1/*
2 * Copyright 2019 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 "smuio/smuio_11_0_0_offset.h"
25#include "smuio/smuio_11_0_0_sh_mask.h"
26
27#include "smu_v11_0_i2c.h"
28#include "amdgpu.h"
29#include "amdgpu_dpm.h"
30#include "soc15_common.h"
31#include <drm/drm_fixed.h>
32#include <drm/drm_drv.h>
33#include "amdgpu_amdkfd.h"
34#include <linux/i2c.h>
35#include <linux/pci.h>
36
37/* error codes */
38#define I2C_OK                0
39#define I2C_NAK_7B_ADDR_NOACK 1
40#define I2C_NAK_TXDATA_NOACK  2
41#define I2C_TIMEOUT           4
42#define I2C_SW_TIMEOUT        8
43#define I2C_ABORT             0x10
44
45#define I2C_X_RESTART         BIT(31)
46
47static void smu_v11_0_i2c_set_clock_gating(struct i2c_adapter *control, bool en)
48{
49	struct amdgpu_smu_i2c_bus *smu_i2c = i2c_get_adapdata(control);
50	struct amdgpu_device *adev = smu_i2c->adev;
51	uint32_t reg = RREG32_SOC15(SMUIO, 0, mmSMUIO_PWRMGT);
52
53	reg = REG_SET_FIELD(reg, SMUIO_PWRMGT, i2c_clk_gate_en, en ? 1 : 0);
54	WREG32_SOC15(SMUIO, 0, mmSMUIO_PWRMGT, reg);
55}
56
57/* The T_I2C_POLL_US is defined as follows:
58 *
59 * "Define a timer interval (t_i2c_poll) equal to 10 times the
60 *  signalling period for the highest I2C transfer speed used in the
61 *  system and supported by DW_apb_i2c. For instance, if the highest
62 *  I2C data transfer mode is 400 kb/s, then t_i2c_poll is 25 us."  --
63 * DesignWare DW_apb_i2c Databook, Version 1.21a, section 3.8.3.1,
64 * page 56, with grammar and syntax corrections.
65 *
66 * Vcc for our device is at 1.8V which puts it at 400 kHz,
67 * see Atmel AT24CM02 datasheet, section 8.3 DC Characteristics table, page 14.
68 *
69 * The procedure to disable the IP block is described in section
70 * 3.8.3 Disabling DW_apb_i2c on page 56.
71 */
72#define I2C_SPEED_MODE_FAST     2
73#define T_I2C_POLL_US           25
74#define I2C_MAX_T_POLL_COUNT    1000
75
76static int smu_v11_0_i2c_enable(struct i2c_adapter *control, bool enable)
77{
78	struct amdgpu_smu_i2c_bus *smu_i2c = i2c_get_adapdata(control);
79	struct amdgpu_device *adev = smu_i2c->adev;
80
81	WREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_ENABLE, enable ? 1 : 0);
82
83	if (!enable) {
84		int ii;
85
86		for (ii = I2C_MAX_T_POLL_COUNT; ii > 0; ii--) {
87			u32 en_stat = RREG32_SOC15(SMUIO,
88						   0,
89						   mmCKSVII2C_IC_ENABLE_STATUS);
90			if (REG_GET_FIELD(en_stat, CKSVII2C_IC_ENABLE_STATUS, IC_EN))
91				udelay(T_I2C_POLL_US);
92			else
93				return I2C_OK;
94		}
95
96		return I2C_ABORT;
97	}
98
99	return I2C_OK;
100}
101
102static void smu_v11_0_i2c_clear_status(struct i2c_adapter *control)
103{
104	struct amdgpu_smu_i2c_bus *smu_i2c = i2c_get_adapdata(control);
105	struct amdgpu_device *adev = smu_i2c->adev;
106	/* do */
107	{
108		RREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_CLR_INTR);
109
110	} /* while (reg_CKSVII2C_ic_clr_intr == 0) */
111}
112
113static void smu_v11_0_i2c_configure(struct i2c_adapter *control)
114{
115	struct amdgpu_smu_i2c_bus *smu_i2c = i2c_get_adapdata(control);
116	struct amdgpu_device *adev = smu_i2c->adev;
117	uint32_t reg = 0;
118
119	reg = REG_SET_FIELD(reg, CKSVII2C_IC_CON, IC_SLAVE_DISABLE, 1);
120	reg = REG_SET_FIELD(reg, CKSVII2C_IC_CON, IC_RESTART_EN, 1);
121	reg = REG_SET_FIELD(reg, CKSVII2C_IC_CON, IC_10BITADDR_MASTER, 0);
122	reg = REG_SET_FIELD(reg, CKSVII2C_IC_CON, IC_10BITADDR_SLAVE, 0);
123	/* The values of IC_MAX_SPEED_MODE are,
124	 * 1: standard mode, 0 - 100 Kb/s,
125	 * 2: fast mode, <= 400 Kb/s, or fast mode plus, <= 1000 Kb/s,
126	 * 3: high speed mode, <= 3.4 Mb/s.
