Re: [PATCH v2 4/6] interconnect: qcom: Consolidate interconnect RPMh support

Sibi Sankar
2020-02-09T17:58:53Z

Hey Evan,
I am taking a stab at re-spinning the
series. Apart the issues you've identified
I added a few more to the list.

On 2020-02-04 23:52, Evan Green wrote:
> On Thu, Jan 9, 2020 at 8:33 PM David Dai <daidavid1@codeaurora.org>
> wrote:
>>
>> Add bcm voter driver and add support for RPMh specific interconnect
>> providers
>> which implements the set and aggregate functionalities that translates
>> bandwidth requests into RPMh messages. These modules provide a common
>> set of
>> functionalities for all Qualcomm RPMh based interconnect providers and
>> should help reduce code duplication when adding new providers.
>>
>> Signed-off-by: David Dai <daidavid1@codeaurora.org>
>
> This was a little tough to wrap my head around, but then I understood
> that most of it was a copy of functions from sdm845.c, which are later
> deleted in patch 5 when sdm845.c uses the bcm-voter driver.
>
>> ---
>> drivers/interconnect/qcom/Kconfig | 8 +
>> drivers/interconnect/qcom/Makefile | 4 +
>> drivers/interconnect/qcom/bcm-voter.c | 363
>> ++++++++++++++++++++++++++++++++++
>> drivers/interconnect/qcom/bcm-voter.h | 28 +++
>> drivers/interconnect/qcom/icc-rpmh.c | 158 +++++++++++++++
>> drivers/interconnect/qcom/icc-rpmh.h | 151 ++++++++++++++
>> 6 files changed, 712 insertions(+)
>> create mode 100644 drivers/interconnect/qcom/bcm-voter.c
>> create mode 100644 drivers/interconnect/qcom/bcm-voter.h
>> create mode 100644 drivers/interconnect/qcom/icc-rpmh.c
>> create mode 100644 drivers/interconnect/qcom/icc-rpmh.h
>>
>> diff --git a/drivers/interconnect/qcom/Kconfig
>> b/drivers/interconnect/qcom/Kconfig
>> index 2f9304d..cd100a4 100644
>> --- a/drivers/interconnect/qcom/Kconfig
>> +++ b/drivers/interconnect/qcom/Kconfig
>> @@ -5,6 +5,9 @@ config INTERCONNECT_QCOM
>> help
>> Support for Qualcomm's Network-on-Chip interconnect
>> hardware.
>>
>> +config INTERCONNECT_QCOM_BCM_VOTER
>> + tristate

Looks like the dependencies are
not captured.

>> +
>> config INTERCONNECT_QCOM_MSM8974
>> tristate "Qualcomm MSM8974 interconnect driver"
>> depends on INTERCONNECT_QCOM
>> @@ -23,10 +26,15 @@ config INTERCONNECT_QCOM_QCS404
>> This is a driver for the Qualcomm Network-on-Chip on
>> qcs404-based
>> platforms.
>>
>> +config INTERCONNECT_QCOM_RPMH
>> + tristate

Looks like the dependencies are
not captured.

>> +
>> config INTERCONNECT_QCOM_SDM845
>> tristate "Qualcomm SDM845 interconnect driver"
>> depends on INTERCONNECT_QCOM
>> depends on (QCOM_RPMH && QCOM_COMMAND_DB && OF) ||
>> COMPILE_TEST
>> + select INTERCONNECT_QCOM_RPMH
>> + select INTERCONNECT_QCOM_BCM_VOTER
>> help
>> This is a driver for the Qualcomm Network-on-Chip on
>> sdm845-based
>> platforms.
>> diff --git a/drivers/interconnect/qcom/Makefile
>> b/drivers/interconnect/qcom/Makefile
>> index 9adf9e3..9317fa7 100644
>> --- a/drivers/interconnect/qcom/Makefile
>> +++ b/drivers/interconnect/qcom/Makefile
>> @@ -4,8 +4,12 @@ qnoc-msm8974-objs := msm8974.o
>> qnoc-qcs404-objs := qcs404.o
>> qnoc-sdm845-objs := sdm845.o
>> icc-smd-rpm-objs := smd-rpm.o
>> +icc-bcm-voter-objs := bcm-voter.o
>> +icc-rpmh-obj := icc-rpmh.o

