xref: /openbmc/linux/drivers/gpu/drm/amd/amdgpu/tonga_ih.c (revision adb19164)
1 /*
2  * Copyright 2014 Advanced Micro Devices, Inc.
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice shall be included in
12  * all copies or substantial portions of the Software.
13  *
14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
17  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20  * OTHER DEALINGS IN THE SOFTWARE.
21  *
22  */
23 
24 #include <linux/pci.h>
25 
26 #include "amdgpu.h"
27 #include "amdgpu_ih.h"
28 #include "vid.h"
29 
30 #include "oss/oss_3_0_d.h"
31 #include "oss/oss_3_0_sh_mask.h"
32 
33 #include "bif/bif_5_1_d.h"
34 #include "bif/bif_5_1_sh_mask.h"
35 
36 /*
37  * Interrupts
38  * Starting with r6xx, interrupts are handled via a ring buffer.
39  * Ring buffers are areas of GPU accessible memory that the GPU
40  * writes interrupt vectors into and the host reads vectors out of.
41  * There is a rptr (read pointer) that determines where the
42  * host is currently reading, and a wptr (write pointer)
43  * which determines where the GPU has written.  When the
44  * pointers are equal, the ring is idle.  When the GPU
45  * writes vectors to the ring buffer, it increments the
46  * wptr.  When there is an interrupt, the host then starts
47  * fetching commands and processing them until the pointers are
48  * equal again at which point it updates the rptr.
49  */
50 
51 static void tonga_ih_set_interrupt_funcs(struct amdgpu_device *adev);
52 
53 /**
54  * tonga_ih_enable_interrupts - Enable the interrupt ring buffer
55  *
56  * @adev: amdgpu_device pointer
57  *
58  * Enable the interrupt ring buffer (VI).
59  */
60 static void tonga_ih_enable_interrupts(struct amdgpu_device *adev)
61 {
62 	u32 ih_rb_cntl = RREG32(mmIH_RB_CNTL);
63 
64 	ih_rb_cntl = REG_SET_FIELD(ih_rb_cntl, IH_RB_CNTL, RB_ENABLE, 1);
65 	ih_rb_cntl = REG_SET_FIELD(ih_rb_cntl, IH_RB_CNTL, ENABLE_INTR, 1);
66 	WREG32(mmIH_RB_CNTL, ih_rb_cntl);
67 	adev->irq.ih.enabled = true;
68 }
69 
70 /**
71  * tonga_ih_disable_interrupts - Disable the interrupt ring buffer
72  *
73  * @adev: amdgpu_device pointer
74  *
75  * Disable the interrupt ring buffer (VI).
76  */
77 static void tonga_ih_disable_interrupts(struct amdgpu_device *adev)
78 {
79 	u32 ih_rb_cntl = RREG32(mmIH_RB_CNTL);
80 
81 	ih_rb_cntl = REG_SET_FIELD(ih_rb_cntl, IH_RB_CNTL, RB_ENABLE, 0);
82 	ih_rb_cntl = REG_SET_FIELD(ih_rb_cntl, IH_RB_CNTL, ENABLE_INTR, 0);
83 	WREG32(mmIH_RB_CNTL, ih_rb_cntl);
84 	/* set rptr, wptr to 0 */
85 	WREG32(mmIH_RB_RPTR, 0);
86 	WREG32(mmIH_RB_WPTR, 0);
87 	adev->irq.ih.enabled = false;
88 	adev->irq.ih.rptr = 0;
89 }
90 
91 /**
92  * tonga_ih_irq_init - init and enable the interrupt ring
93  *
94  * @adev: amdgpu_device pointer
95  *
96  * Allocate a ring buffer for the interrupt controller,
97  * enable the RLC, disable interrupts, enable the IH
98  * ring buffer and enable it (VI).
99  * Called at device load and reume.
100  * Returns 0 for success, errors for failure.
