linux/drivers/remoteproc/remoteproc_core.c
Bjorn Andersson a0c10687ec Revert "remoteproc: Merge table_ptr and cached_table pointers"
Following any fw_rsc_vdev entries in the resource table are two variable
length arrays, the first one reference vring resources and the second
one is the virtio config space.  The virtio config space is used by
virtio to communicate status and configuration changes and must as such
be shared with the remote.

The reverted commit incorrectly made any changes to the virtio config
space only affect the local copy, in an attempt to allowing memory
protection of the shared resource table.

This reverts commit cda8529346.
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
2016-12-30 03:26:31 -08:00

1581 lines
42 KiB
C

/*
* Remote Processor Framework
*
* Copyright (C) 2011 Texas Instruments, Inc.
* Copyright (C) 2011 Google, Inc.
*
* Ohad Ben-Cohen <ohad@wizery.com>
* Brian Swetland <swetland@google.com>
* Mark Grosen <mgrosen@ti.com>
* Fernando Guzman Lugo <fernando.lugo@ti.com>
* Suman Anna <s-anna@ti.com>
* Robert Tivy <rtivy@ti.com>
* Armando Uribe De Leon <x0095078@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.
*/
#define pr_fmt(fmt) "%s: " fmt, __func__
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/slab.h>
#include <linux/mutex.h>
#include <linux/dma-mapping.h>
#include <linux/firmware.h>
#include <linux/string.h>
#include <linux/debugfs.h>
#include <linux/remoteproc.h>
#include <linux/iommu.h>
#include <linux/idr.h>
#include <linux/elf.h>
#include <linux/crc32.h>
#include <linux/virtio_ids.h>
#include <linux/virtio_ring.h>
#include <asm/byteorder.h>
#include "remoteproc_internal.h"
static DEFINE_MUTEX(rproc_list_mutex);
static LIST_HEAD(rproc_list);
typedef int (*rproc_handle_resources_t)(struct rproc *rproc,
struct resource_table *table, int len);
typedef int (*rproc_handle_resource_t)(struct rproc *rproc,
void *, int offset, int avail);
/* Unique indices for remoteproc devices */
static DEFINE_IDA(rproc_dev_index);
static const char * const rproc_crash_names[] = {
[RPROC_MMUFAULT] = "mmufault",
[RPROC_WATCHDOG] = "watchdog",
[RPROC_FATAL_ERROR] = "fatal error",
};
/* translate rproc_crash_type to string */
static const char *rproc_crash_to_string(enum rproc_crash_type type)
{
if (type < ARRAY_SIZE(rproc_crash_names))
return rproc_crash_names[type];
return "unknown";
}
/*
* This is the IOMMU fault handler we register with the IOMMU API
* (when relevant; not all remote processors access memory through
* an IOMMU).
*
* IOMMU core will invoke this handler whenever the remote processor
* will try to access an unmapped device address.
*/
static int rproc_iommu_fault(struct iommu_domain *domain, struct device *dev,
unsigned long iova, int flags, void *token)
{
struct rproc *rproc = token;
dev_err(dev, "iommu fault: da 0x%lx flags 0x%x\n", iova, flags);
rproc_report_crash(rproc, RPROC_MMUFAULT);
/*
* Let the iommu core know we're not really handling this fault;
* we just used it as a recovery trigger.
*/
return -ENOSYS;
}
static int rproc_enable_iommu(struct rproc *rproc)
{
struct iommu_domain *domain;
struct device *dev = rproc->dev.parent;
int ret;
if (!rproc->has_iommu) {
dev_dbg(dev, "iommu not present\n");
return 0;
}
domain = iommu_domain_alloc(dev->bus);
if (!domain) {
dev_err(dev, "can't alloc iommu domain\n");
return -ENOMEM;
}
iommu_set_fault_handler(domain, rproc_iommu_fault, rproc);
ret = iommu_attach_device(domain, dev);
if (ret) {
dev_err(dev, "can't attach iommu device: %d\n", ret);
goto free_domain;
}
rproc->domain = domain;
return 0;
free_domain:
iommu_domain_free(domain);
return ret;
}
static void rproc_disable_iommu(struct rproc *rproc)
{
struct iommu_domain *domain = rproc->domain;
struct device *dev = rproc->dev.parent;
if (!domain)
return;
iommu_detach_device(domain, dev);
iommu_domain_free(domain);
}
/**
* rproc_da_to_va() - lookup the kernel virtual address for a remoteproc address
* @rproc: handle of a remote processor
* @da: remoteproc device address to translate
* @len: length of the memory region @da is pointing to
*
* Some remote processors will ask us to allocate them physically contiguous
* memory regions (which we call "carveouts"), and map them to specific
* device addresses (which are hardcoded in the firmware). They may also have
* dedicated memory regions internal to the processors, and use them either
* exclusively or alongside carveouts.
*
* They may then ask us to copy objects into specific device addresses (e.g.
* code/data sections) or expose us certain symbols in other device address
* (e.g. their trace buffer).
*
* This function is a helper function with which we can go over the allocated
* carveouts and translate specific device addresses to kernel virtual addresses
* so we can access the referenced memory. This function also allows to perform
* translations on the internal remoteproc memory regions through a platform
* implementation specific da_to_va ops, if present.
*
* The function returns a valid kernel address on success or NULL on failure.
*
* Note: phys_to_virt(iommu_iova_to_phys(rproc->domain, da)) will work too,
* but only on kernel direct mapped RAM memory. Instead, we're just using
* here the output of the DMA API for the carveouts, which should be more
* correct.
