xref: /openbmc/linux/drivers/hwtracing/intel_th/sth.c (revision 63705da3)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Intel(R) Trace Hub Software Trace Hub support
4  *
5  * Copyright (C) 2014-2015 Intel Corporation.
6  */
7 
8 #define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
9 
10 #include <linux/types.h>
11 #include <linux/module.h>
12 #include <linux/device.h>
13 #include <linux/io.h>
14 #include <linux/mm.h>
15 #include <linux/slab.h>
16 #include <linux/stm.h>
17 
18 #include "intel_th.h"
19 #include "sth.h"
20 
21 struct sth_device {
22 	void __iomem	*base;
23 	void __iomem	*channels;
24 	phys_addr_t	channels_phys;
25 	struct device	*dev;
26 	struct stm_data	stm;
27 	unsigned int	sw_nmasters;
28 };
29 
30 static struct intel_th_channel __iomem *
31 sth_channel(struct sth_device *sth, unsigned int master, unsigned int channel)
32 {
33 	struct intel_th_channel __iomem *sw_map = sth->channels;
34 
35 	return &sw_map[(master - sth->stm.sw_start) * sth->stm.sw_nchannels +
36 		       channel];
37 }
38 
39 static void sth_iowrite(void __iomem *dest, const unsigned char *payload,
40 			unsigned int size)
41 {
42 	switch (size) {
43 #ifdef CONFIG_64BIT
44 	case 8:
45 		writeq_relaxed(*(u64 *)payload, dest);
46 		break;
47 #endif
48 	case 4:
49 		writel_relaxed(*(u32 *)payload, dest);
50 		break;
51 	case 2:
52 		writew_relaxed(*(u16 *)payload, dest);
53 		break;
54 	case 1:
55 		writeb_relaxed(*(u8 *)payload, dest);
56 		break;
57 	default:
58 		break;
59 	}
60 }
61 
62 static ssize_t notrace sth_stm_packet(struct stm_data *stm_data,
63 				      unsigned int master,
64 				      unsigned int channel,
65 				      unsigned int packet,
66 				      unsigned int flags,
67 				      unsigned int size,
68 				      const unsigned char *payload)
69 {
70 	struct sth_device *sth = container_of(stm_data, struct sth_device, stm);
71 	struct intel_th_channel __iomem *out =
72 		sth_channel(sth, master, channel);
73 	u64 __iomem *outp = &out->Dn;
74 	unsigned long reg = REG_STH_TRIG;
75 
76 #ifndef CONFIG_64BIT
77 	if (size > 4)
78 		size = 4;
79 #endif
80 
81 	size = rounddown_pow_of_two(size);
82 
83 	switch (packet) {
84 	/* Global packets (GERR, XSYNC, TRIG) are sent with register writes */
85 	case STP_PACKET_GERR:
86 		reg += 4;
87 		fallthrough;
88 
89 	case STP_PACKET_XSYNC:
90 		reg += 8;
91 		fallthrough;
92 
93 	case STP_PACKET_TRIG:
94 		if (flags & STP_PACKET_TIMESTAMPED)
95 			reg += 4;
96 		writeb_relaxed(*payload, sth->base + reg);
97 		break;
98 
99 	case STP_PACKET_MERR:
100 		if (size > 4)
101 			size = 4;
102 
103 		sth_iowrite(&out->MERR, payload, size);
104 		break;
105 
106 	case STP_PACKET_FLAG:
107 		if (flags & STP_PACKET_TIMESTAMPED)
108 			outp = (u64 __iomem *)&out->FLAG_TS;
109 		else
110 			outp = (u64 __iomem *)&out->FLAG;
111 
112 		size = 0;
113 		writeb_relaxed(0, outp);
114 		break;
115 
116 	case STP_PACKET_USER:
117 		if (flags & STP_PACKET_TIMESTAMPED)
118 			outp = &out->USER_TS;
119 		else
120 			outp = &out->USER;
121 		sth_iowrite(outp, payload, size);
122 		break;
123 
124 	case STP_PACKET_DATA:
125 		outp = &out->Dn;
126 
127 		if (flags & STP_PACKET_TIMESTAMPED)
128 			outp += 2;
129 		if (flags & STP_PACKET_MARKED)
130 			outp++;
131 
132 		sth_iowrite(outp, payload, size);
133 		break;
134 	default:
135 		return -ENOTSUPP;
136 	}
137 
138 	return size;
139 }
140 
141 static phys_addr_t
