xref: /openbmc/linux/drivers/ata/ahci_xgene.c (revision 829c6524)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * AppliedMicro X-Gene SoC SATA Host Controller Driver
4  *
5  * Copyright (c) 2014, Applied Micro Circuits Corporation
6  * Author: Loc Ho <lho@apm.com>
7  *         Tuan Phan <tphan@apm.com>
8  *         Suman Tripathi <stripathi@apm.com>
9  *
10  * NOTE: PM support is not currently available.
11  */
12 #include <linux/acpi.h>
13 #include <linux/module.h>
14 #include <linux/platform_device.h>
15 #include <linux/ahci_platform.h>
16 #include <linux/of_address.h>
17 #include <linux/of_device.h>
18 #include <linux/of_irq.h>
19 #include <linux/phy/phy.h>
20 #include "ahci.h"
21 
22 #define DRV_NAME "xgene-ahci"
23 
24 /* Max # of disk per a controller */
25 #define MAX_AHCI_CHN_PERCTR		2
26 
27 /* MUX CSR */
28 #define SATA_ENET_CONFIG_REG		0x00000000
29 #define  CFG_SATA_ENET_SELECT_MASK	0x00000001
30 
31 /* SATA core host controller CSR */
32 #define SLVRDERRATTRIBUTES		0x00000000
33 #define SLVWRERRATTRIBUTES		0x00000004
34 #define MSTRDERRATTRIBUTES		0x00000008
35 #define MSTWRERRATTRIBUTES		0x0000000c
36 #define BUSCTLREG			0x00000014
37 #define IOFMSTRWAUX			0x00000018
38 #define INTSTATUSMASK			0x0000002c
39 #define ERRINTSTATUS			0x00000030
40 #define ERRINTSTATUSMASK		0x00000034
41 
42 /* SATA host AHCI CSR */
43 #define PORTCFG				0x000000a4
44 #define  PORTADDR_SET(dst, src) \
45 		(((dst) & ~0x0000003f) | (((u32)(src)) & 0x0000003f))
46 #define PORTPHY1CFG		0x000000a8
47 #define PORTPHY1CFG_FRCPHYRDY_SET(dst, src) \
48 		(((dst) & ~0x00100000) | (((u32)(src) << 0x14) & 0x00100000))
49 #define PORTPHY2CFG			0x000000ac
50 #define PORTPHY3CFG			0x000000b0
51 #define PORTPHY4CFG			0x000000b4
52 #define PORTPHY5CFG			0x000000b8
53 #define SCTL0				0x0000012C
54 #define PORTPHY5CFG_RTCHG_SET(dst, src) \
55 		(((dst) & ~0xfff00000) | (((u32)(src) << 0x14) & 0xfff00000))
56 #define PORTAXICFG_EN_CONTEXT_SET(dst, src) \
57 		(((dst) & ~0x01000000) | (((u32)(src) << 0x18) & 0x01000000))
58 #define PORTAXICFG			0x000000bc
59 #define PORTAXICFG_OUTTRANS_SET(dst, src) \
60 		(((dst) & ~0x00f00000) | (((u32)(src) << 0x14) & 0x00f00000))
61 #define PORTRANSCFG			0x000000c8
62 #define PORTRANSCFG_RXWM_SET(dst, src)		\
63 		(((dst) & ~0x0000007f) | (((u32)(src)) & 0x0000007f))
64 
65 /* SATA host controller AXI CSR */
66 #define INT_SLV_TMOMASK			0x00000010
67 
68 /* SATA diagnostic CSR */
69 #define CFG_MEM_RAM_SHUTDOWN		0x00000070
70 #define BLOCK_MEM_RDY			0x00000074
71 
72 /* Max retry for link down */
73 #define MAX_LINK_DOWN_RETRY 3
74 
75 enum xgene_ahci_version {
76 	XGENE_AHCI_V1 = 1,
77 	XGENE_AHCI_V2,
78 };
79 
80 struct xgene_ahci_context {
81 	struct ahci_host_priv *hpriv;
82 	struct device *dev;
83 	u8 last_cmd[MAX_AHCI_CHN_PERCTR]; /* tracking the last command issued*/
84 	u32 class[MAX_AHCI_CHN_PERCTR]; /* tracking the class of device */
85 	void __iomem *csr_core;		/* Core CSR address of IP */
86 	void __iomem *csr_diag;		/* Diag CSR address of IP */
87 	void __iomem *csr_axi;		/* AXI CSR address of IP */
88 	void __iomem *csr_mux;		/* MUX CSR address of IP */
89 };
90 
91 static int xgene_ahci_init_memram(struct xgene_ahci_context *ctx)
92 {
93 	dev_dbg(ctx->dev, "Release memory from shutdown\n");
94 	writel(0x0, ctx->csr_diag + CFG_MEM_RAM_SHUTDOWN);
95 	readl(ctx->csr_diag + CFG_MEM_RAM_SHUTDOWN); /* Force a barrier */
96 	msleep(1);	/* reset may take up to 1ms */
97 	if (readl(ctx->csr_diag + BLOCK_MEM_RDY) != 0xFFFFFFFF) {
98 		dev_err(ctx->dev, "failed to release memory from shutdown\n");
99 		return -ENODEV;
100 	}
101 	return 0;
102 }
103 
104 /**
105  * xgene_ahci_poll_reg_val- Poll a register on a specific value.
