diff options
Diffstat (limited to 'drivers/firmware/arm_scmi/driver.c')
| -rw-r--r-- | drivers/firmware/arm_scmi/driver.c | 728 |
1 files changed, 653 insertions, 75 deletions
diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c index b406b3f78f46..f818d00bb2c6 100644 --- a/drivers/firmware/arm_scmi/driver.c +++ b/drivers/firmware/arm_scmi/driver.c @@ -19,6 +19,7 @@ #include <linux/export.h> #include <linux/idr.h> #include <linux/io.h> +#include <linux/io-64-nonatomic-hi-lo.h> #include <linux/kernel.h> #include <linux/ktime.h> #include <linux/hashtable.h> @@ -60,6 +61,11 @@ static atomic_t transfer_last_id; static DEFINE_IDR(scmi_requested_devices); static DEFINE_MUTEX(scmi_requested_devices_mtx); +/* Track globally the creation of SCMI SystemPower related devices */ +static bool scmi_syspower_registered; +/* Protect access to scmi_syspower_registered */ +static DEFINE_MUTEX(scmi_syspower_mtx); + struct scmi_requested_dev { const struct scmi_device_id *id_table; struct list_head node; @@ -128,9 +134,16 @@ struct scmi_protocol_instance { * usage. * @protocols_mtx: A mutex to protect protocols instances initialization. * @protocols_imp: List of protocols implemented, currently maximum of - * MAX_PROTOCOLS_IMP elements allocated by the base protocol + * scmi_revision_info.num_protocols elements allocated by the + * base protocol * @active_protocols: IDR storing device_nodes for protocols actually defined * in the DT and confirmed as implemented by fw. + * @atomic_threshold: Optional system wide DT-configured threshold, expressed + * in microseconds, for atomic operations. + * Only SCMI synchronous commands reported by the platform + * to have an execution latency lesser-equal to the threshold + * should be considered for atomic mode operation: such + * decision is finally left up to the SCMI drivers. * @notify_priv: Pointer to private data structure specific to notifications. * @node: List head * @users: Number of users of this instance @@ -149,6 +162,7 @@ struct scmi_info { struct mutex protocols_mtx; u8 *protocols_imp; struct idr active_protocols; + unsigned int atomic_threshold; void *notify_priv; struct list_head node; int users; @@ -609,6 +623,25 @@ static inline void scmi_clear_channel(struct scmi_info *info, info->desc->ops->clear_channel(cinfo); } +static inline bool is_polling_required(struct scmi_chan_info *cinfo, + struct scmi_info *info) +{ + return cinfo->no_completion_irq || info->desc->force_polling; +} + +static inline bool is_transport_polling_capable(struct scmi_info *info) +{ + return info->desc->ops->poll_done || + info->desc->sync_cmds_completed_on_ret; +} + +static inline bool is_polling_enabled(struct scmi_chan_info *cinfo, + struct scmi_info *info) +{ + return is_polling_required(cinfo, info) && + is_transport_polling_capable(info); +} + static void scmi_handle_notification(struct scmi_chan_info *cinfo, u32 msg_hdr, void *priv) { @@ -629,9 +662,15 @@ static void scmi_handle_notification(struct scmi_chan_info *cinfo, unpack_scmi_header(msg_hdr, &xfer->hdr); if (priv) - xfer->priv = priv; + /* Ensure order between xfer->priv store and following ops */ + smp_store_mb(xfer->priv, priv); info->desc->ops->fetch_notification(cinfo, info->desc->max_msg_size, xfer); + + trace_scmi_msg_dump(xfer->hdr.protocol_id, xfer->hdr.id, "NOTI", + xfer->hdr.seq, xfer->hdr.status, + xfer->rx.buf, xfer->rx.len); + scmi_notify(cinfo->handle, xfer->hdr.protocol_id, xfer->hdr.id, xfer->rx.buf, xfer->rx.len, ts); @@ -652,7 +691,8 @@ static void scmi_handle_response(struct scmi_chan_info *cinfo, xfer = scmi_xfer_command_acquire(cinfo, msg_hdr); if (IS_ERR(xfer)) { - scmi_clear_channel(info, cinfo); + if (MSG_XTRACT_TYPE(msg_hdr) == MSG_TYPE_DELAYED_RESP) + scmi_clear_channel(info, cinfo); return; } @@ -661,9 +701,16 @@ static void