xref: /netbsd-src/sys/external/bsd/drm2/dist/drm/amd/display/dc/dce/amdgpu_dce_abm.c (revision 7e2fc62e3ca81c7bfa1d3c8d0691ddccf389ac4a)
1 /*	$NetBSD: amdgpu_dce_abm.c,v 1.3 2021/12/19 11:23:26 riastradh Exp $	*/
2 
3 /*
4  * Copyright 2012-16 Advanced Micro Devices, Inc.
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a
7  * copy of this software and associated documentation files (the "Software"),
8  * to deal in the Software without restriction, including without limitation
9  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10  * and/or sell copies of the Software, and to permit persons to whom the
11  * Software is furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
19  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
20  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
21  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
22  * OTHER DEALINGS IN THE SOFTWARE.
23  *
24  * Authors: AMD
25  *
26  */
27 
28 #include <sys/cdefs.h>
29 __KERNEL_RCSID(0, "$NetBSD: amdgpu_dce_abm.c,v 1.3 2021/12/19 11:23:26 riastradh Exp $");
30 
31 #include <linux/slab.h>
32 
33 #include "dce_abm.h"
34 #include "dm_services.h"
35 #include "reg_helper.h"
36 #include "fixed31_32.h"
37 #include "dc.h"
38 
39 #include "atom.h"
40 
41 
42 #define TO_DCE_ABM(abm)\
43 	container_of(abm, struct dce_abm, base)
44 
45 #define REG(reg) \
46 	(abm_dce->regs->reg)
47 
48 #undef FN
49 #define FN(reg_name, field_name) \
50 	abm_dce->abm_shift->field_name, abm_dce->abm_mask->field_name
51 
52 #define DC_LOGGER \
53 	abm->ctx->logger
54 #define CTX \
55 	abm_dce->base.ctx
56 
57 #define MCP_ABM_LEVEL_SET 0x65
58 #define MCP_ABM_PIPE_SET 0x66
59 #define MCP_BL_SET 0x67
60 
61 #define MCP_DISABLE_ABM_IMMEDIATELY 255
62 
dce_abm_set_pipe(struct abm * abm,uint32_t controller_id)63 static bool dce_abm_set_pipe(struct abm *abm, uint32_t controller_id)
64 {
65 	struct dce_abm *abm_dce = TO_DCE_ABM(abm);
66 	uint32_t rampingBoundary = 0xFFFF;
67 
68 	if (abm->dmcu_is_running == false)
69 		return true;
70 
71 	REG_WAIT(MASTER_COMM_CNTL_REG, MASTER_COMM_INTERRUPT, 0,
72 			1, 80000);
73 
74 	/* set ramping boundary */
75 	REG_WRITE(MASTER_COMM_DATA_REG1, rampingBoundary);
76 
77 	/* setDMCUParam_Pipe */
78 	REG_UPDATE_2(MASTER_COMM_CMD_REG,
79 			MASTER_COMM_CMD_REG_BYTE0, MCP_ABM_PIPE_SET,
80 			MASTER_COMM_CMD_REG_BYTE1, controller_id);
81 
82 	/* notifyDMCUMsg */
83 	REG_UPDATE(MASTER_COMM_CNTL_REG, MASTER_COMM_INTERRUPT, 1);
84 
85 	REG_WAIT(MASTER_COMM_CNTL_REG, MASTER_COMM_INTERRUPT, 0,
86 			1, 80000);
87 
88 	return true;
89 }
90 
calculate_16_bit_backlight_from_pwm(struct dce_abm * abm_dce)91 static unsigned int calculate_16_bit_backlight_from_pwm(struct dce_abm *abm_dce)
