xref: /openbmc/linux/drivers/soc/qcom/qcom-geni-se.c (revision ecc23d0a422a3118fcf6e4f0a46e17a6c2047b02)
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  */
geni_se_get_qup_hw_version(struct geni_se * se)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 
geni_se_io_set_mode(void __iomem * base)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 
geni_se_io_init(void __iomem * base)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 
geni_se_irq_clear(struct geni_se * se)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  */
geni_se_init(struct geni_se * se,u32 rx_wm,u32 rx_rfr)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 
geni_se_select_fifo_mode(struct geni_se * se)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 
geni_se_select_dma_mode(struct geni_se * se)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 
geni_se_select_gpi_mode(struct geni_se * se)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  */
geni_se_select_mode(struct geni_se * se,enum geni_se_xfer_mode mode)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  */
geni_se_config_packing(struct geni_se * se,int bpw,int pack_words,bool msb_to_lsb,bool tx_cfg,bool rx_cfg)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 
geni_se_clks_off(struct geni_se * se)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  */
geni_se_resources_off(struct geni_se * se)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 
geni_se_clks_on(struct geni_se * se)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  */
geni_se_resources_on(struct geni_se * se)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  */
geni_se_clk_tbl_get(struct geni_se * se,unsigned long ** tbl)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 ||
590 		    (i > 0 && freq == se->clk_perf_tbl[i - 1]))
591 			break;
592 		se->clk_perf_tbl[i] = freq;
593 	}
594 	se->num_clk_levels = i;
595 	*tbl = se->clk_perf_tbl;
596 	return se->num_clk_levels;
597 }
598 EXPORT_SYMBOL(geni_se_clk_tbl_get);
599 
600 /**
601  * geni_se_clk_freq_match() - Get the matching or closest SE clock frequency
602  * @se:		Pointer to the concerned serial engine.
603  * @req_freq:	Requested clock frequency.
604  * @index:	Index of the resultant frequency in the table.
605  * @res_freq:	Resultant frequency of the source clock.
606  * @exact:	Flag to indicate exact multiple requirement of the requested
607  *		frequency.
608  *
609  * This function is called by the protocol drivers to determine the best match
610  * of the requested frequency as provided by the serial engine clock in order
611  * to meet the performance requirements.
612  *
613  * If we return success:
614  * - if @exact is true  then @res_freq / <an_integer> == @req_freq
615  * - if @exact is false then @res_freq / <an_integer> <= @req_freq
616  *
617  * Return: 0 on success, standard Linux error codes on failure.
618  */
geni_se_clk_freq_match(struct geni_se * se,unsigned long req_freq,unsigned int * index,unsigned long * res_freq,bool exact)619 int geni_se_clk_freq_match(struct geni_se *se, unsigned long req_freq,
620 			   unsigned int *index, unsigned long *res_freq,
621 			   bool exact)
622 {
623 	unsigned long *tbl;
624 	int num_clk_levels;
625 	int i;
626 	unsigned long best_delta;
627 	unsigned long new_delta;
628 	unsigned int divider;
629 
630 	num_clk_levels = geni_se_clk_tbl_get(se, &tbl);
631 	if (num_clk_levels < 0)
632 		return num_clk_levels;
633 
634 	if (num_clk_levels == 0)
635 		return -EINVAL;
636 
637 	best_delta = ULONG_MAX;
638 	for (i = 0; i < num_clk_levels; i++) {
639 		divider = DIV_ROUND_UP(tbl[i], req_freq);
640 		new_delta = req_freq - tbl[i] / divider;
641 		if (new_delta < best_delta) {
642 			/* We have a new best! */
643 			*index = i;
644 			*res_freq = tbl[i];
645 
646 			/* If the new best is exact then we're done */
647 			if (new_delta == 0)
648 				return 0;
649 
650 			/* Record how close we got */
651 			best_delta = new_delta;
652 		}
653 	}
654 
655 	if (exact)
656 		return -EINVAL;
657 
658 	return 0;
659 }
660 EXPORT_SYMBOL(geni_se_clk_freq_match);
661 
662 #define GENI_SE_DMA_DONE_EN BIT(0)
663 #define GENI_SE_DMA_EOT_EN BIT(1)
664 #define GENI_SE_DMA_AHB_ERR_EN BIT(2)
665 #define GENI_SE_DMA_EOT_BUF BIT(0)
666 
667 /**
668  * geni_se_tx_init_dma() - Initiate TX DMA transfer on the serial engine
669  * @se:			Pointer to the concerned serial engine.
