xref: /openbmc/linux/drivers/soc/qcom/qcom-geni-se.c (revision fe7498ef)
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/slab.h>
7 #include <linux/dma-mapping.h>
8 #include <linux/io.h>
9 #include <linux/module.h>
10 #include <linux/of.h>
11 #include <linux/of_platform.h>
12 #include <linux/pinctrl/consumer.h>
13 #include <linux/platform_device.h>
14 #include <linux/qcom-geni-se.h>
15 
16 /**
17  * DOC: Overview
18  *
19  * Generic Interface (GENI) Serial Engine (SE) Wrapper driver is introduced
20  * to manage GENI firmware based Qualcomm Universal Peripheral (QUP) Wrapper
21  * controller. QUP Wrapper is designed to support various serial bus protocols
22  * like UART, SPI, I2C, I3C, etc.
23  */
24 
25 /**
26  * DOC: Hardware description
27  *
28  * GENI based QUP is a highly-flexible and programmable module for supporting
29  * a wide range of serial interfaces like UART, SPI, I2C, I3C, etc. A single
30  * QUP module can provide upto 8 serial interfaces, using its internal
31  * serial engines. The actual configuration is determined by the target
32  * platform configuration. The protocol supported by each interface is
33  * determined by the firmware loaded to the serial engine. Each SE consists
34  * of a DMA Engine and GENI sub modules which enable serial engines to
35  * support FIFO and DMA modes of operation.
36  *
37  *
38  *                      +-----------------------------------------+
39  *                      |QUP Wrapper                              |
40  *                      |         +----------------------------+  |
41  *   --QUP & SE Clocks-->         | Serial Engine N            |  +-IO------>
42  *                      |         | ...                        |  | Interface
43  *   <---Clock Perf.----+    +----+-----------------------+    |  |
44  *     State Interface  |    | Serial Engine 1            |    |  |
45  *                      |    |                            |    |  |
46  *                      |    |                            |    |  |
47  *   <--------AHB------->    |                            |    |  |
48  *                      |    |                            +----+  |
49  *                      |    |                            |       |
50  *                      |    |                            |       |
51  *   <------SE IRQ------+    +----------------------------+       |
52  *                      |                                         |
53  *                      +-----------------------------------------+
54  *
55  *                         Figure 1: GENI based QUP Wrapper
56  *
57  * The GENI submodules include primary and secondary sequencers which are
58  * used to drive TX & RX operations. On serial interfaces that operate using
59  * master-slave model, primary sequencer drives both TX & RX operations. On
60  * serial interfaces that operate using peer-to-peer model, primary sequencer
61  * drives TX operation and secondary sequencer drives RX operation.
62  */
63 
64 /**
65  * DOC: Software description
66  *
67  * GENI SE Wrapper driver is structured into 2 parts:
68  *
69  * geni_wrapper represents QUP Wrapper controller. This part of the driver
70  * manages QUP Wrapper information such as hardware version, clock
71  * performance table that is common to all the internal serial engines.
72  *
73  * geni_se represents serial engine. This part of the driver manages serial
74  * engine information such as clocks, containing QUP Wrapper, etc. This part
75  * of driver also supports operations (eg. initialize the concerned serial
