xref: /openbmc/linux/drivers/soc/qcom/qcom-geni-se.c (revision 5d85ea2c)
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 	/* UART driver manages enabling / disabling interrupts internally */
285 	if (proto != GENI_SE_UART) {
286 		/* Non-UART use only primary sequencer so dont bother about S_IRQ */
287 		val_old = val = readl_relaxed(se->base + SE_GENI_M_IRQ_EN);
288 		val |= M_CMD_DONE_EN | M_TX_FIFO_WATERMARK_EN;
289 		val |= M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN;
290 		if (val != val_old)
291 			writel_relaxed(val, se->base + SE_GENI_M_IRQ_EN);
292 	}
293 
294 	val_old = val = readl_relaxed(se->base + SE_GENI_DMA_MODE_EN);
295 	val &= ~GENI_DMA_MODE_EN;
296 	if (val != val_old)
297 		writel_relaxed(val, se->base + SE_GENI_DMA_MODE_EN);
298 }
299 
300 static void geni_se_select_dma_mode(struct geni_se *se)
301 {
302 	u32 proto = geni_se_read_proto(se);
303 	u32 val, val_old;
304 
305 	geni_se_irq_clear(se);
306 
307 	/* UART driver manages enabling / disabling interrupts internally */
308 	if (proto != GENI_SE_UART) {
309 		/* Non-UART use only primary sequencer so dont bother about S_IRQ */
310 		val_old = val = readl_relaxed(se->base + SE_GENI_M_IRQ_EN);
311 		val &= ~(M_CMD_DONE_EN | M_TX_FIFO_WATERMARK_EN);
312 		val &= ~(M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN);
313 		if (val != val_old)
314 			writel_relaxed(val, se->base + SE_GENI_M_IRQ_EN);
315 	}
316 
317 	val_old = val = readl_relaxed(se->base + SE_GENI_DMA_MODE_EN);
318 	val |= GENI_DMA_MODE_EN;
319 	if (val != val_old)
320 		writel_relaxed(val, se->base + SE_GENI_DMA_MODE_EN);
321 }
322 
323 static void geni_se_select_gpi_mode(struct geni_se *se)
324 {
325 	u32 val;
326 
327 	geni_se_irq_clear(se);
328 
329 	writel(0, se->base + SE_IRQ_EN);
330 
331 	val = readl(se->base + SE_GENI_M_IRQ_EN);
332 	val &= ~(M_CMD_DONE_EN | M_TX_FIFO_WATERMARK_EN |
333 		 M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN);
334 	writel(val, se->base + SE_GENI_M_IRQ_EN);
335 
336 	writel(GENI_DMA_MODE_EN, se->base + SE_GENI_DMA_MODE_EN);
337 
338 	val = readl(se->base + SE_GSI_EVENT_EN);
339 	val |= (DMA_RX_EVENT_EN | DMA_TX_EVENT_EN | GENI_M_EVENT_EN | GENI_S_EVENT_EN);
340 	writel(val, se->base + SE_GSI_EVENT_EN);
341 }
342 
343 /**
344  * geni_se_select_mode() - Select the serial engine transfer mode
345  * @se:		Pointer to the concerned serial engine.
346  * @mode:	Transfer mode to be selected.
347  */
348 void geni_se_select_mode(struct geni_se *se, enum geni_se_xfer_mode mode)
349 {
350 	WARN_ON(mode != GENI_SE_FIFO && mode != GENI_SE_DMA && mode != GENI_GPI_DMA);
351 
352 	switch (mode) {
353 	case GENI_SE_FIFO:
354 		geni_se_select_fifo_mode(se);
355 		break;
356 	case GENI_SE_DMA:
357 		geni_se_select_dma_mode(se);
358 		break;
359 	case GENI_GPI_DMA:
360 		geni_se_select_gpi_mode(se);
361 		break;
362 	case GENI_SE_INVALID:
363 	default:
364 		break;
365 	}
366 }
367 EXPORT_SYMBOL(geni_se_select_mode);
368 
369 /**
370  * DOC: Overview
371  *
372  * GENI FIFO packing is highly configurable. TX/RX packing/unpacking consist
373  * of up to 4 operations, each operation represented by 4 configuration vectors
374  * of 10 bits programmed in GENI_TX_PACKING_CFG0 and GENI_TX_PACKING_CFG1 for
375  * TX FIFO and in GENI_RX_PACKING_CFG0 and GENI_RX_PACKING_CFG1 for RX FIFO.
