linux-stable/drivers/interconnect/qcom/icc-rpmh.c
Johan Hovold 74240a5beb interconnect: qcom: rpmh: fix registration race
The current interconnect provider registration interface is inherently
racy as nodes are not added until the after adding the provider. This
can specifically cause racing DT lookups to fail.

Switch to using the new API where the provider is not registered until
after it has been fully initialised.

Fixes: 976daac4a1 ("interconnect: qcom: Consolidate interconnect RPMh support")
Cc: stable@vger.kernel.org      # 5.7
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Link: https://lore.kernel.org/r/20230306075651.2449-11-johan+linaro@kernel.org
Signed-off-by: Georgi Djakov <djakov@kernel.org>
2023-03-13 21:13:48 +02:00

268 lines
5.9 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2020, The Linux Foundation. All rights reserved.
*/
#include <linux/interconnect.h>
#include <linux/interconnect-provider.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/slab.h>
#include "bcm-voter.h"
#include "icc-common.h"
#include "icc-rpmh.h"
/**
* qcom_icc_pre_aggregate - cleans up stale values from prior icc_set
* @node: icc node to operate on
*/
void qcom_icc_pre_aggregate(struct icc_node *node)
{
size_t i;
struct qcom_icc_node *qn;
struct qcom_icc_provider *qp;
qn = node->data;
qp = to_qcom_provider(node->provider);
for (i = 0; i < QCOM_ICC_NUM_BUCKETS; i++) {
qn->sum_avg[i] = 0;
qn->max_peak[i] = 0;
}
for (i = 0; i < qn->num_bcms; i++)
qcom_icc_bcm_voter_add(qp->voter, qn->bcms[i]);
}
EXPORT_SYMBOL_GPL(qcom_icc_pre_aggregate);
/**
* qcom_icc_aggregate - aggregate bw for buckets indicated by tag
* @node: node to aggregate
* @tag: tag to indicate which buckets to aggregate
* @avg_bw: new bw to sum aggregate
* @peak_bw: new bw to max aggregate
* @agg_avg: existing aggregate avg bw val
* @agg_peak: existing aggregate peak bw val
*/
int qcom_icc_aggregate(struct icc_node *node, u32 tag, u32 avg_bw,
u32 peak_bw, u32 *agg_avg, u32 *agg_peak)
{
size_t i;
struct qcom_icc_node *qn;
qn = node->data;
if (!tag)
tag = QCOM_ICC_TAG_ALWAYS;
for (i = 0; i < QCOM_ICC_NUM_BUCKETS; i++) {
if (tag & BIT(i)) {
qn->sum_avg[i] += avg_bw;
qn->max_peak[i] = max_t(u32, qn->max_peak[i], peak_bw);
}
if (node->init_avg || node->init_peak) {
qn->sum_avg[i] = max_t(u64, qn->sum_avg[i], node->init_avg);
qn->max_peak[i] = max_t(u64, qn->max_peak[i], node->init_peak);
}
}
*agg_avg += avg_bw;
*agg_peak = max_t(u32, *agg_peak, peak_bw);
return 0;
}
EXPORT_SYMBOL_GPL(qcom_icc_aggregate);
/**
* qcom_icc_set - set the constraints based on path
* @src: source node for the path to set constraints on
* @dst: destination node for the path to set constraints on
*
* Return: 0 on success, or an error code otherwise
*/
int qcom_icc_set(struct icc_node *src, struct icc_node *dst)
{
struct qcom_icc_provider *qp;
struct icc_node *node;
if (!src)
node = dst;
else
node = src;
qp = to_qcom_provider(node->provider);
qcom_icc_bcm_voter_commit(qp->voter);
return 0;
}
EXPORT_SYMBOL_GPL(qcom_icc_set);
/**
* qcom_icc_bcm_init - populates bcm aux data and connect qnodes
* @bcm: bcm to be initialized
* @dev: associated provider device
*
* Return: 0 on success, or an error code otherwise
*/
int qcom_icc_bcm_init(struct qcom_icc_bcm *bcm, struct device *dev)
