xref: /openbmc/linux/drivers/ata/ahci_xgene.c (revision e0bf6c5c)
1 /*
2  * AppliedMicro X-Gene SoC SATA Host Controller Driver
3  *
4  * Copyright (c) 2014, Applied Micro Circuits Corporation
5  * Author: Loc Ho <lho@apm.com>
6  *         Tuan Phan <tphan@apm.com>
7  *         Suman Tripathi <stripathi@apm.com>
8  *
9  * This program is free software; you can redistribute  it and/or modify it
10  * under  the terms of  the GNU General  Public License as published by the
11  * Free Software Foundation;  either version 2 of the  License, or (at your
12  * option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
21  *
22  * NOTE: PM support is not currently available.
23  *
24  */
25 #include <linux/module.h>
26 #include <linux/platform_device.h>
27 #include <linux/ahci_platform.h>
28 #include <linux/of_address.h>
29 #include <linux/of_irq.h>
30 #include <linux/phy/phy.h>
31 #include "ahci.h"
32 
33 #define DRV_NAME "xgene-ahci"
34 
35 /* Max # of disk per a controller */
36 #define MAX_AHCI_CHN_PERCTR		2
37 
38 /* MUX CSR */
39 #define SATA_ENET_CONFIG_REG		0x00000000
40 #define  CFG_SATA_ENET_SELECT_MASK	0x00000001
41 
42 /* SATA core host controller CSR */
43 #define SLVRDERRATTRIBUTES		0x00000000
44 #define SLVWRERRATTRIBUTES		0x00000004
45 #define MSTRDERRATTRIBUTES		0x00000008
46 #define MSTWRERRATTRIBUTES		0x0000000c
47 #define BUSCTLREG			0x00000014
48 #define IOFMSTRWAUX			0x00000018
49 #define INTSTATUSMASK			0x0000002c
50 #define ERRINTSTATUS			0x00000030
51 #define ERRINTSTATUSMASK		0x00000034
52 
53 /* SATA host AHCI CSR */
54 #define PORTCFG				0x000000a4
55 #define  PORTADDR_SET(dst, src) \
56 		(((dst) & ~0x0000003f) | (((u32)(src)) & 0x0000003f))
57 #define PORTPHY1CFG		0x000000a8
58 #define PORTPHY1CFG_FRCPHYRDY_SET(dst, src) \
59 		(((dst) & ~0x00100000) | (((u32)(src) << 0x14) & 0x00100000))
60 #define PORTPHY2CFG			0x000000ac
61 #define PORTPHY3CFG			0x000000b0
62 #define PORTPHY4CFG			0x000000b4
63 #define PORTPHY5CFG			0x000000b8
64 #define SCTL0				0x0000012C
65 #define PORTPHY5CFG_RTCHG_SET(dst, src) \
66 		(((dst) & ~0xfff00000) | (((u32)(src) << 0x14) & 0xfff00000))
67 #define PORTAXICFG_EN_CONTEXT_SET(dst, src) \
68 		(((dst) & ~0x01000000) | (((u32)(src) << 0x18) & 0x01000000))
69 #define PORTAXICFG			0x000000bc
70 #define PORTAXICFG_OUTTRANS_SET(dst, src) \
71 		(((dst) & ~0x00f00000) | (((u32)(src) << 0x14) & 0x00f00000))
72 #define PORTRANSCFG			0x000000c8
73 #define PORTRANSCFG_RXWM_SET(dst, src)		\
74 		(((dst) & ~0x0000007f) | (((u32)(src)) & 0x0000007f))
75 
76 /* SATA host controller AXI CSR */
77 #define INT_SLV_TMOMASK			0x00000010
78 
79 /* SATA diagnostic CSR */
80 #define CFG_MEM_RAM_SHUTDOWN		0x00000070
81 #define BLOCK_MEM_RDY			0x00000074
82 
83 /* Max retry for link down */
84 #define MAX_LINK_DOWN_RETRY 3
85 
86 struct xgene_ahci_context {
87 	struct ahci_host_priv *hpriv;
88 	struct device *dev;
89 	u8 last_cmd[MAX_AHCI_CHN_PERCTR]; /* tracking the last command issued*/
90 	u32 class[MAX_AHCI_CHN_PERCTR]; /* tracking the class of device */
91 	void __iomem *csr_core;		/* Core CSR address of IP */
92 	void __iomem *csr_diag;		/* Diag CSR address of IP */
93 	void __iomem *csr_axi;		/* AXI CSR address of IP */
94 	void __iomem *csr_mux;		/* MUX CSR address of IP */
95 };
96 
97 static int xgene_ahci_init_memram(struct xgene_ahci_context *ctx)
98 {
99 	dev_dbg(ctx->dev, "Release memory from shutdown\n");
100 	writel(0x0, ctx->csr_diag + CFG_MEM_RAM_SHUTDOWN);
101 	readl(ctx->csr_diag + CFG_MEM_RAM_SHUTDOWN); /* Force a barrier */
102 	msleep(1);	/* reset may take up to 1ms */
103 	if (readl(ctx->csr_diag + BLOCK_MEM_RDY) != 0xFFFFFFFF) {
104 		dev_err(ctx->dev, "failed to release memory from shutdown\n");
105 		return -ENODEV;
106 	}
107 	return 0;
108 }
109 
110 /**
111  * xgene_ahci_poll_reg_val- Poll a register on a specific value.