nit: could be re-ordered

>>
>> +obj-$(CONFIG_INTERCONNECT_QCOM_BCM_VOTER) += icc-bcm-voter.o
>> obj-$(CONFIG_INTERCONNECT_QCOM_MSM8974) += qnoc-msm8974.o
>> obj-$(CONFIG_INTERCONNECT_QCOM_QCS404) += qnoc-qcs404.o
>> +obj-$(CONFIG_INTERCONNECT_QCOM_RPMH) += icc-rpmh.o
>> obj-$(CONFIG_INTERCONNECT_QCOM_SDM845) += qnoc-sdm845.o
>> obj-$(CONFIG_INTERCONNECT_QCOM_SMD_RPM) += icc-smd-rpm.o
>> diff --git a/drivers/interconnect/qcom/bcm-voter.c
>> b/drivers/interconnect/qcom/bcm-voter.c
>> new file mode 100644
>> index 0000000..a65680e
>> --- /dev/null
>> +++ b/drivers/interconnect/qcom/bcm-voter.c
>> @@ -0,0 +1,363 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * Copyright (c) 2019, The Linux Foundation. All rights reserved.
>> + *
>> + */
>> +#include <linux/interconnect-provider.h>
>> +#include <linux/list_sort.h>
>> +#include <linux/module.h>
>> +#include <linux/of.h>
>> +#include <linux/of_platform.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);
>
> Doesn't this need a lock?

yes this does need a 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
>> + */
>> +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;
>> +};
>> +
>> +static int cmp_vcd(void *priv, struct list_head *a, 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);
>> +
>> + if (bcm_a->aux_data.vcd < bcm_b->aux_data.vcd)
>> + return -1;
>> + else if (bcm_a->aux_data.vcd == bcm_b->aux_data.vcd)
>> + return 0;
>> + else
>> + return 1;
>> +}
>> +
>> +static void bcm_aggregate(struct qcom_icc_bcm *bcm)
>> +{
>> + 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++) {
>> + temp = bcm->nodes[i]->sum_avg[bucket] *
>> bcm->aux_data.width;
>> + do_div(temp, bcm->nodes[i]->buswidth *
>> bcm->nodes[i]->channels);
>> + agg_avg[bucket] = max(agg_avg[bucket], temp);
>> +
>> + temp = bcm->nodes[i]->max_peak[bucket] *
>> bcm->aux_data.width;
>> + do_div(temp, bcm->nodes[i]->buswidth);
>> + agg_peak[bucket] = max(agg_peak[bucket],
>> temp);
>> + }
>> +
>> + temp = agg_avg[bucket] * 1000ULL;
>> + do_div(temp, bcm->aux_data.unit);
>> + bcm->vote_x[bucket] = temp;
>> +
>> + temp = agg_peak[bucket] * 1000ULL;
>> + do_div(temp, bcm->aux_data.unit);
>> + bcm->vote_y[bucket] = temp;
>> + }
>> +
>> + 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 valid = true;
>> +
>> + if (!cmd)
>> + return;
>> +
>> + 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.
>> + */
>> + if (commit)
>> + cmd->wait = true;
>> +}
>> +
>> +static void tcs_list_gen(struct list_head *bcm_list, int bucket,
>> + struct tcs_cmd tcs_list[MAX_VCD],

tcs_list should be an array of
size MAX_BCMS.

>> + int n[MAX_VCD])
>
> "n" should really be MAX_VCD + 1 to guarantee that it's
> zero-terminated, otherwise rpmh_write_batch() could go nuts.

though the combination MAX_VCD,
MAX_BCMs and vcd info read back
from cmd_db for the bcms ensure that
situation does not occur, it does
make sense to have it MAX_VCD + 1.

>
>> +{
>> + struct qcom_icc_bcm *bcm;
>> + bool commit;
>> + size_t idx = 0, batch = 0, cur_vcd_size = 0;
>> +
>> + memset(n, 0, sizeof(int) * MAX_VCD);
>> +
>> + 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;
>> + }
>> + tcs_cmd_gen(&tcs_list[idx], bcm->vote_x[bucket],
>> + bcm->vote_y[bucket], bcm->addr, commit);
>> + 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;
>
> You lost what used to be a -= here to just an = during the copy from
> sdm845.c. How did that happen?
>
>> + 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);
>> +
>> + list_for_each_entry(temp, &bcm_voters, voter_node) {
>> + if (temp->np == node) {
>> + voter = temp;
>> + break;
>> + }
>> + }
>> +
>> + 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];
>> + 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)
>> + 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->commit_list, QCOM_ICC_BUCKET_AMC, cmds,
>> commit_idx);
>> +
>> + if (!commit_idx[0])
>> + goto out;
>> +
>> + ret = rpmh_invalidate(voter->dev);
>> + if (ret) {
>> + pr_err("Error invalidating RPMH client (%d)\n", ret);
>> + goto out;
>> + }
>> +
>> + 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);
>> +
>> + INIT_LIST_HEAD(&voter->commit_list);
>
> This isn't necessary, you just carefully cherry-picked everything off
> the list in the previous line.

