xref: /openbmc/linux/drivers/soc/qcom/qcom-geni-se.c (revision 89aba575)
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/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 NUM_AHB_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  * @ahb_clks:		Handle to the primary & secondary AHB clocks
91  * @to_core:		Core ICC path
92  */
93 struct geni_wrapper {
94 	struct device *dev;
95 	void __iomem *base;
96 	struct clk_bulk_data ahb_clks[NUM_AHB_CLKS];
97 };
98 
99 static const char * const icc_path_names[] = {"qup-core", "qup-config",
100 						"qup-memory"};
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_FW_S_REVISION_RO		0x6c
111 #define SE_GENI_BYTE_GRAN		0x254
112 #define SE_GENI_TX_PACKING_CFG0		0x260
113 #define SE_GENI_TX_PACKING_CFG1		0x264
114 #define SE_GENI_RX_PACKING_CFG0		0x284
115 #define SE_GENI_RX_PACKING_CFG1		0x288
116 #define SE_GENI_M_GP_LENGTH		0x910
117 #define SE_GENI_S_GP_LENGTH		0x914
118 #define SE_DMA_TX_PTR_L			0xc30
119 #define SE_DMA_TX_PTR_H			0xc34
120 #define SE_DMA_TX_ATTR			0xc38
121 #define SE_DMA_TX_LEN			0xc3c
122 #define SE_DMA_TX_IRQ_EN		0xc48
123 #define SE_DMA_TX_IRQ_EN_SET		0xc4c
124 #define SE_DMA_TX_IRQ_EN_CLR		0xc50
125 #define SE_DMA_TX_LEN_IN		0xc54
126 #define SE_DMA_TX_MAX_BURST		0xc5c
127 #define SE_DMA_RX_PTR_L			0xd30
128 #define SE_DMA_RX_PTR_H			0xd34
129 #define SE_DMA_RX_ATTR			0xd38
130 #define SE_DMA_RX_LEN			0xd3c
131 #define SE_DMA_RX_IRQ_EN		0xd48
132 #define SE_DMA_RX_IRQ_EN_SET		0xd4c
133 #define SE_DMA_RX_IRQ_EN_CLR		0xd50
134 #define SE_DMA_RX_LEN_IN		0xd54
135 #define SE_DMA_RX_MAX_BURST		0xd5c
136 #define SE_DMA_RX_FLUSH			0xd60
137 #define SE_GSI_EVENT_EN			0xe18
138 #define SE_IRQ_EN			0xe1c
139 #define SE_DMA_GENERAL_CFG		0xe30
140 
141 /* GENI_OUTPUT_CTRL fields */
142 #define DEFAULT_IO_OUTPUT_CTRL_MSK	GENMASK(6, 0)
143 
144 /* GENI_CGC_CTRL fields */
145 #define CFG_AHB_CLK_CGC_ON		BIT(0)
146 #define CFG_AHB_WR_ACLK_CGC_ON		BIT(1)
147 #define DATA_AHB_CLK_CGC_ON		BIT(2)
148 #define SCLK_CGC_ON			BIT(3)
149 #define TX_CLK_CGC_ON			BIT(4)
150 #define RX_CLK_CGC_ON			BIT(5)
151 #define EXT_CLK_CGC_ON			BIT(6)
152 #define PROG_RAM_HCLK_OFF		BIT(8)
153 #define PROG_RAM_SCLK_OFF		BIT(9)
154 #define DEFAULT_CGC_EN			GENMASK(6, 0)
155 
156 /* SE_GSI_EVENT_EN fields */
157 #define DMA_RX_EVENT_EN			BIT(0)
158 #define DMA_TX_EVENT_EN			BIT(1)
159 #define GENI_M_EVENT_EN			BIT(2)
160 #define GENI_S_EVENT_EN			BIT(3)
161 
162 /* SE_IRQ_EN fields */
163 #define DMA_RX_IRQ_EN			BIT(0)
164 #define DMA_TX_IRQ_EN			BIT(1)
165 #define GENI_M_IRQ_EN			BIT(2)
166 #define GENI_S_IRQ_EN			BIT(3)
167 
168 /* SE_DMA_GENERAL_CFG */
169 #define DMA_RX_CLK_CGC_ON		BIT(0)
170 #define DMA_TX_CLK_CGC_ON		BIT(1)
171 #define DMA_AHB_SLV_CFG_ON		BIT(2)
172 #define AHB_SEC_SLV_CLK_CGC_ON		BIT(3)
173 #define DUMMY_RX_NON_BUFFERABLE		BIT(4)
174 #define RX_DMA_ZERO_PADDING_EN		BIT(5)
175 #define RX_DMA_IRQ_DELAY_MSK		GENMASK(8, 6)
176 #define RX_DMA_IRQ_DELAY_SHFT		6
177 
178 /**
179  * geni_se_get_qup_hw_version() - Read the QUP wrapper Hardware version
180  * @se:	Pointer to the corresponding serial engine.
