xref: /openbmc/linux/drivers/mmc/host/cavium-octeon.c (revision 82e6fdd6)
1 /*
2  * Driver for MMC and SSD cards for Cavium OCTEON SOCs.
3  *
4  * This file is subject to the terms and conditions of the GNU General Public
5  * License.  See the file "COPYING" in the main directory of this archive
6  * for more details.
7  *
8  * Copyright (C) 2012-2017 Cavium Inc.
9  */
10 #include <linux/dma-mapping.h>
11 #include <linux/gpio/consumer.h>
12 #include <linux/interrupt.h>
13 #include <linux/mmc/mmc.h>
14 #include <linux/mmc/slot-gpio.h>
15 #include <linux/module.h>
16 #include <linux/of_platform.h>
17 #include <asm/octeon/octeon.h>
18 #include "cavium.h"
19 
20 #define CVMX_MIO_BOOT_CTL CVMX_ADD_IO_SEG(0x00011800000000D0ull)
21 
22 /*
23  * The l2c* functions below are used for the EMMC-17978 workaround.
24  *
25  * Due to a bug in the design of the MMC bus hardware, the 2nd to last
26  * cache block of a DMA read must be locked into the L2 Cache.
27  * Otherwise, data corruption may occur.
28  */
29 static inline void *phys_to_ptr(u64 address)
30 {
31 	return (void *)(address | (1ull << 63)); /* XKPHYS */
32 }
33 
34 /*
35  * Lock a single line into L2. The line is zeroed before locking
36  * to make sure no dram accesses are made.
37  */
38 static void l2c_lock_line(u64 addr)
39 {
40 	char *addr_ptr = phys_to_ptr(addr);
41 
42 	asm volatile (
43 		"cache 31, %[line]"	/* Unlock the line */
44 		::[line] "m" (*addr_ptr));
45 }
46 
47 /* Unlock a single line in the L2 cache. */
48 static void l2c_unlock_line(u64 addr)
49 {
50 	char *addr_ptr = phys_to_ptr(addr);
51 
52 	asm volatile (
53 		"cache 23, %[line]"	/* Unlock the line */
54 		::[line] "m" (*addr_ptr));
55 }
56 
57 /* Locks a memory region in the L2 cache. */
58 static void l2c_lock_mem_region(u64 start, u64 len)
59 {
60 	u64 end;
61 
62 	/* Round start/end to cache line boundaries */
63 	end = ALIGN(start + len - 1, CVMX_CACHE_LINE_SIZE);
64 	start = ALIGN(start, CVMX_CACHE_LINE_SIZE);
65 
66 	while (start <= end) {
67 		l2c_lock_line(start);
68 		start += CVMX_CACHE_LINE_SIZE;
69 	}
70 	asm volatile("sync");
71 }
72 
73 /* Unlock a memory region in the L2 cache. */
74 static void l2c_unlock_mem_region(u64 start, u64 len)
75 {
76 	u64 end;
77 
78 	/* Round start/end to cache line boundaries */
79 	end = ALIGN(start + len - 1, CVMX_CACHE_LINE_SIZE);
80 	start = ALIGN(start, CVMX_CACHE_LINE_SIZE);
81 
82 	while (start <= end) {
83 		l2c_unlock_line(start);
84 		start += CVMX_CACHE_LINE_SIZE;
85 	}
86 }
87 
88 static void octeon_mmc_acquire_bus(struct cvm_mmc_host *host)
89 {
90 	if (!host->has_ciu3) {
91 		down(&octeon_bootbus_sem);
92 		/* For CN70XX, switch the MMC controller onto the bus. */
93 		if (OCTEON_IS_MODEL(OCTEON_CN70XX))
94 			writeq(0, (void __iomem *)CVMX_MIO_BOOT_CTL);
95 	} else {
96 		down(&host->mmc_serializer);
97 	}
98 }
99 
100 static void octeon_mmc_release_bus(struct cvm_mmc_host *host)
101 {
102 	if (!host->has_ciu3)
103 		up(&octeon_bootbus_sem);
104 	else
105 		up(&host->mmc_serializer);
106 }
107 
108 static void octeon_mmc_int_enable(struct cvm_mmc_host *host, u64 val)
109 {
110 	writeq(val, host->base + MIO_EMM_INT(host));
111 	if (!host->has_ciu3)
112 		writeq(val, host->base + MIO_EMM_INT_EN(host));
113 }
114 
115 static void octeon_mmc_set_shared_power(struct cvm_mmc_host *host, int dir)
116 {
117 	if (dir == 0)
118 		if (!atomic_dec_return(&host->shared_power_users))
119 			gpiod_set_value_cansleep(host->global_pwr_gpiod, 0);
