xref: /linux/drivers/soc/qcom/qcom-geni-se.c (revision a1c3be890440a1769ed6f822376a3e3ab0d42994)
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  * @to_core:		Core ICC path
90  */
91 struct geni_wrapper {
92 	struct device *dev;
93 	void __iomem *base;
94 	struct clk_bulk_data ahb_clks[NUM_AHB_CLKS];
95 	struct geni_icc_path to_core;
96 };
97 
98 static const char * const icc_path_names[] = {"qup-core", "qup-config",
99 						"qup-memory"};
100 
101 static struct geni_wrapper *earlycon_wrapper;
102 
103 #define QUP_HW_VER_REG			0x4
104 
105 /* Common SE registers */
106 #define GENI_INIT_CFG_REVISION		0x0
107 #define GENI_S_INIT_CFG_REVISION	0x4
108 #define GENI_OUTPUT_CTRL		0x24
109 #define GENI_CGC_CTRL			0x28
110 #define GENI_CLK_CTRL_RO		0x60
111 #define GENI_IF_DISABLE_RO		0x64
112 #define GENI_FW_S_REVISION_RO		0x6c
113 #define SE_GENI_BYTE_GRAN		0x254
114 #define SE_GENI_TX_PACKING_CFG0		0x260
115 #define SE_GENI_TX_PACKING_CFG1		0x264
116 #define SE_GENI_RX_PACKING_CFG0		0x284
117 #define SE_GENI_RX_PACKING_CFG1		0x288
118 #define SE_GENI_M_GP_LENGTH		0x910
119 #define SE_GENI_S_GP_LENGTH		0x914
120 #define SE_DMA_TX_PTR_L			0xc30
121 #define SE_DMA_TX_PTR_H			0xc34
122 #define SE_DMA_TX_ATTR			0xc38
123 #define SE_DMA_TX_LEN			0xc3c
124 #define SE_DMA_TX_IRQ_EN		0xc48
125 #define SE_DMA_TX_IRQ_EN_SET		0xc4c
126 #define SE_DMA_TX_IRQ_EN_CLR		0xc50
127 #define SE_DMA_TX_LEN_IN		0xc54
128 #define SE_DMA_TX_MAX_BURST		0xc5c
129 #define SE_DMA_RX_PTR_L			0xd30
130 #define SE_DMA_RX_PTR_H			0xd34
131 #define SE_DMA_RX_ATTR			0xd38
132 #define SE_DMA_RX_LEN			0xd3c
133 #define SE_DMA_RX_IRQ_EN		0xd48
134 #define SE_DMA_RX_IRQ_EN_SET		0xd4c
135 #define SE_DMA_RX_IRQ_EN_CLR		0xd50
136 #define SE_DMA_RX_LEN_IN		0xd54
137 #define SE_DMA_RX_MAX_BURST		0xd5c
138 #define SE_DMA_RX_FLUSH			0xd60
139 #define SE_GSI_EVENT_EN			0xe18
140 #define SE_IRQ_EN			0xe1c
141 #define SE_DMA_GENERAL_CFG		0xe30
142 
143 /* GENI_OUTPUT_CTRL fields */
144 #define DEFAULT_IO_OUTPUT_CTRL_MSK	GENMASK(6, 0)
145 
146 /* GENI_CGC_CTRL fields */
147 #define CFG_AHB_CLK_CGC_ON		BIT(0)
148 #define CFG_AHB_WR_ACLK_CGC_ON		BIT(1)
149 #define DATA_AHB_CLK_CGC_ON		BIT(2)
150 #define SCLK_CGC_ON			BIT(3)
151 #define TX_CLK_CGC_ON			BIT(4)
152 #define RX_CLK_CGC_ON			BIT(5)
153 #define EXT_CLK_CGC_ON			BIT(6)
154 #define PROG_RAM_HCLK_OFF		BIT(8)
155 #define PROG_RAM_SCLK_OFF		BIT(9)
156 #define DEFAULT_CGC_EN			GENMASK(6, 0)
157 
158 /* SE_GSI_EVENT_EN fields */
159 #define DMA_RX_EVENT_EN			BIT(0)
160 #define DMA_TX_EVENT_EN			BIT(1)
161 #define GENI_M_EVENT_EN			BIT(2)
162 #define GENI_S_EVENT_EN			BIT(3)
163 
164 /* SE_IRQ_EN fields */
165 #define DMA_RX_IRQ_EN			BIT(0)
166 #define DMA_TX_IRQ_EN			BIT(1)
167 #define GENI_M_IRQ_EN			BIT(2)
168 #define GENI_S_IRQ_EN			BIT(3)
169 
170 /* SE_DMA_GENERAL_CFG */
171 #define DMA_RX_CLK_CGC_ON		BIT(0)
172 #define DMA_TX_CLK_CGC_ON		BIT(1)
173 #define DMA_AHB_SLV_CFG_ON		BIT(2)
174 #define AHB_SEC_SLV_CLK_CGC_ON		BIT(3)
175 #define DUMMY_RX_NON_BUFFERABLE		BIT(4)
176 #define RX_DMA_ZERO_PADDING_EN		BIT(5)
177 #define RX_DMA_IRQ_DELAY_MSK		GENMASK(8, 6)
178 #define RX_DMA_IRQ_DELAY_SHFT		6
179 
180 /**
181  * geni_se_get_qup_hw_version() - Read the QUP wrapper Hardware version
182  * @se:	Pointer to the corresponding serial engine.