127	 */
128	reg = REG_SET_FIELD(reg, CKSVII2C_IC_CON, IC_MAX_SPEED_MODE,
129			    I2C_SPEED_MODE_FAST);
130	reg = REG_SET_FIELD(reg, CKSVII2C_IC_CON, IC_MASTER_MODE, 1);
131
132	WREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_CON, reg);
133}
134
135static void smu_v11_0_i2c_set_clock(struct i2c_adapter *control)
136{
137	struct amdgpu_smu_i2c_bus *smu_i2c = i2c_get_adapdata(control);
138	struct amdgpu_device *adev = smu_i2c->adev;
139
140	/*
141	 * Standard mode speed, These values are taken from SMUIO MAS,
142	 * but are different from what is given is
143	 * Synopsys spec. The values here are based on assumption
144	 * that refclock is 100MHz
145	 *
146	 * Configuration for standard mode; Speed = 100kbps
147	 * Scale linearly, for now only support standard speed clock
148	 * This will work only with 100M ref clock
149	 *
150	 * TBD:Change the calculation to take into account ref clock values also.
151	 */
152
153	WREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_FS_SPKLEN, 2);
154	WREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_SS_SCL_HCNT, 120);
155	WREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_SS_SCL_LCNT, 130);
156	WREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_SDA_HOLD, 20);
157}
158
159static void smu_v11_0_i2c_set_address(struct i2c_adapter *control, u16 address)
160{
161	struct amdgpu_smu_i2c_bus *smu_i2c = i2c_get_adapdata(control);
162	struct amdgpu_device *adev = smu_i2c->adev;
163
164	/* The IC_TAR::IC_TAR field is 10-bits wide.
165	 * It takes a 7-bit or 10-bit addresses as an address,
166	 * i.e. no read/write bit--no wire format, just the address.