76  * engine, select between FIFO and DMA mode of operation etc.) that are
77  * common to all the serial engines and are independent of serial interfaces.
78  */
79 
80 #define MAX_CLK_PERF_LEVEL 32
81 #define NUM_AHB_CLKS 2
82 
83 /**
84  * struct geni_wrapper - Data structure to represent the QUP Wrapper Core
85  * @dev:		Device pointer of the QUP wrapper core
86  * @base:		Base address of this instance of QUP wrapper core
87  * @ahb_clks:		Handle to the primary & secondary AHB clocks
88  * @to_core:		Core ICC path
89  */
90 struct geni_wrapper {
91 	struct device *dev;
92 	void __iomem *base;
93 	struct clk_bulk_data ahb_clks[NUM_AHB_CLKS];
94 };
95 
96 static const char * const icc_path_names[] = {"qup-core", "qup-config",
97 						"qup-memory"};
98 
99 #define QUP_HW_VER_REG			0x4
100 
101 /* Common SE registers */
102 #define GENI_INIT_CFG_REVISION		0x0
103 #define GENI_S_INIT_CFG_REVISION	0x4
104 #define GENI_OUTPUT_CTRL		0x24
105 #define GENI_CGC_CTRL			0x28
106 #define GENI_CLK_CTRL_RO		0x60
107 #define GENI_FW_S_REVISION_RO		0x6c
108 #define SE_GENI_BYTE_GRAN		0x254
109 #define SE_GENI_TX_PACKING_CFG0		0x260
110 #define SE_GENI_TX_PACKING_CFG1		0x264
111 #define SE_GENI_RX_PACKING_CFG0		0x284
112 #define SE_GENI_RX_PACKING_CFG1		0x288
113 #define SE_GENI_M_GP_LENGTH		0x910
114 #define SE_GENI_S_GP_LENGTH		0x914
115 #define SE_DMA_TX_PTR_L			0xc30
116 #define SE_DMA_TX_PTR_H			0xc34
117 #define SE_DMA_TX_ATTR			0xc38
118 #define SE_DMA_TX_LEN			0xc3c
119 #define SE_DMA_TX_IRQ_EN		0xc48
120 #define SE_DMA_TX_IRQ_EN_SET		0xc4c
121 #define SE_DMA_TX_IRQ_EN_CLR		0xc50
122 #define SE_DMA_TX_LEN_IN		0xc54
123 #define SE_DMA_TX_MAX_BURST		0xc5c
124 #define SE_DMA_RX_PTR_L			0xd30
125 #define SE_DMA_RX_PTR_H			0xd34
126 #define SE_DMA_RX_ATTR			0xd38
127 #define SE_DMA_RX_LEN			0xd3c
128 #define SE_DMA_RX_IRQ_EN		0xd48
129 #define SE_DMA_RX_IRQ_EN_SET		0xd4c
130 #define SE_DMA_RX_IRQ_EN_CLR		0xd50
131 #define SE_DMA_RX_LEN_IN		0xd54
132 #define SE_DMA_RX_MAX_BURST		0xd5c
133 #define SE_DMA_RX_FLUSH			0xd60
134 #define SE_GSI_EVENT_EN			0xe18
135 #define SE_IRQ_EN			0xe1c
136 #define SE_DMA_GENERAL_CFG		0xe30
137 
138 /* GENI_OUTPUT_CTRL fields */
139 #define DEFAULT_IO_OUTPUT_CTRL_MSK	GENMASK(6, 0)
140 
141 /* GENI_CGC_CTRL fields */
142 #define CFG_AHB_CLK_CGC_ON		BIT(0)
143 #define CFG_AHB_WR_ACLK_CGC_ON		BIT(1)
144 #define DATA_AHB_CLK_CGC_ON		BIT(2)
145 #define SCLK_CGC_ON			BIT(3)
146 #define TX_CLK_CGC_ON			BIT(4)
147 #define RX_CLK_CGC_ON			BIT(5)
148 #define EXT_CLK_CGC_ON			BIT(6)
149 #define PROG_RAM_HCLK_OFF		BIT(8)
150 #define PROG_RAM_SCLK_OFF		BIT(9)
151 #define DEFAULT_CGC_EN			GENMASK(6, 0)
152 
153 /* SE_GSI_EVENT_EN fields */
154 #define DMA_RX_EVENT_EN			BIT(0)
155 #define DMA_TX_EVENT_EN			BIT(1)
156 #define GENI_M_EVENT_EN			BIT(2)
157 #define GENI_S_EVENT_EN			BIT(3)
158 
159 /* SE_IRQ_EN fields */
160 #define DMA_RX_IRQ_EN			BIT(0)
161 #define DMA_TX_IRQ_EN			BIT(1)
162 #define GENI_M_IRQ_EN			BIT(2)
163 #define GENI_S_IRQ_EN			BIT(3)
164 
165 /* SE_DMA_GENERAL_CFG */
166 #define DMA_RX_CLK_CGC_ON		BIT(0)
167 #define DMA_TX_CLK_CGC_ON		BIT(1)
168 #define DMA_AHB_SLV_CFG_ON		BIT(2)
169 #define AHB_SEC_SLV_CLK_CGC_ON		BIT(3)
170 #define DUMMY_RX_NON_BUFFERABLE		BIT(4)
171 #define RX_DMA_ZERO_PADDING_EN		BIT(5)
172 #define RX_DMA_IRQ_DELAY_MSK		GENMASK(8, 6)
173 #define RX_DMA_IRQ_DELAY_SHFT		6
174 
175 /**
176  * geni_se_get_qup_hw_version() - Read the QUP wrapper Hardware version
177  * @se:	Pointer to the corresponding serial engine.
178  *
179  * Return: Hardware Version of the wrapper.
