xref: /openbmc/linux/drivers/soc/qcom/qcom-geni-se.c (revision f5ad1c74)
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, val_old;
270 
271 	geni_se_irq_clear(se);
272 
273 	/*
274 	 * The RX path for the UART is asynchronous and so needs more
275 	 * complex logic for enabling / disabling its interrupts.
276 	 *
277 	 * Specific notes:
278 	 * - The done and TX-related interrupts are managed manually.
279 	 * - We don't RX from the main sequencer (we use the secondary) so
280 	 *   we don't need the RX-related interrupts enabled in the main
281 	 *   sequencer for UART.
282 	 */
283 	if (proto != GENI_SE_UART) {
284 		val_old = val = readl_relaxed(se->base + SE_GENI_M_IRQ_EN);
285 		val |= M_CMD_DONE_EN | M_TX_FIFO_WATERMARK_EN;
286 		val |= M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN;
287 		if (val != val_old)
288 			writel_relaxed(val, se->base + SE_GENI_M_IRQ_EN);
289 
290 		val_old = val = readl_relaxed(se->base + SE_GENI_S_IRQ_EN);
291 		val |= S_CMD_DONE_EN;
292 		if (val != val_old)
293 			writel_relaxed(val, se->base + SE_GENI_S_IRQ_EN);
294 	}
295 
296 	val_old = val = readl_relaxed(se->base + SE_GENI_DMA_MODE_EN);
297 	val &= ~GENI_DMA_MODE_EN;
298 	if (val != val_old)
299 		writel_relaxed(val, se->base + SE_GENI_DMA_MODE_EN);
300 }
301 
302 static void geni_se_select_dma_mode(struct geni_se *se)
303 {
304 	u32 proto = geni_se_read_proto(se);
305 	u32 val, val_old;
306 
307 	geni_se_irq_clear(se);
308 
309 	if (proto != GENI_SE_UART) {
310 		val_old = val = readl_relaxed(se->base + SE_GENI_M_IRQ_EN);
311 		val &= ~(M_CMD_DONE_EN | M_TX_FIFO_WATERMARK_EN);
312 		val &= ~(M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN);
313 		if (val != val_old)
314 			writel_relaxed(val, se->base + SE_GENI_M_IRQ_EN);
315 
316 		val_old = val = readl_relaxed(se->base + SE_GENI_S_IRQ_EN);
317 		val &= ~S_CMD_DONE_EN;
318 		if (val != val_old)
319 			writel_relaxed(val, se->base + SE_GENI_S_IRQ_EN);
320 	}
321 
322 	val_old = val = readl_relaxed(se->base + SE_GENI_DMA_MODE_EN);
323 	val |= GENI_DMA_MODE_EN;
324 	if (val != val_old)
325 		writel_relaxed(val, se->base + SE_GENI_DMA_MODE_EN);
326 }
327 
328 /**
329  * geni_se_select_mode() - Select the serial engine transfer mode
330  * @se:		Pointer to the concerned serial engine.
331  * @mode:	Transfer mode to be selected.
332  */
333 void geni_se_select_mode(struct geni_se *se, enum geni_se_xfer_mode mode)
334 {
335 	WARN_ON(mode != GENI_SE_FIFO && mode != GENI_SE_DMA);
336 
337 	switch (mode) {
338 	case GENI_SE_FIFO:
339 		geni_se_select_fifo_mode(se);
340 		break;
341 	case GENI_SE_DMA:
342 		geni_se_select_dma_mode(se);
343 		break;
344 	case GENI_SE_INVALID:
345 	default:
346 		break;
347 	}
348 }
349 EXPORT_SYMBOL(geni_se_select_mode);
350 
351 /**
352  * DOC: Overview
353  *
354  * GENI FIFO packing is highly configurable. TX/RX packing/unpacking consist
355  * of up to 4 operations, each operation represented by 4 configuration vectors
356  * of 10 bits programmed in GENI_TX_PACKING_CFG0 and GENI_TX_PACKING_CFG1 for
357  * TX FIFO and in GENI_RX_PACKING_CFG0 and GENI_RX_PACKING_CFG1 for RX FIFO.
358  * Refer to below examples for detailed bit-field description.
