u-boot/drivers/core/uclass.c
Simon Glass 1e9ced28f1 dm: core: Don't allow uclass use before ready
At present it is possible to call uclass_get() before driver model is
inited. In fact this happens on x86 boards which use Intel FSPv1, since
mrccache_get_region() tries to get the SPI flash device very early
during init.

This has always been undefined behaviour. Previously it generally worked,
i.e. returned an error code without crashing, because gd->uclass_root_s
is zeroed and the uclass can be added despite driver model not being
ready, due to the way lists are implemented. With the change to use a
gd->uclass_root pointer, this no-longer works. For example, it causes a
hang on minnowmax.

Fix this by adding a check that driver model is ready when uclass_get() is
called. This function is called in the process of locating any device, so
it is a good place to add the check.

This fixes booting on minnowmax.

Signed-off-by: Simon Glass <sjg@chromium.org>
Fixes: 8a715530bb ("dm: core: Allow the uclass list to move")
2021-08-08 11:27:27 -06:00

789 lines
14 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (c) 2013 Google, Inc
*
* (C) Copyright 2012
* Pavel Herrmann <morpheus.ibis@gmail.com>
*/
#define LOG_CATEGORY LOGC_DM
#include <common.h>
#include <dm.h>
#include <errno.h>
#include <log.h>
#include <malloc.h>
#include <asm/global_data.h>
#include <dm/device.h>
#include <dm/device-internal.h>
#include <dm/lists.h>
#include <dm/uclass.h>
#include <dm/uclass-internal.h>
#include <dm/util.h>
DECLARE_GLOBAL_DATA_PTR;
struct uclass *uclass_find(enum uclass_id key)
{
struct uclass *uc;
if (!gd->dm_root)
return NULL;
/*
* TODO(sjg@chromium.org): Optimise this, perhaps moving the found
* node to the start of the list, or creating a linear array mapping
* id to node.
*/
list_for_each_entry(uc, gd->uclass_root, sibling_node) {
if (uc->uc_drv->id == key)
return uc;
}
return NULL;
}
/**
* uclass_add() - Create new uclass in list
* @id: Id number to create
* @ucp: Returns pointer to uclass, or NULL on error
* @return 0 on success, -ve on error
*
* The new uclass is added to the list. There must be only one uclass for
* each id.
*/
static int uclass_add(enum uclass_id id, struct uclass **ucp)
{
struct uclass_driver *uc_drv;
struct uclass *uc;
int ret;
*ucp = NULL;
uc_drv = lists_uclass_lookup(id);
if (!uc_drv) {
debug("Cannot find uclass for id %d: please add the UCLASS_DRIVER() declaration for this UCLASS_... id\n",
id);
/*
* Use a strange error to make this case easier to find. When
* a uclass is not available it can prevent driver model from
* starting up and this failure is otherwise hard to debug.
*/
return -EPFNOSUPPORT;
}
uc = calloc(1, sizeof(*uc));
if (!uc)
return -ENOMEM;
if (uc_drv->priv_auto) {
void *ptr;
ptr = calloc(1, uc_drv->priv_auto);
if (!ptr) {
ret = -ENOMEM;
goto fail_mem;
}
uclass_set_priv(uc, ptr);
}
uc->uc_drv = uc_drv;
INIT_LIST_HEAD(&uc->sibling_node);
INIT_LIST_HEAD(&uc->dev_head);
list_add(&uc->sibling_node, DM_UCLASS_ROOT_NON_CONST);
if (uc_drv->init) {
ret = uc_drv->init(uc);
if (ret)
goto fail;
}
*ucp = uc;
return 0;
fail:
if (uc_drv->priv_auto) {
free(uclass_get_priv(uc));
uclass_set_priv(uc, NULL);
}
list_del(&uc->sibling_node);
fail_mem:
free(uc);
return ret;
}
int uclass_destroy(struct uclass *uc)
{
struct uclass_driver *uc_drv;
struct udevice *dev;
int ret;
/*
* We cannot use list_for_each_entry_safe() here. If a device in this
* uclass has a child device also in this uclass, it will be also be
* unbound (by the recursion in the call to device_unbind() below).
* We can loop until the list is empty.