112  * @ap : ATA port of interest.
113  * @reg : Register of interest.
114  * @val : Value to be attained.
115  * @interval : waiting interval for polling.
116  * @timeout : timeout for achieving the value.
117  */
118 static int xgene_ahci_poll_reg_val(struct ata_port *ap,
119 				   void __iomem *reg, unsigned
120 				   int val, unsigned long interval,
121 				   unsigned long timeout)
122 {
123 	unsigned long deadline;
124 	unsigned int tmp;
125 
126 	tmp = ioread32(reg);
127 	deadline = ata_deadline(jiffies, timeout);
128 
129 	while (tmp != val && time_before(jiffies, deadline)) {
130 		ata_msleep(ap, interval);
131 		tmp = ioread32(reg);
132 	}
133 
134 	return tmp;
135 }
136 
137 /**
138  * xgene_ahci_restart_engine - Restart the dma engine.
139  * @ap : ATA port of interest
140  *
141  * Waits for completion of multiple commands and restarts
142  * the DMA engine inside the controller.
143  */
144 static int xgene_ahci_restart_engine(struct ata_port *ap)
145 {
146 	struct ahci_host_priv *hpriv = ap->host->private_data;
147 	struct ahci_port_priv *pp = ap->private_data;
148 	void __iomem *port_mmio = ahci_port_base(ap);
149 	u32 fbs;
150 
151 	/*
152 	 * In case of PMP multiple IDENTIFY DEVICE commands can be
153 	 * issued inside PxCI. So need to poll PxCI for the
154 	 * completion of outstanding IDENTIFY DEVICE commands before
155 	 * we restart the DMA engine.
156 	 */
157 	if (xgene_ahci_poll_reg_val(ap, port_mmio +
158 				    PORT_CMD_ISSUE, 0x0, 1, 100))
159 		  return -EBUSY;
160 
161 	ahci_stop_engine(ap);
162 	ahci_start_fis_rx(ap);
163 
164 	/*
165 	 * Enable the PxFBS.FBS_EN bit as it
166 	 * gets cleared due to stopping the engine.
167 	 */
168 	if (pp->fbs_supported) {
169 		fbs = readl(port_mmio + PORT_FBS);
170 		writel(fbs | PORT_FBS_EN, port_mmio + PORT_FBS);
171 		fbs = readl(port_mmio + PORT_FBS);
172 	}
173 
174 	hpriv->start_engine(ap);
175 
176 	return 0;
177 }
178 
179 /**
180  * xgene_ahci_qc_issue - Issue commands to the device
181  * @qc: Command to issue
182  *
183  * Due to Hardware errata for IDENTIFY DEVICE command, the controller cannot
184  * clear the BSY bit after receiving the PIO setup FIS. This results in the dma
185  * state machine goes into the CMFatalErrorUpdate state and locks up. By
186  * restarting the dma engine, it removes the controller out of lock up state.
187  *
188  * Due to H/W errata, the controller is unable to save the PMP
189  * field fetched from command header before sending the H2D FIS.
