xref: /openbmc/linux/drivers/gpu/drm/amd/amdgpu/cz_ih.c (revision cc698db4)
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_1_d.h"
31 #include "oss/oss_3_0_1_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 cz_ih_set_interrupt_funcs(struct amdgpu_device *adev);
52 
53 /**
54  * cz_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 cz_ih_enable_interrupts(struct amdgpu_device *adev)
61 {
62 	u32 ih_cntl = RREG32(mmIH_CNTL);
63 	u32 ih_rb_cntl = RREG32(mmIH_RB_CNTL);
64 
65 	ih_cntl = REG_SET_FIELD(ih_cntl, IH_CNTL, ENABLE_INTR, 1);
66 	ih_rb_cntl = REG_SET_FIELD(ih_rb_cntl, IH_RB_CNTL, RB_ENABLE, 1);
67 	WREG32(mmIH_CNTL, ih_cntl);
68 	WREG32(mmIH_RB_CNTL, ih_rb_cntl);
69 	adev->irq.ih.enabled = true;
70 }
71 
72 /**
73  * cz_ih_disable_interrupts - Disable the interrupt ring buffer
74  *
75  * @adev: amdgpu_device pointer
76  *
77  * Disable the interrupt ring buffer (VI).
78  */
79 static void cz_ih_disable_interrupts(struct amdgpu_device *adev)
80 {
81 	u32 ih_rb_cntl = RREG32(mmIH_RB_CNTL);
82 	u32 ih_cntl = RREG32(mmIH_CNTL);
83 
84 	ih_rb_cntl = REG_SET_FIELD(ih_rb_cntl, IH_RB_CNTL, RB_ENABLE, 0);
85 	ih_cntl = REG_SET_FIELD(ih_cntl, IH_CNTL, ENABLE_INTR, 0);
86 	WREG32(mmIH_RB_CNTL, ih_rb_cntl);
87 	WREG32(mmIH_CNTL, ih_cntl);
88 	/* set rptr, wptr to 0 */
89 	WREG32(mmIH_RB_RPTR, 0);
90 	WREG32(mmIH_RB_WPTR, 0);
91 	adev->irq.ih.enabled = false;
92 	adev->irq.ih.rptr = 0;
93 }
94 
95 /**
96  * cz_ih_irq_init - init and enable the interrupt ring
97  *
98  * @adev: amdgpu_device pointer
99  *
100  * Allocate a ring buffer for the interrupt controller,
101  * enable the RLC, disable interrupts, enable the IH
102  * ring buffer and enable it (VI).
103  * Called at device load and reume.
104  * Returns 0 for success, errors for failure.
105  */
106 static int cz_ih_irq_init(struct amdgpu_device *adev)
107 {
108 	struct amdgpu_ih_ring *ih = &adev->irq.ih;
109 	u32 interrupt_cntl, ih_cntl, ih_rb_cntl;
110 	int rb_bufsz;
111 
112 	/* disable irqs */
113 	cz_ih_disable_interrupts(adev);
114 
115 	/* setup interrupt control */
116 	WREG32(mmINTERRUPT_CNTL2, adev->dummy_page_addr >> 8);
117 	interrupt_cntl = RREG32(mmINTERRUPT_CNTL);
118 	/* INTERRUPT_CNTL__IH_DUMMY_RD_OVERRIDE_MASK=0 - dummy read disabled with msi, enabled without msi
119 	 * INTERRUPT_CNTL__IH_DUMMY_RD_OVERRIDE_MASK=1 - dummy read controlled by IH_DUMMY_RD_EN
120 	 */
121 	interrupt_cntl = REG_SET_FIELD(interrupt_cntl, INTERRUPT_CNTL, IH_DUMMY_RD_OVERRIDE, 0);
122 	/* INTERRUPT_CNTL__IH_REQ_NONSNOOP_EN_MASK=1 if ring is in non-cacheable memory, e.g., vram */
123 	interrupt_cntl = REG_SET_FIELD(interrupt_cntl, INTERRUPT_CNTL, IH_REQ_NONSNOOP_EN, 0);