{
struct qcom_icc_node *qn;
const struct bcm_db *data;
size_t data_count;
int i;
/* BCM is already initialised*/
if (bcm->addr)
return 0;
bcm->addr = cmd_db_read_addr(bcm->name);
if (!bcm->addr) {
dev_err(dev, "%s could not find RPMh address\n",
bcm->name);
return -EINVAL;
}
data = cmd_db_read_aux_data(bcm->name, &data_count);
if (IS_ERR(data)) {
dev_err(dev, "%s command db read error (%ld)\n",
bcm->name, PTR_ERR(data));
return PTR_ERR(data);
}
if (!data_count) {
dev_err(dev, "%s command db missing or partial aux data\n",
bcm->name);
return -EINVAL;
}
bcm->aux_data.unit = le32_to_cpu(data->unit);
bcm->aux_data.width = le16_to_cpu(data->width);
bcm->aux_data.vcd = data->vcd;
bcm->aux_data.reserved = data->reserved;
INIT_LIST_HEAD(&bcm->list);
INIT_LIST_HEAD(&bcm->ws_list);
if (!bcm->vote_scale)
bcm->vote_scale = 1000;
/* Link Qnodes to their respective BCMs */
for (i = 0; i < bcm->num_nodes; i++) {
qn = bcm->nodes[i];
qn->bcms[qn->num_bcms] = bcm;
qn->num_bcms++;
}
return 0;
}
EXPORT_SYMBOL_GPL(qcom_icc_bcm_init);
int qcom_icc_rpmh_probe(struct platform_device *pdev)
{
const struct qcom_icc_desc *desc;
struct device *dev = &pdev->dev;
struct icc_onecell_data *data;
struct icc_provider *provider;
struct qcom_icc_node * const *qnodes, *qn;
struct qcom_icc_provider *qp;
struct icc_node *node;
size_t num_nodes, i, j;
int ret;
desc = of_device_get_match_data(dev);
if (!desc)
return -EINVAL;
qnodes = desc->nodes;
num_nodes = desc->num_nodes;
qp = devm_kzalloc(dev, sizeof(*qp), GFP_KERNEL);
if (!qp)
return -ENOMEM;
data = devm_kzalloc(dev, struct_size(data, nodes, num_nodes), GFP_KERNEL);
if (!data)
return -ENOMEM;
provider = &qp->provider;
provider->dev = dev;
provider->set = qcom_icc_set;
provider->pre_aggregate = qcom_icc_pre_aggregate;
provider->aggregate = qcom_icc_aggregate;
provider->xlate_extended = qcom_icc_xlate_extended;
provider->data = data;
icc_provider_init(provider);
qp->dev = dev;
qp->bcms = desc->bcms;
qp->num_bcms = desc->num_bcms;
qp->voter = of_bcm_voter_get(qp->dev, NULL);
if (IS_ERR(qp->voter))
return PTR_ERR(qp->voter);
for (i = 0; i < qp->num_bcms; i++)
qcom_icc_bcm_init(qp->bcms[i], dev);
for (i = 0; i < num_nodes; i++) {
qn = qnodes[i];
if (!qn)
continue;
node = icc_node_create(qn->id);
if (IS_ERR(node)) {
ret = PTR_ERR(node);
goto err_remove_nodes;
}
node->name = qn->name;
node->data = qn;
icc_node_add(node, provider);
for (j = 0; j < qn->num_links; j++)
icc_link_create(node, qn->links[j]);
data->nodes[i] = node;
}
data->num_nodes = num_nodes;
ret = icc_provider_register(provider);
if (ret)
goto err_remove_nodes;
platform_set_drvdata(pdev, qp);
/* Populate child NoC devices if any */
if (of_get_child_count(dev->of_node) > 0) {
ret = of_platform_populate(dev->of_node, NULL, NULL, dev);
if (ret)
goto err_deregister_provider;
}
return 0;
err_deregister_provider:
icc_provider_deregister(provider);
err_remove_nodes:
icc_nodes_remove(provider);
return ret;
}
EXPORT_SYMBOL_GPL(qcom_icc_rpmh_probe);
int qcom_icc_rpmh_remove(struct platform_device *pdev)
{
struct qcom_icc_provider *qp = platform_get_drvdata(pdev);
icc_provider_deregister(&qp->provider);
icc_nodes_remove(&qp->provider);
return 0;
}
EXPORT_SYMBOL_GPL(qcom_icc_rpmh_remove);
MODULE_LICENSE("GPL v2");