181  *
182  * Return: Hardware Version of the wrapper.
183  */
184 u32 geni_se_get_qup_hw_version(struct geni_se *se)
185 {
186 	struct geni_wrapper *wrapper = se->wrapper;
187 
188 	return readl_relaxed(wrapper->base + QUP_HW_VER_REG);
189 }
190 EXPORT_SYMBOL(geni_se_get_qup_hw_version);
191 
192 static void geni_se_io_set_mode(void __iomem *base)
193 {
194 	u32 val;
195 
196 	val = readl_relaxed(base + SE_IRQ_EN);
197 	val |= GENI_M_IRQ_EN | GENI_S_IRQ_EN;
198 	val |= DMA_TX_IRQ_EN | DMA_RX_IRQ_EN;
199 	writel_relaxed(val, base + SE_IRQ_EN);
200 
201 	val = readl_relaxed(base + SE_GENI_DMA_MODE_EN);
202 	val &= ~GENI_DMA_MODE_EN;
203 	writel_relaxed(val, base + SE_GENI_DMA_MODE_EN);
204 
205 	writel_relaxed(0, base + SE_GSI_EVENT_EN);
206 }
207 
208 static void geni_se_io_init(void __iomem *base)
209 {
210 	u32 val;
211 
212 	val = readl_relaxed(base + GENI_CGC_CTRL);
213 	val |= DEFAULT_CGC_EN;
214 	writel_relaxed(val, base + GENI_CGC_CTRL);
215 
216 	val = readl_relaxed(base + SE_DMA_GENERAL_CFG);
217 	val |= AHB_SEC_SLV_CLK_CGC_ON | DMA_AHB_SLV_CFG_ON;
218 	val |= DMA_TX_CLK_CGC_ON | DMA_RX_CLK_CGC_ON;
219 	writel_relaxed(val, base + SE_DMA_GENERAL_CFG);
220 
221 	writel_relaxed(DEFAULT_IO_OUTPUT_CTRL_MSK, base + GENI_OUTPUT_CTRL);
222 	writel_relaxed(FORCE_DEFAULT, base + GENI_FORCE_DEFAULT_REG);
223 }
224 
225 static void geni_se_irq_clear(struct geni_se *se)
226 {
227 	writel_relaxed(0, se->base + SE_GSI_EVENT_EN);
228 	writel_relaxed(0xffffffff, se->base + SE_GENI_M_IRQ_CLEAR);
229 	writel_relaxed(0xffffffff, se->base + SE_GENI_S_IRQ_CLEAR);
230 	writel_relaxed(0xffffffff, se->base + SE_DMA_TX_IRQ_CLR);
231 	writel_relaxed(0xffffffff, se->base + SE_DMA_RX_IRQ_CLR);
232 	writel_relaxed(0xffffffff, se->base + SE_IRQ_EN);
233 }
234 
235 /**
236  * geni_se_init() - Initialize the GENI serial engine
237  * @se:		Pointer to the concerned serial engine.
238  * @rx_wm:	Receive watermark, in units of FIFO words.
239  * @rx_rfr:	Ready-for-receive watermark, in units of FIFO words.
240  *
241  * This function is used to initialize the GENI serial engine, configure
242  * receive watermark and ready-for-receive watermarks.
243  */
244 void geni_se_init(struct geni_se *se, u32 rx_wm, u32 rx_rfr)
245 {
246 	u32 val;
247 
248 	geni_se_irq_clear(se);
249 	geni_se_io_init(se->base);
250 	geni_se_io_set_mode(se->base);
251 
252 	writel_relaxed(rx_wm, se->base + SE_GENI_RX_WATERMARK_REG);
253 	writel_relaxed(rx_rfr, se->base + SE_GENI_RX_RFR_WATERMARK_REG);
254 
255 	val = readl_relaxed(se->base + SE_GENI_M_IRQ_EN);
256 	val |= M_COMMON_GENI_M_IRQ_EN;
257 	writel_relaxed(val, se->base + SE_GENI_M_IRQ_EN);
258 
259 	val = readl_relaxed(se->base + SE_GENI_S_IRQ_EN);
260 	val |= S_COMMON_GENI_S_IRQ_EN;
261 	writel_relaxed(val, se->base + SE_GENI_S_IRQ_EN);
262 }
263 EXPORT_SYMBOL(geni_se_init);
264 
265 static void geni_se_select_fifo_mode(struct geni_se *se)
266 {
267 	u32 proto = geni_se_read_proto(se);
268 	u32 val, val_old;
269 
270 	geni_se_irq_clear(se);
271 
272 	/*
273 	 * The RX path for the UART is asynchronous and so needs more
274 	 * complex logic for enabling / disabling its interrupts.