124 	WREG32(mmINTERRUPT_CNTL, interrupt_cntl);
125 
126 	/* Ring Buffer base. [39:8] of 40-bit address of the beginning of the ring buffer*/
127 	WREG32(mmIH_RB_BASE, adev->irq.ih.gpu_addr >> 8);
128 
129 	rb_bufsz = order_base_2(adev->irq.ih.ring_size / 4);
130 	ih_rb_cntl = REG_SET_FIELD(0, IH_RB_CNTL, WPTR_OVERFLOW_ENABLE, 1);
131 	ih_rb_cntl = REG_SET_FIELD(ih_rb_cntl, IH_RB_CNTL, WPTR_OVERFLOW_CLEAR, 1);
132 	ih_rb_cntl = REG_SET_FIELD(ih_rb_cntl, IH_RB_CNTL, RB_SIZE, rb_bufsz);
133 
134 	/* Ring Buffer write pointer writeback. If enabled, IH_RB_WPTR register value is written to memory */
135 	ih_rb_cntl = REG_SET_FIELD(ih_rb_cntl, IH_RB_CNTL, WPTR_WRITEBACK_ENABLE, 1);
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 	WREG32(mmIH_RB_CNTL, ih_rb_cntl);
142 
143 	/* set rptr, wptr to 0 */
144 	WREG32(mmIH_RB_RPTR, 0);
145 	WREG32(mmIH_RB_WPTR, 0);
146 
147 	/* Default settings for IH_CNTL (disabled at first) */
148 	ih_cntl = RREG32(mmIH_CNTL);
149 	ih_cntl = REG_SET_FIELD(ih_cntl, IH_CNTL, MC_VMID, 0);
150 
151 	if (adev->irq.msi_enabled)
152 		ih_cntl = REG_SET_FIELD(ih_cntl, IH_CNTL, RPTR_REARM, 1);
153 	WREG32(mmIH_CNTL, ih_cntl);
154 
155 	pci_set_master(adev->pdev);
156 
157 	/* enable interrupts */
158 	cz_ih_enable_interrupts(adev);
159 
160 	return 0;
161 }
162 
163 /**
164  * cz_ih_irq_disable - disable interrupts
165  *
166  * @adev: amdgpu_device pointer
167  *
168  * Disable interrupts on the hw (VI).
169  */
170 static void cz_ih_irq_disable(struct amdgpu_device *adev)
171 {
172 	cz_ih_disable_interrupts(adev);
173 
174 	/* Wait and acknowledge irq */
175 	mdelay(1);
176 }
177 
178 /**
179  * cz_ih_get_wptr - get the IH ring buffer wptr
180  *
181  * @adev: amdgpu_device pointer
182  * @ih: IH ring buffer to fetch wptr
183  *
184  * Get the IH ring buffer wptr from either the register
185  * or the writeback memory buffer (VI).  Also check for
186  * ring buffer overflow and deal with it.
187  * Used by cz_irq_process(VI).
188  * Returns the value of the wptr.
189  */
190 static u32 cz_ih_get_wptr(struct amdgpu_device *adev,
191 			  struct amdgpu_ih_ring *ih)
192 {
193 	u32 wptr, tmp;
194 
195 	wptr = le32_to_cpu(*ih->wptr_cpu);
196 
197 	if (!REG_GET_FIELD(wptr, IH_RB_WPTR, RB_OVERFLOW))
198 		goto out;
199 
200 	/* Double check that the overflow wasn't already cleared. */
201 	wptr = RREG32(mmIH_RB_WPTR);
202 
203 	if (!REG_GET_FIELD(wptr, IH_RB_WPTR, RB_OVERFLOW))
204 		goto out;
205 
206 	wptr = REG_SET_FIELD(wptr, IH_RB_WPTR, RB_OVERFLOW, 0);
207 
208 	/* When a ring buffer overflow happen start parsing interrupt
209 	 * from the last not overwritten vector (wptr + 16). Hopefully
210 	 * this should allow us to catchup.