183  *
184  * Return: Hardware Version of the wrapper.
185  */
186 u32 geni_se_get_qup_hw_version(struct geni_se *se)
187 {
188 	struct geni_wrapper *wrapper = se->wrapper;
189 
190 	return readl_relaxed(wrapper->base + QUP_HW_VER_REG);
191 }
192 EXPORT_SYMBOL(geni_se_get_qup_hw_version);
193 
194 static void geni_se_io_set_mode(void __iomem *base)
195 {
196 	u32 val;
197 
198 	val = readl_relaxed(base + SE_IRQ_EN);
199 	val |= GENI_M_IRQ_EN | GENI_S_IRQ_EN;
200 	val |= DMA_TX_IRQ_EN | DMA_RX_IRQ_EN;
201 	writel_relaxed(val, base + SE_IRQ_EN);
202 
203 	val = readl_relaxed(base + SE_GENI_DMA_MODE_EN);
204 	val &= ~GENI_DMA_MODE_EN;
205 	writel_relaxed(val, base + SE_GENI_DMA_MODE_EN);
206 
207 	writel_relaxed(0, base + SE_GSI_EVENT_EN);
208 }
209 
210 static void geni_se_io_init(void __iomem *base)
211 {
212 	u32 val;
213 
214 	val = readl_relaxed(base + GENI_CGC_CTRL);
215 	val |= DEFAULT_CGC_EN;
216 	writel_relaxed(val, base + GENI_CGC_CTRL);
217 
218 	val = readl_relaxed(base + SE_DMA_GENERAL_CFG);
219 	val |= AHB_SEC_SLV_CLK_CGC_ON | DMA_AHB_SLV_CFG_ON;
220 	val |= DMA_TX_CLK_CGC_ON | DMA_RX_CLK_CGC_ON;
221 	writel_relaxed(val, base + SE_DMA_GENERAL_CFG);
222 
223 	writel_relaxed(DEFAULT_IO_OUTPUT_CTRL_MSK, base + GENI_OUTPUT_CTRL);
224 	writel_relaxed(FORCE_DEFAULT, base + GENI_FORCE_DEFAULT_REG);
225 }
226 
227 static void geni_se_irq_clear(struct geni_se *se)
228 {
229 	writel_relaxed(0, se->base + SE_GSI_EVENT_EN);
230 	writel_relaxed(0xffffffff, se->base + SE_GENI_M_IRQ_CLEAR);
231 	writel_relaxed(0xffffffff, se->base + SE_GENI_S_IRQ_CLEAR);
232 	writel_relaxed(0xffffffff, se->base + SE_DMA_TX_IRQ_CLR);
233 	writel_relaxed(0xffffffff, se->base + SE_DMA_RX_IRQ_CLR);
234 	writel_relaxed(0xffffffff, se->base + SE_IRQ_EN);
235 }
236 
237 /**
238  * geni_se_init() - Initialize the GENI serial engine
239  * @se:		Pointer to the concerned serial engine.
240  * @rx_wm:	Receive watermark, in units of FIFO words.
241  * @rx_rfr:	Ready-for-receive watermark, in units of FIFO words.
242  *
243  * This function is used to initialize the GENI serial engine, configure
244  * receive watermark and ready-for-receive watermarks.
245  */
246 void geni_se_init(struct geni_se *se, u32 rx_wm, u32 rx_rfr)
247 {
248 	u32 val;
249 
250 	geni_se_irq_clear(se);
251 	geni_se_io_init(se->base);
252 	geni_se_io_set_mode(se->base);
253 
254 	writel_relaxed(rx_wm, se->base + SE_GENI_RX_WATERMARK_REG);
255 	writel_relaxed(rx_rfr, se->base + SE_GENI_RX_RFR_WATERMARK_REG);
256 
257 	val = readl_relaxed(se->base + SE_GENI_M_IRQ_EN);
258 	val |= M_COMMON_GENI_M_IRQ_EN;
259 	writel_relaxed(val, se->base + SE_GENI_M_IRQ_EN);
260 
261 	val = readl_relaxed(se->base + SE_GENI_S_IRQ_EN);
262 	val |= S_COMMON_GENI_S_IRQ_EN;
263 	writel_relaxed(val, se->base + SE_GENI_S_IRQ_EN);
264 }
265 EXPORT_SYMBOL(geni_se_init);
266 
267 static void geni_se_select_fifo_mode(struct geni_se *se)
268 {
269 	u32 proto = geni_se_read_proto(se);
270 	u32 val, val_old;
271 
272 	geni_se_irq_clear(se);
273 
274 	/*
275 	 * The RX path for the UART is asynchronous and so needs more
276 	 * complex logic for enabling / disabling its interrupts.