376  * Refer to below examples for detailed bit-field description.
377  *
378  * Example 1: word_size = 7, packing_mode = 4 x 8, msb_to_lsb = 1
379  *
380  *        +-----------+-------+-------+-------+-------+
381  *        |           | vec_0 | vec_1 | vec_2 | vec_3 |
382  *        +-----------+-------+-------+-------+-------+
383  *        | start     | 0x6   | 0xe   | 0x16  | 0x1e  |
384  *        | direction | 1     | 1     | 1     | 1     |
385  *        | length    | 6     | 6     | 6     | 6     |
386  *        | stop      | 0     | 0     | 0     | 1     |
387  *        +-----------+-------+-------+-------+-------+
388  *
389  * Example 2: word_size = 15, packing_mode = 2 x 16, msb_to_lsb = 0
390  *
391  *        +-----------+-------+-------+-------+-------+
392  *        |           | vec_0 | vec_1 | vec_2 | vec_3 |
393  *        +-----------+-------+-------+-------+-------+
394  *        | start     | 0x0   | 0x8   | 0x10  | 0x18  |
395  *        | direction | 0     | 0     | 0     | 0     |
396  *        | length    | 7     | 6     | 7     | 6     |
397  *        | stop      | 0     | 0     | 0     | 1     |
398  *        +-----------+-------+-------+-------+-------+
399  *
400  * Example 3: word_size = 23, packing_mode = 1 x 32, msb_to_lsb = 1
401  *
402  *        +-----------+-------+-------+-------+-------+
403  *        |           | vec_0 | vec_1 | vec_2 | vec_3 |
404  *        +-----------+-------+-------+-------+-------+
405  *        | start     | 0x16  | 0xe   | 0x6   | 0x0   |
406  *        | direction | 1     | 1     | 1     | 1     |
407  *        | length    | 7     | 7     | 6     | 0     |
408  *        | stop      | 0     | 0     | 1     | 0     |
409  *        +-----------+-------+-------+-------+-------+
410  *
411  */
412 
413 #define NUM_PACKING_VECTORS 4
414 #define PACKING_START_SHIFT 5
415 #define PACKING_DIR_SHIFT 4
416 #define PACKING_LEN_SHIFT 1
417 #define PACKING_STOP_BIT BIT(0)
418 #define PACKING_VECTOR_SHIFT 10
419 /**
420  * geni_se_config_packing() - Packing configuration of the serial engine
421  * @se:		Pointer to the concerned serial engine
422  * @bpw:	Bits of data per transfer word.
423  * @pack_words:	Number of words per fifo element.
424  * @msb_to_lsb:	Transfer from MSB to LSB or vice-versa.
425  * @tx_cfg:	Flag to configure the TX Packing.
426  * @rx_cfg:	Flag to configure the RX Packing.
427  *
428  * This function is used to configure the packing rules for the current
429  * transfer.
