cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

gth.c (21203B)


      1// SPDX-License-Identifier: GPL-2.0
      2/*
      3 * Intel(R) Trace Hub Global Trace Hub
      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/bitmap.h>
     17#include <linux/pm_runtime.h>
     18
     19#include "intel_th.h"
     20#include "gth.h"
     21
     22struct gth_device;
     23
     24/**
     25 * struct gth_output - GTH view on an output port
     26 * @gth:	backlink to the GTH device
     27 * @output:	link to output device's output descriptor
     28 * @index:	output port number
     29 * @port_type:	one of GTH_* port type values
     30 * @master:	bitmap of masters configured for this output
     31 */
     32struct gth_output {
     33	struct gth_device	*gth;
     34	struct intel_th_output	*output;
     35	unsigned int		index;
     36	unsigned int		port_type;
     37	DECLARE_BITMAP(master, TH_CONFIGURABLE_MASTERS + 1);
     38};
     39
     40/**
     41 * struct gth_device - GTH device
     42 * @dev:	driver core's device
     43 * @base:	register window base address
     44 * @output_group:	attributes describing output ports
     45 * @master_group:	attributes describing master assignments
     46 * @output:		output ports
     47 * @master:		master/output port assignments
     48 * @gth_lock:		serializes accesses to GTH bits
     49 */
     50struct gth_device {
     51	struct device		*dev;
     52	void __iomem		*base;
     53
     54	struct attribute_group	output_group;
     55	struct attribute_group	master_group;
     56	struct gth_output	output[TH_POSSIBLE_OUTPUTS];
     57	signed char		master[TH_CONFIGURABLE_MASTERS + 1];
     58	spinlock_t		gth_lock;
     59};
     60
     61static void gth_output_set(struct gth_device *gth, int port,
     62			   unsigned int config)
     63{
     64	unsigned long reg = port & 4 ? REG_GTH_GTHOPT1 : REG_GTH_GTHOPT0;
     65	u32 val;
     66	int shift = (port & 3) * 8;
     67
     68	val = ioread32(gth->base + reg);
     69	val &= ~(0xff << shift);
     70	val |= config << shift;
     71	iowrite32(val, gth->base + reg);
     72}
     73
     74static unsigned int gth_output_get(struct gth_device *gth, int port)
     75{
     76	unsigned long reg = port & 4 ? REG_GTH_GTHOPT1 : REG_GTH_GTHOPT0;
     77	u32 val;
     78	int shift = (port & 3) * 8;
     79
     80	val = ioread32(gth->base + reg);
     81	val &= 0xff << shift;
     82	val >>= shift;
     83
     84	return val;
     85}
     86
     87static void gth_smcfreq_set(struct gth_device *gth, int port,
     88			    unsigned int freq)
     89{
     90	unsigned long reg = REG_GTH_SMCR0 + ((port / 2) * 4);
     91	int shift = (port & 1) * 16;
     92	u32 val;
     93
     94	val = ioread32(gth->base + reg);
     95	val &= ~(0xffff << shift);
     96	val |= freq << shift;
     97	iowrite32(val, gth->base + reg);
     98}
     99
    100static unsigned int gth_smcfreq_get(struct gth_device *gth, int port)
    101{
    102	unsigned long reg = REG_GTH_SMCR0 + ((port / 2) * 4);
    103	int shift = (port & 1) * 16;
    104	u32 val;
    105
    106	val = ioread32(gth->base + reg);
    107	val &= 0xffff << shift;
    108	val >>= shift;
    109
    110	return val;
    111}
    112
    113/*
    114 * "masters" attribute group
    115 */
    116
    117struct master_attribute {