92 {
93 	uint64_t current_backlight;
94 	uint32_t round_result;
95 	uint32_t pwm_period_cntl __unused, bl_period, bl_int_count;
96 	uint32_t bl_pwm_cntl __unused, bl_pwm, fractional_duty_cycle_en;
97 	uint32_t bl_period_mask, bl_pwm_mask;
98 
99 	pwm_period_cntl = REG_READ(BL_PWM_PERIOD_CNTL);
100 	REG_GET(BL_PWM_PERIOD_CNTL, BL_PWM_PERIOD, &bl_period);
101 	REG_GET(BL_PWM_PERIOD_CNTL, BL_PWM_PERIOD_BITCNT, &bl_int_count);
102 
103 	bl_pwm_cntl = REG_READ(BL_PWM_CNTL);
104 	REG_GET(BL_PWM_CNTL, BL_ACTIVE_INT_FRAC_CNT, (uint32_t *)(&bl_pwm));
105 	REG_GET(BL_PWM_CNTL, BL_PWM_FRACTIONAL_EN, &fractional_duty_cycle_en);
106 
107 	if (bl_int_count == 0)
108 		bl_int_count = 16;
109 
110 	bl_period_mask = (1 << bl_int_count) - 1;
111 	bl_period &= bl_period_mask;
112 
113 	bl_pwm_mask = bl_period_mask << (16 - bl_int_count);
114 
115 	if (fractional_duty_cycle_en == 0)
116 		bl_pwm &= bl_pwm_mask;
117 	else
118 		bl_pwm &= 0xFFFF;
119 
120 	current_backlight = bl_pwm << (1 + bl_int_count);
121 
122 	if (bl_period == 0)
123 		bl_period = 0xFFFF;
124 
125 	current_backlight = div_u64(current_backlight, bl_period);
126 	current_backlight = (current_backlight + 1) >> 1;
127 
128 	current_backlight = (uint64_t)(current_backlight) * bl_period;
129 
130 	round_result = (uint32_t)(current_backlight & 0xFFFFFFFF);
131 
132 	round_result = (round_result >> (bl_int_count-1)) & 1;
133 
134 	current_backlight >>= bl_int_count;
135 	current_backlight += round_result;
136 
137 	return (uint32_t)(current_backlight);
138 }
139 
driver_set_backlight_level(struct dce_abm * abm_dce,uint32_t backlight_pwm_u16_16)140 static void driver_set_backlight_level(struct dce_abm *abm_dce,
141 		uint32_t backlight_pwm_u16_16)
142 {
143 	uint32_t backlight_16bit;
144 	uint32_t masked_pwm_period;
145 	uint8_t bit_count;
146 	uint64_t active_duty_cycle;
147 	uint32_t pwm_period_bitcnt;
148 
149 	/*
150 	 * 1. Find  16 bit backlight active duty cycle, where 0 <= backlight
151 	 * active duty cycle <= backlight period
152 	 */
153 
154 	/* 1.1 Apply bitmask for backlight period value based on value of BITCNT
155 	 */
156 	REG_GET_2(BL_PWM_PERIOD_CNTL,
157 			BL_PWM_PERIOD_BITCNT, &pwm_period_bitcnt,
158 			BL_PWM_PERIOD, &masked_pwm_period);
159 
160 	if (pwm_period_bitcnt == 0)
161 		bit_count = 16;
162 	else
163 		bit_count = pwm_period_bitcnt;
164 
165 	/* e.g. maskedPwmPeriod = 0x24 when bitCount is 6 */
166 	masked_pwm_period = masked_pwm_period & ((1 << bit_count) - 1);
167 
168 	/* 1.2 Calculate integer active duty cycle required upper 16 bits
