xref: /openbmc/linux/drivers/soc/qcom/qcom-geni-se.c (revision 745b7908)
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  * @to_core:		Core ICC path
93  */
94 struct geni_wrapper {
95 	struct device *dev;
96 	void __iomem *base;
97 	struct clk_bulk_data clks[MAX_CLKS];
98 	unsigned int num_clks;
99 };
100 
101 /**
102  * struct geni_se_desc - Data structure to represent the QUP Wrapper resources
103  * @clks:		Name of the primary & optional secondary AHB clocks
104  * @num_clks:		Count of clock names
105  */
106 struct geni_se_desc {
107 	unsigned int num_clks;
108 	const char * const *clks;
109 };
110 
111 static const char * const icc_path_names[] = {"qup-core", "qup-config",
112 						"qup-memory"};
113 
114 #define QUP_HW_VER_REG			0x4
115 
116 /* Common SE registers */
117 #define GENI_INIT_CFG_REVISION		0x0
118 #define GENI_S_INIT_CFG_REVISION	0x4
119 #define GENI_OUTPUT_CTRL		0x24
120 #define GENI_CGC_CTRL			0x28
121 #define GENI_CLK_CTRL_RO		0x60
122 #define GENI_FW_S_REVISION_RO		0x6c
123 #define SE_GENI_BYTE_GRAN		0x254
124 #define SE_GENI_TX_PACKING_CFG0		0x260
125 #define SE_GENI_TX_PACKING_CFG1		0x264
126 #define SE_GENI_RX_PACKING_CFG0		0x284
127 #define SE_GENI_RX_PACKING_CFG1		0x288
128 #define SE_GENI_M_GP_LENGTH		0x910
129 #define SE_GENI_S_GP_LENGTH		0x914
130 #define SE_DMA_TX_PTR_L			0xc30
131 #define SE_DMA_TX_PTR_H			0xc34
132 #define SE_DMA_TX_ATTR			0xc38
133 #define SE_DMA_TX_LEN			0xc3c
134 #define SE_DMA_TX_IRQ_EN		0xc48
135 #define SE_DMA_TX_IRQ_EN_SET		0xc4c
136 #define SE_DMA_TX_IRQ_EN_CLR		0xc50
137 #define SE_DMA_TX_LEN_IN		0xc54
138 #define SE_DMA_TX_MAX_BURST		0xc5c
139 #define SE_DMA_RX_PTR_L			0xd30
140 #define SE_DMA_RX_PTR_H			0xd34
141 #define SE_DMA_RX_ATTR			0xd38
142 #define SE_DMA_RX_LEN			0xd3c
143 #define SE_DMA_RX_IRQ_EN		0xd48
144 #define SE_DMA_RX_IRQ_EN_SET		0xd4c
145 #define SE_DMA_RX_IRQ_EN_CLR		0xd50
146 #define SE_DMA_RX_LEN_IN		0xd54
147 #define SE_DMA_RX_MAX_BURST		0xd5c
148 #define SE_DMA_RX_FLUSH			0xd60
149 #define SE_GSI_EVENT_EN			0xe18
150 #define SE_IRQ_EN			0xe1c
151 #define SE_DMA_GENERAL_CFG		0xe30
152 
153 /* GENI_OUTPUT_CTRL fields */
154 #define DEFAULT_IO_OUTPUT_CTRL_MSK	GENMASK(6, 0)
155 
156 /* GENI_CGC_CTRL fields */
157 #define CFG_AHB_CLK_CGC_ON		BIT(0)
158 #define CFG_AHB_WR_ACLK_CGC_ON		BIT(1)
159 #define DATA_AHB_CLK_CGC_ON		BIT(2)
160 #define SCLK_CGC_ON			BIT(3)
161 #define TX_CLK_CGC_ON			BIT(4)
162 #define RX_CLK_CGC_ON			BIT(5)
163 #define EXT_CLK_CGC_ON			BIT(6)
164 #define PROG_RAM_HCLK_OFF		BIT(8)
165 #define PROG_RAM_SCLK_OFF		BIT(9)
166 #define DEFAULT_CGC_EN			GENMASK(6, 0)
167 
168 /* SE_GSI_EVENT_EN fields */
169 #define DMA_RX_EVENT_EN			BIT(0)
170 #define DMA_TX_EVENT_EN			BIT(1)
171 #define GENI_M_EVENT_EN			BIT(2)
172 #define GENI_S_EVENT_EN			BIT(3)
173 
174 /* SE_IRQ_EN fields */
175 #define DMA_RX_IRQ_EN			BIT(0)
176 #define DMA_TX_IRQ_EN			BIT(1)
177 #define GENI_M_IRQ_EN			BIT(2)
178 #define GENI_S_IRQ_EN			BIT(3)
179 
180 /* SE_DMA_GENERAL_CFG */
181 #define DMA_RX_CLK_CGC_ON		BIT(0)
182 #define DMA_TX_CLK_CGC_ON		BIT(1)
183 #define DMA_AHB_SLV_CFG_ON		BIT(2)
184 #define AHB_SEC_SLV_CLK_CGC_ON		BIT(3)
185 #define DUMMY_RX_NON_BUFFERABLE		BIT(4)
186 #define RX_DMA_ZERO_PADDING_EN		BIT(5)
187 #define RX_DMA_IRQ_DELAY_MSK		GENMASK(8, 6)
188 #define RX_DMA_IRQ_DELAY_SHFT		6
189 
190 /**
191  * geni_se_get_qup_hw_version() - Read the QUP wrapper Hardware version
192  * @se:	Pointer to the corresponding serial engine.
