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linuxdebug/drivers/soc/qcom/rpmh-rsc.c

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// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2016-2018, The Linux Foundation. All rights reserved.
*/
#define pr_fmt(fmt) "%s " fmt, KBUILD_MODNAME
#include <linux/atomic.h>
#include <linux/cpu_pm.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/iopoll.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/wait.h>
#include <soc/qcom/cmd-db.h>
#include <soc/qcom/tcs.h>
#include <dt-bindings/soc/qcom,rpmh-rsc.h>
#include "rpmh-internal.h"
#define CREATE_TRACE_POINTS
#include "trace-rpmh.h"
#define RSC_DRV_TCS_OFFSET 672
#define RSC_DRV_CMD_OFFSET 20
/* DRV HW Solver Configuration Information Register */
#define DRV_SOLVER_CONFIG 0x04
#define DRV_HW_SOLVER_MASK 1
#define DRV_HW_SOLVER_SHIFT 24
/* DRV TCS Configuration Information Register */
#define DRV_PRNT_CHLD_CONFIG 0x0C
#define DRV_NUM_TCS_MASK 0x3F
#define DRV_NUM_TCS_SHIFT 6
#define DRV_NCPT_MASK 0x1F
#define DRV_NCPT_SHIFT 27
/* Offsets for common TCS Registers, one bit per TCS */
#define RSC_DRV_IRQ_ENABLE 0x00
#define RSC_DRV_IRQ_STATUS 0x04
#define RSC_DRV_IRQ_CLEAR 0x08 /* w/o; write 1 to clear */
/*
* Offsets for per TCS Registers.
*
* TCSes start at 0x10 from tcs_base and are stored one after another.
* Multiply tcs_id by RSC_DRV_TCS_OFFSET to find a given TCS and add one
* of the below to find a register.
*/
#define RSC_DRV_CMD_WAIT_FOR_CMPL 0x10 /* 1 bit per command */
#define RSC_DRV_CONTROL 0x14
#define RSC_DRV_STATUS 0x18 /* zero if tcs is busy */
#define RSC_DRV_CMD_ENABLE 0x1C /* 1 bit per command */
/*
* Offsets for per command in a TCS.
*
* Commands (up to 16) start at 0x30 in a TCS; multiply command index
* by RSC_DRV_CMD_OFFSET and add one of the below to find a register.
*/
#define RSC_DRV_CMD_MSGID 0x30
#define RSC_DRV_CMD_ADDR 0x34
#define RSC_DRV_CMD_DATA 0x38
#define RSC_DRV_CMD_STATUS 0x3C
#define RSC_DRV_CMD_RESP_DATA 0x40
#define TCS_AMC_MODE_ENABLE BIT(16)
#define TCS_AMC_MODE_TRIGGER BIT(24)
/* TCS CMD register bit mask */
#define CMD_MSGID_LEN 8
#define CMD_MSGID_RESP_REQ BIT(8)
#define CMD_MSGID_WRITE BIT(16)
#define CMD_STATUS_ISSUED BIT(8)
#define CMD_STATUS_COMPL BIT(16)
/*
* Here's a high level overview of how all the registers in RPMH work
* together:
*
* - The main rpmh-rsc address is the base of a register space that can
* be used to find overall configuration of the hardware
* (DRV_PRNT_CHLD_CONFIG). Also found within the rpmh-rsc register
* space are all the TCS blocks. The offset of the TCS blocks is
* specified in the device tree by "qcom,tcs-offset" and used to
* compute tcs_base.
* - TCS blocks come one after another. Type, count, and order are
* specified by the device tree as "qcom,tcs-config".
* - Each TCS block has some registers, then space for up to 16 commands.
* Note that though address space is reserved for 16 commands, fewer
* might be present. See ncpt (num cmds per TCS).
