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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/slimbus/messaging.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/slimbus/messaging.c')
-rw-r--r-- | drivers/slimbus/messaging.c | 365 |
1 files changed, 365 insertions, 0 deletions
diff --git a/drivers/slimbus/messaging.c b/drivers/slimbus/messaging.c new file mode 100644 index 000000000..4ce0cb61e --- /dev/null +++ b/drivers/slimbus/messaging.c @@ -0,0 +1,365 @@ +// 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() - Free 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. transmitting 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; + break; + 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); |