will drop it

>
>> +
>> + 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->commit_list, 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->commit_list, 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);
>> +
>> + INIT_LIST_HEAD(&voter->commit_list);
>
> You can also remove this.

will drop it

>
>
>> + 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 bcm_voter *voter;
>> +
>> + voter = devm_kzalloc(&pdev->dev, sizeof(*voter), GFP_KERNEL);
>> + if (!voter)
>> + return -ENOMEM;
>> +
>> + voter->dev = &pdev->dev;
>> + voter->np = pdev->dev.of_node;
>> + mutex_init(&voter->lock);
>> + INIT_LIST_HEAD(&voter->commit_list);
>> + INIT_LIST_HEAD(&voter->ws_list);
>> + list_add_tail(&voter->voter_node, &bcm_voters);
>> +
>> + return 0;
>> +}
>> +
>> +static const struct of_device_id bcm_voter_of_match[] = {
>> + { .compatible = "qcom,sdm845-bcm-voter" },
>> + { },
>> +};
>> +
>> +static struct platform_driver qcom_icc_bcm_voter_driver = {
>> + .probe = qcom_icc_bcm_voter_probe,
>> + .driver = {
>> + .name = "sdm845_bcm_voter",
>> + .of_match_table = bcm_voter_of_match,
>> + },
>> +};
>> +module_platform_driver(qcom_icc_bcm_voter_driver);
>> +MODULE_AUTHOR("David Dai <daidavid1@codeaurora.org>");
>> +MODULE_DESCRIPTION("Qualcomm BCM Voter interconnect driver");
>> +MODULE_LICENSE("GPL v2");
>> +
>> diff --git a/drivers/interconnect/qcom/bcm-voter.h
>> b/drivers/interconnect/qcom/bcm-voter.h
>> new file mode 100644
>> index 0000000..808b068
>> --- /dev/null
>> +++ b/drivers/interconnect/qcom/bcm-voter.h
>> @@ -0,0 +1,28 @@
>> +/* SPDX-License-Identifier: GPL-2.0 */
>> +/*
>> + * Copyright (c) 2019, The Linux Foundation. All rights reserved.
>> + *
>> + */
>> +
>> +#ifndef __DRIVERS_INTERCONNECT_QCOM_BCM_VOTER_H__
>> +#define __DRIVERS_INTERCONNECT_QCOM_BCM_VOTER_H__
>> +
>> +#include <soc/qcom/cmd-db.h>
>> +#include <soc/qcom/rpmh.h>
>> +#include <soc/qcom/tcs.h>
>> +
>> +#include "icc-rpmh.h"
>> +
>> +#define DEFINE_QBCM(_name, _bcmname, _keepalive, _numnodes, ...)
>> \
>> + static struct qcom_icc_bcm _name = {
>> \
>> + .name = _bcmname,
>> \
>> + .keepalive = _keepalive,
>> \
>> + .num_nodes = _numnodes,
>> \

should be able to calculate the
num_nodes from VA_ARGS..

>> + .nodes = { __VA_ARGS__ },
>> \
>> + }
>> +
>> +struct bcm_voter *of_bcm_voter_get(struct device *dev, const char
>> *name);
>> +void qcom_icc_bcm_voter_add(struct bcm_voter *voter, struct
>> qcom_icc_bcm *bcm);
>> +int qcom_icc_bcm_voter_commit(struct bcm_voter *voter);
>> +
>> +#endif
>> diff --git a/drivers/interconnect/qcom/icc-rpmh.c
>> b/drivers/interconnect/qcom/icc-rpmh.c
>> new file mode 100644
>> index 0000000..09ad9fe
>> --- /dev/null
>> +++ b/drivers/interconnect/qcom/icc-rpmh.c
>> @@ -0,0 +1,158 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * Copyright (c) 2019, The Linux Foundation. All rights reserved.
>> + *
>> + */
>> +
>> +#include <asm/div64.h>

looks like ^^ should be included
in bcm_voter instead...

>> +#include <dt-bindings/interconnect/qcom,sdm845.h>

^^ not needed

>> +#include <linux/interconnect.h>
>> +#include <linux/interconnect-provider.h>
>> +#include <linux/module.h>

dropping this as well for the
reasons mentioned below.