*
* Here's a picture:
*
* +---------------------------------------------------+
* |RSC |
* | ctrl |
* | |
* | Drvs: |
* | +-----------------------------------------------+ |
* | |DRV0 | |
* | | ctrl/config | |
* | | IRQ | |
* | | | |
* | | TCSes: | |
* | | +------------------------------------------+ | |
* | | |TCS0 | | | | | | | | | | | | | | |
* | | | ctrl | 0| 1| 2| 3| 4| 5| .| .| .| .|14|15| | |
* | | | | | | | | | | | | | | | | | |
* | | +------------------------------------------+ | |
* | | +------------------------------------------+ | |
* | | |TCS1 | | | | | | | | | | | | | | |
* | | | ctrl | 0| 1| 2| 3| 4| 5| .| .| .| .|14|15| | |
* | | | | | | | | | | | | | | | | | |
* | | +------------------------------------------+ | |
* | | +------------------------------------------+ | |
* | | |TCS2 | | | | | | | | | | | | | | |
* | | | ctrl | 0| 1| 2| 3| 4| 5| .| .| .| .|14|15| | |
* | | | | | | | | | | | | | | | | | |
* | | +------------------------------------------+ | |
* | | ...... | |
* | +-----------------------------------------------+ |
* | +-----------------------------------------------+ |
* | |DRV1 | |
* | | (same as DRV0) | |
* | +-----------------------------------------------+ |
* | ...... |
* +---------------------------------------------------+
*/
static inline void __iomem *
tcs_reg_addr(const struct rsc_drv *drv, int reg, int tcs_id)
{
return drv->tcs_base + RSC_DRV_TCS_OFFSET * tcs_id + reg;
}
static inline void __iomem *
tcs_cmd_addr(const struct rsc_drv *drv, int reg, int tcs_id, int cmd_id)
{
return tcs_reg_addr(drv, reg, tcs_id) + RSC_DRV_CMD_OFFSET * cmd_id;
}
static u32 read_tcs_cmd(const struct rsc_drv *drv, int reg, int tcs_id,
int cmd_id)
{
return readl_relaxed(tcs_cmd_addr(drv, reg, tcs_id, cmd_id));
}
static u32 read_tcs_reg(const struct rsc_drv *drv, int reg, int tcs_id)
{
return readl_relaxed(tcs_reg_addr(drv, reg, tcs_id));
}
static void write_tcs_cmd(const struct rsc_drv *drv, int reg, int tcs_id,
int cmd_id, u32 data)
{
writel_relaxed(data, tcs_cmd_addr(drv, reg, tcs_id, cmd_id));
}
static void write_tcs_reg(const struct rsc_drv *drv, int reg, int tcs_id,
u32 data)
{
writel_relaxed(data, tcs_reg_addr(drv, reg, tcs_id));
}
static void write_tcs_reg_sync(const struct rsc_drv *drv, int reg, int tcs_id,
u32 data)
{
int i;
writel(data, tcs_reg_addr(drv, reg, tcs_id));
/*
* Wait until we read back the same value. Use a counter rather than
* ktime for timeout since this may be called after timekeeping stops.
*/
for (i = 0; i < USEC_PER_SEC; i++) {
if (readl(tcs_reg_addr(drv, reg, tcs_id)) == data)
return;
udelay(1);
}
pr_err("%s: error writing %#x to %d:%#x\n", drv->name,
data, tcs_id, reg);
}
/**
* tcs_invalidate() - Invalidate all TCSes of the given type (sleep or wake).
* @drv: The RSC controller.
* @type: SLEEP_TCS or WAKE_TCS
*
* This will clear the "slots" variable of the given tcs_group and also
* tell the hardware to forget about all entries.
*
* The caller must ensure that no other RPMH actions are happening when this
* function is called, since otherwise the device may immediately become
* used again even before this function exits.
*/
static void tcs_invalidate(struct rsc_drv *drv, int type)
{
int m;
struct tcs_group *tcs = &drv->tcs[type];
/* Caller ensures nobody else is running so no lock */
if (bitmap_empty(tcs->slots, MAX_TCS_SLOTS))
return;
for (m = tcs->offset; m < tcs->offset + tcs->num_tcs; m++)
write_tcs_reg_sync(drv, RSC_DRV_CMD_ENABLE, m, 0);
bitmap_zero(tcs->slots, MAX_TCS_SLOTS);
}
/**
* rpmh_rsc_invalidate() - Invalidate sleep and wake TCSes.
* @drv: The RSC controller.
*
* The caller must ensure that no other RPMH actions are happening when this
* function is called, since otherwise the device may immediately become
* used again even before this function exits.
*/
void rpmh_rsc_invalidate(struct rsc_drv *drv)
{
tcs_invalidate(drv, SLEEP_TCS);
tcs_invalidate(drv, WAKE_TCS);
}
/**
* get_tcs_for_msg() - Get the tcs_group used to send the given message.
* @drv: The RSC controller.
* @msg: The message we want to send.
*
* This is normally pretty straightforward except if we are trying to send
* an ACTIVE_ONLY message but don't have any active_only TCSes.
*
* Return: A pointer to a tcs_group or an ERR_PTR.