211 	 */
212 	dev_warn(adev->dev, "IH ring buffer overflow (0x%08X, 0x%08X, 0x%08X)\n",
213 		wptr, ih->rptr, (wptr + 16) & ih->ptr_mask);
214 	ih->rptr = (wptr + 16) & ih->ptr_mask;
215 	tmp = RREG32(mmIH_RB_CNTL);
216 	tmp = REG_SET_FIELD(tmp, IH_RB_CNTL, WPTR_OVERFLOW_CLEAR, 1);
217 	WREG32(mmIH_RB_CNTL, tmp);
218 
219 	/* Unset the CLEAR_OVERFLOW bit immediately so new overflows
220 	 * can be detected.
221 	 */
222 	tmp = REG_SET_FIELD(tmp, IH_RB_CNTL, WPTR_OVERFLOW_CLEAR, 0);
223 	WREG32(mmIH_RB_CNTL, tmp);
224 
225 out:
226 	return (wptr & ih->ptr_mask);
227 }
228 
229 /**
230  * cz_ih_decode_iv - decode an interrupt vector
231  *
232  * @adev: amdgpu_device pointer
233  * @ih: IH ring buffer to decode
234  * @entry: IV entry to place decoded information into
235  *
236  * Decodes the interrupt vector at the current rptr
237  * position and also advance the position.
238  */
239 static void cz_ih_decode_iv(struct amdgpu_device *adev,
240 			    struct amdgpu_ih_ring *ih,
241 			    struct amdgpu_iv_entry *entry)
242 {
243 	/* wptr/rptr are in bytes! */
244 	u32 ring_index = ih->rptr >> 2;
245 	uint32_t dw[4];
246 
247 	dw[0] = le32_to_cpu(ih->ring[ring_index + 0]);
248 	dw[1] = le32_to_cpu(ih->ring[ring_index + 1]);
249 	dw[2] = le32_to_cpu(ih->ring[ring_index + 2]);
250 	dw[3] = le32_to_cpu(ih->ring[ring_index + 3]);
251 
252 	entry->client_id = AMDGPU_IRQ_CLIENTID_LEGACY;
253 	entry->src_id = dw[0] & 0xff;
254 	entry->src_data[0] = dw[1] & 0xfffffff;
255 	entry->ring_id = dw[2] & 0xff;
256 	entry->vmid = (dw[2] >> 8) & 0xff;
257 	entry->pasid = (dw[2] >> 16) & 0xffff;
258 
259 	/* wptr/rptr are in bytes! */
260 	ih->rptr += 16;
261 }
262 
263 /**
264  * cz_ih_set_rptr - set the IH ring buffer rptr
265  *
266  * @adev: amdgpu_device pointer
267  * @ih: IH ring buffer to set rptr
268  *
269  * Set the IH ring buffer rptr.
270  */
271 static void cz_ih_set_rptr(struct amdgpu_device *adev,
272 			   struct amdgpu_ih_ring *ih)
273 {
274 	WREG32(mmIH_RB_RPTR, ih->rptr);
275 }
276 
277 static int cz_ih_early_init(void *handle)
278 {
279 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
280 	int ret;
281 
282 	ret = amdgpu_irq_add_domain(adev);
283 	if (ret)
284 		return ret;
285 
286 	cz_ih_set_interrupt_funcs(adev);
287 
288 	return 0;
289 }
290 
291 static int cz_ih_sw_init(void *handle)
292 {
293 	int r;
294 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
295 
296 	r = amdgpu_ih_ring_init(adev, &adev->irq.ih, 64 * 1024, false);
297 	if (r)
298 		return r;
299 
300 	r = amdgpu_irq_init(adev);
301 
302 	return r;
303 }
304 
305 static int cz_ih_sw_fini(void *handle)
306 {
307 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
308 
309 	amdgpu_irq_fini_sw(adev);
310 	amdgpu_irq_remove_domain(adev);
311 
312 	return 0;
313 }
314 
315 static int cz_ih_hw_init(void *handle)
316 {
317 	int r;
318 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
319 
320 	r = cz_ih_irq_init(adev);
321 	if (r)
322 		return r;
323 
324 	return 0;
325 }
326 
327 static int cz_ih_hw_fini(void *handle)
328 {
329 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
330 
331 	cz_ih_irq_disable(adev);