167	 */
168	WREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_TAR, address & 0x3FF);
169}
170
171static uint32_t smu_v11_0_i2c_poll_tx_status(struct i2c_adapter *control)
172{
173	struct amdgpu_smu_i2c_bus *smu_i2c = i2c_get_adapdata(control);
174	struct amdgpu_device *adev = smu_i2c->adev;
175	uint32_t ret = I2C_OK;
176	uint32_t reg, reg_c_tx_abrt_source;
177
178	/*Check if transmission is completed */
179	unsigned long  timeout_counter = jiffies + msecs_to_jiffies(20);
180
181	do {
182		if (time_after(jiffies, timeout_counter)) {
183			ret |= I2C_SW_TIMEOUT;
184			break;
185		}
186
187		reg = RREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_STATUS);
188
189	} while (REG_GET_FIELD(reg, CKSVII2C_IC_STATUS, TFE) == 0);
190
191	if (ret != I2C_OK)
192		return ret;
193
194	/* This only checks if NAK is received and transaction got aborted */
195	reg = RREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_INTR_STAT);
196
197	if (REG_GET_FIELD(reg, CKSVII2C_IC_INTR_STAT, R_TX_ABRT) == 1) {
198		reg_c_tx_abrt_source = RREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_TX_ABRT_SOURCE);
199		DRM_INFO("TX was terminated, IC_TX_ABRT_SOURCE val is:%x", reg_c_tx_abrt_source);
200
201		/* Check for stop due to NACK */
202		if (REG_GET_FIELD(reg_c_tx_abrt_source,
203				  CKSVII2C_IC_TX_ABRT_SOURCE,
204				  ABRT_TXDATA_NOACK) == 1) {
205
206			ret |= I2C_NAK_TXDATA_NOACK;
207
208		} else if (REG_GET_FIELD(reg_c_tx_abrt_source,
209					 CKSVII2C_IC_TX_ABRT_SOURCE,
210					 ABRT_7B_ADDR_NOACK) == 1) {
211
212			ret |= I2C_NAK_7B_ADDR_NOACK;
213		} else {
214			ret |= I2C_ABORT;
215		}
216
217		smu_v11_0_i2c_clear_status(control);
218	}
219
220	return ret;
221}
222
223static uint32_t smu_v11_0_i2c_poll_rx_status(struct i2c_adapter *control)
224{
225	struct amdgpu_smu_i2c_bus *smu_i2c = i2c_get_adapdata(control);
226	struct amdgpu_device *adev = smu_i2c->adev;
227	uint32_t ret = I2C_OK;
228	uint32_t reg_ic_status, reg_c_tx_abrt_source;
229
230	reg_c_tx_abrt_source = RREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_TX_ABRT_SOURCE);
231
232	/* If slave is not present */
233	if (REG_GET_FIELD(reg_c_tx_abrt_source,
234			  CKSVII2C_IC_TX_ABRT_SOURCE,
235			  ABRT_7B_ADDR_NOACK) == 1) {
236		ret |= I2C_NAK_7B_ADDR_NOACK;
237
238		smu_v11_0_i2c_clear_status(control);
239	} else {  /* wait till some data is there in RXFIFO */
240		/* Poll for some byte in RXFIFO */
241		unsigned long  timeout_counter = jiffies + msecs_to_jiffies(20);
242
243		do {
244			if (time_after(jiffies, timeout_counter)) {
245				ret |= I2C_SW_TIMEOUT;
246				break;
247			}
248
249			reg_ic_status = RREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_STATUS);
250
251		} while (REG_GET_FIELD(reg_ic_status, CKSVII2C_IC_STATUS, RFNE) == 0);
252	}
253
254	return ret;
255}
256
257/**
258 * smu_v11_0_i2c_transmit - Send a block of data over the I2C bus to a slave device.
259 *
260 * @control: I2C adapter reference
261 * @address: The I2C address of the slave device.
262 * @data: The data to transmit over the bus.
263 * @numbytes: The amount of data to transmit.
264 * @i2c_flag: Flags for transmission
265 *
266 * Returns 0 on success or error.
267 */
268static uint32_t smu_v11_0_i2c_transmit(struct i2c_adapter *control,
269				       u16 address, u8 *data,
270				       u32 numbytes, u32 i2c_flag)
271{
272	struct amdgpu_smu_i2c_bus *smu_i2c = i2c_get_adapdata(control);
273	struct amdgpu_device *adev = smu_i2c->adev;
274	u32 bytes_sent, reg, ret = I2C_OK;
275	unsigned long  timeout_counter;
276
277	bytes_sent = 0;
278
279	DRM_DEBUG_DRIVER("I2C_Transmit(), address = %x, bytes = %d , data: ",
280			 address, numbytes);
281
282	if (drm_debug_enabled(DRM_UT_DRIVER)) {
283		print_hex_dump(KERN_INFO, "data: ", DUMP_PREFIX_NONE,
284			       16, 1, data, numbytes, false);
285	}
286
287	/* Set the I2C slave address */
288	smu_v11_0_i2c_set_address(control, address);
289	/* Enable I2C */
290	smu_v11_0_i2c_enable(control, true);
291
292	/* Clear status bits */
293	smu_v11_0_i2c_clear_status(control);
294
295	timeout_counter = jiffies + msecs_to_jiffies(20);
296
297	while (numbytes > 0) {
298		reg = RREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_STATUS);
299		if (!REG_GET_FIELD(reg, CKSVII2C_IC_STATUS, TFNF)) {
300			/*
301			 * We waited for too long for the transmission
302			 * FIFO to become not-full.  Exit the loop
303			 * with error.