>> +
>> +#include "bcm-voter.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;
>> +
>> + qn = node->data;
>> +
>> + for (i = 0; i < QCOM_ICC_NUM_BUCKETS; i++) {
>> + qn->sum_avg[i] = 0;
>> + qn->max_peak[i] = 0;
>> + }
>> +}
>> +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;
>> + struct qcom_icc_provider *qp;
>> +
>> + qn = node->data;
>> + qp = to_qcom_provider(node->provider);
>> +
>> + 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);
>> + }
>> + }
>> +
>> + *agg_avg += avg_bw;
>> + *agg_peak = max_t(u32, *agg_peak, peak_bw);
>> +
>> + for (i = 0; i < qn->num_bcms; i++)
>> + qcom_icc_bcm_voter_add(qp->voter, qn->bcms[i]);
>> +
>> + 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;
>> + int ret = 0;
>> +
>> + if (!src)
>> + node = dst;
>> + else
>> + node = src;
>> +
>> + qp = to_qcom_provider(node->provider);
>> +
>> + qcom_icc_bcm_voter_commit(qp->voter);
>> +
>> + return ret;
>> +}
>> +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;

I'll add a check to see if
bcm is already initialsed.

>> +
>> + 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);
>> +
>> + /*
>> + * 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);
>> +
>> +static struct platform_driver qcom_icc_rpmh_driver = {
>> + .driver = {
>> + .name = "icc_rpmh",
>> + },
>> +};
>> +module_platform_driver(qcom_icc_rpmh_driver);

I don't see any reason for ^^ to
be a module platform driver, will
remove it and list them as a set
of helper functions.

