xref: /linux/arch/powerpc/platforms/powernv/opal-imc.c (revision bd628c1bed7902ec1f24ba0fe70758949146abbe)
1 /*
2  * OPAL IMC interface detection driver
3  * Supported on POWERNV platform
4  *
5  * Copyright	(C) 2017 Madhavan Srinivasan, IBM Corporation.
6  *		(C) 2017 Anju T Sudhakar, IBM Corporation.
7  *		(C) 2017 Hemant K Shaw, IBM Corporation.
8  *
9  * This program is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU General Public License
11  * as published by the Free Software Foundation; either version
12  * 2 of the License, or later version.
13  */
14 #include <linux/kernel.h>
15 #include <linux/platform_device.h>
16 #include <linux/of.h>
17 #include <linux/of_address.h>
18 #include <linux/of_platform.h>
19 #include <linux/crash_dump.h>
20 #include <asm/opal.h>
21 #include <asm/io.h>
22 #include <asm/imc-pmu.h>
23 #include <asm/cputhreads.h>
24 #include <asm/debugfs.h>
25 
26 static struct dentry *imc_debugfs_parent;
27 
28 /* Helpers to export imc command and mode via debugfs */
29 static int imc_mem_get(void *data, u64 *val)
30 {
31 	*val = cpu_to_be64(*(u64 *)data);
32 	return 0;
33 }
34 
35 static int imc_mem_set(void *data, u64 val)
36 {
37 	*(u64 *)data = cpu_to_be64(val);
38 	return 0;
39 }
40 DEFINE_DEBUGFS_ATTRIBUTE(fops_imc_x64, imc_mem_get, imc_mem_set, "0x%016llx\n");
41 
42 static struct dentry *imc_debugfs_create_x64(const char *name, umode_t mode,
43 					     struct dentry *parent, u64  *value)
44 {
45 	return debugfs_create_file_unsafe(name, mode, parent,
46 					  value, &fops_imc_x64);
47 }
48 
49 /*
50  * export_imc_mode_and_cmd: Create a debugfs interface
51  *                     for imc_cmd and imc_mode
52  *                     for each node in the system.
53  *  imc_mode and imc_cmd can be changed by echo into
54  *  this interface.
55  */
56 static void export_imc_mode_and_cmd(struct device_node *node,
57 				    struct imc_pmu *pmu_ptr)
58 {
59 	static u64 loc, *imc_mode_addr, *imc_cmd_addr;
60 	int chip = 0, nid;
61 	char mode[16], cmd[16];
62 	u32 cb_offset;
63 
64 	imc_debugfs_parent = debugfs_create_dir("imc", powerpc_debugfs_root);
65 
66 	/*
67 	 * Return here, either because 'imc' directory already exists,
68 	 * Or failed to create a new one.
69 	 */
70 	if (!imc_debugfs_parent)
71 		return;
72 
73 	if (of_property_read_u32(node, "cb_offset", &cb_offset))
74 		cb_offset = IMC_CNTL_BLK_OFFSET;
75 
76 	for_each_node(nid) {
77 		loc = (u64)(pmu_ptr->mem_info[chip].vbase) + cb_offset;
78 		imc_mode_addr = (u64 *)(loc + IMC_CNTL_BLK_MODE_OFFSET);
79 		sprintf(mode, "imc_mode_%d", nid);
80 		if (!imc_debugfs_create_x64(mode, 0600, imc_debugfs_parent,
81 					    imc_mode_addr))
82 			goto err;
83 
84 		imc_cmd_addr = (u64 *)(loc + IMC_CNTL_BLK_CMD_OFFSET);
85 		sprintf(cmd, "imc_cmd_%d", nid);
86 		if (!imc_debugfs_create_x64(cmd, 0600, imc_debugfs_parent,
87 					    imc_cmd_addr))
88 			goto err;
89 		chip++;
90 	}
91 	return;
92 
93 err:
94 	debugfs_remove_recursive(imc_debugfs_parent);
95 }
96 
97 /*
98  * imc_get_mem_addr_nest: Function to get nest counter memory region
99  * for each chip
100  */
101 static int imc_get_mem_addr_nest(struct device_node *node,