430  */
431 void geni_se_config_packing(struct geni_se *se, int bpw, int pack_words,
432 			    bool msb_to_lsb, bool tx_cfg, bool rx_cfg)
433 {
434 	u32 cfg0, cfg1, cfg[NUM_PACKING_VECTORS] = {0};
435 	int len;
436 	int temp_bpw = bpw;
437 	int idx_start = msb_to_lsb ? bpw - 1 : 0;
438 	int idx = idx_start;
439 	int idx_delta = msb_to_lsb ? -BITS_PER_BYTE : BITS_PER_BYTE;
440 	int ceil_bpw = ALIGN(bpw, BITS_PER_BYTE);
441 	int iter = (ceil_bpw * pack_words) / BITS_PER_BYTE;
442 	int i;
443 
444 	if (iter <= 0 || iter > NUM_PACKING_VECTORS)
445 		return;
446 
447 	for (i = 0; i < iter; i++) {
448 		len = min_t(int, temp_bpw, BITS_PER_BYTE) - 1;
449 		cfg[i] = idx << PACKING_START_SHIFT;
450 		cfg[i] |= msb_to_lsb << PACKING_DIR_SHIFT;
451 		cfg[i] |= len << PACKING_LEN_SHIFT;
452 
453 		if (temp_bpw <= BITS_PER_BYTE) {
454 			idx = ((i + 1) * BITS_PER_BYTE) + idx_start;
455 			temp_bpw = bpw;
456 		} else {
457 			idx = idx + idx_delta;
458 			temp_bpw = temp_bpw - BITS_PER_BYTE;
459 		}
460 	}
461 	cfg[iter - 1] |= PACKING_STOP_BIT;
462 	cfg0 = cfg[0] | (cfg[1] << PACKING_VECTOR_SHIFT);
463 	cfg1 = cfg[2] | (cfg[3] << PACKING_VECTOR_SHIFT);
464 
465 	if (tx_cfg) {
466 		writel_relaxed(cfg0, se->base + SE_GENI_TX_PACKING_CFG0);
467 		writel_relaxed(cfg1, se->base + SE_GENI_TX_PACKING_CFG1);
468 	}
469 	if (rx_cfg) {
470 		writel_relaxed(cfg0, se->base + SE_GENI_RX_PACKING_CFG0);
471 		writel_relaxed(cfg1, se->base + SE_GENI_RX_PACKING_CFG1);
472 	}
473 
474 	/*
475 	 * Number of protocol words in each FIFO entry
476 	 * 0 - 4x8, four words in each entry, max word size of 8 bits
477 	 * 1 - 2x16, two words in each entry, max word size of 16 bits
478 	 * 2 - 1x32, one word in each entry, max word size of 32 bits
479 	 * 3 - undefined
480 	 */
481 	if (pack_words || bpw == 32)
482 		writel_relaxed(bpw / 16, se->base + SE_GENI_BYTE_GRAN);
483 }
484 EXPORT_SYMBOL(geni_se_config_packing);
485 
486 static void geni_se_clks_off(struct geni_se *se)
487 {
488 	struct geni_wrapper *wrapper = se->wrapper;
489 
490 	clk_disable_unprepare(se->clk);
491 	clk_bulk_disable_unprepare(wrapper->num_clks, wrapper->clks);
492 }
493 
494 /**
495  * geni_se_resources_off() - Turn off resources associated with the serial
496  *                           engine
497  * @se:	Pointer to the concerned serial engine.
498  *
499  * Return: 0 on success, standard Linux error codes on failure/error.
500  */
501 int geni_se_resources_off(struct geni_se *se)
502 {
503 	int ret;
504 
505 	if (has_acpi_companion(se->dev))
506 		return 0;
507 
508 	ret = pinctrl_pm_select_sleep_state(se->dev);
509 	if (ret)
510 		return ret;
511 
512 	geni_se_clks_off(se);
513 	return 0;
514 }
515 EXPORT_SYMBOL(geni_se_resources_off);
516 
517 static int geni_se_clks_on(struct geni_se *se)
518 {
519 	int ret;
520 	struct geni_wrapper *wrapper = se->wrapper;
521 
522 	ret = clk_bulk_prepare_enable(wrapper->num_clks, wrapper->clks);
523 	if (ret)
524 		return ret;
525 
526 	ret = clk_prepare_enable(se->clk);
527 	if (ret)
528 		clk_bulk_disable_unprepare(wrapper->num_clks, wrapper->clks);
529 	return ret;
530 }
531 
532 /**
533  * geni_se_resources_on() - Turn on resources associated with the serial
534  *                          engine
535  * @se:	Pointer to the concerned serial engine.
536  *
537  * Return: 0 on success, standard Linux error codes on failure/error.