scmi_handle_response(struct scmi_chan_info *cinfo, xfer->rx.len = info->desc->max_msg_size; if (priv) - xfer->priv = priv; + /* Ensure order between xfer->priv store and following ops */ + smp_store_mb(xfer->priv, priv); info->desc->ops->fetch_response(cinfo, xfer); + trace_scmi_msg_dump(xfer->hdr.protocol_id, xfer->hdr.id, + xfer->hdr.type == MSG_TYPE_DELAYED_RESP ? + "DLYD" : "RESP", + xfer->hdr.seq, xfer->hdr.status, + xfer->rx.buf, xfer->rx.len); + trace_scmi_rx_done(xfer->transfer_id, xfer->hdr.id, xfer->hdr.protocol_id, xfer->hdr.seq, xfer->hdr.type); @@ -724,8 +771,6 @@ static void xfer_put(const struct scmi_protocol_handle *ph, __scmi_xfer_put(&info->tx_minfo, xfer); } -#define SCMI_MAX_POLL_TO_NS (100 * NSEC_PER_USEC) - static bool scmi_xfer_done_no_timeout(struct scmi_chan_info *cinfo, struct scmi_xfer *xfer, ktime_t stop) { @@ -741,6 +786,85 @@ static bool scmi_xfer_done_no_timeout(struct scmi_chan_info *cinfo, } /** + * scmi_wait_for_message_response - An helper to group all the possible ways of + * waiting for a synchronous message response. + * + * @cinfo: SCMI channel info + * @xfer: Reference to the transfer being waited for. + * + * Chooses waiting strategy (sleep-waiting vs busy-waiting) depending on + * configuration flags like xfer->hdr.poll_completion. + * + * Return: 0 on Success, error otherwise. + */ +static int scmi_wait_for_message_response(struct scmi_chan_info *cinfo, + struct scmi_xfer *xfer) +{ + struct scmi_info *info = handle_to_scmi_info(cinfo->handle); + struct device *dev = info->dev; + int ret = 0, timeout_ms = info->desc->max_rx_timeout_ms; + + trace_scmi_xfer_response_wait(xfer->transfer_id, xfer->hdr.id, + xfer->hdr.protocol_id, xfer->hdr.seq, + timeout_ms, + xfer->hdr.poll_completion); + + if (xfer->hdr.poll_completion) { + /* + * Real polling is needed only if transport has NOT declared + * itself to support synchronous commands replies. + */ + if (!info->desc->sync_cmds_completed_on_ret) { + /* + * Poll on xfer using transport provided .poll_done(); + * assumes no completion interrupt was available. + */ + ktime_t stop = ktime_add_ms(ktime_get(), timeout_ms); + + spin_until_cond(scmi_xfer_done_no_timeout(cinfo, + xfer, stop)); + if (ktime_after(ktime_get(), stop)) { + dev_err(dev, + "timed out in resp(caller: %pS) - polling\n", + (void *)_RET_IP_); + ret = -ETIMEDOUT; + } + } + + if (!ret) { + unsigned long flags; + + /* + * Do not fetch_response if an out-of-order delayed + * response is being processed. + */ + spin_lock_irqsave(&xfer->lock, flags); + if (xfer->state == SCMI_XFER_SENT_OK) { + info->desc->ops->fetch_response(cinfo, xfer); + xfer->state = SCMI_XFER_RESP_OK; + } + spin_unlock_irqrestore(&xfer->lock, flags); + + /* Trace polled replies. */ + trace_scmi_msg_dump(xfer->hdr.protocol_id, xfer->hdr.id, + "RESP", + xfer->hdr.seq, xfer->hdr.status, + xfer->rx.buf, xfer->rx.len); + } + } else { + /* And we wait for the response. */ + if (!wait_for_completion_timeout(&xfer->done, + msecs_to_jiffies(timeout_ms))) { + dev_err(dev, "timed out in resp(caller: %pS)\n", + (void *)_RET_IP_); + ret = -ETIMEDOUT; + } + } + + return ret; +} + +/** * do_xfer() - Do one transfer * * @ph: Pointer to SCMI protocol handle @@ -754,18 +878,26 @@ static int do_xfer(const struct scmi_protocol_handle *ph, struct scmi_xfer *xfer) { int ret; - int timeout; const struct scmi_protocol_instance *pi = ph_to_pi(ph); struct scmi_info *info = handle_to_scmi_info(pi->handle); struct device *dev = info->dev; struct scmi_chan_info *cinfo; - if (xfer->hdr.poll_completion && !info->desc->ops->poll_done) { + /* Check for polling request on custom command xfers at first */ + if (xfer->hdr.poll_completion && !is_transport_polling_capable(info)) { dev_warn_once(dev, "Polling mode is not supported by transport.