190  * When the device returns the PMP port field in the D2H FIS, there is
191  * a mismatch and results in command completion failure. The
192  * workaround is to write the pmp value to PxFBS.DEV field before issuing
193  * any command to PMP.
194  */
195 static unsigned int xgene_ahci_qc_issue(struct ata_queued_cmd *qc)
196 {
197 	struct ata_port *ap = qc->ap;
198 	struct ahci_host_priv *hpriv = ap->host->private_data;
199 	struct xgene_ahci_context *ctx = hpriv->plat_data;
200 	int rc = 0;
201 	u32 port_fbs;
202 	void *port_mmio = ahci_port_base(ap);
203 
204 	/*
205 	 * Write the pmp value to PxFBS.DEV
206 	 * for case of Port Mulitplier.
207 	 */
208 	if (ctx->class[ap->port_no] == ATA_DEV_PMP) {
209 		port_fbs = readl(port_mmio + PORT_FBS);
210 		port_fbs &= ~PORT_FBS_DEV_MASK;
211 		port_fbs |= qc->dev->link->pmp << PORT_FBS_DEV_OFFSET;
212 		writel(port_fbs, port_mmio + PORT_FBS);
213 	}
214 
215 	if (unlikely((ctx->last_cmd[ap->port_no] == ATA_CMD_ID_ATA) ||
216 	    (ctx->last_cmd[ap->port_no] == ATA_CMD_PACKET) ||
217 	    (ctx->last_cmd[ap->port_no] == ATA_CMD_SMART)))
218 		xgene_ahci_restart_engine(ap);
219 
220 	rc = ahci_qc_issue(qc);
221 
222 	/* Save the last command issued */
223 	ctx->last_cmd[ap->port_no] = qc->tf.command;
224 
225 	return rc;
226 }
227 
228 static bool xgene_ahci_is_memram_inited(struct xgene_ahci_context *ctx)
229 {
230 	void __iomem *diagcsr = ctx->csr_diag;
231 
232 	return (readl(diagcsr + CFG_MEM_RAM_SHUTDOWN) == 0 &&
233 	        readl(diagcsr + BLOCK_MEM_RDY) == 0xFFFFFFFF);
234 }
235 
236 /**
237  * xgene_ahci_read_id - Read ID data from the specified device
238  * @dev: device
239  * @tf: proposed taskfile
240  * @id: data buffer
241  *
242  * This custom read ID function is required due to the fact that the HW
243  * does not support DEVSLP.
244  */
245 static unsigned int xgene_ahci_read_id(struct ata_device *dev,
246 				       struct ata_taskfile *tf, u16 *id)
247 {
248 	u32 err_mask;
249 
250 	err_mask = ata_do_dev_read_id(dev, tf, id);
251 	if (err_mask)
252 		return err_mask;
253 
254 	/*
255 	 * Mask reserved area. Word78 spec of Link Power Management
256 	 * bit15-8: reserved
257 	 * bit7: NCQ autosence
258 	 * bit6: Software settings preservation supported
259 	 * bit5: reserved
260 	 * bit4: In-order sata delivery supported
261 	 * bit3: DIPM requests supported
262 	 * bit2: DMA Setup FIS Auto-Activate optimization supported
263 	 * bit1: DMA Setup FIX non-Zero buffer offsets supported
264 	 * bit0: Reserved
265 	 *
266 	 * Clear reserved bit 8 (DEVSLP bit) as we don't support DEVSLP
267 	 */
268 	id[ATA_ID_FEATURE_SUPP] &= cpu_to_le16(~(1 << 8));
269 
270 	return 0;
271 }
272 
273 static void xgene_ahci_set_phy_cfg(struct xgene_ahci_context *ctx, int channel)
274 {
275 	void __iomem *mmio = ctx->hpriv->mmio;
276 	u32 val;
277 
278 	dev_dbg(ctx->dev, "port configure mmio 0x%p channel %d\n",
279 		mmio, channel);
280 	val = readl(mmio + PORTCFG);
281 	val = PORTADDR_SET(val, channel == 0 ? 2 : 3);
282 	writel(val, mmio + PORTCFG);
283 	readl(mmio + PORTCFG);  /* Force a barrier */
284 	/* Disable fix rate */
285 	writel(0x0001fffe, mmio + PORTPHY1CFG);
286 	readl(mmio + PORTPHY1CFG); /* Force a barrier */