193  *
194  * Return: Hardware Version of the wrapper.
195  */
196 u32 geni_se_get_qup_hw_version(struct geni_se *se)
197 {
198 	struct geni_wrapper *wrapper = se->wrapper;
199 
200 	return readl_relaxed(wrapper->base + QUP_HW_VER_REG);
201 }
202 EXPORT_SYMBOL(geni_se_get_qup_hw_version);
203 
204 static void geni_se_io_set_mode(void __iomem *base)
205 {
206 	u32 val;
207 
208 	val = readl_relaxed(base + SE_IRQ_EN);
209 	val |= GENI_M_IRQ_EN | GENI_S_IRQ_EN;
210 	val |= DMA_TX_IRQ_EN | DMA_RX_IRQ_EN;
211 	writel_relaxed(val, base + SE_IRQ_EN);
212 
213 	val = readl_relaxed(base + SE_GENI_DMA_MODE_EN);
214 	val &= ~GENI_DMA_MODE_EN;
215 	writel_relaxed(val, base + SE_GENI_DMA_MODE_EN);
216 
217 	writel_relaxed(0, base + SE_GSI_EVENT_EN);
218 }
219 
220 static void geni_se_io_init(void __iomem *base)
221 {
222 	u32 val;
223 
224 	val = readl_relaxed(base + GENI_CGC_CTRL);
225 	val |= DEFAULT_CGC_EN;
226 	writel_relaxed(val, base + GENI_CGC_CTRL);
227 
228 	val = readl_relaxed(base + SE_DMA_GENERAL_CFG);
229 	val |= AHB_SEC_SLV_CLK_CGC_ON | DMA_AHB_SLV_CFG_ON;
230 	val |= DMA_TX_CLK_CGC_ON | DMA_RX_CLK_CGC_ON;
231 	writel_relaxed(val, base + SE_DMA_GENERAL_CFG);
232 
233 	writel_relaxed(DEFAULT_IO_OUTPUT_CTRL_MSK, base + GENI_OUTPUT_CTRL);
234 	writel_relaxed(FORCE_DEFAULT, base + GENI_FORCE_DEFAULT_REG);
235 }
236 
237 static void geni_se_irq_clear(struct geni_se *se)
238 {
239 	writel_relaxed(0, se->base + SE_GSI_EVENT_EN);
240 	writel_relaxed(0xffffffff, se->base + SE_GENI_M_IRQ_CLEAR);
241 	writel_relaxed(0xffffffff, se->base + SE_GENI_S_IRQ_CLEAR);
242 	writel_relaxed(0xffffffff, se->base + SE_DMA_TX_IRQ_CLR);
243 	writel_relaxed(0xffffffff, se->base + SE_DMA_RX_IRQ_CLR);
244 	writel_relaxed(0xffffffff, se->base + SE_IRQ_EN);
245 }
246 
247 /**
248  * geni_se_init() - Initialize the GENI serial engine
249  * @se:		Pointer to the concerned serial engine.
250  * @rx_wm:	Receive watermark, in units of FIFO words.
251  * @rx_rfr:	Ready-for-receive watermark, in units of FIFO words.
252  *
253  * This function is used to initialize the GENI serial engine, configure
254  * receive watermark and ready-for-receive watermarks.
255  */
256 void geni_se_init(struct geni_se *se, u32 rx_wm, u32 rx_rfr)
257 {
258 	u32 val;
259 
260 	geni_se_irq_clear(se);
261 	geni_se_io_init(se->base);
262 	geni_se_io_set_mode(se->base);
263 
264 	writel_relaxed(rx_wm, se->base + SE_GENI_RX_WATERMARK_REG);
265 	writel_relaxed(rx_rfr, se->base + SE_GENI_RX_RFR_WATERMARK_REG);
266 
267 	val = readl_relaxed(se->base + SE_GENI_M_IRQ_EN);
268 	val |= M_COMMON_GENI_M_IRQ_EN;
269 	writel_relaxed(val, se->base + SE_GENI_M_IRQ_EN);
270 
271 	val = readl_relaxed(se->base + SE_GENI_S_IRQ_EN);
272 	val |= S_COMMON_GENI_S_IRQ_EN;
273 	writel_relaxed(val, se->base + SE_GENI_S_IRQ_EN);
274 }
275 EXPORT_SYMBOL(geni_se_init);
276 
277 static void geni_se_select_fifo_mode(struct geni_se *se)
278 {
279 	u32 proto = geni_se_read_proto(se);
280 	u32 val, val_old;
281 
282 	geni_se_irq_clear(se);
283 
284 	/*
285 	 * The RX path for the UART is asynchronous and so needs more
286 	 * complex logic for enabling / disabling its interrupts.