275 	 *
276 	 * Specific notes:
277 	 * - The done and TX-related interrupts are managed manually.
278 	 * - We don't RX from the main sequencer (we use the secondary) so
279 	 *   we don't need the RX-related interrupts enabled in the main
280 	 *   sequencer for UART.
281 	 */
282 	if (proto != GENI_SE_UART) {
283 		val_old = val = readl_relaxed(se->base + SE_GENI_M_IRQ_EN);
284 		val |= M_CMD_DONE_EN | M_TX_FIFO_WATERMARK_EN;
285 		val |= M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN;
286 		if (val != val_old)
287 			writel_relaxed(val, se->base + SE_GENI_M_IRQ_EN);
288 
289 		val_old = val = readl_relaxed(se->base + SE_GENI_S_IRQ_EN);
290 		val |= S_CMD_DONE_EN;
291 		if (val != val_old)
292 			writel_relaxed(val, se->base + SE_GENI_S_IRQ_EN);
293 	}
294 
295 	val_old = val = readl_relaxed(se->base + SE_GENI_DMA_MODE_EN);
296 	val &= ~GENI_DMA_MODE_EN;
297 	if (val != val_old)
298 		writel_relaxed(val, se->base + SE_GENI_DMA_MODE_EN);
299 }
300 
301 static void geni_se_select_dma_mode(struct geni_se *se)
302 {
303 	u32 proto = geni_se_read_proto(se);
304 	u32 val, val_old;
305 
306 	geni_se_irq_clear(se);
307 
308 	if (proto != GENI_SE_UART) {
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 		val_old = val = readl_relaxed(se->base + SE_GENI_S_IRQ_EN);
316 		val &= ~S_CMD_DONE_EN;
317 		if (val != val_old)
318 			writel_relaxed(val, se->base + SE_GENI_S_IRQ_EN);
319 	}
320 
321 	val_old = val = readl_relaxed(se->base + SE_GENI_DMA_MODE_EN);
322 	val |= GENI_DMA_MODE_EN;
323 	if (val != val_old)
324 		writel_relaxed(val, se->base + SE_GENI_DMA_MODE_EN);
325 }
326 
327 static void geni_se_select_gpi_mode(struct geni_se *se)
328 {
329 	u32 val;
330 
331 	geni_se_irq_clear(se);
332 
333 	writel(0, se->base + SE_IRQ_EN);
334 
335 	val = readl(se->base + SE_GENI_S_IRQ_EN);
336 	val &= ~S_CMD_DONE_EN;
337 	writel(val, se->base + SE_GENI_S_IRQ_EN);
338 
339 	val = readl(se->base + SE_GENI_M_IRQ_EN);
340 	val &= ~(M_CMD_DONE_EN | M_TX_FIFO_WATERMARK_EN |
341 		 M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN);
342 	writel(val, se->base + SE_GENI_M_IRQ_EN);
343 
344 	writel(GENI_DMA_MODE_EN, se->base + SE_GENI_DMA_MODE_EN);
345 
346 	val = readl(se->base + SE_GSI_EVENT_EN);
347 	val |= (DMA_RX_EVENT_EN | DMA_TX_EVENT_EN | GENI_M_EVENT_EN | GENI_S_EVENT_EN);
348 	writel(val, se->base + SE_GSI_EVENT_EN);
349 }
350 
351 /**
352  * geni_se_select_mode() - Select the serial engine transfer mode
353  * @se:		Pointer to the concerned serial engine.
354  * @mode:	Transfer mode to be selected.
355  */
356 void geni_se_select_mode(struct geni_se *se, enum geni_se_xfer_mode mode)
357 {
358 	WARN_ON(mode != GENI_SE_FIFO && mode != GENI_SE_DMA && mode != GENI_GPI_DMA);
359 
360 	switch (mode) {
361 	case GENI_SE_FIFO:
362 		geni_se_select_fifo_mode(se);
363 		break;
364 	case GENI_SE_DMA:
365 		geni_se_select_dma_mode(se);
366 		break;
367 	case GENI_GPI_DMA:
368 		geni_se_select_gpi_mode(se);
369 		break;
370 	case GENI_SE_INVALID:
371 	default:
372 		break;
373 	}
374 }
375 EXPORT_SYMBOL(geni_se_select_mode);
376 
377 /**
378  * DOC: Overview
379  *
380  * GENI FIFO packing is highly configurable. TX/RX packing/unpacking consist
381  * of up to 4 operations, each operation represented by 4 configuration vectors
382  * of 10 bits programmed in GENI_TX_PACKING_CFG0 and GENI_TX_PACKING_CFG1 for
383  * TX FIFO and in GENI_RX_PACKING_CFG0 and GENI_RX_PACKING_CFG1 for RX FIFO.