304			 */
305			if (time_after(jiffies, timeout_counter)) {
306				ret |= I2C_SW_TIMEOUT;
307				goto Err;
308			}
309		} else {
310			reg = REG_SET_FIELD(reg, CKSVII2C_IC_DATA_CMD, DAT,
311					    data[bytes_sent]);
312
313			/* Final message, final byte, must generate a
314			 * STOP to release the bus, i.e. don't hold
315			 * SCL low.
316			 */
317			if (numbytes == 1 && i2c_flag & I2C_M_STOP)
318				reg = REG_SET_FIELD(reg,
319						    CKSVII2C_IC_DATA_CMD,
320						    STOP, 1);
321
322			if (bytes_sent == 0 && i2c_flag & I2C_X_RESTART)
323				reg = REG_SET_FIELD(reg,
324						    CKSVII2C_IC_DATA_CMD,
325						    RESTART, 1);
326
327			/* Write */
328			reg = REG_SET_FIELD(reg, CKSVII2C_IC_DATA_CMD, CMD, 0);
329			WREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_DATA_CMD, reg);
330
331			/* Record that the bytes were transmitted */
332			bytes_sent++;
333			numbytes--;
334		}
335	}
336
337	ret = smu_v11_0_i2c_poll_tx_status(control);
338Err:
339	/* Any error, no point in proceeding */
340	if (ret != I2C_OK) {
341		if (ret & I2C_SW_TIMEOUT)
342			DRM_ERROR("TIMEOUT ERROR !!!");
343
344		if (ret & I2C_NAK_7B_ADDR_NOACK)
345			DRM_ERROR("Received I2C_NAK_7B_ADDR_NOACK !!!");
346
347
348		if (ret & I2C_NAK_TXDATA_NOACK)
349			DRM_ERROR("Received I2C_NAK_TXDATA_NOACK !!!");
350	}
351
352	return ret;
353}
354
355
356/**
357 * smu_v11_0_i2c_receive - Receive a block of data over the I2C bus from a slave device.
358 *
359 * @control: I2C adapter reference
360 * @address: The I2C address of the slave device.
361 * @data: Placeholder to store received data.
362 * @numbytes: The amount of data to transmit.
363 * @i2c_flag: Flags for transmission
364 *
365 * Returns 0 on success or error.
366 */
367static uint32_t smu_v11_0_i2c_receive(struct i2c_adapter *control,
368				      u16 address, u8 *data,
369				      u32 numbytes, u32 i2c_flag)
370{
371	struct amdgpu_smu_i2c_bus *smu_i2c = i2c_get_adapdata(control);
372	struct amdgpu_device *adev = smu_i2c->adev;
373	uint32_t bytes_received, ret = I2C_OK;
374
375	bytes_received = 0;
376
377	/* Set the I2C slave address */
378	smu_v11_0_i2c_set_address(control, address);
379
380	/* Enable I2C */
381	smu_v11_0_i2c_enable(control, true);
382
383	while (numbytes > 0) {
384		uint32_t reg = 0;
385
386		smu_v11_0_i2c_clear_status(control);
387
388		/* Prepare transaction */
389		reg = REG_SET_FIELD(reg, CKSVII2C_IC_DATA_CMD, DAT, 0);
390		/* Read */
391		reg = REG_SET_FIELD(reg, CKSVII2C_IC_DATA_CMD, CMD, 1);
392
393		/* Final message, final byte, must generate a STOP
394		 * to release the bus, i.e. don't hold SCL low.
