1 // SPDX-License-Identifier: (BSD-3-Clause OR GPL-2.0-only)
2 /* Copyright(c) 2014 - 2020 Intel Corporation */
3 #include <linux/kernel.h>
4 #include <linux/init.h>
5 #include <linux/types.h>
6 #include <linux/pci.h>
7 #include <linux/slab.h>
8 #include <linux/errno.h>
9 #include <linux/interrupt.h>
10 #include <linux/workqueue.h>
11 #include "adf_accel_devices.h"
12 #include "adf_common_drv.h"
13 #include "adf_cfg.h"
14 #include "adf_cfg_strings.h"
15 #include "adf_cfg_common.h"
16 #include "adf_transport_access_macros.h"
17 #include "adf_transport_internal.h"
18 #include "adf_pf2vf_msg.h"
19 
20 #define ADF_VINTSOU_OFFSET	0x204
21 #define ADF_VINTMSK_OFFSET	0x208
22 #define ADF_VINTSOU_BUN		BIT(0)
23 #define ADF_VINTSOU_PF2VF	BIT(1)
24 
25 static struct workqueue_struct *adf_vf_stop_wq;
26 
27 struct adf_vf_stop_data {
28 	struct adf_accel_dev *accel_dev;
29 	struct work_struct work;
30 };
31 
adf_enable_pf2vf_interrupts(struct adf_accel_dev * accel_dev)32 void adf_enable_pf2vf_interrupts(struct adf_accel_dev *accel_dev)
33 {
34 	struct adf_accel_pci *pci_info = &accel_dev->accel_pci_dev;
35 	struct adf_hw_device_data *hw_data = accel_dev->hw_device;
36 	void __iomem *pmisc_bar_addr =
37 		pci_info->pci_bars[hw_data->get_misc_bar_id(hw_data)].virt_addr;
38 
39 	ADF_CSR_WR(pmisc_bar_addr, ADF_VINTMSK_OFFSET, 0x0);
40 }
41 
adf_disable_pf2vf_interrupts(struct adf_accel_dev * accel_dev)42 void adf_disable_pf2vf_interrupts(struct adf_accel_dev *accel_dev)
43 {
44 	struct adf_accel_pci *pci_info = &accel_dev->accel_pci_dev;
45 	struct adf_hw_device_data *hw_data = accel_dev->hw_device;
46 	void __iomem *pmisc_bar_addr =
47 		pci_info->pci_bars[hw_data->get_misc_bar_id(hw_data)].virt_addr;
48 
49 	ADF_CSR_WR(pmisc_bar_addr, ADF_VINTMSK_OFFSET, 0x2);
50 }
51 EXPORT_SYMBOL_GPL(adf_disable_pf2vf_interrupts);
52 
adf_enable_msi(struct adf_accel_dev * accel_dev)53 static int adf_enable_msi(struct adf_accel_dev *accel_dev)
54 {
55 	struct adf_accel_pci *pci_dev_info = &accel_dev->accel_pci_dev;
56 	int stat = pci_alloc_irq_vectors(pci_dev_info->pci_dev, 1, 1,
57 					 PCI_IRQ_MSI);
58 	if (unlikely(stat < 0)) {
59 		dev_err(&GET_DEV(accel_dev),
60 			"Failed to enable MSI interrupt: %d\n", stat);
61 		return stat;
62 	}
63 
64 	return 0;
65 }
66 
adf_disable_msi(struct adf_accel_dev * accel_dev)67 static void adf_disable_msi(struct adf_accel_dev *accel_dev)
68 {
69 	struct pci_dev *pdev = accel_to_pci_dev(accel_dev);
70 
71 	pci_free_irq_vectors(pdev);
72 }
73 
adf_dev_stop_async(struct work_struct * work)74 static void adf_dev_stop_async(struct work_struct *work)
75 {
76 	struct adf_vf_stop_data *stop_data =
77 		container_of(work, struct adf_vf_stop_data, work);
78 	struct adf_accel_dev *accel_dev = stop_data->accel_dev;
79 
80 	adf_dev_stop(accel_dev);
81 	adf_dev_shutdown(accel_dev);
82 
83 	/* Re-enable PF2VF interrupts */
84 	adf_enable_pf2vf_interrupts(accel_dev);
85 	kfree(stop_data);
86 }
87 
adf_pf2vf_bh_handler(void * data)88 static void adf_pf2vf_bh_handler(void *data)
89 {
90 	struct adf_accel_dev *accel_dev = data;
91 	struct adf_hw_device_data *hw_data = accel_dev->hw_device;