\n"); return -EINVAL; } + cinfo = idr_find(&info->tx_idr, pi->proto->id); + if (unlikely(!cinfo)) + return -EINVAL; + + /* True ONLY if also supported by transport. */ + if (is_polling_enabled(cinfo, info)) + xfer->hdr.poll_completion = true; + /* * Initialise protocol id now from protocol handle to avoid it being * overridden by mistake (or malice) by the protocol code mangling with @@ -774,10 +906,6 @@ static int do_xfer(const struct scmi_protocol_handle *ph, xfer->hdr.protocol_id = pi->proto->id; reinit_completion(&xfer->done); - cinfo = idr_find(&info->tx_idr, xfer->hdr.protocol_id); - if (unlikely(!cinfo)) - return -EINVAL; - trace_scmi_xfer_begin(xfer->transfer_id, xfer->hdr.id, xfer->hdr.protocol_id, xfer->hdr.seq, xfer->hdr.poll_completion); @@ -798,41 +926,16 @@ static int do_xfer(const struct scmi_protocol_handle *ph, return ret; } - if (xfer->hdr.poll_completion) { - ktime_t stop = ktime_add_ns(ktime_get(), SCMI_MAX_POLL_TO_NS); - - spin_until_cond(scmi_xfer_done_no_timeout(cinfo, xfer, stop)); - if (ktime_before(ktime_get(), stop)) { - unsigned long flags; - - /* - * Do not fetch_response if an out-of-order delayed - * response is being processed. - */ - spin_lock_irqsave(&xfer->lock, flags); - if (xfer->state == SCMI_XFER_SENT_OK) { - info->desc->ops->fetch_response(cinfo, xfer); - xfer->state = SCMI_XFER_RESP_OK; - } - spin_unlock_irqrestore(&xfer->lock, flags); - } else { - ret = -ETIMEDOUT; - } - } else { - /* And we wait for the response. */ - timeout = msecs_to_jiffies(info->desc->max_rx_timeout_ms); - if (!wait_for_completion_timeout(&xfer->done, timeout)) { - dev_err(dev, "timed out in resp(caller: %pS)\n", - (void *)_RET_IP_); - ret = -ETIMEDOUT; - } - } + trace_scmi_msg_dump(xfer->hdr.protocol_id, xfer->hdr.id, "CMND", + xfer->hdr.seq, xfer->hdr.status, + xfer->tx.buf, xfer->tx.len); + ret = scmi_wait_for_message_response(cinfo, xfer); if (!ret && xfer->hdr.status) ret = scmi_to_linux_errno(xfer->hdr.status); if (info->desc->ops->mark_txdone) - info->desc->ops->mark_txdone(cinfo, ret); + info->desc->ops->mark_txdone(cinfo, ret, xfer); trace_scmi_xfer_end(xfer->transfer_id, xfer->hdr.id, xfer->hdr.protocol_id, xfer->hdr.seq, ret); @@ -858,6 +961,20 @@ static void reset_rx_to_maxsz(const struct scmi_protocol_handle *ph, * @ph: Pointer to SCMI protocol handle * @xfer: Transfer to initiate and wait for response * + * Using asynchronous commands in atomic/polling mode should be avoided since + * it could cause long busy-waiting here, so ignore polling for the delayed + * response and WARN if it was requested for this command transaction since + * upper layers should refrain from issuing such kind of requests. + * + * The only other option would have been to refrain from using any asynchronous + * command even if made available, when an atomic transport is detected, and + * instead forcibly use the synchronous version (thing that can be easily + * attained at the protocol layer), but this would also have led to longer + * stalls of the channel for synchronous commands and possibly timeouts. + * (in other words there is usually a good reason if a platform provides an + * asynchronous version of a command and we should prefer to use it...just not + * when using atomic/polling mode) + * * Return: -ETIMEDOUT in case of no delayed response, if transmit error, * return corresponding error, else if all goes well, return 0. */ @@ -869,12 +986,24 @@ static int do_xfer_with_response(const struct scmi_protocol_handle *ph, xfer->async_done = &async_response; + /* + * Delayed responses should not be polled, so an async command should + * not have been used when requiring an atomic/poll context; WARN and + * perform instead a sleeping wait. + * (Note Async + IgnoreDelayedResponses are sent via do_xfer) + */ + WARN_ON_ONCE(xfer->hdr.poll_completion); + ret = do_xfer(ph, xfer); if (!ret) { - if (!wait_for_completion_timeout(xfer->async_done, timeout)) + if (!wait_for_completion_timeout(xfer->async_done, timeout)) { + dev_err(ph->dev, + "timed out in delayed resp(caller: %pS)\n", + (void *)_RET_IP_); ret = -ETIMEDOUT; - else if (xfer->hdr.status) + } else if (xfer->hdr.status) { ret = scmi_to_linux_errno(xfer->hdr.status); + } } xfer->async_done = NULL; @@ -1001,6 +1130,332 @@ static const struct scmi_xfer_ops xfer_ops = { .xfer_put = xfer_put, }; +struct scmi_msg_resp_domain_name_get { + __le32 flags; + u8 name[SCMI_MAX_STR_SIZE]; +}; + +/** + * scmi_common_extended_name_get - Common helper to get extended resources name + * @ph: A protocol handle reference. + * @cmd_id: The specific command ID to use. + * @res_id: The specific resource ID to use. + * @name: A pointer to the preallocated area where the retrieved name will be + * stored as a NULL terminated string. + * @len: The len in bytes of the @name char array. + * + * Return: 0 on Succcess + */ +static int scmi_common_extended_name_get(const struct scmi_protocol_handle *ph, + u8 cmd_id, u32 res_id, char *name, + size_t len) +{ + int ret; + struct scmi_xfer *t; + struct scmi_msg_resp_domain_name_get *resp; + + ret = ph->xops->xfer_get_init(ph, cmd_id, sizeof(res_id), + sizeof(*resp), &t); + if (ret) + goto out; + + put_unaligned_le32(res_id, t->tx.buf); + resp = t->rx.buf; + + ret = ph->xops->do_xfer(ph, t); + if (!ret) + strscpy(name, resp->name, len); + + ph->xops->xfer_put(ph, t); +out: + if (ret) + dev_warn(ph->dev, + "Failed to get extended name - id:%u (ret:%d). Using %s\n", + res_id, ret, name); + return ret; +} + +/** + * struct scmi_iterator - Iterator descriptor + * @msg: A reference to the message TX buffer; filled by @prepare_message with + * a proper custom command payload for each multi-part command request. + * @resp: A reference to the response RX buffer; used by @update_state and + * @process_response to parse the multi-part replies. + * @t: A reference to the underlying xfer initialized and used transparently by + * the iterator internal routines. + * @ph: A reference to the associated protocol handle to be used. + * @ops: A reference to the custom provided iterator operations. + * @state: The current iterator state; used and updated in turn by the iterators + * internal routines and by the caller-provided @scmi_iterator_ops. + * @priv: A reference to optional private data as provided by the caller and + * passed back to the @@scmi_iterator_ops. + */ +struct scmi_iterator { + void *msg; + void *resp; + struct scmi_xfer *t; + const struct scmi_protocol_handle *ph; + struct scmi_iterator_ops *ops; + struct scmi_iterator_state state; + void *priv; +}; + +static void *scmi_iterator_init(const struct scmi_protocol_handle *ph, + struct scmi_iterator_ops *ops, + unsigned int max_resources, u8 msg_id, + size_t tx_size, void *priv) +{ + int ret; + struct scmi_iterator *i; + + i = devm_kzalloc(ph->dev, sizeof(*i), GFP_KERNEL); + if (!i) + return ERR_PTR(-ENOMEM); + + i->ph = ph; + i->ops = ops; + i->priv = priv; + + ret = ph->xops->xfer_get_init(ph, msg_id, tx_size, 0, &i->t); + if (ret) { + devm_kfree(ph->dev, i); + return ERR_PTR(ret); + } + + i->state.max_resources = max_resources; + i->msg = i->t->tx.buf; + i->resp = i->t->rx.buf; + + return i; +} + +static int scmi_iterator_run(void *iter) +{ + int ret = -EINVAL; + struct scmi_iterator_ops *iops; + const struct scmi_protocol_handle *ph; + struct scmi_iterator_state *st; + struct scmi_iterator *i = iter; + + if (!i || !i->ops || !i->ph) + return ret; + + iops = i->ops; + ph = i->ph; + st = &i->state; + + do { + iops->prepare_message(i->msg, st->desc_index, i->priv); + ret = ph->xops->do_xfer(ph, i->t); + if (ret) + break; + + st->rx_len = i->t->rx.len; + ret = iops->update_state(st, i->resp, i->priv); + if (ret) + break; + + if (st->num_returned > st->max_resources - st->desc_index) { + dev_err(ph->dev, + "No. of resources can't exceed %d\n", + st->max_resources); + ret = -EINVAL; + break; + } + + for (st->loop_idx = 0; st->loop_idx < st->num_returned; + st->loop_idx++) { + ret = iops->process_response(ph, i->resp, st, i->priv); + if (ret) + goto out; + } + + st->desc_index += st->num_returned; + ph->xops->reset_rx_to_maxsz(ph, i->t); + /* + * check for both returned and remaining to avoid infinite + * loop due to buggy firmware + */ + } while (st->num_returned && st->num_remaining); + +out: + /* Finalize and destroy iterator */ + ph->xops->xfer_put(ph, i->t); + devm_kfree(ph->dev, i); + + return ret; +} + +struct scmi_msg_get_fc_info { + __le32 domain; + __le32 message_id; +}; + +struct scmi_msg_resp_desc_fc { + __le32 attr; +#define SUPPORTS_DOORBELL(x) ((x) & BIT(0)) +#define DOORBELL_REG_WIDTH(x) FIELD_GET(GENMASK(2, 1), (x)) + __le32 rate_limit; + __le32 chan_addr_low; + __le32 chan_addr_high; + __le32 chan_size; + __le32 db_addr_low; + __le32 db_addr_high; + __le32 db_set_lmask; + __le32 db_set_hmask; + __le32 db_preserve_lmask; + __le32 db_preserve_hmask; +}; + +static void +scmi_common_fastchannel_init(const struct scmi_protocol_handle *ph, + u8 describe_id, u32 message_id, u32 valid_size, + u32 domain, void __iomem **p_addr, + struct scmi_fc_db_info **p_db) +{ + int ret; + u32 flags; + u64 phys_addr; + u8 size; + void __iomem *addr; + struct scmi_xfer *t; + struct scmi_fc_db_info *db = NULL; + struct scmi_msg_get_fc_info *info; + struct scmi_msg_resp_desc_fc *resp; + const struct scmi_protocol_instance *pi = ph_to_pi(ph); + + if (!p_addr) { + ret = -EINVAL; + goto err_out; + } + + ret = ph->xops->xfer_get_init(ph, describe_id, + sizeof(*info), sizeof(*resp), &t); + if (ret) + goto err_out; + + info = t->tx.buf; + info->domain = cpu_to_le32(domain); + info->message_id = cpu_to_le32(message_id); + + /* + * Bail out on error leaving fc_info addresses zeroed; this includes + * the case in which the requested domain/message_id does NOT support + * fastchannels at all. + */ + ret = ph->xops->do_xfer(ph, t); + if (ret) + goto err_xfer; + + resp = t->rx.buf; + flags = le32_to_cpu(resp->attr); + size = le32_to_cpu(resp->chan_size); + if (size != valid_size) { + ret = -EINVAL; + goto err_xfer; + } + + phys_addr = le32_to_cpu(resp->chan_addr_low); + phys_addr |= (u64)le32_to_cpu(resp->chan_addr_high) << 32; + addr = devm_ioremap(ph->dev, phys_addr, size); + if (!addr) { + ret = -EADDRNOTAVAIL; + goto err_xfer; + } + + *p_addr = addr; + + if (p_db && SUPPORTS_DOORBELL(flags)) { + db = devm_kzalloc(ph->dev, sizeof(*db), GFP_KERNEL); + if (!db) { + ret = -ENOMEM; + goto err_db; + } + + size = 1 << DOORBELL_REG_WIDTH(flags); + phys_addr = le32_to_cpu(resp->db_addr_low); + phys_addr |= (u64)le32_to_cpu(resp->db_addr_high) << 32; + addr = devm_ioremap(ph->dev, phys_addr, size); + if (!addr) { + ret = -EADDRNOTAVAIL; + goto err_db_mem; + } + + db->addr = addr; + db->width = size; + db->set = le32_to_cpu(resp->db_set_lmask); + db->set |= (u64)le32_to_cpu(resp->db_set_hmask) << 32; + db->mask = le32_to_cpu(resp->db_preserve_lmask); + db->mask |= (u64)le32_to_cpu(resp->db_preserve_hmask) << 32; + + *p_db = db; + } + + ph->xops->xfer_put(ph, t); + + dev_dbg(ph->dev, + "Using valid FC for protocol %X [MSG_ID:%u / RES_ID:%u]\n", + pi->proto->id, message_id, domain); + + return; + +err_db_mem: + devm_kfree(ph->dev, db); + +err_db: + *p_addr = NULL; + +err_xfer: + ph->xops->xfer_put(ph, t); + +err_out: + dev_warn(ph->dev, + "Failed to get FC for protocol %X [MSG_ID:%u / RES_ID:%u] - ret:%d. Using regular messaging.