106  * @ap : ATA port of interest.
107  * @reg : Register of interest.
108  * @val : Value to be attained.
109  * @interval : waiting interval for polling.
110  * @timeout : timeout for achieving the value.
111  */
112 static int xgene_ahci_poll_reg_val(struct ata_port *ap,
113 				   void __iomem *reg, unsigned
114 				   int val, unsigned long interval,
115 				   unsigned long timeout)
116 {
117 	unsigned long deadline;
118 	unsigned int tmp;
119 
120 	tmp = ioread32(reg);
121 	deadline = ata_deadline(jiffies, timeout);
122 
123 	while (tmp != val && time_before(jiffies, deadline)) {
124 		ata_msleep(ap, interval);
125 		tmp = ioread32(reg);
126 	}
127 
128 	return tmp;
129 }
130 
131 /**
132  * xgene_ahci_restart_engine - Restart the dma engine.
133  * @ap : ATA port of interest
134  *
135  * Waits for completion of multiple commands and restarts
136  * the DMA engine inside the controller.
137  */
138 static int xgene_ahci_restart_engine(struct ata_port *ap)
139 {
140 	struct ahci_host_priv *hpriv = ap->host->private_data;
141 	struct ahci_port_priv *pp = ap->private_data;
142 	void __iomem *port_mmio = ahci_port_base(ap);
143 	u32 fbs;
144 
145 	/*
146 	 * In case of PMP multiple IDENTIFY DEVICE commands can be
147 	 * issued inside PxCI. So need to poll PxCI for the
148 	 * completion of outstanding IDENTIFY DEVICE commands before
149 	 * we restart the DMA engine.
150 	 */
151 	if (xgene_ahci_poll_reg_val(ap, port_mmio +
152 				    PORT_CMD_ISSUE, 0x0, 1, 100))
153 		  return -EBUSY;
154 
155 	hpriv->stop_engine(ap);
156 	ahci_start_fis_rx(ap);
157 
158 	/*
159 	 * Enable the PxFBS.FBS_EN bit as it
160 	 * gets cleared due to stopping the engine.
161 	 */
162 	if (pp->fbs_supported) {
163 		fbs = readl(port_mmio + PORT_FBS);
164 		writel(fbs | PORT_FBS_EN, port_mmio + PORT_FBS);
165 		fbs = readl(port_mmio + PORT_FBS);
166 	}
167 
168 	hpriv->start_engine(ap);
169 
170 	return 0;
171 }
172 
173 /**
174  * xgene_ahci_qc_issue - Issue commands to the device
175  * @qc: Command to issue
176  *
177  * Due to Hardware errata for IDENTIFY DEVICE command, the controller cannot
178  * clear the BSY bit after receiving the PIO setup FIS. This results in the dma
179  * state machine goes into the CMFatalErrorUpdate state and locks up. By
180  * restarting the dma engine, it removes the controller out of lock up state.
181  *
182  * Due to H/W errata, the controller is unable to save the PMP
183  * field fetched from command header before sending the H2D FIS.
184  * When the device returns the PMP port field in the D2H FIS, there is
185  * a mismatch and results in command completion failure. The
186  * workaround is to write the pmp value to PxFBS.DEV field before issuing
187  * any command to PMP.
188  */
189 static unsigned int xgene_ahci_qc_issue(struct ata_queued_cmd *qc)
190 {
191 	struct ata_port *ap = qc->ap;
192 	struct ahci_host_priv *hpriv = ap->host->private_data;
193 	struct xgene_ahci_context *ctx = hpriv->plat_data;
194 	int rc = 0;
195 	u32 port_fbs;
196 	void __iomem *port_mmio = ahci_port_base(ap);
197 
198 	/*
199 	 * Write the pmp value to PxFBS.DEV
200 	 * for case of Port Mulitplier.