*/
static struct tcs_group *get_tcs_for_msg(struct rsc_drv *drv,
const struct tcs_request *msg)
{
int type;
struct tcs_group *tcs;
switch (msg->state) {
case RPMH_ACTIVE_ONLY_STATE:
type = ACTIVE_TCS;
break;
case RPMH_WAKE_ONLY_STATE:
type = WAKE_TCS;
break;
case RPMH_SLEEP_STATE:
type = SLEEP_TCS;
break;
default:
return ERR_PTR(-EINVAL);
}
/*
* If we are making an active request on a RSC that does not have a
* dedicated TCS for active state use, then re-purpose a wake TCS to
* send active votes. This is safe because we ensure any active-only
* transfers have finished before we use it (maybe by running from
* the last CPU in PM code).
*/
tcs = &drv->tcs[type];
if (msg->state == RPMH_ACTIVE_ONLY_STATE && !tcs->num_tcs)
tcs = &drv->tcs[WAKE_TCS];
return tcs;
}
/**
* get_req_from_tcs() - Get a stashed request that was xfering on the given TCS.
* @drv: The RSC controller.
* @tcs_id: The global ID of this TCS.
*
* For ACTIVE_ONLY transfers we want to call back into the client when the
* transfer finishes. To do this we need the "request" that the client
* originally provided us. This function grabs the request that we stashed
* when we started the transfer.
*
* This only makes sense for ACTIVE_ONLY transfers since those are the only
* ones we track sending (the only ones we enable interrupts for and the only
* ones we call back to the client for).
*
* Return: The stashed request.
*/
static const struct tcs_request *get_req_from_tcs(struct rsc_drv *drv,
int tcs_id)
{
struct tcs_group *tcs;
int i;
for (i = 0; i < TCS_TYPE_NR; i++) {
tcs = &drv->tcs[i];
if (tcs->mask & BIT(tcs_id))
return tcs->req[tcs_id - tcs->offset];
}
return NULL;
}
/**
* __tcs_set_trigger() - Start xfer on a TCS or unset trigger on a borrowed TCS
* @drv: The controller.
* @tcs_id: The global ID of this TCS.
* @trigger: If true then untrigger/retrigger. If false then just untrigger.
*
* In the normal case we only ever call with "trigger=true" to start a
* transfer. That will un-trigger/disable the TCS from the last transfer
* then trigger/enable for this transfer.
*
* If we borrowed a wake TCS for an active-only transfer we'll also call
* this function with "trigger=false" to just do the un-trigger/disable
* before using the TCS for wake purposes again.
*
* Note that the AP is only in charge of triggering active-only transfers.
* The AP never triggers sleep/wake values using this function.
*/
static void __tcs_set_trigger(struct rsc_drv *drv, int tcs_id, bool trigger)
{
u32 enable;
/*
* HW req: Clear the DRV_CONTROL and enable TCS again
* While clearing ensure that the AMC mode trigger is cleared
* and then the mode enable is cleared.
*/
enable = read_tcs_reg(drv, RSC_DRV_CONTROL, tcs_id);
enable &= ~TCS_AMC_MODE_TRIGGER;
write_tcs_reg_sync(drv, RSC_DRV_CONTROL, tcs_id, enable);
enable &= ~TCS_AMC_MODE_ENABLE;
write_tcs_reg_sync(drv, RSC_DRV_CONTROL, tcs_id, enable);
if (trigger) {
/* Enable the AMC mode on the TCS and then trigger the TCS */
enable = TCS_AMC_MODE_ENABLE;
write_tcs_reg_sync(drv, RSC_DRV_CONTROL, tcs_id, enable);
enable |= TCS_AMC_MODE_TRIGGER;
write_tcs_reg(drv, RSC_DRV_CONTROL, tcs_id, enable);
}
}
/**
* enable_tcs_irq() - Enable or disable interrupts on the given TCS.
* @drv: The controller.
* @tcs_id: The global ID of this TCS.
* @enable: If true then enable; if false then disable
*
* We only ever call this when we borrow a wake TCS for an active-only
* transfer. For active-only TCSes interrupts are always left enabled.
*/
static void enable_tcs_irq(struct rsc_drv *drv, int tcs_id, bool enable)
{
u32 data;
data = readl_relaxed(drv->tcs_base + RSC_DRV_IRQ_ENABLE);
if (enable)
data |= BIT(tcs_id);
else
data &= ~BIT(tcs_id);
writel_relaxed(data, drv->tcs_base + RSC_DRV_IRQ_ENABLE);
}
/**
* tcs_tx_done() - TX Done interrupt handler.
* @irq: The IRQ number (ignored).
* @p: Pointer to "struct rsc_drv".