287 	 *
288 	 * Specific notes:
289 	 * - The done and TX-related interrupts are managed manually.
290 	 * - We don't RX from the main sequencer (we use the secondary) so
291 	 *   we don't need the RX-related interrupts enabled in the main
292 	 *   sequencer for UART.
293 	 */
294 	if (proto != GENI_SE_UART) {
295 		val_old = val = readl_relaxed(se->base + SE_GENI_M_IRQ_EN);
296 		val |= M_CMD_DONE_EN | M_TX_FIFO_WATERMARK_EN;
297 		val |= M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN;
298 		if (val != val_old)
299 			writel_relaxed(val, se->base + SE_GENI_M_IRQ_EN);
300 
301 		val_old = val = readl_relaxed(se->base + SE_GENI_S_IRQ_EN);
302 		val |= S_CMD_DONE_EN;
303 		if (val != val_old)
304 			writel_relaxed(val, se->base + SE_GENI_S_IRQ_EN);
305 	}
306 
307 	val_old = val = readl_relaxed(se->base + SE_GENI_DMA_MODE_EN);
308 	val &= ~GENI_DMA_MODE_EN;
309 	if (val != val_old)
310 		writel_relaxed(val, se->base + SE_GENI_DMA_MODE_EN);
311 }
312 
313 static void geni_se_select_dma_mode(struct geni_se *se)
314 {
315 	u32 proto = geni_se_read_proto(se);
316 	u32 val, val_old;
317 
318 	geni_se_irq_clear(se);
319 
320 	if (proto != GENI_SE_UART) {
321 		val_old = val = readl_relaxed(se->base + SE_GENI_M_IRQ_EN);
322 		val &= ~(M_CMD_DONE_EN | M_TX_FIFO_WATERMARK_EN);
323 		val &= ~(M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN);
324 		if (val != val_old)
325 			writel_relaxed(val, se->base + SE_GENI_M_IRQ_EN);
326 
327 		val_old = val = readl_relaxed(se->base + SE_GENI_S_IRQ_EN);
328 		val &= ~S_CMD_DONE_EN;
329 		if (val != val_old)
330 			writel_relaxed(val, se->base + SE_GENI_S_IRQ_EN);
331 	}
332 
333 	val_old = val = readl_relaxed(se->base + SE_GENI_DMA_MODE_EN);
334 	val |= GENI_DMA_MODE_EN;
335 	if (val != val_old)
336 		writel_relaxed(val, se->base + SE_GENI_DMA_MODE_EN);
337 }
338 
339 static void geni_se_select_gpi_mode(struct geni_se *se)
340 {
341 	u32 val;
342 
343 	geni_se_irq_clear(se);
344 
345 	writel(0, se->base + SE_IRQ_EN);
346 
347 	val = readl(se->base + SE_GENI_S_IRQ_EN);
348 	val &= ~S_CMD_DONE_EN;
349 	writel(val, se->base + SE_GENI_S_IRQ_EN);
350 
351 	val = readl(se->base + SE_GENI_M_IRQ_EN);
352 	val &= ~(M_CMD_DONE_EN | M_TX_FIFO_WATERMARK_EN |
353 		 M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN);
354 	writel(val, se->base + SE_GENI_M_IRQ_EN);
355 
356 	writel(GENI_DMA_MODE_EN, se->base + SE_GENI_DMA_MODE_EN);
357 
358 	val = readl(se->base + SE_GSI_EVENT_EN);
359 	val |= (DMA_RX_EVENT_EN | DMA_TX_EVENT_EN | GENI_M_EVENT_EN | GENI_S_EVENT_EN);
360 	writel(val, se->base + SE_GSI_EVENT_EN);
361 }
362 
363 /**
364  * geni_se_select_mode() - Select the serial engine transfer mode
365  * @se:		Pointer to the concerned serial engine.
366  * @mode:	Transfer mode to be selected.
