xref: /openbmc/linux/drivers/soc/qcom/qcom-geni-se.c (revision dfc53baa)
1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (c) 2017-2018, The Linux Foundation. All rights reserved.
3 
4 #include <linux/acpi.h>
5 #include <linux/clk.h>
6 #include <linux/console.h>
7 #include <linux/slab.h>
8 #include <linux/dma-mapping.h>
9 #include <linux/io.h>
10 #include <linux/module.h>
11 #include <linux/of.h>
12 #include <linux/of_platform.h>
13 #include <linux/pinctrl/consumer.h>
14 #include <linux/platform_device.h>
15 #include <linux/qcom-geni-se.h>
16 
17 /**
18  * DOC: Overview
19  *
20  * Generic Interface (GENI) Serial Engine (SE) Wrapper driver is introduced
21  * to manage GENI firmware based Qualcomm Universal Peripheral (QUP) Wrapper
22  * controller. QUP Wrapper is designed to support various serial bus protocols
23  * like UART, SPI, I2C, I3C, etc.
24  */
25 
26 /**
27  * DOC: Hardware description
28  *
29  * GENI based QUP is a highly-flexible and programmable module for supporting
30  * a wide range of serial interfaces like UART, SPI, I2C, I3C, etc. A single
31  * QUP module can provide upto 8 serial interfaces, using its internal
32  * serial engines. The actual configuration is determined by the target
33  * platform configuration. The protocol supported by each interface is
34  * determined by the firmware loaded to the serial engine. Each SE consists
35  * of a DMA Engine and GENI sub modules which enable serial engines to
36  * support FIFO and DMA modes of operation.
37  *
38  *
39  *                      +-----------------------------------------+
40  *                      |QUP Wrapper                              |
41  *                      |         +----------------------------+  |
42  *   --QUP & SE Clocks-->         | Serial Engine N            |  +-IO------>
43  *                      |         | ...                        |  | Interface
44  *   <---Clock Perf.----+    +----+-----------------------+    |  |
45  *     State Interface  |    | Serial Engine 1            |    |  |
46  *                      |    |                            |    |  |
47  *                      |    |                            |    |  |
48  *   <--------AHB------->    |                            |    |  |
49  *                      |    |                            +----+  |
50  *                      |    |                            |       |
51  *                      |    |                            |       |
52  *   <------SE IRQ------+    +----------------------------+       |
53  *                      |                                         |
54  *                      +-----------------------------------------+
55  *
56  *                         Figure 1: GENI based QUP Wrapper
57  *
58  * The GENI submodules include primary and secondary sequencers which are
59  * used to drive TX & RX operations. On serial interfaces that operate using
60  * master-slave model, primary sequencer drives both TX & RX operations. On
61  * serial interfaces that operate using peer-to-peer model, primary sequencer
62  * drives TX operation and secondary sequencer drives RX operation.
63  */
64 
65 /**
66  * DOC: Software description
67  *
68  * GENI SE Wrapper driver is structured into 2 parts:
69  *
70  * geni_wrapper represents QUP Wrapper controller. This part of the driver
71  * manages QUP Wrapper information such as hardware version, clock
72  * performance table that is common to all the internal serial engines.
73  *
74  * geni_se represents serial engine. This part of the driver manages serial
75  * engine information such as clocks, containing QUP Wrapper, etc. This part
76  * of driver also supports operations (eg. initialize the concerned serial