*/
while (!list_empty(&uc->dev_head)) {
dev = list_first_entry(&uc->dev_head, struct udevice,
uclass_node);
ret = device_remove(dev, DM_REMOVE_NORMAL | DM_REMOVE_NO_PD);
if (ret)
return log_msg_ret("remove", ret);
ret = device_unbind(dev);
if (ret)
return log_msg_ret("unbind", ret);
}
uc_drv = uc->uc_drv;
if (uc_drv->destroy)
uc_drv->destroy(uc);
list_del(&uc->sibling_node);
if (uc_drv->priv_auto)
free(uclass_get_priv(uc));
free(uc);
return 0;
}
int uclass_get(enum uclass_id id, struct uclass **ucp)
{
struct uclass *uc;
/* Immediately fail if driver model is not set up */
if (!gd->uclass_root)
return -EDEADLK;
*ucp = NULL;
uc = uclass_find(id);
if (!uc) {
if (CONFIG_IS_ENABLED(OF_PLATDATA_INST))
return -ENOENT;
return uclass_add(id, ucp);
}
*ucp = uc;
return 0;
}
const char *uclass_get_name(enum uclass_id id)
{
struct uclass *uc;
if (uclass_get(id, &uc))
return NULL;
return uc->uc_drv->name;
}
void *uclass_get_priv(const struct uclass *uc)
{
return uc->priv_;
}
void uclass_set_priv(struct uclass *uc, void *priv)
{
uc->priv_ = priv;
}
enum uclass_id uclass_get_by_name(const char *name)
{
int i;
for (i = 0; i < UCLASS_COUNT; i++) {
struct uclass_driver *uc_drv = lists_uclass_lookup(i);
if (uc_drv && !strcmp(uc_drv->name, name))
return i;
}
return UCLASS_INVALID;
}
int dev_get_uclass_index(struct udevice *dev, struct uclass **ucp)
{
struct udevice *iter;
struct uclass *uc = dev->uclass;
int i = 0;
if (list_empty(&uc->dev_head))
return -ENODEV;
uclass_foreach_dev(iter, uc) {
if (iter == dev) {
if (ucp)
*ucp = uc;
return i;
}
i++;
}
return -ENODEV;
}
int uclass_find_device(enum uclass_id id, int index, struct udevice **devp)
{
struct uclass *uc;
struct udevice *dev;
int ret;
*devp = NULL;
ret = uclass_get(id, &uc);
if (ret)
return ret;
if (list_empty(&uc->dev_head))
return -ENODEV;
uclass_foreach_dev(dev, uc) {
if (!index--) {
*devp = dev;
return 0;
}
}
return -ENODEV;
}
int uclass_find_first_device(enum uclass_id id, struct udevice **devp)
{
struct uclass *uc;
int ret;
*devp = NULL;
ret = uclass_get(id, &uc);
if (ret)
return ret;
if (list_empty(&uc->dev_head))
return 0;
*devp = list_first_entry(&uc->dev_head, struct udevice, uclass_node);
return 0;
}
int uclass_find_next_device(struct udevice **devp)
{
struct udevice *dev = *devp;
*devp = NULL;
if (list_is_last(&dev->uclass_node, &dev->uclass->dev_head))
return 0;
*devp = list_entry(dev->uclass_node.next, struct udevice, uclass_node);
return 0;
}
int uclass_find_device_by_name(enum uclass_id id, const char *name,
struct udevice **devp)
{
struct uclass *uc;
struct udevice *dev;
int ret;
*devp = NULL;
if (!name)
return -EINVAL;
ret = uclass_get(id, &uc);
if (ret)
return ret;
uclass_foreach_dev(dev, uc) {
if (!strcmp(dev->name, name)) {
*devp = dev;
return 0;
}
}
return -ENODEV;
}
int uclass_find_next_free_seq(struct uclass *uc)
{
struct udevice *dev;
int max = -1;
/* If using aliases, start with the highest alias value */
if (CONFIG_IS_ENABLED(DM_SEQ_ALIAS) &&
(uc->uc_drv->flags & DM_UC_FLAG_SEQ_ALIAS))
max = dev_read_alias_highest_id(uc->uc_drv->name);
/* Avoid conflict with existing devices */
list_for_each_entry(dev, &uc->dev_head, uclass_node) {
if (dev->seq_ > max)
max = dev->seq_;
}
/*
* At this point, max will be -1 if there are no existing aliases or
* devices
*/
return max + 1;
}
int uclass_find_device_by_seq(enum uclass_id id, int seq, struct udevice **devp)
{
struct uclass *uc;
struct udevice *dev;
int ret;
*devp = NULL;
log_debug("%d\n", seq);
if (seq == -1)
return -ENODEV;
ret = uclass_get(id, &uc);
if (ret)
return ret;
uclass_foreach_dev(dev, uc) {
log_debug(" - %d '%s'\n", dev->seq_, dev->name);
if (dev->seq_ == seq) {
*devp = dev;
log_debug(" - found\n");
return 0;
}
}
log_debug(" - not found\n");
return -ENODEV;
}