180  */
181 u32 geni_se_get_qup_hw_version(struct geni_se *se)
182 {
183 	struct geni_wrapper *wrapper = se->wrapper;
184 
185 	return readl_relaxed(wrapper->base + QUP_HW_VER_REG);
186 }
187 EXPORT_SYMBOL(geni_se_get_qup_hw_version);
188 
189 static void geni_se_io_set_mode(void __iomem *base)
190 {
191 	u32 val;
192 
193 	val = readl_relaxed(base + SE_IRQ_EN);
194 	val |= GENI_M_IRQ_EN | GENI_S_IRQ_EN;
195 	val |= DMA_TX_IRQ_EN | DMA_RX_IRQ_EN;
196 	writel_relaxed(val, base + SE_IRQ_EN);
197 
198 	val = readl_relaxed(base + SE_GENI_DMA_MODE_EN);
199 	val &= ~GENI_DMA_MODE_EN;
200 	writel_relaxed(val, base + SE_GENI_DMA_MODE_EN);
201 
202 	writel_relaxed(0, base + SE_GSI_EVENT_EN);
203 }
204 
205 static void geni_se_io_init(void __iomem *base)
206 {
207 	u32 val;
208 
209 	val = readl_relaxed(base + GENI_CGC_CTRL);
210 	val |= DEFAULT_CGC_EN;
211 	writel_relaxed(val, base + GENI_CGC_CTRL);
212 
213 	val = readl_relaxed(base + SE_DMA_GENERAL_CFG);
214 	val |= AHB_SEC_SLV_CLK_CGC_ON | DMA_AHB_SLV_CFG_ON;
215 	val |= DMA_TX_CLK_CGC_ON | DMA_RX_CLK_CGC_ON;
216 	writel_relaxed(val, base + SE_DMA_GENERAL_CFG);
217 
218 	writel_relaxed(DEFAULT_IO_OUTPUT_CTRL_MSK, base + GENI_OUTPUT_CTRL);
219 	writel_relaxed(FORCE_DEFAULT, base + GENI_FORCE_DEFAULT_REG);
220 }
221 
222 static void geni_se_irq_clear(struct geni_se *se)
223 {
224 	writel_relaxed(0, se->base + SE_GSI_EVENT_EN);
225 	writel_relaxed(0xffffffff, se->base + SE_GENI_M_IRQ_CLEAR);
226 	writel_relaxed(0xffffffff, se->base + SE_GENI_S_IRQ_CLEAR);
227 	writel_relaxed(0xffffffff, se->base + SE_DMA_TX_IRQ_CLR);
228 	writel_relaxed(0xffffffff, se->base + SE_DMA_RX_IRQ_CLR);
229 	writel_relaxed(0xffffffff, se->base + SE_IRQ_EN);
230 }
231 
232 /**
233  * geni_se_init() - Initialize the GENI serial engine
234  * @se:		Pointer to the concerned serial engine.
235  * @rx_wm:	Receive watermark, in units of FIFO words.
236  * @rx_rfr:	Ready-for-receive watermark, in units of FIFO words.
237  *
238  * This function is used to initialize the GENI serial engine, configure
239  * receive watermark and ready-for-receive watermarks.
240  */
241 void geni_se_init(struct geni_se *se, u32 rx_wm, u32 rx_rfr)
242 {
243 	u32 val;
244 
245 	geni_se_irq_clear(se);
246 	geni_se_io_init(se->base);
247 	geni_se_io_set_mode(se->base);
248 
249 	writel_relaxed(rx_wm, se->base + SE_GENI_RX_WATERMARK_REG);
250 	writel_relaxed(rx_rfr, se->base + SE_GENI_RX_RFR_WATERMARK_REG);
251 
252 	val = readl_relaxed(se->base + SE_GENI_M_IRQ_EN);
253 	val |= M_COMMON_GENI_M_IRQ_EN;
254 	writel_relaxed(val, se->base + SE_GENI_M_IRQ_EN);
255 
256 	val = readl_relaxed(se->base + SE_GENI_S_IRQ_EN);
257 	val |= S_COMMON_GENI_S_IRQ_EN;
258 	writel_relaxed(val, se->base + SE_GENI_S_IRQ_EN);
259 }
260 EXPORT_SYMBOL(geni_se_init);
261 
262 static void geni_se_select_fifo_mode(struct geni_se *se)
263 {
264 	u32 proto = geni_se_read_proto(se);
265 	u32 val, val_old;
266 
267 	geni_se_irq_clear(se);
268 
269 	/*
270 	 * The RX path for the UART is asynchronous and so needs more
271 	 * complex logic for enabling / disabling its interrupts.
272 	 *
273 	 * Specific notes:
274 	 * - The done and TX-related interrupts are managed manually.
275 	 * - We don't RX from the main sequencer (we use the secondary) so
276 	 *   we don't need the RX-related interrupts enabled in the main
277 	 *   sequencer for UART.
278 	 */
279 	if (proto != GENI_SE_UART) {
280 		val_old = val = readl_relaxed(se->base + SE_GENI_M_IRQ_EN);
281 		val |= M_CMD_DONE_EN | M_TX_FIFO_WATERMARK_EN;
282 		val |= M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN;
283 		if (val != val_old)
284 			writel_relaxed(val, se->base + SE_GENI_M_IRQ_EN);
285 
286 		val_old = val = readl_relaxed(se->base + SE_GENI_S_IRQ_EN);
287 		val |= S_CMD_DONE_EN;
288 		if (val != val_old)
289 			writel_relaxed(val, se->base + SE_GENI_S_IRQ_EN);
290 	}
291 
292 	val_old = val = readl_relaxed(se->base + SE_GENI_DMA_MODE_EN);
293 	val &= ~GENI_DMA_MODE_EN;
294 	if (val != val_old)
295 		writel_relaxed(val, se->base + SE_GENI_DMA_MODE_EN);
296 }
297 
298 static void geni_se_select_dma_mode(struct geni_se *se)
299 {
300 	u32 proto = geni_se_read_proto(se);
301 	u32 val, val_old;
302 
303 	geni_se_irq_clear(se);
304 
305 	if (proto != GENI_SE_UART) {
306 		val_old = val = readl_relaxed(se->base + SE_GENI_M_IRQ_EN);
307 		val &= ~(M_CMD_DONE_EN | M_TX_FIFO_WATERMARK_EN);
308 		val &= ~(M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN);