77  * engine, select between FIFO and DMA mode of operation etc.) that are
78  * common to all the serial engines and are independent of serial interfaces.
79  */
80 
81 #define MAX_CLK_PERF_LEVEL 32
82 #define NUM_AHB_CLKS 2
83 
84 /**
85  * @struct geni_wrapper - Data structure to represent the QUP Wrapper Core
86  * @dev:		Device pointer of the QUP wrapper core
87  * @base:		Base address of this instance of QUP wrapper core
88  * @ahb_clks:		Handle to the primary & secondary AHB clocks
89  */
90 struct geni_wrapper {
91 	struct device *dev;
92 	void __iomem *base;
93 	struct clk_bulk_data ahb_clks[NUM_AHB_CLKS];
94 	struct geni_icc_path to_core;
95 };
96 
97 static const char * const icc_path_names[] = {"qup-core", "qup-config",
98 						"qup-memory"};
99 
100 static struct geni_wrapper *earlycon_wrapper;
101 
102 #define QUP_HW_VER_REG			0x4
103 
104 /* Common SE registers */
105 #define GENI_INIT_CFG_REVISION		0x0
106 #define GENI_S_INIT_CFG_REVISION	0x4
107 #define GENI_OUTPUT_CTRL		0x24
108 #define GENI_CGC_CTRL			0x28
109 #define GENI_CLK_CTRL_RO		0x60
110 #define GENI_IF_DISABLE_RO		0x64
111 #define GENI_FW_S_REVISION_RO		0x6c
112 #define SE_GENI_BYTE_GRAN		0x254
113 #define SE_GENI_TX_PACKING_CFG0		0x260
114 #define SE_GENI_TX_PACKING_CFG1		0x264
115 #define SE_GENI_RX_PACKING_CFG0		0x284
116 #define SE_GENI_RX_PACKING_CFG1		0x288
117 #define SE_GENI_M_GP_LENGTH		0x910
118 #define SE_GENI_S_GP_LENGTH		0x914
119 #define SE_DMA_TX_PTR_L			0xc30
120 #define SE_DMA_TX_PTR_H			0xc34
121 #define SE_DMA_TX_ATTR			0xc38
122 #define SE_DMA_TX_LEN			0xc3c
123 #define SE_DMA_TX_IRQ_EN		0xc48
124 #define SE_DMA_TX_IRQ_EN_SET		0xc4c
125 #define SE_DMA_TX_IRQ_EN_CLR		0xc50
126 #define SE_DMA_TX_LEN_IN		0xc54
127 #define SE_DMA_TX_MAX_BURST		0xc5c
128 #define SE_DMA_RX_PTR_L			0xd30
129 #define SE_DMA_RX_PTR_H			0xd34
130 #define SE_DMA_RX_ATTR			0xd38
131 #define SE_DMA_RX_LEN			0xd3c
132 #define SE_DMA_RX_IRQ_EN		0xd48
133 #define SE_DMA_RX_IRQ_EN_SET		0xd4c
134 #define SE_DMA_RX_IRQ_EN_CLR		0xd50
135 #define SE_DMA_RX_LEN_IN		0xd54
136 #define SE_DMA_RX_MAX_BURST		0xd5c
137 #define SE_DMA_RX_FLUSH			0xd60
138 #define SE_GSI_EVENT_EN			0xe18
139 #define SE_IRQ_EN			0xe1c
140 #define SE_DMA_GENERAL_CFG		0xe30
141 
142 /* GENI_OUTPUT_CTRL fields */
143 #define DEFAULT_IO_OUTPUT_CTRL_MSK	GENMASK(6, 0)
144 
145 /* GENI_CGC_CTRL fields */
146 #define CFG_AHB_CLK_CGC_ON		BIT(0)
147 #define CFG_AHB_WR_ACLK_CGC_ON		BIT(1)
148 #define DATA_AHB_CLK_CGC_ON		BIT(2)
149 #define SCLK_CGC_ON			BIT(3)
150 #define TX_CLK_CGC_ON			BIT(4)
151 #define RX_CLK_CGC_ON			BIT(5)
152 #define EXT_CLK_CGC_ON			BIT(6)
153 #define PROG_RAM_HCLK_OFF		BIT(8)
154 #define PROG_RAM_SCLK_OFF		BIT(9)
155 #define DEFAULT_CGC_EN			GENMASK(6, 0)
156 
157 /* SE_GSI_EVENT_EN fields */
158 #define DMA_RX_EVENT_EN			BIT(0)
159 #define DMA_TX_EVENT_EN			BIT(1)
160 #define GENI_M_EVENT_EN			BIT(2)
161 #define GENI_S_EVENT_EN			BIT(3)
162 
163 /* SE_IRQ_EN fields */
164 #define DMA_RX_IRQ_EN			BIT(0)
165 #define DMA_TX_IRQ_EN			BIT(1)
166 #define GENI_M_IRQ_EN			BIT(2)
167 #define GENI_S_IRQ_EN			BIT(3)
168 
169 /* SE_DMA_GENERAL_CFG */
170 #define DMA_RX_CLK_CGC_ON		BIT(0)
171 #define DMA_TX_CLK_CGC_ON		BIT(1)
172 #define DMA_AHB_SLV_CFG_ON		BIT(2)
173 #define AHB_SEC_SLV_CLK_CGC_ON		BIT(3)
174 #define DUMMY_RX_NON_BUFFERABLE		BIT(4)
175 #define RX_DMA_ZERO_PADDING_EN		BIT(5)
176 #define RX_DMA_IRQ_DELAY_MSK		GENMASK(8, 6)
177 #define RX_DMA_IRQ_DELAY_SHFT		6
178 
179 /**
180  * geni_se_get_qup_hw_version() - Read the QUP wrapper Hardware version
181  * @se:	Pointer to the corresponding serial engine.
182  *
183  * Return: Hardware Version of the wrapper.