670  * @iova:		Mapped DMA address.
671  * @len:		Length of the TX buffer.
672  *
673  * This function is used to initiate DMA TX transfer.
674  */
geni_se_tx_init_dma(struct geni_se * se,dma_addr_t iova,size_t len)675 void geni_se_tx_init_dma(struct geni_se *se, dma_addr_t iova, size_t len)
676 {
677 	u32 val;
678 
679 	val = GENI_SE_DMA_DONE_EN;
680 	val |= GENI_SE_DMA_EOT_EN;
681 	val |= GENI_SE_DMA_AHB_ERR_EN;
682 	writel_relaxed(val, se->base + SE_DMA_TX_IRQ_EN_SET);
683 	writel_relaxed(lower_32_bits(iova), se->base + SE_DMA_TX_PTR_L);
684 	writel_relaxed(upper_32_bits(iova), se->base + SE_DMA_TX_PTR_H);
685 	writel_relaxed(GENI_SE_DMA_EOT_BUF, se->base + SE_DMA_TX_ATTR);
686 	writel(len, se->base + SE_DMA_TX_LEN);
687 }
688 EXPORT_SYMBOL(geni_se_tx_init_dma);
689 
690 /**
691  * geni_se_tx_dma_prep() - Prepare the serial engine for TX DMA transfer
692  * @se:			Pointer to the concerned serial engine.
693  * @buf:		Pointer to the TX buffer.
694  * @len:		Length of the TX buffer.
695  * @iova:		Pointer to store the mapped DMA address.
696  *
697  * This function is used to prepare the buffers for DMA TX.
698  *
699  * Return: 0 on success, standard Linux error codes on failure.
700  */
geni_se_tx_dma_prep(struct geni_se * se,void * buf,size_t len,dma_addr_t * iova)701 int geni_se_tx_dma_prep(struct geni_se *se, void *buf, size_t len,
702 			dma_addr_t *iova)
703 {
704 	struct geni_wrapper *wrapper = se->wrapper;
705 
706 	if (!wrapper)
707 		return -EINVAL;
708 
709 	*iova = dma_map_single(wrapper->dev, buf, len, DMA_TO_DEVICE);
710 	if (dma_mapping_error(wrapper->dev, *iova))
711 		return -EIO;
712 
713 	geni_se_tx_init_dma(se, *iova, len);
714 	return 0;
715 }
716 EXPORT_SYMBOL(geni_se_tx_dma_prep);
717 
718 /**
719  * geni_se_rx_init_dma() - Initiate RX DMA transfer on the serial engine
720  * @se:			Pointer to the concerned serial engine.
721  * @iova:		Mapped DMA address.
722  * @len:		Length of the RX buffer.
723  *
724  * This function is used to initiate DMA RX transfer.
725  */
geni_se_rx_init_dma(struct geni_se * se,dma_addr_t iova,size_t len)726 void geni_se_rx_init_dma(struct geni_se *se, dma_addr_t iova, size_t len)
727 {
728 	u32 val;
729 
730 	val = GENI_SE_DMA_DONE_EN;
731 	val |= GENI_SE_DMA_EOT_EN;
732 	val |= GENI_SE_DMA_AHB_ERR_EN;
733 	writel_relaxed(val, se->base + SE_DMA_RX_IRQ_EN_SET);
734 	writel_relaxed(lower_32_bits(iova), se->base + SE_DMA_RX_PTR_L);
735 	writel_relaxed(upper_32_bits(iova), se->base + SE_DMA_RX_PTR_H);
736 	/* RX does not have EOT buffer type bit. So just reset RX_ATTR */
737 	writel_relaxed(0, se->base + SE_DMA_RX_ATTR);
738 	writel(len, se->base + SE_DMA_RX_LEN);
739 }
740 EXPORT_SYMBOL(geni_se_rx_init_dma);
741 
742 /**
743  * geni_se_rx_dma_prep() - Prepare the serial engine for RX DMA transfer
744  * @se:			Pointer to the concerned serial engine.
745  * @buf:		Pointer to the RX buffer.
746  * @len:		Length of the RX buffer.
747  * @iova:		Pointer to store the mapped DMA address.
748  *
749  * This function is used to prepare the buffers for DMA RX.
750  *
751  * Return: 0 on success, standard Linux error codes on failure.
