xref: /linux/drivers/soc/qcom/qcom-geni-se.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (c) 2017-2018, The Linux Foundation. All rights reserved.
3 
4 /* Disable MMIO tracing to prevent excessive logging of unwanted MMIO traces */
5 #define __DISABLE_TRACE_MMIO__
6 
7 #include <linux/acpi.h>
8 #include <linux/clk.h>
9 #include <linux/slab.h>
10 #include <linux/dma-mapping.h>
11 #include <linux/io.h>
12 #include <linux/module.h>
13 #include <linux/of.h>
14 #include <linux/of_platform.h>
15 #include <linux/pinctrl/consumer.h>
16 #include <linux/platform_device.h>
17 #include <linux/soc/qcom/geni-se.h>
18 
19 /**
20  * DOC: Overview
21  *
22  * Generic Interface (GENI) Serial Engine (SE) Wrapper driver is introduced
23  * to manage GENI firmware based Qualcomm Universal Peripheral (QUP) Wrapper
24  * controller. QUP Wrapper is designed to support various serial bus protocols
25  * like UART, SPI, I2C, I3C, etc.
26  */
27 
28 /**
29  * DOC: Hardware description
30  *
31  * GENI based QUP is a highly-flexible and programmable module for supporting
32  * a wide range of serial interfaces like UART, SPI, I2C, I3C, etc. A single
33  * QUP module can provide upto 8 serial interfaces, using its internal
34  * serial engines. The actual configuration is determined by the target
35  * platform configuration. The protocol supported by each interface is
36  * determined by the firmware loaded to the serial engine. Each SE consists
37  * of a DMA Engine and GENI sub modules which enable serial engines to
38  * support FIFO and DMA modes of operation.
39  *
40  *
41  *                      +-----------------------------------------+
42  *                      |QUP Wrapper                              |
43  *                      |         +----------------------------+  |
44  *   --QUP & SE Clocks-->         | Serial Engine N            |  +-IO------>
45  *                      |         | ...                        |  | Interface
46  *   <---Clock Perf.----+    +----+-----------------------+    |  |
47  *     State Interface  |    | Serial Engine 1            |    |  |
48  *                      |    |                            |    |  |
49  *                      |    |                            |    |  |
50  *   <--------AHB------->    |                            |    |  |
51  *                      |    |                            +----+  |
52  *                      |    |                            |       |
53  *                      |    |                            |       |
54  *   <------SE IRQ------+    +----------------------------+       |
55  *                      |                                         |
56  *                      +-----------------------------------------+
57  *
58  *                         Figure 1: GENI based QUP Wrapper
59  *
60  * The GENI submodules include primary and secondary sequencers which are
61  * used to drive TX & RX operations. On serial interfaces that operate using
62  * master-slave model, primary sequencer drives both TX & RX operations. On
63  * serial interfaces that operate using peer-to-peer model, primary sequencer
64  * drives TX operation and secondary sequencer drives RX operation.
65  */
66 
67 /**
68  * DOC: Software description
69  *
70  * GENI SE Wrapper driver is structured into 2 parts:
71  *
72  * geni_wrapper represents QUP Wrapper controller. This part of the driver
73  * manages QUP Wrapper information such as hardware version, clock
74  * performance table that is common to all the internal serial engines.
75  *
76  * geni_se represents serial engine. This part of the driver manages serial
77  * engine information such as clocks, containing QUP Wrapper, etc. This part
78  * of driver also supports operations (eg. initialize the concerned serial
79  * engine, select between FIFO and DMA mode of operation etc.) that are