201 	 */
202 	if (ctx->class[ap->port_no] == ATA_DEV_PMP) {
203 		port_fbs = readl(port_mmio + PORT_FBS);
204 		port_fbs &= ~PORT_FBS_DEV_MASK;
205 		port_fbs |= qc->dev->link->pmp << PORT_FBS_DEV_OFFSET;
206 		writel(port_fbs, port_mmio + PORT_FBS);
207 	}
208 
209 	if (unlikely((ctx->last_cmd[ap->port_no] == ATA_CMD_ID_ATA) ||
210 	    (ctx->last_cmd[ap->port_no] == ATA_CMD_PACKET) ||
211 	    (ctx->last_cmd[ap->port_no] == ATA_CMD_SMART)))
212 		xgene_ahci_restart_engine(ap);
213 
214 	rc = ahci_qc_issue(qc);
215 
216 	/* Save the last command issued */
217 	ctx->last_cmd[ap->port_no] = qc->tf.command;
218 
219 	return rc;
220 }
221 
222 static bool xgene_ahci_is_memram_inited(struct xgene_ahci_context *ctx)
223 {
224 	void __iomem *diagcsr = ctx->csr_diag;
225 
226 	return (readl(diagcsr + CFG_MEM_RAM_SHUTDOWN) == 0 &&
227 	        readl(diagcsr + BLOCK_MEM_RDY) == 0xFFFFFFFF);
228 }
229 
230 /**
231  * xgene_ahci_read_id - Read ID data from the specified device
232  * @dev: device
233  * @tf: proposed taskfile
234  * @id: data buffer
235  *
236  * This custom read ID function is required due to the fact that the HW
237  * does not support DEVSLP.
238  */
239 static unsigned int xgene_ahci_read_id(struct ata_device *dev,
240 				       struct ata_taskfile *tf, __le16 *id)
241 {
242 	u32 err_mask;
243 
244 	err_mask = ata_do_dev_read_id(dev, tf, id);
245 	if (err_mask)
246 		return err_mask;
247 
248 	/*
249 	 * Mask reserved area. Word78 spec of Link Power Management
250 	 * bit15-8: reserved
251 	 * bit7: NCQ autosence
252 	 * bit6: Software settings preservation supported
253 	 * bit5: reserved
254 	 * bit4: In-order sata delivery supported
255 	 * bit3: DIPM requests supported
256 	 * bit2: DMA Setup FIS Auto-Activate optimization supported
257 	 * bit1: DMA Setup FIX non-Zero buffer offsets supported
258 	 * bit0: Reserved
259 	 *
260 	 * Clear reserved bit 8 (DEVSLP bit) as we don't support DEVSLP
261 	 */
262 	id[ATA_ID_FEATURE_SUPP] &= cpu_to_le16(~(1 << 8));
263 
264 	return 0;
265 }
266 
267 static void xgene_ahci_set_phy_cfg(struct xgene_ahci_context *ctx, int channel)
268 {
269 	void __iomem *mmio = ctx->hpriv->mmio;
270 	u32 val;
271 
272 	dev_dbg(ctx->dev, "port configure mmio 0x%p channel %d\n",
273 		mmio, channel);
274 	val = readl(mmio + PORTCFG);
275 	val = PORTADDR_SET(val, channel == 0 ? 2 : 3);
276 	writel(val, mmio + PORTCFG);
277 	readl(mmio + PORTCFG);  /* Force a barrier */
278 	/* Disable fix rate */
279 	writel(0x0001fffe, mmio + PORTPHY1CFG);
280 	readl(mmio + PORTPHY1CFG); /* Force a barrier */
281 	writel(0x28183219, mmio + PORTPHY2CFG);
282 	readl(mmio + PORTPHY2CFG); /* Force a barrier */
283 	writel(0x13081008, mmio + PORTPHY3CFG);
284 	readl(mmio + PORTPHY3CFG); /* Force a barrier */
285 	writel(0x00480815, mmio + PORTPHY4CFG);
286 	readl(mmio + PORTPHY4CFG); /* Force a barrier */
287 	/* Set window negotiation */
288 	val = readl(mmio + PORTPHY5CFG);
289 	val = PORTPHY5CFG_RTCHG_SET(val, 0x300);
290 	writel(val, mmio + PORTPHY5CFG);
291 	readl(mmio + PORTPHY5CFG); /* Force a barrier */
292 	val = readl(mmio + PORTAXICFG);
293 	val = PORTAXICFG_EN_CONTEXT_SET(val, 0x1); /* Enable context mgmt */
294 	val = PORTAXICFG_OUTTRANS_SET(val, 0xe); /* Set outstanding */
295 	writel(val, mmio + PORTAXICFG);
296 	readl(mmio + PORTAXICFG); /* Force a barrier */
297 	/* Set the watermark threshold of the receive FIFO */
298 	val = readl(mmio + PORTRANSCFG);
299 	val = PORTRANSCFG_RXWM_SET(val, 0x30);