384  * Refer to below examples for detailed bit-field description.
385  *
386  * Example 1: word_size = 7, packing_mode = 4 x 8, msb_to_lsb = 1
387  *
388  *        +-----------+-------+-------+-------+-------+
389  *        |           | vec_0 | vec_1 | vec_2 | vec_3 |
390  *        +-----------+-------+-------+-------+-------+
391  *        | start     | 0x6   | 0xe   | 0x16  | 0x1e  |
392  *        | direction | 1     | 1     | 1     | 1     |
393  *        | length    | 6     | 6     | 6     | 6     |
394  *        | stop      | 0     | 0     | 0     | 1     |
395  *        +-----------+-------+-------+-------+-------+
396  *
397  * Example 2: word_size = 15, packing_mode = 2 x 16, msb_to_lsb = 0
398  *
399  *        +-----------+-------+-------+-------+-------+
400  *        |           | vec_0 | vec_1 | vec_2 | vec_3 |
401  *        +-----------+-------+-------+-------+-------+
402  *        | start     | 0x0   | 0x8   | 0x10  | 0x18  |
403  *        | direction | 0     | 0     | 0     | 0     |
404  *        | length    | 7     | 6     | 7     | 6     |
405  *        | stop      | 0     | 0     | 0     | 1     |
406  *        +-----------+-------+-------+-------+-------+
407  *
408  * Example 3: word_size = 23, packing_mode = 1 x 32, msb_to_lsb = 1
409  *
410  *        +-----------+-------+-------+-------+-------+
411  *        |           | vec_0 | vec_1 | vec_2 | vec_3 |
412  *        +-----------+-------+-------+-------+-------+
413  *        | start     | 0x16  | 0xe   | 0x6   | 0x0   |
414  *        | direction | 1     | 1     | 1     | 1     |
415  *        | length    | 7     | 7     | 6     | 0     |
416  *        | stop      | 0     | 0     | 1     | 0     |
417  *        +-----------+-------+-------+-------+-------+
418  *
419  */
420 
421 #define NUM_PACKING_VECTORS 4
422 #define PACKING_START_SHIFT 5
423 #define PACKING_DIR_SHIFT 4
424 #define PACKING_LEN_SHIFT 1
425 #define PACKING_STOP_BIT BIT(0)
426 #define PACKING_VECTOR_SHIFT 10
427 /**
428  * geni_se_config_packing() - Packing configuration of the serial engine
429  * @se:		Pointer to the concerned serial engine
430  * @bpw:	Bits of data per transfer word.
431  * @pack_words:	Number of words per fifo element.
432  * @msb_to_lsb:	Transfer from MSB to LSB or vice-versa.
433  * @tx_cfg:	Flag to configure the TX Packing.
434  * @rx_cfg:	Flag to configure the RX Packing.
435  *
436  * This function is used to configure the packing rules for the current
437  * transfer.