395		 */
396		if (numbytes == 1 && i2c_flag & I2C_M_STOP)
397			reg = REG_SET_FIELD(reg, CKSVII2C_IC_DATA_CMD,
398					    STOP, 1);
399
400		if (bytes_received == 0 && i2c_flag & I2C_X_RESTART)
401			reg = REG_SET_FIELD(reg, CKSVII2C_IC_DATA_CMD,
402					    RESTART, 1);
403
404		WREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_DATA_CMD, reg);
405
406		ret = smu_v11_0_i2c_poll_rx_status(control);
407
408		/* Any error, no point in proceeding */
409		if (ret != I2C_OK) {
410			if (ret & I2C_SW_TIMEOUT)
411				DRM_ERROR("TIMEOUT ERROR !!!");
412
413			if (ret & I2C_NAK_7B_ADDR_NOACK)
414				DRM_ERROR("Received I2C_NAK_7B_ADDR_NOACK !!!");
415
416			if (ret & I2C_NAK_TXDATA_NOACK)
417				DRM_ERROR("Received I2C_NAK_TXDATA_NOACK !!!");
418
419			break;
420		}
421
422		reg = RREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_DATA_CMD);
423		data[bytes_received] = REG_GET_FIELD(reg, CKSVII2C_IC_DATA_CMD, DAT);
424
425		/* Record that the bytes were received */
426		bytes_received++;
427		numbytes--;
428	}
429
430	DRM_DEBUG_DRIVER("I2C_Receive(), address = %x, bytes = %d, data :",
431		  (uint16_t)address, bytes_received);
432
433	if (drm_debug_enabled(DRM_UT_DRIVER)) {
434		print_hex_dump(KERN_INFO, "data: ", DUMP_PREFIX_NONE,
435			       16, 1, data, bytes_received, false);
436	}
437
438	return ret;
439}
440
441static void smu_v11_0_i2c_abort(struct i2c_adapter *control)
442{
443	struct amdgpu_smu_i2c_bus *smu_i2c = i2c_get_adapdata(control);
444	struct amdgpu_device *adev = smu_i2c->adev;
445	uint32_t reg = 0;
446
447	/* Enable I2C engine; */
448	reg = REG_SET_FIELD(reg, CKSVII2C_IC_ENABLE, ENABLE, 1);
449	WREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_ENABLE, reg);
450
451	/* Abort previous transaction */
452	reg = REG_SET_FIELD(reg, CKSVII2C_IC_ENABLE, ABORT, 1);
453	WREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_ENABLE, reg);
454
455	DRM_DEBUG_DRIVER("I2C_Abort() Done.");
456}
457
458static bool smu_v11_0_i2c_activity_done(struct i2c_adapter *control)
459{
460	struct amdgpu_smu_i2c_bus *smu_i2c = i2c_get_adapdata(control);
461	struct amdgpu_device *adev = smu_i2c->adev;
462
463	const uint32_t IDLE_TIMEOUT = 1024;
464	uint32_t timeout_count = 0;
465	uint32_t reg_ic_enable, reg_ic_enable_status, reg_ic_clr_activity;
466
467	reg_ic_enable_status = RREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_ENABLE_STATUS);
468	reg_ic_enable = RREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_ENABLE);
469
470	if ((REG_GET_FIELD(reg_ic_enable, CKSVII2C_IC_ENABLE, ENABLE) == 0) &&
471	    (REG_GET_FIELD(reg_ic_enable_status, CKSVII2C_IC_ENABLE_STATUS, IC_EN) == 1)) {
472		/*
473		 * Nobody is using I2C engine, but engine remains active because
474		 * someone missed to send STOP
475		 */
476		smu_v11_0_i2c_abort(control);
477	} else if (REG_GET_FIELD(reg_ic_enable, CKSVII2C_IC_ENABLE, ENABLE) == 0) {
478		/* Nobody is using I2C engine */
479		return true;
480	}
481
482	/* Keep reading activity bit until it's cleared */
483	do {
484		reg_ic_clr_activity = RREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_CLR_ACTIVITY);
485