300 	writel(val, mmio + PORTRANSCFG);
301 }
302 
303 /**
304  * xgene_ahci_do_hardreset - Issue the actual COMRESET
305  * @link: link to reset
306  * @deadline: deadline jiffies for the operation
307  * @online: Return value to indicate if device online
308  *
309  * Due to the limitation of the hardware PHY, a difference set of setting is
310  * required for each supported disk speed - Gen3 (6.0Gbps), Gen2 (3.0Gbps),
311  * and Gen1 (1.5Gbps). Otherwise during long IO stress test, the PHY will
312  * report disparity error and etc. In addition, during COMRESET, there can
313  * be error reported in the register PORT_SCR_ERR. For SERR_DISPARITY and
314  * SERR_10B_8B_ERR, the PHY receiver line must be reseted. Also during long
315  * reboot cycle regression, sometimes the PHY reports link down even if the
316  * device is present because of speed negotiation failure. so need to retry
317  * the COMRESET to get the link up. The following algorithm is followed to
318  * proper configure the hardware PHY during COMRESET:
319  *
320  * Alg Part 1:
321  * 1. Start the PHY at Gen3 speed (default setting)
322  * 2. Issue the COMRESET
323  * 3. If no link, go to Alg Part 3
324  * 4. If link up, determine if the negotiated speed matches the PHY
325  *    configured speed
326  * 5. If they matched, go to Alg Part 2
327  * 6. If they do not matched and first time, configure the PHY for the linked
328  *    up disk speed and repeat step 2
329  * 7. Go to Alg Part 2
330  *
331  * Alg Part 2:
332  * 1. On link up, if there are any SERR_DISPARITY and SERR_10B_8B_ERR error
333  *    reported in the register PORT_SCR_ERR, then reset the PHY receiver line
334  * 2. Go to Alg Part 4
335  *
336  * Alg Part 3:
337  * 1. Check the PORT_SCR_STAT to see whether device presence detected but PHY
338  *    communication establishment failed and maximum link down attempts are
339  *    less than Max attempts 3 then goto Alg Part 1.
340  * 2. Go to Alg Part 4.
341  *
342  * Alg Part 4:
343  * 1. Clear any pending from register PORT_SCR_ERR.
344  *
345  * NOTE: For the initial version, we will NOT support Gen1/Gen2. In addition
346  *       and until the underlying PHY supports an method to reset the receiver
347  *       line, on detection of SERR_DISPARITY or SERR_10B_8B_ERR errors,
348  *       an warning message will be printed.
349  */
350 static int xgene_ahci_do_hardreset(struct ata_link *link,
351 				   unsigned long deadline, bool *online)
352 {
353 	const unsigned long *timing = sata_ehc_deb_timing(&link->eh_context);
354 	struct ata_port *ap = link->ap;
355 	struct ahci_host_priv *hpriv = ap->host->private_data;
356 	struct xgene_ahci_context *ctx = hpriv->plat_data;
357 	struct ahci_port_priv *pp = ap->private_data;
358 	u8 *d2h_fis = pp->rx_fis + RX_FIS_D2H_REG;
359 	void __iomem *port_mmio = ahci_port_base(ap);
360 	struct ata_taskfile tf;
361 	int link_down_retry = 0;
362 	int rc;
363 	u32 val, sstatus;
364 
365 	do {
366 		/* clear D2H reception area to properly wait for D2H FIS */
367 		ata_tf_init(link->device, &tf);
368 		tf.status = ATA_BUSY;
369 		ata_tf_to_fis(&tf, 0, 0, d2h_fis);
370 		rc = sata_link_hardreset(link, timing, deadline, online,
371 				 ahci_check_ready);
372 		if (*online) {
373 			val = readl(port_mmio + PORT_SCR_ERR);
374 			if (val & (SERR_DISPARITY | SERR_10B_8B_ERR))
375 				dev_warn(ctx->dev, "link has error\n");
376 			break;
377 		}
378 
379 		sata_scr_read(link, SCR_STATUS, &sstatus);