438  */
439 void geni_se_config_packing(struct geni_se *se, int bpw, int pack_words,
440 			    bool msb_to_lsb, bool tx_cfg, bool rx_cfg)
441 {
442 	u32 cfg0, cfg1, cfg[NUM_PACKING_VECTORS] = {0};
443 	int len;
444 	int temp_bpw = bpw;
445 	int idx_start = msb_to_lsb ? bpw - 1 : 0;
446 	int idx = idx_start;
447 	int idx_delta = msb_to_lsb ? -BITS_PER_BYTE : BITS_PER_BYTE;
448 	int ceil_bpw = ALIGN(bpw, BITS_PER_BYTE);
449 	int iter = (ceil_bpw * pack_words) / BITS_PER_BYTE;
450 	int i;
451 
452 	if (iter <= 0 || iter > NUM_PACKING_VECTORS)
453 		return;
454 
455 	for (i = 0; i < iter; i++) {
456 		len = min_t(int, temp_bpw, BITS_PER_BYTE) - 1;
457 		cfg[i] = idx << PACKING_START_SHIFT;
458 		cfg[i] |= msb_to_lsb << PACKING_DIR_SHIFT;
459 		cfg[i] |= len << PACKING_LEN_SHIFT;
460 
461 		if (temp_bpw <= BITS_PER_BYTE) {
462 			idx = ((i + 1) * BITS_PER_BYTE) + idx_start;
463 			temp_bpw = bpw;
464 		} else {
465 			idx = idx + idx_delta;
466 			temp_bpw = temp_bpw - BITS_PER_BYTE;
467 		}
468 	}
469 	cfg[iter - 1] |= PACKING_STOP_BIT;
470 	cfg0 = cfg[0] | (cfg[1] << PACKING_VECTOR_SHIFT);
471 	cfg1 = cfg[2] | (cfg[3] << PACKING_VECTOR_SHIFT);
472 
473 	if (tx_cfg) {
474 		writel_relaxed(cfg0, se->base + SE_GENI_TX_PACKING_CFG0);
475 		writel_relaxed(cfg1, se->base + SE_GENI_TX_PACKING_CFG1);
476 	}
477 	if (rx_cfg) {
478 		writel_relaxed(cfg0, se->base + SE_GENI_RX_PACKING_CFG0);
479 		writel_relaxed(cfg1, se->base + SE_GENI_RX_PACKING_CFG1);
480 	}
481 
482 	/*
483 	 * Number of protocol words in each FIFO entry
484 	 * 0 - 4x8, four words in each entry, max word size of 8 bits
485 	 * 1 - 2x16, two words in each entry, max word size of 16 bits
486 	 * 2 - 1x32, one word in each entry, max word size of 32 bits
487 	 * 3 - undefined
488 	 */
489 	if (pack_words || bpw == 32)
490 		writel_relaxed(bpw / 16, se->base + SE_GENI_BYTE_GRAN);
491 }
492 EXPORT_SYMBOL(geni_se_config_packing);
493 
494 static void geni_se_clks_off(struct geni_se *se)
495 {
496 	struct geni_wrapper *wrapper = se->wrapper;
497 
498 	clk_disable_unprepare(se->clk);
499 	clk_bulk_disable_unprepare(ARRAY_SIZE(wrapper->ahb_clks),
500 						wrapper->ahb_clks);
501 }
502 
503 /**
504  * geni_se_resources_off() - Turn off resources associated with the serial
505  *                           engine
506  * @se:	Pointer to the concerned serial engine.
507  *
508  * Return: 0 on success, standard Linux error codes on failure/error.
509  */
510 int geni_se_resources_off(struct geni_se *se)
511 {
512 	int ret;
513 
514 	if (has_acpi_companion(se->dev))
515 		return 0;
516 
517 	ret = pinctrl_pm_select_sleep_state(se->dev);
518 	if (ret)
519 		return ret;
520 
521 	geni_se_clks_off(se);
522 	return 0;
523 }
524 EXPORT_SYMBOL(geni_se_resources_off);
525 
526 static int geni_se_clks_on(struct geni_se *se)
527 {
528 	int ret;
529 	struct geni_wrapper *wrapper = se->wrapper;
530 
531 	ret = clk_bulk_prepare_enable(ARRAY_SIZE(wrapper->ahb_clks),
532 						wrapper->ahb_clks);
533 	if (ret)
534 		return ret;
535 
536 	ret = clk_prepare_enable(se->clk);
537 	if (ret)
538 		clk_bulk_disable_unprepare(ARRAY_SIZE(wrapper->ahb_clks),
539 							wrapper->ahb_clks);
540 	return ret;
541 }
542 
543 /**
544  * geni_se_resources_on() - Turn on resources associated with the serial
545  *                          engine
546  * @se:	Pointer to the concerned serial engine.
547  *
548  * Return: 0 on success, standard Linux error codes on failure/error.
549  */
550 int geni_se_resources_on(struct geni_se *se)
551 {
552 	int ret;
553 
554 	if (has_acpi_companion(se->dev))
555 		return 0;
556 
557 	ret = geni_se_clks_on(se);
558 	if (ret)
559 		return ret;
560 
561 	ret = pinctrl_pm_select_default_state(se->dev);
562 	if (ret)
563 		geni_se_clks_off(se);
564 
565 	return ret;
566 }
567 EXPORT_SYMBOL(geni_se_resources_on);
568 
569 /**
570  * geni_se_clk_tbl_get() - Get the clock table to program DFS
571  * @se:		Pointer to the concerned serial engine.
572  * @tbl:	Table in which the output is returned.
573  *
574  * This function is called by the protocol drivers to determine the different
575  * clock frequencies supported by serial engine core clock. The protocol
576  * drivers use the output to determine the clock frequency index to be
577  * programmed into DFS.