    118	struct device_attribute	attr;
    119	struct gth_device	*gth;
    120	unsigned int		master;
    121};
    122
    123static void
    124gth_master_set(struct gth_device *gth, unsigned int master, int port)
    125{
    126	unsigned int reg = REG_GTH_SWDEST0 + ((master >> 1) & ~3u);
    127	unsigned int shift = (master & 0x7) * 4;
    128	u32 val;
    129
    130	if (master >= 256) {
    131		reg = REG_GTH_GSWTDEST;
    132		shift = 0;
    133	}
    134
    135	val = ioread32(gth->base + reg);
    136	val &= ~(0xf << shift);
    137	if (port >= 0)
    138		val |= (0x8 | port) << shift;
    139	iowrite32(val, gth->base + reg);
    140}
    141
    142static ssize_t master_attr_show(struct device *dev,
    143				struct device_attribute *attr,
    144				char *buf)
    145{
    146	struct master_attribute *ma =
    147		container_of(attr, struct master_attribute, attr);
    148	struct gth_device *gth = ma->gth;
    149	size_t count;
    150	int port;
    151
    152	spin_lock(&gth->gth_lock);
    153	port = gth->master[ma->master];
    154	spin_unlock(&gth->gth_lock);
    155
    156	if (port >= 0)
    157		count = snprintf(buf, PAGE_SIZE, "%x\n", port);
    158	else
    159		count = snprintf(buf, PAGE_SIZE, "disabled\n");
    160
    161	return count;
    162}
    163
    164static ssize_t master_attr_store(struct device *dev,
    165				 struct device_attribute *attr,
    166				 const char *buf, size_t count)
    167{
    168	struct master_attribute *ma =
    169		container_of(attr, struct master_attribute, attr);
    170	struct gth_device *gth = ma->gth;
    171	int old_port, port;
    172
    173	if (kstrtoint(buf, 10, &port) < 0)
    174		return -EINVAL;
    175
    176	if (port >= TH_POSSIBLE_OUTPUTS || port < -1)
    177		return -EINVAL;
    178
    179	spin_lock(&gth->gth_lock);
    180
    181	/* disconnect from the previous output port, if any */
    182	old_port = gth->master[ma->master];
    183	if (old_port >= 0) {
    184		gth->master[ma->master] = -1;
    185		clear_bit(ma->master, gth->output[old_port].master);
    186
    187		/*
    188		 * if the port is active, program this setting,
    189		 * implies that runtime PM is on
    190		 */
    191		if (gth->output[old_port].output->active)
    192			gth_master_set(gth, ma->master, -1);
    193	}
    194
    195	/* connect to the new output port, if any */
    196	if (port >= 0) {
    197		/* check if there's a driver for this port */
    198		if (!gth->output[port].output) {
    199			count = -ENODEV;
    200			goto unlock;
    201		}
    202
    203		set_bit(ma->master, gth->output[port].master);
    204
    205		/* if the port is active, program this setting, see above */
    206		if (gth->output[port].output->active)
    207			gth_master_set(gth, ma->master, port);
    208	}
    209
    210	gth->master[ma->master] = port;
    211
    212unlock:
    213	spin_unlock(&gth->gth_lock);
    214
    215	return count;
    216}
    217
    218struct output_attribute {
    219	struct device_attribute attr;
    220	struct gth_device	*gth;
    221	unsigned int		port;
    222	unsigned int		parm;
    223};
    224
    225#define OUTPUT_PARM(_name, _mask, _r, _w, _what)			\
    226	[TH_OUTPUT_PARM(_name)] = { .name = __stringify(_name),		\
    227				    .get = gth_ ## _what ## _get,	\
    228				    .set = gth_ ## _what ## _set,	\