101  */
102 static int tonga_ih_irq_init(struct amdgpu_device *adev)
103 {
104 	u32 interrupt_cntl, ih_rb_cntl, ih_doorbell_rtpr;
105 	struct amdgpu_ih_ring *ih = &adev->irq.ih;
106 	int rb_bufsz;
107 
108 	/* disable irqs */
109 	tonga_ih_disable_interrupts(adev);
110 
111 	/* setup interrupt control */
112 	WREG32(mmINTERRUPT_CNTL2, adev->dummy_page_addr >> 8);
113 	interrupt_cntl = RREG32(mmINTERRUPT_CNTL);
114 	/* INTERRUPT_CNTL__IH_DUMMY_RD_OVERRIDE_MASK=0 - dummy read disabled with msi, enabled without msi
115 	 * INTERRUPT_CNTL__IH_DUMMY_RD_OVERRIDE_MASK=1 - dummy read controlled by IH_DUMMY_RD_EN
116 	 */
117 	interrupt_cntl = REG_SET_FIELD(interrupt_cntl, INTERRUPT_CNTL, IH_DUMMY_RD_OVERRIDE, 0);
118 	/* INTERRUPT_CNTL__IH_REQ_NONSNOOP_EN_MASK=1 if ring is in non-cacheable memory, e.g., vram */
119 	interrupt_cntl = REG_SET_FIELD(interrupt_cntl, INTERRUPT_CNTL, IH_REQ_NONSNOOP_EN, 0);
120 	WREG32(mmINTERRUPT_CNTL, interrupt_cntl);
121 
122 	/* Ring Buffer base. [39:8] of 40-bit address of the beginning of the ring buffer*/
123 	WREG32(mmIH_RB_BASE, ih->gpu_addr >> 8);
124 
125 	rb_bufsz = order_base_2(adev->irq.ih.ring_size / 4);
126 	ih_rb_cntl = REG_SET_FIELD(0, IH_RB_CNTL, WPTR_OVERFLOW_CLEAR, 1);
127 	ih_rb_cntl = REG_SET_FIELD(ih_rb_cntl, IH_RB_CNTL, RB_SIZE, rb_bufsz);
128 	/* Ring Buffer write pointer writeback. If enabled, IH_RB_WPTR register value is written to memory */
129 	ih_rb_cntl = REG_SET_FIELD(ih_rb_cntl, IH_RB_CNTL, WPTR_WRITEBACK_ENABLE, 1);
130 	ih_rb_cntl = REG_SET_FIELD(ih_rb_cntl, IH_RB_CNTL, MC_VMID, 0);
131 
132 	if (adev->irq.msi_enabled)
133 		ih_rb_cntl = REG_SET_FIELD(ih_rb_cntl, IH_RB_CNTL, RPTR_REARM, 1);
134 
135 	WREG32(mmIH_RB_CNTL, ih_rb_cntl);
136 
137 	/* set the writeback address whether it's enabled or not */
138 	WREG32(mmIH_RB_WPTR_ADDR_LO, lower_32_bits(ih->wptr_addr));
139 	WREG32(mmIH_RB_WPTR_ADDR_HI, upper_32_bits(ih->wptr_addr) & 0xFF);
140 
141 	/* set rptr, wptr to 0 */
142 	WREG32(mmIH_RB_RPTR, 0);
143 	WREG32(mmIH_RB_WPTR, 0);
144 
145 	ih_doorbell_rtpr = RREG32(mmIH_DOORBELL_RPTR);
146 	if (adev->irq.ih.use_doorbell) {
147 		ih_doorbell_rtpr = REG_SET_FIELD(ih_doorbell_rtpr, IH_DOORBELL_RPTR,
148 						 OFFSET, adev->irq.ih.doorbell_index);
149 		ih_doorbell_rtpr = REG_SET_FIELD(ih_doorbell_rtpr, IH_DOORBELL_RPTR,
150 						 ENABLE, 1);
151 	} else {
152 		ih_doorbell_rtpr = REG_SET_FIELD(ih_doorbell_rtpr, IH_DOORBELL_RPTR,
153 						 ENABLE, 0);
154 	}
155 	WREG32(mmIH_DOORBELL_RPTR, ih_doorbell_rtpr);
156 
157 	pci_set_master(adev->pdev);
158 
159 	/* enable interrupts */
160 	tonga_ih_enable_interrupts(adev);
161 
162 	return 0;
163 }
164 
165 /**
166  * tonga_ih_irq_disable - disable interrupts
167  *
168  * @adev: amdgpu_device pointer
169  *
170  * Disable interrupts on the hw (VI).
