xref: /linux/drivers/hwtracing/intel_th/sth.c (revision c0c914eca7f251c70facc37dfebeaf176601918d)
1 /*
2  * Intel(R) Trace Hub Software Trace Hub support
3  *
4  * Copyright (C) 2014-2015 Intel Corporation.
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms and conditions of the GNU General Public License,
8  * version 2, as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope it will be useful, but WITHOUT
11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
13  * more details.
14  */
15 
16 #define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
17 
18 #include <linux/types.h>
19 #include <linux/module.h>
20 #include <linux/device.h>
21 #include <linux/io.h>
22 #include <linux/mm.h>
23 #include <linux/slab.h>
24 #include <linux/stm.h>
25 
26 #include "intel_th.h"
27 #include "sth.h"
28 
29 struct sth_device {
30 	void __iomem	*base;
31 	void __iomem	*channels;
32 	phys_addr_t	channels_phys;
33 	struct device	*dev;
34 	struct stm_data	stm;
35 	unsigned int	sw_nmasters;
36 };
37 
38 static struct intel_th_channel __iomem *
39 sth_channel(struct sth_device *sth, unsigned int master, unsigned int channel)
40 {
41 	struct intel_th_channel __iomem *sw_map = sth->channels;
42 
43 	return &sw_map[(master - sth->stm.sw_start) * sth->stm.sw_nchannels +
44 		       channel];
45 }
46 
47 static void sth_iowrite(void __iomem *dest, const unsigned char *payload,
48 			unsigned int size)
49 {
50 	switch (size) {
51 #ifdef CONFIG_64BIT
52 	case 8:
53 		writeq_relaxed(*(u64 *)payload, dest);
54 		break;
55 #endif
56 	case 4:
57 		writel_relaxed(*(u32 *)payload, dest);
58 		break;
59 	case 2:
60 		writew_relaxed(*(u16 *)payload, dest);
61 		break;
62 	case 1:
63 		writeb_relaxed(*(u8 *)payload, dest);
64 		break;
65 	default:
66 		break;
67 	}
68 }
69 
70 static ssize_t sth_stm_packet(struct stm_data *stm_data, unsigned int master,
71 			      unsigned int channel, unsigned int packet,
72 			      unsigned int flags, unsigned int size,
73 			      const unsigned char *payload)
74 {
75 	struct sth_device *sth = container_of(stm_data, struct sth_device, stm);
76 	struct intel_th_channel __iomem *out =
77 		sth_channel(sth, master, channel);
78 	u64 __iomem *outp = &out->Dn;
79 	unsigned long reg = REG_STH_TRIG;
80 
81 #ifndef CONFIG_64BIT
82 	if (size > 4)
83 		size = 4;
84 #endif
85 
86 	size = rounddown_pow_of_two(size);
87 
88 	switch (packet) {
89 	/* Global packets (GERR, XSYNC, TRIG) are sent with register writes */
90 	case STP_PACKET_GERR:
91 		reg += 4;
92 	case STP_PACKET_XSYNC:
93 		reg += 8;
94 	case STP_PACKET_TRIG:
95 		if (flags & STP_PACKET_TIMESTAMPED)
96 			reg += 4;
97 		iowrite8(*payload, sth->base + reg);
98 		break;
99 
100 	case STP_PACKET_MERR:
101 		sth_iowrite(&out->MERR, payload, size);
102 		break;
103 
104 	case STP_PACKET_FLAG:
105 		if (flags & STP_PACKET_TIMESTAMPED)
106 			outp = (u64 __iomem *)&out->FLAG_TS;
107 		else
108 			outp = (u64 __iomem *)&out->FLAG;
109 
110 		size = 1;
111 		sth_iowrite(outp, payload, size);
112 		break;
113 
114 	case STP_PACKET_USER:
115 		if (flags & STP_PACKET_TIMESTAMPED)
116 			outp = &out->USER_TS;
117 		else
118 			outp = &out->USER;
119 		sth_iowrite(outp, payload, size);
120 		break;
121 
122 	case STP_PACKET_DATA:
123 		outp = &out->Dn;
124 
125 		if (flags & STP_PACKET_TIMESTAMPED)
126 			outp += 2;
127 		if (flags & STP_PACKET_MARKED)
128 			outp++;
129 
130 		sth_iowrite(outp, payload, size);
131 		break;
132 	}
133 
134 	return size;
135 }
136 