*
* Called for ACTIVE_ONLY transfers (those are the only ones we enable the
* IRQ for) when a transfer is done.
*
* Return: IRQ_HANDLED
*/
static irqreturn_t tcs_tx_done(int irq, void *p)
{
struct rsc_drv *drv = p;
int i, j, err = 0;
unsigned long irq_status;
const struct tcs_request *req;
struct tcs_cmd *cmd;
irq_status = readl_relaxed(drv->tcs_base + RSC_DRV_IRQ_STATUS);
for_each_set_bit(i, &irq_status, BITS_PER_TYPE(u32)) {
req = get_req_from_tcs(drv, i);
if (WARN_ON(!req))
goto skip;
err = 0;
for (j = 0; j < req->num_cmds; j++) {
u32 sts;
cmd = &req->cmds[j];
sts = read_tcs_cmd(drv, RSC_DRV_CMD_STATUS, i, j);
if (!(sts & CMD_STATUS_ISSUED) ||
((req->wait_for_compl || cmd->wait) &&
!(sts & CMD_STATUS_COMPL))) {
pr_err("Incomplete request: %s: addr=%#x data=%#x",
drv->name, cmd->addr, cmd->data);
err = -EIO;
}
}
trace_rpmh_tx_done(drv, i, req, err);
/*
* If wake tcs was re-purposed for sending active
* votes, clear AMC trigger & enable modes and
* disable interrupt for this TCS
*/
if (!drv->tcs[ACTIVE_TCS].num_tcs)
__tcs_set_trigger(drv, i, false);
skip:
/* Reclaim the TCS */
write_tcs_reg(drv, RSC_DRV_CMD_ENABLE, i, 0);
writel_relaxed(BIT(i), drv->tcs_base + RSC_DRV_IRQ_CLEAR);
spin_lock(&drv->lock);
clear_bit(i, drv->tcs_in_use);
/*
* Disable interrupt for WAKE TCS to avoid being
* spammed with interrupts coming when the solver
* sends its wake votes.
*/
if (!drv->tcs[ACTIVE_TCS].num_tcs)
enable_tcs_irq(drv, i, false);
spin_unlock(&drv->lock);
wake_up(&drv->tcs_wait);
if (req)
rpmh_tx_done(req, err);
}
return IRQ_HANDLED;
}
/**
* __tcs_buffer_write() - Write to TCS hardware from a request; don't trigger.
* @drv: The controller.
* @tcs_id: The global ID of this TCS.
* @cmd_id: The index within the TCS to start writing.
* @msg: The message we want to send, which will contain several addr/data
* pairs to program (but few enough that they all fit in one TCS).
*
* This is used for all types of transfers (active, sleep, and wake).
*/
static void __tcs_buffer_write(struct rsc_drv *drv, int tcs_id, int cmd_id,
const struct tcs_request *msg)
{
u32 msgid;
u32 cmd_msgid = CMD_MSGID_LEN | CMD_MSGID_WRITE;
u32 cmd_enable = 0;
struct tcs_cmd *cmd;
int i, j;
/* Convert all commands to RR when the request has wait_for_compl set */
cmd_msgid |= msg->wait_for_compl ? CMD_MSGID_RESP_REQ : 0;
for (i = 0, j = cmd_id; i < msg->num_cmds; i++, j++) {
cmd = &msg->cmds[i];
cmd_enable |= BIT(j);
msgid = cmd_msgid;
/*
* Additionally, if the cmd->wait is set, make the command
* response reqd even if the overall request was fire-n-forget.
*/
msgid |= cmd->wait ? CMD_MSGID_RESP_REQ : 0;
write_tcs_cmd(drv, RSC_DRV_CMD_MSGID, tcs_id, j, msgid);
write_tcs_cmd(drv, RSC_DRV_CMD_ADDR, tcs_id, j, cmd->addr);
write_tcs_cmd(drv, RSC_DRV_CMD_DATA, tcs_id, j, cmd->data);
trace_rpmh_send_msg(drv, tcs_id, j, msgid, cmd);
}
cmd_enable |= read_tcs_reg(drv, RSC_DRV_CMD_ENABLE, tcs_id);
write_tcs_reg(drv, RSC_DRV_CMD_ENABLE, tcs_id, cmd_enable);
}
/**
* check_for_req_inflight() - Look to see if conflicting cmds are in flight.
* @drv: The controller.
* @tcs: A pointer to the tcs_group used for ACTIVE_ONLY transfers.
* @msg: The message we want to send, which will contain several addr/data
* pairs to program (but few enough that they all fit in one TCS).