287 	writel(0x28183219, mmio + PORTPHY2CFG);
288 	readl(mmio + PORTPHY2CFG); /* Force a barrier */
289 	writel(0x13081008, mmio + PORTPHY3CFG);
290 	readl(mmio + PORTPHY3CFG); /* Force a barrier */
291 	writel(0x00480815, mmio + PORTPHY4CFG);
292 	readl(mmio + PORTPHY4CFG); /* Force a barrier */
293 	/* Set window negotiation */
294 	val = readl(mmio + PORTPHY5CFG);
295 	val = PORTPHY5CFG_RTCHG_SET(val, 0x300);
296 	writel(val, mmio + PORTPHY5CFG);
297 	readl(mmio + PORTPHY5CFG); /* Force a barrier */
298 	val = readl(mmio + PORTAXICFG);
299 	val = PORTAXICFG_EN_CONTEXT_SET(val, 0x1); /* Enable context mgmt */
300 	val = PORTAXICFG_OUTTRANS_SET(val, 0xe); /* Set outstanding */
301 	writel(val, mmio + PORTAXICFG);
302 	readl(mmio + PORTAXICFG); /* Force a barrier */
303 	/* Set the watermark threshold of the receive FIFO */
304 	val = readl(mmio + PORTRANSCFG);
305 	val = PORTRANSCFG_RXWM_SET(val, 0x30);
306 	writel(val, mmio + PORTRANSCFG);
307 }
308 
309 /**
310  * xgene_ahci_do_hardreset - Issue the actual COMRESET
311  * @link: link to reset
312  * @deadline: deadline jiffies for the operation
313  * @online: Return value to indicate if device online
314  *
315  * Due to the limitation of the hardware PHY, a difference set of setting is
316  * required for each supported disk speed - Gen3 (6.0Gbps), Gen2 (3.0Gbps),
317  * and Gen1 (1.5Gbps). Otherwise during long IO stress test, the PHY will
318  * report disparity error and etc. In addition, during COMRESET, there can
319  * be error reported in the register PORT_SCR_ERR. For SERR_DISPARITY and
320  * SERR_10B_8B_ERR, the PHY receiver line must be reseted. Also during long
321  * reboot cycle regression, sometimes the PHY reports link down even if the
322  * device is present because of speed negotiation failure. so need to retry
323  * the COMRESET to get the link up. The following algorithm is followed to
324  * proper configure the hardware PHY during COMRESET:
325  *
326  * Alg Part 1:
327  * 1. Start the PHY at Gen3 speed (default setting)
328  * 2. Issue the COMRESET
329  * 3. If no link, go to Alg Part 3
330  * 4. If link up, determine if the negotiated speed matches the PHY
331  *    configured speed
332  * 5. If they matched, go to Alg Part 2
333  * 6. If they do not matched and first time, configure the PHY for the linked
334  *    up disk speed and repeat step 2
335  * 7. Go to Alg Part 2
336  *
337  * Alg Part 2:
338  * 1. On link up, if there are any SERR_DISPARITY and SERR_10B_8B_ERR error
339  *    reported in the register PORT_SCR_ERR, then reset the PHY receiver line
340  * 2. Go to Alg Part 4
341  *
342  * Alg Part 3:
343  * 1. Check the PORT_SCR_STAT to see whether device presence detected but PHY
344  *    communication establishment failed and maximum link down attempts are
345  *    less than Max attempts 3 then goto Alg Part 1.
346  * 2. Go to Alg Part 4.
347  *
348  * Alg Part 4:
349  * 1. Clear any pending from register PORT_SCR_ERR.
350  *
351  * NOTE: For the initial version, we will NOT support Gen1/Gen2. In addition
352  *       and until the underlying PHY supports an method to reset the receiver
353  *       line, on detection of SERR_DISPARITY or SERR_10B_8B_ERR errors,
354  *       an warning message will be printed.
