linux/soc/qcom/smem_state.h>
		#include <linux/spinlock.h>

		/*
		* The Shared Memory Point to Point (SMP2P) protocol facilitates communication
		* of a single 32-bit value between two processors. Each value has a single
		* writer (the local side) and a single reader (the remote side). Values are
		* uniquely identified in the system by the directed edge (local processor ID
		* to remote processor ID) and a string identifier.
		*
		* Each processor is responsible for creating the outgoing SMEM items and each
		* item is writable by the local processor and readable by the remote
		* processor. By using two separate SMEM items that are single-reader and
		* single-writer, SMP2P does not require any remote locking mechanisms.
		*
		* The driver uses the Linux GPIO and interrupt framework to expose a virtual
		* GPIO for each outbound entry and a virtual interrupt controller for each
		* inbound entry.
		*/

		#define SMP2P_MAX_ENTRY 16
		#define SMP2P_MAX_ENTRY_NAME 16

		#define SMP2P_FEATURE_SSR_ACK 0x1

		#define SMP2P_MAGIC 0x504d5324

		/**
		* struct smp2p_smem_item - in memory communication structure
		* @magic: magic number
		* @version: version - must be 1
		* @features: features flag - currently unused
		* @local_pid: processor id of sending end
		* @remote_pid: processor id of receiving end
		* @total_entries: number of entries - always SMP2P_MAX_ENTRY
		* @valid_entries: number of allocated entries
		* @flags:
		* @entries: individual communication entries
		* @name: name of the entry
		* @value: content of the entry
		*/
		struct smp2p_smem_item {
		u32 magic;
		u8 version;
		unsigned features:24;
		u16 local_pid;
		u16 remote_pid;
		u16 total_entries;
		u16 valid_entries;
		u32 flags;

		struct {
		u8 name[SMP2P_MAX_ENTRY_NAME];
		u32 value;
		} entries[SMP2P_MAX_ENTRY];
		} __packed;

		/**
		* struct smp2p_entry - driver context matching one entry
		* @node: list entry to keep track of allocated entries
		* @smp2p: reference to the device driver context
		* @name: name of the entry, to match against smp2p_smem_item
		* @value: pointer to smp2p_smem_item entry value
		* @last_value: last handled value
		* @domain: irq_domain for inbound entries
		* @irq_enabled:bitmap to track enabled irq bits
		* @irq_rising: bitmap to mark irq bits for rising detection
		* @irq_falling:bitmap to mark irq bits for falling detection
		* @state: smem state handle
		* @lock: spinlock to protect read-modify-write of the value
		*/
		struct smp2p_entry {
		struct list_head node;
		struct qcom_smp2p *smp2p;

		const char *name;
		u32 *value;
		u32 last_value;

		struct irq_domain *domain;
		DECLARE_BITMAP(irq_enabled, 32);
		DECLARE_BITMAP(irq_rising, 32);
		DECLARE_BITMAP(irq_falling, 32);

		struct qcom_smem_state *state;

		spinlock_t lock;
		};

		#define SMP2P_INBOUND 0
		#define SMP2P_OUTBOUND 1

		/**
		* struct qcom_smp2p - device driver context
		* @dev: device driver handle
		* @in: pointer to the inbound smem item
		* @smem_items: ids of the two smem items
		* @valid_entries: already scanned inbound entries
		* @local_pid: processor id of the inbound edge
		* @remote_pid: processor id of the outbound edge
		* @ipc_regmap: regmap for the outbound ipc
		* @ipc_offset: offset within the regmap
		* @ipc_bit: bit in regmap@offset to kick to signal remote processor
		* @inbound: list of inbound entries
		* @outbound: list of outbound entries
		*/
		struct qcom_smp2p {
		struct device *dev;

		struct smp2p_smem_item *in;
		struct smp2p_smem_item *out;

		unsigned smem_items[SMP2P_OUTBOUND + 1];

		unsigned valid_entries;

		unsigned local_pid;
		unsigned remote_pid;

		struct regmap *ipc_regmap;
		int ipc_offset;
		int ipc_bit;

		struct list_head inbound;
		struct list_head outbound;
		};

		static void qcom_smp2p_kick(struct qcom_smp2p *smp2p)
		{
		/* Make sure any updated data is written before the kick */
		wmb();
		regmap_write(smp2p->ipc_regmap, smp2p->ipc_offset, BIT(smp2p->ipc_bit));
		}

