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 
19 #define ADF_VINTSOU_OFFSET	0x204
20 #define ADF_VINTMSK_OFFSET	0x208
21 #define ADF_VINTSOU_BUN		BIT(0)
22 #define ADF_VINTSOU_PF2VF	BIT(1)
23 
24 static struct workqueue_struct *adf_vf_stop_wq;
25 
26 struct adf_vf_stop_data {
27 	struct adf_accel_dev *accel_dev;
28 	struct work_struct work;
29 };
30 
adf_enable_pf2vf_interrupts(struct adf_accel_dev * accel_dev)31 void adf_enable_pf2vf_interrupts(struct adf_accel_dev *accel_dev)
32 {
33 	void __iomem *pmisc_addr = adf_get_pmisc_base(accel_dev);
34 
35 	ADF_CSR_WR(pmisc_addr, ADF_VINTMSK_OFFSET, 0x0);
36 }
37 
adf_disable_pf2vf_interrupts(struct adf_accel_dev * accel_dev)38 void adf_disable_pf2vf_interrupts(struct adf_accel_dev *accel_dev)
39 {
40 	void __iomem *pmisc_addr = adf_get_pmisc_base(accel_dev);
41 
42 	ADF_CSR_WR(pmisc_addr, ADF_VINTMSK_OFFSET, 0x2);
43 }
44 EXPORT_SYMBOL_GPL(adf_disable_pf2vf_interrupts);
45 
adf_enable_msi(struct adf_accel_dev * accel_dev)46 static int adf_enable_msi(struct adf_accel_dev *accel_dev)
47 {
48 	struct adf_accel_pci *pci_dev_info = &accel_dev->accel_pci_dev;
49 	int stat = pci_alloc_irq_vectors(pci_dev_info->pci_dev, 1, 1,
50 					 PCI_IRQ_MSI);
51 	if (unlikely(stat < 0)) {
52 		dev_err(&GET_DEV(accel_dev),
53 			"Failed to enable MSI interrupt: %d\n", stat);
54 		return stat;
55 	}
56 
57 	return 0;
58 }
59 
adf_disable_msi(struct adf_accel_dev * accel_dev)60 static void adf_disable_msi(struct adf_accel_dev *accel_dev)
61 {
62 	struct pci_dev *pdev = accel_to_pci_dev(accel_dev);
63 
64 	pci_free_irq_vectors(pdev);
65 }
66 
adf_dev_stop_async(struct work_struct * work)67 static void adf_dev_stop_async(struct work_struct *work)
68 {
69 	struct adf_vf_stop_data *stop_data =
70 		container_of(work, struct adf_vf_stop_data, work);
71 	struct adf_accel_dev *accel_dev = stop_data->accel_dev;
72 
73 	adf_dev_restarting_notify(accel_dev);
74 	adf_dev_stop(accel_dev);
75 	adf_dev_shutdown(accel_dev);
76 
77 	/* Re-enable PF2VF interrupts */
78 	adf_enable_pf2vf_interrupts(accel_dev);
79 	kfree(stop_data);
80 }
81 
adf_pf2vf_handle_pf_restarting(struct adf_accel_dev * accel_dev)82 int adf_pf2vf_handle_pf_restarting(struct adf_accel_dev *accel_dev)
83 {
84 	struct adf_vf_stop_data *stop_data;
85 
86 	clear_bit(ADF_STATUS_PF_RUNNING, &accel_dev->status);
87 	stop_data = kzalloc(sizeof(*stop_data), GFP_ATOMIC);
88 	if (!stop_data) {
89 		dev_err(&GET_DEV(accel_dev),
90 			"Couldn't schedule stop for vf_%d\n",
91 			accel_dev->accel_id);
92 		return -ENOMEM;
93 	}
94 	stop_data->accel_dev = accel_dev;
95 	INIT_WORK(&stop_data->work, adf_dev_stop_async);
96 	queue_work(adf_vf_stop_wq, &stop_data->work);
97 
98 	return 0;
99 }
100 
adf_pf2vf_bh_handler(void * data)101 static void adf_pf2vf_bh_handler(void *data)
102 {
103 	struct adf_accel_dev *accel_dev = data;
104 	bool ret;
105 
106 	ret = adf_recv_and_handle_pf2vf_msg(accel_dev);
107 	if (ret)
108 		/* Re-enable PF2VF interrupts */
109 		adf_enable_pf2vf_interrupts(accel_dev);
110 
111 	return;
112 
113 }
114 
adf_setup_pf2vf_bh(struct adf_accel_dev * accel_dev)115 static int adf_setup_pf2vf_bh(struct adf_accel_dev *accel_dev)
116 {
117 	tasklet_init(&accel_dev->vf.pf2vf_bh_tasklet,
118 		     (void *)adf_pf2vf_bh_handler, (unsigned long)accel_dev);
119 
120 	mutex_init(&accel_dev->vf.vf2pf_lock);
121 	return 0;
122 }
123 
adf_cleanup_pf2vf_bh(struct adf_accel_dev * accel_dev)124 static void adf_cleanup_pf2vf_bh(struct adf_accel_dev *accel_dev)