171  */
172 static void tonga_ih_irq_disable(struct amdgpu_device *adev)
173 {
174 	tonga_ih_disable_interrupts(adev);
175 
176 	/* Wait and acknowledge irq */
177 	mdelay(1);
178 }
179 
180 /**
181  * tonga_ih_get_wptr - get the IH ring buffer wptr
182  *
183  * @adev: amdgpu_device pointer
184  * @ih: IH ring buffer to fetch wptr
185  *
186  * Get the IH ring buffer wptr from either the register
187  * or the writeback memory buffer (VI).  Also check for
188  * ring buffer overflow and deal with it.
189  * Used by cz_irq_process(VI).
190  * Returns the value of the wptr.
191  */
192 static u32 tonga_ih_get_wptr(struct amdgpu_device *adev,
193 			     struct amdgpu_ih_ring *ih)
194 {
195 	u32 wptr, tmp;
196 
197 	wptr = le32_to_cpu(*ih->wptr_cpu);
198 
199 	if (!REG_GET_FIELD(wptr, IH_RB_WPTR, RB_OVERFLOW))
200 		goto out;
201 
202 	/* Double check that the overflow wasn't already cleared. */
203 	wptr = RREG32(mmIH_RB_WPTR);
204 
205 	if (!REG_GET_FIELD(wptr, IH_RB_WPTR, RB_OVERFLOW))
206 		goto out;
207 
208 	wptr = REG_SET_FIELD(wptr, IH_RB_WPTR, RB_OVERFLOW, 0);
209 
210 	/* When a ring buffer overflow happen start parsing interrupt
211 	 * from the last not overwritten vector (wptr + 16). Hopefully
212 	 * this should allow us to catchup.
213 	 */
214 
215 	dev_warn(adev->dev, "IH ring buffer overflow (0x%08X, 0x%08X, 0x%08X)\n",
216 		wptr, ih->rptr, (wptr + 16) & ih->ptr_mask);
217 	ih->rptr = (wptr + 16) & ih->ptr_mask;
218 	tmp = RREG32(mmIH_RB_CNTL);
219 	tmp = REG_SET_FIELD(tmp, IH_RB_CNTL, WPTR_OVERFLOW_CLEAR, 1);
220 	WREG32(mmIH_RB_CNTL, tmp);
221 
222 	/* Unset the CLEAR_OVERFLOW bit immediately so new overflows
223 	 * can be detected.
224 	 */
225 	tmp = REG_SET_FIELD(tmp, IH_RB_CNTL, WPTR_OVERFLOW_CLEAR, 0);
226 	WREG32(mmIH_RB_CNTL, tmp);
227 
228 out:
229 	return (wptr & ih->ptr_mask);
230 }
231 
232 /**
233  * tonga_ih_decode_iv - decode an interrupt vector
234  *
235  * @adev: amdgpu_device pointer
236  * @ih: IH ring buffer to decode
237  * @entry: IV entry to place decoded information into
238  *
239  * Decodes the interrupt vector at the current rptr
240  * position and also advance the position.
241  */
242 static void tonga_ih_decode_iv(struct amdgpu_device *adev,
243 			       struct amdgpu_ih_ring *ih,
244 			       struct amdgpu_iv_entry *entry)
245 {
246 	/* wptr/rptr are in bytes! */
247 	u32 ring_index = ih->rptr >> 2;
248 	uint32_t dw[4];
249 
250 	dw[0] = le32_to_cpu(ih->ring[ring_index + 0]);
251 	dw[1] = le32_to_cpu(ih->ring[ring_index + 1]);
252 	dw[2] = le32_to_cpu(ih->ring[ring_index + 2]);
253 	dw[3] = le32_to_cpu(ih->ring[ring_index + 3]);
254 
255 	entry->client_id = AMDGPU_IRQ_CLIENTID_LEGACY;
256 	entry->src_id = dw[0] & 0xff;
257 	entry->src_data[0] = dw[1] & 0xfffffff;
258 	entry->ring_id = dw[2] & 0xff;
259 	entry->vmid = (dw[2] >> 8) & 0xff;
260 	entry->pasid = (dw[2] >> 16) & 0xffff;
261 
262 	/* wptr/rptr are in bytes! */
263 	ih->rptr += 16;
264 }
265 
266 /**
267  * tonga_ih_set_rptr - set the IH ring buffer rptr
268  *
269  * @adev: amdgpu_device pointer
270  * @ih: IH ring buffer to set rptr
271  *
272  * Set the IH ring buffer rptr.