578  *
579  * Return: number of valid performance levels in the table on success,
580  *	   standard Linux error codes on failure.
581  */
582 int geni_se_clk_tbl_get(struct geni_se *se, unsigned long **tbl)
583 {
584 	long freq = 0;
585 	int i;
586 
587 	if (se->clk_perf_tbl) {
588 		*tbl = se->clk_perf_tbl;
589 		return se->num_clk_levels;
590 	}
591 
592 	se->clk_perf_tbl = devm_kcalloc(se->dev, MAX_CLK_PERF_LEVEL,
593 					sizeof(*se->clk_perf_tbl),
594 					GFP_KERNEL);
595 	if (!se->clk_perf_tbl)
596 		return -ENOMEM;
597 
598 	for (i = 0; i < MAX_CLK_PERF_LEVEL; i++) {
599 		freq = clk_round_rate(se->clk, freq + 1);
600 		if (freq <= 0 || freq == se->clk_perf_tbl[i - 1])
601 			break;
602 		se->clk_perf_tbl[i] = freq;
603 	}
604 	se->num_clk_levels = i;
605 	*tbl = se->clk_perf_tbl;
606 	return se->num_clk_levels;
607 }
608 EXPORT_SYMBOL(geni_se_clk_tbl_get);
609 
610 /**
611  * geni_se_clk_freq_match() - Get the matching or closest SE clock frequency
612  * @se:		Pointer to the concerned serial engine.
613  * @req_freq:	Requested clock frequency.
614  * @index:	Index of the resultant frequency in the table.
615  * @res_freq:	Resultant frequency of the source clock.
616  * @exact:	Flag to indicate exact multiple requirement of the requested
617  *		frequency.
618  *
619  * This function is called by the protocol drivers to determine the best match
620  * of the requested frequency as provided by the serial engine clock in order
621  * to meet the performance requirements.
622  *
623  * If we return success:
624  * - if @exact is true  then @res_freq / <an_integer> == @req_freq
625  * - if @exact is false then @res_freq / <an_integer> <= @req_freq
626  *
627  * Return: 0 on success, standard Linux error codes on failure.
628  */
629 int geni_se_clk_freq_match(struct geni_se *se, unsigned long req_freq,
630 			   unsigned int *index, unsigned long *res_freq,
631 			   bool exact)
632 {
633 	unsigned long *tbl;
634 	int num_clk_levels;
635 	int i;
636 	unsigned long best_delta;
637 	unsigned long new_delta;
638 	unsigned int divider;
639 
640 	num_clk_levels = geni_se_clk_tbl_get(se, &tbl);
641 	if (num_clk_levels < 0)
642 		return num_clk_levels;
643 
644 	if (num_clk_levels == 0)
645 		return -EINVAL;
646 
647 	best_delta = ULONG_MAX;
648 	for (i = 0; i < num_clk_levels; i++) {
649 		divider = DIV_ROUND_UP(tbl[i], req_freq);
650 		new_delta = req_freq - tbl[i] / divider;
651 		if (new_delta < best_delta) {
652 			/* We have a new best! */
653 			*index = i;
654 			*res_freq = tbl[i];
655 
656 			/* If the new best is exact then we're done */
657 			if (new_delta == 0)
658 				return 0;
659 
660 			/* Record how close we got */
661 			best_delta = new_delta;
662 		}
663 	}
664 
665 	if (exact)
666 		return -EINVAL;
667 
668 	return 0;
669 }
670 EXPORT_SYMBOL(geni_se_clk_freq_match);
671 
672 #define GENI_SE_DMA_DONE_EN BIT(0)
673 #define GENI_SE_DMA_EOT_EN BIT(1)
674 #define GENI_SE_DMA_AHB_ERR_EN BIT(2)
675 #define GENI_SE_DMA_EOT_BUF BIT(0)
676 /**
677  * geni_se_tx_dma_prep() - Prepare the serial engine for TX DMA transfer
678  * @se:			Pointer to the concerned serial engine.
679  * @buf:		Pointer to the TX buffer.
680  * @len:		Length of the TX buffer.
681  * @iova:		Pointer to store the mapped DMA address.
682  *
683  * This function is used to prepare the buffers for DMA TX.
684  *
685  * Return: 0 on success, standard Linux error codes on failure.