359  *
360  * Example 1: word_size = 7, packing_mode = 4 x 8, msb_to_lsb = 1
361  *
362  *        +-----------+-------+-------+-------+-------+
363  *        |           | vec_0 | vec_1 | vec_2 | vec_3 |
364  *        +-----------+-------+-------+-------+-------+
365  *        | start     | 0x6   | 0xe   | 0x16  | 0x1e  |
366  *        | direction | 1     | 1     | 1     | 1     |
367  *        | length    | 6     | 6     | 6     | 6     |
368  *        | stop      | 0     | 0     | 0     | 1     |
369  *        +-----------+-------+-------+-------+-------+
370  *
371  * Example 2: word_size = 15, packing_mode = 2 x 16, msb_to_lsb = 0
372  *
373  *        +-----------+-------+-------+-------+-------+
374  *        |           | vec_0 | vec_1 | vec_2 | vec_3 |
375  *        +-----------+-------+-------+-------+-------+
376  *        | start     | 0x0   | 0x8   | 0x10  | 0x18  |
377  *        | direction | 0     | 0     | 0     | 0     |
378  *        | length    | 7     | 6     | 7     | 6     |
379  *        | stop      | 0     | 0     | 0     | 1     |
380  *        +-----------+-------+-------+-------+-------+
381  *
382  * Example 3: word_size = 23, packing_mode = 1 x 32, msb_to_lsb = 1
383  *
384  *        +-----------+-------+-------+-------+-------+
385  *        |           | vec_0 | vec_1 | vec_2 | vec_3 |
386  *        +-----------+-------+-------+-------+-------+
387  *        | start     | 0x16  | 0xe   | 0x6   | 0x0   |
388  *        | direction | 1     | 1     | 1     | 1     |
389  *        | length    | 7     | 7     | 6     | 0     |
390  *        | stop      | 0     | 0     | 1     | 0     |
391  *        +-----------+-------+-------+-------+-------+
392  *
393  */
394 
395 #define NUM_PACKING_VECTORS 4
396 #define PACKING_START_SHIFT 5
397 #define PACKING_DIR_SHIFT 4
398 #define PACKING_LEN_SHIFT 1
399 #define PACKING_STOP_BIT BIT(0)
400 #define PACKING_VECTOR_SHIFT 10
401 /**
402  * geni_se_config_packing() - Packing configuration of the serial engine
403  * @se:		Pointer to the concerned serial engine
404  * @bpw:	Bits of data per transfer word.
405  * @pack_words:	Number of words per fifo element.
406  * @msb_to_lsb:	Transfer from MSB to LSB or vice-versa.
407  * @tx_cfg:	Flag to configure the TX Packing.
408  * @rx_cfg:	Flag to configure the RX Packing.
409  *
410  * This function is used to configure the packing rules for the current
411  * transfer.
412  */
413 void geni_se_config_packing(struct geni_se *se, int bpw, int pack_words,
414 			    bool msb_to_lsb, bool tx_cfg, bool rx_cfg)
415 {
416 	u32 cfg0, cfg1, cfg[NUM_PACKING_VECTORS] = {0};
417 	int len;
418 	int temp_bpw = bpw;
419 	int idx_start = msb_to_lsb ? bpw - 1 : 0;
420 	int idx = idx_start;
421 	int idx_delta = msb_to_lsb ? -BITS_PER_BYTE : BITS_PER_BYTE;
422 	int ceil_bpw = ALIGN(bpw, BITS_PER_BYTE);
423 	int iter = (ceil_bpw * pack_words) / BITS_PER_BYTE;
424 	int i;
425 
426 	if (iter <= 0 || iter > NUM_PACKING_VECTORS)
427 		return;
428 
429 	for (i = 0; i < iter; i++) {
430 		len = min_t(int, temp_bpw, BITS_PER_BYTE) - 1;
431 		cfg[i] = idx << PACKING_START_SHIFT;
432 		cfg[i] |= msb_to_lsb << PACKING_DIR_SHIFT;
433 		cfg[i] |= len << PACKING_LEN_SHIFT;