367  */
368 void geni_se_select_mode(struct geni_se *se, enum geni_se_xfer_mode mode)
369 {
370 	WARN_ON(mode != GENI_SE_FIFO && mode != GENI_SE_DMA && mode != GENI_GPI_DMA);
371 
372 	switch (mode) {
373 	case GENI_SE_FIFO:
374 		geni_se_select_fifo_mode(se);
375 		break;
376 	case GENI_SE_DMA:
377 		geni_se_select_dma_mode(se);
378 		break;
379 	case GENI_GPI_DMA:
380 		geni_se_select_gpi_mode(se);
381 		break;
382 	case GENI_SE_INVALID:
383 	default:
384 		break;
385 	}
386 }
387 EXPORT_SYMBOL(geni_se_select_mode);
388 
389 /**
390  * DOC: Overview
391  *
392  * GENI FIFO packing is highly configurable. TX/RX packing/unpacking consist
393  * of up to 4 operations, each operation represented by 4 configuration vectors
394  * of 10 bits programmed in GENI_TX_PACKING_CFG0 and GENI_TX_PACKING_CFG1 for
395  * TX FIFO and in GENI_RX_PACKING_CFG0 and GENI_RX_PACKING_CFG1 for RX FIFO.
396  * Refer to below examples for detailed bit-field description.
397  *
398  * Example 1: word_size = 7, packing_mode = 4 x 8, msb_to_lsb = 1
399  *
400  *        +-----------+-------+-------+-------+-------+
401  *        |           | vec_0 | vec_1 | vec_2 | vec_3 |
402  *        +-----------+-------+-------+-------+-------+
403  *        | start     | 0x6   | 0xe   | 0x16  | 0x1e  |
404  *        | direction | 1     | 1     | 1     | 1     |
405  *        | length    | 6     | 6     | 6     | 6     |
406  *        | stop      | 0     | 0     | 0     | 1     |
407  *        +-----------+-------+-------+-------+-------+
408  *
409  * Example 2: word_size = 15, packing_mode = 2 x 16, msb_to_lsb = 0
410  *
411  *        +-----------+-------+-------+-------+-------+
412  *        |           | vec_0 | vec_1 | vec_2 | vec_3 |
413  *        +-----------+-------+-------+-------+-------+
414  *        | start     | 0x0   | 0x8   | 0x10  | 0x18  |
415  *        | direction | 0     | 0     | 0     | 0     |
416  *        | length    | 7     | 6     | 7     | 6     |
417  *        | stop      | 0     | 0     | 0     | 1     |
418  *        +-----------+-------+-------+-------+-------+
419  *
420  * Example 3: word_size = 23, packing_mode = 1 x 32, msb_to_lsb = 1
421  *
422  *        +-----------+-------+-------+-------+-------+
423  *        |           | vec_0 | vec_1 | vec_2 | vec_3 |
424  *        +-----------+-------+-------+-------+-------+
425  *        | start     | 0x16  | 0xe   | 0x6   | 0x0   |
426  *        | direction | 1     | 1     | 1     | 1     |
427  *        | length    | 7     | 7     | 6     | 0     |
428  *        | stop      | 0     | 0     | 1     | 0     |
429  *        +-----------+-------+-------+-------+-------+
430  *
431  */
432 
433 #define NUM_PACKING_VECTORS 4
434 #define PACKING_START_SHIFT 5
435 #define PACKING_DIR_SHIFT 4
436 #define PACKING_LEN_SHIFT 1
437 #define PACKING_STOP_BIT BIT(0)
438 #define PACKING_VECTOR_SHIFT 10
439 /**
440  * geni_se_config_packing() - Packing configuration of the serial engine
441  * @se:		Pointer to the concerned serial engine
442  * @bpw:	Bits of data per transfer word.
443  * @pack_words:	Number of words per fifo element.
444  * @msb_to_lsb:	Transfer from MSB to LSB or vice-versa.
445  * @tx_cfg:	Flag to configure the TX Packing.
446  * @rx_cfg:	Flag to configure the RX Packing.
447  *
448  * This function is used to configure the packing rules for the current
449  * transfer.