184  */
185 u32 geni_se_get_qup_hw_version(struct geni_se *se)
186 {
187 	struct geni_wrapper *wrapper = se->wrapper;
188 
189 	return readl_relaxed(wrapper->base + QUP_HW_VER_REG);
190 }
191 EXPORT_SYMBOL(geni_se_get_qup_hw_version);
192 
193 static void geni_se_io_set_mode(void __iomem *base)
194 {
195 	u32 val;
196 
197 	val = readl_relaxed(base + SE_IRQ_EN);
198 	val |= GENI_M_IRQ_EN | GENI_S_IRQ_EN;
199 	val |= DMA_TX_IRQ_EN | DMA_RX_IRQ_EN;
200 	writel_relaxed(val, base + SE_IRQ_EN);
201 
202 	val = readl_relaxed(base + SE_GENI_DMA_MODE_EN);
203 	val &= ~GENI_DMA_MODE_EN;
204 	writel_relaxed(val, base + SE_GENI_DMA_MODE_EN);
205 
206 	writel_relaxed(0, base + SE_GSI_EVENT_EN);
207 }
208 
209 static void geni_se_io_init(void __iomem *base)
210 {
211 	u32 val;
212 
213 	val = readl_relaxed(base + GENI_CGC_CTRL);
214 	val |= DEFAULT_CGC_EN;
215 	writel_relaxed(val, base + GENI_CGC_CTRL);
216 
217 	val = readl_relaxed(base + SE_DMA_GENERAL_CFG);
218 	val |= AHB_SEC_SLV_CLK_CGC_ON | DMA_AHB_SLV_CFG_ON;
219 	val |= DMA_TX_CLK_CGC_ON | DMA_RX_CLK_CGC_ON;
220 	writel_relaxed(val, base + SE_DMA_GENERAL_CFG);
221 
222 	writel_relaxed(DEFAULT_IO_OUTPUT_CTRL_MSK, base + GENI_OUTPUT_CTRL);
223 	writel_relaxed(FORCE_DEFAULT, base + GENI_FORCE_DEFAULT_REG);
224 }
225 
226 static void geni_se_irq_clear(struct geni_se *se)
227 {
228 	writel_relaxed(0, se->base + SE_GSI_EVENT_EN);
229 	writel_relaxed(0xffffffff, se->base + SE_GENI_M_IRQ_CLEAR);
230 	writel_relaxed(0xffffffff, se->base + SE_GENI_S_IRQ_CLEAR);
231 	writel_relaxed(0xffffffff, se->base + SE_DMA_TX_IRQ_CLR);
232 	writel_relaxed(0xffffffff, se->base + SE_DMA_RX_IRQ_CLR);
233 	writel_relaxed(0xffffffff, se->base + SE_IRQ_EN);
234 }
235 
236 /**
237  * geni_se_init() - Initialize the GENI serial engine
238  * @se:		Pointer to the concerned serial engine.
239  * @rx_wm:	Receive watermark, in units of FIFO words.
240  * @rx_rfr_wm:	Ready-for-receive watermark, in units of FIFO words.
241  *
242  * This function is used to initialize the GENI serial engine, configure
243  * receive watermark and ready-for-receive watermarks.
244  */
245 void geni_se_init(struct geni_se *se, u32 rx_wm, u32 rx_rfr)
246 {
247 	u32 val;
248 
249 	geni_se_irq_clear(se);
250 	geni_se_io_init(se->base);
251 	geni_se_io_set_mode(se->base);
252 
253 	writel_relaxed(rx_wm, se->base + SE_GENI_RX_WATERMARK_REG);
254 	writel_relaxed(rx_rfr, se->base + SE_GENI_RX_RFR_WATERMARK_REG);
255 
256 	val = readl_relaxed(se->base + SE_GENI_M_IRQ_EN);
257 	val |= M_COMMON_GENI_M_IRQ_EN;
258 	writel_relaxed(val, se->base + SE_GENI_M_IRQ_EN);
259 
260 	val = readl_relaxed(se->base + SE_GENI_S_IRQ_EN);
261 	val |= S_COMMON_GENI_S_IRQ_EN;
262 	writel_relaxed(val, se->base + SE_GENI_S_IRQ_EN);
263 }
264 EXPORT_SYMBOL(geni_se_init);
265 
266 static void geni_se_select_fifo_mode(struct geni_se *se)
267 {
268 	u32 proto = geni_se_read_proto(se);
269 	u32 val;
270 
271 	geni_se_irq_clear(se);
272 
273 	val = readl_relaxed(se->base + SE_GENI_M_IRQ_EN);
274 	if (proto != GENI_SE_UART) {
275 		val |= M_CMD_DONE_EN | M_TX_FIFO_WATERMARK_EN;
276 		val |= M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN;
277 	}
278 	writel_relaxed(val, se->base + SE_GENI_M_IRQ_EN);
279 
280 	val = readl_relaxed(se->base + SE_GENI_S_IRQ_EN);
281 	if (proto != GENI_SE_UART)
282 		val |= S_CMD_DONE_EN;
283 	writel_relaxed(val, se->base + SE_GENI_S_IRQ_EN);
284 
285 	val = readl_relaxed(se->base + SE_GENI_DMA_MODE_EN);
286 	val &= ~GENI_DMA_MODE_EN;
287 	writel_relaxed(val, se->base + SE_GENI_DMA_MODE_EN);
288 }
289 
290 static void geni_se_select_dma_mode(struct geni_se *se)
291 {
292 	u32 val;
293 
294 	geni_se_irq_clear(se);
295 
296 	val = readl_relaxed(se->base + SE_GENI_DMA_MODE_EN);
297 	val |= GENI_DMA_MODE_EN;
298 	writel_relaxed(val, se->base + SE_GENI_DMA_MODE_EN);
299 }
300 
301 /**
302  * geni_se_select_mode() - Select the serial engine transfer mode
303  * @se:		Pointer to the concerned serial engine.
304  * @mode:	Transfer mode to be selected.