*/
void *rproc_da_to_va(struct rproc *rproc, u64 da, int len)
{
struct rproc_mem_entry *carveout;
void *ptr = NULL;
if (rproc->ops->da_to_va) {
ptr = rproc->ops->da_to_va(rproc, da, len);
if (ptr)
goto out;
}
list_for_each_entry(carveout, &rproc->carveouts, node) {
int offset = da - carveout->da;
/* try next carveout if da is too small */
if (offset < 0)
continue;
/* try next carveout if da is too large */
if (offset + len > carveout->len)
continue;
ptr = carveout->va + offset;
break;
}
out:
return ptr;
}
EXPORT_SYMBOL(rproc_da_to_va);
int rproc_alloc_vring(struct rproc_vdev *rvdev, int i)
{
struct rproc *rproc = rvdev->rproc;
struct device *dev = &rproc->dev;
struct rproc_vring *rvring = &rvdev->vring[i];
struct fw_rsc_vdev *rsc;
dma_addr_t dma;
void *va;
int ret, size, notifyid;
/* actual size of vring (in bytes) */
size = PAGE_ALIGN(vring_size(rvring->len, rvring->align));
/*
* Allocate non-cacheable memory for the vring. In the future
* this call will also configure the IOMMU for us
*/
va = dma_alloc_coherent(dev->parent, size, &dma, GFP_KERNEL);
if (!va) {
dev_err(dev->parent, "dma_alloc_coherent failed\n");
return -EINVAL;
}
/*
* Assign an rproc-wide unique index for this vring
* TODO: assign a notifyid for rvdev updates as well
* TODO: support predefined notifyids (via resource table)
*/
ret = idr_alloc(&rproc->notifyids, rvring, 0, 0, GFP_KERNEL);
if (ret < 0) {
dev_err(dev, "idr_alloc failed: %d\n", ret);
dma_free_coherent(dev->parent, size, va, dma);
return ret;
}
notifyid = ret;
/* Potentially bump max_notifyid */
if (notifyid > rproc->max_notifyid)
rproc->max_notifyid = notifyid;
dev_dbg(dev, "vring%d: va %p dma %pad size 0x%x idr %d\n",
i, va, &dma, size, notifyid);
rvring->va = va;
rvring->dma = dma;
rvring->notifyid = notifyid;
/*
* Let the rproc know the notifyid and da of this vring.
* Not all platforms use dma_alloc_coherent to automatically
* set up the iommu. In this case the device address (da) will
* hold the physical address and not the device address.
*/
rsc = (void *)rproc->table_ptr + rvdev->rsc_offset;
rsc->vring[i].da = dma;
rsc->vring[i].notifyid = notifyid;
return 0;
}
static int
rproc_parse_vring(struct rproc_vdev *rvdev, struct fw_rsc_vdev *rsc, int i)
{
struct rproc *rproc = rvdev->rproc;
struct device *dev = &rproc->dev;
struct fw_rsc_vdev_vring *vring = &rsc->vring[i];
struct rproc_vring *rvring = &rvdev->vring[i];
dev_dbg(dev, "vdev rsc: vring%d: da 0x%x, qsz %d, align %d\n",
i, vring->da, vring->num, vring->align);
/* verify queue size and vring alignment are sane */
if (!vring->num || !vring->align) {
dev_err(dev, "invalid qsz (%d) or alignment (%d)\n",
vring->num, vring->align);
return -EINVAL;
}
rvring->len = vring->num;
rvring->align = vring->align;
rvring->rvdev = rvdev;
return 0;
}
void rproc_free_vring(struct rproc_vring *rvring)
{
int size = PAGE_ALIGN(vring_size(rvring->len, rvring->align));
struct rproc *rproc = rvring->rvdev->rproc;
int idx = rvring->rvdev->vring - rvring;
struct fw_rsc_vdev *rsc;
dma_free_coherent(rproc->dev.parent, size, rvring->va, rvring->dma);
idr_remove(&rproc->notifyids, rvring->notifyid);
/* reset resource entry info */
rsc = (void *)rproc->table_ptr + rvring->rvdev->rsc_offset;
rsc->vring[idx].da = 0;
rsc->vring[idx].notifyid = -1;
}
static int rproc_vdev_do_probe(struct rproc_subdev *subdev)
{
struct rproc_vdev *rvdev = container_of(subdev, struct rproc_vdev, subdev);
return rproc_add_virtio_dev(rvdev, rvdev->id);
}
static void rproc_vdev_do_remove(struct rproc_subdev *subdev)
{
struct rproc_vdev *rvdev = container_of(subdev, struct rproc_vdev, subdev);
rproc_remove_virtio_dev(rvdev);
}
/**
* rproc_handle_vdev() - handle a vdev fw resource
* @rproc: the remote processor
* @rsc: the vring resource descriptor
* @avail: size of available data (for sanity checking the image)
*
* This resource entry requests the host to statically register a virtio
* device (vdev), and setup everything needed to support it. It contains
* everything needed to make it possible: the virtio device id, virtio
* device features, vrings information, virtio config space, etc...
*
* Before registering the vdev, the vrings are allocated from non-cacheable
* physically contiguous memory. Currently we only support two vrings per
* remote processor (temporary limitation). We might also want to consider
* doing the vring allocation only later when ->find_vqs() is invoked, and
* then release them upon ->del_vqs().
*
* Note: @da is currently not really handled correctly: we dynamically
* allocate it using the DMA API, ignoring requested hard coded addresses,
* and we don't take care of any required IOMMU programming. This is all
* going to be taken care of when the generic iommu-based DMA API will be
* merged. Meanwhile, statically-addressed iommu-based firmware images should
* use RSC_DEVMEM resource entries to map their required @da to the physical
* address of their base CMA region (ouch, hacky!).