450  */
451 void geni_se_config_packing(struct geni_se *se, int bpw, int pack_words,
452 			    bool msb_to_lsb, bool tx_cfg, bool rx_cfg)
453 {
454 	u32 cfg0, cfg1, cfg[NUM_PACKING_VECTORS] = {0};
455 	int len;
456 	int temp_bpw = bpw;
457 	int idx_start = msb_to_lsb ? bpw - 1 : 0;
458 	int idx = idx_start;
459 	int idx_delta = msb_to_lsb ? -BITS_PER_BYTE : BITS_PER_BYTE;
460 	int ceil_bpw = ALIGN(bpw, BITS_PER_BYTE);
461 	int iter = (ceil_bpw * pack_words) / BITS_PER_BYTE;
462 	int i;
463 
464 	if (iter <= 0 || iter > NUM_PACKING_VECTORS)
465 		return;
466 
467 	for (i = 0; i < iter; i++) {
468 		len = min_t(int, temp_bpw, BITS_PER_BYTE) - 1;
469 		cfg[i] = idx << PACKING_START_SHIFT;
470 		cfg[i] |= msb_to_lsb << PACKING_DIR_SHIFT;
471 		cfg[i] |= len << PACKING_LEN_SHIFT;
472 
473 		if (temp_bpw <= BITS_PER_BYTE) {
474 			idx = ((i + 1) * BITS_PER_BYTE) + idx_start;
475 			temp_bpw = bpw;
476 		} else {
477 			idx = idx + idx_delta;
478 			temp_bpw = temp_bpw - BITS_PER_BYTE;
479 		}
480 	}
481 	cfg[iter - 1] |= PACKING_STOP_BIT;
482 	cfg0 = cfg[0] | (cfg[1] << PACKING_VECTOR_SHIFT);
483 	cfg1 = cfg[2] | (cfg[3] << PACKING_VECTOR_SHIFT);
484 
485 	if (tx_cfg) {
486 		writel_relaxed(cfg0, se->base + SE_GENI_TX_PACKING_CFG0);
487 		writel_relaxed(cfg1, se->base + SE_GENI_TX_PACKING_CFG1);
488 	}
489 	if (rx_cfg) {
490 		writel_relaxed(cfg0, se->base + SE_GENI_RX_PACKING_CFG0);
491 		writel_relaxed(cfg1, se->base + SE_GENI_RX_PACKING_CFG1);
492 	}
493 
494 	/*
495 	 * Number of protocol words in each FIFO entry
496 	 * 0 - 4x8, four words in each entry, max word size of 8 bits
497 	 * 1 - 2x16, two words in each entry, max word size of 16 bits
498 	 * 2 - 1x32, one word in each entry, max word size of 32 bits
499 	 * 3 - undefined
500 	 */
501 	if (pack_words || bpw == 32)
502 		writel_relaxed(bpw / 16, se->base + SE_GENI_BYTE_GRAN);
503 }
504 EXPORT_SYMBOL(geni_se_config_packing);
505 
506 static void geni_se_clks_off(struct geni_se *se)
507 {
508 	struct geni_wrapper *wrapper = se->wrapper;
509 
510 	clk_disable_unprepare(se->clk);
511 	clk_bulk_disable_unprepare(wrapper->num_clks, wrapper->clks);
512 }
513 
514 /**
515  * geni_se_resources_off() - Turn off resources associated with the serial
516  *                           engine
517  * @se:	Pointer to the concerned serial engine.
518  *
519  * Return: 0 on success, standard Linux error codes on failure/error.
520  */
521 int geni_se_resources_off(struct geni_se *se)
522 {
523 	int ret;
524 
525 	if (has_acpi_companion(se->dev))
526 		return 0;
527 
528 	ret = pinctrl_pm_select_sleep_state(se->dev);
529 	if (ret)
530 		return ret;
531 
532 	geni_se_clks_off(se);
533 	return 0;
534 }
535 EXPORT_SYMBOL(geni_se_resources_off);
536 
537 static int geni_se_clks_on(struct geni_se *se)
538 {
539 	int ret;
540 	struct geni_wrapper *wrapper = se->wrapper;
541 
542 	ret = clk_bulk_prepare_enable(wrapper->num_clks, wrapper->clks);
543 	if (ret)
544 		return ret;
545 
546 	ret = clk_prepare_enable(se->clk);
547 	if (ret)
548 		clk_bulk_disable_unprepare(wrapper->num_clks, wrapper->clks);
549 	return ret;
550 }
551 
552 /**
553  * geni_se_resources_on() - Turn on resources associated with the serial
554  *                          engine
555  * @se:	Pointer to the concerned serial engine.
556  *
557  * Return: 0 on success, standard Linux error codes on failure/error.
558  */
559 int geni_se_resources_on(struct geni_se *se)
560 {
561 	int ret;
562 
563 	if (has_acpi_companion(se->dev))
564 		return 0;
565 
566 	ret = geni_se_clks_on(se);
567 	if (ret)
568 		return ret;
569 
570 	ret = pinctrl_pm_select_default_state(se->dev);
571 	if (ret)
572 		geni_se_clks_off(se);
573 
574 	return ret;
575 }
576 EXPORT_SYMBOL(geni_se_resources_on);
577 
578 /**
579  * geni_se_clk_tbl_get() - Get the clock table to program DFS
580  * @se:		Pointer to the concerned serial engine.
581  * @tbl:	Table in which the output is returned.
582  *
583  * This function is called by the protocol drivers to determine the different
584  * clock frequencies supported by serial engine core clock. The protocol
585  * drivers use the output to determine the clock frequency index to be
586  * programmed into DFS.
587  *
588  * Return: number of valid performance levels in the table on success,
589  *	   standard Linux error codes on failure.