80  * common to all the serial engines and are independent of serial interfaces.
81  */
82 
83 #define MAX_CLK_PERF_LEVEL 32
84 #define MAX_CLKS 2
85 
86 /**
87  * struct geni_wrapper - Data structure to represent the QUP Wrapper Core
88  * @dev:		Device pointer of the QUP wrapper core
89  * @base:		Base address of this instance of QUP wrapper core
90  * @clks:		Handle to the primary & optional secondary AHB clocks
91  * @num_clks:		Count of clocks
92  */
93 struct geni_wrapper {
94 	struct device *dev;
95 	void __iomem *base;
96 	struct clk_bulk_data clks[MAX_CLKS];
97 	unsigned int num_clks;
98 };
99 
100 /**
101  * struct geni_se_desc - Data structure to represent the QUP Wrapper resources
102  * @clks:		Name of the primary & optional secondary AHB clocks
103  * @num_clks:		Count of clock names
104  */
105 struct geni_se_desc {
106 	unsigned int num_clks;
107 	const char * const *clks;
108 };
109 
110 static const char * const icc_path_names[] = {"qup-core", "qup-config",
111 						"qup-memory"};
112 
113 #define QUP_HW_VER_REG			0x4
114 
115 /* Common SE registers */
116 #define GENI_INIT_CFG_REVISION		0x0
117 #define GENI_S_INIT_CFG_REVISION	0x4
118 #define GENI_OUTPUT_CTRL		0x24
119 #define GENI_CGC_CTRL			0x28
120 #define GENI_CLK_CTRL_RO		0x60
121 #define GENI_FW_S_REVISION_RO		0x6c
122 #define SE_GENI_BYTE_GRAN		0x254
123 #define SE_GENI_TX_PACKING_CFG0		0x260
124 #define SE_GENI_TX_PACKING_CFG1		0x264
125 #define SE_GENI_RX_PACKING_CFG0		0x284
126 #define SE_GENI_RX_PACKING_CFG1		0x288
127 #define SE_GENI_M_GP_LENGTH		0x910
128 #define SE_GENI_S_GP_LENGTH		0x914
129 #define SE_DMA_TX_PTR_L			0xc30
130 #define SE_DMA_TX_PTR_H			0xc34
131 #define SE_DMA_TX_ATTR			0xc38
132 #define SE_DMA_TX_LEN			0xc3c
133 #define SE_DMA_TX_IRQ_EN		0xc48
134 #define SE_DMA_TX_IRQ_EN_SET		0xc4c
135 #define SE_DMA_TX_IRQ_EN_CLR		0xc50
136 #define SE_DMA_TX_LEN_IN		0xc54
137 #define SE_DMA_TX_MAX_BURST		0xc5c
138 #define SE_DMA_RX_PTR_L			0xd30
139 #define SE_DMA_RX_PTR_H			0xd34
140 #define SE_DMA_RX_ATTR			0xd38
141 #define SE_DMA_RX_LEN			0xd3c
142 #define SE_DMA_RX_IRQ_EN		0xd48
143 #define SE_DMA_RX_IRQ_EN_SET		0xd4c
144 #define SE_DMA_RX_IRQ_EN_CLR		0xd50
145 #define SE_DMA_RX_LEN_IN		0xd54
146 #define SE_DMA_RX_MAX_BURST		0xd5c
147 #define SE_DMA_RX_FLUSH			0xd60
148 #define SE_GSI_EVENT_EN			0xe18
149 #define SE_IRQ_EN			0xe1c
150 #define SE_DMA_GENERAL_CFG		0xe30
151 
152 /* GENI_OUTPUT_CTRL fields */
153 #define DEFAULT_IO_OUTPUT_CTRL_MSK	GENMASK(6, 0)
154 
155 /* GENI_CGC_CTRL fields */
156 #define CFG_AHB_CLK_CGC_ON		BIT(0)
157 #define CFG_AHB_WR_ACLK_CGC_ON		BIT(1)
158 #define DATA_AHB_CLK_CGC_ON		BIT(2)
159 #define SCLK_CGC_ON			BIT(3)
160 #define TX_CLK_CGC_ON			BIT(4)
161 #define RX_CLK_CGC_ON			BIT(5)
162 #define EXT_CLK_CGC_ON			BIT(6)
163 #define PROG_RAM_HCLK_OFF		BIT(8)
164 #define PROG_RAM_SCLK_OFF		BIT(9)
165 #define DEFAULT_CGC_EN			GENMASK(6, 0)
166 
167 /* SE_GSI_EVENT_EN fields */
168 #define DMA_RX_EVENT_EN			BIT(0)
169 #define DMA_TX_EVENT_EN			BIT(1)
170 #define GENI_M_EVENT_EN			BIT(2)
171 #define GENI_S_EVENT_EN			BIT(3)
172 
173 /* SE_IRQ_EN fields */
174 #define DMA_RX_IRQ_EN			BIT(0)
175 #define DMA_TX_IRQ_EN			BIT(1)
176 #define GENI_M_IRQ_EN			BIT(2)
177 #define GENI_S_IRQ_EN			BIT(3)
178 
179 /* SE_DMA_GENERAL_CFG */
180 #define DMA_RX_CLK_CGC_ON		BIT(0)
181 #define DMA_TX_CLK_CGC_ON		BIT(1)
182 #define DMA_AHB_SLV_CFG_ON		BIT(2)
183 #define AHB_SEC_SLV_CLK_CGC_ON		BIT(3)
184 #define DUMMY_RX_NON_BUFFERABLE		BIT(4)
185 #define RX_DMA_ZERO_PADDING_EN		BIT(5)
186 #define RX_DMA_IRQ_DELAY_MSK		GENMASK(8, 6)
187 #define RX_DMA_IRQ_DELAY_SHFT		6
188 
189 /**
190  * geni_se_get_qup_hw_version() - Read the QUP wrapper Hardware version
191  * @se:	Pointer to the corresponding serial engine.
192  *
193  * Return: Hardware Version of the wrapper.
