1 // SPDX-License-Identifier: GPL-2.0
3  * System Control and Management Interface (SCMI) Message SMC/HVC
9 #include <linux/arm-smccc.h>
26  * The shmem address is split into 4K page and offset.
29  * This however limits the shmem address to 44 bit.
32  * scmi instances that are using the same smc-id.
40 #define SHMEM_OFFSET(x) ((x) & (SHMEM_SIZE - 1))
43  * struct scmi_smc - Structure representing a SCMI smc transport
46  * @cinfo: SCMI channel info
47  * @shmem: Transmit/Receive shared memory area
54  * @param_page: 4K page number of the shmem channel
55  * @param_offset: Offset within the 4K page of the shmem channel
63 	struct scmi_shared_mem __iomem *shmem;  member
65 	/* Protect access to shmem area */
81 	core->rx_callback(scmi_info->cinfo,  in smc_msg_done_isr()
82 			  core->shmem->read_header(scmi_info->shmem), NULL);  in smc_msg_done_isr()
90 					of_parse_phandle(of_node, "shmem", 0);  in smc_chan_available()
100 		atomic_set(&scmi_info->inflight, INFLIGHT_NONE);  in smc_channel_lock_init()
102 		mutex_init(&scmi_info->shmem_lock);  in smc_channel_lock_init()
109 	ret = atomic_cmpxchg(inflight, INFLIGHT_NONE, xfer->hdr.seq);  in smc_xfer_inflight()
119 		spin_until_cond(smc_xfer_inflight(xfer, &scmi_info->inflight));  in smc_channel_lock_acquire()
121 		mutex_lock(&scmi_info->shmem_lock);  in smc_channel_lock_acquire()
127 		atomic_set(&scmi_info->inflight, INFLIGHT_NONE);  in smc_channel_lock_release()
129 		mutex_unlock(&scmi_info->shmem_lock);  in smc_channel_lock_release()
135 	struct device *cdev = cinfo->dev;  in smc_chan_setup()
143 		return -ENODEV;  in smc_chan_setup()
147 		return -ENOMEM;  in smc_chan_setup()
149 	scmi_info->shmem = core->shmem->setup_iomap(cinfo, dev, tx, &res,  in smc_chan_setup()
150 						    &scmi_info->io_ops);  in smc_chan_setup()
151 	if (IS_ERR(scmi_info->shmem))  in smc_chan_setup()
152 		return PTR_ERR(scmi_info->shmem);  in smc_chan_setup()
154 	ret = of_property_read_u32(dev->of_node, "arm,smc-id", &func_id);  in smc_chan_setup()
158 	if (of_device_is_compatible(dev->of_node, "qcom,scmi-smc")) {  in smc_chan_setup()
160 		void __iomem *ptr = (void __iomem *)scmi_info->shmem + size - 8;  in smc_chan_setup()
161 		/* The capability-id is kept in last 8 bytes of shmem.  in smc_chan_setup()
162 		 *     +-------+ <-- 0  in smc_chan_setup()
163 		 *     | shmem |  in smc_chan_setup()
164 		 *     +-------+ <-- size - 8  in smc_chan_setup()
166 		 *     +-------+ <-- size  in smc_chan_setup()
171 	if (of_device_is_compatible(dev->of_node, "arm,scmi-smc-param")) {  in smc_chan_setup()
172 		scmi_info->param_page = SHMEM_PAGE(res.start);  in smc_chan_setup()
173 		scmi_info->param_offset = SHMEM_OFFSET(res.start);  in smc_chan_setup()
180 	scmi_info->irq = of_irq_get_byname(cdev->of_node, "a2p");  in smc_chan_setup()
181 	if (scmi_info->irq > 0) {  in smc_chan_setup()
182 		ret = request_irq(scmi_info->irq, smc_msg_done_isr,  in smc_chan_setup()
185 			dev_err(dev, "failed to setup SCMI smc irq\n");  in smc_chan_setup()
189 		cinfo->no_completion_irq = true;  in smc_chan_setup()
192 	scmi_info->func_id = func_id;  in smc_chan_setup()
193 	scmi_info->cap_id = cap_id;  in smc_chan_setup()
194 	scmi_info->cinfo = cinfo;  in smc_chan_setup()
196 	cinfo->transport_info = scmi_info;  in smc_chan_setup()
204 	struct scmi_smc *scmi_info = cinfo->transport_info;  in smc_chan_free()
214 	if (scmi_info->irq > 0)  in smc_chan_free()
215 		free_irq(scmi_info->irq, scmi_info);  in smc_chan_free()
217 	cinfo->transport_info = NULL;  in smc_chan_free()
218 	scmi_info->cinfo = NULL;  in smc_chan_free()
226 	struct scmi_smc *scmi_info = cinfo->transport_info;  in smc_send_message()
235 	core->shmem->tx_prepare(scmi_info->shmem, xfer, cinfo,  in smc_send_message()
236 				scmi_info->io_ops->toio);  in smc_send_message()
238 	if (scmi_info->cap_id != ULONG_MAX)  in smc_send_message()
239 		arm_smccc_1_1_invoke(scmi_info->func_id, scmi_info->cap_id, 0,  in smc_send_message()
242 		arm_smccc_1_1_invoke(scmi_info->func_id, scmi_info->param_page,  in smc_send_message()
243 				     scmi_info->param_offset, 0, 0, 0, 0, 0,  in smc_send_message()
249 		return -EOPNOTSUPP;  in smc_send_message()
258 	struct scmi_smc *scmi_info = cinfo->transport_info;  in smc_fetch_response()
260 	core->shmem->fetch_response(scmi_info->shmem, xfer,  in smc_fetch_response()
261 				    scmi_info->io_ops->fromio);  in smc_fetch_response()
267 	struct scmi_smc *scmi_info = cinfo->transport_info;  in smc_mark_txdone()
289 	 * SCMI command would have been already fully processed by the SCMI
299 	{ .compatible = "arm,scmi-smc" },
300 	{ .compatible = "arm,scmi-smc-param" },
301 	{ .compatible = "qcom,scmi-smc" },
312 MODULE_DESCRIPTION("SCMI SMC Transport driver");