305  */
306 void geni_se_select_mode(struct geni_se *se, enum geni_se_xfer_mode mode)
307 {
308 	WARN_ON(mode != GENI_SE_FIFO && mode != GENI_SE_DMA);
309 
310 	switch (mode) {
311 	case GENI_SE_FIFO:
312 		geni_se_select_fifo_mode(se);
313 		break;
314 	case GENI_SE_DMA:
315 		geni_se_select_dma_mode(se);
316 		break;
317 	case GENI_SE_INVALID:
318 	default:
319 		break;
320 	}
321 }
322 EXPORT_SYMBOL(geni_se_select_mode);
323 
324 /**
325  * DOC: Overview
326  *
327  * GENI FIFO packing is highly configurable. TX/RX packing/unpacking consist
328  * of up to 4 operations, each operation represented by 4 configuration vectors
329  * of 10 bits programmed in GENI_TX_PACKING_CFG0 and GENI_TX_PACKING_CFG1 for
330  * TX FIFO and in GENI_RX_PACKING_CFG0 and GENI_RX_PACKING_CFG1 for RX FIFO.
331  * Refer to below examples for detailed bit-field description.
332  *
333  * Example 1: word_size = 7, packing_mode = 4 x 8, msb_to_lsb = 1
334  *
335  *        +-----------+-------+-------+-------+-------+
336  *        |           | vec_0 | vec_1 | vec_2 | vec_3 |
337  *        +-----------+-------+-------+-------+-------+
338  *        | start     | 0x6   | 0xe   | 0x16  | 0x1e  |
339  *        | direction | 1     | 1     | 1     | 1     |
340  *        | length    | 6     | 6     | 6     | 6     |
341  *        | stop      | 0     | 0     | 0     | 1     |
342  *        +-----------+-------+-------+-------+-------+
343  *
344  * Example 2: word_size = 15, packing_mode = 2 x 16, msb_to_lsb = 0
345  *
346  *        +-----------+-------+-------+-------+-------+
347  *        |           | vec_0 | vec_1 | vec_2 | vec_3 |
348  *        +-----------+-------+-------+-------+-------+
349  *        | start     | 0x0   | 0x8   | 0x10  | 0x18  |
350  *        | direction | 0     | 0     | 0     | 0     |
351  *        | length    | 7     | 6     | 7     | 6     |
352  *        | stop      | 0     | 0     | 0     | 1     |
353  *        +-----------+-------+-------+-------+-------+
354  *
355  * Example 3: word_size = 23, packing_mode = 1 x 32, msb_to_lsb = 1
356  *
357  *        +-----------+-------+-------+-------+-------+
358  *        |           | vec_0 | vec_1 | vec_2 | vec_3 |
359  *        +-----------+-------+-------+-------+-------+
360  *        | start     | 0x16  | 0xe   | 0x6   | 0x0   |
361  *        | direction | 1     | 1     | 1     | 1     |
362  *        | length    | 7     | 7     | 6     | 0     |
363  *        | stop      | 0     | 0     | 1     | 0     |
364  *        +-----------+-------+-------+-------+-------+
365  *
366  */
367 
368 #define NUM_PACKING_VECTORS 4
369 #define PACKING_START_SHIFT 5
370 #define PACKING_DIR_SHIFT 4
371 #define PACKING_LEN_SHIFT 1
372 #define PACKING_STOP_BIT BIT(0)
373 #define PACKING_VECTOR_SHIFT 10
374 /**
375  * geni_se_config_packing() - Packing configuration of the serial engine
376  * @se:		Pointer to the concerned serial engine
377  * @bpw:	Bits of data per transfer word.
378  * @pack_words:	Number of words per fifo element.
379  * @msb_to_lsb:	Transfer from MSB to LSB or vice-versa.
380  * @tx_cfg:	Flag to configure the TX Packing.
381  * @rx_cfg:	Flag to configure the RX Packing.
382  *
383  * This function is used to configure the packing rules for the current
384  * transfer.
385  */
386 void geni_se_config_packing(struct geni_se *se, int bpw, int pack_words,
387 			    bool msb_to_lsb, bool tx_cfg, bool rx_cfg)
388 {
389 	u32 cfg0, cfg1, cfg[NUM_PACKING_VECTORS] = {0};
390 	int len;
391 	int temp_bpw = bpw;
392 	int idx_start = msb_to_lsb ? bpw - 1 : 0;
393 	int idx = idx_start;
394 	int idx_delta = msb_to_lsb ? -BITS_PER_BYTE : BITS_PER_BYTE;
395 	int ceil_bpw = ALIGN(bpw, BITS_PER_BYTE);
396 	int iter = (ceil_bpw * pack_words) / BITS_PER_BYTE;
397 	int i;
398 
399 	if (iter <= 0 || iter > NUM_PACKING_VECTORS)
400 		return;
401 
402 	for (i = 0; i < iter; i++) {
403 		len = min_t(int, temp_bpw, BITS_PER_BYTE) - 1;
404 		cfg[i] = idx << PACKING_START_SHIFT;
405 		cfg[i] |= msb_to_lsb << PACKING_DIR_SHIFT;
406 		cfg[i] |= len << PACKING_LEN_SHIFT;
407 
408 		if (temp_bpw <= BITS_PER_BYTE) {
409 			idx = ((i + 1) * BITS_PER_BYTE) + idx_start;
410 			temp_bpw = bpw;
411 		} else {
412 			idx = idx + idx_delta;
413 			temp_bpw = temp_bpw - BITS_PER_BYTE;
414 		}
415 	}