194  */
195 u32 geni_se_get_qup_hw_version(struct geni_se *se)
196 {
197 	struct geni_wrapper *wrapper = se->wrapper;
198 
199 	return readl_relaxed(wrapper->base + QUP_HW_VER_REG);
200 }
201 EXPORT_SYMBOL_GPL(geni_se_get_qup_hw_version);
202 
203 static void geni_se_io_set_mode(void __iomem *base)
204 {
205 	u32 val;
206 
207 	val = readl_relaxed(base + SE_IRQ_EN);
208 	val |= GENI_M_IRQ_EN | GENI_S_IRQ_EN;
209 	val |= DMA_TX_IRQ_EN | DMA_RX_IRQ_EN;
210 	writel_relaxed(val, base + SE_IRQ_EN);
211 
212 	val = readl_relaxed(base + SE_GENI_DMA_MODE_EN);
213 	val &= ~GENI_DMA_MODE_EN;
214 	writel_relaxed(val, base + SE_GENI_DMA_MODE_EN);
215 
216 	writel_relaxed(0, base + SE_GSI_EVENT_EN);
217 }
218 
219 static void geni_se_io_init(void __iomem *base)
220 {
221 	u32 val;
222 
223 	val = readl_relaxed(base + GENI_CGC_CTRL);
224 	val |= DEFAULT_CGC_EN;
225 	writel_relaxed(val, base + GENI_CGC_CTRL);
226 
227 	val = readl_relaxed(base + SE_DMA_GENERAL_CFG);
228 	val |= AHB_SEC_SLV_CLK_CGC_ON | DMA_AHB_SLV_CFG_ON;
229 	val |= DMA_TX_CLK_CGC_ON | DMA_RX_CLK_CGC_ON;
230 	writel_relaxed(val, base + SE_DMA_GENERAL_CFG);
231 
232 	writel_relaxed(DEFAULT_IO_OUTPUT_CTRL_MSK, base + GENI_OUTPUT_CTRL);
233 	writel_relaxed(FORCE_DEFAULT, base + GENI_FORCE_DEFAULT_REG);
234 }
235 
236 static void geni_se_irq_clear(struct geni_se *se)
237 {
238 	writel_relaxed(0, se->base + SE_GSI_EVENT_EN);
239 	writel_relaxed(0xffffffff, se->base + SE_GENI_M_IRQ_CLEAR);
240 	writel_relaxed(0xffffffff, se->base + SE_GENI_S_IRQ_CLEAR);
241 	writel_relaxed(0xffffffff, se->base + SE_DMA_TX_IRQ_CLR);
242 	writel_relaxed(0xffffffff, se->base + SE_DMA_RX_IRQ_CLR);
243 	writel_relaxed(0xffffffff, se->base + SE_IRQ_EN);
244 }
245 
246 /**
247  * geni_se_init() - Initialize the GENI serial engine
248  * @se:		Pointer to the concerned serial engine.
249  * @rx_wm:	Receive watermark, in units of FIFO words.
250  * @rx_rfr:	Ready-for-receive watermark, in units of FIFO words.
251  *
252  * This function is used to initialize the GENI serial engine, configure
253  * receive watermark and ready-for-receive watermarks.
254  */
255 void geni_se_init(struct geni_se *se, u32 rx_wm, u32 rx_rfr)
256 {
257 	u32 val;
258 
259 	geni_se_irq_clear(se);
260 	geni_se_io_init(se->base);
261 	geni_se_io_set_mode(se->base);
262 
263 	writel_relaxed(rx_wm, se->base + SE_GENI_RX_WATERMARK_REG);
264 	writel_relaxed(rx_rfr, se->base + SE_GENI_RX_RFR_WATERMARK_REG);
265 
266 	val = readl_relaxed(se->base + SE_GENI_M_IRQ_EN);
267 	val |= M_COMMON_GENI_M_IRQ_EN;
268 	writel_relaxed(val, se->base + SE_GENI_M_IRQ_EN);
269 
270 	val = readl_relaxed(se->base + SE_GENI_S_IRQ_EN);
271 	val |= S_COMMON_GENI_S_IRQ_EN;
272 	writel_relaxed(val, se->base + SE_GENI_S_IRQ_EN);
273 }
274 EXPORT_SYMBOL_GPL(geni_se_init);
275 
276 static void geni_se_select_fifo_mode(struct geni_se *se)
277 {
278 	u32 proto = geni_se_read_proto(se);
279 	u32 val, val_old;
280 
281 	geni_se_irq_clear(se);
282 
283 	/* UART driver manages enabling / disabling interrupts internally */
284 	if (proto != GENI_SE_UART) {
285 		/* Non-UART use only primary sequencer so dont bother about S_IRQ */
286 		val_old = val = readl_relaxed(se->base + SE_GENI_M_IRQ_EN);
287 		val |= M_CMD_DONE_EN | M_TX_FIFO_WATERMARK_EN;
288 		val |= M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN;
289 		if (val != val_old)
290 			writel_relaxed(val, se->base + SE_GENI_M_IRQ_EN);
291 	}
292 
293 	val_old = val = readl_relaxed(se->base + SE_GENI_DMA_MODE_EN);
294 	val &= ~GENI_DMA_MODE_EN;
295 	if (val != val_old)
296 		writel_relaxed(val, se->base + SE_GENI_DMA_MODE_EN);
297 }
298 
299 static void geni_se_select_dma_mode(struct geni_se *se)
300 {
301 	u32 proto = geni_se_read_proto(se);
302 	u32 val, val_old;
303 
304 	geni_se_irq_clear(se);
305 
306 	/* UART driver manages enabling / disabling interrupts internally */
307 	if (proto != GENI_SE_UART) {
308 		/* Non-UART use only primary sequencer so dont bother about S_IRQ */
309 		val_old = val = readl_relaxed(se->base + SE_GENI_M_IRQ_EN);
310 		val &= ~(M_CMD_DONE_EN | M_TX_FIFO_WATERMARK_EN);
311 		val &= ~(M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN);
312 		if (val != val_old)
313 			writel_relaxed(val, se->base + SE_GENI_M_IRQ_EN);
314 	}
315 
316 	val_old = val = readl_relaxed(se->base + SE_GENI_DMA_MODE_EN);
317 	val |= GENI_DMA_MODE_EN;
318 	if (val != val_old)
319 		writel_relaxed(val, se->base + SE_GENI_DMA_MODE_EN);
320 }
321 
322 static void geni_se_select_gpi_mode(struct geni_se *se)
323 {
324 	u32 val;
325 
326 	geni_se_irq_clear(se);
327 
328 	writel(0, se->base + SE_IRQ_EN);
329 
330 	val = readl(se->base + SE_GENI_M_IRQ_EN);
331 	val &= ~(M_CMD_DONE_EN | M_TX_FIFO_WATERMARK_EN |
332 		 M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN);
333 	writel(val, se->base + SE_GENI_M_IRQ_EN);
334 
335 	writel(GENI_DMA_MODE_EN, se->base + SE_GENI_DMA_MODE_EN);
336 
337 	val = readl(se->base + SE_GSI_EVENT_EN);
338 	val |= (DMA_RX_EVENT_EN | DMA_TX_EVENT_EN | GENI_M_EVENT_EN | GENI_S_EVENT_EN);
339 	writel(val, se->base + SE_GSI_EVENT_EN);
340 }
341 
342 /**
343  * geni_se_select_mode() - Select the serial engine transfer mode
344  * @se:		Pointer to the concerned serial engine.