380 	} while (link_down_retry++ < MAX_LINK_DOWN_RETRY &&
381 		 (sstatus & 0xff) == 0x1);
382 
383 	/* clear all errors if any pending */
384 	val = readl(port_mmio + PORT_SCR_ERR);
385 	writel(val, port_mmio + PORT_SCR_ERR);
386 
387 	return rc;
388 }
389 
390 static int xgene_ahci_hardreset(struct ata_link *link, unsigned int *class,
391 				unsigned long deadline)
392 {
393 	struct ata_port *ap = link->ap;
394         struct ahci_host_priv *hpriv = ap->host->private_data;
395 	void __iomem *port_mmio = ahci_port_base(ap);
396 	bool online;
397 	int rc;
398 	u32 portcmd_saved;
399 	u32 portclb_saved;
400 	u32 portclbhi_saved;
401 	u32 portrxfis_saved;
402 	u32 portrxfishi_saved;
403 
404 	/* As hardreset resets these CSR, save it to restore later */
405 	portcmd_saved = readl(port_mmio + PORT_CMD);
406 	portclb_saved = readl(port_mmio + PORT_LST_ADDR);
407 	portclbhi_saved = readl(port_mmio + PORT_LST_ADDR_HI);
408 	portrxfis_saved = readl(port_mmio + PORT_FIS_ADDR);
409 	portrxfishi_saved = readl(port_mmio + PORT_FIS_ADDR_HI);
410 
411 	hpriv->stop_engine(ap);
412 
413 	rc = xgene_ahci_do_hardreset(link, deadline, &online);
414 
415 	/* As controller hardreset clears them, restore them */
416 	writel(portcmd_saved, port_mmio + PORT_CMD);
417 	writel(portclb_saved, port_mmio + PORT_LST_ADDR);
418 	writel(portclbhi_saved, port_mmio + PORT_LST_ADDR_HI);
419 	writel(portrxfis_saved, port_mmio + PORT_FIS_ADDR);
420 	writel(portrxfishi_saved, port_mmio + PORT_FIS_ADDR_HI);
421 
422 	hpriv->start_engine(ap);
423 
424 	if (online)
425 		*class = ahci_dev_classify(ap);
426 
427 	return rc;
428 }
429 
430 static void xgene_ahci_host_stop(struct ata_host *host)
431 {
432 	struct ahci_host_priv *hpriv = host->private_data;
433 
434 	ahci_platform_disable_resources(hpriv);
435 }
436 
437 /**
438  * xgene_ahci_pmp_softreset - Issue the softreset to the drives connected
439  *                            to Port Multiplier.
440  * @link: link to reset
441  * @class: Return value to indicate class of device
442  * @deadline: deadline jiffies for the operation
443  *
444  * Due to H/W errata, the controller is unable to save the PMP
445  * field fetched from command header before sending the H2D FIS.
446  * When the device returns the PMP port field in the D2H FIS, there is
447  * a mismatch and results in command completion failure. The workaround
448  * is to write the pmp value to PxFBS.DEV field before issuing any command
449  * to PMP.
450  */
451 static int xgene_ahci_pmp_softreset(struct ata_link *link, unsigned int *class,
452 			  unsigned long deadline)
453 {
454 	int pmp = sata_srst_pmp(link);
455 	struct ata_port *ap = link->ap;
456 	u32 rc;
457 	void __iomem *port_mmio = ahci_port_base(ap);
458 	u32 port_fbs;
459 
460 	/*
461 	 * Set PxFBS.DEV field with pmp
462 	 * value.
463 	 */
464 	port_fbs = readl(port_mmio + PORT_FBS);
465 	port_fbs &= ~PORT_FBS_DEV_MASK;
466 	port_fbs |= pmp << PORT_FBS_DEV_OFFSET;
467 	writel(port_fbs, port_mmio + PORT_FBS);
468 
469 	rc = ahci_do_softreset(link, class, pmp, deadline, ahci_check_ready);
470 
471 	return rc;
472 }
473 
474 /**
475  * xgene_ahci_softreset - Issue the softreset to the drive.
476  * @link: link to reset
477  * @class: Return value to indicate class of device
478  * @deadline: deadline jiffies for the operation
479  *
480  * Due to H/W errata, the controller is unable to save the PMP
481  * field fetched from command header before sending the H2D FIS.