416 	cfg[iter - 1] |= PACKING_STOP_BIT;
417 	cfg0 = cfg[0] | (cfg[1] << PACKING_VECTOR_SHIFT);
418 	cfg1 = cfg[2] | (cfg[3] << PACKING_VECTOR_SHIFT);
419 
420 	if (tx_cfg) {
421 		writel_relaxed(cfg0, se->base + SE_GENI_TX_PACKING_CFG0);
422 		writel_relaxed(cfg1, se->base + SE_GENI_TX_PACKING_CFG1);
423 	}
424 	if (rx_cfg) {
425 		writel_relaxed(cfg0, se->base + SE_GENI_RX_PACKING_CFG0);
426 		writel_relaxed(cfg1, se->base + SE_GENI_RX_PACKING_CFG1);
427 	}
428 
429 	/*
430 	 * Number of protocol words in each FIFO entry
431 	 * 0 - 4x8, four words in each entry, max word size of 8 bits
432 	 * 1 - 2x16, two words in each entry, max word size of 16 bits
433 	 * 2 - 1x32, one word in each entry, max word size of 32 bits
434 	 * 3 - undefined
435 	 */
436 	if (pack_words || bpw == 32)
437 		writel_relaxed(bpw / 16, se->base + SE_GENI_BYTE_GRAN);
438 }
439 EXPORT_SYMBOL(geni_se_config_packing);
440 
441 static void geni_se_clks_off(struct geni_se *se)
442 {
443 	struct geni_wrapper *wrapper = se->wrapper;
444 
445 	clk_disable_unprepare(se->clk);
446 	clk_bulk_disable_unprepare(ARRAY_SIZE(wrapper->ahb_clks),
447 						wrapper->ahb_clks);
448 }
449 
450 /**
451  * geni_se_resources_off() - Turn off resources associated with the serial
452  *                           engine
453  * @se:	Pointer to the concerned serial engine.
454  *
455  * Return: 0 on success, standard Linux error codes on failure/error.
456  */
457 int geni_se_resources_off(struct geni_se *se)
458 {
459 	int ret;
460 
461 	if (has_acpi_companion(se->dev))
462 		return 0;
463 
464 	ret = pinctrl_pm_select_sleep_state(se->dev);
465 	if (ret)
466 		return ret;
467 
468 	geni_se_clks_off(se);
469 	return 0;
470 }
471 EXPORT_SYMBOL(geni_se_resources_off);
472 
473 static int geni_se_clks_on(struct geni_se *se)
474 {
475 	int ret;
476 	struct geni_wrapper *wrapper = se->wrapper;
477 
478 	ret = clk_bulk_prepare_enable(ARRAY_SIZE(wrapper->ahb_clks),
479 						wrapper->ahb_clks);
480 	if (ret)
481 		return ret;
482 
483 	ret = clk_prepare_enable(se->clk);
484 	if (ret)
485 		clk_bulk_disable_unprepare(ARRAY_SIZE(wrapper->ahb_clks),
486 							wrapper->ahb_clks);
487 	return ret;
488 }
489 
490 /**
491  * geni_se_resources_on() - Turn on resources associated with the serial
492  *                          engine
493  * @se:	Pointer to the concerned serial engine.
494  *
495  * Return: 0 on success, standard Linux error codes on failure/error.
496  */
497 int geni_se_resources_on(struct geni_se *se)
498 {
499 	int ret;
500 
501 	if (has_acpi_companion(se->dev))
502 		return 0;
503 
504 	ret = geni_se_clks_on(se);
505 	if (ret)
506 		return ret;
507 
508 	ret = pinctrl_pm_select_default_state(se->dev);
509 	if (ret)
510 		geni_se_clks_off(se);
511 
512 	return ret;
513 }
514 EXPORT_SYMBOL(geni_se_resources_on);
515 
516 /**
517  * geni_se_clk_tbl_get() - Get the clock table to program DFS
518  * @se:		Pointer to the concerned serial engine.
519  * @tbl:	Table in which the output is returned.
520  *
521  * This function is called by the protocol drivers to determine the different
522  * clock frequencies supported by serial engine core clock. The protocol
523  * drivers use the output to determine the clock frequency index to be
524  * programmed into DFS.
525  *
526  * Return: number of valid performance levels in the table on success,
527  *	   standard Linux error codes on failure.
528  */
529 int geni_se_clk_tbl_get(struct geni_se *se, unsigned long **tbl)
530 {
531 	long freq = 0;
532 	int i;
533 
534 	if (se->clk_perf_tbl) {
535 		*tbl = se->clk_perf_tbl;
536 		return se->num_clk_levels;
537 	}
538 
539 	se->clk_perf_tbl = devm_kcalloc(se->dev, MAX_CLK_PERF_LEVEL,
540 					sizeof(*se->clk_perf_tbl),
541 					GFP_KERNEL);
542 	if (!se->clk_perf_tbl)
543 		return -ENOMEM;
544 
545 	for (i = 0; i < MAX_CLK_PERF_LEVEL; i++) {
546 		freq = clk_round_rate(se->clk, freq + 1);
547 		if (freq <= 0 || freq == se->clk_perf_tbl[i - 1])
548 			break;
549 		se->clk_perf_tbl[i] = freq;
550 	}
551 	se->num_clk_levels = i;
552 	*tbl = se->clk_perf_tbl;
553 	return se->num_clk_levels;
554 }
555 EXPORT_SYMBOL(geni_se_clk_tbl_get);
556 
557 /**
558  * geni_se_clk_freq_match() - Get the matching or closest SE clock frequency
559  * @se:		Pointer to the concerned serial engine.