102 				 struct imc_pmu *pmu_ptr,
103 				 u32 offset)
104 {
105 	int nr_chips = 0, i;
106 	u64 *base_addr_arr, baddr;
107 	u32 *chipid_arr;
108 
109 	nr_chips = of_property_count_u32_elems(node, "chip-id");
110 	if (nr_chips <= 0)
111 		return -ENODEV;
112 
113 	base_addr_arr = kcalloc(nr_chips, sizeof(*base_addr_arr), GFP_KERNEL);
114 	if (!base_addr_arr)
115 		return -ENOMEM;
116 
117 	chipid_arr = kcalloc(nr_chips, sizeof(*chipid_arr), GFP_KERNEL);
118 	if (!chipid_arr) {
119 		kfree(base_addr_arr);
120 		return -ENOMEM;
121 	}
122 
123 	if (of_property_read_u32_array(node, "chip-id", chipid_arr, nr_chips))
124 		goto error;
125 
126 	if (of_property_read_u64_array(node, "base-addr", base_addr_arr,
127 								nr_chips))
128 		goto error;
129 
130 	pmu_ptr->mem_info = kcalloc(nr_chips, sizeof(*pmu_ptr->mem_info),
131 				    GFP_KERNEL);
132 	if (!pmu_ptr->mem_info)
133 		goto error;
134 
135 	for (i = 0; i < nr_chips; i++) {
136 		pmu_ptr->mem_info[i].id = chipid_arr[i];
137 		baddr = base_addr_arr[i] + offset;
138 		pmu_ptr->mem_info[i].vbase = phys_to_virt(baddr);
139 	}
140 
141 	pmu_ptr->imc_counter_mmaped = true;
142 	export_imc_mode_and_cmd(node, pmu_ptr);
143 	kfree(base_addr_arr);
144 	kfree(chipid_arr);
145 	return 0;
146 
147 error:
148 	kfree(base_addr_arr);
149 	kfree(chipid_arr);
150 	return -1;
151 }
152 
153 /*
154  * imc_pmu_create : Takes the parent device which is the pmu unit, pmu_index
155  *		    and domain as the inputs.
156  * Allocates memory for the struct imc_pmu, sets up its domain, size and offsets
157  */
158 static int imc_pmu_create(struct device_node *parent, int pmu_index, int domain)
159 {
160 	int ret = 0;
161 	struct imc_pmu *pmu_ptr;
162 	u32 offset;
163 
164 	/* memory for pmu */
165 	pmu_ptr = kzalloc(sizeof(*pmu_ptr), GFP_KERNEL);
166 	if (!pmu_ptr)
167 		return -ENOMEM;
168 
169 	/* Set the domain */
170 	pmu_ptr->domain = domain;
171 
172 	ret = of_property_read_u32(parent, "size", &pmu_ptr->counter_mem_size);
173 	if (ret) {
174 		ret = -EINVAL;
175 		goto free_pmu;
176 	}
177 
178 	if (!of_property_read_u32(parent, "offset", &offset)) {
179 		if (imc_get_mem_addr_nest(parent, pmu_ptr, offset)) {
180 			ret = -EINVAL;
181 			goto free_pmu;
182 		}
183 	}
184 
185 	/* Function to register IMC pmu */
186 	ret = init_imc_pmu(parent, pmu_ptr, pmu_index);
187 	if (ret) {
188 		pr_err("IMC PMU %s Register failed\n", pmu_ptr->pmu.name);
189 		kfree(pmu_ptr->pmu.name);
190 		if (pmu_ptr->domain == IMC_DOMAIN_NEST)
191 			kfree(pmu_ptr->mem_info);
192 		kfree(pmu_ptr);
193 		return ret;
194 	}
195 
196 	return 0;
197 
198 free_pmu:
199 	kfree(pmu_ptr);
200 	return ret;
201 }
202 
203 static void disable_nest_pmu_counters(void)
204 {
205 	int nid, cpu;
206 	const struct cpumask *l_cpumask;
207 
208 	get_online_cpus();
209 	for_each_node_with_cpus(nid) {
210 		l_cpumask = cpumask_of_node(nid);
211 		cpu = cpumask_first_and(l_cpumask, cpu_online_mask);
212 		if (cpu >= nr_cpu_ids)
213 			continue;
214 		opal_imc_counters_stop(OPAL_IMC_COUNTERS_NEST,
215 				       get_hard_smp_processor_id(cpu));
216 	}
217 	put_online_cpus();
218 }
219 
220 static void disable_core_pmu_counters(void)