*
* Returns 0 on success, or an appropriate error code otherwise
*/
static int rproc_handle_vdev(struct rproc *rproc, struct fw_rsc_vdev *rsc,
int offset, int avail)
{
struct device *dev = &rproc->dev;
struct rproc_vdev *rvdev;
int i, ret;
/* make sure resource isn't truncated */
if (sizeof(*rsc) + rsc->num_of_vrings * sizeof(struct fw_rsc_vdev_vring)
+ rsc->config_len > avail) {
dev_err(dev, "vdev rsc is truncated\n");
return -EINVAL;
}
/* make sure reserved bytes are zeroes */
if (rsc->reserved[0] || rsc->reserved[1]) {
dev_err(dev, "vdev rsc has non zero reserved bytes\n");
return -EINVAL;
}
dev_dbg(dev, "vdev rsc: id %d, dfeatures 0x%x, cfg len %d, %d vrings\n",
rsc->id, rsc->dfeatures, rsc->config_len, rsc->num_of_vrings);
/* we currently support only two vrings per rvdev */
if (rsc->num_of_vrings > ARRAY_SIZE(rvdev->vring)) {
dev_err(dev, "too many vrings: %d\n", rsc->num_of_vrings);
return -EINVAL;
}
rvdev = kzalloc(sizeof(*rvdev), GFP_KERNEL);
if (!rvdev)
return -ENOMEM;
kref_init(&rvdev->refcount);
rvdev->id = rsc->id;
rvdev->rproc = rproc;
/* parse the vrings */
for (i = 0; i < rsc->num_of_vrings; i++) {
ret = rproc_parse_vring(rvdev, rsc, i);
if (ret)
goto free_rvdev;
}
/* remember the resource offset*/
rvdev->rsc_offset = offset;
/* allocate the vring resources */
for (i = 0; i < rsc->num_of_vrings; i++) {
ret = rproc_alloc_vring(rvdev, i);
if (ret)
goto unwind_vring_allocations;
}
list_add_tail(&rvdev->node, &rproc->rvdevs);
rproc_add_subdev(rproc, &rvdev->subdev,
rproc_vdev_do_probe, rproc_vdev_do_remove);
return 0;
unwind_vring_allocations:
for (i--; i >= 0; i--)
rproc_free_vring(&rvdev->vring[i]);
free_rvdev:
kfree(rvdev);
return ret;
}
void rproc_vdev_release(struct kref *ref)
{
struct rproc_vdev *rvdev = container_of(ref, struct rproc_vdev, refcount);
struct rproc_vring *rvring;
struct rproc *rproc = rvdev->rproc;
int id;
for (id = 0; id < ARRAY_SIZE(rvdev->vring); id++) {
rvring = &rvdev->vring[id];
if (!rvring->va)
continue;
rproc_free_vring(rvring);
}
rproc_remove_subdev(rproc, &rvdev->subdev);
list_del(&rvdev->node);
kfree(rvdev);
}
/**
* rproc_handle_trace() - handle a shared trace buffer resource
* @rproc: the remote processor
* @rsc: the trace resource descriptor
* @avail: size of available data (for sanity checking the image)
*
* In case the remote processor dumps trace logs into memory,
* export it via debugfs.
*
* Currently, the 'da' member of @rsc should contain the device address
* where the remote processor is dumping the traces. Later we could also
* support dynamically allocating this address using the generic
* DMA API (but currently there isn't a use case for that).
*
* Returns 0 on success, or an appropriate error code otherwise
*/
static int rproc_handle_trace(struct rproc *rproc, struct fw_rsc_trace *rsc,
int offset, int avail)
{
struct rproc_mem_entry *trace;
struct device *dev = &rproc->dev;
void *ptr;
char name[15];
if (sizeof(*rsc) > avail) {
dev_err(dev, "trace rsc is truncated\n");
return -EINVAL;
}
/* make sure reserved bytes are zeroes */
if (rsc->reserved) {
dev_err(dev, "trace rsc has non zero reserved bytes\n");
return -EINVAL;
}
/* what's the kernel address of this resource ? */
ptr = rproc_da_to_va(rproc, rsc->da, rsc->len);
if (!ptr) {
dev_err(dev, "erroneous trace resource entry\n");
return -EINVAL;
}
trace = kzalloc(sizeof(*trace), GFP_KERNEL);
if (!trace)
return -ENOMEM;
/* set the trace buffer dma properties */
trace->len = rsc->len;
trace->va = ptr;
/* make sure snprintf always null terminates, even if truncating */
snprintf(name, sizeof(name), "trace%d", rproc->num_traces);
/* create the debugfs entry */
trace->priv = rproc_create_trace_file(name, rproc, trace);
if (!trace->priv) {
trace->va = NULL;
kfree(trace);
return -EINVAL;
}
list_add_tail(&trace->node, &rproc->traces);
rproc->num_traces++;
dev_dbg(dev, "%s added: va %p, da 0x%x, len 0x%x\n",
name, ptr, rsc->da, rsc->len);
return 0;
}
/**
* rproc_handle_devmem() - handle devmem resource entry
* @rproc: remote processor handle
* @rsc: the devmem resource entry
* @avail: size of available data (for sanity checking the image)
*
* Remote processors commonly need to access certain on-chip peripherals.
*
* Some of these remote processors access memory via an iommu device,
* and might require us to configure their iommu before they can access
* the on-chip peripherals they need.
*
* This resource entry is a request to map such a peripheral device.
*
* These devmem entries will contain the physical address of the device in
* the 'pa' member. If a specific device address is expected, then 'da' will
* contain it (currently this is the only use case supported). 'len' will
* contain the size of the physical region we need to map.
*
* Currently we just "trust" those devmem entries to contain valid physical
* addresses, but this is going to change: we want the implementations to
* tell us ranges of physical addresses the firmware is allowed to request,
* and not allow firmwares to request access to physical addresses that
* are outside those ranges.
*/
static int rproc_handle_devmem(struct rproc *rproc, struct fw_rsc_devmem *rsc,
int offset, int avail)
{
struct rproc_mem_entry *mapping;
struct device *dev = &rproc->dev;
int ret;
/* no point in handling this resource without a valid iommu domain */
if (!rproc->domain)
return -EINVAL;
if (sizeof(*rsc) > avail) {
dev_err(dev, "devmem rsc is truncated\n");
return -EINVAL;
}
/* make sure reserved bytes are zeroes */
if (rsc->reserved) {
dev_err(dev, "devmem rsc has non zero reserved bytes\n");
return -EINVAL;
}
mapping = kzalloc(sizeof(*mapping), GFP_KERNEL);
if (!mapping)
return -ENOMEM;
ret = iommu_map(rproc->domain, rsc->da, rsc->pa, rsc->len, rsc->flags);
if (ret) {
dev_err(dev, "failed to map devmem: %d\n", ret);
goto out;
}
/*
* We'll need this info later when we'll want to unmap everything
* (e.g. on shutdown).