309 		if (val != val_old)
310 			writel_relaxed(val, se->base + SE_GENI_M_IRQ_EN);
311 
312 		val_old = val = readl_relaxed(se->base + SE_GENI_S_IRQ_EN);
313 		val &= ~S_CMD_DONE_EN;
314 		if (val != val_old)
315 			writel_relaxed(val, se->base + SE_GENI_S_IRQ_EN);
316 	}
317 
318 	val_old = val = readl_relaxed(se->base + SE_GENI_DMA_MODE_EN);
319 	val |= GENI_DMA_MODE_EN;
320 	if (val != val_old)
321 		writel_relaxed(val, se->base + SE_GENI_DMA_MODE_EN);
322 }
323 
324 static void geni_se_select_gpi_mode(struct geni_se *se)
325 {
326 	u32 val;
327 
328 	geni_se_irq_clear(se);
329 
330 	writel(0, se->base + SE_IRQ_EN);
331 
332 	val = readl(se->base + SE_GENI_S_IRQ_EN);
333 	val &= ~S_CMD_DONE_EN;
334 	writel(val, se->base + SE_GENI_S_IRQ_EN);
335 
336 	val = readl(se->base + SE_GENI_M_IRQ_EN);
337 	val &= ~(M_CMD_DONE_EN | M_TX_FIFO_WATERMARK_EN |
338 		 M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN);
339 	writel(val, se->base + SE_GENI_M_IRQ_EN);
340 
341 	writel(GENI_DMA_MODE_EN, se->base + SE_GENI_DMA_MODE_EN);
342 
343 	val = readl(se->base + SE_GSI_EVENT_EN);
344 	val |= (DMA_RX_EVENT_EN | DMA_TX_EVENT_EN | GENI_M_EVENT_EN | GENI_S_EVENT_EN);
345 	writel(val, se->base + SE_GSI_EVENT_EN);
346 }
347 
348 /**
349  * geni_se_select_mode() - Select the serial engine transfer mode
350  * @se:		Pointer to the concerned serial engine.
351  * @mode:	Transfer mode to be selected.
352  */
353 void geni_se_select_mode(struct geni_se *se, enum geni_se_xfer_mode mode)
354 {
355 	WARN_ON(mode != GENI_SE_FIFO && mode != GENI_SE_DMA && mode != GENI_GPI_DMA);
356 
357 	switch (mode) {
358 	case GENI_SE_FIFO:
359 		geni_se_select_fifo_mode(se);
360 		break;
361 	case GENI_SE_DMA:
362 		geni_se_select_dma_mode(se);
363 		break;
364 	case GENI_GPI_DMA:
365 		geni_se_select_gpi_mode(se);
366 		break;
367 	case GENI_SE_INVALID:
368 	default:
369 		break;
370 	}
371 }
372 EXPORT_SYMBOL(geni_se_select_mode);
373 
374 /**
375  * DOC: Overview
376  *
377  * GENI FIFO packing is highly configurable. TX/RX packing/unpacking consist
378  * of up to 4 operations, each operation represented by 4 configuration vectors
379  * of 10 bits programmed in GENI_TX_PACKING_CFG0 and GENI_TX_PACKING_CFG1 for
380  * TX FIFO and in GENI_RX_PACKING_CFG0 and GENI_RX_PACKING_CFG1 for RX FIFO.
381  * Refer to below examples for detailed bit-field description.
382  *
383  * Example 1: word_size = 7, packing_mode = 4 x 8, msb_to_lsb = 1
384  *
385  *        +-----------+-------+-------+-------+-------+
386  *        |           | vec_0 | vec_1 | vec_2 | vec_3 |
387  *        +-----------+-------+-------+-------+-------+
388  *        | start     | 0x6   | 0xe   | 0x16  | 0x1e  |
389  *        | direction | 1     | 1     | 1     | 1     |
390  *        | length    | 6     | 6     | 6     | 6     |
391  *        | stop      | 0     | 0     | 0     | 1     |
392  *        +-----------+-------+-------+-------+-------+
393  *
394  * Example 2: word_size = 15, packing_mode = 2 x 16, msb_to_lsb = 0
395  *
396  *        +-----------+-------+-------+-------+-------+
397  *        |           | vec_0 | vec_1 | vec_2 | vec_3 |
398  *        +-----------+-------+-------+-------+-------+
399  *        | start     | 0x0   | 0x8   | 0x10  | 0x18  |
400  *        | direction | 0     | 0     | 0     | 0     |
401  *        | length    | 7     | 6     | 7     | 6     |
402  *        | stop      | 0     | 0     | 0     | 1     |
403  *        +-----------+-------+-------+-------+-------+
404  *
405  * Example 3: word_size = 23, packing_mode = 1 x 32, msb_to_lsb = 1
406  *
407  *        +-----------+-------+-------+-------+-------+
408  *        |           | vec_0 | vec_1 | vec_2 | vec_3 |
409  *        +-----------+-------+-------+-------+-------+
410  *        | start     | 0x16  | 0xe   | 0x6   | 0x0   |
411  *        | direction | 1     | 1     | 1     | 1     |
412  *        | length    | 7     | 7     | 6     | 0     |
413  *        | stop      | 0     | 0     | 1     | 0     |
414  *        +-----------+-------+-------+-------+-------+
415  *
416  */
417 
418 #define NUM_PACKING_VECTORS 4
419 #define PACKING_START_SHIFT 5
420 #define PACKING_DIR_SHIFT 4
421 #define PACKING_LEN_SHIFT 1
422 #define PACKING_STOP_BIT BIT(0)
423 #define PACKING_VECTOR_SHIFT 10
424 /**
425  * geni_se_config_packing() - Packing configuration of the serial engine
426  * @se:		Pointer to the concerned serial engine
427  * @bpw:	Bits of data per transfer word.