92 	struct adf_bar *pmisc =
93 			&GET_BARS(accel_dev)[hw_data->get_misc_bar_id(hw_data)];
94 	void __iomem *pmisc_bar_addr = pmisc->virt_addr;
95 	u32 msg;
96 
97 	/* Read the message from PF */
98 	msg = ADF_CSR_RD(pmisc_bar_addr, hw_data->get_pf2vf_offset(0));
99 	if (!(msg & ADF_PF2VF_INT)) {
100 		dev_info(&GET_DEV(accel_dev),
101 			 "Spurious PF2VF interrupt, msg %X. Ignored\n", msg);
102 		goto out;
103 	}
104 
105 	if (!(msg & ADF_PF2VF_MSGORIGIN_SYSTEM))
106 		/* Ignore legacy non-system (non-kernel) PF2VF messages */
107 		goto err;
108 
109 	switch ((msg & ADF_PF2VF_MSGTYPE_MASK) >> ADF_PF2VF_MSGTYPE_SHIFT) {
110 	case ADF_PF2VF_MSGTYPE_RESTARTING: {
111 		struct adf_vf_stop_data *stop_data;
112 
113 		dev_dbg(&GET_DEV(accel_dev),
114 			"Restarting msg received from PF 0x%x\n", msg);
115 
116 		clear_bit(ADF_STATUS_PF_RUNNING, &accel_dev->status);
117 
118 		stop_data = kzalloc(sizeof(*stop_data), GFP_ATOMIC);
119 		if (!stop_data) {
120 			dev_err(&GET_DEV(accel_dev),
121 				"Couldn't schedule stop for vf_%d\n",
122 				accel_dev->accel_id);
123 			return;
124 		}
125 		stop_data->accel_dev = accel_dev;
126 		INIT_WORK(&stop_data->work, adf_dev_stop_async);
127 		queue_work(adf_vf_stop_wq, &stop_data->work);
128 		/* To ack, clear the PF2VFINT bit */
129 		msg &= ~ADF_PF2VF_INT;
130 		ADF_CSR_WR(pmisc_bar_addr, hw_data->get_pf2vf_offset(0), msg);
131 		return;
132 	}
133 	case ADF_PF2VF_MSGTYPE_VERSION_RESP:
134 		dev_dbg(&GET_DEV(accel_dev),
135 			"Version resp received from PF 0x%x\n", msg);
136 		accel_dev->vf.pf_version =
137 			(msg & ADF_PF2VF_VERSION_RESP_VERS_MASK) >>
138 			ADF_PF2VF_VERSION_RESP_VERS_SHIFT;
139 		accel_dev->vf.compatible =
140 			(msg & ADF_PF2VF_VERSION_RESP_RESULT_MASK) >>
141 			ADF_PF2VF_VERSION_RESP_RESULT_SHIFT;
142 		complete(&accel_dev->vf.iov_msg_completion);
143 		break;
144 	default:
145 		goto err;
146 	}
147 
148 	/* To ack, clear the PF2VFINT bit */
149 	msg &= ~ADF_PF2VF_INT;
150 	ADF_CSR_WR(pmisc_bar_addr, hw_data->get_pf2vf_offset(0), msg);
151 
152 out:
153 	/* Re-enable PF2VF interrupts */
154 	adf_enable_pf2vf_interrupts(accel_dev);
155 	return;
156 err:
157 	dev_err(&GET_DEV(accel_dev),
158 		"Unknown message from PF (0x%x); leaving PF2VF ints disabled\n",
159 		msg);
160 }
161 
adf_setup_pf2vf_bh(struct adf_accel_dev * accel_dev)162 static int adf_setup_pf2vf_bh(struct adf_accel_dev *accel_dev)
163 {
164 	tasklet_init(&accel_dev->vf.pf2vf_bh_tasklet,
165 		     (void *)adf_pf2vf_bh_handler, (unsigned long)accel_dev);
166 
167 	mutex_init(&accel_dev->vf.vf2pf_lock);
168 	return 0;
169 }
170 
adf_cleanup_pf2vf_bh(struct adf_accel_dev * accel_dev)171 static void adf_cleanup_pf2vf_bh(struct adf_accel_dev *accel_dev)
172 {
173 	tasklet_disable(&accel_dev->vf.pf2vf_bh_tasklet);
174 	tasklet_kill(&accel_dev->vf.pf2vf_bh_tasklet);
175 	mutex_destroy(&accel_dev->vf.vf2pf_lock);
176 }
177 
adf_isr(int irq,void * privdata)178 static irqreturn_t adf_isr(int irq, void *privdata)
179 {
180 	struct adf_accel_dev *accel_dev = privdata;
181 	struct adf_hw_device_data *hw_data = accel_dev->hw_device;