    229				    .mask = (_mask),			\
    230				    .readable = (_r),			\
    231				    .writable = (_w) }
    232
    233static const struct output_parm {
    234	const char	*name;
    235	unsigned int	(*get)(struct gth_device *gth, int port);
    236	void		(*set)(struct gth_device *gth, int port,
    237			       unsigned int val);
    238	unsigned int	mask;
    239	unsigned int	readable : 1,
    240			writable : 1;
    241} output_parms[] = {
    242	OUTPUT_PARM(port,	0x7,	1, 0, output),
    243	OUTPUT_PARM(null,	BIT(3),	1, 1, output),
    244	OUTPUT_PARM(drop,	BIT(4),	1, 1, output),
    245	OUTPUT_PARM(reset,	BIT(5),	1, 0, output),
    246	OUTPUT_PARM(flush,	BIT(7),	0, 1, output),
    247	OUTPUT_PARM(smcfreq,	0xffff,	1, 1, smcfreq),
    248};
    249
    250static void
    251gth_output_parm_set(struct gth_device *gth, int port, unsigned int parm,
    252		    unsigned int val)
    253{
    254	unsigned int config = output_parms[parm].get(gth, port);
    255	unsigned int mask = output_parms[parm].mask;
    256	unsigned int shift = __ffs(mask);
    257
    258	config &= ~mask;
    259	config |= (val << shift) & mask;
    260	output_parms[parm].set(gth, port, config);
    261}
    262
    263static unsigned int
    264gth_output_parm_get(struct gth_device *gth, int port, unsigned int parm)
    265{
    266	unsigned int config = output_parms[parm].get(gth, port);
    267	unsigned int mask = output_parms[parm].mask;
    268	unsigned int shift = __ffs(mask);
    269
    270	config &= mask;
    271	config >>= shift;
    272	return config;
    273}
    274
    275/*
    276 * Reset outputs and sources
    277 */
    278static int intel_th_gth_reset(struct gth_device *gth)
    279{
    280	u32 reg;
    281	int port, i;
    282
    283	reg = ioread32(gth->base + REG_GTH_SCRPD0);
    284	if (reg & SCRPD_DEBUGGER_IN_USE)
    285		return -EBUSY;
    286
    287	/* Always save/restore STH and TU registers in S0ix entry/exit */
    288	reg |= SCRPD_STH_IS_ENABLED | SCRPD_TRIGGER_IS_ENABLED;
    289	iowrite32(reg, gth->base + REG_GTH_SCRPD0);
    290
    291	/* output ports */
    292	for (port = 0; port < 8; port++) {
    293		if (gth_output_parm_get(gth, port, TH_OUTPUT_PARM(port)) ==
    294		    GTH_NONE)
    295			continue;
    296
    297		gth_output_set(gth, port, 0);
    298		gth_smcfreq_set(gth, port, 16);
    299	}
    300	/* disable overrides */
    301	iowrite32(0, gth->base + REG_GTH_DESTOVR);
    302
    303	/* masters swdest_0~31 and gswdest */
    304	for (i = 0; i < 33; i++)
    305		iowrite32(0, gth->base + REG_GTH_SWDEST0 + i * 4);
    306
    307	/* sources */
    308	iowrite32(0, gth->base + REG_GTH_SCR);
    309	iowrite32(0xfc, gth->base + REG_GTH_SCR2);
    310
    311	/* setup CTS for single trigger */
    312	iowrite32(CTS_EVENT_ENABLE_IF_ANYTHING, gth->base + REG_CTS_C0S0_EN);
    313	iowrite32(CTS_ACTION_CONTROL_SET_STATE(CTS_STATE_IDLE) |
    314		  CTS_ACTION_CONTROL_TRIGGER, gth->base + REG_CTS_C0S0_ACT);
    315
    316	return 0;
    317}
    318
    319/*
    320 * "outputs" attribute group
    321 */
    322
    323static ssize_t output_attr_show(struct device *dev,
    324				struct device_attribute *attr,
    325				char *buf)
    326{
    327	struct output_attribute *oa =
    328		container_of(attr, struct output_attribute, attr);
    329	struct gth_device *gth = oa->gth;