277 	 *
278 	 * Specific notes:
279 	 * - The done and TX-related interrupts are managed manually.
280 	 * - We don't RX from the main sequencer (we use the secondary) so
281 	 *   we don't need the RX-related interrupts enabled in the main
282 	 *   sequencer for UART.
283 	 */
284 	if (proto != GENI_SE_UART) {
285 		val_old = val = readl_relaxed(se->base + SE_GENI_M_IRQ_EN);
286 		val |= M_CMD_DONE_EN | M_TX_FIFO_WATERMARK_EN;
287 		val |= M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN;
288 		if (val != val_old)
289 			writel_relaxed(val, se->base + SE_GENI_M_IRQ_EN);
290 
291 		val_old = val = readl_relaxed(se->base + SE_GENI_S_IRQ_EN);
292 		val |= S_CMD_DONE_EN;
293 		if (val != val_old)
294 			writel_relaxed(val, se->base + SE_GENI_S_IRQ_EN);
295 	}
296 
297 	val_old = val = readl_relaxed(se->base + SE_GENI_DMA_MODE_EN);
298 	val &= ~GENI_DMA_MODE_EN;
299 	if (val != val_old)
300 		writel_relaxed(val, se->base + SE_GENI_DMA_MODE_EN);
301 }
302 
303 static void geni_se_select_dma_mode(struct geni_se *se)
304 {
305 	u32 proto = geni_se_read_proto(se);
306 	u32 val, val_old;
307 
308 	geni_se_irq_clear(se);
309 
310 	if (proto != GENI_SE_UART) {
311 		val_old = val = readl_relaxed(se->base + SE_GENI_M_IRQ_EN);
312 		val &= ~(M_CMD_DONE_EN | M_TX_FIFO_WATERMARK_EN);
313 		val &= ~(M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN);
314 		if (val != val_old)
315 			writel_relaxed(val, se->base + SE_GENI_M_IRQ_EN);
316 
317 		val_old = val = readl_relaxed(se->base + SE_GENI_S_IRQ_EN);
318 		val &= ~S_CMD_DONE_EN;
319 		if (val != val_old)
320 			writel_relaxed(val, se->base + SE_GENI_S_IRQ_EN);
321 	}
322 
323 	val_old = val = readl_relaxed(se->base + SE_GENI_DMA_MODE_EN);
324 	val |= GENI_DMA_MODE_EN;
325 	if (val != val_old)
326 		writel_relaxed(val, se->base + SE_GENI_DMA_MODE_EN);
327 }
328 
329 /**
330  * geni_se_select_mode() - Select the serial engine transfer mode
331  * @se:		Pointer to the concerned serial engine.
332  * @mode:	Transfer mode to be selected.
333  */
334 void geni_se_select_mode(struct geni_se *se, enum geni_se_xfer_mode mode)
335 {
336 	WARN_ON(mode != GENI_SE_FIFO && mode != GENI_SE_DMA);
337 
338 	switch (mode) {
339 	case GENI_SE_FIFO:
340 		geni_se_select_fifo_mode(se);
341 		break;
342 	case GENI_SE_DMA:
343 		geni_se_select_dma_mode(se);
344 		break;
345 	case GENI_SE_INVALID:
346 	default:
347 		break;
348 	}
349 }
350 EXPORT_SYMBOL(geni_se_select_mode);
351 
352 /**
353  * DOC: Overview
354  *
355  * GENI FIFO packing is highly configurable. TX/RX packing/unpacking consist
356  * of up to 4 operations, each operation represented by 4 configuration vectors
357  * of 10 bits programmed in GENI_TX_PACKING_CFG0 and GENI_TX_PACKING_CFG1 for
358  * TX FIFO and in GENI_RX_PACKING_CFG0 and GENI_RX_PACKING_CFG1 for RX FIFO.
359  * Refer to below examples for detailed bit-field description.