538  */
539 int geni_se_resources_on(struct geni_se *se)
540 {
541 	int ret;
542 
543 	if (has_acpi_companion(se->dev))
544 		return 0;
545 
546 	ret = geni_se_clks_on(se);
547 	if (ret)
548 		return ret;
549 
550 	ret = pinctrl_pm_select_default_state(se->dev);
551 	if (ret)
552 		geni_se_clks_off(se);
553 
554 	return ret;
555 }
556 EXPORT_SYMBOL(geni_se_resources_on);
557 
558 /**
559  * geni_se_clk_tbl_get() - Get the clock table to program DFS
560  * @se:		Pointer to the concerned serial engine.
561  * @tbl:	Table in which the output is returned.
562  *
563  * This function is called by the protocol drivers to determine the different
564  * clock frequencies supported by serial engine core clock. The protocol
565  * drivers use the output to determine the clock frequency index to be
566  * programmed into DFS.
567  *
568  * Return: number of valid performance levels in the table on success,
569  *	   standard Linux error codes on failure.
570  */
571 int geni_se_clk_tbl_get(struct geni_se *se, unsigned long **tbl)
572 {
573 	long freq = 0;
574 	int i;
575 
576 	if (se->clk_perf_tbl) {
577 		*tbl = se->clk_perf_tbl;
578 		return se->num_clk_levels;
579 	}
580 
581 	se->clk_perf_tbl = devm_kcalloc(se->dev, MAX_CLK_PERF_LEVEL,
582 					sizeof(*se->clk_perf_tbl),
583 					GFP_KERNEL);
584 	if (!se->clk_perf_tbl)
585 		return -ENOMEM;
586 
587 	for (i = 0; i < MAX_CLK_PERF_LEVEL; i++) {
588 		freq = clk_round_rate(se->clk, freq + 1);
589 		if (freq <= 0 || freq == se->clk_perf_tbl[i - 1])
590 			break;
591 		se->clk_perf_tbl[i] = freq;
592 	}
593 	se->num_clk_levels = i;
594 	*tbl = se->clk_perf_tbl;
595 	return se->num_clk_levels;
596 }
597 EXPORT_SYMBOL(geni_se_clk_tbl_get);
598 
599 /**
600  * geni_se_clk_freq_match() - Get the matching or closest SE clock frequency
601  * @se:		Pointer to the concerned serial engine.
602  * @req_freq:	Requested clock frequency.
603  * @index:	Index of the resultant frequency in the table.
604  * @res_freq:	Resultant frequency of the source clock.
605  * @exact:	Flag to indicate exact multiple requirement of the requested
606  *		frequency.
607  *
608  * This function is called by the protocol drivers to determine the best match
609  * of the requested frequency as provided by the serial engine clock in order
610  * to meet the performance requirements.
611  *
612  * If we return success:
613  * - if @exact is true  then @res_freq / <an_integer> == @req_freq
614  * - if @exact is false then @res_freq / <an_integer> <= @req_freq
615  *
616  * Return: 0 on success, standard Linux error codes on failure.
617  */
618 int geni_se_clk_freq_match(struct geni_se *se, unsigned long req_freq,
619 			   unsigned int *index, unsigned long *res_freq,
620 			   bool exact)
621 {
622 	unsigned long *tbl;
623 	int num_clk_levels;
624 	int i;
625 	unsigned long best_delta;
626 	unsigned long new_delta;
627 	unsigned int divider;
628 
629 	num_clk_levels = geni_se_clk_tbl_get(se, &tbl);
630 	if (num_clk_levels < 0)
631 		return num_clk_levels;
632 
633 	if (num_clk_levels == 0)
634 		return -EINVAL;
635 
636 	best_delta = ULONG_MAX;
637 	for (i = 0; i < num_clk_levels; i++) {
638 		divider = DIV_ROUND_UP(tbl[i], req_freq);
639 		new_delta = req_freq - tbl[i] / divider;
640 		if (new_delta < best_delta) {
641 			/* We have a new best! */
642 			*index = i;
643 			*res_freq = tbl[i];
644 
645 			/* If the new best is exact then we're done */
646 			if (new_delta == 0)
647 				return 0;
648 
649 			/* Record how close we got */
650 			best_delta = new_delta;
651 		}
652 	}
653 
654 	if (exact)
655 		return -EINVAL;
656 
657 	return 0;
658 }
659 EXPORT_SYMBOL(geni_se_clk_freq_match);
660 
661 #define GENI_SE_DMA_DONE_EN BIT(0)
662 #define GENI_SE_DMA_EOT_EN BIT(1)
663 #define GENI_SE_DMA_AHB_ERR_EN BIT(2)
664 #define GENI_SE_DMA_EOT_BUF BIT(0)
665 /**
666  * geni_se_tx_dma_prep() - Prepare the serial engine for TX DMA transfer
667  * @se:			Pointer to the concerned serial engine.