345  * @mode:	Transfer mode to be selected.
346  */
347 void geni_se_select_mode(struct geni_se *se, enum geni_se_xfer_mode mode)
348 {
349 	WARN_ON(mode != GENI_SE_FIFO && mode != GENI_SE_DMA && mode != GENI_GPI_DMA);
350 
351 	switch (mode) {
352 	case GENI_SE_FIFO:
353 		geni_se_select_fifo_mode(se);
354 		break;
355 	case GENI_SE_DMA:
356 		geni_se_select_dma_mode(se);
357 		break;
358 	case GENI_GPI_DMA:
359 		geni_se_select_gpi_mode(se);
360 		break;
361 	case GENI_SE_INVALID:
362 	default:
363 		break;
364 	}
365 }
366 EXPORT_SYMBOL_GPL(geni_se_select_mode);
367 
368 /**
369  * DOC: Overview
370  *
371  * GENI FIFO packing is highly configurable. TX/RX packing/unpacking consist
372  * of up to 4 operations, each operation represented by 4 configuration vectors
373  * of 10 bits programmed in GENI_TX_PACKING_CFG0 and GENI_TX_PACKING_CFG1 for
374  * TX FIFO and in GENI_RX_PACKING_CFG0 and GENI_RX_PACKING_CFG1 for RX FIFO.
375  * Refer to below examples for detailed bit-field description.
376  *
377  * Example 1: word_size = 7, packing_mode = 4 x 8, msb_to_lsb = 1
378  *
379  *        +-----------+-------+-------+-------+-------+
380  *        |           | vec_0 | vec_1 | vec_2 | vec_3 |
381  *        +-----------+-------+-------+-------+-------+
382  *        | start     | 0x6   | 0xe   | 0x16  | 0x1e  |
383  *        | direction | 1     | 1     | 1     | 1     |
384  *        | length    | 6     | 6     | 6     | 6     |
385  *        | stop      | 0     | 0     | 0     | 1     |
386  *        +-----------+-------+-------+-------+-------+
387  *
388  * Example 2: word_size = 15, packing_mode = 2 x 16, msb_to_lsb = 0
389  *
390  *        +-----------+-------+-------+-------+-------+
391  *        |           | vec_0 | vec_1 | vec_2 | vec_3 |
392  *        +-----------+-------+-------+-------+-------+
393  *        | start     | 0x0   | 0x8   | 0x10  | 0x18  |
394  *        | direction | 0     | 0     | 0     | 0     |
395  *        | length    | 7     | 6     | 7     | 6     |
396  *        | stop      | 0     | 0     | 0     | 1     |
397  *        +-----------+-------+-------+-------+-------+
398  *
399  * Example 3: word_size = 23, packing_mode = 1 x 32, msb_to_lsb = 1
400  *
401  *        +-----------+-------+-------+-------+-------+
402  *        |           | vec_0 | vec_1 | vec_2 | vec_3 |
403  *        +-----------+-------+-------+-------+-------+
404  *        | start     | 0x16  | 0xe   | 0x6   | 0x0   |
405  *        | direction | 1     | 1     | 1     | 1     |
406  *        | length    | 7     | 7     | 6     | 0     |
407  *        | stop      | 0     | 0     | 1     | 0     |
408  *        +-----------+-------+-------+-------+-------+
409  *
410  */
411 
412 #define NUM_PACKING_VECTORS 4
413 #define PACKING_START_SHIFT 5
414 #define PACKING_DIR_SHIFT 4
415 #define PACKING_LEN_SHIFT 1
416 #define PACKING_STOP_BIT BIT(0)
417 #define PACKING_VECTOR_SHIFT 10
418 /**
419  * geni_se_config_packing() - Packing configuration of the serial engine
420  * @se:		Pointer to the concerned serial engine
421  * @bpw:	Bits of data per transfer word.
422  * @pack_words:	Number of words per fifo element.
423  * @msb_to_lsb:	Transfer from MSB to LSB or vice-versa.
424  * @tx_cfg:	Flag to configure the TX Packing.
425  * @rx_cfg:	Flag to configure the RX Packing.
426  *
427  * This function is used to configure the packing rules for the current
428  * transfer.