428  * @pack_words:	Number of words per fifo element.
429  * @msb_to_lsb:	Transfer from MSB to LSB or vice-versa.
430  * @tx_cfg:	Flag to configure the TX Packing.
431  * @rx_cfg:	Flag to configure the RX Packing.
432  *
433  * This function is used to configure the packing rules for the current
434  * transfer.
435  */
436 void geni_se_config_packing(struct geni_se *se, int bpw, int pack_words,
437 			    bool msb_to_lsb, bool tx_cfg, bool rx_cfg)
438 {
439 	u32 cfg0, cfg1, cfg[NUM_PACKING_VECTORS] = {0};
440 	int len;
441 	int temp_bpw = bpw;
442 	int idx_start = msb_to_lsb ? bpw - 1 : 0;
443 	int idx = idx_start;
444 	int idx_delta = msb_to_lsb ? -BITS_PER_BYTE : BITS_PER_BYTE;
445 	int ceil_bpw = ALIGN(bpw, BITS_PER_BYTE);
446 	int iter = (ceil_bpw * pack_words) / BITS_PER_BYTE;
447 	int i;
448 
449 	if (iter <= 0 || iter > NUM_PACKING_VECTORS)
450 		return;
451 
452 	for (i = 0; i < iter; i++) {
453 		len = min_t(int, temp_bpw, BITS_PER_BYTE) - 1;
454 		cfg[i] = idx << PACKING_START_SHIFT;
455 		cfg[i] |= msb_to_lsb << PACKING_DIR_SHIFT;
456 		cfg[i] |= len << PACKING_LEN_SHIFT;
457 
458 		if (temp_bpw <= BITS_PER_BYTE) {
459 			idx = ((i + 1) * BITS_PER_BYTE) + idx_start;
460 			temp_bpw = bpw;
461 		} else {
462 			idx = idx + idx_delta;
463 			temp_bpw = temp_bpw - BITS_PER_BYTE;
464 		}
465 	}
466 	cfg[iter - 1] |= PACKING_STOP_BIT;
467 	cfg0 = cfg[0] | (cfg[1] << PACKING_VECTOR_SHIFT);
468 	cfg1 = cfg[2] | (cfg[3] << PACKING_VECTOR_SHIFT);
469 
470 	if (tx_cfg) {
471 		writel_relaxed(cfg0, se->base + SE_GENI_TX_PACKING_CFG0);
472 		writel_relaxed(cfg1, se->base + SE_GENI_TX_PACKING_CFG1);
473 	}
474 	if (rx_cfg) {
475 		writel_relaxed(cfg0, se->base + SE_GENI_RX_PACKING_CFG0);
476 		writel_relaxed(cfg1, se->base + SE_GENI_RX_PACKING_CFG1);
477 	}
478 
479 	/*
480 	 * Number of protocol words in each FIFO entry
481 	 * 0 - 4x8, four words in each entry, max word size of 8 bits
482 	 * 1 - 2x16, two words in each entry, max word size of 16 bits
483 	 * 2 - 1x32, one word in each entry, max word size of 32 bits
484 	 * 3 - undefined
485 	 */
486 	if (pack_words || bpw == 32)
487 		writel_relaxed(bpw / 16, se->base + SE_GENI_BYTE_GRAN);
488 }
489 EXPORT_SYMBOL(geni_se_config_packing);
490 
491 static void geni_se_clks_off(struct geni_se *se)
492 {
493 	struct geni_wrapper *wrapper = se->wrapper;
494 
495 	clk_disable_unprepare(se->clk);
496 	clk_bulk_disable_unprepare(ARRAY_SIZE(wrapper->ahb_clks),
497 						wrapper->ahb_clks);
498 }
499 
500 /**
501  * geni_se_resources_off() - Turn off resources associated with the serial
502  *                           engine
503  * @se:	Pointer to the concerned serial engine.
504  *
505  * Return: 0 on success, standard Linux error codes on failure/error.
506  */
507 int geni_se_resources_off(struct geni_se *se)
508 {
509 	int ret;
510 
511 	if (has_acpi_companion(se->dev))
512 		return 0;
513 
514 	ret = pinctrl_pm_select_sleep_state(se->dev);
515 	if (ret)
516 		return ret;
517 
518 	geni_se_clks_off(se);
519 	return 0;
520 }
521 EXPORT_SYMBOL(geni_se_resources_off);
522 
523 static int geni_se_clks_on(struct geni_se *se)
524 {
525 	int ret;
526 	struct geni_wrapper *wrapper = se->wrapper;
527 
528 	ret = clk_bulk_prepare_enable(ARRAY_SIZE(wrapper->ahb_clks),
529 						wrapper->ahb_clks);
530 	if (ret)
531 		return ret;
532 
533 	ret = clk_prepare_enable(se->clk);
534 	if (ret)
535 		clk_bulk_disable_unprepare(ARRAY_SIZE(wrapper->ahb_clks),
536 							wrapper->ahb_clks);
537 	return ret;
538 }
539 
540 /**
541  * geni_se_resources_on() - Turn on resources associated with the serial
542  *                          engine
543  * @se:	Pointer to the concerned serial engine.