*
* We can't trust the remote processor not to change the resource
* table, so we must maintain this info independently.
*/
mapping->da = rsc->da;
mapping->len = rsc->len;
list_add_tail(&mapping->node, &rproc->mappings);
dev_dbg(dev, "mapped devmem pa 0x%x, da 0x%x, len 0x%x\n",
rsc->pa, rsc->da, rsc->len);
return 0;
out:
kfree(mapping);
return ret;
}
/**
* rproc_handle_carveout() - handle phys contig memory allocation requests
* @rproc: rproc handle
* @rsc: the resource entry
* @avail: size of available data (for image validation)
*
* This function will handle firmware requests for allocation of physically
* contiguous memory regions.
*
* These request entries should come first in the firmware's resource table,
* as other firmware entries might request placing other data objects inside
* these memory regions (e.g. data/code segments, trace resource entries, ...).
*
* Allocating memory this way helps utilizing the reserved physical memory
* (e.g. CMA) more efficiently, and also minimizes the number of TLB entries
* needed to map it (in case @rproc is using an IOMMU). Reducing the TLB
* pressure is important; it may have a substantial impact on performance.
*/
static int rproc_handle_carveout(struct rproc *rproc,
struct fw_rsc_carveout *rsc,
int offset, int avail)
{
struct rproc_mem_entry *carveout, *mapping;
struct device *dev = &rproc->dev;
dma_addr_t dma;
void *va;
int ret;
if (sizeof(*rsc) > avail) {
dev_err(dev, "carveout rsc is truncated\n");
return -EINVAL;
}
/* make sure reserved bytes are zeroes */
if (rsc->reserved) {
dev_err(dev, "carveout rsc has non zero reserved bytes\n");
return -EINVAL;
}
dev_dbg(dev, "carveout rsc: name: %s, da 0x%x, pa 0x%x, len 0x%x, flags 0x%x\n",
rsc->name, rsc->da, rsc->pa, rsc->len, rsc->flags);
carveout = kzalloc(sizeof(*carveout), GFP_KERNEL);
if (!carveout)
return -ENOMEM;
va = dma_alloc_coherent(dev->parent, rsc->len, &dma, GFP_KERNEL);
if (!va) {
dev_err(dev->parent,
"failed to allocate dma memory: len 0x%x\n", rsc->len);
ret = -ENOMEM;
goto free_carv;
}
dev_dbg(dev, "carveout va %p, dma %pad, len 0x%x\n",
va, &dma, rsc->len);
/*
* Ok, this is non-standard.
*
* Sometimes we can't rely on the generic iommu-based DMA API
* to dynamically allocate the device address and then set the IOMMU
* tables accordingly, because some remote processors might
* _require_ us to use hard coded device addresses that their
* firmware was compiled with.
*
* In this case, we must use the IOMMU API directly and map
* the memory to the device address as expected by the remote
* processor.
*
* Obviously such remote processor devices should not be configured
* to use the iommu-based DMA API: we expect 'dma' to contain the
* physical address in this case.
*/
if (rproc->domain) {
mapping = kzalloc(sizeof(*mapping), GFP_KERNEL);
if (!mapping) {
ret = -ENOMEM;
goto dma_free;
}
ret = iommu_map(rproc->domain, rsc->da, dma, rsc->len,
rsc->flags);
if (ret) {
dev_err(dev, "iommu_map failed: %d\n", ret);
goto free_mapping;
}
/*
* We'll need this info later when we'll want to unmap
* everything (e.g. on shutdown).
*
* We can't trust the remote processor not to change the
* resource table, so we must maintain this info independently.
*/
mapping->da = rsc->da;
mapping->len = rsc->len;
list_add_tail(&mapping->node, &rproc->mappings);
dev_dbg(dev, "carveout mapped 0x%x to %pad\n",
rsc->da, &dma);
}
/*
* Some remote processors might need to know the pa
* even though they are behind an IOMMU. E.g., OMAP4's
* remote M3 processor needs this so it can control
* on-chip hardware accelerators that are not behind
* the IOMMU, and therefor must know the pa.
*
* Generally we don't want to expose physical addresses
* if we don't have to (remote processors are generally
* _not_ trusted), so we might want to do this only for
* remote processor that _must_ have this (e.g. OMAP4's
* dual M3 subsystem).
*
* Non-IOMMU processors might also want to have this info.
* In this case, the device address and the physical address
* are the same.
*/
rsc->pa = dma;
carveout->va = va;
carveout->len = rsc->len;
carveout->dma = dma;
carveout->da = rsc->da;
list_add_tail(&carveout->node, &rproc->carveouts);
return 0;
free_mapping:
kfree(mapping);
dma_free:
dma_free_coherent(dev->parent, rsc->len, va, dma);
free_carv:
kfree(carveout);
return ret;
}
/*
* A lookup table for resource handlers. The indices are defined in
* enum fw_resource_type.