273  */
274 static void tonga_ih_set_rptr(struct amdgpu_device *adev,
275 			      struct amdgpu_ih_ring *ih)
276 {
277 	if (ih->use_doorbell) {
278 		/* XXX check if swapping is necessary on BE */
279 		*ih->rptr_cpu = ih->rptr;
280 		WDOORBELL32(ih->doorbell_index, ih->rptr);
281 	} else {
282 		WREG32(mmIH_RB_RPTR, ih->rptr);
283 	}
284 }
285 
286 static int tonga_ih_early_init(void *handle)
287 {
288 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
289 	int ret;
290 
291 	ret = amdgpu_irq_add_domain(adev);
292 	if (ret)
293 		return ret;
294 
295 	tonga_ih_set_interrupt_funcs(adev);
296 
297 	return 0;
298 }
299 
300 static int tonga_ih_sw_init(void *handle)
301 {
302 	int r;
303 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
304 
305 	r = amdgpu_ih_ring_init(adev, &adev->irq.ih, 64 * 1024, true);
306 	if (r)
307 		return r;
308 
309 	adev->irq.ih.use_doorbell = true;
310 	adev->irq.ih.doorbell_index = adev->doorbell_index.ih;
311 
312 	r = amdgpu_irq_init(adev);
313 
314 	return r;
315 }
316 
317 static int tonga_ih_sw_fini(void *handle)
318 {
319 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
320 
321 	amdgpu_irq_fini_sw(adev);
322 	amdgpu_irq_remove_domain(adev);
323 
324 	return 0;
325 }
326 
327 static int tonga_ih_hw_init(void *handle)
328 {
329 	int r;
330 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
331 
332 	r = tonga_ih_irq_init(adev);
333 	if (r)
334 		return r;
335 
336 	return 0;
337 }
338 
339 static int tonga_ih_hw_fini(void *handle)
340 {
341 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
342 
343 	tonga_ih_irq_disable(adev);
344 
345 	return 0;
346 }
347 
348 static int tonga_ih_suspend(void *handle)
349 {
350 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
351 
352 	return tonga_ih_hw_fini(adev);
353 }
354 
355 static int tonga_ih_resume(void *handle)
356 {
357 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
358 
359 	return tonga_ih_hw_init(adev);
360 }
361 
362 static bool tonga_ih_is_idle(void *handle)
363 {
364 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
365 	u32 tmp = RREG32(mmSRBM_STATUS);
366 
367 	if (REG_GET_FIELD(tmp, SRBM_STATUS, IH_BUSY))
368 		return false;
369 
370 	return true;
371 }
372 
373 static int tonga_ih_wait_for_idle(void *handle)
374 {
375 	unsigned i;
376 	u32 tmp;
377 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
378 
379 	for (i = 0; i < adev->usec_timeout; i++) {
380 		/* read MC_STATUS */
381 		tmp = RREG32(mmSRBM_STATUS);
382 		if (!REG_GET_FIELD(tmp, SRBM_STATUS, IH_BUSY))
383 			return 0;
384 		udelay(1);
385 	}
386 	return -ETIMEDOUT;
387 }
388 
389 static bool tonga_ih_check_soft_reset(void *handle)
390 {
391 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
392 	u32 srbm_soft_reset = 0;
393 	u32 tmp = RREG32(mmSRBM_STATUS);
394 
395 	if (tmp & SRBM_STATUS__IH_BUSY_MASK)
396 		srbm_soft_reset = REG_SET_FIELD(srbm_soft_reset, SRBM_SOFT_RESET,
397 						SOFT_RESET_IH, 1);