182 	struct adf_hw_csr_ops *csr_ops = &hw_data->csr_ops;
183 	struct adf_bar *pmisc =
184 			&GET_BARS(accel_dev)[hw_data->get_misc_bar_id(hw_data)];
185 	void __iomem *pmisc_bar_addr = pmisc->virt_addr;
186 	bool handled = false;
187 	u32 v_int, v_mask;
188 
189 	/* Read VF INT source CSR to determine the source of VF interrupt */
190 	v_int = ADF_CSR_RD(pmisc_bar_addr, ADF_VINTSOU_OFFSET);
191 
192 	/* Read VF INT mask CSR to determine which sources are masked */
193 	v_mask = ADF_CSR_RD(pmisc_bar_addr, ADF_VINTMSK_OFFSET);
194 
195 	/*
196 	 * Recompute v_int ignoring sources that are masked. This is to
197 	 * avoid rescheduling the tasklet for interrupts already handled
198 	 */
199 	v_int &= ~v_mask;
200 
201 	/* Check for PF2VF interrupt */
202 	if (v_int & ADF_VINTSOU_PF2VF) {
203 		/* Disable PF to VF interrupt */
204 		adf_disable_pf2vf_interrupts(accel_dev);
205 
206 		/* Schedule tasklet to handle interrupt BH */
207 		tasklet_hi_schedule(&accel_dev->vf.pf2vf_bh_tasklet);
208 		handled = true;
209 	}
210 
211 	/* Check bundle interrupt */
212 	if (v_int & ADF_VINTSOU_BUN) {
213 		struct adf_etr_data *etr_data = accel_dev->transport;
214 		struct adf_etr_bank_data *bank = &etr_data->banks[0];
215 
216 		/* Disable Flag and Coalesce Ring Interrupts */
217 		csr_ops->write_csr_int_flag_and_col(bank->csr_addr,
218 						    bank->bank_number, 0);
219 		tasklet_hi_schedule(&bank->resp_handler);
220 		handled = true;
221 	}
222 
223 	return handled ? IRQ_HANDLED : IRQ_NONE;
224 }
225 
adf_request_msi_irq(struct adf_accel_dev * accel_dev)226 static int adf_request_msi_irq(struct adf_accel_dev *accel_dev)
227 {
228 	struct pci_dev *pdev = accel_to_pci_dev(accel_dev);
229 	unsigned int cpu;
230 	int ret;
231 
232 	snprintf(accel_dev->vf.irq_name, ADF_MAX_MSIX_VECTOR_NAME,
233 		 "qat_%02x:%02d.%02d", pdev->bus->number, PCI_SLOT(pdev->devfn),
234 		 PCI_FUNC(pdev->devfn));
235 	ret = request_irq(pdev->irq, adf_isr, 0, accel_dev->vf.irq_name,
236 			  (void *)accel_dev);
237 	if (ret) {
238 		dev_err(&GET_DEV(accel_dev), "failed to enable irq for %s\n",
239 			accel_dev->vf.irq_name);
240 		return ret;
241 	}
242 	cpu = accel_dev->accel_id % num_online_cpus();
243 	irq_set_affinity_hint(pdev->irq, get_cpu_mask(cpu));
244 	accel_dev->vf.irq_enabled = true;
245 
246 	return ret;
247 }
248 
adf_setup_bh(struct adf_accel_dev * accel_dev)249 static int adf_setup_bh(struct adf_accel_dev *accel_dev)
250 {
251 	struct adf_etr_data *priv_data = accel_dev->transport;
252 
253 	tasklet_init(&priv_data->banks[0].resp_handler, adf_response_handler,
254 		     (unsigned long)priv_data->banks);
255 	return 0;
256 }
257 
adf_cleanup_bh(struct adf_accel_dev * accel_dev)258 static void adf_cleanup_bh(struct adf_accel_dev *accel_dev)
259 {
260 	struct adf_etr_data *priv_data = accel_dev->transport;
261 
262 	tasklet_disable(&priv_data->banks[0].resp_handler);
263 	tasklet_kill(&priv_data->banks[0].resp_handler);
264 }
265 
266 /**
267  * adf_vf_isr_resource_free() - Free IRQ for acceleration device
268  * @accel_dev:  Pointer to acceleration device.