752  */
geni_se_rx_dma_prep(struct geni_se * se,void * buf,size_t len,dma_addr_t * iova)753 int geni_se_rx_dma_prep(struct geni_se *se, void *buf, size_t len,
754 			dma_addr_t *iova)
755 {
756 	struct geni_wrapper *wrapper = se->wrapper;
757 
758 	if (!wrapper)
759 		return -EINVAL;
760 
761 	*iova = dma_map_single(wrapper->dev, buf, len, DMA_FROM_DEVICE);
762 	if (dma_mapping_error(wrapper->dev, *iova))
763 		return -EIO;
764 
765 	geni_se_rx_init_dma(se, *iova, len);
766 	return 0;
767 }
768 EXPORT_SYMBOL(geni_se_rx_dma_prep);
769 
770 /**
771  * geni_se_tx_dma_unprep() - Unprepare the serial engine after TX DMA transfer
772  * @se:			Pointer to the concerned serial engine.
773  * @iova:		DMA address of the TX buffer.
774  * @len:		Length of the TX buffer.
775  *
776  * This function is used to unprepare the DMA buffers after DMA TX.
777  */
geni_se_tx_dma_unprep(struct geni_se * se,dma_addr_t iova,size_t len)778 void geni_se_tx_dma_unprep(struct geni_se *se, dma_addr_t iova, size_t len)
779 {
780 	struct geni_wrapper *wrapper = se->wrapper;
781 
782 	if (!dma_mapping_error(wrapper->dev, iova))
783 		dma_unmap_single(wrapper->dev, iova, len, DMA_TO_DEVICE);
784 }
785 EXPORT_SYMBOL(geni_se_tx_dma_unprep);
786 
787 /**
788  * geni_se_rx_dma_unprep() - Unprepare the serial engine after RX DMA transfer
789  * @se:			Pointer to the concerned serial engine.
790  * @iova:		DMA address of the RX buffer.
791  * @len:		Length of the RX buffer.
792  *
793  * This function is used to unprepare the DMA buffers after DMA RX.
794  */
geni_se_rx_dma_unprep(struct geni_se * se,dma_addr_t iova,size_t len)795 void geni_se_rx_dma_unprep(struct geni_se *se, dma_addr_t iova, size_t len)
796 {
797 	struct geni_wrapper *wrapper = se->wrapper;
798 
799 	if (!dma_mapping_error(wrapper->dev, iova))
800 		dma_unmap_single(wrapper->dev, iova, len, DMA_FROM_DEVICE);
801 }
802 EXPORT_SYMBOL(geni_se_rx_dma_unprep);
803 
geni_icc_get(struct geni_se * se,const char * icc_ddr)804 int geni_icc_get(struct geni_se *se, const char *icc_ddr)
805 {
806 	int i, err;
807 	const char *icc_names[] = {"qup-core", "qup-config", icc_ddr};
808 
809 	if (has_acpi_companion(se->dev))
810 		return 0;
811 
812 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
813 		if (!icc_names[i])
814 			continue;
815 
816 		se->icc_paths[i].path = devm_of_icc_get(se->dev, icc_names[i]);
817 		if (IS_ERR(se->icc_paths[i].path))
818 			goto err;
819 	}
820 
821 	return 0;
822 
823 err:
824 	err = PTR_ERR(se->icc_paths[i].path);
825 	if (err != -EPROBE_DEFER)
826 		dev_err_ratelimited(se->dev, "Failed to get ICC path '%s': %d\n",
827 					icc_names[i], err);
828 	return err;
829 
830 }
831 EXPORT_SYMBOL(geni_icc_get);
832 
geni_icc_set_bw(struct geni_se * se)833 int geni_icc_set_bw(struct geni_se *se)
834 {
835 	int i, ret;
836 
837 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
838 		ret = icc_set_bw(se->icc_paths[i].path,
839 			se->icc_paths[i].avg_bw, se->icc_paths[i].avg_bw);
840 		if (ret) {
841 			dev_err_ratelimited(se->dev, "ICC BW voting failed on path '%s': %d\n",
842 					icc_path_names[i], ret);
843 			return ret;
844 		}
845 	}
846 
847 	return 0;
848 }
849 EXPORT_SYMBOL(geni_icc_set_bw);
850 
geni_icc_set_tag(struct geni_se * se,u32 tag)851 void geni_icc_set_tag(struct geni_se *se, u32 tag)
852 {
853 	int i;
854 
855 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++)
856 		icc_set_tag(se->icc_paths[i].path, tag);
857 }
858 EXPORT_SYMBOL(geni_icc_set_tag);
859 