486		if (REG_GET_FIELD(reg_ic_clr_activity,
487		    CKSVII2C_IC_CLR_ACTIVITY, CLR_ACTIVITY) == 0)
488			return true;
489
490		++timeout_count;
491
492	} while (timeout_count < IDLE_TIMEOUT);
493
494	return false;
495}
496
497static void smu_v11_0_i2c_init(struct i2c_adapter *control)
498{
499	int res;
500
501	/* Disable clock gating */
502	smu_v11_0_i2c_set_clock_gating(control, false);
503
504	if (!smu_v11_0_i2c_activity_done(control))
505		DRM_WARN("I2C busy !");
506
507	/* Disable I2C */
508	res = smu_v11_0_i2c_enable(control, false);
509	if (res != I2C_OK)
510		smu_v11_0_i2c_abort(control);
511
512	/* Configure I2C to operate as master and in standard mode */
513	smu_v11_0_i2c_configure(control);
514
515	/* Initialize the clock to 50 kHz default */
516	smu_v11_0_i2c_set_clock(control);
517
518}
519
520static void smu_v11_0_i2c_fini(struct i2c_adapter *control)
521{
522	struct amdgpu_smu_i2c_bus *smu_i2c = i2c_get_adapdata(control);
523	struct amdgpu_device *adev = smu_i2c->adev;
524	u32 status, enable, en_stat;
525	int res;
526
527	res = smu_v11_0_i2c_enable(control, false);
528	if (res != I2C_OK) {
529		status  = RREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_STATUS);
530		enable  = RREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_ENABLE);
531		en_stat = RREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_ENABLE_STATUS);
532
533		/* Nobody is using the I2C engine, yet it remains
534		 * active, possibly because someone missed to send
535		 * STOP.
536		 */
537		DRM_DEBUG_DRIVER("Aborting from fini: status:0x%08x "
538				 "enable:0x%08x enable_stat:0x%08x",
539				 status, enable, en_stat);
540		smu_v11_0_i2c_abort(control);
541	}
542
543	/* Restore clock gating */
544
545	/*
546	 * TODO Reenabling clock gating seems to break subsequent SMU operation
547	 *      on the I2C bus. My guess is that SMU doesn't disable clock gating like
548	 *      we do here before working with the bus. So for now just don't restore
549	 *      it but later work with SMU to see if they have this issue and can
550	 *      update their code appropriately
551	 */
552	/* smu_v11_0_i2c_set_clock_gating(control, true); */
553
554}
555
556static bool smu_v11_0_i2c_bus_lock(struct i2c_adapter *control)
557{
558	struct amdgpu_smu_i2c_bus *smu_i2c = i2c_get_adapdata(control);
559	struct amdgpu_device *adev = smu_i2c->adev;
560
561	/* Send  PPSMC_MSG_RequestI2CBus */
562	if (!amdgpu_dpm_smu_i2c_bus_access(adev, true))
563		return true;
564
565	return false;
566}
567
568static bool smu_v11_0_i2c_bus_unlock(struct i2c_adapter *control)
569{
570	struct amdgpu_smu_i2c_bus *smu_i2c = i2c_get_adapdata(control);
571	struct amdgpu_device *adev = smu_i2c->adev;
572
573	/* Send  PPSMC_MSG_ReleaseI2CBus */
574	if (!amdgpu_dpm_smu_i2c_bus_access(adev, false))
575		return true;
576
577	return false;
578}
579
580/***************************** I2C GLUE ****************************/
581
582static uint32_t smu_v11_0_i2c_read_data(struct i2c_adapter *control,
583					struct i2c_msg *msg, uint32_t i2c_flag)
584{
585	uint32_t  ret;
586
587	ret = smu_v11_0_i2c_receive(control, msg->addr, msg->buf, msg->len, i2c_flag);
