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