int uclass_find_device_by_of_offset(enum uclass_id id, int node,
struct udevice **devp)
{
struct uclass *uc;
struct udevice *dev;
int ret;
*devp = NULL;
if (node < 0)
return -ENODEV;
ret = uclass_get(id, &uc);
if (ret)
return ret;
uclass_foreach_dev(dev, uc) {
if (dev_of_offset(dev) == node) {
*devp = dev;
return 0;
}
}
return -ENODEV;
}
int uclass_find_device_by_ofnode(enum uclass_id id, ofnode node,
struct udevice **devp)
{
struct uclass *uc;
struct udevice *dev;
int ret;
log(LOGC_DM, LOGL_DEBUG, "Looking for %s\n", ofnode_get_name(node));
*devp = NULL;
if (!ofnode_valid(node))
return -ENODEV;
ret = uclass_get(id, &uc);
if (ret)
return ret;
uclass_foreach_dev(dev, uc) {
log(LOGC_DM, LOGL_DEBUG_CONTENT, " - checking %s\n",
dev->name);
if (ofnode_equal(dev_ofnode(dev), node)) {
*devp = dev;
goto done;
}
}
ret = -ENODEV;
done:
log(LOGC_DM, LOGL_DEBUG, " - result for %s: %s (ret=%d)\n",
ofnode_get_name(node), *devp ? (*devp)->name : "(none)", ret);
return ret;
}
#if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)
int uclass_find_device_by_phandle(enum uclass_id id, struct udevice *parent,
const char *name, struct udevice **devp)
{
struct udevice *dev;
struct uclass *uc;
int find_phandle;
int ret;
*devp = NULL;
find_phandle = dev_read_u32_default(parent, name, -1);
if (find_phandle <= 0)
return -ENOENT;
ret = uclass_get(id, &uc);
if (ret)
return ret;
uclass_foreach_dev(dev, uc) {
uint phandle;
phandle = dev_read_phandle(dev);
if (phandle == find_phandle) {
*devp = dev;
return 0;
}
}
return -ENODEV;
}
#endif
int uclass_get_device_by_driver(enum uclass_id id,
const struct driver *find_drv,
struct udevice **devp)
{
struct udevice *dev;
struct uclass *uc;
int ret;
ret = uclass_get(id, &uc);
if (ret)
return ret;
uclass_foreach_dev(dev, uc) {
if (dev->driver == find_drv)
return uclass_get_device_tail(dev, 0, devp);
}
return -ENODEV;
}
int uclass_get_device_tail(struct udevice *dev, int ret, struct udevice **devp)
{
if (ret)
return ret;
assert(dev);
ret = device_probe(dev);
if (ret)
return ret;
*devp = dev;
return 0;
}
int uclass_get_device(enum uclass_id id, int index, struct udevice **devp)
{
struct udevice *dev;
int ret;
*devp = NULL;
ret = uclass_find_device(id, index, &dev);
return uclass_get_device_tail(dev, ret, devp);
}
int uclass_get_device_by_name(enum uclass_id id, const char *name,
struct udevice **devp)
{
struct udevice *dev;
int ret;
*devp = NULL;
ret = uclass_find_device_by_name(id, name, &dev);
return uclass_get_device_tail(dev, ret, devp);
}
int uclass_get_device_by_seq(enum uclass_id id, int seq, struct udevice **devp)
{
struct udevice *dev;
int ret;
*devp = NULL;
ret = uclass_find_device_by_seq(id, seq, &dev);
return uclass_get_device_tail(dev, ret, devp);
}
int uclass_get_device_by_of_offset(enum uclass_id id, int node,
struct udevice **devp)
{
struct udevice *dev;
int ret;
*devp = NULL;
ret = uclass_find_device_by_of_offset(id, node, &dev);
return uclass_get_device_tail(dev, ret, devp);
}
int uclass_get_device_by_ofnode(enum uclass_id id, ofnode node,
struct udevice **devp)
{
struct udevice *dev;
int ret;
log(LOGC_DM, LOGL_DEBUG, "Looking for %s\n", ofnode_get_name(node));
*devp = NULL;
ret = uclass_find_device_by_ofnode(id, node, &dev);
log(LOGC_DM, LOGL_DEBUG, " - result for %s: %s (ret=%d)\n",
ofnode_get_name(node), dev ? dev->name : "(none)", ret);
return uclass_get_device_tail(dev, ret, devp);
}
#if CONFIG_IS_ENABLED(OF_CONTROL)
int uclass_get_device_by_phandle_id(enum uclass_id id, uint phandle_id,
struct udevice **devp)
{
struct udevice *dev;
struct uclass *uc;
int ret;
*devp = NULL;
ret = uclass_get(id, &uc);
if (ret)
return ret;
uclass_foreach_dev(dev, uc) {
uint phandle;
phandle = dev_read_phandle(dev);
if (phandle == phandle_id) {
*devp = dev;
return uclass_get_device_tail(dev, ret, devp);