332 
333 	return 0;
334 }
335 
336 static int cz_ih_suspend(void *handle)
337 {
338 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
339 
340 	return cz_ih_hw_fini(adev);
341 }
342 
343 static int cz_ih_resume(void *handle)
344 {
345 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
346 
347 	return cz_ih_hw_init(adev);
348 }
349 
350 static bool cz_ih_is_idle(void *handle)
351 {
352 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
353 	u32 tmp = RREG32(mmSRBM_STATUS);
354 
355 	if (REG_GET_FIELD(tmp, SRBM_STATUS, IH_BUSY))
356 		return false;
357 
358 	return true;
359 }
360 
361 static int cz_ih_wait_for_idle(void *handle)
362 {
363 	unsigned i;
364 	u32 tmp;
365 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
366 
367 	for (i = 0; i < adev->usec_timeout; i++) {
368 		/* read MC_STATUS */
369 		tmp = RREG32(mmSRBM_STATUS);
370 		if (!REG_GET_FIELD(tmp, SRBM_STATUS, IH_BUSY))
371 			return 0;
372 		udelay(1);
373 	}
374 	return -ETIMEDOUT;
375 }
376 
377 static int cz_ih_soft_reset(void *handle)
378 {
379 	u32 srbm_soft_reset = 0;
380 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
381 	u32 tmp = RREG32(mmSRBM_STATUS);
382 
383 	if (tmp & SRBM_STATUS__IH_BUSY_MASK)
384 		srbm_soft_reset = REG_SET_FIELD(srbm_soft_reset, SRBM_SOFT_RESET,
385 						SOFT_RESET_IH, 1);
386 
387 	if (srbm_soft_reset) {
388 		tmp = RREG32(mmSRBM_SOFT_RESET);
389 		tmp |= srbm_soft_reset;
390 		dev_info(adev->dev, "SRBM_SOFT_RESET=0x%08X\n", tmp);
391 		WREG32(mmSRBM_SOFT_RESET, tmp);
392 		tmp = RREG32(mmSRBM_SOFT_RESET);
393 
394 		udelay(50);
395 
396 		tmp &= ~srbm_soft_reset;
397 		WREG32(mmSRBM_SOFT_RESET, tmp);
398 		tmp = RREG32(mmSRBM_SOFT_RESET);
399 
400 		/* Wait a little for things to settle down */
401 		udelay(50);
402 	}
403 
404 	return 0;
405 }
406 
407 static int cz_ih_set_clockgating_state(void *handle,
408 					  enum amd_clockgating_state state)
409 {
410 	// TODO
411 	return 0;
412 }
413 
414 static int cz_ih_set_powergating_state(void *handle,
415 					  enum amd_powergating_state state)
416 {
417 	// TODO
418 	return 0;
419 }
420 
421 static const struct amd_ip_funcs cz_ih_ip_funcs = {
422 	.name = "cz_ih",
423 	.early_init = cz_ih_early_init,
424 	.late_init = NULL,
425 	.sw_init = cz_ih_sw_init,
426 	.sw_fini = cz_ih_sw_fini,
427 	.hw_init = cz_ih_hw_init,
428 	.hw_fini = cz_ih_hw_fini,
429 	.suspend = cz_ih_suspend,
430 	.resume = cz_ih_resume,
431 	.is_idle = cz_ih_is_idle,
432 	.wait_for_idle = cz_ih_wait_for_idle,
433 	.soft_reset = cz_ih_soft_reset,
434 	.set_clockgating_state = cz_ih_set_clockgating_state,
435 	.set_powergating_state = cz_ih_set_powergating_state,
436 };
437 
438 static const struct amdgpu_ih_funcs cz_ih_funcs = {
439 	.get_wptr = cz_ih_get_wptr,
440 	.decode_iv = cz_ih_decode_iv,
441 	.set_rptr = cz_ih_set_rptr
442 };
443 
444 static void cz_ih_set_interrupt_funcs(struct amdgpu_device *adev)
445 {
446 	adev->irq.ih_funcs = &cz_ih_funcs;
447 }
448 
449 const struct amdgpu_ip_block_version cz_ih_ip_block =
450 {
451 	.type = AMD_IP_BLOCK_TYPE_IH,
452 	.major = 3,
453 	.minor = 0,
454 	.rev = 0,
455 	.funcs = &cz_ih_ip_funcs,
456 };
457