588
589	if (ret != I2C_OK)
590		DRM_ERROR("ReadData() - I2C error occurred :%x", ret);
591
592	return ret;
593}
594
595static uint32_t smu_v11_0_i2c_write_data(struct i2c_adapter *control,
596					struct i2c_msg *msg, uint32_t i2c_flag)
597{
598	uint32_t  ret;
599
600	ret = smu_v11_0_i2c_transmit(control, msg->addr, msg->buf, msg->len, i2c_flag);
601
602	if (ret != I2C_OK)
603		DRM_ERROR("WriteI2CData() - I2C error occurred :%x", ret);
604
605	return ret;
606
607}
608
609static void lock_bus(struct i2c_adapter *i2c, unsigned int flags)
610{
611	struct amdgpu_smu_i2c_bus *smu_i2c = i2c_get_adapdata(i2c);
612	struct amdgpu_device *adev = smu_i2c->adev;
613
614	mutex_lock(&smu_i2c->mutex);
615	if (!smu_v11_0_i2c_bus_lock(i2c))
616		DRM_ERROR("Failed to lock the bus from SMU");
617	else
618		adev->pm.bus_locked = true;
619}
620
621static int trylock_bus(struct i2c_adapter *i2c, unsigned int flags)
622{
623	WARN_ONCE(1, "This operation not supposed to run in atomic context!");
624	return false;
625}
626
627static void unlock_bus(struct i2c_adapter *i2c, unsigned int flags)
628{
629	struct amdgpu_smu_i2c_bus *smu_i2c = i2c_get_adapdata(i2c);
630	struct amdgpu_device *adev = smu_i2c->adev;
631
632	if (!smu_v11_0_i2c_bus_unlock(i2c))
633		DRM_ERROR("Failed to unlock the bus from SMU");
634	else
635		adev->pm.bus_locked = false;
636	mutex_unlock(&smu_i2c->mutex);
637}
638
639static const struct i2c_lock_operations smu_v11_0_i2c_i2c_lock_ops = {
640	.lock_bus = lock_bus,
641	.trylock_bus = trylock_bus,
642	.unlock_bus = unlock_bus,
643};
644
645static int smu_v11_0_i2c_xfer(struct i2c_adapter *i2c_adap,
646			      struct i2c_msg *msg, int num)
647{
648	int i, ret;
649	u16 addr, dir;
650
651	smu_v11_0_i2c_init(i2c_adap);
652
653	/* From the client's point of view, this sequence of
654	 * messages-- the array i2c_msg *msg, is a single transaction
655	 * on the bus, starting with START and ending with STOP.
656	 *
657	 * The client is welcome to send any sequence of messages in
658	 * this array, as processing under this function here is
659	 * striving to be agnostic.
660	 *
661	 * Record the first address and direction we see. If either
662	 * changes for a subsequent message, generate ReSTART. The
663	 * DW_apb_i2c databook, v1.21a, specifies that ReSTART is
664	 * generated when the direction changes, with the default IP
665	 * block parameter settings, but it doesn't specify if ReSTART
666	 * is generated when the address changes (possibly...). We
667	 * don't rely on the default IP block parameter settings as
668	 * the block is shared and they may change.
669	 */
670	if (num > 0) {
671		addr = msg[0].addr;
672		dir  = msg[0].flags & I2C_M_RD;
673	}
674
675	for (i = 0; i < num; i++) {
676		u32 i2c_flag = 0;
677
678		if (msg[i].addr != addr || (msg[i].flags ^ dir) & I2C_M_RD) {
679			addr = msg[i].addr;
680			dir  = msg[i].flags & I2C_M_RD;
681			i2c_flag |= I2C_X_RESTART;
682		}
683
684		if (i == num - 1) {
685			/* Set the STOP bit on the last message, so
686			 * that the IP block generates a STOP after
687			 * the last byte of the message.