360  *
361  * Example 1: word_size = 7, packing_mode = 4 x 8, msb_to_lsb = 1
362  *
363  *        +-----------+-------+-------+-------+-------+
364  *        |           | vec_0 | vec_1 | vec_2 | vec_3 |
365  *        +-----------+-------+-------+-------+-------+
366  *        | start     | 0x6   | 0xe   | 0x16  | 0x1e  |
367  *        | direction | 1     | 1     | 1     | 1     |
368  *        | length    | 6     | 6     | 6     | 6     |
369  *        | stop      | 0     | 0     | 0     | 1     |
370  *        +-----------+-------+-------+-------+-------+
371  *
372  * Example 2: word_size = 15, packing_mode = 2 x 16, msb_to_lsb = 0
373  *
374  *        +-----------+-------+-------+-------+-------+
375  *        |           | vec_0 | vec_1 | vec_2 | vec_3 |
376  *        +-----------+-------+-------+-------+-------+
377  *        | start     | 0x0   | 0x8   | 0x10  | 0x18  |
378  *        | direction | 0     | 0     | 0     | 0     |
379  *        | length    | 7     | 6     | 7     | 6     |
380  *        | stop      | 0     | 0     | 0     | 1     |
381  *        +-----------+-------+-------+-------+-------+
382  *
383  * Example 3: word_size = 23, packing_mode = 1 x 32, msb_to_lsb = 1
384  *
385  *        +-----------+-------+-------+-------+-------+
386  *        |           | vec_0 | vec_1 | vec_2 | vec_3 |
387  *        +-----------+-------+-------+-------+-------+
388  *        | start     | 0x16  | 0xe   | 0x6   | 0x0   |
389  *        | direction | 1     | 1     | 1     | 1     |
390  *        | length    | 7     | 7     | 6     | 0     |
391  *        | stop      | 0     | 0     | 1     | 0     |
392  *        +-----------+-------+-------+-------+-------+
393  *
394  */
395 
396 #define NUM_PACKING_VECTORS 4
397 #define PACKING_START_SHIFT 5
398 #define PACKING_DIR_SHIFT 4
399 #define PACKING_LEN_SHIFT 1
400 #define PACKING_STOP_BIT BIT(0)
401 #define PACKING_VECTOR_SHIFT 10
402 /**
403  * geni_se_config_packing() - Packing configuration of the serial engine
404  * @se:		Pointer to the concerned serial engine
405  * @bpw:	Bits of data per transfer word.
406  * @pack_words:	Number of words per fifo element.
407  * @msb_to_lsb:	Transfer from MSB to LSB or vice-versa.
408  * @tx_cfg:	Flag to configure the TX Packing.
409  * @rx_cfg:	Flag to configure the RX Packing.
410  *
411  * This function is used to configure the packing rules for the current
412  * transfer.
413  */
414 void geni_se_config_packing(struct geni_se *se, int bpw, int pack_words,
415 			    bool msb_to_lsb, bool tx_cfg, bool rx_cfg)
416 {
417 	u32 cfg0, cfg1, cfg[NUM_PACKING_VECTORS] = {0};
418 	int len;
419 	int temp_bpw = bpw;
420 	int idx_start = msb_to_lsb ? bpw - 1 : 0;
421 	int idx = idx_start;
422 	int idx_delta = msb_to_lsb ? -BITS_PER_BYTE : BITS_PER_BYTE;
423 	int ceil_bpw = ALIGN(bpw, BITS_PER_BYTE);
424 	int iter = (ceil_bpw * pack_words) / BITS_PER_BYTE;
425 	int i;
426 
427 	if (iter <= 0 || iter > NUM_PACKING_VECTORS)
428 		return;
429 
430 	for (i = 0; i < iter; i++) {
431 		len = min_t(int, temp_bpw, BITS_PER_BYTE) - 1;
432 		cfg[i] = idx << PACKING_START_SHIFT;
433 		cfg[i] |= msb_to_lsb << PACKING_DIR_SHIFT;
434 		cfg[i] |= len << PACKING_LEN_SHIFT;
435 
436 		if (temp_bpw <= BITS_PER_BYTE) {
437 			idx = ((i + 1) * BITS_PER_BYTE) + idx_start;
438 			temp_bpw = bpw;
439 		} else {
440 			idx = idx + idx_delta;
441 			temp_bpw = temp_bpw - BITS_PER_BYTE;
442 		}
443 	}
444 	cfg[iter - 1] |= PACKING_STOP_BIT;
445 	cfg0 = cfg[0] | (cfg[1] << PACKING_VECTOR_SHIFT);
446 	cfg1 = cfg[2] | (cfg[3] << PACKING_VECTOR_SHIFT);
447 
448 	if (tx_cfg) {
449 		writel_relaxed(cfg0, se->base + SE_GENI_TX_PACKING_CFG0);
450 		writel_relaxed(cfg1, se->base + SE_GENI_TX_PACKING_CFG1);
451 	}
452 	if (rx_cfg) {
453 		writel_relaxed(cfg0, se->base + SE_GENI_RX_PACKING_CFG0);
454 		writel_relaxed(cfg1, se->base + SE_GENI_RX_PACKING_CFG1);
455 	}
456 
457 	/*
458 	 * Number of protocol words in each FIFO entry
459 	 * 0 - 4x8, four words in each entry, max word size of 8 bits
460 	 * 1 - 2x16, two words in each entry, max word size of 16 bits
461 	 * 2 - 1x32, one word in each entry, max word size of 32 bits
462 	 * 3 - undefined
463 	 */
464 	if (pack_words || bpw == 32)
465 		writel_relaxed(bpw / 16, se->base + SE_GENI_BYTE_GRAN);
466 }
467 EXPORT_SYMBOL(geni_se_config_packing);
468 
469 static void geni_se_clks_off(struct geni_se *se)
470 {
471 	struct geni_wrapper *wrapper = se->wrapper;
472 
473 	clk_disable_unprepare(se->clk);
474 	clk_bulk_disable_unprepare(ARRAY_SIZE(wrapper->ahb_clks),
475 						wrapper->ahb_clks);
476 }
477 
478 /**
479  * geni_se_resources_off() - Turn off resources associated with the serial
480  *                           engine
481  * @se:	Pointer to the concerned serial engine.