590  */
591 int geni_se_clk_tbl_get(struct geni_se *se, unsigned long **tbl)
592 {
593 	long freq = 0;
594 	int i;
595 
596 	if (se->clk_perf_tbl) {
597 		*tbl = se->clk_perf_tbl;
598 		return se->num_clk_levels;
599 	}
600 
601 	se->clk_perf_tbl = devm_kcalloc(se->dev, MAX_CLK_PERF_LEVEL,
602 					sizeof(*se->clk_perf_tbl),
603 					GFP_KERNEL);
604 	if (!se->clk_perf_tbl)
605 		return -ENOMEM;
606 
607 	for (i = 0; i < MAX_CLK_PERF_LEVEL; i++) {
608 		freq = clk_round_rate(se->clk, freq + 1);
609 		if (freq <= 0 || freq == se->clk_perf_tbl[i - 1])
610 			break;
611 		se->clk_perf_tbl[i] = freq;
612 	}
613 	se->num_clk_levels = i;
614 	*tbl = se->clk_perf_tbl;
615 	return se->num_clk_levels;
616 }
617 EXPORT_SYMBOL(geni_se_clk_tbl_get);
618 
619 /**
620  * geni_se_clk_freq_match() - Get the matching or closest SE clock frequency
621  * @se:		Pointer to the concerned serial engine.
622  * @req_freq:	Requested clock frequency.
623  * @index:	Index of the resultant frequency in the table.
624  * @res_freq:	Resultant frequency of the source clock.
625  * @exact:	Flag to indicate exact multiple requirement of the requested
626  *		frequency.
627  *
628  * This function is called by the protocol drivers to determine the best match
629  * of the requested frequency as provided by the serial engine clock in order
630  * to meet the performance requirements.
631  *
632  * If we return success:
633  * - if @exact is true  then @res_freq / <an_integer> == @req_freq
634  * - if @exact is false then @res_freq / <an_integer> <= @req_freq
635  *
636  * Return: 0 on success, standard Linux error codes on failure.
637  */
638 int geni_se_clk_freq_match(struct geni_se *se, unsigned long req_freq,
639 			   unsigned int *index, unsigned long *res_freq,
640 			   bool exact)
641 {
642 	unsigned long *tbl;
643 	int num_clk_levels;
644 	int i;
645 	unsigned long best_delta;
646 	unsigned long new_delta;
647 	unsigned int divider;
648 
649 	num_clk_levels = geni_se_clk_tbl_get(se, &tbl);
650 	if (num_clk_levels < 0)
651 		return num_clk_levels;
652 
653 	if (num_clk_levels == 0)
654 		return -EINVAL;
655 
656 	best_delta = ULONG_MAX;
657 	for (i = 0; i < num_clk_levels; i++) {
658 		divider = DIV_ROUND_UP(tbl[i], req_freq);
659 		new_delta = req_freq - tbl[i] / divider;
660 		if (new_delta < best_delta) {
661 			/* We have a new best! */
662 			*index = i;
663 			*res_freq = tbl[i];
664 
665 			/* If the new best is exact then we're done */
666 			if (new_delta == 0)
667 				return 0;
668 
669 			/* Record how close we got */
670 			best_delta = new_delta;
671 		}
672 	}
673 
674 	if (exact)
675 		return -EINVAL;
676 
677 	return 0;
678 }
679 EXPORT_SYMBOL(geni_se_clk_freq_match);
680 
681 #define GENI_SE_DMA_DONE_EN BIT(0)
682 #define GENI_SE_DMA_EOT_EN BIT(1)
683 #define GENI_SE_DMA_AHB_ERR_EN BIT(2)
684 #define GENI_SE_DMA_EOT_BUF BIT(0)
685 /**
686  * geni_se_tx_dma_prep() - Prepare the serial engine for TX DMA transfer
687  * @se:			Pointer to the concerned serial engine.
688  * @buf:		Pointer to the TX buffer.
689  * @len:		Length of the TX buffer.
690  * @iova:		Pointer to store the mapped DMA address.
691  *
692  * This function is used to prepare the buffers for DMA TX.
693  *
694  * Return: 0 on success, standard Linux error codes on failure.
695  */
696 int geni_se_tx_dma_prep(struct geni_se *se, void *buf, size_t len,
697 			dma_addr_t *iova)
698 {
699 	struct geni_wrapper *wrapper = se->wrapper;
700 	u32 val;
701 
702 	if (!wrapper)
703 		return -EINVAL;
704 
705 	*iova = dma_map_single(wrapper->dev, buf, len, DMA_TO_DEVICE);
706 	if (dma_mapping_error(wrapper->dev, *iova))
707 		return -EIO;
708 
709 	val = GENI_SE_DMA_DONE_EN;
710 	val |= GENI_SE_DMA_EOT_EN;
711 	val |= GENI_SE_DMA_AHB_ERR_EN;
712 	writel_relaxed(val, se->base + SE_DMA_TX_IRQ_EN_SET);
713 	writel_relaxed(lower_32_bits(*iova), se->base + SE_DMA_TX_PTR_L);
714 	writel_relaxed(upper_32_bits(*iova), se->base + SE_DMA_TX_PTR_H);
715 	writel_relaxed(GENI_SE_DMA_EOT_BUF, se->base + SE_DMA_TX_ATTR);
716 	writel(len, se->base + SE_DMA_TX_LEN);
717 	return 0;
718 }
719 EXPORT_SYMBOL(geni_se_tx_dma_prep);
720 
721 /**
722  * geni_se_rx_dma_prep() - Prepare the serial engine for RX DMA transfer
723  * @se:			Pointer to the concerned serial engine.
