xref: /linux/drivers/interconnect/qcom/smd-rpm.c (revision 1fd1dc41724319406b0aff221a352a400b0ddfc5)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * RPM over SMD communication wrapper for interconnects
4  *
5  * Copyright (C) 2019 Linaro Ltd
6  * Author: Georgi Djakov <georgi.djakov@linaro.org>
7  */
8 
9 #include <linux/interconnect-provider.h>
10 #include <linux/module.h>
11 #include <linux/platform_device.h>
12 #include <linux/soc/qcom/smd-rpm.h>
13 
14 #include "icc-rpm.h"
15 
16 #define RPM_KEY_BW		0x00007762
17 
18 static struct qcom_smd_rpm *icc_smd_rpm;
19 
20 struct icc_rpm_smd_req {
21 	__le32 key;
22 	__le32 nbytes;
23 	__le32 value;
24 };
25 
26 bool qcom_icc_rpm_smd_available(void)
27 {
28 	return !!icc_smd_rpm;
29 }
30 EXPORT_SYMBOL_GPL(qcom_icc_rpm_smd_available);
31 
32 int qcom_icc_rpm_smd_send(int ctx, int rsc_type, int id, u32 val)
33 {
34 	struct icc_rpm_smd_req req = {
35 		.key = cpu_to_le32(RPM_KEY_BW),
36 		.nbytes = cpu_to_le32(sizeof(u32)),
37 		.value = cpu_to_le32(val),
38 	};
39 
40 	return qcom_rpm_smd_write(icc_smd_rpm, ctx, rsc_type, id, &req,
41 				  sizeof(req));
42 }
43 EXPORT_SYMBOL_GPL(qcom_icc_rpm_smd_send);
44 
45 int qcom_icc_rpm_set_bus_rate(const struct rpm_clk_resource *clk, int ctx, u32 rate)
46 {
47 	struct clk_smd_rpm_req req = {
48 		.key = cpu_to_le32(QCOM_RPM_SMD_KEY_RATE),
49 		.nbytes = cpu_to_le32(sizeof(u32)),
50 	};
51 
52 	/* Branch clocks are only on/off */
53 	if (clk->branch)
54 		rate = !!rate;
55 
56 	req.value = cpu_to_le32(rate);
57 	return qcom_rpm_smd_write(icc_smd_rpm,
58 				  ctx,
59 				  clk->resource_type,
60 				  clk->clock_id,
61 				  &req, sizeof(req));
62 }
63 EXPORT_SYMBOL_GPL(qcom_icc_rpm_set_bus_rate);
64 
65 static void qcom_icc_rpm_smd_remove(struct platform_device *pdev)
66 {
67 	icc_smd_rpm = NULL;
68 }
69 
70 static int qcom_icc_rpm_smd_probe(struct platform_device *pdev)
71 {
72 	icc_smd_rpm = dev_get_drvdata(pdev->dev.parent);
73 
74 	if (!icc_smd_rpm) {
75 		dev_err(&pdev->dev, "unable to retrieve handle to RPM\n");
76 		return -ENODEV;
77 	}
78 
79 	return 0;
80 }
81 
82 static struct platform_driver qcom_interconnect_rpm_smd_driver = {
83 	.driver = {
84 		.name		= "icc_smd_rpm",
85 	},
86 	.probe = qcom_icc_rpm_smd_probe,
87 	.remove = qcom_icc_rpm_smd_remove,
88 };
89 module_platform_driver(qcom_interconnect_rpm_smd_driver);
90 MODULE_AUTHOR("Georgi Djakov <georgi.djakov@linaro.org>");
91 MODULE_DESCRIPTION("Qualcomm SMD RPM interconnect proxy driver");
92 MODULE_LICENSE("GPL v2");
93 MODULE_ALIAS("platform:icc_smd_rpm");
94