434 
435 		if (temp_bpw <= BITS_PER_BYTE) {
436 			idx = ((i + 1) * BITS_PER_BYTE) + idx_start;
437 			temp_bpw = bpw;
438 		} else {
439 			idx = idx + idx_delta;
440 			temp_bpw = temp_bpw - BITS_PER_BYTE;
441 		}
442 	}
443 	cfg[iter - 1] |= PACKING_STOP_BIT;
444 	cfg0 = cfg[0] | (cfg[1] << PACKING_VECTOR_SHIFT);
445 	cfg1 = cfg[2] | (cfg[3] << PACKING_VECTOR_SHIFT);
446 
447 	if (tx_cfg) {
448 		writel_relaxed(cfg0, se->base + SE_GENI_TX_PACKING_CFG0);
449 		writel_relaxed(cfg1, se->base + SE_GENI_TX_PACKING_CFG1);
450 	}
451 	if (rx_cfg) {
452 		writel_relaxed(cfg0, se->base + SE_GENI_RX_PACKING_CFG0);
453 		writel_relaxed(cfg1, se->base + SE_GENI_RX_PACKING_CFG1);
454 	}
455 
456 	/*
457 	 * Number of protocol words in each FIFO entry
458 	 * 0 - 4x8, four words in each entry, max word size of 8 bits
459 	 * 1 - 2x16, two words in each entry, max word size of 16 bits
460 	 * 2 - 1x32, one word in each entry, max word size of 32 bits
461 	 * 3 - undefined
462 	 */
463 	if (pack_words || bpw == 32)
464 		writel_relaxed(bpw / 16, se->base + SE_GENI_BYTE_GRAN);
465 }
466 EXPORT_SYMBOL(geni_se_config_packing);
467 
468 static void geni_se_clks_off(struct geni_se *se)
469 {
470 	struct geni_wrapper *wrapper = se->wrapper;
471 
472 	clk_disable_unprepare(se->clk);
473 	clk_bulk_disable_unprepare(ARRAY_SIZE(wrapper->ahb_clks),
474 						wrapper->ahb_clks);
475 }
476 
477 /**
478  * geni_se_resources_off() - Turn off resources associated with the serial
479  *                           engine
480  * @se:	Pointer to the concerned serial engine.
481  *
482  * Return: 0 on success, standard Linux error codes on failure/error.
483  */
484 int geni_se_resources_off(struct geni_se *se)
485 {
486 	int ret;
487 
488 	if (has_acpi_companion(se->dev))
489 		return 0;
490 
491 	ret = pinctrl_pm_select_sleep_state(se->dev);
492 	if (ret)
493 		return ret;
494 
495 	geni_se_clks_off(se);
496 	return 0;
497 }
498 EXPORT_SYMBOL(geni_se_resources_off);
499 
500 static int geni_se_clks_on(struct geni_se *se)
501 {
502 	int ret;
503 	struct geni_wrapper *wrapper = se->wrapper;
504 
505 	ret = clk_bulk_prepare_enable(ARRAY_SIZE(wrapper->ahb_clks),
506 						wrapper->ahb_clks);
507 	if (ret)
508 		return ret;
509 
510 	ret = clk_prepare_enable(se->clk);
511 	if (ret)
512 		clk_bulk_disable_unprepare(ARRAY_SIZE(wrapper->ahb_clks),
513 							wrapper->ahb_clks);
514 	return ret;
515 }
516 
517 /**
518  * geni_se_resources_on() - Turn on resources associated with the serial
519  *                          engine
520  * @se:	Pointer to the concerned serial engine.
521  *
522  * Return: 0 on success, standard Linux error codes on failure/error.
523  */
524 int geni_se_resources_on(struct geni_se *se)
525 {
526 	int ret;
527 
528 	if (has_acpi_companion(se->dev))
529 		return 0;
530 
531 	ret = geni_se_clks_on(se);
532 	if (ret)
533 		return ret;
534 
535 	ret = pinctrl_pm_select_default_state(se->dev);
536 	if (ret)
537 		geni_se_clks_off(se);
538 
539 	return ret;
540 }
541 EXPORT_SYMBOL(geni_se_resources_on);
542 
543 /**
544  * geni_se_clk_tbl_get() - Get the clock table to program DFS
545  * @se:		Pointer to the concerned serial engine.