560  * @req_freq:	Requested clock frequency.
561  * @index:	Index of the resultant frequency in the table.
562  * @res_freq:	Resultant frequency of the source clock.
563  * @exact:	Flag to indicate exact multiple requirement of the requested
564  *		frequency.
565  *
566  * This function is called by the protocol drivers to determine the best match
567  * of the requested frequency as provided by the serial engine clock in order
568  * to meet the performance requirements.
569  *
570  * If we return success:
571  * - if @exact is true  then @res_freq / <an_integer> == @req_freq
572  * - if @exact is false then @res_freq / <an_integer> <= @req_freq
573  *
574  * Return: 0 on success, standard Linux error codes on failure.
575  */
576 int geni_se_clk_freq_match(struct geni_se *se, unsigned long req_freq,
577 			   unsigned int *index, unsigned long *res_freq,
578 			   bool exact)
579 {
580 	unsigned long *tbl;
581 	int num_clk_levels;
582 	int i;
583 	unsigned long best_delta;
584 	unsigned long new_delta;
585 	unsigned int divider;
586 
587 	num_clk_levels = geni_se_clk_tbl_get(se, &tbl);
588 	if (num_clk_levels < 0)
589 		return num_clk_levels;
590 
591 	if (num_clk_levels == 0)
592 		return -EINVAL;
593 
594 	best_delta = ULONG_MAX;
595 	for (i = 0; i < num_clk_levels; i++) {
596 		divider = DIV_ROUND_UP(tbl[i], req_freq);
597 		new_delta = req_freq - tbl[i] / divider;
598 		if (new_delta < best_delta) {
599 			/* We have a new best! */
600 			*index = i;
601 			*res_freq = tbl[i];
602 
603 			/* If the new best is exact then we're done */
604 			if (new_delta == 0)
605 				return 0;
606 
607 			/* Record how close we got */
608 			best_delta = new_delta;
609 		}
610 	}
611 
612 	if (exact)
613 		return -EINVAL;
614 
615 	return 0;
616 }
617 EXPORT_SYMBOL(geni_se_clk_freq_match);
618 
619 #define GENI_SE_DMA_DONE_EN BIT(0)
620 #define GENI_SE_DMA_EOT_EN BIT(1)
621 #define GENI_SE_DMA_AHB_ERR_EN BIT(2)
622 #define GENI_SE_DMA_EOT_BUF BIT(0)
623 /**
624  * geni_se_tx_dma_prep() - Prepare the serial engine for TX DMA transfer
625  * @se:			Pointer to the concerned serial engine.
626  * @buf:		Pointer to the TX buffer.
627  * @len:		Length of the TX buffer.
628  * @iova:		Pointer to store the mapped DMA address.
629  *
630  * This function is used to prepare the buffers for DMA TX.
631  *
632  * Return: 0 on success, standard Linux error codes on failure.
633  */
634 int geni_se_tx_dma_prep(struct geni_se *se, void *buf, size_t len,
635 			dma_addr_t *iova)
636 {
637 	struct geni_wrapper *wrapper = se->wrapper;
638 	u32 val;
639 
640 	if (!wrapper)
641 		return -EINVAL;
642 
643 	*iova = dma_map_single(wrapper->dev, buf, len, DMA_TO_DEVICE);
644 	if (dma_mapping_error(wrapper->dev, *iova))
645 		return -EIO;
646 
647 	val = GENI_SE_DMA_DONE_EN;
648 	val |= GENI_SE_DMA_EOT_EN;
649 	val |= GENI_SE_DMA_AHB_ERR_EN;
650 	writel_relaxed(val, se->base + SE_DMA_TX_IRQ_EN_SET);
651 	writel_relaxed(lower_32_bits(*iova), se->base + SE_DMA_TX_PTR_L);
652 	writel_relaxed(upper_32_bits(*iova), se->base + SE_DMA_TX_PTR_H);
653 	writel_relaxed(GENI_SE_DMA_EOT_BUF, se->base + SE_DMA_TX_ATTR);
654 	writel_relaxed(len, se->base + SE_DMA_TX_LEN);
655 	return 0;
656 }
657 EXPORT_SYMBOL(geni_se_tx_dma_prep);
658 
659 /**
660  * geni_se_rx_dma_prep() - Prepare the serial engine for RX DMA transfer
661  * @se:			Pointer to the concerned serial engine.
662  * @buf:		Pointer to the RX buffer.
663  * @len:		Length of the RX buffer.
664  * @iova:		Pointer to store the mapped DMA address.
665  *
666  * This function is used to prepare the buffers for DMA RX.
667  *
668  * Return: 0 on success, standard Linux error codes on failure.