*/
static rproc_handle_resource_t rproc_loading_handlers[RSC_LAST] = {
[RSC_CARVEOUT] = (rproc_handle_resource_t)rproc_handle_carveout,
[RSC_DEVMEM] = (rproc_handle_resource_t)rproc_handle_devmem,
[RSC_TRACE] = (rproc_handle_resource_t)rproc_handle_trace,
[RSC_VDEV] = (rproc_handle_resource_t)rproc_handle_vdev,
};
/* handle firmware resource entries before booting the remote processor */
static int rproc_handle_resources(struct rproc *rproc, int len,
rproc_handle_resource_t handlers[RSC_LAST])
{
struct device *dev = &rproc->dev;
rproc_handle_resource_t handler;
int ret = 0, i;
for (i = 0; i < rproc->table_ptr->num; i++) {
int offset = rproc->table_ptr->offset[i];
struct fw_rsc_hdr *hdr = (void *)rproc->table_ptr + offset;
int avail = len - offset - sizeof(*hdr);
void *rsc = (void *)hdr + sizeof(*hdr);
/* make sure table isn't truncated */
if (avail < 0) {
dev_err(dev, "rsc table is truncated\n");
return -EINVAL;
}
dev_dbg(dev, "rsc: type %d\n", hdr->type);
if (hdr->type >= RSC_LAST) {
dev_warn(dev, "unsupported resource %d\n", hdr->type);
continue;
}
handler = handlers[hdr->type];
if (!handler)
continue;
ret = handler(rproc, rsc, offset + sizeof(*hdr), avail);
if (ret)
break;
}
return ret;
}
static int rproc_probe_subdevices(struct rproc *rproc)
{
struct rproc_subdev *subdev;
int ret;
list_for_each_entry(subdev, &rproc->subdevs, node) {
ret = subdev->probe(subdev);
if (ret)
goto unroll_registration;
}
return 0;
unroll_registration:
list_for_each_entry_continue_reverse(subdev, &rproc->subdevs, node)
subdev->remove(subdev);
return ret;
}
static void rproc_remove_subdevices(struct rproc *rproc)
{
struct rproc_subdev *subdev;
list_for_each_entry(subdev, &rproc->subdevs, node)
subdev->remove(subdev);
}
/**
* rproc_resource_cleanup() - clean up and free all acquired resources
* @rproc: rproc handle
*
* This function will free all resources acquired for @rproc, and it
* is called whenever @rproc either shuts down or fails to boot.
*/
static void rproc_resource_cleanup(struct rproc *rproc)
{
struct rproc_mem_entry *entry, *tmp;
struct rproc_vdev *rvdev, *rvtmp;
struct device *dev = &rproc->dev;
/* clean up debugfs trace entries */
list_for_each_entry_safe(entry, tmp, &rproc->traces, node) {
rproc_remove_trace_file(entry->priv);
rproc->num_traces--;
list_del(&entry->node);
kfree(entry);
}
/* clean up iommu mapping entries */
list_for_each_entry_safe(entry, tmp, &rproc->mappings, node) {
size_t unmapped;
unmapped = iommu_unmap(rproc->domain, entry->da, entry->len);
if (unmapped != entry->len) {
/* nothing much to do besides complaining */
dev_err(dev, "failed to unmap %u/%zu\n", entry->len,
unmapped);
}
list_del(&entry->node);
kfree(entry);
}
/* clean up carveout allocations */
list_for_each_entry_safe(entry, tmp, &rproc->carveouts, node) {
dma_free_coherent(dev->parent, entry->len, entry->va,
entry->dma);
list_del(&entry->node);
kfree(entry);
}
/* clean up remote vdev entries */
list_for_each_entry_safe(rvdev, rvtmp, &rproc->rvdevs, node)
kref_put(&rvdev->refcount, rproc_vdev_release);
}
/*
* take a firmware and boot a remote processor with it.
*/
static int rproc_fw_boot(struct rproc *rproc, const struct firmware *fw)
{
struct device *dev = &rproc->dev;
const char *name = rproc->firmware;
struct resource_table *table, *loaded_table;
int ret, tablesz;
ret = rproc_fw_sanity_check(rproc, fw);
if (ret)
return ret;
dev_info(dev, "Booting fw image %s, size %zd\n", name, fw->size);
/*
* if enabling an IOMMU isn't relevant for this rproc, this is
* just a nop
*/
ret = rproc_enable_iommu(rproc);
if (ret) {
dev_err(dev, "can't enable iommu: %d\n", ret);
return ret;
}
rproc->bootaddr = rproc_get_boot_addr(rproc, fw);
ret = -EINVAL;
/* look for the resource table */
table = rproc_find_rsc_table(rproc, fw, &tablesz);
if (!table) {
dev_err(dev, "Failed to find resource table\n");
goto clean_up;
}
/*
* Create a copy of the resource table. When a virtio device starts
* and calls vring_new_virtqueue() the address of the allocated vring
* will be stored in the cached_table. Before the device is started,
* cached_table will be copied into device memory.
*/
rproc->cached_table = kmemdup(table, tablesz, GFP_KERNEL);
if (!rproc->cached_table)
goto clean_up;
rproc->table_ptr = rproc->cached_table;
/* reset max_notifyid */
rproc->max_notifyid = -1;
/* handle fw resources which are required to boot rproc */
ret = rproc_handle_resources(rproc, tablesz, rproc_loading_handlers);
if (ret) {
dev_err(dev, "Failed to process resources: %d\n", ret);
goto clean_up_resources;
}
/* load the ELF segments to memory */
ret = rproc_load_segments(rproc, fw);
if (ret) {
dev_err(dev, "Failed to load program segments: %d\n", ret);
goto clean_up_resources;
}
/*
* The starting device has been given the rproc->cached_table as the
* resource table. The address of the vring along with the other
* allocated resources (carveouts etc) is stored in cached_table.
* In order to pass this information to the remote device we must copy
* this information to device memory. We also update the table_ptr so
* that any subsequent changes will be applied to the loaded version.
*/
loaded_table = rproc_find_loaded_rsc_table(rproc, fw);
if (loaded_table) {
memcpy(loaded_table, rproc->cached_table, tablesz);
rproc->table_ptr = loaded_table;
}
/* power up the remote processor */
ret = rproc->ops->start(rproc);
if (ret) {
dev_err(dev, "can't start rproc %s: %d\n", rproc->name, ret);
goto clean_up_resources;
}
/* probe any subdevices for the remote processor */
ret = rproc_probe_subdevices(rproc);
if (ret) {
dev_err(dev, "failed to probe subdevices for %s: %d\n",
rproc->name, ret);
goto stop_rproc;
}
rproc->state = RPROC_RUNNING;
dev_info(dev, "remote processor %s is now up\n", rproc->name);
return 0;
stop_rproc:
rproc->ops->stop(rproc);
clean_up_resources:
rproc_resource_cleanup(rproc);
clean_up:
kfree(rproc->cached_table);
rproc->cached_table = NULL;
rproc->table_ptr = NULL;
rproc_disable_iommu(rproc);
return ret;
}
/*
* take a firmware and look for virtio devices to register.