544  *
545  * Return: 0 on success, standard Linux error codes on failure/error.
546  */
547 int geni_se_resources_on(struct geni_se *se)
548 {
549 	int ret;
550 
551 	if (has_acpi_companion(se->dev))
552 		return 0;
553 
554 	ret = geni_se_clks_on(se);
555 	if (ret)
556 		return ret;
557 
558 	ret = pinctrl_pm_select_default_state(se->dev);
559 	if (ret)
560 		geni_se_clks_off(se);
561 
562 	return ret;
563 }
564 EXPORT_SYMBOL(geni_se_resources_on);
565 
566 /**
567  * geni_se_clk_tbl_get() - Get the clock table to program DFS
568  * @se:		Pointer to the concerned serial engine.
569  * @tbl:	Table in which the output is returned.
570  *
571  * This function is called by the protocol drivers to determine the different
572  * clock frequencies supported by serial engine core clock. The protocol
573  * drivers use the output to determine the clock frequency index to be
574  * programmed into DFS.
575  *
576  * Return: number of valid performance levels in the table on success,
577  *	   standard Linux error codes on failure.
578  */
579 int geni_se_clk_tbl_get(struct geni_se *se, unsigned long **tbl)
580 {
581 	long freq = 0;
582 	int i;
583 
584 	if (se->clk_perf_tbl) {
585 		*tbl = se->clk_perf_tbl;
586 		return se->num_clk_levels;
587 	}
588 
589 	se->clk_perf_tbl = devm_kcalloc(se->dev, MAX_CLK_PERF_LEVEL,
590 					sizeof(*se->clk_perf_tbl),
591 					GFP_KERNEL);
592 	if (!se->clk_perf_tbl)
593 		return -ENOMEM;
594 
595 	for (i = 0; i < MAX_CLK_PERF_LEVEL; i++) {
596 		freq = clk_round_rate(se->clk, freq + 1);
597 		if (freq <= 0 || freq == se->clk_perf_tbl[i - 1])
598 			break;
599 		se->clk_perf_tbl[i] = freq;
600 	}
601 	se->num_clk_levels = i;
602 	*tbl = se->clk_perf_tbl;
603 	return se->num_clk_levels;
604 }
605 EXPORT_SYMBOL(geni_se_clk_tbl_get);
606 
607 /**
608  * geni_se_clk_freq_match() - Get the matching or closest SE clock frequency
609  * @se:		Pointer to the concerned serial engine.
610  * @req_freq:	Requested clock frequency.
611  * @index:	Index of the resultant frequency in the table.
612  * @res_freq:	Resultant frequency of the source clock.
613  * @exact:	Flag to indicate exact multiple requirement of the requested
614  *		frequency.
615  *
616  * This function is called by the protocol drivers to determine the best match
617  * of the requested frequency as provided by the serial engine clock in order
618  * to meet the performance requirements.
619  *
620  * If we return success:
621  * - if @exact is true  then @res_freq / <an_integer> == @req_freq
622  * - if @exact is false then @res_freq / <an_integer> <= @req_freq
623  *
624  * Return: 0 on success, standard Linux error codes on failure.
625  */
626 int geni_se_clk_freq_match(struct geni_se *se, unsigned long req_freq,
627 			   unsigned int *index, unsigned long *res_freq,
628 			   bool exact)
629 {
630 	unsigned long *tbl;
631 	int num_clk_levels;
632 	int i;
633 	unsigned long best_delta;
634 	unsigned long new_delta;
635 	unsigned int divider;
636 
637 	num_clk_levels = geni_se_clk_tbl_get(se, &tbl);
638 	if (num_clk_levels < 0)
639 		return num_clk_levels;
640 
641 	if (num_clk_levels == 0)
642 		return -EINVAL;
643 
644 	best_delta = ULONG_MAX;
645 	for (i = 0; i < num_clk_levels; i++) {
646 		divider = DIV_ROUND_UP(tbl[i], req_freq);
647 		new_delta = req_freq - tbl[i] / divider;
648 		if (new_delta < best_delta) {
649 			/* We have a new best! */
650 			*index = i;
651 			*res_freq = tbl[i];
652 
653 			/* If the new best is exact then we're done */
654 			if (new_delta == 0)
655 				return 0;
656 
657 			/* Record how close we got */
658 			best_delta = new_delta;
659 		}
660 	}
661 
662 	if (exact)
663 		return -EINVAL;
664 
665 	return 0;
666 }
667 EXPORT_SYMBOL(geni_se_clk_freq_match);
668 
669 #define GENI_SE_DMA_DONE_EN BIT(0)
670 #define GENI_SE_DMA_EOT_EN BIT(1)
671 #define GENI_SE_DMA_AHB_ERR_EN BIT(2)
672 #define GENI_SE_DMA_EOT_BUF BIT(0)
673 /**
674  * geni_se_tx_dma_prep() - Prepare the serial engine for TX DMA transfer
675  * @se:			Pointer to the concerned serial engine.