		/**
		* qcom_smp2p_intr() - interrupt handler for incoming notifications
		* @irq: unused
		* @data: smp2p driver context
		*
		* Handle notifications from the remote side to handle newly allocated entries
		* or any changes to the state bits of existing entries.
		*/
		static irqreturn_t qcom_smp2p_intr(int irq, void *data)
		{
		struct smp2p_smem_item *in;
		struct smp2p_entry *entry;
		struct qcom_smp2p *smp2p = data;
		unsigned smem_id = smp2p->smem_items[SMP2P_INBOUND];
		unsigned pid = smp2p->remote_pid;
		size_t size;
		int irq_pin;
		u32 status;
		char buf[SMP2P_MAX_ENTRY_NAME];
		u32 val;
		int i;

		in = smp2p->in;

		/* Acquire smem item, if not already found */
		if (!in) {
		in = qcom_smem_get(pid, smem_id, &size);
		if (IS_ERR(in)) {
		dev_err(smp2p->dev,
		"Unable to acquire remote smp2p item\n");
		return IRQ_HANDLED;
		}

		smp2p->in = in;
		}

		/* Match newly created entries */
		for (i = smp2p->valid_entries; i < in->valid_entries; i++) {
		list_for_each_entry(entry, &smp2p->inbound, node) {
		memcpy_fromio(buf, in->entries[i].name, sizeof(buf));
		if (!strcmp(buf, entry->name)) {
		entry->value = &in->entries[i].value;
		break;
		}
		}
		}
		smp2p->valid_entries = i;

		/* Fire interrupts based on any value changes */
		list_for_each_entry(entry, &smp2p->inbound, node) {
		/* Ignore entries not yet allocated by the remote side */
		if (!entry->value)
		continue;

		val = readl(entry->value);

		status = val ^ entry->last_value;
		entry->last_value = val;

		/* No changes of this entry? */
		if (!status)
		continue;

		for_each_set_bit(i, entry->irq_enabled, 32) {
		if (!(status & BIT(i)))
		continue;

		if ((val & BIT(i) && test_bit(i, entry->irq_rising)) \|\|
		(!(val & BIT(i)) && test_bit(i, entry->irq_falling))) {
		irq_pin = irq_find_mapping(entry->domain, i);
		handle_nested_irq(irq_pin);
		}
		}
		}

		return IRQ_HANDLED;
		}

		static void smp2p_mask_irq(struct irq_data *irqd)
		{
		struct smp2p_entry *entry = irq_data_get_irq_chip_data(irqd);
		irq_hw_number_t irq = irqd_to_hwirq(irqd);

		clear_bit(irq, entry->irq_enabled);
		}

		static void smp2p_unmask_irq(struct irq_data *irqd)
		{
		struct smp2p_entry *entry = irq_data_get_irq_chip_data(irqd);
		irq_hw_number_t irq = irqd_to_hwirq(irqd);

		set_bit(irq, entry->irq_enabled);
		}

		static int smp2p_set_irq_type(struct irq_data *irqd, unsigned int type)
		{
		struct smp2p_entry *entry = irq_data_get_irq_chip_data(irqd);
		irq_hw_number_t irq = irqd_to_hwirq(irqd);

		if (!(type & IRQ_TYPE_EDGE_BOTH))
		return -EINVAL;

		if (type & IRQ_TYPE_EDGE_RISING)
		set_bit(irq, entry->irq_rising);
		else
		clear_bit(irq, entry->irq_rising);

		if (type & IRQ_TYPE_EDGE_FALLING)
		set_bit(irq, entry->irq_falling);
		else
		clear_bit(irq, entry->irq_falling);

		return 0;
		}

		static struct irq_chip smp2p_irq_chip = {
		.name = "smp2p",
		.irq_mask = smp2p_mask_irq,
		.irq_unmask = smp2p_unmask_irq,
		.irq_set_type = smp2p_set_irq_type,
		};

		static int smp2p_irq_map(struct irq_domain *d,
		unsigned int irq,
		irq_hw_number_t hw)
		{
		struct smp2p_entry *entry = d->host_data;

		irq_set_chip_and_handler(irq, &smp2p_irq_chip, handle_level_irq);
		irq_set_chip_data(irq, entry);
		irq_set_nested_thread(irq, 1);
		irq_set_noprobe(irq);

		return 0;
		}

		static const struct irq_domain_ops smp2p_irq_ops = {
		.map = smp2p_irq_map,
		.xlate = irq_domain_xlate_twocell,
		};