482  *
483  * Return: 0 on success, standard Linux error codes on failure/error.
484  */
485 int geni_se_resources_off(struct geni_se *se)
486 {
487 	int ret;
488 
489 	if (has_acpi_companion(se->dev))
490 		return 0;
491 
492 	ret = pinctrl_pm_select_sleep_state(se->dev);
493 	if (ret)
494 		return ret;
495 
496 	geni_se_clks_off(se);
497 	return 0;
498 }
499 EXPORT_SYMBOL(geni_se_resources_off);
500 
501 static int geni_se_clks_on(struct geni_se *se)
502 {
503 	int ret;
504 	struct geni_wrapper *wrapper = se->wrapper;
505 
506 	ret = clk_bulk_prepare_enable(ARRAY_SIZE(wrapper->ahb_clks),
507 						wrapper->ahb_clks);
508 	if (ret)
509 		return ret;
510 
511 	ret = clk_prepare_enable(se->clk);
512 	if (ret)
513 		clk_bulk_disable_unprepare(ARRAY_SIZE(wrapper->ahb_clks),
514 							wrapper->ahb_clks);
515 	return ret;
516 }
517 
518 /**
519  * geni_se_resources_on() - Turn on resources associated with the serial
520  *                          engine
521  * @se:	Pointer to the concerned serial engine.
522  *
523  * Return: 0 on success, standard Linux error codes on failure/error.
524  */
525 int geni_se_resources_on(struct geni_se *se)
526 {
527 	int ret;
528 
529 	if (has_acpi_companion(se->dev))
530 		return 0;
531 
532 	ret = geni_se_clks_on(se);
533 	if (ret)
534 		return ret;
535 
536 	ret = pinctrl_pm_select_default_state(se->dev);
537 	if (ret)
538 		geni_se_clks_off(se);
539 
540 	return ret;
541 }
542 EXPORT_SYMBOL(geni_se_resources_on);
543 
544 /**
545  * geni_se_clk_tbl_get() - Get the clock table to program DFS
546  * @se:		Pointer to the concerned serial engine.
547  * @tbl:	Table in which the output is returned.
548  *
549  * This function is called by the protocol drivers to determine the different
550  * clock frequencies supported by serial engine core clock. The protocol
551  * drivers use the output to determine the clock frequency index to be
552  * programmed into DFS.
553  *
554  * Return: number of valid performance levels in the table on success,
555  *	   standard Linux error codes on failure.
556  */
557 int geni_se_clk_tbl_get(struct geni_se *se, unsigned long **tbl)
558 {
559 	long freq = 0;
560 	int i;
561 
562 	if (se->clk_perf_tbl) {
563 		*tbl = se->clk_perf_tbl;
564 		return se->num_clk_levels;
565 	}
566 
567 	se->clk_perf_tbl = devm_kcalloc(se->dev, MAX_CLK_PERF_LEVEL,
568 					sizeof(*se->clk_perf_tbl),
569 					GFP_KERNEL);
570 	if (!se->clk_perf_tbl)
571 		return -ENOMEM;
572 
573 	for (i = 0; i < MAX_CLK_PERF_LEVEL; i++) {
574 		freq = clk_round_rate(se->clk, freq + 1);
575 		if (freq <= 0 || freq == se->clk_perf_tbl[i - 1])
576 			break;
577 		se->clk_perf_tbl[i] = freq;
578 	}
579 	se->num_clk_levels = i;
580 	*tbl = se->clk_perf_tbl;
581 	return se->num_clk_levels;
582 }
583 EXPORT_SYMBOL(geni_se_clk_tbl_get);
584 
585 /**
586  * geni_se_clk_freq_match() - Get the matching or closest SE clock frequency
587  * @se:		Pointer to the concerned serial engine.
588  * @req_freq:	Requested clock frequency.
589  * @index:	Index of the resultant frequency in the table.
590  * @res_freq:	Resultant frequency of the source clock.
591  * @exact:	Flag to indicate exact multiple requirement of the requested
592  *		frequency.
593  *
594  * This function is called by the protocol drivers to determine the best match
595  * of the requested frequency as provided by the serial engine clock in order
596  * to meet the performance requirements.