668  * @buf:		Pointer to the TX buffer.
669  * @len:		Length of the TX buffer.
670  * @iova:		Pointer to store the mapped DMA address.
671  *
672  * This function is used to prepare the buffers for DMA TX.
673  *
674  * Return: 0 on success, standard Linux error codes on failure.
675  */
676 int geni_se_tx_dma_prep(struct geni_se *se, void *buf, size_t len,
677 			dma_addr_t *iova)
678 {
679 	struct geni_wrapper *wrapper = se->wrapper;
680 	u32 val;
681 
682 	if (!wrapper)
683 		return -EINVAL;
684 
685 	*iova = dma_map_single(wrapper->dev, buf, len, DMA_TO_DEVICE);
686 	if (dma_mapping_error(wrapper->dev, *iova))
687 		return -EIO;
688 
689 	val = GENI_SE_DMA_DONE_EN;
690 	val |= GENI_SE_DMA_EOT_EN;
691 	val |= GENI_SE_DMA_AHB_ERR_EN;
692 	writel_relaxed(val, se->base + SE_DMA_TX_IRQ_EN_SET);
693 	writel_relaxed(lower_32_bits(*iova), se->base + SE_DMA_TX_PTR_L);
694 	writel_relaxed(upper_32_bits(*iova), se->base + SE_DMA_TX_PTR_H);
695 	writel_relaxed(GENI_SE_DMA_EOT_BUF, se->base + SE_DMA_TX_ATTR);
696 	writel(len, se->base + SE_DMA_TX_LEN);
697 	return 0;
698 }
699 EXPORT_SYMBOL(geni_se_tx_dma_prep);
700 
701 /**
702  * geni_se_rx_dma_prep() - Prepare the serial engine for RX DMA transfer
703  * @se:			Pointer to the concerned serial engine.
704  * @buf:		Pointer to the RX buffer.
705  * @len:		Length of the RX buffer.
706  * @iova:		Pointer to store the mapped DMA address.
707  *
708  * This function is used to prepare the buffers for DMA RX.
709  *
710  * Return: 0 on success, standard Linux error codes on failure.
711  */
712 int geni_se_rx_dma_prep(struct geni_se *se, void *buf, size_t len,
713 			dma_addr_t *iova)
714 {
715 	struct geni_wrapper *wrapper = se->wrapper;
716 	u32 val;
717 
718 	if (!wrapper)
719 		return -EINVAL;
720 
721 	*iova = dma_map_single(wrapper->dev, buf, len, DMA_FROM_DEVICE);
722 	if (dma_mapping_error(wrapper->dev, *iova))
723 		return -EIO;
724 
725 	val = GENI_SE_DMA_DONE_EN;
726 	val |= GENI_SE_DMA_EOT_EN;
727 	val |= GENI_SE_DMA_AHB_ERR_EN;
728 	writel_relaxed(val, se->base + SE_DMA_RX_IRQ_EN_SET);
729 	writel_relaxed(lower_32_bits(*iova), se->base + SE_DMA_RX_PTR_L);
730 	writel_relaxed(upper_32_bits(*iova), se->base + SE_DMA_RX_PTR_H);
731 	/* RX does not have EOT buffer type bit. So just reset RX_ATTR */
732 	writel_relaxed(0, se->base + SE_DMA_RX_ATTR);
733 	writel(len, se->base + SE_DMA_RX_LEN);
734 	return 0;
735 }
736 EXPORT_SYMBOL(geni_se_rx_dma_prep);
737 
738 /**
739  * geni_se_tx_dma_unprep() - Unprepare the serial engine after TX DMA transfer
740  * @se:			Pointer to the concerned serial engine.
