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
51static 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 */
60static 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 */
79static 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 */
106static 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(dev: 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 */
170static 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 */
190static 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
225out:
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 */
239static 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 */
271static 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
277static 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
291static 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, ih: &adev->irq.ih, ring_size: 64 * 1024, use_bus_addr: false);
297 if (r)
298 return r;
299
300 r = amdgpu_irq_init(adev);
301
302 return r;
303}
304
305static 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
315static 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
327static 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
336static int cz_ih_suspend(void *handle)
337{
338 struct amdgpu_device *adev = (struct amdgpu_device *)handle;
339
340 return cz_ih_hw_fini(handle: adev);
341}
342
343static int cz_ih_resume(void *handle)
344{
345 struct amdgpu_device *adev = (struct amdgpu_device *)handle;
346
347 return cz_ih_hw_init(handle: adev);
348}
349
350static 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
361static 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
377static 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
407static int cz_ih_set_clockgating_state(void *handle,
408 enum amd_clockgating_state state)
409{
410 // TODO
411 return 0;
412}
413
414static int cz_ih_set_powergating_state(void *handle,
415 enum amd_powergating_state state)
416{
417 // TODO
418 return 0;
419}
420
421static 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
438static 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
444static void cz_ih_set_interrupt_funcs(struct amdgpu_device *adev)
445{
446 adev->irq.ih_funcs = &cz_ih_funcs;
447}
448
449const 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

source code of linux/drivers/gpu/drm/amd/amdgpu/cz_ih.c