688			 */
689			i2c_flag |= I2C_M_STOP;
690		}
691
692		if (msg[i].flags & I2C_M_RD)
693			ret = smu_v11_0_i2c_read_data(i2c_adap,
694						      msg + i,
695						      i2c_flag);
696		else
697			ret = smu_v11_0_i2c_write_data(i2c_adap,
698						       msg + i,
699						       i2c_flag);
700
701		if (ret != I2C_OK) {
702			num = -EIO;
703			break;
704		}
705	}
706
707	smu_v11_0_i2c_fini(i2c_adap);
708	return num;
709}
710
711static u32 smu_v11_0_i2c_func(struct i2c_adapter *adap)
712{
713	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
714}
715
716static const struct i2c_algorithm smu_v11_0_i2c_algo = {
717	.master_xfer = smu_v11_0_i2c_xfer,
718	.functionality = smu_v11_0_i2c_func,
719};
720
721static const struct i2c_adapter_quirks smu_v11_0_i2c_control_quirks = {
722	.flags = I2C_AQ_NO_ZERO_LEN,
723};
724
725int smu_v11_0_i2c_control_init(struct amdgpu_device *adev)
726{
727	struct amdgpu_smu_i2c_bus *smu_i2c = &adev->pm.smu_i2c[0];
728	struct i2c_adapter *control = &smu_i2c->adapter;
729	int res;
730
731	smu_i2c->adev = adev;
732	smu_i2c->port = 0;
733	mutex_init(&smu_i2c->mutex);
734	control->owner = THIS_MODULE;
735	control->class = I2C_CLASS_HWMON;
736	control->dev.parent = &adev->pdev->dev;
737	control->algo = &smu_v11_0_i2c_algo;
738	snprintf(control->name, sizeof(control->name), "AMDGPU SMU 0");
739	control->lock_ops = &smu_v11_0_i2c_i2c_lock_ops;
740	control->quirks = &smu_v11_0_i2c_control_quirks;
741	i2c_set_adapdata(control, smu_i2c);
742
743	adev->pm.ras_eeprom_i2c_bus = &adev->pm.smu_i2c[0].adapter;
744	adev->pm.fru_eeprom_i2c_bus = &adev->pm.smu_i2c[0].adapter;
745
746	res = i2c_add_adapter(control);
747	if (res)
748		DRM_ERROR("Failed to register hw i2c, err: %d\n", res);
749
750	return res;
751}
752
753void smu_v11_0_i2c_control_fini(struct amdgpu_device *adev)
754{
755	struct i2c_adapter *control = adev->pm.ras_eeprom_i2c_bus;
756
757	i2c_del_adapter(control);
758	adev->pm.ras_eeprom_i2c_bus = NULL;
759	adev->pm.fru_eeprom_i2c_bus = NULL;
760}
761
762/*
763 * Keep this for future unit test if bugs arise
764 */
765#if 0
766#define I2C_TARGET_ADDR 0xA0
767
768bool smu_v11_0_i2c_test_bus(struct i2c_adapter *control)
769{
770
771	uint32_t ret = I2C_OK;
772	uint8_t data[6] = {0xf, 0, 0xde, 0xad, 0xbe, 0xef};
773
774
775	DRM_INFO("Begin");
776
777	if (!smu_v11_0_i2c_bus_lock(control)) {
778		DRM_ERROR("Failed to lock the bus!.");
779		return false;
780	}
781
782	smu_v11_0_i2c_init(control);
783
784	/* Write 0xde to address 0x0000 on the EEPROM */
785	ret = smu_v11_0_i2c_write_data(control, I2C_TARGET_ADDR, data, 6);
786
787	ret = smu_v11_0_i2c_read_data(control, I2C_TARGET_ADDR, data, 6);
788
789	smu_v11_0_i2c_fini(control);
790
791	smu_v11_0_i2c_bus_unlock(control);
792
793
794	DRM_INFO("End");
795	return true;
796}
797#endif
798