>> +MODULE_LICENSE("GPL v2");
>> diff --git a/drivers/interconnect/qcom/icc-rpmh.h
>> b/drivers/interconnect/qcom/icc-rpmh.h
>> new file mode 100644
>> index 0000000..0ff8f8d
>> --- /dev/null
>> +++ b/drivers/interconnect/qcom/icc-rpmh.h
>> @@ -0,0 +1,151 @@
>> +/* SPDX-License-Identifier: GPL-2.0 */
>> +/*
>> + * Copyright (c) 2019, The Linux Foundation. All rights reserved.
>> + *
>> + */
>> +
>> +#ifndef __DRIVERS_INTERCONNECT_QCOM_ICC_RPMH_H__
>> +#define __DRIVERS_INTERCONNECT_QCOM_ICC_RPMH_H__
>> +
>> +#define to_qcom_provider(_provider) \
>> + container_of(_provider, struct qcom_icc_provider, provider)
>> +
>> +/**
>> + * struct qcom_icc_provider - Qualcomm specific interconnect provider
>> + * @provider: generic interconnect provider
>> + * @dev: reference to the NoC device
>> + * @bcms: list of bcms that maps to the provider
>> + * @num_bcms: number of @bcms
>> + * @voter: bcm voter targeted by this provider
>> + */
>> +struct qcom_icc_provider {
>> + struct icc_provider provider;
>> + struct device *dev;
>> + struct qcom_icc_bcm **bcms;
>> + size_t num_bcms;
>> + struct bcm_voter *voter;
>> +};
>> +
>> +/**
>> + * struct bcm_db - Auxiliary data pertaining to each Bus Clock
>> Manager (BCM)
>> + * @unit: divisor used to convert bytes/sec bw value to an RPMh msg
>> + * @width: multiplier used to convert bytes/sec bw value to an RPMh
>> msg
>> + * @vcd: virtual clock domain that this bcm belongs to
>> + * @reserved: reserved field
>> + */
>> +struct bcm_db {
>> + __le32 unit;
>> + __le16 width;
>> + u8 vcd;
>> + u8 reserved;
>> +};
>> +
>> +#define MAX_LINKS 128
>> +#define MAX_BCMS 64
>> +#define MAX_BCM_PER_NODE 3
>> +#define MAX_VCD 10
>> +
>> +/*
>> + * The AMC bucket denotes constraints that are applied to hardware
>> when
>> + * icc_set_bw() completes, whereas the WAKE and SLEEP constraints are
>> applied
>> + * when the execution environment transitions between active and low
>> power mode.
>> + */
>> +#define QCOM_ICC_BUCKET_AMC 0
>> +#define QCOM_ICC_BUCKET_WAKE 1
>> +#define QCOM_ICC_BUCKET_SLEEP 2
>> +#define QCOM_ICC_NUM_BUCKETS 3
>> +#define QCOM_ICC_TAG_AMC BIT(QCOM_ICC_BUCKET_AMC)
>> +#define QCOM_ICC_TAG_WAKE BIT(QCOM_ICC_BUCKET_WAKE)
>> +#define QCOM_ICC_TAG_SLEEP BIT(QCOM_ICC_BUCKET_SLEEP)
>> +#define QCOM_ICC_TAG_ACTIVE_ONLY (QCOM_ICC_TAG_AMC |
>> QCOM_ICC_TAG_WAKE)
>> +#define QCOM_ICC_TAG_ALWAYS (QCOM_ICC_TAG_AMC |
>> QCOM_ICC_TAG_WAKE |\
>> + QCOM_ICC_TAG_SLEEP)
>> +
>> +/**
>> + * struct qcom_icc_node - Qualcomm specific interconnect nodes
>> + * @name: the node name used in debugfs
>> + * @links: an array of nodes where we can go next while traversing
>> + * @id: a unique node identifier
>> + * @num_links: the total number of @links
>> + * @channels: num of channels at this node
>> + * @buswidth: width of the interconnect between a node and the bus
>> + * @sum_avg: current sum aggregate value of all avg bw requests
>> + * @max_peak: current max aggregate value of all peak bw requests
>> + * @bcms: list of bcms associated with this logical node
>> + * @num_bcms: num of @bcms
>> + */
>> +struct qcom_icc_node {
>> + const char *name;
>> + u16 links[MAX_LINKS];
>> + u16 id;
>> + u16 num_links;
>> + u16 channels;
>> + u16 buswidth;
>> + u64 sum_avg[QCOM_ICC_NUM_BUCKETS];
>> + u64 max_peak[QCOM_ICC_NUM_BUCKETS];
>> + struct qcom_icc_bcm *bcms[MAX_BCM_PER_NODE];
>> + size_t num_bcms;
>> +};
>> +
>> +/**
>> + * struct qcom_icc_bcm - Qualcomm specific hardware accelerator nodes
>> + * known as Bus Clock Manager (BCM)
>> + * @name: the bcm node name used to fetch BCM data from command db
>> + * @type: latency or bandwidth bcm
>> + * @addr: address offsets used when voting to RPMH
>> + * @vote_x: aggregated threshold values, represents sum_bw when @type
>> is bw bcm
>> + * @vote_y: aggregated threshold values, represents peak_bw when
>> @type is bw bcm
>> + * @dirty: flag used to indicate whether the bcm needs to be
>> committed
>> + * @keepalive: flag used to indicate whether a keepalive is required
>> + * @aux_data: auxiliary data used when calculating threshold values
>> and
>> + * communicating with RPMh
>> + * @list: used to link to other bcms when compiling lists for commit
>> + * @ws_list: used to keep track of bcms that may transition between
>> wake/sleep
>> + * @num_nodes: total number of @num_nodes
>> + * @nodes: list of qcom_icc_nodes that this BCM encapsulates
>> + */
>> +struct qcom_icc_bcm {
>> + const char *name;
>> + u32 type;
>> + u32 addr;
>> + u64 vote_x[QCOM_ICC_NUM_BUCKETS];
>> + u64 vote_y[QCOM_ICC_NUM_BUCKETS];
>> + bool dirty;
>> + bool keepalive;
>> + struct bcm_db aux_data;
>> + struct list_head list;
>> + struct list_head ws_list;
>> + size_t num_nodes;
>> + struct qcom_icc_node *nodes[];
>> +};
>> +
>> +struct qcom_icc_fabric {
>> + struct qcom_icc_node **nodes;
>> + size_t num_nodes;
>> +};
>> +
>> +struct qcom_icc_desc {
>> + struct qcom_icc_node **nodes;
>> + size_t num_nodes;
>> + struct qcom_icc_bcm **bcms;
>> + size_t num_bcms;
>> +};
>> +
>> +#define DEFINE_QNODE(_name, _id, _channels, _buswidth,
>> \
>> + _numlinks, ...)
>> \
>> + static struct qcom_icc_node _name = {
>> \
>> + .id = _id,
>> \
>> + .name = #_name,
>> \
>> + .channels = _channels,
>> \
>> + .buswidth = _buswidth,
>> \
>> + .num_links = _numlinks,
>> \

should be able to calculate the
num of links from VA_ARGS...

>> + .links = { __VA_ARGS__ },
>> \
>> + }
>> +
>> +int qcom_icc_aggregate(struct icc_node *node, u32 tag, u32 avg_bw,
>> + u32 peak_bw, u32 *agg_avg, u32 *agg_peak);
>> +int qcom_icc_set(struct icc_node *src, struct icc_node *dst);
>> +int qcom_icc_bcm_init(struct qcom_icc_bcm *bcm, struct device *dev);
>> +void qcom_icc_pre_aggregate(struct icc_node *node);
>> +
>> +#endif
>> --
>> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora
>> Forum,
>> a Linux Foundation Collaborative Project

--
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project.