169 	 * contain integer component, lower 16 bits contain fractional component
170 	 * of active duty cycle e.g. 0x21BDC0 = 0xEFF0 * 0x24
171 	 */
172 	active_duty_cycle = backlight_pwm_u16_16 * masked_pwm_period;
173 
174 	/* 1.3 Calculate 16 bit active duty cycle from integer and fractional
175 	 * components shift by bitCount then mask 16 bits and add rounding bit
176 	 * from MSB of fraction e.g. 0x86F7 = ((0x21BDC0 >> 6) & 0xFFF) + 0
177 	 */
178 	backlight_16bit = active_duty_cycle >> bit_count;
179 	backlight_16bit &= 0xFFFF;
180 	backlight_16bit += (active_duty_cycle >> (bit_count - 1)) & 0x1;
181 
182 	/*
183 	 * 2. Program register with updated value
184 	 */
185 
186 	/* 2.1 Lock group 2 backlight registers */
187 
188 	REG_UPDATE_2(BL_PWM_GRP1_REG_LOCK,
189 			BL_PWM_GRP1_IGNORE_MASTER_LOCK_EN, 1,
190 			BL_PWM_GRP1_REG_LOCK, 1);
191 
192 	// 2.2 Write new active duty cycle
193 	REG_UPDATE(BL_PWM_CNTL, BL_ACTIVE_INT_FRAC_CNT, backlight_16bit);
194 
195 	/* 2.3 Unlock group 2 backlight registers */
196 	REG_UPDATE(BL_PWM_GRP1_REG_LOCK,
197 			BL_PWM_GRP1_REG_LOCK, 0);
198 
199 	/* 3 Wait for pending bit to be cleared */
200 	REG_WAIT(BL_PWM_GRP1_REG_LOCK,
201 			BL_PWM_GRP1_REG_UPDATE_PENDING, 0,
202 			1, 10000);
203 }
204 
dmcu_set_backlight_level(struct dce_abm * abm_dce,uint32_t backlight_pwm_u16_16,uint32_t frame_ramp,uint32_t controller_id)205 static void dmcu_set_backlight_level(
206 	struct dce_abm *abm_dce,
207 	uint32_t backlight_pwm_u16_16,
208 	uint32_t frame_ramp,
209 	uint32_t controller_id)
210 {
211 	unsigned int backlight_8_bit = 0;
212 	uint32_t s2;
213 
214 	if (backlight_pwm_u16_16 & 0x10000)
215 		// Check for max backlight condition
216 		backlight_8_bit = 0xFF;
217 	else
218 		// Take MSB of fractional part since backlight is not max
219 		backlight_8_bit = (backlight_pwm_u16_16 >> 8) & 0xFF;
220 
221 	dce_abm_set_pipe(&abm_dce->base, controller_id);
222 
223 	/* waitDMCUReadyForCmd */
224 	REG_WAIT(MASTER_COMM_CNTL_REG, MASTER_COMM_INTERRUPT,
225 			0, 1, 80000);
226 
227 	/* setDMCUParam_BL */
228 	REG_UPDATE(BL1_PWM_USER_LEVEL, BL1_PWM_USER_LEVEL, backlight_pwm_u16_16);
229 
230 	/* write ramp */
231 	if (controller_id == 0)
232 		frame_ramp = 0;
233 	REG_WRITE(MASTER_COMM_DATA_REG1, frame_ramp);
234 
235 	/* setDMCUParam_Cmd */
236 	REG_UPDATE(MASTER_COMM_CMD_REG, MASTER_COMM_CMD_REG_BYTE0, MCP_BL_SET);
237 
238 	/* notifyDMCUMsg */
239 	REG_UPDATE(MASTER_COMM_CNTL_REG, MASTER_COMM_INTERRUPT, 1);
240 
241 	/* UpdateRequestedBacklightLevel */
242 	s2 = REG_READ(BIOS_SCRATCH_2);
243 
244 	s2 &= ~ATOM_S2_CURRENT_BL_LEVEL_MASK;
245 	backlight_8_bit &= (ATOM_S2_CURRENT_BL_LEVEL_MASK >>
246 				ATOM_S2_CURRENT_BL_LEVEL_SHIFT);