125 {
126 	tasklet_disable(&accel_dev->vf.pf2vf_bh_tasklet);
127 	tasklet_kill(&accel_dev->vf.pf2vf_bh_tasklet);
128 	mutex_destroy(&accel_dev->vf.vf2pf_lock);
129 }
130 
adf_isr(int irq,void * privdata)131 static irqreturn_t adf_isr(int irq, void *privdata)
132 {
133 	struct adf_accel_dev *accel_dev = privdata;
134 	struct adf_hw_device_data *hw_data = accel_dev->hw_device;
135 	struct adf_hw_csr_ops *csr_ops = &hw_data->csr_ops;
136 	struct adf_bar *pmisc =
137 			&GET_BARS(accel_dev)[hw_data->get_misc_bar_id(hw_data)];
138 	void __iomem *pmisc_bar_addr = pmisc->virt_addr;
139 	bool handled = false;
140 	u32 v_int, v_mask;
141 
142 	/* Read VF INT source CSR to determine the source of VF interrupt */
143 	v_int = ADF_CSR_RD(pmisc_bar_addr, ADF_VINTSOU_OFFSET);
144 
145 	/* Read VF INT mask CSR to determine which sources are masked */
146 	v_mask = ADF_CSR_RD(pmisc_bar_addr, ADF_VINTMSK_OFFSET);
147 
148 	/*
149 	 * Recompute v_int ignoring sources that are masked. This is to
150 	 * avoid rescheduling the tasklet for interrupts already handled
151 	 */
152 	v_int &= ~v_mask;
153 
154 	/* Check for PF2VF interrupt */
155 	if (v_int & ADF_VINTSOU_PF2VF) {
156 		/* Disable PF to VF interrupt */
157 		adf_disable_pf2vf_interrupts(accel_dev);
158 
159 		/* Schedule tasklet to handle interrupt BH */
160 		tasklet_hi_schedule(&accel_dev->vf.pf2vf_bh_tasklet);
161 		handled = true;
162 	}
163 
164 	/* Check bundle interrupt */
165 	if (v_int & ADF_VINTSOU_BUN) {
166 		struct adf_etr_data *etr_data = accel_dev->transport;
167 		struct adf_etr_bank_data *bank = &etr_data->banks[0];
168 
169 		/* Disable Flag and Coalesce Ring Interrupts */
170 		csr_ops->write_csr_int_flag_and_col(bank->csr_addr,
171 						    bank->bank_number, 0);
172 		tasklet_hi_schedule(&bank->resp_handler);
173 		handled = true;
174 	}
175 
176 	return handled ? IRQ_HANDLED : IRQ_NONE;
177 }
178 
adf_request_msi_irq(struct adf_accel_dev * accel_dev)179 static int adf_request_msi_irq(struct adf_accel_dev *accel_dev)
180 {
181 	struct pci_dev *pdev = accel_to_pci_dev(accel_dev);
182 	unsigned int cpu;
183 	int ret;
184 
185 	snprintf(accel_dev->vf.irq_name, ADF_MAX_MSIX_VECTOR_NAME,
186 		 "qat_%02x:%02d.%02d", pdev->bus->number, PCI_SLOT(pdev->devfn),
187 		 PCI_FUNC(pdev->devfn));
188 	ret = request_irq(pdev->irq, adf_isr, 0, accel_dev->vf.irq_name,
189 			  (void *)accel_dev);
190 	if (ret) {
191 		dev_err(&GET_DEV(accel_dev), "failed to enable irq for %s\n",
192 			accel_dev->vf.irq_name);
193 		return ret;
194 	}
195 	cpu = accel_dev->accel_id % num_online_cpus();
196 	irq_set_affinity_hint(pdev->irq, get_cpu_mask(cpu));
197 	accel_dev->vf.irq_enabled = true;
198 
199 	return ret;
200 }
201 
adf_setup_bh(struct adf_accel_dev * accel_dev)202 static int adf_setup_bh(struct adf_accel_dev *accel_dev)
203 {
204 	struct adf_etr_data *priv_data = accel_dev->transport;
205 
206 	tasklet_init(&priv_data->banks[0].resp_handler, adf_response_handler,
207 		     (unsigned long)priv_data->banks);
208 	return 0;
209 }
210 
adf_cleanup_bh(struct adf_accel_dev * accel_dev)211 static void adf_cleanup_bh(struct adf_accel_dev *accel_dev)
212 {
213 	struct adf_etr_data *priv_data = accel_dev->transport;
214 
215 	tasklet_disable(&priv_data->banks[0].resp_handler);
216 	tasklet_kill(&priv_data->banks[0].resp_handler);
217 }
218 
219 /**
220  * adf_vf_isr_resource_free() - Free IRQ for acceleration device
221  * @accel_dev:  Pointer to acceleration device.