741  * @iova:		DMA address of the TX buffer.
742  * @len:		Length of the TX buffer.
743  *
744  * This function is used to unprepare the DMA buffers after DMA TX.
745  */
746 void geni_se_tx_dma_unprep(struct geni_se *se, dma_addr_t iova, size_t len)
747 {
748 	struct geni_wrapper *wrapper = se->wrapper;
749 
750 	if (!dma_mapping_error(wrapper->dev, iova))
751 		dma_unmap_single(wrapper->dev, iova, len, DMA_TO_DEVICE);
752 }
753 EXPORT_SYMBOL(geni_se_tx_dma_unprep);
754 
755 /**
756  * geni_se_rx_dma_unprep() - Unprepare the serial engine after RX DMA transfer
757  * @se:			Pointer to the concerned serial engine.
758  * @iova:		DMA address of the RX buffer.
759  * @len:		Length of the RX buffer.
760  *
761  * This function is used to unprepare the DMA buffers after DMA RX.
762  */
763 void geni_se_rx_dma_unprep(struct geni_se *se, dma_addr_t iova, size_t len)
764 {
765 	struct geni_wrapper *wrapper = se->wrapper;
766 
767 	if (!dma_mapping_error(wrapper->dev, iova))
768 		dma_unmap_single(wrapper->dev, iova, len, DMA_FROM_DEVICE);
769 }
770 EXPORT_SYMBOL(geni_se_rx_dma_unprep);
771 
772 int geni_icc_get(struct geni_se *se, const char *icc_ddr)
773 {
774 	int i, err;
775 	const char *icc_names[] = {"qup-core", "qup-config", icc_ddr};
776 
777 	if (has_acpi_companion(se->dev))
778 		return 0;
779 
780 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
781 		if (!icc_names[i])
782 			continue;
783 
784 		se->icc_paths[i].path = devm_of_icc_get(se->dev, icc_names[i]);
785 		if (IS_ERR(se->icc_paths[i].path))
786 			goto err;
787 	}
788 
789 	return 0;
790 
791 err:
792 	err = PTR_ERR(se->icc_paths[i].path);
793 	if (err != -EPROBE_DEFER)
794 		dev_err_ratelimited(se->dev, "Failed to get ICC path '%s': %d\n",
795 					icc_names[i], err);
796 	return err;
797 
798 }
799 EXPORT_SYMBOL(geni_icc_get);
800 
801 int geni_icc_set_bw(struct geni_se *se)
802 {
803 	int i, ret;
804 
805 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
806 		ret = icc_set_bw(se->icc_paths[i].path,
807 			se->icc_paths[i].avg_bw, se->icc_paths[i].avg_bw);
808 		if (ret) {
809 			dev_err_ratelimited(se->dev, "ICC BW voting failed on path '%s': %d\n",
810 					icc_path_names[i], ret);
811 			return ret;
812 		}
813 	}
814 
815 	return 0;
816 }
817 EXPORT_SYMBOL(geni_icc_set_bw);
818 
819 void geni_icc_set_tag(struct geni_se *se, u32 tag)
820 {
821 	int i;
822 
823 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++)
824 		icc_set_tag(se->icc_paths[i].path, tag);
825 }
826 EXPORT_SYMBOL(geni_icc_set_tag);
827 
828 /* To do: Replace this by icc_bulk_enable once it's implemented in ICC core */
829 int geni_icc_enable(struct geni_se *se)
830 {
831 	int i, ret;
832 
833 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
834 		ret = icc_enable(se->icc_paths[i].path);
835 		if (ret) {
836 			dev_err_ratelimited(se->dev, "ICC enable failed on path '%s': %d\n",
837 					icc_path_names[i], ret);
838 			return ret;
839 		}
840 	}
841 
842 	return 0;
843 }