    330	size_t count;
    331
    332	pm_runtime_get_sync(dev);
    333
    334	spin_lock(&gth->gth_lock);
    335	count = snprintf(buf, PAGE_SIZE, "%x\n",
    336			 gth_output_parm_get(gth, oa->port, oa->parm));
    337	spin_unlock(&gth->gth_lock);
    338
    339	pm_runtime_put(dev);
    340
    341	return count;
    342}
    343
    344static ssize_t output_attr_store(struct device *dev,
    345				 struct device_attribute *attr,
    346				 const char *buf, size_t count)
    347{
    348	struct output_attribute *oa =
    349		container_of(attr, struct output_attribute, attr);
    350	struct gth_device *gth = oa->gth;
    351	unsigned int config;
    352
    353	if (kstrtouint(buf, 16, &config) < 0)
    354		return -EINVAL;
    355
    356	pm_runtime_get_sync(dev);
    357
    358	spin_lock(&gth->gth_lock);
    359	gth_output_parm_set(gth, oa->port, oa->parm, config);
    360	spin_unlock(&gth->gth_lock);
    361
    362	pm_runtime_put(dev);
    363
    364	return count;
    365}
    366
    367static int intel_th_master_attributes(struct gth_device *gth)
    368{
    369	struct master_attribute *master_attrs;
    370	struct attribute **attrs;
    371	int i, nattrs = TH_CONFIGURABLE_MASTERS + 2;
    372
    373	attrs = devm_kcalloc(gth->dev, nattrs, sizeof(void *), GFP_KERNEL);
    374	if (!attrs)
    375		return -ENOMEM;
    376
    377	master_attrs = devm_kcalloc(gth->dev, nattrs,
    378				    sizeof(struct master_attribute),
    379				    GFP_KERNEL);
    380	if (!master_attrs)
    381		return -ENOMEM;
    382
    383	for (i = 0; i < TH_CONFIGURABLE_MASTERS + 1; i++) {
    384		char *name;
    385
    386		name = devm_kasprintf(gth->dev, GFP_KERNEL, "%d%s", i,
    387				      i == TH_CONFIGURABLE_MASTERS ? "+" : "");
    388		if (!name)
    389			return -ENOMEM;
    390
    391		master_attrs[i].attr.attr.name = name;
    392		master_attrs[i].attr.attr.mode = S_IRUGO | S_IWUSR;
    393		master_attrs[i].attr.show = master_attr_show;
    394		master_attrs[i].attr.store = master_attr_store;
    395
    396		sysfs_attr_init(&master_attrs[i].attr.attr);
    397		attrs[i] = &master_attrs[i].attr.attr;
    398
    399		master_attrs[i].gth = gth;
    400		master_attrs[i].master = i;
    401	}
    402
    403	gth->master_group.name	= "masters";
    404	gth->master_group.attrs = attrs;
    405
    406	return sysfs_create_group(&gth->dev->kobj, &gth->master_group);
    407}
    408
    409static int intel_th_output_attributes(struct gth_device *gth)
    410{
    411	struct output_attribute *out_attrs;
    412	struct attribute **attrs;
    413	int i, j, nouts = TH_POSSIBLE_OUTPUTS;
    414	int nparms = ARRAY_SIZE(output_parms);
    415	int nattrs = nouts * nparms + 1;
    416
    417	attrs = devm_kcalloc(gth->dev, nattrs, sizeof(void *), GFP_KERNEL);
    418	if (!attrs)
    419		return -ENOMEM;
    420
    421	out_attrs = devm_kcalloc(gth->dev, nattrs,
    422				 sizeof(struct output_attribute),
    423				 GFP_KERNEL);
    424	if (!out_attrs)
    425		return -ENOMEM;
    426
    427	for (i = 0; i < nouts; i++) {
    428		for (j = 0; j < nparms; j++) {
    429			unsigned int idx = i * nparms + j;
    430			char *name;
    431
    432			name = devm_kasprintf(gth->dev, GFP_KERNEL, "%d_%s", i,
    433					      output_parms[j].name);
    434			if (!name)
    435				return -ENOMEM;