429  */
430 void geni_se_config_packing(struct geni_se *se, int bpw, int pack_words,
431 			    bool msb_to_lsb, bool tx_cfg, bool rx_cfg)
432 {
433 	u32 cfg0, cfg1, cfg[NUM_PACKING_VECTORS] = {0};
434 	int len;
435 	int temp_bpw = bpw;
436 	int idx_start = msb_to_lsb ? bpw - 1 : 0;
437 	int idx = idx_start;
438 	int idx_delta = msb_to_lsb ? -BITS_PER_BYTE : BITS_PER_BYTE;
439 	int ceil_bpw = ALIGN(bpw, BITS_PER_BYTE);
440 	int iter = (ceil_bpw * pack_words) / BITS_PER_BYTE;
441 	int i;
442 
443 	if (iter <= 0 || iter > NUM_PACKING_VECTORS)
444 		return;
445 
446 	for (i = 0; i < iter; i++) {
447 		len = min_t(int, temp_bpw, BITS_PER_BYTE) - 1;
448 		cfg[i] = idx << PACKING_START_SHIFT;
449 		cfg[i] |= msb_to_lsb << PACKING_DIR_SHIFT;
450 		cfg[i] |= len << PACKING_LEN_SHIFT;
451 
452 		if (temp_bpw <= BITS_PER_BYTE) {
453 			idx = ((i + 1) * BITS_PER_BYTE) + idx_start;
454 			temp_bpw = bpw;
455 		} else {
456 			idx = idx + idx_delta;
457 			temp_bpw = temp_bpw - BITS_PER_BYTE;
458 		}
459 	}
460 	cfg[iter - 1] |= PACKING_STOP_BIT;
461 	cfg0 = cfg[0] | (cfg[1] << PACKING_VECTOR_SHIFT);
462 	cfg1 = cfg[2] | (cfg[3] << PACKING_VECTOR_SHIFT);
463 
464 	if (tx_cfg) {
465 		writel_relaxed(cfg0, se->base + SE_GENI_TX_PACKING_CFG0);
466 		writel_relaxed(cfg1, se->base + SE_GENI_TX_PACKING_CFG1);
467 	}
468 	if (rx_cfg) {
469 		writel_relaxed(cfg0, se->base + SE_GENI_RX_PACKING_CFG0);
470 		writel_relaxed(cfg1, se->base + SE_GENI_RX_PACKING_CFG1);
471 	}
472 
473 	/*
474 	 * Number of protocol words in each FIFO entry
475 	 * 0 - 4x8, four words in each entry, max word size of 8 bits
476 	 * 1 - 2x16, two words in each entry, max word size of 16 bits
477 	 * 2 - 1x32, one word in each entry, max word size of 32 bits
478 	 * 3 - undefined
479 	 */
480 	if (pack_words || bpw == 32)
481 		writel_relaxed(bpw / 16, se->base + SE_GENI_BYTE_GRAN);
482 }
483 EXPORT_SYMBOL_GPL(geni_se_config_packing);
484 
485 static void geni_se_clks_off(struct geni_se *se)
486 {
487 	struct geni_wrapper *wrapper = se->wrapper;
488 
489 	clk_disable_unprepare(se->clk);
490 	clk_bulk_disable_unprepare(wrapper->num_clks, wrapper->clks);
491 }
492 
493 /**
494  * geni_se_resources_off() - Turn off resources associated with the serial
495  *                           engine
496  * @se:	Pointer to the concerned serial engine.
497  *
498  * Return: 0 on success, standard Linux error codes on failure/error.
499  */
500 int geni_se_resources_off(struct geni_se *se)
501 {
502 	int ret;
503 
504 	if (has_acpi_companion(se->dev))
505 		return 0;
506 
507 	ret = pinctrl_pm_select_sleep_state(se->dev);
508 	if (ret)
509 		return ret;
510 
511 	geni_se_clks_off(se);
512 	return 0;
513 }
514 EXPORT_SYMBOL_GPL(geni_se_resources_off);
515 
516 static int geni_se_clks_on(struct geni_se *se)
517 {
518 	int ret;
519 	struct geni_wrapper *wrapper = se->wrapper;
520 
521 	ret = clk_bulk_prepare_enable(wrapper->num_clks, wrapper->clks);
522 	if (ret)
523 		return ret;
524 
525 	ret = clk_prepare_enable(se->clk);
526 	if (ret)
527 		clk_bulk_disable_unprepare(wrapper->num_clks, wrapper->clks);
528 	return ret;
529 }
530 
531 /**
532  * geni_se_resources_on() - Turn on resources associated with the serial
533  *                          engine
534  * @se:	Pointer to the concerned serial engine.
535  *
536  * Return: 0 on success, standard Linux error codes on failure/error.
537  */
538 int geni_se_resources_on(struct geni_se *se)
539 {
540 	int ret;
541 
542 	if (has_acpi_companion(se->dev))
543 		return 0;
544 
545 	ret = geni_se_clks_on(se);
546 	if (ret)
547 		return ret;
548 
549 	ret = pinctrl_pm_select_default_state(se->dev);
550 	if (ret)
551 		geni_se_clks_off(se);
552 
553 	return ret;
554 }
555 EXPORT_SYMBOL_GPL(geni_se_resources_on);
556 
557 /**
558  * geni_se_clk_tbl_get() - Get the clock table to program DFS
559  * @se:		Pointer to the concerned serial engine.
560  * @tbl:	Table in which the output is returned.
561  *
562  * This function is called by the protocol drivers to determine the different
563  * clock frequencies supported by serial engine core clock. The protocol
564  * drivers use the output to determine the clock frequency index to be
565  * programmed into DFS.
566  *
567  * Return: number of valid performance levels in the table on success,
568  *	   standard Linux error codes on failure.