\n", + pi->proto->id, message_id, domain, ret); +} + +#define SCMI_PROTO_FC_RING_DB(w) \ +do { \ + u##w val = 0; \ + \ + if (db->mask) \ + val = ioread##w(db->addr) & db->mask; \ + iowrite##w((u##w)db->set | val, db->addr); \ +} while (0) + +static void scmi_common_fastchannel_db_ring(struct scmi_fc_db_info *db) +{ + if (!db || !db->addr) + return; + + if (db->width == 1) + SCMI_PROTO_FC_RING_DB(8); + else if (db->width == 2) + SCMI_PROTO_FC_RING_DB(16); + else if (db->width == 4) + SCMI_PROTO_FC_RING_DB(32); + else /* db->width == 8 */ +#ifdef CONFIG_64BIT + SCMI_PROTO_FC_RING_DB(64); +#else + { + u64 val = 0; + + if (db->mask) + val = ioread64_hi_lo(db->addr) & db->mask; + iowrite64_hi_lo(db->set | val, db->addr); + } +#endif +} + +static const struct scmi_proto_helpers_ops helpers_ops = { + .extended_name_get = scmi_common_extended_name_get, + .iter_response_init = scmi_iterator_init, + .iter_response_run = scmi_iterator_run, + .fastchannel_init = scmi_common_fastchannel_init, + .fastchannel_db_ring = scmi_common_fastchannel_db_ring, +}; + /** * scmi_revision_area_get - Retrieve version memory area. * @@ -1061,6 +1516,7 @@ scmi_alloc_init_protocol_instance(struct scmi_info *info, pi->handle = handle; pi->ph.dev = handle->dev; pi->ph.xops = &xfer_ops; + pi->ph.hops = &helpers_ops; pi->ph.set_priv = scmi_set_protocol_priv; pi->ph.get_priv = scmi_get_protocol_priv; refcount_set(&pi->users, 1); @@ -1209,11 +1665,12 @@ scmi_is_protocol_implemented(const struct scmi_handle *handle, u8 prot_id) { int i; struct scmi_info *info = handle_to_scmi_info(handle); + struct scmi_revision_info *rev = handle->version; if (!info->protocols_imp) return false; - for (i = 0; i < MAX_PROTOCOLS_IMP; i++) + for (i = 0; i < rev->num_protocols; i++) if (info->protocols_imp[i] == prot_id) return true; return false; @@ -1231,6 +1688,30 @@ static void scmi_devm_release_protocol(struct device *dev, void *res) scmi_protocol_release(dres->handle, dres->protocol_id); } +static struct scmi_protocol_instance __must_check * +scmi_devres_protocol_instance_get(struct scmi_device *sdev, u8 protocol_id) +{ + struct scmi_protocol_instance *pi; + struct scmi_protocol_devres *dres; + + dres = devres_alloc(scmi_devm_release_protocol, + sizeof(*dres), GFP_KERNEL); + if (!dres) + return ERR_PTR(-ENOMEM); + + pi = scmi_get_protocol_instance(sdev->handle, protocol_id); + if (IS_ERR(pi)) { + devres_free(dres); + return pi; + } + + dres->handle = sdev->handle; + dres->protocol_id = protocol_id; + devres_add(&sdev->dev, dres); + + return pi; +} + /** * scmi_devm_protocol_get - Devres managed get protocol operations and handle * @sdev: A reference to an scmi_device whose embedded struct device is to @@ -1254,32 +1735,47 @@ scmi_devm_protocol_get(struct scmi_device *sdev, u8 protocol_id, struct scmi_protocol_handle **ph) { struct scmi_protocol_instance *pi; - struct scmi_protocol_devres *dres; - struct scmi_handle *handle = sdev->handle; if (!ph) return ERR_PTR(-EINVAL); - dres = devres_alloc(scmi_devm_release_protocol, - sizeof(*dres), GFP_KERNEL); - if (!dres) - return ERR_PTR(-ENOMEM); - - pi = scmi_get_protocol_instance(handle, protocol_id); - if (IS_ERR(pi)) { - devres_free(dres); + pi = scmi_devres_protocol_instance_get(sdev, protocol_id); + if (IS_ERR(pi)) return pi; - } - - dres->handle = handle; - dres->protocol_id = protocol_id; - devres_add(&sdev->dev, dres); *ph = &pi->ph; return pi->proto->ops; } +/** + * scmi_devm_protocol_acquire - Devres managed helper to get hold of a protocol + * @sdev: A reference to an scmi_device whose embedded struct device is to + * be used for devres accounting. + * @protocol_id: The protocol being requested. + * + * Get hold of a protocol accounting for its usage, possibly triggering its + * initialization but without getting access to its protocol specific operations + * and handle. + * + * Being a devres based managed method, protocol