*
* Note: this function is called asynchronously upon registration of the
* remote processor (so we must wait until it completes before we try
* to unregister the device. one other option is just to use kref here,
* that might be cleaner).
*/
static void rproc_fw_config_virtio(const struct firmware *fw, void *context)
{
struct rproc *rproc = context;
/* if rproc is marked always-on, request it to boot */
if (rproc->auto_boot)
rproc_boot(rproc);
release_firmware(fw);
/* allow rproc_del() contexts, if any, to proceed */
complete_all(&rproc->firmware_loading_complete);
}
static int rproc_add_virtio_devices(struct rproc *rproc)
{
int ret;
/* rproc_del() calls must wait until async loader completes */
init_completion(&rproc->firmware_loading_complete);
/*
* We must retrieve early virtio configuration info from
* the firmware (e.g. whether to register a virtio device,
* what virtio features does it support, ...).
*
* We're initiating an asynchronous firmware loading, so we can
* be built-in kernel code, without hanging the boot process.
*/
ret = request_firmware_nowait(THIS_MODULE, FW_ACTION_HOTPLUG,
rproc->firmware, &rproc->dev, GFP_KERNEL,
rproc, rproc_fw_config_virtio);
if (ret < 0) {
dev_err(&rproc->dev, "request_firmware_nowait err: %d\n", ret);
complete_all(&rproc->firmware_loading_complete);
}
return ret;
}
/**
* rproc_trigger_recovery() - recover a remoteproc
* @rproc: the remote processor
*
* The recovery is done by resetting all the virtio devices, that way all the
* rpmsg drivers will be reseted along with the remote processor making the
* remoteproc functional again.
*
* This function can sleep, so it cannot be called from atomic context.
*/
int rproc_trigger_recovery(struct rproc *rproc)
{
dev_err(&rproc->dev, "recovering %s\n", rproc->name);
init_completion(&rproc->crash_comp);
/* shut down the remote */
/* TODO: make sure this works with rproc->power > 1 */
rproc_shutdown(rproc);
/* wait until there is no more rproc users */
wait_for_completion(&rproc->crash_comp);
/*
* boot the remote processor up again
*/
rproc_boot(rproc);
return 0;
}
/**
* rproc_crash_handler_work() - handle a crash
*
* This function needs to handle everything related to a crash, like cpu
* registers and stack dump, information to help to debug the fatal error, etc.
*/
static void rproc_crash_handler_work(struct work_struct *work)
{
struct rproc *rproc = container_of(work, struct rproc, crash_handler);
struct device *dev = &rproc->dev;
dev_dbg(dev, "enter %s\n", __func__);
mutex_lock(&rproc->lock);
if (rproc->state == RPROC_CRASHED || rproc->state == RPROC_OFFLINE) {
/* handle only the first crash detected */
mutex_unlock(&rproc->lock);
return;
}
rproc->state = RPROC_CRASHED;
dev_err(dev, "handling crash #%u in %s\n", ++rproc->crash_cnt,
rproc->name);
mutex_unlock(&rproc->lock);
if (!rproc->recovery_disabled)
rproc_trigger_recovery(rproc);
}
/**
* __rproc_boot() - boot a remote processor
* @rproc: handle of a remote processor
*
* Boot a remote processor (i.e. load its firmware, power it on, ...).
*
* If the remote processor is already powered on, this function immediately
* returns (successfully).
*
* Returns 0 on success, and an appropriate error value otherwise.
*/
static int __rproc_boot(struct rproc *rproc)
{
const struct firmware *firmware_p;
struct device *dev;
int ret;
if (!rproc) {
pr_err("invalid rproc handle\n");
return -EINVAL;
}
dev = &rproc->dev;
ret = mutex_lock_interruptible(&rproc->lock);
if (ret) {
dev_err(dev, "can't lock rproc %s: %d\n", rproc->name, ret);
return ret;
}
/* skip the boot process if rproc is already powered up */
if (atomic_inc_return(&rproc->power) > 1) {
ret = 0;
goto unlock_mutex;
}
dev_info(dev, "powering up %s\n", rproc->name);
/* load firmware */
ret = request_firmware(&firmware_p, rproc->firmware, dev);
if (ret < 0) {
dev_err(dev, "request_firmware failed: %d\n", ret);
goto downref_rproc;
}
ret = rproc_fw_boot(rproc, firmware_p);
release_firmware(firmware_p);
downref_rproc:
if (ret)
atomic_dec(&rproc->power);
unlock_mutex:
mutex_unlock(&rproc->lock);
return ret;
}
/**
* rproc_boot() - boot a remote processor
* @rproc: handle of a remote processor
*/
int rproc_boot(struct rproc *rproc)
{
return __rproc_boot(rproc);
}
EXPORT_SYMBOL(rproc_boot);
/**
* rproc_shutdown() - power off the remote processor
* @rproc: the remote processor
*
* Power off a remote processor (previously booted with rproc_boot()).
*
* In case @rproc is still being used by an additional user(s), then
* this function will just decrement the power refcount and exit,
* without really powering off the device.
*
* Every call to rproc_boot() must (eventually) be accompanied by a call
* to rproc_shutdown(). Calling rproc_shutdown() redundantly is a bug.
*
* Notes:
* - we're not decrementing the rproc's refcount, only the power refcount.
* which means that the @rproc handle stays valid even after rproc_shutdown()
* returns, and users can still use it with a subsequent rproc_boot(), if
* needed.