669  */
670 int geni_se_rx_dma_prep(struct geni_se *se, void *buf, size_t len,
671 			dma_addr_t *iova)
672 {
673 	struct geni_wrapper *wrapper = se->wrapper;
674 	u32 val;
675 
676 	if (!wrapper)
677 		return -EINVAL;
678 
679 	*iova = dma_map_single(wrapper->dev, buf, len, DMA_FROM_DEVICE);
680 	if (dma_mapping_error(wrapper->dev, *iova))
681 		return -EIO;
682 
683 	val = GENI_SE_DMA_DONE_EN;
684 	val |= GENI_SE_DMA_EOT_EN;
685 	val |= GENI_SE_DMA_AHB_ERR_EN;
686 	writel_relaxed(val, se->base + SE_DMA_RX_IRQ_EN_SET);
687 	writel_relaxed(lower_32_bits(*iova), se->base + SE_DMA_RX_PTR_L);
688 	writel_relaxed(upper_32_bits(*iova), se->base + SE_DMA_RX_PTR_H);
689 	/* RX does not have EOT buffer type bit. So just reset RX_ATTR */
690 	writel_relaxed(0, se->base + SE_DMA_RX_ATTR);
691 	writel_relaxed(len, se->base + SE_DMA_RX_LEN);
692 	return 0;
693 }
694 EXPORT_SYMBOL(geni_se_rx_dma_prep);
695 
696 /**
697  * geni_se_tx_dma_unprep() - Unprepare the serial engine after TX DMA transfer
698  * @se:			Pointer to the concerned serial engine.
699  * @iova:		DMA address of the TX buffer.
700  * @len:		Length of the TX buffer.
701  *
702  * This function is used to unprepare the DMA buffers after DMA TX.
703  */
704 void geni_se_tx_dma_unprep(struct geni_se *se, dma_addr_t iova, size_t len)
705 {
706 	struct geni_wrapper *wrapper = se->wrapper;
707 
708 	if (iova && !dma_mapping_error(wrapper->dev, iova))
709 		dma_unmap_single(wrapper->dev, iova, len, DMA_TO_DEVICE);
710 }
711 EXPORT_SYMBOL(geni_se_tx_dma_unprep);
712 
713 /**
714  * geni_se_rx_dma_unprep() - Unprepare the serial engine after RX DMA transfer
715  * @se:			Pointer to the concerned serial engine.
716  * @iova:		DMA address of the RX buffer.
717  * @len:		Length of the RX buffer.
718  *
719  * This function is used to unprepare the DMA buffers after DMA RX.
720  */
721 void geni_se_rx_dma_unprep(struct geni_se *se, dma_addr_t iova, size_t len)
722 {
723 	struct geni_wrapper *wrapper = se->wrapper;
724 
725 	if (iova && !dma_mapping_error(wrapper->dev, iova))
726 		dma_unmap_single(wrapper->dev, iova, len, DMA_FROM_DEVICE);
727 }
728 EXPORT_SYMBOL(geni_se_rx_dma_unprep);
729 
730 int geni_icc_get(struct geni_se *se, const char *icc_ddr)
731 {
732 	int i, err;
733 	const char *icc_names[] = {"qup-core", "qup-config", icc_ddr};
734 
735 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
736 		if (!icc_names[i])
737 			continue;
738 
739 		se->icc_paths[i].path = devm_of_icc_get(se->dev, icc_names[i]);
740 		if (IS_ERR(se->icc_paths[i].path))
741 			goto err;
742 	}
743 
744 	return 0;
745 
746 err:
747 	err = PTR_ERR(se->icc_paths[i].path);
748 	if (err != -EPROBE_DEFER)
749 		dev_err_ratelimited(se->dev, "Failed to get ICC path '%s': %d\n",
750 					icc_names[i], err);
751 	return err;
752 
753 }
754 EXPORT_SYMBOL(geni_icc_get);
755 
756 int geni_icc_set_bw(struct geni_se *se)
757 {
758 	int i, ret;
759 
760 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
761 		ret = icc_set_bw(se->icc_paths[i].path,
762 			se->icc_paths[i].avg_bw, se->icc_paths[i].avg_bw);
763 		if (ret) {
764 			dev_err_ratelimited(se->dev, "ICC BW voting failed on path '%s': %d\n",
765 					icc_path_names[i], ret);
766 			return ret;
767 		}
768 	}
769 
770 	return 0;
771 }
772 EXPORT_SYMBOL(geni_icc_set_bw);
773 
774 void geni_icc_set_tag(struct geni_se *se, u32 tag)
775 {
776 	int i;
777 
778 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++)
779 		icc_set_tag(se->icc_paths[i].path, tag);
780 }
781 EXPORT_SYMBOL(geni_icc_set_tag);
782 
783 /* To do: Replace this by icc_bulk_enable once it's implemented in ICC core */
784 int geni_icc_enable(struct geni_se *se)
785 {
786 	int i, ret;
787 
788 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
789 		ret = icc_enable(se->icc_paths[i].path);
790 		if (ret) {
791 			dev_err_ratelimited(se->dev, "ICC enable failed on path '%s': %d\n",
792 					icc_path_names[i], ret);
793 			return ret;
794 		}
795 	}
796 
797 	return 0;
798 }
799 EXPORT_SYMBOL(geni_icc_enable);