    436
    437			out_attrs[idx].attr.attr.name = name;
    438
    439			if (output_parms[j].readable) {
    440				out_attrs[idx].attr.attr.mode |= S_IRUGO;
    441				out_attrs[idx].attr.show = output_attr_show;
    442			}
    443
    444			if (output_parms[j].writable) {
    445				out_attrs[idx].attr.attr.mode |= S_IWUSR;
    446				out_attrs[idx].attr.store = output_attr_store;
    447			}
    448
    449			sysfs_attr_init(&out_attrs[idx].attr.attr);
    450			attrs[idx] = &out_attrs[idx].attr.attr;
    451
    452			out_attrs[idx].gth = gth;
    453			out_attrs[idx].port = i;
    454			out_attrs[idx].parm = j;
    455		}
    456	}
    457
    458	gth->output_group.name	= "outputs";
    459	gth->output_group.attrs = attrs;
    460
    461	return sysfs_create_group(&gth->dev->kobj, &gth->output_group);
    462}
    463
    464/**
    465 * intel_th_gth_stop() - stop tracing to an output device
    466 * @gth:		GTH device
    467 * @output:		output device's descriptor
    468 * @capture_done:	set when no more traces will be captured
    469 *
    470 * This will stop tracing using force storeEn off signal and wait for the
    471 * pipelines to be empty for the corresponding output port.
    472 */
    473static void intel_th_gth_stop(struct gth_device *gth,
    474			      struct intel_th_output *output,
    475			      bool capture_done)
    476{
    477	struct intel_th_device *outdev =
    478		container_of(output, struct intel_th_device, output);
    479	struct intel_th_driver *outdrv =
    480		to_intel_th_driver(outdev->dev.driver);
    481	unsigned long count;
    482	u32 reg;
    483	u32 scr2 = 0xfc | (capture_done ? 1 : 0);
    484
    485	iowrite32(0, gth->base + REG_GTH_SCR);
    486	iowrite32(scr2, gth->base + REG_GTH_SCR2);
    487
    488	/* wait on pipeline empty for the given port */
    489	for (reg = 0, count = GTH_PLE_WAITLOOP_DEPTH;
    490	     count && !(reg & BIT(output->port)); count--) {
    491		reg = ioread32(gth->base + REG_GTH_STAT);
    492		cpu_relax();
    493	}
    494
    495	if (!count)
    496		dev_dbg(gth->dev, "timeout waiting for GTH[%d] PLE\n",
    497			output->port);
    498
    499	/* wait on output piepline empty */
    500	if (outdrv->wait_empty)
    501		outdrv->wait_empty(outdev);
    502
    503	/* clear force capture done for next captures */
    504	iowrite32(0xfc, gth->base + REG_GTH_SCR2);
    505}
    506
    507/**
    508 * intel_th_gth_start() - start tracing to an output device
    509 * @gth:	GTH device
    510 * @output:	output device's descriptor
    511 *
    512 * This will start tracing using force storeEn signal.
    513 */
    514static void intel_th_gth_start(struct gth_device *gth,
    515			       struct intel_th_output *output)
    516{
    517	u32 scr = 0xfc0000;
    518
    519	if (output->multiblock)
    520		scr |= 0xff;
    521
    522	iowrite32(scr, gth->base + REG_GTH_SCR);
    523	iowrite32(0, gth->base + REG_GTH_SCR2);
    524}
    525
    526/**
    527 * intel_th_gth_disable() - disable tracing to an output device
    528 * @thdev:	GTH device
    529 * @output:	output device's descriptor
    530 *
    531 * This will deconfigure all masters set to output to this device,
    532 * disable tracing using force storeEn off signal and wait for the
    533 * "pipeline empty" bit for corresponding output port.
