remoteproc/keystone: Add a remoteproc driver for Keystone 2 DSPs

	  It's safe to say n here if you're not interested in multimedia

	  offloading.

config KEYSTONE_REMOTEPROC

	tristate "Keystone Remoteproc support"

	depends on ARCH_KEYSTONE

	depends on RESET_CONTROLLER

	depends on REMOTEPROC

	select RPMSG_VIRTIO

	help

	  Say Y here here to support Keystone remote processors (DSP)

	  via the remote processor framework.

	  It's safe to say N here if you're not interested in the Keystone

	  DSPs or just want to use a bare minimum kernel.

config QCOM_ADSP_PIL

	tristate "Qualcomm ADSP Peripheral Image Loader"

	depends on OF && ARCH_QCOM

obj-$(CONFIG_OMAP_REMOTEPROC)		+= omap_remoteproc.o

obj-$(CONFIG_WKUP_M3_RPROC)		+= wkup_m3_rproc.o

obj-$(CONFIG_DA8XX_REMOTEPROC)		+= da8xx_remoteproc.o

obj-$(CONFIG_KEYSTONE_REMOTEPROC)	+= keystone_remoteproc.o

obj-$(CONFIG_QCOM_ADSP_PIL)		+= qcom_adsp_pil.o

obj-$(CONFIG_QCOM_RPROC_COMMON)		+= qcom_common.o

obj-$(CONFIG_QCOM_Q6V5_PIL)		+= qcom_q6v5_pil.o

/*

 * TI Keystone DSP remoteproc driver

 *

 * Copyright (C) 2015-2017 Texas Instruments Incorporated - http://www.ti.com/

 *

 * 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 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/slab.h>

#include <linux/io.h>

#include <linux/interrupt.h>

#include <linux/platform_device.h>

#include <linux/pm_runtime.h>

#include <linux/workqueue.h>

#include <linux/of_address.h>

#include <linux/of_reserved_mem.h>

#include <linux/of_gpio.h>

#include <linux/regmap.h>

#include <linux/mfd/syscon.h>

#include <linux/remoteproc.h>

#include <linux/reset.h>

#include "remoteproc_internal.h"

#define KEYSTONE_RPROC_LOCAL_ADDRESS_MASK	(SZ_16M - 1)

/**

 * struct keystone_rproc_mem - internal memory structure

 * @cpu_addr: MPU virtual address of the memory region

 * @bus_addr: Bus address used to access the memory region

 * @dev_addr: Device address of the memory region from DSP view

 * @size: Size of the memory region

 */

struct keystone_rproc_mem {

	void __iomem *cpu_addr;

	phys_addr_t bus_addr;

	u32 dev_addr;

	size_t size;

};

/**

 * struct keystone_rproc - keystone remote processor driver structure

 * @dev: cached device pointer

 * @rproc: remoteproc device handle

 * @mem: internal memory regions data

 * @num_mems: number of internal memory regions

 * @dev_ctrl: device control regmap handle

 * @reset: reset control handle

 * @boot_offset: boot register offset in @dev_ctrl regmap

 * @irq_ring: irq entry for vring

 * @irq_fault: irq entry for exception

 * @kick_gpio: gpio used for virtio kicks

 * @workqueue: workqueue for processing virtio interrupts

 */

struct keystone_rproc {

	struct device *dev;

	struct rproc *rproc;

	struct keystone_rproc_mem *mem;

	int num_mems;

	struct regmap *dev_ctrl;

	struct reset_control *reset;

	u32 boot_offset;

	int irq_ring;

	int irq_fault;

	int kick_gpio;

	struct work_struct workqueue;

};

/* Put the DSP processor into reset */

static void keystone_rproc_dsp_reset(struct keystone_rproc *ksproc)

{

	reset_control_assert(ksproc->reset);

}

/* Configure the boot address and boot the DSP processor */

static int keystone_rproc_dsp_boot(struct keystone_rproc *ksproc, u32 boot_addr)

{

	int ret;

	if (boot_addr & (SZ_1K - 1)) {

		dev_err(ksproc->dev, "invalid boot address 0x%x, must be aligned on a 1KB boundary\n",

			boot_addr);

		return -EINVAL;

	}

	ret = regmap_write(ksproc->dev_ctrl, ksproc->boot_offset, boot_addr);

	if (ret) {

		dev_err(ksproc->dev, "regmap_write of boot address failed, status = %d\n",

			ret);

		return ret;

	}

	reset_control_deassert(ksproc->reset);

	return 0;

}

/*

 * Process the remoteproc exceptions

 *

 * The exception reporting on Keystone DSP remote processors is very simple

 * compared to the equivalent processors on the OMAP family, it is notified

 * through a software-designed specific interrupt source in the IPC interrupt

 * generation register.