724  * @buf:		Pointer to the RX buffer.
725  * @len:		Length of the RX buffer.
726  * @iova:		Pointer to store the mapped DMA address.
727  *
728  * This function is used to prepare the buffers for DMA RX.
729  *
730  * Return: 0 on success, standard Linux error codes on failure.
731  */
732 int geni_se_rx_dma_prep(struct geni_se *se, void *buf, size_t len,
733 			dma_addr_t *iova)
734 {
735 	struct geni_wrapper *wrapper = se->wrapper;
736 	u32 val;
737 
738 	if (!wrapper)
739 		return -EINVAL;
740 
741 	*iova = dma_map_single(wrapper->dev, buf, len, DMA_FROM_DEVICE);
742 	if (dma_mapping_error(wrapper->dev, *iova))
743 		return -EIO;
744 
745 	val = GENI_SE_DMA_DONE_EN;
746 	val |= GENI_SE_DMA_EOT_EN;
747 	val |= GENI_SE_DMA_AHB_ERR_EN;
748 	writel_relaxed(val, se->base + SE_DMA_RX_IRQ_EN_SET);
749 	writel_relaxed(lower_32_bits(*iova), se->base + SE_DMA_RX_PTR_L);
750 	writel_relaxed(upper_32_bits(*iova), se->base + SE_DMA_RX_PTR_H);
751 	/* RX does not have EOT buffer type bit. So just reset RX_ATTR */
752 	writel_relaxed(0, se->base + SE_DMA_RX_ATTR);
753 	writel(len, se->base + SE_DMA_RX_LEN);
754 	return 0;
755 }
756 EXPORT_SYMBOL(geni_se_rx_dma_prep);
757 
758 /**
759  * geni_se_tx_dma_unprep() - Unprepare the serial engine after TX DMA transfer
760  * @se:			Pointer to the concerned serial engine.
761  * @iova:		DMA address of the TX buffer.
762  * @len:		Length of the TX buffer.
763  *
764  * This function is used to unprepare the DMA buffers after DMA TX.
765  */
766 void geni_se_tx_dma_unprep(struct geni_se *se, dma_addr_t iova, size_t len)
767 {
768 	struct geni_wrapper *wrapper = se->wrapper;
769 
770 	if (!dma_mapping_error(wrapper->dev, iova))
771 		dma_unmap_single(wrapper->dev, iova, len, DMA_TO_DEVICE);
772 }
773 EXPORT_SYMBOL(geni_se_tx_dma_unprep);
774 
775 /**
776  * geni_se_rx_dma_unprep() - Unprepare the serial engine after RX DMA transfer
777  * @se:			Pointer to the concerned serial engine.
778  * @iova:		DMA address of the RX buffer.
779  * @len:		Length of the RX buffer.
780  *
781  * This function is used to unprepare the DMA buffers after DMA RX.
782  */
783 void geni_se_rx_dma_unprep(struct geni_se *se, dma_addr_t iova, size_t len)
784 {
785 	struct geni_wrapper *wrapper = se->wrapper;
786 
787 	if (!dma_mapping_error(wrapper->dev, iova))
788 		dma_unmap_single(wrapper->dev, iova, len, DMA_FROM_DEVICE);
789 }
790 EXPORT_SYMBOL(geni_se_rx_dma_unprep);
791 
792 int geni_icc_get(struct geni_se *se, const char *icc_ddr)
793 {
794 	int i, err;
795 	const char *icc_names[] = {"qup-core", "qup-config", icc_ddr};
796 
797 	if (has_acpi_companion(se->dev))
798 		return 0;
799 
800 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
801 		if (!icc_names[i])
802 			continue;
803 
804 		se->icc_paths[i].path = devm_of_icc_get(se->dev, icc_names[i]);
805 		if (IS_ERR(se->icc_paths[i].path))
806 			goto err;
807 	}
808 
809 	return 0;
810 
811 err:
812 	err = PTR_ERR(se->icc_paths[i].path);
813 	if (err != -EPROBE_DEFER)
814 		dev_err_ratelimited(se->dev, "Failed to get ICC path '%s': %d\n",
815 					icc_names[i], err);
816 	return err;
817 
818 }
819 EXPORT_SYMBOL(geni_icc_get);
820 
821 int geni_icc_set_bw(struct geni_se *se)
822 {
823 	int i, ret;
824 
825 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
826 		ret = icc_set_bw(se->icc_paths[i].path,
827 			se->icc_paths[i].avg_bw, se->icc_paths[i].avg_bw);
828 		if (ret) {
829 			dev_err_ratelimited(se->dev, "ICC BW voting failed on path '%s': %d\n",
830 					icc_path_names[i], ret);
831 			return ret;
832 		}
833 	}
834 
835 	return 0;
836 }
837 EXPORT_SYMBOL(geni_icc_set_bw);
838 
