// 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #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 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; struct resource *res; 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); res = platform_get_resource_byname(pdev, IORESOURCE_MEM, drv_id); base = devm_ioremap_resource(&pdev->dev, res); 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");