hold will be automatically + * released, and possibly de-initialized on last user, once the SCMI driver + * owning the scmi_device is unbound from it. + * + * Return: 0 on SUCCESS + */ +static int __must_check scmi_devm_protocol_acquire(struct scmi_device *sdev, + u8 protocol_id) +{ + struct scmi_protocol_instance *pi; + + pi = scmi_devres_protocol_instance_get(sdev, protocol_id); + if (IS_ERR(pi)) + return PTR_ERR(pi); + + return 0; +} + static int scmi_devm_protocol_match(struct device *dev, void *res, void *data) { struct scmi_protocol_devres *dres = res; @@ -1308,6 +1804,29 @@ static void scmi_devm_protocol_put(struct scmi_device *sdev, u8 protocol_id) WARN_ON(ret); } +/** + * scmi_is_transport_atomic - Method to check if underlying transport for an + * SCMI instance is configured as atomic. + * + * @handle: A reference to the SCMI platform instance. + * @atomic_threshold: An optional return value for the system wide currently + * configured threshold for atomic operations. + * + * Return: True if transport is configured as atomic + */ +static bool scmi_is_transport_atomic(const struct scmi_handle *handle, + unsigned int *atomic_threshold) +{ + bool ret; + struct scmi_info *info = handle_to_scmi_info(handle); + + ret = info->desc->atomic_enabled && is_transport_polling_capable(info); + if (ret && atomic_threshold) + *atomic_threshold = info->atomic_threshold; + + return ret; +} + static inline struct scmi_handle *scmi_handle_get_from_info_unlocked(struct scmi_info *info) { @@ -1494,11 +2013,22 @@ static int scmi_chan_setup(struct scmi_info *info, struct device *dev, return -ENOMEM; cinfo->dev = dev; + cinfo->rx_timeout_ms = info->desc->max_rx_timeout_ms; ret = info->desc->ops->chan_setup(cinfo, info->dev, tx); if (ret) return ret; + if (tx && is_polling_required(cinfo, info)) { + if (is_transport_polling_capable(info)) + dev_info(dev, + "Enabled polling mode TX channel - prot_id:%d\n", + prot_id); + else + dev_warn(dev, + "Polling mode NOT supported by transport.\n"); + } + idr_alloc: ret = idr_alloc(idr, cinfo, prot_id, prot_id + 1, GFP_KERNEL); if (ret != prot_id) { @@ -1515,8 +2045,12 @@ scmi_txrx_setup(struct scmi_info *info, struct device *dev, int prot_id) { int ret = scmi_chan_setup(info, dev, prot_id, true); - if (!ret) /* Rx is optional, hence no error check */ - scmi_chan_setup(info, dev, prot_id, false); + if (!ret) { + /* Rx is optional, report only memory errors */ + ret = scmi_chan_setup(info, dev, prot_id, false); + if (ret && ret != -ENOMEM) + ret = 0; + } return ret; } @@ -1550,21 +2084,39 @@ scmi_get_protocol_device(struct device_node *np, struct scmi_info *info, if (sdev) return sdev; + mutex_lock(&scmi_syspower_mtx); + if (prot_id == SCMI_PROTOCOL_SYSTEM && scmi_syspower_registered) { + dev_warn(info->dev, + "SCMI SystemPower protocol device must be unique !\n"); + mutex_unlock(&scmi_syspower_mtx); + + return NULL; + } + pr_debug("Creating SCMI device (%s) for protocol %x\n", name, prot_id); sdev = scmi_device_create(np, info->dev, prot_id, name); if (!sdev) { dev_err(info->dev, "failed to create %d protocol device\n", prot_id); + mutex_unlock(&scmi_syspower_mtx); + return NULL; } if (scmi_txrx_setup(info, &sdev->dev, prot_id)) { dev_err(&sdev->dev, "failed to setup transport\n"); scmi_device_destroy(sdev); + mutex_unlock(&scmi_syspower_mtx); + return NULL; } + if (prot_id == SCMI_PROTOCOL_SYSTEM) + scmi_syspower_registered = true; + + mutex_unlock(&scmi_syspower_mtx); + return sdev; } @@ -1726,10 +2278,16 @@ int scmi_protocol_device_request(const struct scmi_device_id *id_table) sdev = scmi_get_protocol_device(child, info, id_table->protocol_id, id_table->name); - /* Set handle if not already set: device existed */ - if (sdev && !sdev->handle) - sdev->handle = - scmi_handle_get_from_info_unlocked(info); + if (sdev) { + /* Set handle if not already set: device existed */ + if (!sdev->handle) + sdev->handle = + scmi_handle_get_from_info_unlocked(info); + /* Relink consumer and suppliers */ + if (sdev->handle) + scmi_device_link_add(&sdev->dev, + sdev->handle->dev); + } } else { dev_err(info->dev, "Failed. SCMI protocol %d not active.