597  *
598  * If we return success:
599  * - if @exact is true  then @res_freq / <an_integer> == @req_freq
600  * - if @exact is false then @res_freq / <an_integer> <= @req_freq
601  *
602  * Return: 0 on success, standard Linux error codes on failure.
603  */
604 int geni_se_clk_freq_match(struct geni_se *se, unsigned long req_freq,
605 			   unsigned int *index, unsigned long *res_freq,
606 			   bool exact)
607 {
608 	unsigned long *tbl;
609 	int num_clk_levels;
610 	int i;
611 	unsigned long best_delta;
612 	unsigned long new_delta;
613 	unsigned int divider;
614 
615 	num_clk_levels = geni_se_clk_tbl_get(se, &tbl);
616 	if (num_clk_levels < 0)
617 		return num_clk_levels;
618 
619 	if (num_clk_levels == 0)
620 		return -EINVAL;
621 
622 	best_delta = ULONG_MAX;
623 	for (i = 0; i < num_clk_levels; i++) {
624 		divider = DIV_ROUND_UP(tbl[i], req_freq);
625 		new_delta = req_freq - tbl[i] / divider;
626 		if (new_delta < best_delta) {
627 			/* We have a new best! */
628 			*index = i;
629 			*res_freq = tbl[i];
630 
631 			/* If the new best is exact then we're done */
632 			if (new_delta == 0)
633 				return 0;
634 
635 			/* Record how close we got */
636 			best_delta = new_delta;
637 		}
638 	}
639 
640 	if (exact)
641 		return -EINVAL;
642 
643 	return 0;
644 }
645 EXPORT_SYMBOL(geni_se_clk_freq_match);
646 
647 #define GENI_SE_DMA_DONE_EN BIT(0)
648 #define GENI_SE_DMA_EOT_EN BIT(1)
649 #define GENI_SE_DMA_AHB_ERR_EN BIT(2)
650 #define GENI_SE_DMA_EOT_BUF BIT(0)
651 /**
652  * geni_se_tx_dma_prep() - Prepare the serial engine for TX DMA transfer
653  * @se:			Pointer to the concerned serial engine.
654  * @buf:		Pointer to the TX buffer.
655  * @len:		Length of the TX buffer.
656  * @iova:		Pointer to store the mapped DMA address.
657  *
658  * This function is used to prepare the buffers for DMA TX.
659  *
660  * Return: 0 on success, standard Linux error codes on failure.
661  */
662 int geni_se_tx_dma_prep(struct geni_se *se, void *buf, size_t len,
663 			dma_addr_t *iova)
664 {
665 	struct geni_wrapper *wrapper = se->wrapper;
666 	u32 val;
667 
668 	if (!wrapper)
669 		return -EINVAL;
670 
671 	*iova = dma_map_single(wrapper->dev, buf, len, DMA_TO_DEVICE);
672 	if (dma_mapping_error(wrapper->dev, *iova))
673 		return -EIO;
674 
675 	val = GENI_SE_DMA_DONE_EN;
676 	val |= GENI_SE_DMA_EOT_EN;
677 	val |= GENI_SE_DMA_AHB_ERR_EN;
678 	writel_relaxed(val, se->base + SE_DMA_TX_IRQ_EN_SET);
679 	writel_relaxed(lower_32_bits(*iova), se->base + SE_DMA_TX_PTR_L);
680 	writel_relaxed(upper_32_bits(*iova), se->base + SE_DMA_TX_PTR_H);
681 	writel_relaxed(GENI_SE_DMA_EOT_BUF, se->base + SE_DMA_TX_ATTR);
682 	writel(len, se->base + SE_DMA_TX_LEN);
683 	return 0;
684 }
685 EXPORT_SYMBOL(geni_se_tx_dma_prep);
686 
687 /**
688  * geni_se_rx_dma_prep() - Prepare the serial engine for RX DMA transfer
689  * @se:			Pointer to the concerned serial engine.
690  * @buf:		Pointer to the RX buffer.
691  * @len:		Length of the RX buffer.
692  * @iova:		Pointer to store the mapped DMA address.
693  *
694  * This function is used to prepare the buffers for DMA RX.
695  *
696  * Return: 0 on success, standard Linux error codes on failure.
