// SPDX-License-Identifier: GPL-2.0 /* * Copyright (c) 2011-2017, The Linux Foundation */ #include <linux/slab.h> #include <linux/pm_runtime.h> #include "slimbus.h" /** * slim_msg_response() - Deliver Message response received from a device to the * framework. * * @ctrl: Controller handle * @reply: Reply received from the device * @len: Length of the reply * @tid: Transaction ID received with which framework can associate reply. * * Called by controller to inform framework about the response received. * This helps in making the API asynchronous, and controller-driver doesn't need * to manage 1 more table other than the one managed by framework mapping TID * with buffers */ void slim_msg_response(struct slim_controller *ctrl, u8 *reply, u8 tid, u8 len) { struct slim_msg_txn *txn; struct slim_val_inf *msg; unsigned long flags; spin_lock_irqsave(&ctrl->txn_lock, flags); txn = idr_find(&ctrl->tid_idr, tid); spin_unlock_irqrestore(&ctrl->txn_lock, flags); if (txn == NULL) return; msg = txn->msg; if (msg == NULL || msg->rbuf == NULL) { dev_err(ctrl->dev, "Got response to invalid TID:%d, len:%d\n", tid, len); return; } slim_free_txn_tid(ctrl, txn); memcpy(msg->rbuf, reply, len); if (txn->comp) complete(txn->comp); /* Remove runtime-pm vote now that response was received for TID txn */ pm_runtime_mark_last_busy(ctrl->dev); pm_runtime_put_autosuspend(ctrl->dev); } EXPORT_SYMBOL_GPL(slim_msg_response); /** * slim_alloc_txn_tid() - Allocate a tid to txn * * @ctrl: Controller handle * @txn: transaction to be allocated with tid. * * Return: zero on success with valid txn->tid and error code on failures. */ int slim_alloc_txn_tid(struct slim_controller *ctrl, struct slim_msg_txn *txn) { unsigned long flags; int ret = 0; spin_lock_irqsave(&ctrl->txn_lock, flags); ret = idr_alloc_cyclic(&ctrl->tid_idr, txn, 1, SLIM_MAX_TIDS, GFP_ATOMIC); if (ret < 0) { spin_unlock_irqrestore(&ctrl->txn_lock, flags); return ret; } txn->tid = ret; spin_unlock_irqrestore(&ctrl->txn_lock, flags); return 0; } EXPORT_SYMBOL_GPL(slim_alloc_txn_tid); /** * slim_free_txn_tid() - Freee tid of txn * * @ctrl: Controller handle * @txn: transaction whose tid should be freed */ void slim_free_txn_tid(struct slim_controller *ctrl, struct slim_msg_txn *txn) { unsigned long flags; spin_lock_irqsave(&ctrl->txn_lock, flags); idr_remove(&ctrl->tid_idr, txn->tid); spin_unlock_irqrestore(&ctrl->txn_lock, flags); } EXPORT_SYMBOL_GPL(slim_free_txn_tid); /** * slim_do_transfer() - Process a SLIMbus-messaging transaction * * @ctrl: Controller handle * @txn: Transaction to be sent over SLIMbus * * Called by controller to transmit messaging transactions not dealing with * Interface/Value elements. (e.g. transmittting a message to assign logical * address to a slave device * * Return: -ETIMEDOUT: If transmission of this message timed out * (e.g. due to bus lines not being clocked or driven by controller) */ int slim_do_transfer(struct slim_controller *ctrl, struct slim_msg_txn *txn) { DECLARE_COMPLETION_ONSTACK(done); bool need_tid = false, clk_pause_msg = false; int ret, timeout; /* * do not vote for runtime-PM if the transactions are part of clock * pause sequence */ if (ctrl->sched.clk_state == SLIM_CLK_ENTERING_PAUSE && (txn->mt == SLIM_MSG_MT_CORE && txn->mc >= SLIM_MSG_MC_BEGIN_RECONFIGURATION && txn->mc <= SLIM_MSG_MC_RECONFIGURE_NOW)) clk_pause_msg = true; if (!clk_pause_msg) { ret = pm_runtime_get_sync(ctrl->dev); if (ctrl->sched.clk_state != SLIM_CLK_ACTIVE) { dev_err(ctrl->dev, "ctrl wrong state:%d, ret:%d\n", ctrl->sched.clk_state, ret); goto slim_xfer_err; } } /* Initialize tid to invalid value */ txn->tid = 0; need_tid = slim_tid_txn(txn->mt, txn->mc); if (need_tid) { ret = slim_alloc_txn_tid(ctrl, txn); if (ret) return ret; if (!txn->msg->comp) txn->comp = &done; else txn->comp = txn->comp; } ret = ctrl->xfer_msg(ctrl, txn); if (!ret && need_tid && !txn->msg->comp) { unsigned long ms = txn->rl + HZ; timeout = wait_for_completion_timeout(txn->comp, msecs_to_jiffies(ms)); if (!timeout) { ret = -ETIMEDOUT; slim_free_txn_tid(ctrl, txn); } } if (ret) dev_err(ctrl->dev, "Tx:MT:0x%x, MC:0x%x, LA:0x%x failed:%d\n", txn->mt, txn->mc, txn->la, ret); slim_xfer_err: if (!clk_pause_msg && (txn->tid == 0 || ret == -ETIMEDOUT)) { /* * remove runtime-pm vote if this was TX only, or * if there was error during this transaction */ pm_runtime_mark_last_busy(ctrl->dev); pm_runtime_put_autosuspend(ctrl->dev); } return