diff mbox series

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

Message ID 1578630784-962-5-git-send-email-daidavid1@codeaurora.org
State New
Headers show
Series [v2,1/6] dt-bindings: interconnect: Convert qcom,sdm845 to DT schema | expand

Commit Message

David Dai Jan. 10, 2020, 4:33 a.m. UTC
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>
---
 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

Comments

Sibi Sankar Feb. 9, 2020, 5:58 p.m. UTC | #1
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
diff mbox series

Patch

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
+
 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
+
 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
 
+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);
+
+/**
+ * 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],
+			 int n[MAX_VCD])
+{
+	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;
+				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);
+
+	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);
+	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,					\
+		.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>
+#include <dt-bindings/interconnect/qcom,sdm845.h>
+#include <linux/interconnect.h>
+#include <linux/interconnect-provider.h>
+#include <linux/module.h>
+
+#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;
+
+	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);
+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,					\
+		.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