482  * When the device returns the PMP port field in the D2H FIS, there is
483  * a mismatch and results in command completion failure. The workaround
484  * is to write the pmp value to PxFBS.DEV field before issuing any command
485  * to PMP. Here is the algorithm to detect PMP :
486  *
487  * 1. Save the PxFBS value
488  * 2. Program PxFBS.DEV with pmp value send by framework. Framework sends
489  *    0xF for both PMP/NON-PMP initially
490  * 3. Issue softreset
491  * 4. If signature class is PMP goto 6
492  * 5. restore the original PxFBS and goto 3
493  * 6. return
494  */
495 static int xgene_ahci_softreset(struct ata_link *link, unsigned int *class,
496 			  unsigned long deadline)
497 {
498 	int pmp = sata_srst_pmp(link);
499 	struct ata_port *ap = link->ap;
500 	struct ahci_host_priv *hpriv = ap->host->private_data;
501 	struct xgene_ahci_context *ctx = hpriv->plat_data;
502 	void __iomem *port_mmio = ahci_port_base(ap);
503 	u32 port_fbs;
504 	u32 port_fbs_save;
505 	u32 retry = 1;
506 	u32 rc;
507 
508 	port_fbs_save = readl(port_mmio + PORT_FBS);
509 
510 	/*
511 	 * Set PxFBS.DEV field with pmp
512 	 * value.
513 	 */
514 	port_fbs = readl(port_mmio + PORT_FBS);
515 	port_fbs &= ~PORT_FBS_DEV_MASK;
516 	port_fbs |= pmp << PORT_FBS_DEV_OFFSET;
517 	writel(port_fbs, port_mmio + PORT_FBS);
518 
519 softreset_retry:
520 	rc = ahci_do_softreset(link, class, pmp,
521 			       deadline, ahci_check_ready);
522 
523 	ctx->class[ap->port_no] = *class;
524 	if (*class != ATA_DEV_PMP) {
525 		/*
526 		 * Retry for normal drives without
527 		 * setting PxFBS.DEV field with pmp value.
528 		 */
529 		if (retry--) {
530 			writel(port_fbs_save, port_mmio + PORT_FBS);
531 			goto softreset_retry;
532 		}
533 	}
534 
535 	return rc;
536 }
537 
538 /**
539  * xgene_ahci_handle_broken_edge_irq - Handle the broken irq.
540  * @host: Host that recieved the irq
541  * @irq_masked: HOST_IRQ_STAT value
542  *
543  * For hardware with broken edge trigger latch
544  * the HOST_IRQ_STAT register misses the edge interrupt
545  * when clearing of HOST_IRQ_STAT register and hardware
546  * reporting the PORT_IRQ_STAT register at the
547  * same clock cycle.
548  * As such, the algorithm below outlines the workaround.
549  *
550  * 1. Read HOST_IRQ_STAT register and save the state.
551  * 2. Clear the HOST_IRQ_STAT register.
552  * 3. Read back the HOST_IRQ_STAT register.
553  * 4. If HOST_IRQ_STAT register equals to zero, then
554  *    traverse the rest of port's PORT_IRQ_STAT register
555  *    to check if an interrupt is triggered at that point else
556  *    go to step 6.
557  * 5. If PORT_IRQ_STAT register of rest ports is not equal to zero
558  *    then update the state of HOST_IRQ_STAT saved in step 1.
559  * 6. Handle port interrupts.
560  * 7. Exit
561  */
562 static int xgene_ahci_handle_broken_edge_irq(struct ata_host *host,
563 					     u32 irq_masked)
564 {
565 	struct ahci_host_priv *hpriv = host->private_data;
566 	void __iomem *port_mmio;
567 	int i;
568 
569 	if (!readl(hpriv->mmio + HOST_IRQ_STAT)) {
570 		for (i = 0; i < host->n_ports; i++) {
571 			if (irq_masked & (1 << i))
572 				continue;
573 
574 			port_mmio = ahci_port_base(host->ports[i]);
575 			if (readl(port_mmio + PORT_IRQ_STAT))
576 				irq_masked |= (1 << i);
577 		}
578 	}
579 
580 	return ahci_handle_port_intr(host, irq_masked);
581 }
582 
583 static irqreturn_t xgene_ahci_irq_intr(int irq, void *dev_instance)
584 {
585 	struct ata_host *host = dev_instance;
586 	struct ahci_host_priv *hpriv;
587 	unsigned int rc = 0;
588 	void __iomem *mmio;
589 	u32 irq_stat, irq_masked;
590 
591 	hpriv = host->private_data;
592 	mmio = hpriv->mmio;
593 
594 	/* sigh.  0xffffffff is a valid return from h/w */
595 	irq_stat = readl(mmio + HOST_IRQ_STAT);
596 	if (!irq_stat)
597 		return IRQ_NONE;
598 
599 	irq_masked = irq_stat & hpriv->port_map;
600 
601 	spin_lock(&host->lock);
602 
603 	/*
604 	 * HOST_IRQ_STAT behaves as edge triggered latch meaning that
605 	 * it should be cleared before all the port events are cleared.