676  * @buf:		Pointer to the TX buffer.
677  * @len:		Length of the TX buffer.
678  * @iova:		Pointer to store the mapped DMA address.
679  *
680  * This function is used to prepare the buffers for DMA TX.
681  *
682  * Return: 0 on success, standard Linux error codes on failure.
683  */
684 int geni_se_tx_dma_prep(struct geni_se *se, void *buf, size_t len,
685 			dma_addr_t *iova)
686 {
687 	struct geni_wrapper *wrapper = se->wrapper;
688 	u32 val;
689 
690 	if (!wrapper)
691 		return -EINVAL;
692 
693 	*iova = dma_map_single(wrapper->dev, buf, len, DMA_TO_DEVICE);
694 	if (dma_mapping_error(wrapper->dev, *iova))
695 		return -EIO;
696 
697 	val = GENI_SE_DMA_DONE_EN;
698 	val |= GENI_SE_DMA_EOT_EN;
699 	val |= GENI_SE_DMA_AHB_ERR_EN;
700 	writel_relaxed(val, se->base + SE_DMA_TX_IRQ_EN_SET);
701 	writel_relaxed(lower_32_bits(*iova), se->base + SE_DMA_TX_PTR_L);
702 	writel_relaxed(upper_32_bits(*iova), se->base + SE_DMA_TX_PTR_H);
703 	writel_relaxed(GENI_SE_DMA_EOT_BUF, se->base + SE_DMA_TX_ATTR);
704 	writel(len, se->base + SE_DMA_TX_LEN);
705 	return 0;
706 }
707 EXPORT_SYMBOL(geni_se_tx_dma_prep);
708 
709 /**
710  * geni_se_rx_dma_prep() - Prepare the serial engine for RX DMA transfer
711  * @se:			Pointer to the concerned serial engine.
712  * @buf:		Pointer to the RX buffer.
713  * @len:		Length of the RX buffer.
714  * @iova:		Pointer to store the mapped DMA address.
715  *
716  * This function is used to prepare the buffers for DMA RX.
717  *
718  * Return: 0 on success, standard Linux error codes on failure.
719  */
720 int geni_se_rx_dma_prep(struct geni_se *se, void *buf, size_t len,
721 			dma_addr_t *iova)
722 {
723 	struct geni_wrapper *wrapper = se->wrapper;
724 	u32 val;
725 
726 	if (!wrapper)
727 		return -EINVAL;
728 
729 	*iova = dma_map_single(wrapper->dev, buf, len, DMA_FROM_DEVICE);
730 	if (dma_mapping_error(wrapper->dev, *iova))
731 		return -EIO;
732 
733 	val = GENI_SE_DMA_DONE_EN;
734 	val |= GENI_SE_DMA_EOT_EN;
735 	val |= GENI_SE_DMA_AHB_ERR_EN;
736 	writel_relaxed(val, se->base + SE_DMA_RX_IRQ_EN_SET);
737 	writel_relaxed(lower_32_bits(*iova), se->base + SE_DMA_RX_PTR_L);
738 	writel_relaxed(upper_32_bits(*iova), se->base + SE_DMA_RX_PTR_H);
739 	/* RX does not have EOT buffer type bit. So just reset RX_ATTR */
740 	writel_relaxed(0, se->base + SE_DMA_RX_ATTR);
741 	writel(len, se->base + SE_DMA_RX_LEN);
742 	return 0;
743 }
744 EXPORT_SYMBOL(geni_se_rx_dma_prep);
745 
746 /**
747  * geni_se_tx_dma_unprep() - Unprepare the serial engine after TX DMA transfer
748  * @se:			Pointer to the concerned serial engine.
749  * @iova:		DMA address of the TX buffer.
750  * @len:		Length of the TX buffer.
751  *
752  * This function is used to unprepare the DMA buffers after DMA TX.
753  */
754 void geni_se_tx_dma_unprep(struct geni_se *se, dma_addr_t iova, size_t len)
755 {
756 	struct geni_wrapper *wrapper = se->wrapper;
757 
758 	if (!dma_mapping_error(wrapper->dev, iova))
759 		dma_unmap_single(wrapper->dev, iova, len, DMA_TO_DEVICE);
760 }
761 EXPORT_SYMBOL(geni_se_tx_dma_unprep);
762 
763 /**
764  * geni_se_rx_dma_unprep() - Unprepare the serial engine after RX DMA transfer
765  * @se:			Pointer to the concerned serial engine.
766  * @iova:		DMA address of the RX buffer.
767  * @len:		Length of the RX buffer.
768  *
769  * This function is used to unprepare the DMA buffers after DMA RX.