 *

 * This function just invokes the rproc_report_crash to report the exception

 * to the remoteproc driver core, to trigger a recovery.

 */

static irqreturn_t keystone_rproc_exception_interrupt(int irq, void *dev_id)

{

	struct keystone_rproc *ksproc = dev_id;

	rproc_report_crash(ksproc->rproc, RPROC_FATAL_ERROR);

	return IRQ_HANDLED;

}

/*

 * Main virtqueue message workqueue function

 *

 * This function is executed upon scheduling of the keystone remoteproc

 * driver's workqueue. The workqueue is scheduled by the vring ISR handler.

 *

 * There is no payload message indicating the virtqueue index as is the

 * case with mailbox-based implementations on OMAP family. As such, this

 * handler processes both the Tx and Rx virtqueue indices on every invocation.

 * The rproc_vq_interrupt function can detect if there are new unprocessed

 * messages or not (returns IRQ_NONE vs IRQ_HANDLED), but there is no need

 * to check for these return values. The index 0 triggering will process all

 * pending Rx buffers, and the index 1 triggering will process all newly

 * available Tx buffers and will wakeup any potentially blocked senders.

 *

 * NOTE:

 * 1. A payload could be added by using some of the source bits in the

 *    IPC interrupt generation registers, but this would need additional

 *    changes to the overall IPC stack, and currently there are no benefits

 *    of adapting that approach.

 * 2. The current logic is based on an inherent design assumption of supporting

 *    only 2 vrings, but this can be changed if needed.

 */

static void handle_event(struct work_struct *work)

{

	struct keystone_rproc *ksproc =

		container_of(work, struct keystone_rproc, workqueue);

	rproc_vq_interrupt(ksproc->rproc, 0);

	rproc_vq_interrupt(ksproc->rproc, 1);

}

/*

 * Interrupt handler for processing vring kicks from remote processor

 */

static irqreturn_t keystone_rproc_vring_interrupt(int irq, void *dev_id)

{

	struct keystone_rproc *ksproc = dev_id;

	schedule_work(&ksproc->workqueue);

	return IRQ_HANDLED;

}

/*

 * Power up the DSP remote processor.

 *

 * This function will be invoked only after the firmware for this rproc

 * was loaded, parsed successfully, and all of its resource requirements

 * were met.

 */

static int keystone_rproc_start(struct rproc *rproc)

{

	struct keystone_rproc *ksproc = rproc->priv;

	int ret;

	INIT_WORK(&ksproc->workqueue, handle_event);

	ret = request_irq(ksproc->irq_ring, keystone_rproc_vring_interrupt, 0,

			  dev_name(ksproc->dev), ksproc);

	if (ret) {

		dev_err(ksproc->dev, "failed to enable vring interrupt, ret = %d\n",

			ret);

		goto out;

	}

	ret = request_irq(ksproc->irq_fault, keystone_rproc_exception_interrupt,

			  0, dev_name(ksproc->dev), ksproc);

	if (ret) {

		dev_err(ksproc->dev, "failed to enable exception interrupt, ret = %d\n",

			ret);

		goto free_vring_irq;

	}

	ret = keystone_rproc_dsp_boot(ksproc, rproc->bootaddr);

	if (ret)

		goto free_exc_irq;

	return 0;

free_exc_irq:

	free_irq(ksproc->irq_fault, ksproc);

free_vring_irq:

	free_irq(ksproc->irq_ring, ksproc);

	flush_work(&ksproc->workqueue);

out:

	return ret;

}

/*

 * Stop the DSP remote processor.

 *

 * This function puts the DSP processor into reset, and finishes processing

 * of any pending messages.

 */

static int keystone_rproc_stop(struct rproc *rproc)

{

	struct keystone_rproc *ksproc = rproc->priv;

	keystone_rproc_dsp_reset(ksproc);

	free_irq(ksproc->irq_fault, ksproc);

	free_irq(ksproc->irq_ring, ksproc);

	flush_work(&ksproc->workqueue);

	return 0;

}

/*

 * Kick the remote processor to notify about pending unprocessed messages.

 * The vqid usage is not used and is inconsequential, as the kick is performed

 * through a simulated GPIO (a bit in an IPC interrupt-triggering register),

 * the remote processor is expected to process both its Tx and Rx virtqueues.