606 	 */
607 	writel(irq_stat, mmio + HOST_IRQ_STAT);
608 
609 	rc = xgene_ahci_handle_broken_edge_irq(host, irq_masked);
610 
611 	spin_unlock(&host->lock);
612 
613 	return IRQ_RETVAL(rc);
614 }
615 
616 static struct ata_port_operations xgene_ahci_v1_ops = {
617 	.inherits = &ahci_ops,
618 	.host_stop = xgene_ahci_host_stop,
619 	.hardreset = xgene_ahci_hardreset,
620 	.read_id = xgene_ahci_read_id,
621 	.qc_issue = xgene_ahci_qc_issue,
622 	.softreset = xgene_ahci_softreset,
623 	.pmp_softreset = xgene_ahci_pmp_softreset
624 };
625 
626 static const struct ata_port_info xgene_ahci_v1_port_info = {
627 	.flags = AHCI_FLAG_COMMON | ATA_FLAG_PMP,
628 	.pio_mask = ATA_PIO4,
629 	.udma_mask = ATA_UDMA6,
630 	.port_ops = &xgene_ahci_v1_ops,
631 };
632 
633 static struct ata_port_operations xgene_ahci_v2_ops = {
634 	.inherits = &ahci_ops,
635 	.host_stop = xgene_ahci_host_stop,
636 	.hardreset = xgene_ahci_hardreset,
637 	.read_id = xgene_ahci_read_id,
638 };
639 
640 static const struct ata_port_info xgene_ahci_v2_port_info = {
641 	.flags = AHCI_FLAG_COMMON | ATA_FLAG_PMP,
642 	.pio_mask = ATA_PIO4,
643 	.udma_mask = ATA_UDMA6,
644 	.port_ops = &xgene_ahci_v2_ops,
645 };
646 
647 static int xgene_ahci_hw_init(struct ahci_host_priv *hpriv)
648 {
649 	struct xgene_ahci_context *ctx = hpriv->plat_data;
650 	int i;
651 	int rc;
652 	u32 val;
653 
654 	/* Remove IP RAM out of shutdown */
655 	rc = xgene_ahci_init_memram(ctx);
656 	if (rc)
657 		return rc;
658 
659 	for (i = 0; i < MAX_AHCI_CHN_PERCTR; i++)
660 		xgene_ahci_set_phy_cfg(ctx, i);
661 
662 	/* AXI disable Mask */
663 	writel(0xffffffff, hpriv->mmio + HOST_IRQ_STAT);
664 	readl(hpriv->mmio + HOST_IRQ_STAT); /* Force a barrier */
665 	writel(0, ctx->csr_core + INTSTATUSMASK);
666 	val = readl(ctx->csr_core + INTSTATUSMASK); /* Force a barrier */
667 	dev_dbg(ctx->dev, "top level interrupt mask 0x%X value 0x%08X\n",
668 		INTSTATUSMASK, val);
669 
670 	writel(0x0, ctx->csr_core + ERRINTSTATUSMASK);
671 	readl(ctx->csr_core + ERRINTSTATUSMASK); /* Force a barrier */
672 	writel(0x0, ctx->csr_axi + INT_SLV_TMOMASK);
673 	readl(ctx->csr_axi + INT_SLV_TMOMASK);
674 
675 	/* Enable AXI Interrupt */
676 	writel(0xffffffff, ctx->csr_core + SLVRDERRATTRIBUTES);
677 	writel(0xffffffff, ctx->csr_core + SLVWRERRATTRIBUTES);
678 	writel(0xffffffff, ctx->csr_core + MSTRDERRATTRIBUTES);
679 	writel(0xffffffff, ctx->csr_core + MSTWRERRATTRIBUTES);
680 
681 	/* Enable coherency */
682 	val = readl(ctx->csr_core + BUSCTLREG);
683 	val &= ~0x00000002;     /* Enable write coherency */
684 	val &= ~0x00000001;     /* Enable read coherency */
685 	writel(val, ctx->csr_core + BUSCTLREG);
686 
687 	val = readl(ctx->csr_core + IOFMSTRWAUX);
688 	val |= (1 << 3);        /* Enable read coherency */
689 	val |= (1 << 9);        /* Enable write coherency */
690 	writel(val, ctx->csr_core + IOFMSTRWAUX);
691 	val = readl(ctx->csr_core + IOFMSTRWAUX);
692 	dev_dbg(ctx->dev, "coherency 0x%X value 0x%08X\n",
693 		IOFMSTRWAUX, val);
694 
695 	return rc;
696 }
697 
698 static int xgene_ahci_mux_select(struct xgene_ahci_context *ctx)