569  */
570 int geni_se_clk_tbl_get(struct geni_se *se, unsigned long **tbl)
571 {
572 	long freq = 0;
573 	int i;
574 
575 	if (se->clk_perf_tbl) {
576 		*tbl = se->clk_perf_tbl;
577 		return se->num_clk_levels;
578 	}
579 
580 	se->clk_perf_tbl = devm_kcalloc(se->dev, MAX_CLK_PERF_LEVEL,
581 					sizeof(*se->clk_perf_tbl),
582 					GFP_KERNEL);
583 	if (!se->clk_perf_tbl)
584 		return -ENOMEM;
585 
586 	for (i = 0; i < MAX_CLK_PERF_LEVEL; i++) {
587 		freq = clk_round_rate(se->clk, freq + 1);
588 		if (freq <= 0 || freq == se->clk_perf_tbl[i - 1])
589 			break;
590 		se->clk_perf_tbl[i] = freq;
591 	}
592 	se->num_clk_levels = i;
593 	*tbl = se->clk_perf_tbl;
594 	return se->num_clk_levels;
595 }
596 EXPORT_SYMBOL_GPL(geni_se_clk_tbl_get);
597 
598 /**
599  * geni_se_clk_freq_match() - Get the matching or closest SE clock frequency
600  * @se:		Pointer to the concerned serial engine.
601  * @req_freq:	Requested clock frequency.
602  * @index:	Index of the resultant frequency in the table.
603  * @res_freq:	Resultant frequency of the source clock.
604  * @exact:	Flag to indicate exact multiple requirement of the requested
605  *		frequency.
606  *
607  * This function is called by the protocol drivers to determine the best match
608  * of the requested frequency as provided by the serial engine clock in order
609  * to meet the performance requirements.
610  *
611  * If we return success:
612  * - if @exact is true  then @res_freq / <an_integer> == @req_freq
613  * - if @exact is false then @res_freq / <an_integer> <= @req_freq
614  *
615  * Return: 0 on success, standard Linux error codes on failure.
616  */
617 int geni_se_clk_freq_match(struct geni_se *se, unsigned long req_freq,
618 			   unsigned int *index, unsigned long *res_freq,
619 			   bool exact)
620 {
621 	unsigned long *tbl;
622 	int num_clk_levels;
623 	int i;
624 	unsigned long best_delta;
625 	unsigned long new_delta;
626 	unsigned int divider;
627 
628 	num_clk_levels = geni_se_clk_tbl_get(se, &tbl);
629 	if (num_clk_levels < 0)
630 		return num_clk_levels;
631 
632 	if (num_clk_levels == 0)
633 		return -EINVAL;
634 
635 	best_delta = ULONG_MAX;
636 	for (i = 0; i < num_clk_levels; i++) {
637 		divider = DIV_ROUND_UP(tbl[i], req_freq);
638 		new_delta = req_freq - tbl[i] / divider;
639 		if (new_delta < best_delta) {
640 			/* We have a new best! */
641 			*index = i;
642 			*res_freq = tbl[i];
643 
644 			/* If the new best is exact then we're done */
645 			if (new_delta == 0)
646 				return 0;
647 
648 			/* Record how close we got */
649 			best_delta = new_delta;
650 		}
651 	}
652 
653 	if (exact)
654 		return -EINVAL;
655 
656 	return 0;
657 }
658 EXPORT_SYMBOL_GPL(geni_se_clk_freq_match);
659 
660 #define GENI_SE_DMA_DONE_EN BIT(0)
661 #define GENI_SE_DMA_EOT_EN BIT(1)
662 #define GENI_SE_DMA_AHB_ERR_EN BIT(2)
663 #define GENI_SE_DMA_EOT_BUF BIT(0)
664 
665 /**
666  * geni_se_tx_init_dma() - Initiate TX DMA transfer on the serial engine
667  * @se:			Pointer to the concerned serial engine.
668  * @iova:		Mapped DMA address.
669  * @len:		Length of the TX buffer.
670  *
671  * This function is used to initiate DMA TX transfer.
672  */
673 void geni_se_tx_init_dma(struct geni_se *se, dma_addr_t iova, size_t len)
674 {
675 	u32 val;
676 
677 	val = GENI_SE_DMA_DONE_EN;
678 	val |= GENI_SE_DMA_EOT_EN;
679 	val |= GENI_SE_DMA_AHB_ERR_EN;
680 	writel_relaxed(val, se->base + SE_DMA_TX_IRQ_EN_SET);
681 	writel_relaxed(lower_32_bits(iova), se->base + SE_DMA_TX_PTR_L);
682 	writel_relaxed(upper_32_bits(iova), se->base + SE_DMA_TX_PTR_H);
683 	writel_relaxed(GENI_SE_DMA_EOT_BUF, se->base + SE_DMA_TX_ATTR);
684 	writel(len, se->base + SE_DMA_TX_LEN);
685 }
686 EXPORT_SYMBOL_GPL(geni_se_tx_init_dma);
687 
688 /**
689  * geni_se_tx_dma_prep() - Prepare the serial engine for TX DMA transfer
690  * @se:			Pointer to the concerned serial engine.
691  * @buf:		Pointer to the TX buffer.
692  * @len:		Length of the TX buffer.
693  * @iova:		Pointer to store the mapped DMA address.
694  *
695  * This function is used to prepare the buffers for DMA TX.
696  *
697  * Return: 0 on success, standard Linux error codes on failure.