844 EXPORT_SYMBOL(geni_icc_enable);
845 
846 int geni_icc_disable(struct geni_se *se)
847 {
848 	int i, ret;
849 
850 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
851 		ret = icc_disable(se->icc_paths[i].path);
852 		if (ret) {
853 			dev_err_ratelimited(se->dev, "ICC disable failed on path '%s': %d\n",
854 					icc_path_names[i], ret);
855 			return ret;
856 		}
857 	}
858 
859 	return 0;
860 }
861 EXPORT_SYMBOL(geni_icc_disable);
862 
863 static int geni_se_probe(struct platform_device *pdev)
864 {
865 	struct device *dev = &pdev->dev;
866 	struct geni_wrapper *wrapper;
867 	int ret;
868 
869 	wrapper = devm_kzalloc(dev, sizeof(*wrapper), GFP_KERNEL);
870 	if (!wrapper)
871 		return -ENOMEM;
872 
873 	wrapper->dev = dev;
874 	wrapper->base = devm_platform_ioremap_resource(pdev, 0);
875 	if (IS_ERR(wrapper->base))
876 		return PTR_ERR(wrapper->base);
877 
878 	if (!has_acpi_companion(&pdev->dev)) {
879 		const struct geni_se_desc *desc;
880 		int i;
881 
882 		desc = device_get_match_data(&pdev->dev);
883 		if (!desc)
884 			return -EINVAL;
885 
886 		wrapper->num_clks = min_t(unsigned int, desc->num_clks, MAX_CLKS);
887 
888 		for (i = 0; i < wrapper->num_clks; ++i)
889 			wrapper->clks[i].id = desc->clks[i];
890 
891 		ret = of_count_phandle_with_args(dev->of_node, "clocks", "#clock-cells");
892 		if (ret < 0) {
893 			dev_err(dev, "invalid clocks property at %pOF\n", dev->of_node);
894 			return ret;
895 		}
896 
897 		if (ret < wrapper->num_clks) {
898 			dev_err(dev, "invalid clocks count at %pOF, expected %d entries\n",
899 				dev->of_node, wrapper->num_clks);
900 			return -EINVAL;
901 		}
902 
903 		ret = devm_clk_bulk_get(dev, wrapper->num_clks, wrapper->clks);
904 		if (ret) {
905 			dev_err(dev, "Err getting clks %d\n", ret);
906 			return ret;
907 		}
908 	}
909 
910 	dev_set_drvdata(dev, wrapper);
911 	dev_dbg(dev, "GENI SE Driver probed\n");
912 	return devm_of_platform_populate(dev);
913 }
914 
915 static const char * const qup_clks[] = {
916 	"m-ahb",
917 	"s-ahb",
918 };
919 
920 static const struct geni_se_desc qup_desc = {
921 	.clks = qup_clks,
922 	.num_clks = ARRAY_SIZE(qup_clks),
923 };
924 
925 static const char * const i2c_master_hub_clks[] = {
926 	"s-ahb",
927 };
928 
929 static const struct geni_se_desc i2c_master_hub_desc = {
930 	.clks = i2c_master_hub_clks,
931 	.num_clks = ARRAY_SIZE(i2c_master_hub_clks),
932 };
933 
934 static const struct of_device_id geni_se_dt_match[] = {
935 	{ .compatible = "qcom,geni-se-qup", .data = &qup_desc },
936 	{ .compatible = "qcom,geni-se-i2c-master-hub", .data = &i2c_master_hub_desc },
937 	{}
938 };
939 MODULE_DEVICE_TABLE(of, geni_se_dt_match);
940 
941 static struct platform_driver geni_se_driver = {
942 	.driver = {
943 		.name = "geni_se_qup",
944 		.of_match_table = geni_se_dt_match,
945 	},
946 	.probe = geni_se_probe,
947 };
948 module_platform_driver(geni_se_driver);
949 
950 MODULE_DESCRIPTION("GENI Serial Engine Driver");
951 MODULE_LICENSE("GPL v2");
952