142 sth_stm_mmio_addr(struct stm_data *stm_data, unsigned int master,
143 		  unsigned int channel, unsigned int nr_chans)
144 {
145 	struct sth_device *sth = container_of(stm_data, struct sth_device, stm);
146 	phys_addr_t addr;
147 
148 	master -= sth->stm.sw_start;
149 	addr = sth->channels_phys + (master * sth->stm.sw_nchannels + channel) *
150 		sizeof(struct intel_th_channel);
151 
152 	if (offset_in_page(addr) ||
153 	    offset_in_page(nr_chans * sizeof(struct intel_th_channel)))
154 		return 0;
155 
156 	return addr;
157 }
158 
159 static int sth_stm_link(struct stm_data *stm_data, unsigned int master,
160 			 unsigned int channel)
161 {
162 	struct sth_device *sth = container_of(stm_data, struct sth_device, stm);
163 
164 	return intel_th_set_output(to_intel_th_device(sth->dev), master);
165 }
166 
167 static int intel_th_sw_init(struct sth_device *sth)
168 {
169 	u32 reg;
170 
171 	reg = ioread32(sth->base + REG_STH_STHCAP1);
172 	sth->stm.sw_nchannels = reg & 0xff;
173 
174 	reg = ioread32(sth->base + REG_STH_STHCAP0);
175 	sth->stm.sw_start = reg & 0xffff;
176 	sth->stm.sw_end = reg >> 16;
177 
178 	sth->sw_nmasters = sth->stm.sw_end - sth->stm.sw_start;
179 	dev_dbg(sth->dev, "sw_start: %x sw_end: %x masters: %x nchannels: %x\n",
180 		sth->stm.sw_start, sth->stm.sw_end, sth->sw_nmasters,
181 		sth->stm.sw_nchannels);
182 
183 	return 0;
184 }
185 
186 static int intel_th_sth_probe(struct intel_th_device *thdev)
187 {
188 	struct device *dev = &thdev->dev;
189 	struct sth_device *sth;
190 	struct resource *res;
191 	void __iomem *base, *channels;
192 	int err;
193 
194 	res = intel_th_device_get_resource(thdev, IORESOURCE_MEM, 0);
195 	if (!res)
196 		return -ENODEV;
197 
198 	base = devm_ioremap(dev, res->start, resource_size(res));
199 	if (!base)
200 		return -ENOMEM;
201 
202 	res = intel_th_device_get_resource(thdev, IORESOURCE_MEM, 1);
203 	if (!res)
204 		return -ENODEV;
205 
206 	channels = devm_ioremap(dev, res->start, resource_size(res));
207 	if (!channels)
208 		return -ENOMEM;
209 
210 	sth = devm_kzalloc(dev, sizeof(*sth), GFP_KERNEL);
211 	if (!sth)
212 		return -ENOMEM;
213 
214 	sth->dev = dev;
215 	sth->base = base;
216 	sth->channels = channels;
217 	sth->channels_phys = res->start;
218 	sth->stm.name = dev_name(dev);
219 	sth->stm.packet = sth_stm_packet;
220 	sth->stm.mmio_addr = sth_stm_mmio_addr;
221 	sth->stm.sw_mmiosz = sizeof(struct intel_th_channel);
222 	sth->stm.link = sth_stm_link;
223 
224 	err = intel_th_sw_init(sth);
225 	if (err)
226 		return err;
227 
228 	err = stm_register_device(dev, &sth->stm, THIS_MODULE);
229 	if (err) {
230 		dev_err(dev, "stm_register_device failed\n");
231 		return err;
232 	}
233 
234 	dev_set_drvdata(dev, sth);
235 
236 	return 0;
237 }
238 
239 static void intel_th_sth_remove(struct intel_th_device *thdev)
240 {
241 	struct sth_device *sth = dev_get_drvdata(&thdev->dev);
242 
243 	stm_unregister_device(&sth->stm);
244 }
245 
246 static struct intel_th_driver intel_th_sth_driver = {
247 	.probe	= intel_th_sth_probe,
248 	.remove	= intel_th_sth_remove,
249 	.driver	= {
250 		.name	= "sth",
251 		.owner	= THIS_MODULE,
252 	},
253 };
254 
255 module_driver(intel_th_sth_driver,
256 	      intel_th_driver_register,
257 	      intel_th_driver_unregister);
258 
259 MODULE_LICENSE("GPL v2");
260 MODULE_DESCRIPTION("Intel(R) Trace Hub Software Trace Hub driver");
261 MODULE_AUTHOR("Alexander Shishkin <alexander.shishkin@intel.com>");
262