 */

static void keystone_rproc_kick(struct rproc *rproc, int vqid)

{

	struct keystone_rproc *ksproc = rproc->priv;

	if (WARN_ON(ksproc->kick_gpio < 0))

		return;

	gpio_set_value(ksproc->kick_gpio, 1);

}

/*

 * Custom function to translate a DSP device address (internal RAMs only) to a

 * kernel virtual address.  The DSPs can access their RAMs at either an internal

 * address visible only from a DSP, or at the SoC-level bus address. Both these

 * addresses need to be looked through for translation. The translated addresses

 * can be used either by the remoteproc core for loading (when using kernel

 * remoteproc loader), or by any rpmsg bus drivers.

 */

static void *keystone_rproc_da_to_va(struct rproc *rproc, u64 da, int len)

{

	struct keystone_rproc *ksproc = rproc->priv;

	void __iomem *va = NULL;

	phys_addr_t bus_addr;

	u32 dev_addr, offset;

	size_t size;

	int i;

	if (len <= 0)

		return NULL;

	for (i = 0; i < ksproc->num_mems; i++) {

		bus_addr = ksproc->mem[i].bus_addr;

		dev_addr = ksproc->mem[i].dev_addr;

		size = ksproc->mem[i].size;

		if (da < KEYSTONE_RPROC_LOCAL_ADDRESS_MASK) {

			/* handle DSP-view addresses */

			if ((da >= dev_addr) &&

			    ((da + len) <= (dev_addr + size))) {

				offset = da - dev_addr;

				va = ksproc->mem[i].cpu_addr + offset;

				break;

			}

		} else {

			/* handle SoC-view addresses */

			if ((da >= bus_addr) &&

			    (da + len) <= (bus_addr + size)) {

				offset = da - bus_addr;

				va = ksproc->mem[i].cpu_addr + offset;

				break;

			}

		}

	}

	return (__force void *)va;

}

static const struct rproc_ops keystone_rproc_ops = {

	.start		= keystone_rproc_start,

	.stop		= keystone_rproc_stop,

	.kick		= keystone_rproc_kick,

	.da_to_va	= keystone_rproc_da_to_va,

};

static int keystone_rproc_of_get_memories(struct platform_device *pdev,

					  struct keystone_rproc *ksproc)

{

	static const char * const mem_names[] = {"l2sram", "l1pram", "l1dram"};

	struct device *dev = &pdev->dev;

	struct resource *res;

	int num_mems = 0;

	int i;

	num_mems = ARRAY_SIZE(mem_names);

	ksproc->mem = devm_kcalloc(ksproc->dev, num_mems,

				   sizeof(*ksproc->mem), GFP_KERNEL);

	if (!ksproc->mem)

		return -ENOMEM;

	for (i = 0; i < num_mems; i++) {

		res = platform_get_resource_byname(pdev, IORESOURCE_MEM,

						   mem_names[i]);

		ksproc->mem[i].cpu_addr = devm_ioremap_resource(dev, res);

		if (IS_ERR(ksproc->mem[i].cpu_addr)) {

			dev_err(dev, "failed to parse and map %s memory\n",

				mem_names[i]);

			return PTR_ERR(ksproc->mem[i].cpu_addr);

		}

		ksproc->mem[i].bus_addr = res->start;

		ksproc->mem[i].dev_addr =

				res->start & KEYSTONE_RPROC_LOCAL_ADDRESS_MASK;

		ksproc->mem[i].size = resource_size(res);

		/* zero out memories to start in a pristine state */

		memset((__force void *)ksproc->mem[i].cpu_addr, 0,

		       ksproc->mem[i].size);

	}

	ksproc->num_mems = num_mems;

	return 0;

}

static int keystone_rproc_of_get_dev_syscon(struct platform_device *pdev,

					    struct keystone_rproc *ksproc)

{

	struct device_node *np = pdev->dev.of_node;

	struct device *dev = &pdev->dev;

	int ret;

	if (!of_property_read_bool(np, "ti,syscon-dev")) {

		dev_err(dev, "ti,syscon-dev property is absent\n");

		return -EINVAL;

	}

	ksproc->dev_ctrl =

		syscon_regmap_lookup_by_phandle(np, "ti,syscon-dev");

	if (IS_ERR(ksproc->dev_ctrl)) {

		ret = PTR_ERR(ksproc->dev_ctrl);

		return ret;

	}

	if (of_property_read_u32_index(np, "ti,syscon-dev", 1,

				       &ksproc->boot_offset)) {

		dev_err(dev, "couldn't read the boot register offset\n");

		return -EINVAL;

	}

	return 0;

}

static int keystone_rproc_probe(struct platform_device *pdev)