269  *
270  * Function frees interrupts for acceleration device virtual function.
271  */
adf_vf_isr_resource_free(struct adf_accel_dev * accel_dev)272 void adf_vf_isr_resource_free(struct adf_accel_dev *accel_dev)
273 {
274 	struct pci_dev *pdev = accel_to_pci_dev(accel_dev);
275 
276 	if (accel_dev->vf.irq_enabled) {
277 		irq_set_affinity_hint(pdev->irq, NULL);
278 		free_irq(pdev->irq, accel_dev);
279 	}
280 	adf_cleanup_bh(accel_dev);
281 	adf_cleanup_pf2vf_bh(accel_dev);
282 	adf_disable_msi(accel_dev);
283 }
284 EXPORT_SYMBOL_GPL(adf_vf_isr_resource_free);
285 
286 /**
287  * adf_vf_isr_resource_alloc() - Allocate IRQ for acceleration device
288  * @accel_dev:  Pointer to acceleration device.
289  *
290  * Function allocates interrupts for acceleration device virtual function.
291  *
292  * Return: 0 on success, error code otherwise.
293  */
adf_vf_isr_resource_alloc(struct adf_accel_dev * accel_dev)294 int adf_vf_isr_resource_alloc(struct adf_accel_dev *accel_dev)
295 {
296 	if (adf_enable_msi(accel_dev))
297 		goto err_out;
298 
299 	if (adf_setup_pf2vf_bh(accel_dev))
300 		goto err_disable_msi;
301 
302 	if (adf_setup_bh(accel_dev))
303 		goto err_cleanup_pf2vf_bh;
304 
305 	if (adf_request_msi_irq(accel_dev))
306 		goto err_cleanup_bh;
307 
308 	return 0;
309 
310 err_cleanup_bh:
311 	adf_cleanup_bh(accel_dev);
312 
313 err_cleanup_pf2vf_bh:
314 	adf_cleanup_pf2vf_bh(accel_dev);
315 
316 err_disable_msi:
317 	adf_disable_msi(accel_dev);
318 
319 err_out:
320 	return -EFAULT;
321 }
322 EXPORT_SYMBOL_GPL(adf_vf_isr_resource_alloc);
323 
324 /**
325  * adf_flush_vf_wq() - Flush workqueue for VF
326  * @accel_dev:  Pointer to acceleration device.
327  *
328  * Function disables the PF/VF interrupts on the VF so that no new messages
329  * are received and flushes the workqueue 'adf_vf_stop_wq'.
330  *
331  * Return: void.
332  */
adf_flush_vf_wq(struct adf_accel_dev * accel_dev)333 void adf_flush_vf_wq(struct adf_accel_dev *accel_dev)
334 {
335 	adf_disable_pf2vf_interrupts(accel_dev);
336 
337 	flush_workqueue(adf_vf_stop_wq);
338 }
339 EXPORT_SYMBOL_GPL(adf_flush_vf_wq);
340 
341 /**
342  * adf_init_vf_wq() - Init workqueue for VF
343  *
344  * Function init workqueue 'adf_vf_stop_wq' for VF.
345  *
346  * Return: 0 on success, error code otherwise.
347  */
adf_init_vf_wq(void)348 int __init adf_init_vf_wq(void)
349 {
350 	adf_vf_stop_wq = alloc_workqueue("adf_vf_stop_wq", WQ_MEM_RECLAIM, 0);
351 
352 	return !adf_vf_stop_wq ? -EFAULT : 0;
353 }
354 
adf_exit_vf_wq(void)355 void adf_exit_vf_wq(void)
356 {
357 	if (adf_vf_stop_wq)
358 		destroy_workqueue(adf_vf_stop_wq);
359 
360 	adf_vf_stop_wq = NULL;
361 }
362