1 // SPDX-License-Identifier: GPL-2.0
17  * scp_ipi_register() - register an ipi function
22  * @priv:	private data for IPI handler
26  * Returns 0 if ipi registers successfully, -error on error.
34 		return -EPROBE_DEFER;  in scp_ipi_register()
37 		return -EINVAL;  in scp_ipi_register()
40 	scp->ipi_desc[id].handler = handler;  in scp_ipi_register()
41 	scp->ipi_desc[id].priv = priv;  in scp_ipi_register()
49  * scp_ipi_unregister() - unregister an ipi function
65 	scp->ipi_desc[id].handler = NULL;  in scp_ipi_unregister()
66 	scp->ipi_desc[id].priv = NULL;  in scp_ipi_unregister()
72  * scp_memcpy_aligned() - Copy src to dst, where dst is in SCP SRAM region.
78  * Since AP access of SCP SRAM don't support byte write, this always write a
90 		i = 4 - (dst - ptr);  in scp_memcpy_aligned()
92 		memcpy((u8 *)&val + (4 - i), src, i);  in scp_memcpy_aligned()
96 	__iowrite32_copy(dst + i, src + i, (len - i) / 4);  in scp_memcpy_aligned()
97 	remain = (len - i) % 4;  in scp_memcpy_aligned()
100 		val = readl_relaxed(dst + len - remain);  in scp_memcpy_aligned()
101 		memcpy(&val, src + len - remain, remain);  in scp_memcpy_aligned()
102 		writel_relaxed(val, dst + len - remain);  in scp_memcpy_aligned()
108  * scp_ipi_lock() - Lock before operations of an IPI ID
119 	mutex_lock(&scp->ipi_desc[id].lock);  in scp_ipi_lock()
124  * scp_ipi_lock() - Unlock after operations of an IPI ID
135 	mutex_unlock(&scp->ipi_desc[id].lock);  in scp_ipi_unlock()
140  * scp_ipi_send() - send data from AP to scp.
146  * @wait:	number of msecs to wait for ack. 0 to skip waiting.
148  * This function is thread-safe. When this function returns,
153  * Returns 0 if sending data successfully, -error on error.
156 		 unsigned int wait)  in scp_ipi_send()  argument
158 	struct mtk_share_obj __iomem *send_obj = scp->send_buf;  in scp_ipi_send()
164 	    WARN_ON(len > sizeof(send_obj->share_buf)) || WARN_ON(!buf))  in scp_ipi_send()
165 		return -EINVAL;  in scp_ipi_send()
167 	mutex_lock(&scp->send_lock);  in scp_ipi_send()
169 	ret = clk_prepare_enable(scp->clk);  in scp_ipi_send()
171 		dev_err(scp->dev, "failed to enable clock\n");  in scp_ipi_send()
175 	 /* Wait until SCP receives the last command */  in scp_ipi_send()
179 			dev_err(scp->dev, "%s: IPI timeout!\n", __func__);  in scp_ipi_send()
180 			ret = -ETIMEDOUT;  in scp_ipi_send()
183 	} while (readl(scp->reg_base + scp->data->host_to_scp_reg));  in scp_ipi_send()
185 	scp_memcpy_aligned(send_obj->share_buf, buf, len);  in scp_ipi_send()
187 	writel(len, &send_obj->len);  in scp_ipi_send()
188 	writel(id, &send_obj->id);  in scp_ipi_send()
190 	scp->ipi_id_ack[id] = false;  in scp_ipi_send()
192 	writel(scp->data->host_to_scp_int_bit,  in scp_ipi_send()
193 	       scp->reg_base + scp->data->host_to_scp_reg);  in scp_ipi_send()
195 	if (wait) {  in scp_ipi_send()
196 		/* wait for SCP's ACK */  in scp_ipi_send()
197 		timeout = msecs_to_jiffies(wait);  in scp_ipi_send()
198 		ret = wait_event_timeout(scp->ack_wq,  in scp_ipi_send()
199 					 scp->ipi_id_ack[id],  in scp_ipi_send()
201 		scp->ipi_id_ack[id] = false;  in scp_ipi_send()
202 		if (WARN(!ret, "scp ipi %d ack time out !", id))  in scp_ipi_send()
203 			ret = -EIO;  in scp_ipi_send()
209 	clk_disable_unprepare(scp->clk);  in scp_ipi_send()
211 	mutex_unlock(&scp->send_lock);  in scp_ipi_send()