839 void geni_icc_set_tag(struct geni_se *se, u32 tag)
840 {
841 	int i;
842 
843 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++)
844 		icc_set_tag(se->icc_paths[i].path, tag);
845 }
846 EXPORT_SYMBOL(geni_icc_set_tag);
847 
848 /* To do: Replace this by icc_bulk_enable once it's implemented in ICC core */
849 int geni_icc_enable(struct geni_se *se)
850 {
851 	int i, ret;
852 
853 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
854 		ret = icc_enable(se->icc_paths[i].path);
855 		if (ret) {
856 			dev_err_ratelimited(se->dev, "ICC enable failed on path '%s': %d\n",
857 					icc_path_names[i], ret);
858 			return ret;
859 		}
860 	}
861 
862 	return 0;
863 }
864 EXPORT_SYMBOL(geni_icc_enable);
865 
866 int geni_icc_disable(struct geni_se *se)
867 {
868 	int i, ret;
869 
870 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
871 		ret = icc_disable(se->icc_paths[i].path);
872 		if (ret) {
873 			dev_err_ratelimited(se->dev, "ICC disable failed on path '%s': %d\n",
874 					icc_path_names[i], ret);
875 			return ret;
876 		}
877 	}
878 
879 	return 0;
880 }
881 EXPORT_SYMBOL(geni_icc_disable);
882 
883 static int geni_se_probe(struct platform_device *pdev)
884 {
885 	struct device *dev = &pdev->dev;
886 	struct geni_wrapper *wrapper;
887 	int ret;
888 
889 	wrapper = devm_kzalloc(dev, sizeof(*wrapper), GFP_KERNEL);
890 	if (!wrapper)
891 		return -ENOMEM;
892 
893 	wrapper->dev = dev;
894 	wrapper->base = devm_platform_ioremap_resource(pdev, 0);
895 	if (IS_ERR(wrapper->base))
896 		return PTR_ERR(wrapper->base);
897 
898 	if (!has_acpi_companion(&pdev->dev)) {
899 		const struct geni_se_desc *desc;
900 		int i;
901 
902 		desc = device_get_match_data(&pdev->dev);
903 		if (!desc)
904 			return -EINVAL;
905 
906 		wrapper->num_clks = min_t(unsigned int, desc->num_clks, MAX_CLKS);
907 
908 		for (i = 0; i < wrapper->num_clks; ++i)
909 			wrapper->clks[i].id = desc->clks[i];
910 
911 		ret = of_count_phandle_with_args(dev->of_node, "clocks", "#clock-cells");
912 		if (ret < 0) {
913 			dev_err(dev, "invalid clocks property at %pOF\n", dev->of_node);
914 			return ret;
915 		}
916 
917 		if (ret < wrapper->num_clks) {
918 			dev_err(dev, "invalid clocks count at %pOF, expected %d entries\n",
919 				dev->of_node, wrapper->num_clks);
920 			return -EINVAL;
921 		}
922 
923 		ret = devm_clk_bulk_get(dev, wrapper->num_clks, wrapper->clks);
924 		if (ret) {
925 			dev_err(dev, "Err getting clks %d\n", ret);
926 			return ret;
927 		}
928 	}
929 
930 	dev_set_drvdata(dev, wrapper);
931 	dev_dbg(dev, "GENI SE Driver probed\n");
932 	return devm_of_platform_populate(dev);
933 }
934 
935 static const char * const qup_clks[] = {
936 	"m-ahb",
937 	"s-ahb",
938 };
939 
940 static const struct geni_se_desc qup_desc = {
941 	.clks = qup_clks,
942 	.num_clks = ARRAY_SIZE(qup_clks),
943 };
944 
945 static const char * const i2c_master_hub_clks[] = {
946 	"s-ahb",
947 };
948 
949 static const struct geni_se_desc i2c_master_hub_desc = {
950 	.clks = i2c_master_hub_clks,
951 	.num_clks = ARRAY_SIZE(i2c_master_hub_clks),
952 };
953 
954 static const struct of_device_id geni_se_dt_match[] = {
955 	{ .compatible = "qcom,geni-se-qup", .data = &qup_desc },
956 	{ .compatible = "qcom,geni-se-i2c-master-hub", .data = &i2c_master_hub_desc },
957 	{}
958 };
959 MODULE_DEVICE_TABLE(of, geni_se_dt_match);
960 
961 static struct platform_driver geni_se_driver = {
962 	.driver = {
963 		.name = "geni_se_qup",
964 		.of_match_table = geni_se_dt_match,
965 	},
966 	.probe = geni_se_probe,
967 };
968 module_platform_driver(geni_se_driver);
969 
970 MODULE_DESCRIPTION("GENI Serial Engine Driver");
971 MODULE_LICENSE("GPL v2");
972