\n", @@ -1833,9 +2391,18 @@ static int scmi_probe(struct platform_device *pdev) handle = &info->handle; handle->dev = info->dev; handle->version = &info->version; + handle->devm_protocol_acquire = scmi_devm_protocol_acquire; handle->devm_protocol_get = scmi_devm_protocol_get; handle->devm_protocol_put = scmi_devm_protocol_put; + /* System wide atomic threshold for atomic ops .. if any */ + if (!of_property_read_u32(np, "atomic-threshold-us", + &info->atomic_threshold)) + dev_info(dev, + "SCMI System wide atomic threshold set to %d us\n", + info->atomic_threshold); + handle->is_transport_atomic = scmi_is_transport_atomic; + if (desc->ops->link_supplier) { ret = desc->ops->link_supplier(dev); if (ret) @@ -1853,6 +2420,10 @@ static int scmi_probe(struct platform_device *pdev) if (scmi_notification_init(handle)) dev_err(dev, "SCMI Notifications NOT available.\n"); + if (info->desc->atomic_enabled && !is_transport_polling_capable(info)) + dev_err(dev, + "Transport is not polling capable. Atomic mode not supported.\n"); + /* * Trigger SCMI Base protocol initialization. * It's mandatory and won't be ever released/deinit until the @@ -1915,20 +2486,17 @@ void scmi_free_channel(struct scmi_chan_info *cinfo, struct idr *idr, int id) static int scmi_remove(struct platform_device *pdev) { - int ret = 0, id; + int ret, id; struct scmi_info *info = platform_get_drvdata(pdev); struct device_node *child; mutex_lock(&scmi_list_mutex); if (info->users) - ret = -EBUSY; - else - list_del(&info->node); + dev_warn(&pdev->dev, + "Still active SCMI users will be forcibly unbound.\n"); + list_del(&info->node); mutex_unlock(&scmi_list_mutex); - if (ret) - return ret; - scmi_notification_exit(&info->handle); mutex_lock(&info->protocols_mtx); @@ -1940,7 +2508,11 @@ static int scmi_remove(struct platform_device *pdev) idr_destroy(&info->active_protocols); /* Safe to free channels since no more users */ - return scmi_cleanup_txrx_channels(info); + ret = scmi_cleanup_txrx_channels(info); + if (ret) + dev_warn(&pdev->dev, "Failed to cleanup SCMI channels.\n"); + + return 0; } static ssize_t protocol_version_show(struct device *dev, @@ -1994,6 +2566,9 @@ static const struct of_device_id scmi_of_match[] = { #ifdef CONFIG_ARM_SCMI_TRANSPORT_MAILBOX { .compatible = "arm,scmi", .data = &scmi_mailbox_desc }, #endif +#ifdef CONFIG_ARM_SCMI_TRANSPORT_OPTEE + { .compatible = "linaro,scmi-optee", .data = &scmi_optee_desc }, +#endif #ifdef CONFIG_ARM_SCMI_TRANSPORT_SMC { .compatible = "arm,scmi-smc", .data = &scmi_smc_desc}, #endif @@ -2008,6 +2583,7 @@ MODULE_DEVICE_TABLE(of, scmi_of_match); static struct platform_driver scmi_driver = { .driver = { .name = "arm-scmi", + .suppress_bind_attrs = true, .of_match_table = scmi_of_match, .dev_groups = versions_groups, }, @@ -2087,6 +2663,7 @@ static int __init scmi_driver_init(void) scmi_sensors_register(); scmi_voltage_register(); scmi_system_register(); + scmi_powercap_register(); return platform_driver_register(&scmi_driver); } @@ -2103,6 +2680,7 @@ static void __exit scmi_driver_exit(void) scmi_sensors_unregister(); scmi_voltage_unregister(); scmi_system_unregister(); + scmi_powercap_unregister(); scmi_bus_exit(); @@ -2112,7 +2690,7 @@ static void __exit scmi_driver_exit(void) } module_exit(scmi_driver_exit); -MODULE_ALIAS("platform: arm-scmi"); +MODULE_ALIAS("platform:arm-scmi"); MODULE_AUTHOR("Sudeep Holla <sudeep.holla@arm.com>"); MODULE_DESCRIPTION("ARM SCMI protocol driver"); MODULE_LICENSE("GPL v2"); |