398 
399 	if (srbm_soft_reset) {
400 		adev->irq.srbm_soft_reset = srbm_soft_reset;
401 		return true;
402 	} else {
403 		adev->irq.srbm_soft_reset = 0;
404 		return false;
405 	}
406 }
407 
408 static int tonga_ih_pre_soft_reset(void *handle)
409 {
410 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
411 
412 	if (!adev->irq.srbm_soft_reset)
413 		return 0;
414 
415 	return tonga_ih_hw_fini(adev);
416 }
417 
418 static int tonga_ih_post_soft_reset(void *handle)
419 {
420 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
421 
422 	if (!adev->irq.srbm_soft_reset)
423 		return 0;
424 
425 	return tonga_ih_hw_init(adev);
426 }
427 
428 static int tonga_ih_soft_reset(void *handle)
429 {
430 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
431 	u32 srbm_soft_reset;
432 
433 	if (!adev->irq.srbm_soft_reset)
434 		return 0;
435 	srbm_soft_reset = adev->irq.srbm_soft_reset;
436 
437 	if (srbm_soft_reset) {
438 		u32 tmp;
439 
440 		tmp = RREG32(mmSRBM_SOFT_RESET);
441 		tmp |= srbm_soft_reset;
442 		dev_info(adev->dev, "SRBM_SOFT_RESET=0x%08X\n", tmp);
443 		WREG32(mmSRBM_SOFT_RESET, tmp);
444 		tmp = RREG32(mmSRBM_SOFT_RESET);
445 
446 		udelay(50);
447 
448 		tmp &= ~srbm_soft_reset;
449 		WREG32(mmSRBM_SOFT_RESET, tmp);
450 		tmp = RREG32(mmSRBM_SOFT_RESET);
451 
452 		/* Wait a little for things to settle down */
453 		udelay(50);
454 	}
455 
456 	return 0;
457 }
458 
459 static int tonga_ih_set_clockgating_state(void *handle,
460 					  enum amd_clockgating_state state)
461 {
462 	return 0;
463 }
464 
465 static int tonga_ih_set_powergating_state(void *handle,
466 					  enum amd_powergating_state state)
467 {
468 	return 0;
469 }
470 
471 static const struct amd_ip_funcs tonga_ih_ip_funcs = {
472 	.name = "tonga_ih",
473 	.early_init = tonga_ih_early_init,
474 	.late_init = NULL,
475 	.sw_init = tonga_ih_sw_init,
476 	.sw_fini = tonga_ih_sw_fini,
477 	.hw_init = tonga_ih_hw_init,
478 	.hw_fini = tonga_ih_hw_fini,
479 	.suspend = tonga_ih_suspend,
480 	.resume = tonga_ih_resume,
481 	.is_idle = tonga_ih_is_idle,
482 	.wait_for_idle = tonga_ih_wait_for_idle,
483 	.check_soft_reset = tonga_ih_check_soft_reset,
484 	.pre_soft_reset = tonga_ih_pre_soft_reset,
485 	.soft_reset = tonga_ih_soft_reset,
486 	.post_soft_reset = tonga_ih_post_soft_reset,
487 	.set_clockgating_state = tonga_ih_set_clockgating_state,
488 	.set_powergating_state = tonga_ih_set_powergating_state,
489 };
490 
491 static const struct amdgpu_ih_funcs tonga_ih_funcs = {
492 	.get_wptr = tonga_ih_get_wptr,
493 	.decode_iv = tonga_ih_decode_iv,
494 	.set_rptr = tonga_ih_set_rptr
495 };
496 
497 static void tonga_ih_set_interrupt_funcs(struct amdgpu_device *adev)
498 {
499 	adev->irq.ih_funcs = &tonga_ih_funcs;
500 }
501 
502 const struct amdgpu_ip_block_version tonga_ih_ip_block = {
503 	.type = AMD_IP_BLOCK_TYPE_IH,
504 	.major = 3,
505 	.minor = 0,
506 	.rev = 0,
507 	.funcs = &tonga_ih_ip_funcs,
508 };
509