355  */
356 static int xgene_ahci_do_hardreset(struct ata_link *link,
357 				   unsigned long deadline, bool *online)
358 {
359 	const unsigned long *timing = sata_ehc_deb_timing(&link->eh_context);
360 	struct ata_port *ap = link->ap;
361 	struct ahci_host_priv *hpriv = ap->host->private_data;
362 	struct xgene_ahci_context *ctx = hpriv->plat_data;
363 	struct ahci_port_priv *pp = ap->private_data;
364 	u8 *d2h_fis = pp->rx_fis + RX_FIS_D2H_REG;
365 	void __iomem *port_mmio = ahci_port_base(ap);
366 	struct ata_taskfile tf;
367 	int link_down_retry = 0;
368 	int rc;
369 	u32 val, sstatus;
370 
371 	do {
372 		/* clear D2H reception area to properly wait for D2H FIS */
373 		ata_tf_init(link->device, &tf);
374 		tf.command = ATA_BUSY;
375 		ata_tf_to_fis(&tf, 0, 0, d2h_fis);
376 		rc = sata_link_hardreset(link, timing, deadline, online,
377 				 ahci_check_ready);
378 		if (*online) {
379 			val = readl(port_mmio + PORT_SCR_ERR);
380 			if (val & (SERR_DISPARITY | SERR_10B_8B_ERR))
381 				dev_warn(ctx->dev, "link has error\n");
382 			break;
383 		}
384 
385 		sata_scr_read(link, SCR_STATUS, &sstatus);
386 	} while (link_down_retry++ < MAX_LINK_DOWN_RETRY &&
387 		 (sstatus & 0xff) == 0x1);
388 
389 	/* clear all errors if any pending */
390 	val = readl(port_mmio + PORT_SCR_ERR);
391 	writel(val, port_mmio + PORT_SCR_ERR);
392 
393 	return rc;
394 }
395 
396 static int xgene_ahci_hardreset(struct ata_link *link, unsigned int *class,
397 				unsigned long deadline)
398 {
399 	struct ata_port *ap = link->ap;
400         struct ahci_host_priv *hpriv = ap->host->private_data;
401 	void __iomem *port_mmio = ahci_port_base(ap);
402 	bool online;
403 	int rc;
404 	u32 portcmd_saved;
405 	u32 portclb_saved;
406 	u32 portclbhi_saved;
407 	u32 portrxfis_saved;
408 	u32 portrxfishi_saved;
409 
410 	/* As hardreset resets these CSR, save it to restore later */
411 	portcmd_saved = readl(port_mmio + PORT_CMD);
412 	portclb_saved = readl(port_mmio + PORT_LST_ADDR);
413 	portclbhi_saved = readl(port_mmio + PORT_LST_ADDR_HI);
414 	portrxfis_saved = readl(port_mmio + PORT_FIS_ADDR);
415 	portrxfishi_saved = readl(port_mmio + PORT_FIS_ADDR_HI);
416 
417 	ahci_stop_engine(ap);
418 
419 	rc = xgene_ahci_do_hardreset(link, deadline, &online);
420 
421 	/* As controller hardreset clears them, restore them */
422 	writel(portcmd_saved, port_mmio + PORT_CMD);
423 	writel(portclb_saved, port_mmio + PORT_LST_ADDR);
424 	writel(portclbhi_saved, port_mmio + PORT_LST_ADDR_HI);
425 	writel(portrxfis_saved, port_mmio + PORT_FIS_ADDR);
426 	writel(portrxfishi_saved, port_mmio + PORT_FIS_ADDR_HI);
427 
428 	hpriv->start_engine(ap);
429 
430 	if (online)
431 		*class = ahci_dev_classify(ap);
432 
433 	return rc;
434 }
435 
436 static void xgene_ahci_host_stop(struct ata_host *host)
437 {
438 	struct ahci_host_priv *hpriv = host->private_data;
439 
440 	ahci_platform_disable_resources(hpriv);
441 }
442 
443 /**
444  * xgene_ahci_pmp_softreset - Issue the softreset to the drives connected
445  *                            to Port Multiplier.
446  * @link: link to reset
447  * @class: Return value to indicate class of device
448  * @deadline: deadline jiffies for the operation
449  *
450  * Due to H/W errata, the controller is unable to save the PMP
451  * field fetched from command header before sending the H2D FIS.