    534 */
    535static void intel_th_gth_disable(struct intel_th_device *thdev,
    536				 struct intel_th_output *output)
    537{
    538	struct gth_device *gth = dev_get_drvdata(&thdev->dev);
    539	int master;
    540	u32 reg;
    541
    542	spin_lock(&gth->gth_lock);
    543	output->active = false;
    544
    545	for_each_set_bit(master, gth->output[output->port].master,
    546			 TH_CONFIGURABLE_MASTERS + 1) {
    547		gth_master_set(gth, master, -1);
    548	}
    549	spin_unlock(&gth->gth_lock);
    550
    551	intel_th_gth_stop(gth, output, true);
    552
    553	reg = ioread32(gth->base + REG_GTH_SCRPD0);
    554	reg &= ~output->scratchpad;
    555	iowrite32(reg, gth->base + REG_GTH_SCRPD0);
    556}
    557
    558static void gth_tscu_resync(struct gth_device *gth)
    559{
    560	u32 reg;
    561
    562	reg = ioread32(gth->base + REG_TSCU_TSUCTRL);
    563	reg &= ~TSUCTRL_CTCRESYNC;
    564	iowrite32(reg, gth->base + REG_TSCU_TSUCTRL);
    565}
    566
    567static void intel_th_gth_prepare(struct intel_th_device *thdev,
    568				 struct intel_th_output *output)
    569{
    570	struct gth_device *gth = dev_get_drvdata(&thdev->dev);
    571	int count;
    572
    573	/*
    574	 * Wait until the output port is in reset before we start
    575	 * programming it.
    576	 */
    577	for (count = GTH_PLE_WAITLOOP_DEPTH;
    578	     count && !(gth_output_get(gth, output->port) & BIT(5)); count--)
    579		cpu_relax();
    580}
    581
    582/**
    583 * intel_th_gth_enable() - enable tracing to an output device
    584 * @thdev:	GTH device
    585 * @output:	output device's descriptor
    586 *
    587 * This will configure all masters set to output to this device and
    588 * enable tracing using force storeEn signal.
    589 */
    590static void intel_th_gth_enable(struct intel_th_device *thdev,
    591				struct intel_th_output *output)
    592{
    593	struct gth_device *gth = dev_get_drvdata(&thdev->dev);
    594	struct intel_th *th = to_intel_th(thdev);
    595	int master;
    596	u32 scrpd;
    597
    598	spin_lock(&gth->gth_lock);
    599	for_each_set_bit(master, gth->output[output->port].master,
    600			 TH_CONFIGURABLE_MASTERS + 1) {
    601		gth_master_set(gth, master, output->port);
    602	}
    603
    604	output->active = true;
    605	spin_unlock(&gth->gth_lock);
    606
    607	if (INTEL_TH_CAP(th, tscu_enable))
    608		gth_tscu_resync(gth);
    609
    610	scrpd = ioread32(gth->base + REG_GTH_SCRPD0);
    611	scrpd |= output->scratchpad;
    612	iowrite32(scrpd, gth->base + REG_GTH_SCRPD0);
    613
    614	intel_th_gth_start(gth, output);
    615}
    616
    617/**
    618 * intel_th_gth_switch() - execute a switch sequence
    619 * @thdev:	GTH device
    620 * @output:	output device's descriptor
    621 *
    622 * This will execute a switch sequence that will trigger a switch window
    623 * when tracing to MSC in multi-block mode.