697  */
698 int geni_se_rx_dma_prep(struct geni_se *se, void *buf, size_t len,
699 			dma_addr_t *iova)
700 {
701 	struct geni_wrapper *wrapper = se->wrapper;
702 	u32 val;
703 
704 	if (!wrapper)
705 		return -EINVAL;
706 
707 	*iova = dma_map_single(wrapper->dev, buf, len, DMA_FROM_DEVICE);
708 	if (dma_mapping_error(wrapper->dev, *iova))
709 		return -EIO;
710 
711 	val = GENI_SE_DMA_DONE_EN;
712 	val |= GENI_SE_DMA_EOT_EN;
713 	val |= GENI_SE_DMA_AHB_ERR_EN;
714 	writel_relaxed(val, se->base + SE_DMA_RX_IRQ_EN_SET);
715 	writel_relaxed(lower_32_bits(*iova), se->base + SE_DMA_RX_PTR_L);
716 	writel_relaxed(upper_32_bits(*iova), se->base + SE_DMA_RX_PTR_H);
717 	/* RX does not have EOT buffer type bit. So just reset RX_ATTR */
718 	writel_relaxed(0, se->base + SE_DMA_RX_ATTR);
719 	writel(len, se->base + SE_DMA_RX_LEN);
720 	return 0;
721 }
722 EXPORT_SYMBOL(geni_se_rx_dma_prep);
723 
724 /**
725  * geni_se_tx_dma_unprep() - Unprepare the serial engine after TX DMA transfer
726  * @se:			Pointer to the concerned serial engine.
727  * @iova:		DMA address of the TX buffer.
728  * @len:		Length of the TX buffer.
729  *
730  * This function is used to unprepare the DMA buffers after DMA TX.
731  */
732 void geni_se_tx_dma_unprep(struct geni_se *se, dma_addr_t iova, size_t len)
733 {
734 	struct geni_wrapper *wrapper = se->wrapper;
735 
736 	if (!dma_mapping_error(wrapper->dev, iova))
737 		dma_unmap_single(wrapper->dev, iova, len, DMA_TO_DEVICE);
738 }
739 EXPORT_SYMBOL(geni_se_tx_dma_unprep);
740 
741 /**
742  * geni_se_rx_dma_unprep() - Unprepare the serial engine after RX DMA transfer
743  * @se:			Pointer to the concerned serial engine.
744  * @iova:		DMA address of the RX buffer.
745  * @len:		Length of the RX buffer.
746  *
747  * This function is used to unprepare the DMA buffers after DMA RX.
748  */
749 void geni_se_rx_dma_unprep(struct geni_se *se, dma_addr_t iova, size_t len)
750 {
751 	struct geni_wrapper *wrapper = se->wrapper;
752 
753 	if (!dma_mapping_error(wrapper->dev, iova))
754 		dma_unmap_single(wrapper->dev, iova, len, DMA_FROM_DEVICE);
755 }
756 EXPORT_SYMBOL(geni_se_rx_dma_unprep);
757 
758 int geni_icc_get(struct geni_se *se, const char *icc_ddr)
759 {
760 	int i, err;
761 	const char *icc_names[] = {"qup-core", "qup-config", icc_ddr};
762 
763 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
764 		if (!icc_names[i])
765 			continue;
766 
767 		se->icc_paths[i].path = devm_of_icc_get(se->dev, icc_names[i]);
768 		if (IS_ERR(se->icc_paths[i].path))
769 			goto err;
770 	}
771 
772 	return 0;
773 
774 err:
775 	err = PTR_ERR(se->icc_paths[i].path);
776 	if (err != -EPROBE_DEFER)
777 		dev_err_ratelimited(se->dev, "Failed to get ICC path '%s': %d\n",
778 					icc_names[i], err);
779 	return err;
780 
781 }
782 EXPORT_SYMBOL(geni_icc_get);
783 
784 int geni_icc_set_bw(struct geni_se *se)
785 {
786 	int i, ret;
787 
788 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
789 		ret = icc_set_bw(se->icc_paths[i].path,
790 			se->icc_paths[i].avg_bw, se->icc_paths[i].avg_bw);
791 		if (ret) {
792 			dev_err_ratelimited(se->dev, "ICC BW voting failed on path '%s': %d\n",
793 					icc_path_names[i], ret);
794 			return ret;
795 		}
796 	}
797 
798 	return 0;
799 }
800 EXPORT_SYMBOL(geni_icc_set_bw);
801 
802 void geni_icc_set_tag(struct geni_se *se, u32 tag)
803 {
804 	int i;
805 
806 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++)
807 		icc_set_tag(se->icc_paths[i].path, tag);
808 }
809 EXPORT_SYMBOL(geni_icc_set_tag);
810 
811 /* To do: Replace this by icc_bulk_enable once it's implemented in ICC core */
812 int geni_icc_enable(struct geni_se *se)
813 {
814 	int i, ret;
815 
816 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
817 		ret = icc_enable(se->icc_paths[i].path);
818 		if (ret) {
819 			dev_err_ratelimited(se->dev, "ICC enable failed on path '%s': %d\n",
820 					icc_path_names[i], ret);
821 			return ret;
822 		}
823 	}
824 
825 	return 0;
826 }
827 EXPORT_SYMBOL(geni_icc_enable);
828 