452  * When the device returns the PMP port field in the D2H FIS, there is
453  * a mismatch and results in command completion failure. The workaround
454  * is to write the pmp value to PxFBS.DEV field before issuing any command
455  * to PMP.
456  */
457 static int xgene_ahci_pmp_softreset(struct ata_link *link, unsigned int *class,
458 			  unsigned long deadline)
459 {
460 	int pmp = sata_srst_pmp(link);
461 	struct ata_port *ap = link->ap;
462 	u32 rc;
463 	void *port_mmio = ahci_port_base(ap);
464 	u32 port_fbs;
465 
466 	/*
467 	 * Set PxFBS.DEV field with pmp
468 	 * value.
469 	 */
470 	port_fbs = readl(port_mmio + PORT_FBS);
471 	port_fbs &= ~PORT_FBS_DEV_MASK;
472 	port_fbs |= pmp << PORT_FBS_DEV_OFFSET;
473 	writel(port_fbs, port_mmio + PORT_FBS);
474 
475 	rc = ahci_do_softreset(link, class, pmp, deadline, ahci_check_ready);
476 
477 	return rc;
478 }
479 
480 /**
481  * xgene_ahci_softreset - Issue the softreset to the drive.
482  * @link: link to reset
483  * @class: Return value to indicate class of device
484  * @deadline: deadline jiffies for the operation
485  *
486  * Due to H/W errata, the controller is unable to save the PMP
487  * field fetched from command header before sending the H2D FIS.
488  * When the device returns the PMP port field in the D2H FIS, there is
489  * a mismatch and results in command completion failure. The workaround
490  * is to write the pmp value to PxFBS.DEV field before issuing any command
491  * to PMP. Here is the algorithm to detect PMP :
492  *
493  * 1. Save the PxFBS value
494  * 2. Program PxFBS.DEV with pmp value send by framework. Framework sends
495  *    0xF for both PMP/NON-PMP initially
496  * 3. Issue softreset
497  * 4. If signature class is PMP goto 6
498  * 5. restore the original PxFBS and goto 3
499  * 6. return
500  */
501 static int xgene_ahci_softreset(struct ata_link *link, unsigned int *class,
502 			  unsigned long deadline)
503 {
504 	int pmp = sata_srst_pmp(link);
505 	struct ata_port *ap = link->ap;
506 	struct ahci_host_priv *hpriv = ap->host->private_data;
507 	struct xgene_ahci_context *ctx = hpriv->plat_data;
508 	void *port_mmio = ahci_port_base(ap);
509 	u32 port_fbs;
510 	u32 port_fbs_save;
511 	u32 retry = 1;
512 	u32 rc;
513 
514 	port_fbs_save = readl(port_mmio + PORT_FBS);
515 
516 	/*
517 	 * Set PxFBS.DEV field with pmp
518 	 * value.
519 	 */
520 	port_fbs = readl(port_mmio + PORT_FBS);
521 	port_fbs &= ~PORT_FBS_DEV_MASK;
522 	port_fbs |= pmp << PORT_FBS_DEV_OFFSET;
523 	writel(port_fbs, port_mmio + PORT_FBS);
524 
525 softreset_retry:
526 	rc = ahci_do_softreset(link, class, pmp,
527 			       deadline, ahci_check_ready);
528 
529 	ctx->class[ap->port_no] = *class;
530 	if (*class != ATA_DEV_PMP) {
531 		/*
532 		 * Retry for normal drives without
533 		 * setting PxFBS.DEV field with pmp value.