860 /* To do: Replace this by icc_bulk_enable once it's implemented in ICC core */
geni_icc_enable(struct geni_se * se)861 int geni_icc_enable(struct geni_se *se)
862 {
863 	int i, ret;
864 
865 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
866 		ret = icc_enable(se->icc_paths[i].path);
867 		if (ret) {
868 			dev_err_ratelimited(se->dev, "ICC enable failed on path '%s': %d\n",
869 					icc_path_names[i], ret);
870 			return ret;
871 		}
872 	}
873 
874 	return 0;
875 }
876 EXPORT_SYMBOL(geni_icc_enable);
877 
geni_icc_disable(struct geni_se * se)878 int geni_icc_disable(struct geni_se *se)
879 {
880 	int i, ret;
881 
882 	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
883 		ret = icc_disable(se->icc_paths[i].path);
884 		if (ret) {
885 			dev_err_ratelimited(se->dev, "ICC disable failed on path '%s': %d\n",
886 					icc_path_names[i], ret);
887 			return ret;
888 		}
889 	}
890 
891 	return 0;
892 }
893 EXPORT_SYMBOL(geni_icc_disable);
894 
geni_se_probe(struct platform_device * pdev)895 static int geni_se_probe(struct platform_device *pdev)
896 {
897 	struct device *dev = &pdev->dev;
898 	struct geni_wrapper *wrapper;
899 	int ret;
900 
901 	wrapper = devm_kzalloc(dev, sizeof(*wrapper), GFP_KERNEL);
902 	if (!wrapper)
903 		return -ENOMEM;
904 
905 	wrapper->dev = dev;
906 	wrapper->base = devm_platform_ioremap_resource(pdev, 0);
907 	if (IS_ERR(wrapper->base))
908 		return PTR_ERR(wrapper->base);
909 
910 	if (!has_acpi_companion(&pdev->dev)) {
911 		const struct geni_se_desc *desc;
912 		int i;
913 
914 		desc = device_get_match_data(&pdev->dev);
915 		if (!desc)
916 			return -EINVAL;
917 
918 		wrapper->num_clks = min_t(unsigned int, desc->num_clks, MAX_CLKS);
919 
920 		for (i = 0; i < wrapper->num_clks; ++i)
921 			wrapper->clks[i].id = desc->clks[i];
922 
923 		ret = of_count_phandle_with_args(dev->of_node, "clocks", "#clock-cells");
924 		if (ret < 0) {
925 			dev_err(dev, "invalid clocks property at %pOF\n", dev->of_node);
926 			return ret;
927 		}
928 
929 		if (ret < wrapper->num_clks) {
930 			dev_err(dev, "invalid clocks count at %pOF, expected %d entries\n",
931 				dev->of_node, wrapper->num_clks);
932 			return -EINVAL;
933 		}
934 
935 		ret = devm_clk_bulk_get(dev, wrapper->num_clks, wrapper->clks);
936 		if (ret) {
937 			dev_err(dev, "Err getting clks %d\n", ret);
938 			return ret;
939 		}
940 	}
941 
942 	dev_set_drvdata(dev, wrapper);
943 	dev_dbg(dev, "GENI SE Driver probed\n");
944 	return devm_of_platform_populate(dev);
945 }
946 
947 static const char * const qup_clks[] = {
948 	"m-ahb",
949 	"s-ahb",
950 };
951 
952 static const struct geni_se_desc qup_desc = {
953 	.clks = qup_clks,
954 	.num_clks = ARRAY_SIZE(qup_clks),
955 };
956 
957 static const char * const i2c_master_hub_clks[] = {
958 	"s-ahb",
959 };
960 
961 static const struct geni_se_desc i2c_master_hub_desc = {
962 	.clks = i2c_master_hub_clks,
963 	.num_clks = ARRAY_SIZE(i2c_master_hub_clks),
964 };
965 
966 static const struct of_device_id geni_se_dt_match[] = {
967 	{ .compatible = "qcom,geni-se-qup", .data = &qup_desc },
968 	{ .compatible = "qcom,geni-se-i2c-master-hub", .data = &i2c_master_hub_desc },
969 	{}
970 };
971 MODULE_DEVICE_TABLE(of, geni_se_dt_match);
972 
973 static struct platform_driver geni_se_driver = {
974 	.driver = {
975 		.name = "geni_se_qup",
976 		.of_match_table = geni_se_dt_match,
977 	},
978 	.probe = geni_se_probe,
979 };
980 module_platform_driver(geni_se_driver);
981 
982 MODULE_DESCRIPTION("GENI Serial Engine Driver");
983 MODULE_LICENSE("GPL v2");
984