829 int geni_icc_disable(struct geni_se *se)
830 {
831 	int i, ret;
832 
833 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
834 		ret = icc_disable(se->icc_paths[i].path);
835 		if (ret) {
836 			dev_err_ratelimited(se->dev, "ICC disable failed on path '%s': %d\n",
837 					icc_path_names[i], ret);
838 			return ret;
839 		}
840 	}
841 
842 	return 0;
843 }
844 EXPORT_SYMBOL(geni_icc_disable);
845 
846 void geni_remove_earlycon_icc_vote(void)
847 {
848 	struct platform_device *pdev;
849 	struct geni_wrapper *wrapper;
850 	struct device_node *parent;
851 	struct device_node *child;
852 
853 	if (!earlycon_wrapper)
854 		return;
855 
856 	wrapper = earlycon_wrapper;
857 	parent = of_get_next_parent(wrapper->dev->of_node);
858 	for_each_child_of_node(parent, child) {
859 		if (!of_device_is_compatible(child, "qcom,geni-se-qup"))
860 			continue;
861 
862 		pdev = of_find_device_by_node(child);
863 		if (!pdev)
864 			continue;
865 
866 		wrapper = platform_get_drvdata(pdev);
867 		icc_put(wrapper->to_core.path);
868 		wrapper->to_core.path = NULL;
869 
870 	}
871 	of_node_put(parent);
872 
873 	earlycon_wrapper = NULL;
874 }
875 EXPORT_SYMBOL(geni_remove_earlycon_icc_vote);
876 
877 static int geni_se_probe(struct platform_device *pdev)
878 {
879 	struct device *dev = &pdev->dev;
880 	struct resource *res;
881 	struct geni_wrapper *wrapper;
882 	struct console __maybe_unused *bcon;
883 	bool __maybe_unused has_earlycon = false;
884 	int ret;
885 
886 	wrapper = devm_kzalloc(dev, sizeof(*wrapper), GFP_KERNEL);
887 	if (!wrapper)
888 		return -ENOMEM;
889 
890 	wrapper->dev = dev;
891 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
892 	wrapper->base = devm_ioremap_resource(dev, res);
893 	if (IS_ERR(wrapper->base))
894 		return PTR_ERR(wrapper->base);
895 
896 	if (!has_acpi_companion(&pdev->dev)) {
897 		wrapper->ahb_clks[0].id = "m-ahb";
898 		wrapper->ahb_clks[1].id = "s-ahb";
899 		ret = devm_clk_bulk_get(dev, NUM_AHB_CLKS, wrapper->ahb_clks);
900 		if (ret) {
901 			dev_err(dev, "Err getting AHB clks %d\n", ret);
902 			return ret;
903 		}
904 	}
905 
906 #ifdef CONFIG_SERIAL_EARLYCON
907 	for_each_console(bcon) {
908 		if (!strcmp(bcon->name, "qcom_geni")) {
909 			has_earlycon = true;
910 			break;
911 		}
912 	}
913 	if (!has_earlycon)
914 		goto exit;
915 
916 	wrapper->to_core.path = devm_of_icc_get(dev, "qup-core");
917 	if (IS_ERR(wrapper->to_core.path))
918 		return PTR_ERR(wrapper->to_core.path);
919 	/*
920 	 * Put minmal BW request on core clocks on behalf of early console.
921 	 * The vote will be removed earlycon exit function.
922 	 *
923 	 * Note: We are putting vote on each QUP wrapper instead only to which
924 	 * earlycon is connected because QUP core clock of different wrapper
925 	 * share same voltage domain. If core1 is put to 0, then core2 will
926 	 * also run at 0, if not voted. Default ICC vote will be removed ASA
927 	 * we touch any of the core clock.
928 	 * core1 = core2 = max(core1, core2)
929 	 */
930 	ret = icc_set_bw(wrapper->to_core.path, GENI_DEFAULT_BW,
931 				GENI_DEFAULT_BW);
932 	if (ret) {
933 		dev_err(&pdev->dev, "%s: ICC BW voting failed for core: %d\n",
934 			__func__, ret);
935 		return ret;
936 	}
937 
938 	if (of_get_compatible_child(pdev->dev.of_node, "qcom,geni-debug-uart"))
939 		earlycon_wrapper = wrapper;
940 	of_node_put(pdev->dev.of_node);
941 exit:
942 #endif
943 	dev_set_drvdata(dev, wrapper);
944 	dev_dbg(dev, "GENI SE Driver probed\n");
945 	return devm_of_platform_populate(dev);
946 }
947 
948 static const struct of_device_id geni_se_dt_match[] = {
949 	{ .compatible = "qcom,geni-se-qup", },
950 	{}
951 };
952 MODULE_DEVICE_TABLE(of, geni_se_dt_match);
953 
954 static struct platform_driver geni_se_driver = {
955 	.driver = {
956 		.name = "geni_se_qup",
957 		.of_match_table = geni_se_dt_match,
958 	},
959 	.probe = geni_se_probe,
960 };
961 module_platform_driver(geni_se_driver);
962 
963 MODULE_DESCRIPTION("GENI Serial Engine Driver");
964 MODULE_LICENSE("GPL v2");
965