ret; } EXPORT_SYMBOL_GPL(slim_do_transfer); static int slim_val_inf_sanity(struct slim_controller *ctrl, struct slim_val_inf *msg, u8 mc) { if (!msg || msg->num_bytes > 16 || (msg->start_offset + msg->num_bytes) > 0xC00) goto reterr; switch (mc) { case SLIM_MSG_MC_REQUEST_VALUE: case SLIM_MSG_MC_REQUEST_INFORMATION: if (msg->rbuf != NULL) return 0; break; case SLIM_MSG_MC_CHANGE_VALUE: case SLIM_MSG_MC_CLEAR_INFORMATION: if (msg->wbuf != NULL) return 0; break; case SLIM_MSG_MC_REQUEST_CHANGE_VALUE: case SLIM_MSG_MC_REQUEST_CLEAR_INFORMATION: if (msg->rbuf != NULL && msg->wbuf != NULL) return 0; break; } reterr: if (msg) dev_err(ctrl->dev, "Sanity check failed:msg:offset:0x%x, mc:%d\n", msg->start_offset, mc); return -EINVAL; } static u16 slim_slicesize(int code) { static const u8 sizetocode[16] = { 0, 1, 2, 3, 3, 4, 4, 5, 5, 5, 5, 6, 6, 6, 6, 7 }; code = clamp(code, 1, (int)ARRAY_SIZE(sizetocode)); return sizetocode[code - 1]; } /** * slim_xfer_msg() - Transfer a value info message on slim device * * @sbdev: slim device to which this msg has to be transfered * @msg: value info message pointer * @mc: message code of the message * * Called by drivers which want to transfer a vlaue or info elements. * * Return: -ETIMEDOUT: If transmission of this message timed out */ int slim_xfer_msg(struct slim_device *sbdev, struct slim_val_inf *msg, u8 mc) { DEFINE_SLIM_LDEST_TXN(txn_stack, mc, 6, sbdev->laddr, msg); struct slim_msg_txn *txn = &txn_stack; struct slim_controller *ctrl = sbdev->ctrl; int ret; u16 sl; if (!ctrl) return -EINVAL; ret = slim_val_inf_sanity(ctrl, msg, mc); if (ret) return ret; sl = slim_slicesize(msg->num_bytes); dev_dbg(ctrl->dev, "SB xfer msg:os:%x, len:%d, MC:%x, sl:%x\n", msg->start_offset, msg->num_bytes, mc, sl); txn->ec = ((sl | (1 << 3)) | ((msg->start_offset & 0xFFF) << 4)); switch (mc) { case SLIM_MSG_MC_REQUEST_CHANGE_VALUE: case SLIM_MSG_MC_CHANGE_VALUE: case SLIM_MSG_MC_REQUEST_CLEAR_INFORMATION: case SLIM_MSG_MC_CLEAR_INFORMATION: txn->rl += msg->num_bytes; default: break; } if (slim_tid_txn(txn->mt, txn->mc)) txn->rl++; return slim_do_transfer(ctrl, txn); } EXPORT_SYMBOL_GPL(slim_xfer_msg); static void slim_fill_msg(struct slim_val_inf *msg, u32 addr, size_t count, u8 *rbuf, u8 *wbuf) { msg->start_offset = addr; msg->num_bytes = count; msg->rbuf = rbuf; msg->wbuf = wbuf; msg->comp = NULL; } /** * slim_read() - Read SLIMbus value element * * @sdev: client handle. * @addr: address of value element to read. * @count: number of bytes to read. Maximum bytes allowed are 16. * @val: will return what the value element value was * * Return: -EINVAL for Invalid parameters, -ETIMEDOUT If transmission of * this message timed out (e.g. due to bus lines not being clocked * or driven by controller) */ int slim_read(struct slim_device *sdev, u32 addr, size_t count, u8 *val) { struct slim_val_inf msg; slim_fill_msg(&msg, addr, count, val, NULL); return slim_xfer_msg(sdev, &msg, SLIM_MSG_MC_REQUEST_VALUE); } EXPORT_SYMBOL_GPL(slim_read); /** * slim_readb() - Read byte from SLIMbus value element * * @sdev: client handle. * @addr: address in the value element to read. * * Return: byte value of value element. */ int slim_readb(struct slim_device *sdev, u32 addr) { int ret; u8 buf; ret = slim_read(sdev, addr, 1, &buf); if (ret < 0) return ret; else return buf; } EXPORT_SYMBOL_GPL(slim_readb); /** * slim_write() - Write SLIMbus value element * * @sdev: client handle. * @addr: address in the value element to write. * @count: number of bytes to write. Maximum bytes allowed are 16. * @val: value to write to value element * * Return: -EINVAL for Invalid parameters, -ETIMEDOUT If transmission of * this message timed out (e.g. due to bus lines not being clocked * or driven by controller) */ int slim_write(struct slim_device *sdev, u32 addr, size_t count, u8 *val) { struct slim_val_inf msg; slim_fill_msg(&msg, addr, count, NULL, val); return slim_xfer_msg(sdev, &msg, SLIM_MSG_MC_CHANGE_VALUE); } EXPORT_SYMBOL_GPL(slim_write); /** * slim_writeb() - Write byte to SLIMbus value element * * @sdev: client handle. * @addr: address of value element to write. * @value: value to write to value element * * Return: -EINVAL for Invalid parameters, -ETIMEDOUT If transmission of * this message timed out (e.g. due to bus lines not being clocked * or driven by controller) * */ int slim_writeb(struct slim_device *sdev, u32 addr, u8 value) { return slim_write(sdev, addr, 1, &value); } EXPORT_SYMBOL_GPL(slim_writeb);