*/
void rproc_shutdown(struct rproc *rproc)
{
struct device *dev = &rproc->dev;
int ret;
ret = mutex_lock_interruptible(&rproc->lock);
if (ret) {
dev_err(dev, "can't lock rproc %s: %d\n", rproc->name, ret);
return;
}
/* if the remote proc is still needed, bail out */
if (!atomic_dec_and_test(&rproc->power))
goto out;
/* remove any subdevices for the remote processor */
rproc_remove_subdevices(rproc);
/* power off the remote processor */
ret = rproc->ops->stop(rproc);
if (ret) {
atomic_inc(&rproc->power);
dev_err(dev, "can't stop rproc: %d\n", ret);
goto out;
}
/* clean up all acquired resources */
rproc_resource_cleanup(rproc);
rproc_disable_iommu(rproc);
/* Free the copy of the resource table */
kfree(rproc->cached_table);
rproc->cached_table = NULL;
rproc->table_ptr = NULL;
/* if in crash state, unlock crash handler */
if (rproc->state == RPROC_CRASHED)
complete_all(&rproc->crash_comp);
rproc->state = RPROC_OFFLINE;
dev_info(dev, "stopped remote processor %s\n", rproc->name);
out:
mutex_unlock(&rproc->lock);
}
EXPORT_SYMBOL(rproc_shutdown);
/**
* rproc_get_by_phandle() - find a remote processor by phandle
* @phandle: phandle to the rproc
*
* Finds an rproc handle using the remote processor's phandle, and then
* return a handle to the rproc.
*
* This function increments the remote processor's refcount, so always
* use rproc_put() to decrement it back once rproc isn't needed anymore.
*
* Returns the rproc handle on success, and NULL on failure.
*/
#ifdef CONFIG_OF
struct rproc *rproc_get_by_phandle(phandle phandle)
{
struct rproc *rproc = NULL, *r;
struct device_node *np;
np = of_find_node_by_phandle(phandle);
if (!np)
return NULL;
mutex_lock(&rproc_list_mutex);
list_for_each_entry(r, &rproc_list, node) {
if (r->dev.parent && r->dev.parent->of_node == np) {
/* prevent underlying implementation from being removed */
if (!try_module_get(r->dev.parent->driver->owner)) {
dev_err(&r->dev, "can't get owner\n");
break;
}
rproc = r;
get_device(&rproc->dev);
break;
}
}
mutex_unlock(&rproc_list_mutex);
of_node_put(np);
return rproc;
}
#else
struct rproc *rproc_get_by_phandle(phandle phandle)
{
return NULL;
}
#endif
EXPORT_SYMBOL(rproc_get_by_phandle);
/**
* rproc_add() - register a remote processor
* @rproc: the remote processor handle to register
*
* Registers @rproc with the remoteproc framework, after it has been
* allocated with rproc_alloc().
*
* This is called by the platform-specific rproc implementation, whenever
* a new remote processor device is probed.
*
* Returns 0 on success and an appropriate error code otherwise.
*
* Note: this function initiates an asynchronous firmware loading
* context, which will look for virtio devices supported by the rproc's
* firmware.
*
* If found, those virtio devices will be created and added, so as a result
* of registering this remote processor, additional virtio drivers might be
* probed.
*/
int rproc_add(struct rproc *rproc)
{
struct device *dev = &rproc->dev;
int ret;
ret = device_add(dev);
if (ret < 0)
return ret;
dev_info(dev, "%s is available\n", rproc->name);
/* create debugfs entries */
rproc_create_debug_dir(rproc);
ret = rproc_add_virtio_devices(rproc);
if (ret < 0)
return ret;
/* expose to rproc_get_by_phandle users */
mutex_lock(&rproc_list_mutex);
list_add(&rproc->node, &rproc_list);
mutex_unlock(&rproc_list_mutex);
return 0;
}
EXPORT_SYMBOL(rproc_add);
/**
* rproc_type_release() - release a remote processor instance
* @dev: the rproc's device
*
* This function should _never_ be called directly.
*
* It will be called by the driver core when no one holds a valid pointer
* to @dev anymore.
*/
static void rproc_type_release(struct device *dev)
{
struct rproc *rproc = container_of(dev, struct rproc, dev);
dev_info(&rproc->dev, "releasing %s\n", rproc->name);
rproc_delete_debug_dir(rproc);
idr_destroy(&rproc->notifyids);
if (rproc->index >= 0)
ida_simple_remove(&rproc_dev_index, rproc->index);
kfree(rproc->firmware);
kfree(rproc);
}
static struct device_type rproc_type = {
.name = "remoteproc",
.release = rproc_type_release,
};
/**
* rproc_alloc() - allocate a remote processor handle
* @dev: the underlying device
* @name: name of this remote processor
* @ops: platform-specific handlers (mainly start/stop)
* @firmware: name of firmware file to load, can be NULL
* @len: length of private data needed by the rproc driver (in bytes)
*
* Allocates a new remote processor handle, but does not register
* it yet. if @firmware is NULL, a default name is used.
*
* This function should be used by rproc implementations during initialization
* of the remote processor.
*
* After creating an rproc handle using this function, and when ready,
* implementations should then call rproc_add() to complete
* the registration of the remote processor.
*
* On success the new rproc is returned, and on failure, NULL.
*
* Note: _never_ directly deallocate @rproc, even if it was not registered
* yet. Instead, when you need to unroll rproc_alloc(), use rproc_free().
*/
struct rproc *rproc_alloc(struct device *dev, const char *name,
const struct rproc_ops *ops,
const char *firmware, int len)
{
struct rproc *rproc;
char *p, *template = "rproc-%s-fw";
int name_len;
if (!dev || !name || !ops)
return NULL;
if (!firmware) {
/*
* If the caller didn't pass in a firmware name then
* construct a default name.