		static int qcom_smp2p_inbound_entry(struct qcom_smp2p *smp2p,
		struct smp2p_entry *entry,
		struct device_node *node)
		{
		entry->domain = irq_domain_add_linear(node, 32, &smp2p_irq_ops, entry);
		if (!entry->domain) {
		dev_err(smp2p->dev, "failed to add irq_domain\n");
		return -ENOMEM;
		}

		return 0;
		}

		static int smp2p_update_bits(void *data, u32 mask, u32 value)
		{
		struct smp2p_entry *entry = data;
		u32 orig;
		u32 val;

		spin_lock(&entry->lock);
		val = orig = readl(entry->value);
		val &= ~mask;
		val \|= value;
		writel(val, entry->value);
		spin_unlock(&entry->lock);

		if (val != orig)
		qcom_smp2p_kick(entry->smp2p);

		return 0;
		}

		static const struct qcom_smem_state_ops smp2p_state_ops = {
		.update_bits = smp2p_update_bits,
		};

		static int qcom_smp2p_outbound_entry(struct qcom_smp2p *smp2p,
		struct smp2p_entry *entry,
		struct device_node *node)
		{
		struct smp2p_smem_item *out = smp2p->out;
		char buf[SMP2P_MAX_ENTRY_NAME] = {};

		/* Allocate an entry from the smem item */
		strlcpy(buf, entry->name, SMP2P_MAX_ENTRY_NAME);
		memcpy_toio(out->entries[out->valid_entries].name, buf, SMP2P_MAX_ENTRY_NAME);
		out->valid_entries++;

		/* Make the logical entry reference the physical value */
		entry->value = &out->entries[out->valid_entries].value;

		entry->state = qcom_smem_state_register(node, &smp2p_state_ops, entry);
		if (IS_ERR(entry->state)) {
		dev_err(smp2p->dev, "failed to register qcom_smem_state\n");
		return PTR_ERR(entry->state);
		}

		return 0;
		}

		static int qcom_smp2p_alloc_outbound_item(struct qcom_smp2p *smp2p)
		{
		struct smp2p_smem_item *out;
		unsigned smem_id = smp2p->smem_items[SMP2P_OUTBOUND];
		unsigned pid = smp2p->remote_pid;
		int ret;

		ret = qcom_smem_alloc(pid, smem_id, sizeof(*out));
		if (ret < 0 && ret != -EEXIST) {
		if (ret != -EPROBE_DEFER)
		dev_err(smp2p->dev,
		"unable to allocate local smp2p item\n");
		return ret;
		}

		out = qcom_smem_get(pid, smem_id, NULL);
		if (IS_ERR(out)) {
		dev_err(smp2p->dev, "Unable to acquire local smp2p item\n");
		return PTR_ERR(out);
		}

		memset(out, 0, sizeof(*out));
		out->magic = SMP2P_MAGIC;
		out->local_pid = smp2p->local_pid;
		out->remote_pid = smp2p->remote_pid;
		out->total_entries = SMP2P_MAX_ENTRY;
		out->valid_entries = 0;

		/*
		* Make sure the rest of the header is written before we validate the
		* item by writing a valid version number.
		*/
		wmb();
		out->version = 1;

		qcom_smp2p_kick(smp2p);

		smp2p->out = out;

		return 0;
		}

		static int smp2p_parse_ipc(struct qcom_smp2p *smp2p)
		{
		struct device_node *syscon;
		struct device *dev = smp2p->dev;
		const char *key;
		int ret;

		syscon = of_parse_phandle(dev->of_node, "qcom,ipc", 0);
		if (!syscon) {
		dev_err(dev, "no qcom,ipc node\n");
		return -ENODEV;
		}

		smp2p->ipc_regmap = syscon_node_to_regmap(syscon);
		if (IS_ERR(smp2p->ipc_regmap))
		return PTR_ERR(smp2p->ipc_regmap);

		key = "qcom,ipc";
		ret = of_property_read_u32_index(dev->of_node, key, 1, &smp2p->ipc_offset);
		if (ret < 0) {
		dev_err(dev, "no offset in %s\n", key);
		return -EINVAL;
		}

		ret = of_property_read_u32_index(dev->of_node, key, 2, &smp2p->ipc_bit);
		if (ret < 0) {
		dev_err(dev, "no bit in %s\n", key);
		return -EINVAL;
		}

		return 0;
		}

		static int qcom_smp2p_probe(struct platform_device *pdev)
		{
		struct smp2p_entry *entry;
		struct device_node *node;
		struct qcom_smp2p *smp2p;
		const char *key;
		int irq;
		int ret;