800 
801 int geni_icc_disable(struct geni_se *se)
802 {
803 	int i, ret;
804 
805 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
806 		ret = icc_disable(se->icc_paths[i].path);
807 		if (ret) {
808 			dev_err_ratelimited(se->dev, "ICC disable failed on path '%s': %d\n",
809 					icc_path_names[i], ret);
810 			return ret;
811 		}
812 	}
813 
814 	return 0;
815 }
816 EXPORT_SYMBOL(geni_icc_disable);
817 
818 void geni_remove_earlycon_icc_vote(void)
819 {
820 	struct platform_device *pdev;
821 	struct geni_wrapper *wrapper;
822 	struct device_node *parent;
823 	struct device_node *child;
824 
825 	if (!earlycon_wrapper)
826 		return;
827 
828 	wrapper = earlycon_wrapper;
829 	parent = of_get_next_parent(wrapper->dev->of_node);
830 	for_each_child_of_node(parent, child) {
831 		if (!of_device_is_compatible(child, "qcom,geni-se-qup"))
832 			continue;
833 
834 		pdev = of_find_device_by_node(child);
835 		if (!pdev)
836 			continue;
837 
838 		wrapper = platform_get_drvdata(pdev);
839 		icc_put(wrapper->to_core.path);
840 		wrapper->to_core.path = NULL;
841 
842 	}
843 	of_node_put(parent);
844 
845 	earlycon_wrapper = NULL;
846 }
847 EXPORT_SYMBOL(geni_remove_earlycon_icc_vote);
848 
849 static int geni_se_probe(struct platform_device *pdev)
850 {
851 	struct device *dev = &pdev->dev;
852 	struct resource *res;
853 	struct geni_wrapper *wrapper;
854 	struct console __maybe_unused *bcon;
855 	bool __maybe_unused has_earlycon = false;
856 	int ret;
857 
858 	wrapper = devm_kzalloc(dev, sizeof(*wrapper), GFP_KERNEL);
859 	if (!wrapper)
860 		return -ENOMEM;
861 
862 	wrapper->dev = dev;
863 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
864 	wrapper->base = devm_ioremap_resource(dev, res);
865 	if (IS_ERR(wrapper->base))
866 		return PTR_ERR(wrapper->base);
867 
868 	if (!has_acpi_companion(&pdev->dev)) {
869 		wrapper->ahb_clks[0].id = "m-ahb";
870 		wrapper->ahb_clks[1].id = "s-ahb";
871 		ret = devm_clk_bulk_get(dev, NUM_AHB_CLKS, wrapper->ahb_clks);
872 		if (ret) {
873 			dev_err(dev, "Err getting AHB clks %d\n", ret);
874 			return ret;
875 		}
876 	}
877 
878 #ifdef CONFIG_SERIAL_EARLYCON
879 	for_each_console(bcon) {
880 		if (!strcmp(bcon->name, "qcom_geni")) {
881 			has_earlycon = true;
882 			break;
883 		}
884 	}
885 	if (!has_earlycon)
886 		goto exit;
887 
888 	wrapper->to_core.path = devm_of_icc_get(dev, "qup-core");
889 	if (IS_ERR(wrapper->to_core.path))
890 		return PTR_ERR(wrapper->to_core.path);
891 	/*
892 	 * Put minmal BW request on core clocks on behalf of early console.
893 	 * The vote will be removed earlycon exit function.
894 	 *
895 	 * Note: We are putting vote on each QUP wrapper instead only to which
896 	 * earlycon is connected because QUP core clock of different wrapper
897 	 * share same voltage domain. If core1 is put to 0, then core2 will
898 	 * also run at 0, if not voted. Default ICC vote will be removed ASA
899 	 * we touch any of the core clock.
900 	 * core1 = core2 = max(core1, core2)
901 	 */
902 	ret = icc_set_bw(wrapper->to_core.path, GENI_DEFAULT_BW,
903 				GENI_DEFAULT_BW);
904 	if (ret) {
905 		dev_err(&pdev->dev, "%s: ICC BW voting failed for core: %d\n",
906 			__func__, ret);
907 		return ret;
908 	}
909 
910 	if (of_get_compatible_child(pdev->dev.of_node, "qcom,geni-debug-uart"))
911 		earlycon_wrapper = wrapper;
912 	of_node_put(pdev->dev.of_node);
913 exit:
914 #endif
915 	dev_set_drvdata(dev, wrapper);
916 	dev_dbg(dev, "GENI SE Driver probed\n");
917 	return devm_of_platform_populate(dev);
918 }
919 
920 static const struct of_device_id geni_se_dt_match[] = {
921 	{ .compatible = "qcom,geni-se-qup", },
922 	{}
923 };
924 MODULE_DEVICE_TABLE(of, geni_se_dt_match);
925 
926 static struct platform_driver geni_se_driver = {
927 	.driver = {
928 		.name = "geni_se_qup",
929 		.of_match_table = geni_se_dt_match,
930 	},
931 	.probe = geni_se_probe,
932 };
933 module_platform_driver(geni_se_driver);
934 
935 MODULE_DESCRIPTION("GENI Serial Engine Driver");
936 MODULE_LICENSE("GPL v2");
937