546  * @tbl:	Table in which the output is returned.
547  *
548  * This function is called by the protocol drivers to determine the different
549  * clock frequencies supported by serial engine core clock. The protocol
550  * drivers use the output to determine the clock frequency index to be
551  * programmed into DFS.
552  *
553  * Return: number of valid performance levels in the table on success,
554  *	   standard Linux error codes on failure.
555  */
556 int geni_se_clk_tbl_get(struct geni_se *se, unsigned long **tbl)
557 {
558 	long freq = 0;
559 	int i;
560 
561 	if (se->clk_perf_tbl) {
562 		*tbl = se->clk_perf_tbl;
563 		return se->num_clk_levels;
564 	}
565 
566 	se->clk_perf_tbl = devm_kcalloc(se->dev, MAX_CLK_PERF_LEVEL,
567 					sizeof(*se->clk_perf_tbl),
568 					GFP_KERNEL);
569 	if (!se->clk_perf_tbl)
570 		return -ENOMEM;
571 
572 	for (i = 0; i < MAX_CLK_PERF_LEVEL; i++) {
573 		freq = clk_round_rate(se->clk, freq + 1);
574 		if (freq <= 0 || freq == se->clk_perf_tbl[i - 1])
575 			break;
576 		se->clk_perf_tbl[i] = freq;
577 	}
578 	se->num_clk_levels = i;
579 	*tbl = se->clk_perf_tbl;
580 	return se->num_clk_levels;
581 }
582 EXPORT_SYMBOL(geni_se_clk_tbl_get);
583 
584 /**
585  * geni_se_clk_freq_match() - Get the matching or closest SE clock frequency
586  * @se:		Pointer to the concerned serial engine.
587  * @req_freq:	Requested clock frequency.
588  * @index:	Index of the resultant frequency in the table.
589  * @res_freq:	Resultant frequency of the source clock.
590  * @exact:	Flag to indicate exact multiple requirement of the requested
591  *		frequency.
592  *
593  * This function is called by the protocol drivers to determine the best match
594  * of the requested frequency as provided by the serial engine clock in order
595  * to meet the performance requirements.
596  *
597  * If we return success:
598  * - if @exact is true  then @res_freq / <an_integer> == @req_freq
599  * - if @exact is false then @res_freq / <an_integer> <= @req_freq
600  *
601  * Return: 0 on success, standard Linux error codes on failure.
602  */
603 int geni_se_clk_freq_match(struct geni_se *se, unsigned long req_freq,
604 			   unsigned int *index, unsigned long *res_freq,
605 			   bool exact)
606 {
607 	unsigned long *tbl;
608 	int num_clk_levels;
609 	int i;
610 	unsigned long best_delta;
611 	unsigned long new_delta;
612 	unsigned int divider;
613 
614 	num_clk_levels = geni_se_clk_tbl_get(se, &tbl);
615 	if (num_clk_levels < 0)
616 		return num_clk_levels;
617 
618 	if (num_clk_levels == 0)
619 		return -EINVAL;
620 
621 	best_delta = ULONG_MAX;
622 	for (i = 0; i < num_clk_levels; i++) {
623 		divider = DIV_ROUND_UP(tbl[i], req_freq);
624 		new_delta = req_freq - tbl[i] / divider;
625 		if (new_delta < best_delta) {
626 			/* We have a new best! */
627 			*index = i;
628 			*res_freq = tbl[i];
629 
630 			/* If the new best is exact then we're done */
631 			if (new_delta == 0)
632 				return 0;
633 
634 			/* Record how close we got */
635 			best_delta = new_delta;
636 		}
637 	}
638 
639 	if (exact)
640 		return -EINVAL;
641 
642 	return 0;
643 }
644 EXPORT_SYMBOL(geni_se_clk_freq_match);
645 
646 #define GENI_SE_DMA_DONE_EN BIT(0)
647 #define GENI_SE_DMA_EOT_EN BIT(1)
648 #define GENI_SE_DMA_AHB_ERR_EN BIT(2)
649 #define GENI_SE_DMA_EOT_BUF BIT(0)
650 /**
651  * geni_se_tx_dma_prep() - Prepare the serial engine for TX DMA transfer
652  * @se:			Pointer to the concerned serial engine.