*
* This will walk through the TCSes in the group and check if any of them
* appear to be sending to addresses referenced in the message. If it finds
* one it'll return -EBUSY.
*
* Only for use for active-only transfers.
*
* Must be called with the drv->lock held since that protects tcs_in_use.
*
* Return: 0 if nothing in flight or -EBUSY if we should try again later.
* The caller must re-enable interrupts between tries since that's
* the only way tcs_in_use will ever be updated and the only way
* RSC_DRV_CMD_ENABLE will ever be cleared.
*/
static int check_for_req_inflight(struct rsc_drv *drv, struct tcs_group *tcs,
const struct tcs_request *msg)
{
unsigned long curr_enabled;
u32 addr;
int j, k;
int i = tcs->offset;
for_each_set_bit_from(i, drv->tcs_in_use, tcs->offset + tcs->num_tcs) {
curr_enabled = read_tcs_reg(drv, RSC_DRV_CMD_ENABLE, i);
for_each_set_bit(j, &curr_enabled, MAX_CMDS_PER_TCS) {
addr = read_tcs_cmd(drv, RSC_DRV_CMD_ADDR, i, j);
for (k = 0; k < msg->num_cmds; k++) {
if (addr == msg->cmds[k].addr)
return -EBUSY;
}
}
}
return 0;
}
/**
* find_free_tcs() - Find free tcs in the given tcs_group; only for active.
* @tcs: A pointer to the active-only tcs_group (or the wake tcs_group if
* we borrowed it because there are zero active-only ones).
*
* Must be called with the drv->lock held since that protects tcs_in_use.
*
* Return: The first tcs that's free or -EBUSY if all in use.
*/
static int find_free_tcs(struct tcs_group *tcs)
{
const struct rsc_drv *drv = tcs->drv;
unsigned long i;
unsigned long max = tcs->offset + tcs->num_tcs;
i = find_next_zero_bit(drv->tcs_in_use, max, tcs->offset);
if (i >= max)
return -EBUSY;
return i;
}
/**
* claim_tcs_for_req() - Claim a tcs in the given tcs_group; only for active.
* @drv: The controller.
* @tcs: The tcs_group used for ACTIVE_ONLY transfers.
* @msg: The data to be sent.
*
* Claims a tcs in the given tcs_group while making sure that no existing cmd
* is in flight that would conflict with the one in @msg.
*
* Context: Must be called with the drv->lock held since that protects
* tcs_in_use.
*
* Return: The id of the claimed tcs or -EBUSY if a matching msg is in flight
* or the tcs_group is full.
*/
static int claim_tcs_for_req(struct rsc_drv *drv, struct tcs_group *tcs,
const struct tcs_request *msg)
{
int ret;
/*
* The h/w does not like if we send a request to the same address,
* when one is already in-flight or being processed.
*/
ret = check_for_req_inflight(drv, tcs, msg);
if (ret)
return ret;
return find_free_tcs(tcs);
}
/**
* rpmh_rsc_send_data() - Write / trigger active-only message.
* @drv: The controller.
* @msg: The data to be sent.
*
* NOTES:
* - This is only used for "ACTIVE_ONLY" since the limitations of this
* function don't make sense for sleep/wake cases.
* - To do the transfer, we will grab a whole TCS for ourselves--we don't
* try to share. If there are none available we'll wait indefinitely
* for a free one.
* - This function will not wait for the commands to be finished, only for
* data to be programmed into the RPMh. See rpmh_tx_done() which will
* be called when the transfer is fully complete.
* - This function must be called with interrupts enabled. If the hardware
* is busy doing someone else's transfer we need that transfer to fully
* finish so that we can have the hardware, and to fully finish it needs
* the interrupt handler to run. If the interrupts is set to run on the
* active CPU this can never happen if interrupts are disabled.
*
* Return: 0 on success, -EINVAL on error.
*/
int rpmh_rsc_send_data(struct rsc_drv *drv, const struct tcs_request *msg)
{
struct tcs_group *tcs;
int tcs_id;
unsigned long flags;
tcs = get_tcs_for_msg(drv, msg);
if (IS_ERR(tcs))
return PTR_ERR(tcs);
spin_lock_irqsave(&drv->lock, flags);
/* Wait forever for a free tcs. It better be there eventually! */
wait_event_lock_irq(drv->tcs_wait,
(tcs_id = claim_tcs_for_req(drv, tcs, msg)) >= 0,
drv->lock);
tcs->req[tcs_id - tcs->offset] = msg;
set_bit(tcs_id, drv->tcs_in_use);
if (msg->state == RPMH_ACTIVE_ONLY_STATE && tcs->type != ACTIVE_TCS) {
/*
* Clear previously programmed WAKE commands in selected
* repurposed TCS to avoid triggering them. tcs->slots will be
* cleaned from rpmh_flush() by invoking rpmh_rsc_invalidate()
*/
write_tcs_reg_sync(drv, RSC_DRV_CMD_ENABLE, tcs_id, 0);
enable_tcs_irq(drv, tcs_id, true);
}
spin_unlock_irqrestore(&drv->lock, flags);
/*
* These two can be done after the lock is released because:
* - We marked "tcs_in_use" under lock.