*/
name_len = strlen(name) + strlen(template) - 2 + 1;
p = kmalloc(name_len, GFP_KERNEL);
if (!p)
return NULL;
snprintf(p, name_len, template, name);
} else {
p = kstrdup(firmware, GFP_KERNEL);
if (!p)
return NULL;
}
rproc = kzalloc(sizeof(struct rproc) + len, GFP_KERNEL);
if (!rproc) {
kfree(p);
return NULL;
}
rproc->firmware = p;
rproc->name = name;
rproc->ops = ops;
rproc->priv = &rproc[1];
rproc->auto_boot = true;
device_initialize(&rproc->dev);
rproc->dev.parent = dev;
rproc->dev.type = &rproc_type;
rproc->dev.class = &rproc_class;
/* Assign a unique device index and name */
rproc->index = ida_simple_get(&rproc_dev_index, 0, 0, GFP_KERNEL);
if (rproc->index < 0) {
dev_err(dev, "ida_simple_get failed: %d\n", rproc->index);
put_device(&rproc->dev);
return NULL;
}
dev_set_name(&rproc->dev, "remoteproc%d", rproc->index);
atomic_set(&rproc->power, 0);
/* Set ELF as the default fw_ops handler */
rproc->fw_ops = &rproc_elf_fw_ops;
mutex_init(&rproc->lock);
idr_init(&rproc->notifyids);
INIT_LIST_HEAD(&rproc->carveouts);
INIT_LIST_HEAD(&rproc->mappings);
INIT_LIST_HEAD(&rproc->traces);
INIT_LIST_HEAD(&rproc->rvdevs);
INIT_LIST_HEAD(&rproc->subdevs);
INIT_WORK(&rproc->crash_handler, rproc_crash_handler_work);
init_completion(&rproc->crash_comp);
rproc->state = RPROC_OFFLINE;
return rproc;
}
EXPORT_SYMBOL(rproc_alloc);
/**
* rproc_free() - unroll rproc_alloc()
* @rproc: the remote processor handle
*
* This function decrements the rproc dev refcount.
*
* If no one holds any reference to rproc anymore, then its refcount would
* now drop to zero, and it would be freed.
*/
void rproc_free(struct rproc *rproc)
{
put_device(&rproc->dev);
}
EXPORT_SYMBOL(rproc_free);
/**
* rproc_put() - release rproc reference
* @rproc: the remote processor handle
*
* This function decrements the rproc dev refcount.
*
* If no one holds any reference to rproc anymore, then its refcount would
* now drop to zero, and it would be freed.
*/
void rproc_put(struct rproc *rproc)
{
module_put(rproc->dev.parent->driver->owner);
put_device(&rproc->dev);
}
EXPORT_SYMBOL(rproc_put);
/**
* rproc_del() - unregister a remote processor
* @rproc: rproc handle to unregister
*
* This function should be called when the platform specific rproc
* implementation decides to remove the rproc device. it should
* _only_ be called if a previous invocation of rproc_add()
* has completed successfully.
*
* After rproc_del() returns, @rproc isn't freed yet, because
* of the outstanding reference created by rproc_alloc. To decrement that
* one last refcount, one still needs to call rproc_free().
*
* Returns 0 on success and -EINVAL if @rproc isn't valid.
*/
int rproc_del(struct rproc *rproc)
{
if (!rproc)
return -EINVAL;
/* if rproc is just being registered, wait */
wait_for_completion(&rproc->firmware_loading_complete);
/* if rproc is marked always-on, rproc_add() booted it */
/* TODO: make sure this works with rproc->power > 1 */
if (rproc->auto_boot)
rproc_shutdown(rproc);
/* the rproc is downref'ed as soon as it's removed from the klist */
mutex_lock(&rproc_list_mutex);
list_del(&rproc->node);
mutex_unlock(&rproc_list_mutex);
device_del(&rproc->dev);
return 0;
}
EXPORT_SYMBOL(rproc_del);
/**
* rproc_add_subdev() - add a subdevice to a remoteproc
* @rproc: rproc handle to add the subdevice to
* @subdev: subdev handle to register
* @probe: function to call when the rproc boots
* @remove: function to call when the rproc shuts down
*/
void rproc_add_subdev(struct rproc *rproc,
struct rproc_subdev *subdev,
int (*probe)(struct rproc_subdev *subdev),
void (*remove)(struct rproc_subdev *subdev))
{
subdev->probe = probe;
subdev->remove = remove;
list_add_tail(&subdev->node, &rproc->subdevs);
}
EXPORT_SYMBOL(rproc_add_subdev);
/**
* rproc_remove_subdev() - remove a subdevice from a remoteproc
* @rproc: rproc handle to remove the subdevice from
* @subdev: subdev handle, previously registered with rproc_add_subdev()
*/
void rproc_remove_subdev(struct rproc *rproc, struct rproc_subdev *subdev)
{
list_del(&subdev->node);
}
EXPORT_SYMBOL(rproc_remove_subdev);
/**
* rproc_report_crash() - rproc crash reporter function
* @rproc: remote processor
* @type: crash type
*
* This function must be called every time a crash is detected by the low-level
* drivers implementing a specific remoteproc. This should not be called from a
* non-remoteproc driver.
*
* This function can be called from atomic/interrupt context.
*/
void rproc_report_crash(struct rproc *rproc, enum rproc_crash_type type)
{
if (!rproc) {
pr_err("NULL rproc pointer\n");
return;
}
dev_err(&rproc->dev, "crash detected in %s: type %s\n",
rproc->name, rproc_crash_to_string(type));
/* create a new task to handle the error */
schedule_work(&rproc->crash_handler);
}
EXPORT_SYMBOL(rproc_report_crash);
static int __init remoteproc_init(void)
{
rproc_init_sysfs();
rproc_init_debugfs();
return 0;
}
module_init(remoteproc_init);
static void __exit remoteproc_exit(void)
{
ida_destroy(&rproc_dev_index);
rproc_exit_debugfs();
rproc_exit_sysfs();
}
module_exit(remoteproc_exit);
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("Generic Remote Processor Framework");