xref: /openbmc/linux/drivers/hwtracing/intel_th/sth.c (revision b78412b8)
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 notrace sth_stm_packet(struct stm_data *stm_data,
71 				      unsigned int master,
72 				      unsigned int channel,
73 				      unsigned int packet,
74 				      unsigned int flags,
75 				      unsigned int size,
76 				      const unsigned char *payload)
77 {
78 	struct sth_device *sth = container_of(stm_data, struct sth_device, stm);
79 	struct intel_th_channel __iomem *out =
80 		sth_channel(sth, master, channel);
81 	u64 __iomem *outp = &out->Dn;
82 	unsigned long reg = REG_STH_TRIG;
83 
84 #ifndef CONFIG_64BIT
85 	if (size > 4)
86 		size = 4;
87 #endif
88 
89 	size = rounddown_pow_of_two(size);
90 
91 	switch (packet) {
92 	/* Global packets (GERR, XSYNC, TRIG) are sent with register writes */
93 	case STP_PACKET_GERR:
94 		reg += 4;
95 	case STP_PACKET_XSYNC:
96 		reg += 8;
97 	case STP_PACKET_TRIG:
98 		if (flags & STP_PACKET_TIMESTAMPED)
99 			reg += 4;
100 		writeb_relaxed(*payload, sth->base + reg);
101 		break;
102 
103 	case STP_PACKET_MERR:
104 		if (size > 4)
105 			size = 4;
106 
107 		sth_iowrite(&out->MERR, payload, size);
108 		break;
109 
110 	case STP_PACKET_FLAG:
111 		if (flags & STP_PACKET_TIMESTAMPED)
112 			outp = (u64 __iomem *)&out->FLAG_TS;
113 		else
114 			outp = (u64 __iomem *)&out->FLAG;
115 
116 		size = 0;
117 		writeb_relaxed(0, outp);
118 		break;
119 
120 	case STP_PACKET_USER:
121 		if (flags & STP_PACKET_TIMESTAMPED)
122 			outp = &out->USER_TS;
123 		else
124 			outp = &out->USER;
125 		sth_iowrite(outp, payload, size);
126 		break;
127 
128 	case STP_PACKET_DATA:
129 		outp = &out->Dn;
130 
131 		if (flags & STP_PACKET_TIMESTAMPED)
132 			outp += 2;
133 		if (flags & STP_PACKET_MARKED)
134 			outp++;
135 
136 		sth_iowrite(outp, payload, size);
137 		break;
138 	default:
139 		return -ENOTSUPP;
140 	}
141 
142 	return size;
143 }
144 
145 static phys_addr_t
146 sth_stm_mmio_addr(struct stm_data *stm_data, unsigned int master,
147 		  unsigned int channel, unsigned int nr_chans)
148 {
149 	struct sth_device *sth = container_of(stm_data, struct sth_device, stm);
150 	phys_addr_t addr;
151 
152 	master -= sth->stm.sw_start;
153 	addr = sth->channels_phys + (master * sth->stm.sw_nchannels + channel) *
154 		sizeof(struct intel_th_channel);
155 
156 	if (offset_in_page(addr) ||
157 	    offset_in_page(nr_chans * sizeof(struct intel_th_channel)))
158 		return 0;
159 
160 	return addr;
161 }
162 
163 static int sth_stm_link(struct stm_data *stm_data, unsigned int master,
164 			 unsigned int channel)
165 {
166 	struct sth_device *sth = container_of(stm_data, struct sth_device, stm);
167 
168 	intel_th_set_output(to_intel_th_device(sth->dev), master);
169 
170 	return 0;
171 }
172 
173 static int intel_th_sw_init(struct sth_device *sth)
174 {
175 	u32 reg;
176 
177 	reg = ioread32(sth->base + REG_STH_STHCAP1);
178 	sth->stm.sw_nchannels = reg & 0xff;
179 
180 	reg = ioread32(sth->base + REG_STH_STHCAP0);
181 	sth->stm.sw_start = reg & 0xffff;
182 	sth->stm.sw_end = reg >> 16;
183 
184 	sth->sw_nmasters = sth->stm.sw_end - sth->stm.sw_start;
185 	dev_dbg(sth->dev, "sw_start: %x sw_end: %x masters: %x nchannels: %x\n",
186 		sth->stm.sw_start, sth->stm.sw_end, sth->sw_nmasters,
187 		sth->stm.sw_nchannels);
188 
189 	return 0;
190 }
191 
192 static int intel_th_sth_probe(struct intel_th_device *thdev)
193 {
194 	struct device *dev = &thdev->dev;
195 	struct sth_device *sth;
196 	struct resource *res;
197 	void __iomem *base, *channels;
198 	int err;
199 
200 	res = intel_th_device_get_resource(thdev, IORESOURCE_MEM, 0);
201 	if (!res)
202 		return -ENODEV;
203 
204 	base = devm_ioremap(dev, res->start, resource_size(res));
205 	if (!base)
206 		return -ENOMEM;
207 
208 	res = intel_th_device_get_resource(thdev, IORESOURCE_MEM, 1);
209 	if (!res)
210 		return -ENODEV;
211 
212 	channels = devm_ioremap(dev, res->start, resource_size(res));
213 	if (!channels)
214 		return -ENOMEM;
215 
216 	sth = devm_kzalloc(dev, sizeof(*sth), GFP_KERNEL);
217 	if (!sth)
218 		return -ENOMEM;
219 
220 	sth->dev = dev;
221 	sth->base = base;
222 	sth->channels = channels;
223 	sth->channels_phys = res->start;
224 	sth->stm.name = dev_name(dev);
225 	sth->stm.packet = sth_stm_packet;
226 	sth->stm.mmio_addr = sth_stm_mmio_addr;
227 	sth->stm.sw_mmiosz = sizeof(struct intel_th_channel);
228 	sth->stm.link = sth_stm_link;
229 
230 	err = intel_th_sw_init(sth);
231 	if (err)
232 		return err;
233 
234 	err = stm_register_device(dev, &sth->stm, THIS_MODULE);
235 	if (err) {
236 		dev_err(dev, "stm_register_device failed\n");
237 		return err;
238 	}
239 
240 	dev_set_drvdata(dev, sth);
241 
242 	return 0;
243 }
244 
245 static void intel_th_sth_remove(struct intel_th_device *thdev)
246 {
247 	struct sth_device *sth = dev_get_drvdata(&thdev->dev);
248 
249 	stm_unregister_device(&sth->stm);
250 }
251 
252 static struct intel_th_driver intel_th_sth_driver = {
253 	.probe	= intel_th_sth_probe,
254 	.remove	= intel_th_sth_remove,
255 	.driver	= {
256 		.name	= "sth",
257 		.owner	= THIS_MODULE,
258 	},
259 };
260 
261 module_driver(intel_th_sth_driver,
262 	      intel_th_driver_register,
263 	      intel_th_driver_unregister);
264 
265 MODULE_LICENSE("GPL v2");
266 MODULE_DESCRIPTION("Intel(R) Trace Hub Software Trace Hub driver");
267 MODULE_AUTHOR("Alexander Shishkin <alexander.shishkin@intel.com>");
268