653  * @buf:		Pointer to the TX buffer.
654  * @len:		Length of the TX buffer.
655  * @iova:		Pointer to store the mapped DMA address.
656  *
657  * This function is used to prepare the buffers for DMA TX.
658  *
659  * Return: 0 on success, standard Linux error codes on failure.
660  */
661 int geni_se_tx_dma_prep(struct geni_se *se, void *buf, size_t len,
662 			dma_addr_t *iova)
663 {
664 	struct geni_wrapper *wrapper = se->wrapper;
665 	u32 val;
666 
667 	if (!wrapper)
668 		return -EINVAL;
669 
670 	*iova = dma_map_single(wrapper->dev, buf, len, DMA_TO_DEVICE);
671 	if (dma_mapping_error(wrapper->dev, *iova))
672 		return -EIO;
673 
674 	val = GENI_SE_DMA_DONE_EN;
675 	val |= GENI_SE_DMA_EOT_EN;
676 	val |= GENI_SE_DMA_AHB_ERR_EN;
677 	writel_relaxed(val, se->base + SE_DMA_TX_IRQ_EN_SET);
678 	writel_relaxed(lower_32_bits(*iova), se->base + SE_DMA_TX_PTR_L);
679 	writel_relaxed(upper_32_bits(*iova), se->base + SE_DMA_TX_PTR_H);
680 	writel_relaxed(GENI_SE_DMA_EOT_BUF, se->base + SE_DMA_TX_ATTR);
681 	writel(len, se->base + SE_DMA_TX_LEN);
682 	return 0;
683 }
684 EXPORT_SYMBOL(geni_se_tx_dma_prep);
685 
686 /**
687  * geni_se_rx_dma_prep() - Prepare the serial engine for RX DMA transfer
688  * @se:			Pointer to the concerned serial engine.
689  * @buf:		Pointer to the RX buffer.
690  * @len:		Length of the RX buffer.
691  * @iova:		Pointer to store the mapped DMA address.
692  *
693  * This function is used to prepare the buffers for DMA RX.
694  *
695  * Return: 0 on success, standard Linux error codes on failure.
696  */
697 int geni_se_rx_dma_prep(struct geni_se *se, void *buf, size_t len,
698 			dma_addr_t *iova)
699 {
700 	struct geni_wrapper *wrapper = se->wrapper;
701 	u32 val;
702 
703 	if (!wrapper)
704 		return -EINVAL;
705 
706 	*iova = dma_map_single(wrapper->dev, buf, len, DMA_FROM_DEVICE);
707 	if (dma_mapping_error(wrapper->dev, *iova))
708 		return -EIO;
709 
710 	val = GENI_SE_DMA_DONE_EN;
711 	val |= GENI_SE_DMA_EOT_EN;
712 	val |= GENI_SE_DMA_AHB_ERR_EN;
713 	writel_relaxed(val, se->base + SE_DMA_RX_IRQ_EN_SET);
714 	writel_relaxed(lower_32_bits(*iova), se->base + SE_DMA_RX_PTR_L);
715 	writel_relaxed(upper_32_bits(*iova), se->base + SE_DMA_RX_PTR_H);
716 	/* RX does not have EOT buffer type bit. So just reset RX_ATTR */
717 	writel_relaxed(0, se->base + SE_DMA_RX_ATTR);
718 	writel(len, se->base + SE_DMA_RX_LEN);
719 	return 0;
720 }
721 EXPORT_SYMBOL(geni_se_rx_dma_prep);
722 
723 /**
724  * geni_se_tx_dma_unprep() - Unprepare the serial engine after TX DMA transfer
725  * @se:			Pointer to the concerned serial engine.
726  * @iova:		DMA address of the TX buffer.
727  * @len:		Length of the TX buffer.
728  *
729  * This function is used to unprepare the DMA buffers after DMA TX.