534 		 */
535 		if (retry--) {
536 			writel(port_fbs_save, port_mmio + PORT_FBS);
537 			goto softreset_retry;
538 		}
539 	}
540 
541 	return rc;
542 }
543 
544 static struct ata_port_operations xgene_ahci_ops = {
545 	.inherits = &ahci_ops,
546 	.host_stop = xgene_ahci_host_stop,
547 	.hardreset = xgene_ahci_hardreset,
548 	.read_id = xgene_ahci_read_id,
549 	.qc_issue = xgene_ahci_qc_issue,
550 	.softreset = xgene_ahci_softreset,
551 	.pmp_softreset = xgene_ahci_pmp_softreset
552 };
553 
554 static const struct ata_port_info xgene_ahci_port_info = {
555 	.flags = AHCI_FLAG_COMMON | ATA_FLAG_PMP,
556 	.pio_mask = ATA_PIO4,
557 	.udma_mask = ATA_UDMA6,
558 	.port_ops = &xgene_ahci_ops,
559 };
560 
561 static int xgene_ahci_hw_init(struct ahci_host_priv *hpriv)
562 {
563 	struct xgene_ahci_context *ctx = hpriv->plat_data;
564 	int i;
565 	int rc;
566 	u32 val;
567 
568 	/* Remove IP RAM out of shutdown */
569 	rc = xgene_ahci_init_memram(ctx);
570 	if (rc)
571 		return rc;
572 
573 	for (i = 0; i < MAX_AHCI_CHN_PERCTR; i++)
574 		xgene_ahci_set_phy_cfg(ctx, i);
575 
576 	/* AXI disable Mask */
577 	writel(0xffffffff, hpriv->mmio + HOST_IRQ_STAT);
578 	readl(hpriv->mmio + HOST_IRQ_STAT); /* Force a barrier */
579 	writel(0, ctx->csr_core + INTSTATUSMASK);
580 	val = readl(ctx->csr_core + INTSTATUSMASK); /* Force a barrier */
581 	dev_dbg(ctx->dev, "top level interrupt mask 0x%X value 0x%08X\n",
582 		INTSTATUSMASK, val);
583 
584 	writel(0x0, ctx->csr_core + ERRINTSTATUSMASK);
585 	readl(ctx->csr_core + ERRINTSTATUSMASK); /* Force a barrier */
586 	writel(0x0, ctx->csr_axi + INT_SLV_TMOMASK);
587 	readl(ctx->csr_axi + INT_SLV_TMOMASK);
588 
589 	/* Enable AXI Interrupt */
590 	writel(0xffffffff, ctx->csr_core + SLVRDERRATTRIBUTES);
591 	writel(0xffffffff, ctx->csr_core + SLVWRERRATTRIBUTES);
592 	writel(0xffffffff, ctx->csr_core + MSTRDERRATTRIBUTES);
593 	writel(0xffffffff, ctx->csr_core + MSTWRERRATTRIBUTES);
594 
595 	/* Enable coherency */
596 	val = readl(ctx->csr_core + BUSCTLREG);
597 	val &= ~0x00000002;     /* Enable write coherency */
598 	val &= ~0x00000001;     /* Enable read coherency */
599 	writel(val, ctx->csr_core + BUSCTLREG);
600 
601 	val = readl(ctx->csr_core + IOFMSTRWAUX);
602 	val |= (1 << 3);        /* Enable read coherency */
603 	val |= (1 << 9);        /* Enable write coherency */
604 	writel(val, ctx->csr_core + IOFMSTRWAUX);
605 	val = readl(ctx->csr_core + IOFMSTRWAUX);
606 	dev_dbg(ctx->dev, "coherency 0x%X value 0x%08X\n",
607 		IOFMSTRWAUX, val);
608 
609 	return rc;
610 }
611 
612 static int xgene_ahci_mux_select(struct xgene_ahci_context *ctx)
613 {
614 	u32 val;
615 
616 	/* Check for optional MUX resource */
617 	if (!ctx->csr_mux)
618 		return 0;
619 
620 	val = readl(ctx->csr_mux + SATA_ENET_CONFIG_REG);
621 	val &= ~CFG_SATA_ENET_SELECT_MASK;
622 	writel(val, ctx->csr_mux + SATA_ENET_CONFIG_REG);
623 	val = readl(ctx->csr_mux + SATA_ENET_CONFIG_REG);
624 	return val & CFG_SATA_ENET_SELECT_MASK ? -1 : 0;
625 }
626 
627 static struct scsi_host_template ahci_platform_sht = {
628 	AHCI_SHT(DRV_NAME),
629 };
630 
631 static int xgene_ahci_probe(struct platform_device *pdev)
632 {