247 	s2 |= (backlight_8_bit << ATOM_S2_CURRENT_BL_LEVEL_SHIFT);
248 
249 	REG_WRITE(BIOS_SCRATCH_2, s2);
250 
251 	/* waitDMCUReadyForCmd */
252 	REG_WAIT(MASTER_COMM_CNTL_REG, MASTER_COMM_INTERRUPT,
253 			0, 1, 80000);
254 }
255 
dce_abm_init(struct abm * abm)256 static void dce_abm_init(struct abm *abm)
257 {
258 	struct dce_abm *abm_dce = TO_DCE_ABM(abm);
259 	unsigned int backlight = calculate_16_bit_backlight_from_pwm(abm_dce);
260 
261 	REG_WRITE(DC_ABM1_HG_SAMPLE_RATE, 0x103);
262 	REG_WRITE(DC_ABM1_HG_SAMPLE_RATE, 0x101);
263 	REG_WRITE(DC_ABM1_LS_SAMPLE_RATE, 0x103);
264 	REG_WRITE(DC_ABM1_LS_SAMPLE_RATE, 0x101);
265 	REG_WRITE(BL1_PWM_BL_UPDATE_SAMPLE_RATE, 0x101);
266 
267 	REG_SET_3(DC_ABM1_HG_MISC_CTRL, 0,
268 			ABM1_HG_NUM_OF_BINS_SEL, 0,
269 			ABM1_HG_VMAX_SEL, 1,
270 			ABM1_HG_BIN_BITWIDTH_SIZE_SEL, 0);
271 
272 	REG_SET_3(DC_ABM1_IPCSC_COEFF_SEL, 0,
273 			ABM1_IPCSC_COEFF_SEL_R, 2,
274 			ABM1_IPCSC_COEFF_SEL_G, 4,
275 			ABM1_IPCSC_COEFF_SEL_B, 2);
276 
277 	REG_UPDATE(BL1_PWM_CURRENT_ABM_LEVEL,
278 			BL1_PWM_CURRENT_ABM_LEVEL, backlight);
279 
280 	REG_UPDATE(BL1_PWM_TARGET_ABM_LEVEL,
281 			BL1_PWM_TARGET_ABM_LEVEL, backlight);
282 
283 	REG_UPDATE(BL1_PWM_USER_LEVEL,
284 			BL1_PWM_USER_LEVEL, backlight);
285 
286 	REG_UPDATE_2(DC_ABM1_LS_MIN_MAX_PIXEL_VALUE_THRES,
287 			ABM1_LS_MIN_PIXEL_VALUE_THRES, 0,
288 			ABM1_LS_MAX_PIXEL_VALUE_THRES, 1000);
289 
290 	REG_SET_3(DC_ABM1_HGLS_REG_READ_PROGRESS, 0,
291 			ABM1_HG_REG_READ_MISSED_FRAME_CLEAR, 1,
292 			ABM1_LS_REG_READ_MISSED_FRAME_CLEAR, 1,
293 			ABM1_BL_REG_READ_MISSED_FRAME_CLEAR, 1);
294 }
295 
dce_abm_get_current_backlight(struct abm * abm)296 static unsigned int dce_abm_get_current_backlight(struct abm *abm)
297 {
298 	struct dce_abm *abm_dce = TO_DCE_ABM(abm);
299 	unsigned int backlight = REG_READ(BL1_PWM_CURRENT_ABM_LEVEL);
300 
301 	/* return backlight in hardware format which is unsigned 17 bits, with
302 	 * 1 bit integer and 16 bit fractional
303 	 */
304 	return backlight;
305 }
306 
dce_abm_get_target_backlight(struct abm * abm)307 static unsigned int dce_abm_get_target_backlight(struct abm *abm)
308 {
309 	struct dce_abm *abm_dce = TO_DCE_ABM(abm);
310 	unsigned int backlight = REG_READ(BL1_PWM_TARGET_ABM_LEVEL);
311 
312 	/* return backlight in hardware format which is unsigned 17 bits, with
313 	 * 1 bit integer and 16 bit fractional
314 	 */
315 	return backlight;
316 }
317 
dce_abm_set_level(struct abm * abm,uint32_t level)318 static bool dce_abm_set_level(struct abm *abm, uint32_t level)
319 {
320 	struct dce_abm *abm_dce = TO_DCE_ABM(abm);
321 
322 	if (abm->dmcu_is_running == false)