120 	if (dir == 1)
121 		if (atomic_inc_return(&host->shared_power_users) == 1)
122 			gpiod_set_value_cansleep(host->global_pwr_gpiod, 1);
123 }
124 
125 static void octeon_mmc_dmar_fixup(struct cvm_mmc_host *host,
126 				  struct mmc_command *cmd,
127 				  struct mmc_data *data,
128 				  u64 addr)
129 {
130 	if (cmd->opcode != MMC_WRITE_MULTIPLE_BLOCK)
131 		return;
132 	if (data->blksz * data->blocks <= 1024)
133 		return;
134 
135 	host->n_minus_one = addr + (data->blksz * data->blocks) - 1024;
136 	l2c_lock_mem_region(host->n_minus_one, 512);
137 }
138 
139 static void octeon_mmc_dmar_fixup_done(struct cvm_mmc_host *host)
140 {
141 	if (!host->n_minus_one)
142 		return;
143 	l2c_unlock_mem_region(host->n_minus_one, 512);
144 	host->n_minus_one = 0;
145 }
146 
147 static int octeon_mmc_probe(struct platform_device *pdev)
148 {
149 	struct device_node *cn, *node = pdev->dev.of_node;
150 	struct cvm_mmc_host *host;
151 	struct resource	*res;
152 	void __iomem *base;
153 	int mmc_irq[9];
154 	int i, ret = 0;
155 	u64 val;
156 
157 	host = devm_kzalloc(&pdev->dev, sizeof(*host), GFP_KERNEL);
158 	if (!host)
159 		return -ENOMEM;
160 
161 	spin_lock_init(&host->irq_handler_lock);
162 	sema_init(&host->mmc_serializer, 1);
163 
164 	host->dev = &pdev->dev;
165 	host->acquire_bus = octeon_mmc_acquire_bus;
166 	host->release_bus = octeon_mmc_release_bus;
167 	host->int_enable = octeon_mmc_int_enable;
168 	host->set_shared_power = octeon_mmc_set_shared_power;
169 	if (OCTEON_IS_MODEL(OCTEON_CN6XXX) ||
170 	    OCTEON_IS_MODEL(OCTEON_CNF7XXX)) {
171 		host->dmar_fixup = octeon_mmc_dmar_fixup;
172 		host->dmar_fixup_done = octeon_mmc_dmar_fixup_done;
173 	}
174 
175 	host->sys_freq = octeon_get_io_clock_rate();
176 
177 	if (of_device_is_compatible(node, "cavium,octeon-7890-mmc")) {
178 		host->big_dma_addr = true;
179 		host->need_irq_handler_lock = true;
180 		host->has_ciu3 = true;
181 		host->use_sg = true;
182 		/*
183 		 * First seven are the EMM_INT bits 0..6, then two for
184 		 * the EMM_DMA_INT bits
185 		 */
186 		for (i = 0; i < 9; i++) {
187 			mmc_irq[i] = platform_get_irq(pdev, i);
188 			if (mmc_irq[i] < 0)
189 				return mmc_irq[i];
190 
191 			/* work around legacy u-boot device trees */
192 			irq_set_irq_type(mmc_irq[i], IRQ_TYPE_EDGE_RISING);
193 		}
194 	} else {
195 		host->big_dma_addr = false;
196 		host->need_irq_handler_lock = false;
197 		host->has_ciu3 = false;
198 		/* First one is EMM second DMA */
199 		for (i = 0; i < 2; i++) {
200 			mmc_irq[i] = platform_get_irq(pdev, i);
201 			if (mmc_irq[i] < 0)
202 				return mmc_irq[i];
203 		}
204 	}
205 
206 	host->last_slot = -1;
207 
208 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
209 	if (!res) {
210 		dev_err(&pdev->dev, "Platform resource[0] is missing\n");
211 		return -ENXIO;
212 	}
213 	base = devm_ioremap_resource(&pdev->dev, res);
214 	if (IS_ERR(base))
215 		return PTR_ERR(base);
216 	host->base = (void __iomem *)base;
217 	host->reg_off = 0;
218 
219 	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
220 	if (!res) {
221 		dev_err(&pdev->dev, "Platform resource[1] is missing\n");
222 		return -EINVAL;
223 	}
224 	base = devm_ioremap_resource(&pdev->dev, res);
225 	if (IS_ERR(base))
226 		return PTR_ERR(base);
227 	host->dma_base = (void __iomem *)base;
228 	/*
229 	 * To keep the register addresses shared we intentionaly use
230 	 * a negative offset here, first register used on Octeon therefore
231 	 * starts at 0x20 (MIO_EMM_DMA_CFG).
