// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2020-2021, The Linux Foundation. All rights reserved.
*/
#include <asm/div64.h>
#include <linux/interconnect-provider.h>
#include <linux/list_sort.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <soc/qcom/rpmh.h>
#include <soc/qcom/tcs.h>
#include "bcm-voter.h"
#include "icc-rpmh.h"
static LIST_HEAD(bcm_voters);
static DEFINE_MUTEX(bcm_voter_lock);
/**
* struct bcm_voter - Bus Clock Manager voter
* @dev: reference to the device that communicates with the BCM
* @np: reference to the device node to match bcm voters
* @lock: mutex to protect commit and wake/sleep lists in the voter
* @commit_list: list containing bcms to be committed to hardware
* @ws_list: list containing bcms that have different wake/sleep votes
* @voter_node: list of bcm voters
* @tcs_wait: mask for which buckets require TCS completion
*/
struct bcm_voter {
struct device *dev;
struct device_node *np;
struct mutex lock;
struct list_head commit_list;
struct list_head ws_list;
struct list_head voter_node;
u32 tcs_wait;
};
static int cmp_vcd(void *priv, const struct list_head *a, const struct list_head *b)
{
const struct qcom_icc_bcm *bcm_a = list_entry(a, struct qcom_icc_bcm, list);
const struct qcom_icc_bcm *bcm_b = list_entry(b, struct qcom_icc_bcm, list);
return bcm_a->aux_data.vcd - bcm_b->aux_data.vcd;
}
static u64 bcm_div(u64 num, u32 base)
{
/* Ensure that small votes aren't lost. */
if (num && num < base)
return 1;
do_div(num, base);
return num;
}
/* BCMs with enable_mask use one-hot-encoding for on/off signaling */
static void bcm_aggregate_mask(struct qcom_icc_bcm *bcm)
{
struct qcom_icc_node *node;
int bucket, i;
for (bucket = 0; bucket < QCOM_ICC_NUM_BUCKETS; bucket++) {
bcm->vote_x[bucket] = 0;
bcm->vote_y[bucket] = 0;
for (i = 0; i < bcm->num_nodes; i++) {
node = bcm->nodes[i];
/* If any vote in this bucket exists, keep the BCM enabled */
if (node->sum_avg[bucket] || node->max_peak[bucket]) {
bcm->vote_x[bucket] = 0;
bcm->vote_y[bucket] = bcm->enable_mask;
break;
}
}
}
if (bcm->keepalive) {
bcm->vote_x[QCOM_ICC_BUCKET_AMC] = bcm->enable_mask;
bcm->vote_x[QCOM_ICC_BUCKET_WAKE] = bcm->enable_mask;
bcm->vote_y[QCOM_ICC_BUCKET_AMC] = bcm->enable_mask;
bcm->vote_y[QCOM_ICC_BUCKET_WAKE] = bcm->enable_mask;
}
}
static void bcm_aggregate(struct qcom_icc_bcm *bcm)
{
struct qcom_icc_node *node;
size_t i, bucket;
u64 agg_avg[QCOM_ICC_NUM_BUCKETS] = {0};
u64 agg_peak[QCOM_ICC_NUM_BUCKETS] = {0};
u64 temp;
for (bucket = 0; bucket < QCOM_ICC_NUM_BUCKETS; bucket++) {
for (i = 0; i < bcm->num_nodes; i++) {
node = bcm->nodes[i];
temp = bcm_div(node->sum_avg[bucket] * bcm->aux_data.width,
node->buswidth * node->channels);
agg_avg[bucket] = max(agg_avg[bucket], temp);
temp = bcm_div(node->max_peak[bucket] * bcm->aux_data.width,
node->buswidth);
agg_peak[bucket] = max(agg_peak[bucket], temp);
}
temp = agg_avg[bucket] * bcm->vote_scale;
bcm->vote_x[bucket] = bcm_div(temp, bcm->aux_data.unit);
temp = agg_peak[bucket] * bcm->vote_scale;
bcm->vote_y[bucket] = bcm_div(temp, bcm->aux_data.unit);
}
if (bcm->keepalive && bcm->vote_x[QCOM_ICC_BUCKET_AMC] == 0 &&
bcm->vote_y[QCOM_ICC_BUCKET_AMC] == 0) {
bcm->vote_x[QCOM_ICC_BUCKET_AMC] = 1;
bcm->vote_x[QCOM_ICC_BUCKET_WAKE] = 1;
bcm->vote_y[QCOM_ICC_BUCKET_AMC] = 1;
bcm->vote_y[QCOM_ICC_BUCKET_WAKE] = 1;
}
}
static inline void tcs_cmd_gen(struct tcs_cmd *cmd, u64 vote_x, u64 vote_y,
u32 addr, bool commit, bool wait)
{
bool valid = true;
if (!cmd)
return;
memset(cmd, 0, sizeof(*cmd));
if (vote_x == 0 && vote_y == 0)
valid = false;
if (vote_x > BCM_TCS_CMD_VOTE_MASK)
vote_x = BCM_TCS_CMD_VOTE_MASK;
if (vote_y > BCM_TCS_CMD_VOTE_MASK)
vote_y = BCM_TCS_CMD_VOTE_MASK;
cmd->addr = addr;
cmd->data = BCM_TCS_CMD(commit, valid, vote_x, vote_y);
/*
* Set the wait for completion flag on command that need to be completed
* before the next command.