137 static phys_addr_t
138 sth_stm_mmio_addr(struct stm_data *stm_data, unsigned int master,
139 		  unsigned int channel, unsigned int nr_chans)
140 {
141 	struct sth_device *sth = container_of(stm_data, struct sth_device, stm);
142 	phys_addr_t addr;
143 
144 	master -= sth->stm.sw_start;
145 	addr = sth->channels_phys + (master * sth->stm.sw_nchannels + channel) *
146 		sizeof(struct intel_th_channel);
147 
148 	if (offset_in_page(addr) ||
149 	    offset_in_page(nr_chans * sizeof(struct intel_th_channel)))
150 		return 0;
151 
152 	return addr;
153 }
154 
155 static int sth_stm_link(struct stm_data *stm_data, unsigned int master,
156 			 unsigned int channel)
157 {
158 	struct sth_device *sth = container_of(stm_data, struct sth_device, stm);
159 
160 	intel_th_set_output(to_intel_th_device(sth->dev), master);
161 
162 	return 0;
163 }
164 
165 static int intel_th_sw_init(struct sth_device *sth)
166 {
167 	u32 reg;
168 
169 	reg = ioread32(sth->base + REG_STH_STHCAP1);
170 	sth->stm.sw_nchannels = reg & 0xff;
171 
172 	reg = ioread32(sth->base + REG_STH_STHCAP0);
173 	sth->stm.sw_start = reg & 0xffff;
174 	sth->stm.sw_end = reg >> 16;
175 
176 	sth->sw_nmasters = sth->stm.sw_end - sth->stm.sw_start;
177 	dev_dbg(sth->dev, "sw_start: %x sw_end: %x masters: %x nchannels: %x\n",
178 		sth->stm.sw_start, sth->stm.sw_end, sth->sw_nmasters,
179 		sth->stm.sw_nchannels);
180 
181 	return 0;
182 }
183 
184 static int intel_th_sth_probe(struct intel_th_device *thdev)
185 {
186 	struct device *dev = &thdev->dev;
187 	struct sth_device *sth;
188 	struct resource *res;
189 	void __iomem *base, *channels;
190 	int err;
191 
192 	res = intel_th_device_get_resource(thdev, IORESOURCE_MEM, 0);
193 	if (!res)
194 		return -ENODEV;
195 
196 	base = devm_ioremap(dev, res->start, resource_size(res));
197 	if (!base)
198 		return -ENOMEM;
199 
200 	res = intel_th_device_get_resource(thdev, IORESOURCE_MEM, 1);
201 	if (!res)
202 		return -ENODEV;
203 
204 	channels = devm_ioremap(dev, res->start, resource_size(res));
205 	if (!channels)
206 		return -ENOMEM;
207 
208 	sth = devm_kzalloc(dev, sizeof(*sth), GFP_KERNEL);
209 	if (!sth)
210 		return -ENOMEM;
211 
212 	sth->dev = dev;
213 	sth->base = base;
214 	sth->channels = channels;
215 	sth->channels_phys = res->start;
216 	sth->stm.name = dev_name(dev);
217 	sth->stm.packet = sth_stm_packet;
218 	sth->stm.mmio_addr = sth_stm_mmio_addr;
219 	sth->stm.sw_mmiosz = sizeof(struct intel_th_channel);
220 	sth->stm.link = sth_stm_link;
221 
222 	err = intel_th_sw_init(sth);
223 	if (err)
224 		return err;
225 
226 	err = stm_register_device(dev, &sth->stm, THIS_MODULE);
227 	if (err) {
228 		dev_err(dev, "stm_register_device failed\n");
229 		return err;
230 	}
231 
232 	dev_set_drvdata(dev, sth);
233 
234 	return 0;
235 }
236 
237 static void intel_th_sth_remove(struct intel_th_device *thdev)
238 {
239 	struct sth_device *sth = dev_get_drvdata(&thdev->dev);
240 
241 	stm_unregister_device(&sth->stm);
242 }
243 
244 static struct intel_th_driver intel_th_sth_driver = {
245 	.probe	= intel_th_sth_probe,
246 	.remove	= intel_th_sth_remove,
247 	.driver	= {
248 		.name	= "sth",
249 		.owner	= THIS_MODULE,
250 	},
251 };
252 
253 module_driver(intel_th_sth_driver,
254 	      intel_th_driver_register,
255 	      intel_th_driver_unregister);
256 
257 MODULE_LICENSE("GPL v2");
258 MODULE_DESCRIPTION("Intel(R) Trace Hub Software Trace Hub driver");
259 MODULE_AUTHOR("Alexander Shishkin <alexander.shishkin@intel.com>");
260