keystone_remoteproc.c
// SPDX-License-Identifier: GPL-2.0-only
/*
* TI Keystone DSP remoteproc driver
*
* Copyright (C) 2015-2017 Texas Instruments Incorporated - http://www.ti.com/
*/
#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_exclusive(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;
goto disable_clk;
}
ksproc->irq_fault = platform_get_irq_byname(pdev, "exception");
if (ksproc->irq_fault < 0) {
ret = ksproc->irq_fault;
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");
/* ensure the DSP is in reset before loading firmware */
ret = reset_control_status(ksproc->reset);
if (ret < 0) {
dev_err(dev, "failed to get reset status, status = %d\n", ret);
goto release_mem;
} else if (ret == 0) {
WARN(1, "device is not in reset\n");
keystone_rproc_dsp_reset(ksproc);
}
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", },
{ .compatible = "ti,k2g-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");