* - Once "tcs_in_use" has been marked nobody else could be writing
* to these registers until the interrupt goes off.
* - The interrupt can't go off until we trigger w/ the last line
* of __tcs_set_trigger() below.
*/
__tcs_buffer_write(drv, tcs_id, 0, msg);
__tcs_set_trigger(drv, tcs_id, true);
return 0;
}
/**
* find_slots() - Find a place to write the given message.
* @tcs: The tcs group to search.
* @msg: The message we want to find room for.
* @tcs_id: If we return 0 from the function, we return the global ID of the
* TCS to write to here.
* @cmd_id: If we return 0 from the function, we return the index of
* the command array of the returned TCS where the client should
* start writing the message.
*
* Only for use on sleep/wake TCSes since those are the only ones we maintain
* tcs->slots for.
*
* Return: -ENOMEM if there was no room, else 0.
*/
static int find_slots(struct tcs_group *tcs, const struct tcs_request *msg,
int *tcs_id, int *cmd_id)
{
int slot, offset;
int i = 0;
/* Do over, until we can fit the full payload in a single TCS */
do {
slot = bitmap_find_next_zero_area(tcs->slots, MAX_TCS_SLOTS,
i, msg->num_cmds, 0);
if (slot >= tcs->num_tcs * tcs->ncpt)
return -ENOMEM;
i += tcs->ncpt;
} while (slot + msg->num_cmds - 1 >= i);
bitmap_set(tcs->slots, slot, msg->num_cmds);
offset = slot / tcs->ncpt;
*tcs_id = offset + tcs->offset;
*cmd_id = slot % tcs->ncpt;
return 0;
}
/**
* rpmh_rsc_write_ctrl_data() - Write request to controller but don't trigger.
* @drv: The controller.
* @msg: The data to be written to the controller.
*
* This should only be called for sleep/wake state, never active-only
* state.
*
* The caller must ensure that no other RPMH actions are happening and the
* controller is idle when this function is called since it runs lockless.
*
* Return: 0 if no error; else -error.
*/
int rpmh_rsc_write_ctrl_data(struct rsc_drv *drv, const struct tcs_request *msg)
{
struct tcs_group *tcs;
int tcs_id = 0, cmd_id = 0;
int ret;
tcs = get_tcs_for_msg(drv, msg);
if (IS_ERR(tcs))
return PTR_ERR(tcs);
/* find the TCS id and the command in the TCS to write to */
ret = find_slots(tcs, msg, &tcs_id, &cmd_id);
if (!ret)
__tcs_buffer_write(drv, tcs_id, cmd_id, msg);
return ret;
}
/**
* rpmh_rsc_ctrlr_is_busy() - Check if any of the AMCs are busy.
* @drv: The controller
*
* Checks if any of the AMCs are busy in handling ACTIVE sets.
* This is called from the last cpu powering down before flushing
* SLEEP and WAKE sets. If AMCs are busy, controller can not enter
* power collapse, so deny from the last cpu's pm notification.
*
* Context: Must be called with the drv->lock held.
*
* Return:
* * False - AMCs are idle
* * True - AMCs are busy
*/
static bool rpmh_rsc_ctrlr_is_busy(struct rsc_drv *drv)
{
unsigned long set;
const struct tcs_group *tcs = &drv->tcs[ACTIVE_TCS];
unsigned long max;
/*
* If we made an active request on a RSC that does not have a
* dedicated TCS for active state use, then re-purposed wake TCSes
* should be checked for not busy, because we used wake TCSes for
* active requests in this case.
*/
if (!tcs->num_tcs)
tcs = &drv->tcs[WAKE_TCS];
max = tcs->offset + tcs->num_tcs;
set = find_next_bit(drv->tcs_in_use, max, tcs->offset);
return set < max;
}
/**
* rpmh_rsc_cpu_pm_callback() - Check if any of the AMCs are busy.