*/
cmd->wait = wait;
}
static void tcs_list_gen(struct bcm_voter *voter, int bucket,
struct tcs_cmd tcs_list[MAX_VCD],
int n[MAX_VCD + 1])
{
struct list_head *bcm_list = &voter->commit_list;
struct qcom_icc_bcm *bcm;
bool commit, wait;
size_t idx = 0, batch = 0, cur_vcd_size = 0;
memset(n, 0, sizeof(int) * (MAX_VCD + 1));
list_for_each_entry(bcm, bcm_list, list) {
commit = false;
cur_vcd_size++;
if ((list_is_last(&bcm->list, bcm_list)) ||
bcm->aux_data.vcd != list_next_entry(bcm, list)->aux_data.vcd) {
commit = true;
cur_vcd_size = 0;
}
wait = commit && (voter->tcs_wait & BIT(bucket));
tcs_cmd_gen(&tcs_list[idx], bcm->vote_x[bucket],
bcm->vote_y[bucket], bcm->addr, commit, wait);
idx++;
n[batch]++;
/*
* Batch the BCMs in such a way that we do not split them in
* multiple payloads when they are under the same VCD. This is
* to ensure that every BCM is committed since we only set the
* commit bit on the last BCM request of every VCD.
*/
if (n[batch] >= MAX_RPMH_PAYLOAD) {
if (!commit) {
n[batch] -= cur_vcd_size;
n[batch + 1] = cur_vcd_size;
}
batch++;
}
}
}
/**
* of_bcm_voter_get - gets a bcm voter handle from DT node
* @dev: device pointer for the consumer device
* @name: name for the bcm voter device
*
* This function will match a device_node pointer for the phandle
* specified in the device DT and return a bcm_voter handle on success.
*
* Returns bcm_voter pointer or ERR_PTR() on error. EPROBE_DEFER is returned
* when matching bcm voter is yet to be found.
*/
struct bcm_voter *of_bcm_voter_get(struct device *dev, const char *name)
{
struct bcm_voter *voter = ERR_PTR(-EPROBE_DEFER);
struct bcm_voter *temp;
struct device_node *np, *node;
int idx = 0;
if (!dev || !dev->of_node)
return ERR_PTR(-ENODEV);
np = dev->of_node;
if (name) {
idx = of_property_match_string(np, "qcom,bcm-voter-names", name);
if (idx < 0)
return ERR_PTR(idx);
}
node = of_parse_phandle(np, "qcom,bcm-voters", idx);
mutex_lock(&bcm_voter_lock);
list_for_each_entry(temp, &bcm_voters, voter_node) {
if (temp->np == node) {
voter = temp;
break;
}
}
mutex_unlock(&bcm_voter_lock);
of_node_put(node);
return voter;
}
EXPORT_SYMBOL_GPL(of_bcm_voter_get);
/**
* qcom_icc_bcm_voter_add - queues up the bcm nodes that require updates
* @voter: voter that the bcms are being added to
* @bcm: bcm to add to the commit and wake sleep list
*/
void qcom_icc_bcm_voter_add(struct bcm_voter *voter, struct qcom_icc_bcm *bcm)
{
if (!voter)
return;
mutex_lock(&voter->lock);
if (list_empty(&bcm->list))
list_add_tail(&bcm->list, &voter->commit_list);
if (list_empty(&bcm->ws_list))
list_add_tail(&bcm->ws_list, &voter->ws_list);
mutex_unlock(&voter->lock);
}
EXPORT_SYMBOL_GPL(qcom_icc_bcm_voter_add);
/**
* qcom_icc_bcm_voter_commit - generates and commits tcs cmds based on bcms
* @voter: voter that needs flushing
*
* This function generates a set of AMC commands and flushes to the BCM device
* associated with the voter. It conditionally generate WAKE and SLEEP commands
* based on deltas between WAKE/SLEEP requirements. The ws_list persists
* through multiple commit requests and bcm nodes are removed only when the
* requirements for WAKE matches SLEEP.
*
* Returns 0 on success, or an appropriate error code otherwise.