}
}
return -ENODEV;
}
int uclass_get_device_by_phandle(enum uclass_id id, struct udevice *parent,
const char *name, struct udevice **devp)
{
struct udevice *dev;
int ret;
*devp = NULL;
ret = uclass_find_device_by_phandle(id, parent, name, &dev);
return uclass_get_device_tail(dev, ret, devp);
}
#endif
int uclass_first_device(enum uclass_id id, struct udevice **devp)
{
struct udevice *dev;
int ret;
*devp = NULL;
ret = uclass_find_first_device(id, &dev);
if (!dev)
return 0;
return uclass_get_device_tail(dev, ret, devp);
}
int uclass_first_device_err(enum uclass_id id, struct udevice **devp)
{
int ret;
ret = uclass_first_device(id, devp);
if (ret)
return ret;
else if (!*devp)
return -ENODEV;
return 0;
}
int uclass_next_device(struct udevice **devp)
{
struct udevice *dev = *devp;
int ret;
*devp = NULL;
ret = uclass_find_next_device(&dev);
if (!dev)
return 0;
return uclass_get_device_tail(dev, ret, devp);
}
int uclass_next_device_err(struct udevice **devp)
{
int ret;
ret = uclass_next_device(devp);
if (ret)
return ret;
else if (!*devp)
return -ENODEV;
return 0;
}
int uclass_first_device_check(enum uclass_id id, struct udevice **devp)
{
int ret;
*devp = NULL;
ret = uclass_find_first_device(id, devp);
if (ret)
return ret;
if (!*devp)
return 0;
return device_probe(*devp);
}
int uclass_next_device_check(struct udevice **devp)
{
int ret;
ret = uclass_find_next_device(devp);
if (ret)
return ret;
if (!*devp)
return 0;
return device_probe(*devp);
}
int uclass_first_device_drvdata(enum uclass_id id, ulong driver_data,
struct udevice **devp)
{
struct udevice *dev;
struct uclass *uc;
uclass_id_foreach_dev(id, dev, uc) {
if (dev_get_driver_data(dev) == driver_data) {
*devp = dev;
return device_probe(dev);
}
}
return -ENODEV;
}
int uclass_bind_device(struct udevice *dev)
{
struct uclass *uc;
int ret;
uc = dev->uclass;
list_add_tail(&dev->uclass_node, &uc->dev_head);
if (dev->parent) {
struct uclass_driver *uc_drv = dev->parent->uclass->uc_drv;
if (uc_drv->child_post_bind) {
ret = uc_drv->child_post_bind(dev);
if (ret)
goto err;
}
}
return 0;
err:
/* There is no need to undo the parent's post_bind call */
list_del(&dev->uclass_node);
return ret;
}
#if CONFIG_IS_ENABLED(DM_DEVICE_REMOVE)
int uclass_unbind_device(struct udevice *dev)
{
struct uclass *uc;
int ret;
uc = dev->uclass;
if (uc->uc_drv->pre_unbind) {
ret = uc->uc_drv->pre_unbind(dev);
if (ret)
return ret;
}
list_del(&dev->uclass_node);
return 0;
}
#endif
int uclass_pre_probe_device(struct udevice *dev)
{
struct uclass_driver *uc_drv;
int ret;
uc_drv = dev->uclass->uc_drv;
if (uc_drv->pre_probe) {
ret = uc_drv->pre_probe(dev);
if (ret)
return ret;
}
if (!dev->parent)
return 0;
uc_drv = dev->parent->uclass->uc_drv;
if (uc_drv->child_pre_probe) {
ret = uc_drv->child_pre_probe(dev);
if (ret)
return ret;
}
return 0;
}
int uclass_post_probe_device(struct udevice *dev)
{
struct uclass_driver *uc_drv;
int ret;
if (dev->parent) {
uc_drv = dev->parent->uclass->uc_drv;
if (uc_drv->child_post_probe) {
ret = uc_drv->child_post_probe(dev);
if (ret)
return ret;
}
}
uc_drv = dev->uclass->uc_drv;
if (uc_drv->post_probe) {
ret = uc_drv->post_probe(dev);
if (ret)
return ret;
}
return 0;
}
#if CONFIG_IS_ENABLED(DM_DEVICE_REMOVE)
int uclass_pre_remove_device(struct udevice *dev)
{
struct uclass *uc;
int ret;
uc = dev->uclass;
if (uc->uc_drv->pre_remove) {
ret = uc->uc_drv->pre_remove(dev);
if (ret)
return ret;
}
return 0;
}
#endif
int uclass_probe_all(enum uclass_id id)
{
struct udevice *dev;
int ret;
ret = uclass_first_device(id, &dev);
if (ret || !dev)
return ret;
/* Scanning uclass to probe all devices */
while (dev) {
ret = uclass_next_device(&dev);
if (ret)
return ret;
}
return 0;
}
UCLASS_DRIVER(nop) = {
.id = UCLASS_NOP,
.name = "nop",
};