		smp2p = devm_kzalloc(&pdev->dev, sizeof(*smp2p), GFP_KERNEL);
		if (!smp2p)
		return -ENOMEM;

		smp2p->dev = &pdev->dev;
		INIT_LIST_HEAD(&smp2p->inbound);
		INIT_LIST_HEAD(&smp2p->outbound);

		platform_set_drvdata(pdev, smp2p);

		ret = smp2p_parse_ipc(smp2p);
		if (ret)
		return ret;

		key = "qcom,smem";
		ret = of_property_read_u32_array(pdev->dev.of_node, key,
		smp2p->smem_items, 2);
		if (ret)
		return ret;

		key = "qcom,local-pid";
		ret = of_property_read_u32(pdev->dev.of_node, key, &smp2p->local_pid);
		if (ret < 0) {
		dev_err(&pdev->dev, "failed to read %s\n", key);
		return -EINVAL;
		}

		key = "qcom,remote-pid";
		ret = of_property_read_u32(pdev->dev.of_node, key, &smp2p->remote_pid);
		if (ret < 0) {
		dev_err(&pdev->dev, "failed to read %s\n", key);
		return -EINVAL;
		}

		irq = platform_get_irq(pdev, 0);
		if (irq < 0) {
		dev_err(&pdev->dev, "unable to acquire smp2p interrupt\n");
		return irq;
		}

		ret = qcom_smp2p_alloc_outbound_item(smp2p);
		if (ret < 0)
		return ret;

		for_each_available_child_of_node(pdev->dev.of_node, node) {
		entry = devm_kzalloc(&pdev->dev, sizeof(*entry), GFP_KERNEL);
		if (!entry) {
		ret = -ENOMEM;
		goto unwind_interfaces;
		}

		entry->smp2p = smp2p;
		spin_lock_init(&entry->lock);

		ret = of_property_read_string(node, "qcom,entry-name", &entry->name);
		if (ret < 0)
		goto unwind_interfaces;

		if (of_property_read_bool(node, "interrupt-controller")) {
		ret = qcom_smp2p_inbound_entry(smp2p, entry, node);
		if (ret < 0)
		goto unwind_interfaces;

		list_add(&entry->node, &smp2p->inbound);
		} else {
		ret = qcom_smp2p_outbound_entry(smp2p, entry, node);
		if (ret < 0)
		goto unwind_interfaces;

		list_add(&entry->node, &smp2p->outbound);
		}
		}

		/* Kick the outgoing edge after allocating entries */
		qcom_smp2p_kick(smp2p);

		ret = devm_request_threaded_irq(&pdev->dev, irq,
		NULL, qcom_smp2p_intr,
		IRQF_ONESHOT,
		"smp2p", (void *)smp2p);
		if (ret) {
		dev_err(&pdev->dev, "failed to request interrupt\n");
		goto unwind_interfaces;
		}


		return 0;

		unwind_interfaces:
		list_for_each_entry(entry, &smp2p->inbound, node)
		irq_domain_remove(entry->domain);

		list_for_each_entry(entry, &smp2p->outbound, node)
		qcom_smem_state_unregister(entry->state);

		smp2p->out->valid_entries = 0;

		return ret;
		}

		static int qcom_smp2p_remove(struct platform_device *pdev)
		{
		struct qcom_smp2p *smp2p = platform_get_drvdata(pdev);
		struct smp2p_entry *entry;

		list_for_each_entry(entry, &smp2p->inbound, node)
		irq_domain_remove(entry->domain);

		list_for_each_entry(entry, &smp2p->outbound, node)
		qcom_smem_state_unregister(entry->state);

		smp2p->out->valid_entries = 0;

		return 0;
		}

		static const struct of_device_id qcom_smp2p_of_match[] = {
		{ .compatible = "qcom,smp2p" },
		{}
		};
		MODULE_DEVICE_TABLE(of, qcom_smp2p_of_match);

		static struct platform_driver qcom_smp2p_driver = {
		.probe = qcom_smp2p_probe,
		.remove = qcom_smp2p_remove,
		.driver = {
		.name = "qcom_smp2p",
		.of_match_table = qcom_smp2p_of_match,
		},
		};
		module_platform_driver(qcom_smp2p_driver);

		MODULE_DESCRIPTION("Qualcomm Shared Memory Point to Point driver");
		MODULE_LICENSE("GPL v2");