686  */
687 int geni_se_tx_dma_prep(struct geni_se *se, void *buf, size_t len,
688 			dma_addr_t *iova)
689 {
690 	struct geni_wrapper *wrapper = se->wrapper;
691 	u32 val;
692 
693 	if (!wrapper)
694 		return -EINVAL;
695 
696 	*iova = dma_map_single(wrapper->dev, buf, len, DMA_TO_DEVICE);
697 	if (dma_mapping_error(wrapper->dev, *iova))
698 		return -EIO;
699 
700 	val = GENI_SE_DMA_DONE_EN;
701 	val |= GENI_SE_DMA_EOT_EN;
702 	val |= GENI_SE_DMA_AHB_ERR_EN;
703 	writel_relaxed(val, se->base + SE_DMA_TX_IRQ_EN_SET);
704 	writel_relaxed(lower_32_bits(*iova), se->base + SE_DMA_TX_PTR_L);
705 	writel_relaxed(upper_32_bits(*iova), se->base + SE_DMA_TX_PTR_H);
706 	writel_relaxed(GENI_SE_DMA_EOT_BUF, se->base + SE_DMA_TX_ATTR);
707 	writel(len, se->base + SE_DMA_TX_LEN);
708 	return 0;
709 }
710 EXPORT_SYMBOL(geni_se_tx_dma_prep);
711 
712 /**
713  * geni_se_rx_dma_prep() - Prepare the serial engine for RX DMA transfer
714  * @se:			Pointer to the concerned serial engine.
715  * @buf:		Pointer to the RX buffer.
716  * @len:		Length of the RX buffer.
717  * @iova:		Pointer to store the mapped DMA address.
718  *
719  * This function is used to prepare the buffers for DMA RX.
720  *
721  * Return: 0 on success, standard Linux error codes on failure.
722  */
723 int geni_se_rx_dma_prep(struct geni_se *se, void *buf, size_t len,
724 			dma_addr_t *iova)
725 {
726 	struct geni_wrapper *wrapper = se->wrapper;
727 	u32 val;
728 
729 	if (!wrapper)
730 		return -EINVAL;
731 
732 	*iova = dma_map_single(wrapper->dev, buf, len, DMA_FROM_DEVICE);
733 	if (dma_mapping_error(wrapper->dev, *iova))
734 		return -EIO;
735 
736 	val = GENI_SE_DMA_DONE_EN;
737 	val |= GENI_SE_DMA_EOT_EN;
738 	val |= GENI_SE_DMA_AHB_ERR_EN;
739 	writel_relaxed(val, se->base + SE_DMA_RX_IRQ_EN_SET);
740 	writel_relaxed(lower_32_bits(*iova), se->base + SE_DMA_RX_PTR_L);
741 	writel_relaxed(upper_32_bits(*iova), se->base + SE_DMA_RX_PTR_H);
742 	/* RX does not have EOT buffer type bit. So just reset RX_ATTR */
743 	writel_relaxed(0, se->base + SE_DMA_RX_ATTR);
744 	writel(len, se->base + SE_DMA_RX_LEN);
745 	return 0;
746 }
747 EXPORT_SYMBOL(geni_se_rx_dma_prep);
748 
749 /**
750  * geni_se_tx_dma_unprep() - Unprepare the serial engine after TX DMA transfer
751  * @se:			Pointer to the concerned serial engine.
752  * @iova:		DMA address of the TX buffer.
753  * @len:		Length of the TX buffer.
754  *
755  * This function is used to unprepare the DMA buffers after DMA TX.
756  */
757 void geni_se_tx_dma_unprep(struct geni_se *se, dma_addr_t iova, size_t len)
758 {
759 	struct geni_wrapper *wrapper = se->wrapper;
760 
761 	if (!dma_mapping_error(wrapper->dev, iova))
762 		dma_unmap_single(wrapper->dev, iova, len, DMA_TO_DEVICE);
763 }
764 EXPORT_SYMBOL(geni_se_tx_dma_unprep);
765 
766 /**
767  * geni_se_rx_dma_unprep() - Unprepare the serial engine after RX DMA transfer
768  * @se:			Pointer to the concerned serial engine.
769  * @iova:		DMA address of the RX buffer.
770  * @len:		Length of the RX buffer.
771  *
772  * This function is used to unprepare the DMA buffers after DMA RX.