730  */
731 void geni_se_tx_dma_unprep(struct geni_se *se, dma_addr_t iova, size_t len)
732 {
733 	struct geni_wrapper *wrapper = se->wrapper;
734 
735 	if (iova && !dma_mapping_error(wrapper->dev, iova))
736 		dma_unmap_single(wrapper->dev, iova, len, DMA_TO_DEVICE);
737 }
738 EXPORT_SYMBOL(geni_se_tx_dma_unprep);
739 
740 /**
741  * geni_se_rx_dma_unprep() - Unprepare the serial engine after RX DMA transfer
742  * @se:			Pointer to the concerned serial engine.
743  * @iova:		DMA address of the RX buffer.
744  * @len:		Length of the RX buffer.
745  *
746  * This function is used to unprepare the DMA buffers after DMA RX.
747  */
748 void geni_se_rx_dma_unprep(struct geni_se *se, dma_addr_t iova, size_t len)
749 {
750 	struct geni_wrapper *wrapper = se->wrapper;
751 
752 	if (iova && !dma_mapping_error(wrapper->dev, iova))
753 		dma_unmap_single(wrapper->dev, iova, len, DMA_FROM_DEVICE);
754 }
755 EXPORT_SYMBOL(geni_se_rx_dma_unprep);
756 
757 int geni_icc_get(struct geni_se *se, const char *icc_ddr)
758 {
759 	int i, err;
760 	const char *icc_names[] = {"qup-core", "qup-config", icc_ddr};
761 
762 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
763 		if (!icc_names[i])
764 			continue;
765 
766 		se->icc_paths[i].path = devm_of_icc_get(se->dev, icc_names[i]);
767 		if (IS_ERR(se->icc_paths[i].path))
768 			goto err;
769 	}
770 
771 	return 0;
772 
773 err:
774 	err = PTR_ERR(se->icc_paths[i].path);
775 	if (err != -EPROBE_DEFER)
776 		dev_err_ratelimited(se->dev, "Failed to get ICC path '%s': %d\n",
777 					icc_names[i], err);
778 	return err;
779 
780 }
781 EXPORT_SYMBOL(geni_icc_get);
782 
783 int geni_icc_set_bw(struct geni_se *se)
784 {
785 	int i, ret;
786 
787 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
788 		ret = icc_set_bw(se->icc_paths[i].path,
789 			se->icc_paths[i].avg_bw, se->icc_paths[i].avg_bw);
790 		if (ret) {
791 			dev_err_ratelimited(se->dev, "ICC BW voting 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_set_bw);
800 
801 void geni_icc_set_tag(struct geni_se *se, u32 tag)
802 {
803 	int i;
804 
805 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++)
806 		icc_set_tag(se->icc_paths[i].path, tag);
807 }
808 EXPORT_SYMBOL(geni_icc_set_tag);
809 
810 /* To do: Replace this by icc_bulk_enable once it's implemented in ICC core */
811 int geni_icc_enable(struct geni_se *se)
812 {
813 	int i, ret;
814 
815 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
816 		ret = icc_enable(se->icc_paths[i].path);
817 		if (ret) {
818 			dev_err_ratelimited(se->dev, "ICC enable failed on path '%s': %d\n",
819 					icc_path_names[i], ret);
820 			return ret;
821 		}
822 	}
823 
824 	return 0;
825 }
826 EXPORT_SYMBOL(geni_icc_enable);
827 
828 int geni_icc_disable(struct geni_se *se)
829 {
830 	int i, ret;
831 
832 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
833 		ret = icc_disable(se->icc_paths[i].path);
834 		if (ret) {
835 			dev_err_ratelimited(se->dev, "ICC disable failed on path '%s': %d\n",
836 					icc_path_names[i], ret);
837 			return ret;
838 		}
839 	}
840 
841 	return 0;
842 }
843 EXPORT_SYMBOL(geni_icc_disable);
844 
845 void geni_remove_earlycon_icc_vote(void)
846 {
847 	struct platform_device *pdev;
848 	struct geni_wrapper *wrapper;
849 	struct device_node *parent;
850 	struct device_node *child;
851 
852 	if (!earlycon_wrapper)
853 		return;
854 