698  */
699 int geni_se_tx_dma_prep(struct geni_se *se, void *buf, size_t len,
700 			dma_addr_t *iova)
701 {
702 	struct geni_wrapper *wrapper = se->wrapper;
703 
704 	if (!wrapper)
705 		return -EINVAL;
706 
707 	*iova = dma_map_single(wrapper->dev, buf, len, DMA_TO_DEVICE);
708 	if (dma_mapping_error(wrapper->dev, *iova))
709 		return -EIO;
710 
711 	geni_se_tx_init_dma(se, *iova, len);
712 	return 0;
713 }
714 EXPORT_SYMBOL_GPL(geni_se_tx_dma_prep);
715 
716 /**
717  * geni_se_rx_init_dma() - Initiate RX DMA transfer on the serial engine
718  * @se:			Pointer to the concerned serial engine.
719  * @iova:		Mapped DMA address.
720  * @len:		Length of the RX buffer.
721  *
722  * This function is used to initiate DMA RX transfer.
723  */
724 void geni_se_rx_init_dma(struct geni_se *se, dma_addr_t iova, size_t len)
725 {
726 	u32 val;
727 
728 	val = GENI_SE_DMA_DONE_EN;
729 	val |= GENI_SE_DMA_EOT_EN;
730 	val |= GENI_SE_DMA_AHB_ERR_EN;
731 	writel_relaxed(val, se->base + SE_DMA_RX_IRQ_EN_SET);
732 	writel_relaxed(lower_32_bits(iova), se->base + SE_DMA_RX_PTR_L);
733 	writel_relaxed(upper_32_bits(iova), se->base + SE_DMA_RX_PTR_H);
734 	/* RX does not have EOT buffer type bit. So just reset RX_ATTR */
735 	writel_relaxed(0, se->base + SE_DMA_RX_ATTR);
736 	writel(len, se->base + SE_DMA_RX_LEN);
737 }
738 EXPORT_SYMBOL_GPL(geni_se_rx_init_dma);
739 
740 /**
741  * geni_se_rx_dma_prep() - Prepare the serial engine for RX DMA transfer
742  * @se:			Pointer to the concerned serial engine.
743  * @buf:		Pointer to the RX buffer.
744  * @len:		Length of the RX buffer.
745  * @iova:		Pointer to store the mapped DMA address.
746  *
747  * This function is used to prepare the buffers for DMA RX.
748  *
749  * Return: 0 on success, standard Linux error codes on failure.
750  */
751 int geni_se_rx_dma_prep(struct geni_se *se, void *buf, size_t len,
752 			dma_addr_t *iova)
753 {
754 	struct geni_wrapper *wrapper = se->wrapper;
755 
756 	if (!wrapper)
757 		return -EINVAL;
758 
759 	*iova = dma_map_single(wrapper->dev, buf, len, DMA_FROM_DEVICE);
760 	if (dma_mapping_error(wrapper->dev, *iova))
761 		return -EIO;
762 
763 	geni_se_rx_init_dma(se, *iova, len);
764 	return 0;
765 }
766 EXPORT_SYMBOL_GPL(geni_se_rx_dma_prep);
767 
768 /**
769  * geni_se_tx_dma_unprep() - Unprepare the serial engine after TX DMA transfer
770  * @se:			Pointer to the concerned serial engine.
771  * @iova:		DMA address of the TX buffer.
772  * @len:		Length of the TX buffer.
773  *
774  * This function is used to unprepare the DMA buffers after DMA TX.
775  */
776 void geni_se_tx_dma_unprep(struct geni_se *se, dma_addr_t iova, size_t len)
777 {
778 	struct geni_wrapper *wrapper = se->wrapper;
779 
780 	if (!dma_mapping_error(wrapper->dev, iova))
781 		dma_unmap_single(wrapper->dev, iova, len, DMA_TO_DEVICE);
782 }
783 EXPORT_SYMBOL_GPL(geni_se_tx_dma_unprep);
784 
785 /**
786  * geni_se_rx_dma_unprep() - Unprepare the serial engine after RX DMA transfer
787  * @se:			Pointer to the concerned serial engine.
788  * @iova:		DMA address of the RX buffer.
789  * @len:		Length of the RX buffer.
790  *
791  * This function is used to unprepare the DMA buffers after DMA RX.