222  *
223  * Function frees interrupts for acceleration device virtual function.
224  */
adf_vf_isr_resource_free(struct adf_accel_dev * accel_dev)225 void adf_vf_isr_resource_free(struct adf_accel_dev *accel_dev)
226 {
227 	struct pci_dev *pdev = accel_to_pci_dev(accel_dev);
228 
229 	if (accel_dev->vf.irq_enabled) {
230 		irq_set_affinity_hint(pdev->irq, NULL);
231 		free_irq(pdev->irq, accel_dev);
232 	}
233 	adf_cleanup_bh(accel_dev);
234 	adf_cleanup_pf2vf_bh(accel_dev);
235 	adf_disable_msi(accel_dev);
236 }
237 EXPORT_SYMBOL_GPL(adf_vf_isr_resource_free);
238 
239 /**
240  * adf_vf_isr_resource_alloc() - Allocate IRQ for acceleration device
241  * @accel_dev:  Pointer to acceleration device.
242  *
243  * Function allocates interrupts for acceleration device virtual function.
244  *
245  * Return: 0 on success, error code otherwise.
246  */
adf_vf_isr_resource_alloc(struct adf_accel_dev * accel_dev)247 int adf_vf_isr_resource_alloc(struct adf_accel_dev *accel_dev)
248 {
249 	if (adf_enable_msi(accel_dev))
250 		goto err_out;
251 
252 	if (adf_setup_pf2vf_bh(accel_dev))
253 		goto err_disable_msi;
254 
255 	if (adf_setup_bh(accel_dev))
256 		goto err_cleanup_pf2vf_bh;
257 
258 	if (adf_request_msi_irq(accel_dev))
259 		goto err_cleanup_bh;
260 
261 	return 0;
262 
263 err_cleanup_bh:
264 	adf_cleanup_bh(accel_dev);
265 
266 err_cleanup_pf2vf_bh:
267 	adf_cleanup_pf2vf_bh(accel_dev);
268 
269 err_disable_msi:
270 	adf_disable_msi(accel_dev);
271 
272 err_out:
273 	return -EFAULT;
274 }
275 EXPORT_SYMBOL_GPL(adf_vf_isr_resource_alloc);
276 
277 /**
278  * adf_flush_vf_wq() - Flush workqueue for VF
279  * @accel_dev:  Pointer to acceleration device.
280  *
281  * Function disables the PF/VF interrupts on the VF so that no new messages
282  * are received and flushes the workqueue 'adf_vf_stop_wq'.
283  *
284  * Return: void.
285  */
adf_flush_vf_wq(struct adf_accel_dev * accel_dev)286 void adf_flush_vf_wq(struct adf_accel_dev *accel_dev)
287 {
288 	adf_disable_pf2vf_interrupts(accel_dev);
289 
290 	flush_workqueue(adf_vf_stop_wq);
291 }
292 EXPORT_SYMBOL_GPL(adf_flush_vf_wq);
293 
294 /**
295  * adf_init_vf_wq() - Init workqueue for VF
296  *
297  * Function init workqueue 'adf_vf_stop_wq' for VF.
298  *
299  * Return: 0 on success, error code otherwise.
300  */
adf_init_vf_wq(void)301 int __init adf_init_vf_wq(void)
302 {
303 	adf_vf_stop_wq = alloc_workqueue("adf_vf_stop_wq", WQ_MEM_RECLAIM, 0);
304 
305 	return !adf_vf_stop_wq ? -EFAULT : 0;
306 }
307 
adf_exit_vf_wq(void)308 void adf_exit_vf_wq(void)
309 {
310 	if (adf_vf_stop_wq)
311 		destroy_workqueue(adf_vf_stop_wq);
312 
313 	adf_vf_stop_wq = NULL;
314 }
315