*/
int qcom_icc_bcm_voter_commit(struct bcm_voter *voter)
{
struct qcom_icc_bcm *bcm;
struct qcom_icc_bcm *bcm_tmp;
int commit_idx[MAX_VCD + 1];
struct tcs_cmd cmds[MAX_BCMS];
int ret = 0;
if (!voter)
return 0;
mutex_lock(&voter->lock);
list_for_each_entry(bcm, &voter->commit_list, list) {
if (bcm->enable_mask)
bcm_aggregate_mask(bcm);
else
bcm_aggregate(bcm);
}
/*
* Pre sort the BCMs based on VCD for ease of generating a command list
* that groups the BCMs with the same VCD together. VCDs are numbered
* with lowest being the most expensive time wise, ensuring that
* those commands are being sent the earliest in the queue. This needs
* to be sorted every commit since we can't guarantee the order in which
* the BCMs are added to the list.
*/
list_sort(NULL, &voter->commit_list, cmp_vcd);
/*
* Construct the command list based on a pre ordered list of BCMs
* based on VCD.
*/
tcs_list_gen(voter, QCOM_ICC_BUCKET_AMC, cmds, commit_idx);
if (!commit_idx[0])
goto out;
rpmh_invalidate(voter->dev);
ret = rpmh_write_batch(voter->dev, RPMH_ACTIVE_ONLY_STATE,
cmds, commit_idx);
if (ret) {
pr_err("Error sending AMC RPMH requests (%d)\n", ret);
goto out;
}
list_for_each_entry_safe(bcm, bcm_tmp, &voter->commit_list, list)
list_del_init(&bcm->list);
list_for_each_entry_safe(bcm, bcm_tmp, &voter->ws_list, ws_list) {
/*
* Only generate WAKE and SLEEP commands if a resource's
* requirements change as the execution environment transitions
* between different power states.
*/
if (bcm->vote_x[QCOM_ICC_BUCKET_WAKE] !=
bcm->vote_x[QCOM_ICC_BUCKET_SLEEP] ||
bcm->vote_y[QCOM_ICC_BUCKET_WAKE] !=
bcm->vote_y[QCOM_ICC_BUCKET_SLEEP])
list_add_tail(&bcm->list, &voter->commit_list);
else
list_del_init(&bcm->ws_list);
}
if (list_empty(&voter->commit_list))
goto out;
list_sort(NULL, &voter->commit_list, cmp_vcd);
tcs_list_gen(voter, QCOM_ICC_BUCKET_WAKE, cmds, commit_idx);
ret = rpmh_write_batch(voter->dev, RPMH_WAKE_ONLY_STATE, cmds, commit_idx);
if (ret) {
pr_err("Error sending WAKE RPMH requests (%d)\n", ret);
goto out;
}
tcs_list_gen(voter, QCOM_ICC_BUCKET_SLEEP, cmds, commit_idx);
ret = rpmh_write_batch(voter->dev, RPMH_SLEEP_STATE, cmds, commit_idx);
if (ret) {
pr_err("Error sending SLEEP RPMH requests (%d)\n", ret);
goto out;
}
out:
list_for_each_entry_safe(bcm, bcm_tmp, &voter->commit_list, list)
list_del_init(&bcm->list);
mutex_unlock(&voter->lock);
return ret;
}
EXPORT_SYMBOL_GPL(qcom_icc_bcm_voter_commit);
static int qcom_icc_bcm_voter_probe(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
struct bcm_voter *voter;
voter = devm_kzalloc(&pdev->dev, sizeof(*voter), GFP_KERNEL);
if (!voter)
return -ENOMEM;
voter->dev = &pdev->dev;
voter->np = np;
if (of_property_read_u32(np, "qcom,tcs-wait", &voter->tcs_wait))
voter->tcs_wait = QCOM_ICC_TAG_ACTIVE_ONLY;
mutex_init(&voter->lock);
INIT_LIST_HEAD(&voter->commit_list);
INIT_LIST_HEAD(&voter->ws_list);
mutex_lock(&bcm_voter_lock);
list_add_tail(&voter->voter_node, &bcm_voters);
mutex_unlock(&bcm_voter_lock);
return 0;
}
static const struct of_device_id bcm_voter_of_match[] = {
{ .compatible = "qcom,bcm-voter" },
{ }
};
MODULE_DEVICE_TABLE(of, bcm_voter_of_match);
static struct platform_driver qcom_icc_bcm_voter_driver = {
.probe = qcom_icc_bcm_voter_probe,
.driver = {
.name = "bcm_voter",
.of_match_table = bcm_voter_of_match,
},
};
module_platform_driver(qcom_icc_bcm_voter_driver);
MODULE_AUTHOR("David Dai <[email protected]>");
MODULE_DESCRIPTION("Qualcomm BCM Voter interconnect driver");
MODULE_LICENSE("GPL v2");
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