* @nfb: Pointer to the notifier block in struct rsc_drv.
* @action: CPU_PM_ENTER, CPU_PM_ENTER_FAILED, or CPU_PM_EXIT.
* @v: Unused
*
* This function is given to cpu_pm_register_notifier so we can be informed
* about when CPUs go down. When all CPUs go down we know no more active
* transfers will be started so we write sleep/wake sets. This function gets
* called from cpuidle code paths and also at system suspend time.
*
* If its last CPU going down and AMCs are not busy then writes cached sleep
* and wake messages to TCSes. The firmware then takes care of triggering
* them when entering deepest low power modes.
*
* Return: See cpu_pm_register_notifier()
*/
static int rpmh_rsc_cpu_pm_callback(struct notifier_block *nfb,
unsigned long action, void *v)
{
struct rsc_drv *drv = container_of(nfb, struct rsc_drv, rsc_pm);
int ret = NOTIFY_OK;
int cpus_in_pm;
switch (action) {
case CPU_PM_ENTER:
cpus_in_pm = atomic_inc_return(&drv->cpus_in_pm);
/*
* NOTE: comments for num_online_cpus() point out that it's
* only a snapshot so we need to be careful. It should be OK
* for us to use, though. It's important for us not to miss
* if we're the last CPU going down so it would only be a
* problem if a CPU went offline right after we did the check
* AND that CPU was not idle AND that CPU was the last non-idle
* CPU. That can't happen. CPUs would have to come out of idle
* before the CPU could go offline.
*/
if (cpus_in_pm < num_online_cpus())
return NOTIFY_OK;
break;
case CPU_PM_ENTER_FAILED:
case CPU_PM_EXIT:
atomic_dec(&drv->cpus_in_pm);
return NOTIFY_OK;
default:
return NOTIFY_DONE;
}
/*
* It's likely we're on the last CPU. Grab the drv->lock and write
* out the sleep/wake commands to RPMH hardware. Grabbing the lock
* means that if we race with another CPU coming up we are still
* guaranteed to be safe. If another CPU came up just after we checked
* and has grabbed the lock or started an active transfer then we'll
* notice we're busy and abort. If another CPU comes up after we start
* flushing it will be blocked from starting an active transfer until
* we're done flushing. If another CPU starts an active transfer after
* we release the lock we're still OK because we're no longer the last
* CPU.
*/
if (spin_trylock(&drv->lock)) {
if (rpmh_rsc_ctrlr_is_busy(drv) || rpmh_flush(&drv->client))
ret = NOTIFY_BAD;
spin_unlock(&drv->lock);
} else {
/* Another CPU must be up */
return NOTIFY_OK;
}
if (ret == NOTIFY_BAD) {
/* Double-check if we're here because someone else is up */
if (cpus_in_pm < num_online_cpus())
ret = NOTIFY_OK;
else
/* We won't be called w/ CPU_PM_ENTER_FAILED */
atomic_dec(&drv->cpus_in_pm);
}
return ret;
}
static int rpmh_probe_tcs_config(struct platform_device *pdev,
struct rsc_drv *drv, void __iomem *base)
{
struct tcs_type_config {
u32 type;
u32 n;
} tcs_cfg[TCS_TYPE_NR] = { { 0 } };
struct device_node *dn = pdev->dev.of_node;
u32 config, max_tcs, ncpt, offset;
int i, ret, n, st = 0;
struct tcs_group *tcs;
ret = of_property_read_u32(dn, "qcom,tcs-offset", &offset);
if (ret)
return ret;
drv->tcs_base = base + offset;
config = readl_relaxed(base + DRV_PRNT_CHLD_CONFIG);
max_tcs = config;
max_tcs &= DRV_NUM_TCS_MASK << (DRV_NUM_TCS_SHIFT * drv->id);
max_tcs = max_tcs >> (DRV_NUM_TCS_SHIFT * drv->id);
ncpt = config & (DRV_NCPT_MASK << DRV_NCPT_SHIFT);
ncpt = ncpt >> DRV_NCPT_SHIFT;
n = of_property_count_u32_elems(dn, "qcom,tcs-config");
if (n != 2 * TCS_TYPE_NR)
return -EINVAL;