323 		return true;
324 
325 	REG_WAIT(MASTER_COMM_CNTL_REG, MASTER_COMM_INTERRUPT, 0,
326 			1, 80000);
327 
328 	/* setDMCUParam_ABMLevel */
329 	REG_UPDATE_2(MASTER_COMM_CMD_REG,
330 			MASTER_COMM_CMD_REG_BYTE0, MCP_ABM_LEVEL_SET,
331 			MASTER_COMM_CMD_REG_BYTE2, level);
332 
333 	/* notifyDMCUMsg */
334 	REG_UPDATE(MASTER_COMM_CNTL_REG, MASTER_COMM_INTERRUPT, 1);
335 
336 	return true;
337 }
338 
dce_abm_immediate_disable(struct abm * abm)339 static bool dce_abm_immediate_disable(struct abm *abm)
340 {
341 	struct dce_abm *abm_dce = TO_DCE_ABM(abm);
342 
343 	if (abm->dmcu_is_running == false)
344 		return true;
345 
346 	dce_abm_set_pipe(abm, MCP_DISABLE_ABM_IMMEDIATELY);
347 
348 	abm->stored_backlight_registers.BL_PWM_CNTL =
349 		REG_READ(BL_PWM_CNTL);
350 	abm->stored_backlight_registers.BL_PWM_CNTL2 =
351 		REG_READ(BL_PWM_CNTL2);
352 	abm->stored_backlight_registers.BL_PWM_PERIOD_CNTL =
353 		REG_READ(BL_PWM_PERIOD_CNTL);
354 
355 	REG_GET(LVTMA_PWRSEQ_REF_DIV, BL_PWM_REF_DIV,
356 		&abm->stored_backlight_registers.LVTMA_PWRSEQ_REF_DIV_BL_PWM_REF_DIV);
357 	return true;
358 }
359 
dce_abm_init_backlight(struct abm * abm)360 static bool dce_abm_init_backlight(struct abm *abm)
361 {
362 	struct dce_abm *abm_dce = TO_DCE_ABM(abm);
363 	uint32_t value;
364 
365 	/* It must not be 0, so we have to restore them
366 	 * Bios bug w/a - period resets to zero,
367 	 * restoring to cache values which is always correct
368 	 */
369 	REG_GET(BL_PWM_CNTL, BL_ACTIVE_INT_FRAC_CNT, &value);
370 	if (value == 0 || value == 1) {
371 		if (abm->stored_backlight_registers.BL_PWM_CNTL != 0) {
372 			REG_WRITE(BL_PWM_CNTL,
373 				abm->stored_backlight_registers.BL_PWM_CNTL);
374 			REG_WRITE(BL_PWM_CNTL2,
375 				abm->stored_backlight_registers.BL_PWM_CNTL2);
376 			REG_WRITE(BL_PWM_PERIOD_CNTL,
377 				abm->stored_backlight_registers.BL_PWM_PERIOD_CNTL);
378 			REG_UPDATE(LVTMA_PWRSEQ_REF_DIV,
379 				BL_PWM_REF_DIV,
380 				abm->stored_backlight_registers.
381 				LVTMA_PWRSEQ_REF_DIV_BL_PWM_REF_DIV);
382 		} else {
383 			/* TODO: Note: This should not really happen since VBIOS
384 			 * should have initialized PWM registers on boot.
385 			 */
386 			REG_WRITE(BL_PWM_CNTL, 0xC000FA00);
387 			REG_WRITE(BL_PWM_PERIOD_CNTL, 0x000C0FA0);
388 		}
389 	} else {
390 		abm->stored_backlight_registers.BL_PWM_CNTL =
391 				REG_READ(BL_PWM_CNTL);
392 		abm->stored_backlight_registers.BL_PWM_CNTL2 =
393 				REG_READ(BL_PWM_CNTL2);
394 		abm->stored_backlight_registers.BL_PWM_PERIOD_CNTL =
395 				REG_READ(BL_PWM_PERIOD_CNTL);
396 
397 		REG_GET(LVTMA_PWRSEQ_REF_DIV, BL_PWM_REF_DIV,
398 				&abm->stored_backlight_registers.