855 	wrapper = earlycon_wrapper;
856 	parent = of_get_next_parent(wrapper->dev->of_node);
857 	for_each_child_of_node(parent, child) {
858 		if (!of_device_is_compatible(child, "qcom,geni-se-qup"))
859 			continue;
860 
861 		pdev = of_find_device_by_node(child);
862 		if (!pdev)
863 			continue;
864 
865 		wrapper = platform_get_drvdata(pdev);
866 		icc_put(wrapper->to_core.path);
867 		wrapper->to_core.path = NULL;
868 
869 	}
870 	of_node_put(parent);
871 
872 	earlycon_wrapper = NULL;
873 }
874 EXPORT_SYMBOL(geni_remove_earlycon_icc_vote);
875 
876 static int geni_se_probe(struct platform_device *pdev)
877 {
878 	struct device *dev = &pdev->dev;
879 	struct resource *res;
880 	struct geni_wrapper *wrapper;
881 	struct console __maybe_unused *bcon;
882 	bool __maybe_unused has_earlycon = false;
883 	int ret;
884 
885 	wrapper = devm_kzalloc(dev, sizeof(*wrapper), GFP_KERNEL);
886 	if (!wrapper)
887 		return -ENOMEM;
888 
889 	wrapper->dev = dev;
890 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
891 	wrapper->base = devm_ioremap_resource(dev, res);
892 	if (IS_ERR(wrapper->base))
893 		return PTR_ERR(wrapper->base);
894 
895 	if (!has_acpi_companion(&pdev->dev)) {
896 		wrapper->ahb_clks[0].id = "m-ahb";
897 		wrapper->ahb_clks[1].id = "s-ahb";
898 		ret = devm_clk_bulk_get(dev, NUM_AHB_CLKS, wrapper->ahb_clks);
899 		if (ret) {
900 			dev_err(dev, "Err getting AHB clks %d\n", ret);
901 			return ret;
902 		}
903 	}
904 
905 #ifdef CONFIG_SERIAL_EARLYCON
906 	for_each_console(bcon) {
907 		if (!strcmp(bcon->name, "qcom_geni")) {
908 			has_earlycon = true;
909 			break;
910 		}
911 	}
912 	if (!has_earlycon)
913 		goto exit;
914 
915 	wrapper->to_core.path = devm_of_icc_get(dev, "qup-core");
916 	if (IS_ERR(wrapper->to_core.path))
917 		return PTR_ERR(wrapper->to_core.path);
918 	/*
919 	 * Put minmal BW request on core clocks on behalf of early console.
920 	 * The vote will be removed earlycon exit function.
921 	 *
922 	 * Note: We are putting vote on each QUP wrapper instead only to which
923 	 * earlycon is connected because QUP core clock of different wrapper
924 	 * share same voltage domain. If core1 is put to 0, then core2 will
925 	 * also run at 0, if not voted. Default ICC vote will be removed ASA
926 	 * we touch any of the core clock.
927 	 * core1 = core2 = max(core1, core2)
928 	 */
929 	ret = icc_set_bw(wrapper->to_core.path, GENI_DEFAULT_BW,
930 				GENI_DEFAULT_BW);
931 	if (ret) {
932 		dev_err(&pdev->dev, "%s: ICC BW voting failed for core: %d\n",
933 			__func__, ret);
934 		return ret;
935 	}
936 
937 	if (of_get_compatible_child(pdev->dev.of_node, "qcom,geni-debug-uart"))
938 		earlycon_wrapper = wrapper;
939 	of_node_put(pdev->dev.of_node);
940 exit:
941 #endif
942 	dev_set_drvdata(dev, wrapper);
943 	dev_dbg(dev, "GENI SE Driver probed\n");
944 	return devm_of_platform_populate(dev);
945 }
946 
947 static const struct of_device_id geni_se_dt_match[] = {
948 	{ .compatible = "qcom,geni-se-qup", },
949 	{}
950 };
951 MODULE_DEVICE_TABLE(of, geni_se_dt_match);
952 
953 static struct platform_driver geni_se_driver = {
954 	.driver = {
955 		.name = "geni_se_qup",
956 		.of_match_table = geni_se_dt_match,
957 	},
958 	.probe = geni_se_probe,
959 };
960 module_platform_driver(geni_se_driver);
961 
962 MODULE_DESCRIPTION("GENI Serial Engine Driver");
963 MODULE_LICENSE("GPL v2");
964