    624 */
    625static void intel_th_gth_switch(struct intel_th_device *thdev,
    626				struct intel_th_output *output)
    627{
    628	struct gth_device *gth = dev_get_drvdata(&thdev->dev);
    629	unsigned long count;
    630	u32 reg;
    631
    632	/* trigger */
    633	iowrite32(0, gth->base + REG_CTS_CTL);
    634	iowrite32(CTS_CTL_SEQUENCER_ENABLE, gth->base + REG_CTS_CTL);
    635	/* wait on trigger status */
    636	for (reg = 0, count = CTS_TRIG_WAITLOOP_DEPTH;
    637	     count && !(reg & BIT(4)); count--) {
    638		reg = ioread32(gth->base + REG_CTS_STAT);
    639		cpu_relax();
    640	}
    641	if (!count)
    642		dev_dbg(&thdev->dev, "timeout waiting for CTS Trigger\n");
    643
    644	/* De-assert the trigger */
    645	iowrite32(0, gth->base + REG_CTS_CTL);
    646
    647	intel_th_gth_stop(gth, output, false);
    648	intel_th_gth_start(gth, output);
    649}
    650
    651/**
    652 * intel_th_gth_assign() - assign output device to a GTH output port
    653 * @thdev:	GTH device
    654 * @othdev:	output device
    655 *
    656 * This will match a given output device parameters against present
    657 * output ports on the GTH and fill out relevant bits in output device's
    658 * descriptor.
    659 *
    660 * Return:	0 on success, -errno on error.
    661 */
    662static int intel_th_gth_assign(struct intel_th_device *thdev,
    663			       struct intel_th_device *othdev)
    664{
    665	struct gth_device *gth = dev_get_drvdata(&thdev->dev);
    666	int i, id;
    667
    668	if (thdev->host_mode)
    669		return -EBUSY;
    670
    671	if (othdev->type != INTEL_TH_OUTPUT)
    672		return -EINVAL;
    673
    674	for (i = 0, id = 0; i < TH_POSSIBLE_OUTPUTS; i++) {
    675		if (gth->output[i].port_type != othdev->output.type)
    676			continue;
    677
    678		if (othdev->id == -1 || othdev->id == id)
    679			goto found;
    680
    681		id++;
    682	}
    683
    684	return -ENOENT;
    685
    686found:
    687	spin_lock(&gth->gth_lock);
    688	othdev->output.port = i;
    689	othdev->output.active = false;
    690	gth->output[i].output = &othdev->output;
    691	spin_unlock(&gth->gth_lock);
    692
    693	return 0;
    694}
    695
    696/**
    697 * intel_th_gth_unassign() - deassociate an output device from its output port
    698 * @thdev:	GTH device
    699 * @othdev:	output device
    700 */
    701static void intel_th_gth_unassign(struct intel_th_device *thdev,
    702				  struct intel_th_device *othdev)
    703{
    704	struct gth_device *gth = dev_get_drvdata(&thdev->dev);
    705	int port = othdev->output.port;
    706	int master;
    707
    708	if (thdev->host_mode)
    709		return;
    710
    711	spin_lock(&gth->gth_lock);
    712	othdev->output.port = -1;
    713	othdev->output.active = false;
    714	gth->output[port].output = NULL;
    715	for (master = 0; master < TH_CONFIGURABLE_MASTERS + 1; master++)
    716		if (gth->master[master] == port)
    717			gth->master[master] = -1;
    718	spin_unlock(&gth->gth_lock);
    719}
    720
    721static int
    722intel_th_gth_set_output(struct intel_th_device *thdev, unsigned int master)
    723{
    724	struct gth_device *gth = dev_get_drvdata(&thdev->dev);
    725	int port = 0; /* FIXME: make default output configurable */
    726
    727	/*
    728	 * everything above TH_CONFIGURABLE_MASTERS is controlled by the
    729	 * same register
    730	 */
    731	if (master > TH_CONFIGURABLE_MASTERS)
    732		master = TH_CONFIGURABLE_MASTERS;
    733
    734	spin_lock(&gth->gth_lock);
    735	if (gth->master[master] == -1) {
    736		set_bit(master, gth->output[port].master);
    737		gth->master[master] = port;
    738	}
    739	spin_unlock(&gth->gth_lock);
    740
    741	return 0;
    742}
    743
    744static int intel_th_gth_probe(struct intel_th_device *thdev)
    745{
    746	struct device *dev = &thdev->dev;
    747	struct intel_th *th = dev_get_drvdata(dev->parent);
    748	struct gth_device *gth;
    749	struct resource *res;
    750	void __iomem *base;
    751	int i, ret;
    752
    753	res = intel_th_device_get_resource(thdev, IORESOURCE_MEM, 0);
    754	if (!res)
    755		return -ENODEV;
    756
    757	base = devm_ioremap(dev, res->start, resource_size(res));
    758	if (!base)
    759		return -ENOMEM;
    760
    761	gth = devm_kzalloc(dev, sizeof(*gth), GFP_KERNEL);
    762	if (!gth)
    763		return -ENOMEM;
    764
    765	gth->dev = dev;
    766	gth->base = base;
    767	spin_lock_init(&gth->gth_lock);
    768
    769	dev_set_drvdata(dev, gth);
    770
    771	/*
    772	 * Host mode can be signalled via SW means or via SCRPD_DEBUGGER_IN_USE
    773	 * bit. Either way, don't reset HW in this case, and don't export any
    774	 * capture configuration attributes. Also, refuse to assign output
    775	 * drivers to ports, see intel_th_gth_assign().