399 				LVTMA_PWRSEQ_REF_DIV_BL_PWM_REF_DIV);
400 	}
401 
402 	/* Have driver take backlight control
403 	 * TakeBacklightControl(true)
404 	 */
405 	value = REG_READ(BIOS_SCRATCH_2);
406 	value |= ATOM_S2_VRI_BRIGHT_ENABLE;
407 	REG_WRITE(BIOS_SCRATCH_2, value);
408 
409 	/* Enable the backlight output */
410 	REG_UPDATE(BL_PWM_CNTL, BL_PWM_EN, 1);
411 
412 	/* Disable fractional pwm if configured */
413 	REG_UPDATE(BL_PWM_CNTL, BL_PWM_FRACTIONAL_EN,
414 		   abm->ctx->dc->config.disable_fractional_pwm ? 0 : 1);
415 
416 	/* Unlock group 2 backlight registers */
417 	REG_UPDATE(BL_PWM_GRP1_REG_LOCK,
418 			BL_PWM_GRP1_REG_LOCK, 0);
419 
420 	return true;
421 }
422 
dce_abm_set_backlight_level_pwm(struct abm * abm,unsigned int backlight_pwm_u16_16,unsigned int frame_ramp,unsigned int controller_id,bool use_smooth_brightness)423 static bool dce_abm_set_backlight_level_pwm(
424 		struct abm *abm,
425 		unsigned int backlight_pwm_u16_16,
426 		unsigned int frame_ramp,
427 		unsigned int controller_id,
428 		bool use_smooth_brightness)
429 {
430 	struct dce_abm *abm_dce = TO_DCE_ABM(abm);
431 
432 	DC_LOG_BACKLIGHT("New Backlight level: %d (0x%X)\n",
433 			backlight_pwm_u16_16, backlight_pwm_u16_16);
434 
435 	/* If DMCU is in reset state, DMCU is uninitialized */
436 	if (use_smooth_brightness)
437 		dmcu_set_backlight_level(abm_dce,
438 				backlight_pwm_u16_16,
439 				frame_ramp,
440 				controller_id);
441 	else
442 		driver_set_backlight_level(abm_dce, backlight_pwm_u16_16);
443 
444 	return true;
445 }
446 
447 static const struct abm_funcs dce_funcs = {
448 	.abm_init = dce_abm_init,
449 	.set_abm_level = dce_abm_set_level,
450 	.init_backlight = dce_abm_init_backlight,
451 	.set_pipe = dce_abm_set_pipe,
452 	.set_backlight_level_pwm = dce_abm_set_backlight_level_pwm,
453 	.get_current_backlight = dce_abm_get_current_backlight,
454 	.get_target_backlight = dce_abm_get_target_backlight,
455 	.set_abm_immediate_disable = dce_abm_immediate_disable
456 };
457 
dce_abm_construct(struct dce_abm * abm_dce,struct dc_context * ctx,const struct dce_abm_registers * regs,const struct dce_abm_shift * abm_shift,const struct dce_abm_mask * abm_mask)458 static void dce_abm_construct(
459 	struct dce_abm *abm_dce,
460 	struct dc_context *ctx,
461 	const struct dce_abm_registers *regs,
462 	const struct dce_abm_shift *abm_shift,
463 	const struct dce_abm_mask *abm_mask)
464 {
465 	struct abm *base = &abm_dce->base;
466 
467 	base->ctx = ctx;
468 	base->funcs = &dce_funcs;
469 	base->stored_backlight_registers.BL_PWM_CNTL = 0;
470 	base->stored_backlight_registers.BL_PWM_CNTL2 = 0;
471 	base->stored_backlight_registers.BL_PWM_PERIOD_CNTL = 0;
472 	base->stored_backlight_registers.LVTMA_PWRSEQ_REF_DIV_BL_PWM_REF_DIV = 0;
473 	base->dmcu_is_running = false;
474 
475 	abm_dce->regs = regs;
476 	abm_dce->abm_shift = abm_shift;
477 	abm_dce->abm_mask = abm_mask;
478 }
479 
dce_abm_create(struct dc_context * ctx,const struct dce_abm_registers * regs,const struct dce_abm_shift * abm_shift,const struct dce_abm_mask * abm_mask)480 struct abm *dce_abm_create(
481 	struct dc_context *ctx,
482 	const struct dce_abm_registers *regs,
483 	const struct dce_abm_shift *abm_shift,
484 	const struct dce_abm_mask *abm_mask)
485 {
486 	struct dce_abm *abm_dce = kzalloc(sizeof(*abm_dce), GFP_KERNEL);
487 
488 	if (abm_dce == NULL) {
489 		BREAK_TO_DEBUGGER();
490 		return NULL;
491 	}
492 
493 	dce_abm_construct(abm_dce, ctx, regs, abm_shift, abm_mask);
494 
495 	abm_dce->base.funcs = &dce_funcs;
496 
497 	return &abm_dce->base;
498 }
499 
dce_abm_destroy(struct abm ** abm)500 void dce_abm_destroy(struct abm **abm)
501 {
502 	struct dce_abm *abm_dce = TO_DCE_ABM(*abm);
503 
504 	kfree(abm_dce);
505 	*abm = NULL;
506 }
507