773  */
774 void geni_se_rx_dma_unprep(struct geni_se *se, dma_addr_t iova, size_t len)
775 {
776 	struct geni_wrapper *wrapper = se->wrapper;
777 
778 	if (!dma_mapping_error(wrapper->dev, iova))
779 		dma_unmap_single(wrapper->dev, iova, len, DMA_FROM_DEVICE);
780 }
781 EXPORT_SYMBOL(geni_se_rx_dma_unprep);
782 
783 int geni_icc_get(struct geni_se *se, const char *icc_ddr)
784 {
785 	int i, err;
786 	const char *icc_names[] = {"qup-core", "qup-config", icc_ddr};
787 
788 	if (has_acpi_companion(se->dev))
789 		return 0;
790 
791 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
792 		if (!icc_names[i])
793 			continue;
794 
795 		se->icc_paths[i].path = devm_of_icc_get(se->dev, icc_names[i]);
796 		if (IS_ERR(se->icc_paths[i].path))
797 			goto err;
798 	}
799 
800 	return 0;
801 
802 err:
803 	err = PTR_ERR(se->icc_paths[i].path);
804 	if (err != -EPROBE_DEFER)
805 		dev_err_ratelimited(se->dev, "Failed to get ICC path '%s': %d\n",
806 					icc_names[i], err);
807 	return err;
808 
809 }
810 EXPORT_SYMBOL(geni_icc_get);
811 
812 int geni_icc_set_bw(struct geni_se *se)
813 {
814 	int i, ret;
815 
816 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
817 		ret = icc_set_bw(se->icc_paths[i].path,
818 			se->icc_paths[i].avg_bw, se->icc_paths[i].avg_bw);
819 		if (ret) {
820 			dev_err_ratelimited(se->dev, "ICC BW voting failed on path '%s': %d\n",
821 					icc_path_names[i], ret);
822 			return ret;
823 		}
824 	}
825 
826 	return 0;
827 }
828 EXPORT_SYMBOL(geni_icc_set_bw);
829 
830 void geni_icc_set_tag(struct geni_se *se, u32 tag)
831 {
832 	int i;
833 
834 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++)
835 		icc_set_tag(se->icc_paths[i].path, tag);
836 }
837 EXPORT_SYMBOL(geni_icc_set_tag);
838 
839 /* To do: Replace this by icc_bulk_enable once it's implemented in ICC core */
840 int geni_icc_enable(struct geni_se *se)
841 {
842 	int i, ret;
843 
844 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
845 		ret = icc_enable(se->icc_paths[i].path);
846 		if (ret) {
847 			dev_err_ratelimited(se->dev, "ICC enable failed on path '%s': %d\n",
848 					icc_path_names[i], ret);
849 			return ret;
850 		}
851 	}
852 
853 	return 0;
854 }
855 EXPORT_SYMBOL(geni_icc_enable);
856 
857 int geni_icc_disable(struct geni_se *se)
858 {
859 	int i, ret;
860 
861 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
862 		ret = icc_disable(se->icc_paths[i].path);
863 		if (ret) {
864 			dev_err_ratelimited(se->dev, "ICC disable failed on path '%s': %d\n",
865 					icc_path_names[i], ret);
866 			return ret;
867 		}
868 	}
869 
870 	return 0;
871 }
872 EXPORT_SYMBOL(geni_icc_disable);
873 
874 static int geni_se_probe(struct platform_device *pdev)
875 {
876 	struct device *dev = &pdev->dev;
877 	struct geni_wrapper *wrapper;
878 	int ret;
879 
880 	wrapper = devm_kzalloc(dev, sizeof(*wrapper), GFP_KERNEL);
881 	if (!wrapper)
882 		return -ENOMEM;
883 
884 	wrapper->dev = dev;
885 	wrapper->base = devm_platform_ioremap_resource(pdev, 0);
886 	if (IS_ERR(wrapper->base))
887 		return PTR_ERR(wrapper->base);
888 
889 	if (!has_acpi_companion(&pdev->dev)) {
890 		wrapper->ahb_clks[0].id = "m-ahb";
891 		wrapper->ahb_clks[1].id = "s-ahb";
892 		ret = devm_clk_bulk_get(dev, NUM_AHB_CLKS, wrapper->ahb_clks);
893 		if (ret) {
894 			dev_err(dev, "Err getting AHB clks %d\n", ret);
895 			return ret;
896 		}
897 	}
898 
899 	dev_set_drvdata(dev, wrapper);
900 	dev_dbg(dev, "GENI SE Driver probed\n");
901 	return devm_of_platform_populate(dev);
902 }
903 
904 static const struct of_device_id geni_se_dt_match[] = {
905 	{ .compatible = "qcom,geni-se-qup", },
906 	{}
907 };
908 MODULE_DEVICE_TABLE(of, geni_se_dt_match);
909 
910 static struct platform_driver geni_se_driver = {
911 	.driver = {
912 		.name = "geni_se_qup",
913 		.of_match_table = geni_se_dt_match,
914 	},
915 	.probe = geni_se_probe,
916 };
917 module_platform_driver(geni_se_driver);
918 
919 MODULE_DESCRIPTION("GENI Serial Engine Driver");
920 MODULE_LICENSE("GPL v2");
921