633 	struct device *dev = &pdev->dev;
634 	struct ahci_host_priv *hpriv;
635 	struct xgene_ahci_context *ctx;
636 	struct resource *res;
637 	int rc;
638 
639 	hpriv = ahci_platform_get_resources(pdev);
640 	if (IS_ERR(hpriv))
641 		return PTR_ERR(hpriv);
642 
643 	ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
644 	if (!ctx)
645 		return -ENOMEM;
646 
647 	hpriv->plat_data = ctx;
648 	ctx->hpriv = hpriv;
649 	ctx->dev = dev;
650 
651 	/* Retrieve the IP core resource */
652 	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
653 	ctx->csr_core = devm_ioremap_resource(dev, res);
654 	if (IS_ERR(ctx->csr_core))
655 		return PTR_ERR(ctx->csr_core);
656 
657 	/* Retrieve the IP diagnostic resource */
658 	res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
659 	ctx->csr_diag = devm_ioremap_resource(dev, res);
660 	if (IS_ERR(ctx->csr_diag))
661 		return PTR_ERR(ctx->csr_diag);
662 
663 	/* Retrieve the IP AXI resource */
664 	res = platform_get_resource(pdev, IORESOURCE_MEM, 3);
665 	ctx->csr_axi = devm_ioremap_resource(dev, res);
666 	if (IS_ERR(ctx->csr_axi))
667 		return PTR_ERR(ctx->csr_axi);
668 
669 	/* Retrieve the optional IP mux resource */
670 	res = platform_get_resource(pdev, IORESOURCE_MEM, 4);
671 	if (res) {
672 		void __iomem *csr = devm_ioremap_resource(dev, res);
673 		if (IS_ERR(csr))
674 			return PTR_ERR(csr);
675 
676 		ctx->csr_mux = csr;
677 	}
678 
679 	dev_dbg(dev, "VAddr 0x%p Mmio VAddr 0x%p\n", ctx->csr_core,
680 		hpriv->mmio);
681 
682 	/* Select ATA */
683 	if ((rc = xgene_ahci_mux_select(ctx))) {
684 		dev_err(dev, "SATA mux selection failed error %d\n", rc);
685 		return -ENODEV;
686 	}
687 
688 	if (xgene_ahci_is_memram_inited(ctx)) {
689 		dev_info(dev, "skip clock and PHY initialization\n");
690 		goto skip_clk_phy;
691 	}
692 
693 	/* Due to errata, HW requires full toggle transition */
694 	rc = ahci_platform_enable_clks(hpriv);
695 	if (rc)
696 		goto disable_resources;
697 	ahci_platform_disable_clks(hpriv);
698 
699 	rc = ahci_platform_enable_resources(hpriv);
700 	if (rc)
701 		goto disable_resources;
702 
703 	/* Configure the host controller */
704 	xgene_ahci_hw_init(hpriv);
705 skip_clk_phy:
706 	hpriv->flags = AHCI_HFLAG_NO_PMP | AHCI_HFLAG_NO_NCQ;
707 
708 	rc = ahci_platform_init_host(pdev, hpriv, &xgene_ahci_port_info,
709 				     &ahci_platform_sht);
710 	if (rc)
711 		goto disable_resources;
712 
713 	dev_dbg(dev, "X-Gene SATA host controller initialized\n");
714 	return 0;
715 
716 disable_resources:
717 	ahci_platform_disable_resources(hpriv);
718 	return rc;
719 }
720 
721 static const struct of_device_id xgene_ahci_of_match[] = {
722 	{.compatible = "apm,xgene-ahci"},
723 	{},
724 };
725 MODULE_DEVICE_TABLE(of, xgene_ahci_of_match);
726 
727 static struct platform_driver xgene_ahci_driver = {
728 	.probe = xgene_ahci_probe,
729 	.remove = ata_platform_remove_one,
730 	.driver = {
731 		.name = DRV_NAME,
732 		.of_match_table = xgene_ahci_of_match,
733 	},
734 };
735 
736 module_platform_driver(xgene_ahci_driver);
737 
738 MODULE_DESCRIPTION("APM X-Gene AHCI SATA driver");
739 MODULE_AUTHOR("Loc Ho <lho@apm.com>");
740 MODULE_LICENSE("GPL");
741 MODULE_VERSION("0.4");
742