    776	 */
    777	if (thdev->host_mode)
    778		return 0;
    779
    780	ret = intel_th_gth_reset(gth);
    781	if (ret) {
    782		if (ret != -EBUSY)
    783			return ret;
    784
    785		thdev->host_mode = true;
    786
    787		return 0;
    788	}
    789
    790	for (i = 0; i < TH_CONFIGURABLE_MASTERS + 1; i++)
    791		gth->master[i] = -1;
    792
    793	for (i = 0; i < TH_POSSIBLE_OUTPUTS; i++) {
    794		gth->output[i].gth = gth;
    795		gth->output[i].index = i;
    796		gth->output[i].port_type =
    797			gth_output_parm_get(gth, i, TH_OUTPUT_PARM(port));
    798		if (gth->output[i].port_type == GTH_NONE)
    799			continue;
    800
    801		ret = intel_th_output_enable(th, gth->output[i].port_type);
    802		/* -ENODEV is ok, we just won't have that device enumerated */
    803		if (ret && ret != -ENODEV)
    804			return ret;
    805	}
    806
    807	if (intel_th_output_attributes(gth) ||
    808	    intel_th_master_attributes(gth)) {
    809		pr_warn("Can't initialize sysfs attributes\n");
    810
    811		if (gth->output_group.attrs)
    812			sysfs_remove_group(&gth->dev->kobj, &gth->output_group);
    813		return -ENOMEM;
    814	}
    815
    816	return 0;
    817}
    818
    819static void intel_th_gth_remove(struct intel_th_device *thdev)
    820{
    821	struct gth_device *gth = dev_get_drvdata(&thdev->dev);
    822
    823	sysfs_remove_group(&gth->dev->kobj, &gth->output_group);
    824	sysfs_remove_group(&gth->dev->kobj, &gth->master_group);
    825}
    826
    827static struct intel_th_driver intel_th_gth_driver = {
    828	.probe		= intel_th_gth_probe,
    829	.remove		= intel_th_gth_remove,
    830	.assign		= intel_th_gth_assign,
    831	.unassign	= intel_th_gth_unassign,
    832	.set_output	= intel_th_gth_set_output,
    833	.prepare	= intel_th_gth_prepare,
    834	.enable		= intel_th_gth_enable,
    835	.trig_switch	= intel_th_gth_switch,
    836	.disable	= intel_th_gth_disable,
    837	.driver	= {
    838		.name	= "gth",
    839		.owner	= THIS_MODULE,
    840	},
    841};
    842
    843module_driver(intel_th_gth_driver,
    844	      intel_th_driver_register,
    845	      intel_th_driver_unregister);
    846
    847MODULE_ALIAS("intel_th_switch");
    848MODULE_LICENSE("GPL v2");
    849MODULE_DESCRIPTION("Intel(R) Trace Hub Global Trace Hub driver");
    850MODULE_AUTHOR("Alexander Shishkin <alexander.shishkin@linux.intel.com>");