221 {
222 	cpumask_t cores_map;
223 	int cpu, rc;
224 
225 	get_online_cpus();
226 	/* Disable the IMC Core functions */
227 	cores_map = cpu_online_cores_map();
228 	for_each_cpu(cpu, &cores_map) {
229 		rc = opal_imc_counters_stop(OPAL_IMC_COUNTERS_CORE,
230 					    get_hard_smp_processor_id(cpu));
231 		if (rc)
232 			pr_err("%s: Failed to stop Core (cpu = %d)\n",
233 				__FUNCTION__, cpu);
234 	}
235 	put_online_cpus();
236 }
237 
238 int get_max_nest_dev(void)
239 {
240 	struct device_node *node;
241 	u32 pmu_units = 0, type;
242 
243 	for_each_compatible_node(node, NULL, IMC_DTB_UNIT_COMPAT) {
244 		if (of_property_read_u32(node, "type", &type))
245 			continue;
246 
247 		if (type == IMC_TYPE_CHIP)
248 			pmu_units++;
249 	}
250 
251 	return pmu_units;
252 }
253 
254 static int opal_imc_counters_probe(struct platform_device *pdev)
255 {
256 	struct device_node *imc_dev = pdev->dev.of_node;
257 	int pmu_count = 0, domain;
258 	bool core_imc_reg = false, thread_imc_reg = false;
259 	u32 type;
260 
261 	/*
262 	 * Check whether this is kdump kernel. If yes, force the engines to
263 	 * stop and return.
264 	 */
265 	if (is_kdump_kernel()) {
266 		disable_nest_pmu_counters();
267 		disable_core_pmu_counters();
268 		return -ENODEV;
269 	}
270 
271 	for_each_compatible_node(imc_dev, NULL, IMC_DTB_UNIT_COMPAT) {
272 		if (of_property_read_u32(imc_dev, "type", &type)) {
273 			pr_warn("IMC Device without type property\n");
274 			continue;
275 		}
276 
277 		switch (type) {
278 		case IMC_TYPE_CHIP:
279 			domain = IMC_DOMAIN_NEST;
280 			break;
281 		case IMC_TYPE_CORE:
282 			domain =IMC_DOMAIN_CORE;
283 			break;
284 		case IMC_TYPE_THREAD:
285 			domain = IMC_DOMAIN_THREAD;
286 			break;
287 		default:
288 			pr_warn("IMC Unknown Device type \n");
289 			domain = -1;
290 			break;
291 		}
292 
293 		if (!imc_pmu_create(imc_dev, pmu_count, domain)) {
294 			if (domain == IMC_DOMAIN_NEST)
295 				pmu_count++;
296 			if (domain == IMC_DOMAIN_CORE)
297 				core_imc_reg = true;
298 			if (domain == IMC_DOMAIN_THREAD)
299 				thread_imc_reg = true;
300 		}
301 	}
302 
303 	/* If none of the nest units are registered, remove debugfs interface */
304 	if (pmu_count == 0)
305 		debugfs_remove_recursive(imc_debugfs_parent);
306 
307 	/* If core imc is not registered, unregister thread-imc */
308 	if (!core_imc_reg && thread_imc_reg)
309 		unregister_thread_imc();
310 
311 	return 0;
312 }
313 
314 static void opal_imc_counters_shutdown(struct platform_device *pdev)
315 {
316 	/*
317 	 * Function only stops the engines which is bare minimum.
318 	 * TODO: Need to handle proper memory cleanup and pmu
319 	 * unregister.
320 	 */
321 	disable_nest_pmu_counters();
322 	disable_core_pmu_counters();
323 }
324 
325 static const struct of_device_id opal_imc_match[] = {
326 	{ .compatible = IMC_DTB_COMPAT },
327 	{},
328 };
329 
330 static struct platform_driver opal_imc_driver = {
331 	.driver = {
332 		.name = "opal-imc-counters",
333 		.of_match_table = opal_imc_match,
334 	},
335 	.probe = opal_imc_counters_probe,
336 	.shutdown = opal_imc_counters_shutdown,
337 };
338 
339 builtin_platform_driver(opal_imc_driver);
340