{

	struct device *dev = &pdev->dev;

	struct device_node *np = dev->of_node;

	struct keystone_rproc *ksproc;

	struct rproc *rproc;

	int dsp_id;

	char *fw_name = NULL;

	char *template = "keystone-dsp%d-fw";

	int name_len = 0;

	int ret = 0;

	if (!np) {

		dev_err(dev, "only DT-based devices are supported\n");

		return -ENODEV;

	}

	dsp_id = of_alias_get_id(np, "rproc");

	if (dsp_id < 0) {

		dev_warn(dev, "device does not have an alias id\n");

		return dsp_id;

	}

	/* construct a custom default fw name - subject to change in future */

	name_len = strlen(template); /* assuming a single digit alias */

	fw_name = devm_kzalloc(dev, name_len, GFP_KERNEL);

	if (!fw_name)

		return -ENOMEM;

	snprintf(fw_name, name_len, template, dsp_id);

	rproc = rproc_alloc(dev, dev_name(dev), &keystone_rproc_ops, fw_name,

			    sizeof(*ksproc));

	if (!rproc)

		return -ENOMEM;

	rproc->has_iommu = false;

	ksproc = rproc->priv;

	ksproc->rproc = rproc;

	ksproc->dev = dev;

	ret = keystone_rproc_of_get_dev_syscon(pdev, ksproc);

	if (ret)

		goto free_rproc;

	ksproc->reset = devm_reset_control_get(dev, NULL);

	if (IS_ERR(ksproc->reset)) {

		ret = PTR_ERR(ksproc->reset);

		goto free_rproc;

	}

	/* enable clock for accessing DSP internal memories */

	pm_runtime_enable(dev);

	ret = pm_runtime_get_sync(dev);

	if (ret < 0) {

		dev_err(dev, "failed to enable clock, status = %d\n", ret);

		pm_runtime_put_noidle(dev);

		goto disable_rpm;

	}

	ret = keystone_rproc_of_get_memories(pdev, ksproc);

	if (ret)

		goto disable_clk;

	ksproc->irq_ring = platform_get_irq_byname(pdev, "vring");

	if (ksproc->irq_ring < 0) {

		ret = ksproc->irq_ring;

		dev_err(dev, "failed to get vring interrupt, status = %d\n",

			ret);

		goto disable_clk;

	}

	ksproc->irq_fault = platform_get_irq_byname(pdev, "exception");

	if (ksproc->irq_fault < 0) {

		ret = ksproc->irq_fault;

		dev_err(dev, "failed to get exception interrupt, status = %d\n",

			ret);

		goto disable_clk;

	}

	ksproc->kick_gpio = of_get_named_gpio_flags(np, "kick-gpios", 0, NULL);

	if (ksproc->kick_gpio < 0) {

		ret = ksproc->kick_gpio;

		dev_err(dev, "failed to get gpio for virtio kicks, status = %d\n",

			ret);

		goto disable_clk;

	}

	if (of_reserved_mem_device_init(dev))

		dev_warn(dev, "device does not have specific CMA pool\n");

	ret = rproc_add(rproc);

	if (ret) {

		dev_err(dev, "failed to add register device with remoteproc core, status = %d\n",

			ret);

		goto release_mem;

	}

	platform_set_drvdata(pdev, ksproc);

	return 0;

release_mem:

	of_reserved_mem_device_release(dev);

disable_clk:

	pm_runtime_put_sync(dev);

disable_rpm:

	pm_runtime_disable(dev);

free_rproc:

	rproc_free(rproc);

	return ret;

}

static int keystone_rproc_remove(struct platform_device *pdev)

{

	struct keystone_rproc *ksproc = platform_get_drvdata(pdev);

	rproc_del(ksproc->rproc);

	pm_runtime_put_sync(&pdev->dev);

	pm_runtime_disable(&pdev->dev);

	rproc_free(ksproc->rproc);

	of_reserved_mem_device_release(&pdev->dev);

	return 0;

}

static const struct of_device_id keystone_rproc_of_match[] = {

	{ .compatible = "ti,k2hk-dsp", },

	{ .compatible = "ti,k2l-dsp", },

	{ .compatible = "ti,k2e-dsp", },

	{ /* sentinel */ },

};

MODULE_DEVICE_TABLE(of, keystone_rproc_of_match);

static struct platform_driver keystone_rproc_driver = {

	.probe	= keystone_rproc_probe,

	.remove	= keystone_rproc_remove,

	.driver	= {

		.name = "keystone-rproc",

		.of_match_table = keystone_rproc_of_match,

	},

};

module_platform_driver(keystone_rproc_driver);

MODULE_AUTHOR("Suman Anna <s-anna@ti.com>");

MODULE_LICENSE("GPL v2");

MODULE_DESCRIPTION("TI Keystone DSP Remoteproc driver");