792  */
793 void geni_se_rx_dma_unprep(struct geni_se *se, dma_addr_t iova, size_t len)
794 {
795 	struct geni_wrapper *wrapper = se->wrapper;
796 
797 	if (!dma_mapping_error(wrapper->dev, iova))
798 		dma_unmap_single(wrapper->dev, iova, len, DMA_FROM_DEVICE);
799 }
800 EXPORT_SYMBOL_GPL(geni_se_rx_dma_unprep);
801 
802 int geni_icc_get(struct geni_se *se, const char *icc_ddr)
803 {
804 	int i, err;
805 	const char *icc_names[] = {"qup-core", "qup-config", icc_ddr};
806 
807 	if (has_acpi_companion(se->dev))
808 		return 0;
809 
810 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
811 		if (!icc_names[i])
812 			continue;
813 
814 		se->icc_paths[i].path = devm_of_icc_get(se->dev, icc_names[i]);
815 		if (IS_ERR(se->icc_paths[i].path))
816 			goto err;
817 	}
818 
819 	return 0;
820 
821 err:
822 	err = PTR_ERR(se->icc_paths[i].path);
823 	if (err != -EPROBE_DEFER)
824 		dev_err_ratelimited(se->dev, "Failed to get ICC path '%s': %d\n",
825 					icc_names[i], err);
826 	return err;
827 
828 }
829 EXPORT_SYMBOL_GPL(geni_icc_get);
830 
831 int geni_icc_set_bw(struct geni_se *se)
832 {
833 	int i, ret;
834 
835 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
836 		ret = icc_set_bw(se->icc_paths[i].path,
837 			se->icc_paths[i].avg_bw, se->icc_paths[i].avg_bw);
838 		if (ret) {
839 			dev_err_ratelimited(se->dev, "ICC BW voting failed on path '%s': %d\n",
840 					icc_path_names[i], ret);
841 			return ret;
842 		}
843 	}
844 
845 	return 0;
846 }
847 EXPORT_SYMBOL_GPL(geni_icc_set_bw);
848 
849 void geni_icc_set_tag(struct geni_se *se, u32 tag)
850 {
851 	int i;
852 
853 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++)
854 		icc_set_tag(se->icc_paths[i].path, tag);
855 }
856 EXPORT_SYMBOL_GPL(geni_icc_set_tag);
857 
858 /* To do: Replace this by icc_bulk_enable once it's implemented in ICC core */
859 int geni_icc_enable(struct geni_se *se)
860 {
861 	int i, ret;
862 
863 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
864 		ret = icc_enable(se->icc_paths[i].path);
865 		if (ret) {
866 			dev_err_ratelimited(se->dev, "ICC enable failed on path '%s': %d\n",
867 					icc_path_names[i], ret);
868 			return ret;
869 		}
870 	}
871 
872 	return 0;
873 }
874 EXPORT_SYMBOL_GPL(geni_icc_enable);
875 
876 int geni_icc_disable(struct geni_se *se)
877 {
878 	int i, ret;
879 
880 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
881 		ret = icc_disable(se->icc_paths[i].path);
882 		if (ret) {
883 			dev_err_ratelimited(se->dev, "ICC disable failed on path '%s': %d\n",
884 					icc_path_names[i], ret);
885 			return ret;
886 		}
887 	}
888 
889 	return 0;
890 }
891 EXPORT_SYMBOL_GPL(geni_icc_disable);
892 
893 static int geni_se_probe(struct platform_device *pdev)
894 {
895 	struct device *dev = &pdev->dev;
896 	struct geni_wrapper *wrapper;
897 	int ret;
898 
899 	wrapper = devm_kzalloc(dev, sizeof(*wrapper), GFP_KERNEL);
900 	if (!wrapper)
901 		return -ENOMEM;
902 
903 	wrapper->dev = dev;
904 	wrapper->base = devm_platform_ioremap_resource(pdev, 0);
905 	if (IS_ERR(wrapper->base))
906 		return PTR_ERR(wrapper->base);
907 
908 	if (!has_acpi_companion(&pdev->dev)) {
909 		const struct geni_se_desc *desc;
910 		int i;
911 
912 		desc = device_get_match_data(&pdev->dev);
913 		if (!desc)
914 			return -EINVAL;
915 
916 		wrapper->num_clks = min_t(unsigned int, desc->num_clks, MAX_CLKS);
917 
918 		for (i = 0; i < wrapper->num_clks; ++i)
919 			wrapper->clks[i].id = desc->clks[i];
920 
921 		ret = of_count_phandle_with_args(dev->of_node, "clocks", "#clock-cells");
922 		if (ret < 0) {
923 			dev_err(dev, "invalid clocks property at %pOF\n", dev->of_node);
924 			return ret;
925 		}
926 
927 		if (ret < wrapper->num_clks) {
928 			dev_err(dev, "invalid clocks count at %pOF, expected %d entries\n",
929 				dev->of_node, wrapper->num_clks);
930 			return -EINVAL;
931 		}
932 
933 		ret = devm_clk_bulk_get(dev, wrapper->num_clks, wrapper->clks);
934 		if (ret) {
935 			dev_err(dev, "Err getting clks %d\n", ret);
936 			return ret;
937 		}
938 	}
939 
940 	dev_set_drvdata(dev, wrapper);
941 	dev_dbg(dev, "GENI SE Driver probed\n");
942 	return devm_of_platform_populate(dev);
943 }
944 
945 static const char * const qup_clks[] = {
946 	"m-ahb",
947 	"s-ahb",
948 };
949 
950 static const struct geni_se_desc qup_desc = {
951 	.clks = qup_clks,
952 	.num_clks = ARRAY_SIZE(qup_clks),
953 };
954 
955 static const char * const i2c_master_hub_clks[] = {
956 	"s-ahb",
957 };
958 
959 static const struct geni_se_desc i2c_master_hub_desc = {
960 	.clks = i2c_master_hub_clks,
961 	.num_clks = ARRAY_SIZE(i2c_master_hub_clks),
962 };
963 
964 static const struct of_device_id geni_se_dt_match[] = {
965 	{ .compatible = "qcom,geni-se-qup", .data = &qup_desc },
966 	{ .compatible = "qcom,geni-se-i2c-master-hub", .data = &i2c_master_hub_desc },
967 	{}
968 };
969 MODULE_DEVICE_TABLE(of, geni_se_dt_match);
970 
971 static struct platform_driver geni_se_driver = {
972 	.driver = {
973 		.name = "geni_se_qup",
974 		.of_match_table = geni_se_dt_match,
975 	},
976 	.probe = geni_se_probe,
977 };
978 module_platform_driver(geni_se_driver);
979 
980 MODULE_DESCRIPTION("GENI Serial Engine Driver");
981 MODULE_LICENSE("GPL v2");
982