770  */
771 void geni_se_rx_dma_unprep(struct geni_se *se, dma_addr_t iova, size_t len)
772 {
773 	struct geni_wrapper *wrapper = se->wrapper;
774 
775 	if (!dma_mapping_error(wrapper->dev, iova))
776 		dma_unmap_single(wrapper->dev, iova, len, DMA_FROM_DEVICE);
777 }
778 EXPORT_SYMBOL(geni_se_rx_dma_unprep);
779 
780 int geni_icc_get(struct geni_se *se, const char *icc_ddr)
781 {
782 	int i, err;
783 	const char *icc_names[] = {"qup-core", "qup-config", icc_ddr};
784 
785 	if (has_acpi_companion(se->dev))
786 		return 0;
787 
788 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
789 		if (!icc_names[i])
790 			continue;
791 
792 		se->icc_paths[i].path = devm_of_icc_get(se->dev, icc_names[i]);
793 		if (IS_ERR(se->icc_paths[i].path))
794 			goto err;
795 	}
796 
797 	return 0;
798 
799 err:
800 	err = PTR_ERR(se->icc_paths[i].path);
801 	if (err != -EPROBE_DEFER)
802 		dev_err_ratelimited(se->dev, "Failed to get ICC path '%s': %d\n",
803 					icc_names[i], err);
804 	return err;
805 
806 }
807 EXPORT_SYMBOL(geni_icc_get);
808 
809 int geni_icc_set_bw(struct geni_se *se)
810 {
811 	int i, ret;
812 
813 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
814 		ret = icc_set_bw(se->icc_paths[i].path,
815 			se->icc_paths[i].avg_bw, se->icc_paths[i].avg_bw);
816 		if (ret) {
817 			dev_err_ratelimited(se->dev, "ICC BW voting failed on path '%s': %d\n",
818 					icc_path_names[i], ret);
819 			return ret;
820 		}
821 	}
822 
823 	return 0;
824 }
825 EXPORT_SYMBOL(geni_icc_set_bw);
826 
827 void geni_icc_set_tag(struct geni_se *se, u32 tag)
828 {
829 	int i;
830 
831 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++)
832 		icc_set_tag(se->icc_paths[i].path, tag);
833 }
834 EXPORT_SYMBOL(geni_icc_set_tag);
835 
836 /* To do: Replace this by icc_bulk_enable once it's implemented in ICC core */
837 int geni_icc_enable(struct geni_se *se)
838 {
839 	int i, ret;
840 
841 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
842 		ret = icc_enable(se->icc_paths[i].path);
843 		if (ret) {
844 			dev_err_ratelimited(se->dev, "ICC enable failed on path '%s': %d\n",
845 					icc_path_names[i], ret);
846 			return ret;
847 		}
848 	}
849 
850 	return 0;
851 }
852 EXPORT_SYMBOL(geni_icc_enable);
853 
854 int geni_icc_disable(struct geni_se *se)
855 {
856 	int i, ret;
857 
858 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
859 		ret = icc_disable(se->icc_paths[i].path);
860 		if (ret) {
861 			dev_err_ratelimited(se->dev, "ICC disable failed on path '%s': %d\n",
862 					icc_path_names[i], ret);
863 			return ret;
864 		}
865 	}
866 
867 	return 0;
868 }
869 EXPORT_SYMBOL(geni_icc_disable);
870 
871 static int geni_se_probe(struct platform_device *pdev)
872 {
873 	struct device *dev = &pdev->dev;
874 	struct geni_wrapper *wrapper;
875 	int ret;
876 
877 	wrapper = devm_kzalloc(dev, sizeof(*wrapper), GFP_KERNEL);
878 	if (!wrapper)
879 		return -ENOMEM;
880 
881 	wrapper->dev = dev;
882 	wrapper->base = devm_platform_ioremap_resource(pdev, 0);
883 	if (IS_ERR(wrapper->base))
884 		return PTR_ERR(wrapper->base);
885 
886 	if (!has_acpi_companion(&pdev->dev)) {
887 		wrapper->ahb_clks[0].id = "m-ahb";
888 		wrapper->ahb_clks[1].id = "s-ahb";
889 		ret = devm_clk_bulk_get(dev, NUM_AHB_CLKS, wrapper->ahb_clks);
890 		if (ret) {
891 			dev_err(dev, "Err getting AHB clks %d\n", ret);
892 			return ret;
893 		}
894 	}
895 
896 	dev_set_drvdata(dev, wrapper);
897 	dev_dbg(dev, "GENI SE Driver probed\n");
898 	return devm_of_platform_populate(dev);
899 }
900 
901 static const struct of_device_id geni_se_dt_match[] = {
902 	{ .compatible = "qcom,geni-se-qup", },
903 	{}
904 };
905 MODULE_DEVICE_TABLE(of, geni_se_dt_match);
906 
907 static struct platform_driver geni_se_driver = {
908 	.driver = {
909 		.name = "geni_se_qup",
910 		.of_match_table = geni_se_dt_match,
911 	},
912 	.probe = geni_se_probe,
913 };
914 module_platform_driver(geni_se_driver);
915 
916 MODULE_DESCRIPTION("GENI Serial Engine Driver");
917 MODULE_LICENSE("GPL v2");
918