for (i = 0; i < TCS_TYPE_NR; i++) {
ret = of_property_read_u32_index(dn, "qcom,tcs-config",
i * 2, &tcs_cfg[i].type);
if (ret)
return ret;
if (tcs_cfg[i].type >= TCS_TYPE_NR)
return -EINVAL;
ret = of_property_read_u32_index(dn, "qcom,tcs-config",
i * 2 + 1, &tcs_cfg[i].n);
if (ret)
return ret;
if (tcs_cfg[i].n > MAX_TCS_PER_TYPE)
return -EINVAL;
}
for (i = 0; i < TCS_TYPE_NR; i++) {
tcs = &drv->tcs[tcs_cfg[i].type];
if (tcs->drv)
return -EINVAL;
tcs->drv = drv;
tcs->type = tcs_cfg[i].type;
tcs->num_tcs = tcs_cfg[i].n;
tcs->ncpt = ncpt;
if (!tcs->num_tcs || tcs->type == CONTROL_TCS)
continue;
if (st + tcs->num_tcs > max_tcs ||
st + tcs->num_tcs >= BITS_PER_BYTE * sizeof(tcs->mask))
return -EINVAL;
tcs->mask = ((1 << tcs->num_tcs) - 1) << st;
tcs->offset = st;
st += tcs->num_tcs;
}
drv->num_tcs = st;
return 0;
}
static int rpmh_rsc_probe(struct platform_device *pdev)
{
struct device_node *dn = pdev->dev.of_node;
struct rsc_drv *drv;
char drv_id[10] = {0};
int ret, irq;
u32 solver_config;
void __iomem *base;
/*
* Even though RPMh doesn't directly use cmd-db, all of its children
* do. To avoid adding this check to our children we'll do it now.
*/
ret = cmd_db_ready();
if (ret) {
if (ret != -EPROBE_DEFER)
dev_err(&pdev->dev, "Command DB not available (%d)\n",
ret);
return ret;
}
drv = devm_kzalloc(&pdev->dev, sizeof(*drv), GFP_KERNEL);
if (!drv)
return -ENOMEM;
ret = of_property_read_u32(dn, "qcom,drv-id", &drv->id);
if (ret)
return ret;
drv->name = of_get_property(dn, "label", NULL);
if (!drv->name)
drv->name = dev_name(&pdev->dev);
snprintf(drv_id, ARRAY_SIZE(drv_id), "drv-%d", drv->id);
base = devm_platform_ioremap_resource_byname(pdev, drv_id);
if (IS_ERR(base))
return PTR_ERR(base);
ret = rpmh_probe_tcs_config(pdev, drv, base);
if (ret)
return ret;
spin_lock_init(&drv->lock);
init_waitqueue_head(&drv->tcs_wait);
bitmap_zero(drv->tcs_in_use, MAX_TCS_NR);
irq = platform_get_irq(pdev, drv->id);
if (irq < 0)
return irq;
ret = devm_request_irq(&pdev->dev, irq, tcs_tx_done,
IRQF_TRIGGER_HIGH | IRQF_NO_SUSPEND,
drv->name, drv);
if (ret)
return ret;
/*
* CPU PM notification are not required for controllers that support
* 'HW solver' mode where they can be in autonomous mode executing low
* power mode to power down.
*/
solver_config = readl_relaxed(base + DRV_SOLVER_CONFIG);
solver_config &= DRV_HW_SOLVER_MASK << DRV_HW_SOLVER_SHIFT;
solver_config = solver_config >> DRV_HW_SOLVER_SHIFT;
if (!solver_config) {
drv->rsc_pm.notifier_call = rpmh_rsc_cpu_pm_callback;
cpu_pm_register_notifier(&drv->rsc_pm);
}
/* Enable the active TCS to send requests immediately */
writel_relaxed(drv->tcs[ACTIVE_TCS].mask,
drv->tcs_base + RSC_DRV_IRQ_ENABLE);
spin_lock_init(&drv->client.cache_lock);
INIT_LIST_HEAD(&drv->client.cache);
INIT_LIST_HEAD(&drv->client.batch_cache);
dev_set_drvdata(&pdev->dev, drv);
return devm_of_platform_populate(&pdev->dev);
}
static const struct of_device_id rpmh_drv_match[] = {
{ .compatible = "qcom,rpmh-rsc", },
{ }
};
MODULE_DEVICE_TABLE(of, rpmh_drv_match);
static struct platform_driver rpmh_driver = {
.probe = rpmh_rsc_probe,
.driver = {
.name = "rpmh",
.of_match_table = rpmh_drv_match,
.suppress_bind_attrs = true,
},
};
static int __init rpmh_driver_init(void)
{
return platform_driver_register(&rpmh_driver);
}
arch_initcall(rpmh_driver_init);
MODULE_DESCRIPTION("Qualcomm Technologies, Inc. RPMh Driver");
MODULE_LICENSE("GPL v2");
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