232 	 */
233 	host->reg_off_dma = -0x20;
234 
235 	ret = dma_set_mask(&pdev->dev, DMA_BIT_MASK(64));
236 	if (ret)
237 		return ret;
238 
239 	/*
240 	 * Clear out any pending interrupts that may be left over from
241 	 * bootloader.
242 	 */
243 	val = readq(host->base + MIO_EMM_INT(host));
244 	writeq(val, host->base + MIO_EMM_INT(host));
245 
246 	if (host->has_ciu3) {
247 		/* Only CMD_DONE, DMA_DONE, CMD_ERR, DMA_ERR */
248 		for (i = 1; i <= 4; i++) {
249 			ret = devm_request_irq(&pdev->dev, mmc_irq[i],
250 					       cvm_mmc_interrupt,
251 					       0, cvm_mmc_irq_names[i], host);
252 			if (ret < 0) {
253 				dev_err(&pdev->dev, "Error: devm_request_irq %d\n",
254 					mmc_irq[i]);
255 				return ret;
256 			}
257 		}
258 	} else {
259 		ret = devm_request_irq(&pdev->dev, mmc_irq[0],
260 				       cvm_mmc_interrupt, 0, KBUILD_MODNAME,
261 				       host);
262 		if (ret < 0) {
263 			dev_err(&pdev->dev, "Error: devm_request_irq %d\n",
264 				mmc_irq[0]);
265 			return ret;
266 		}
267 	}
268 
269 	host->global_pwr_gpiod = devm_gpiod_get_optional(&pdev->dev,
270 							 "power",
271 							 GPIOD_OUT_HIGH);
272 	if (IS_ERR(host->global_pwr_gpiod)) {
273 		dev_err(&pdev->dev, "Invalid power GPIO\n");
274 		return PTR_ERR(host->global_pwr_gpiod);
275 	}
276 
277 	platform_set_drvdata(pdev, host);
278 
279 	i = 0;
280 	for_each_child_of_node(node, cn) {
281 		host->slot_pdev[i] =
282 			of_platform_device_create(cn, NULL, &pdev->dev);
283 		if (!host->slot_pdev[i]) {
284 			i++;
285 			continue;
286 		}
287 		ret = cvm_mmc_of_slot_probe(&host->slot_pdev[i]->dev, host);
288 		if (ret) {
289 			dev_err(&pdev->dev, "Error populating slots\n");
290 			octeon_mmc_set_shared_power(host, 0);
291 			goto error;
292 		}
293 		i++;
294 	}
295 	return 0;
296 
297 error:
298 	for (i = 0; i < CAVIUM_MAX_MMC; i++) {
299 		if (host->slot[i])
300 			cvm_mmc_of_slot_remove(host->slot[i]);
301 		if (host->slot_pdev[i])
302 			of_platform_device_destroy(&host->slot_pdev[i]->dev, NULL);
303 	}
304 	return ret;
305 }
306 
307 static int octeon_mmc_remove(struct platform_device *pdev)
308 {
309 	struct cvm_mmc_host *host = platform_get_drvdata(pdev);
310 	u64 dma_cfg;
311 	int i;
312 
313 	for (i = 0; i < CAVIUM_MAX_MMC; i++)
314 		if (host->slot[i])
315 			cvm_mmc_of_slot_remove(host->slot[i]);
316 
317 	dma_cfg = readq(host->dma_base + MIO_EMM_DMA_CFG(host));
318 	dma_cfg &= ~MIO_EMM_DMA_CFG_EN;
319 	writeq(dma_cfg, host->dma_base + MIO_EMM_DMA_CFG(host));
320 
321 	octeon_mmc_set_shared_power(host, 0);
322 	return 0;
323 }
324 
325 static const struct of_device_id octeon_mmc_match[] = {
326 	{
327 		.compatible = "cavium,octeon-6130-mmc",
328 	},
329 	{
330 		.compatible = "cavium,octeon-7890-mmc",
331 	},
332 	{},
333 };
334 MODULE_DEVICE_TABLE(of, octeon_mmc_match);
335 
336 static struct platform_driver octeon_mmc_driver = {
337 	.probe		= octeon_mmc_probe,
338 	.remove		= octeon_mmc_remove,
339 	.driver		= {
340 		.name	= KBUILD_MODNAME,
341 		.of_match_table = octeon_mmc_match,
342 	},
343 };
344 
345 module_platform_driver(octeon_mmc_driver);
346 
347 MODULE_AUTHOR("Cavium Inc. <support@cavium.com>");
348 MODULE_DESCRIPTION("Low-level driver for Cavium OCTEON MMC/SSD card");
349 MODULE_LICENSE("GPL");
350