699 {
700 	u32 val;
701 
702 	/* Check for optional MUX resource */
703 	if (!ctx->csr_mux)
704 		return 0;
705 
706 	val = readl(ctx->csr_mux + SATA_ENET_CONFIG_REG);
707 	val &= ~CFG_SATA_ENET_SELECT_MASK;
708 	writel(val, ctx->csr_mux + SATA_ENET_CONFIG_REG);
709 	val = readl(ctx->csr_mux + SATA_ENET_CONFIG_REG);
710 	return val & CFG_SATA_ENET_SELECT_MASK ? -1 : 0;
711 }
712 
713 static const struct scsi_host_template ahci_platform_sht = {
714 	AHCI_SHT(DRV_NAME),
715 };
716 
717 #ifdef CONFIG_ACPI
718 static const struct acpi_device_id xgene_ahci_acpi_match[] = {
719 	{ "APMC0D0D", XGENE_AHCI_V1},
720 	{ "APMC0D32", XGENE_AHCI_V2},
721 	{},
722 };
723 MODULE_DEVICE_TABLE(acpi, xgene_ahci_acpi_match);
724 #endif
725 
726 static const struct of_device_id xgene_ahci_of_match[] = {
727 	{.compatible = "apm,xgene-ahci", .data = (void *) XGENE_AHCI_V1},
728 	{.compatible = "apm,xgene-ahci-v2", .data = (void *) XGENE_AHCI_V2},
729 	{ /* sentinel */ }
730 };
731 MODULE_DEVICE_TABLE(of, xgene_ahci_of_match);
732 
733 static int xgene_ahci_probe(struct platform_device *pdev)
734 {
735 	struct device *dev = &pdev->dev;
736 	struct ahci_host_priv *hpriv;
737 	struct xgene_ahci_context *ctx;
738 	struct resource *res;
739 	const struct of_device_id *of_devid;
740 	enum xgene_ahci_version version = XGENE_AHCI_V1;
741 	const struct ata_port_info *ppi[] = { &xgene_ahci_v1_port_info,
742 					      &xgene_ahci_v2_port_info };
743 	int rc;
744 
745 	hpriv = ahci_platform_get_resources(pdev, 0);
746 	if (IS_ERR(hpriv))
747 		return PTR_ERR(hpriv);
748 
749 	ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
750 	if (!ctx)
751 		return -ENOMEM;
752 
753 	hpriv->plat_data = ctx;
754 	ctx->hpriv = hpriv;
755 	ctx->dev = dev;
756 
757 	/* Retrieve the IP core resource */
758 	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
759 	ctx->csr_core = devm_ioremap_resource(dev, res);
760 	if (IS_ERR(ctx->csr_core))
761 		return PTR_ERR(ctx->csr_core);
762 
763 	/* Retrieve the IP diagnostic resource */
764 	res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
765 	ctx->csr_diag = devm_ioremap_resource(dev, res);
766 	if (IS_ERR(ctx->csr_diag))
767 		return PTR_ERR(ctx->csr_diag);
768 
769 	/* Retrieve the IP AXI resource */
770 	res = platform_get_resource(pdev, IORESOURCE_MEM, 3);
771 	ctx->csr_axi = devm_ioremap_resource(dev, res);
772 	if (IS_ERR(ctx->csr_axi))
773 		return PTR_ERR(ctx->csr_axi);
774 
775 	/* Retrieve the optional IP mux resource */
776 	res = platform_get_resource(pdev, IORESOURCE_MEM, 4);
777 	if (res) {
778 		void __iomem *csr = devm_ioremap_resource(dev, res);
779 		if (IS_ERR(csr))
780 			return PTR_ERR(csr);
781 
782 		ctx->csr_mux = csr;
783 	}
784 
785 	of_devid = of_match_device(xgene_ahci_of_match, dev);
786 	if (of_devid) {
787 		if (of_devid->data)
788 			version = (unsigned long) of_devid->data;
789 	}
790 #ifdef CONFIG_ACPI
791 	else {
792 		const struct acpi_device_id *acpi_id;
793 		struct acpi_device_info *info;
794 		acpi_status status;
795 
796 		acpi_id = acpi_match_device(xgene_ahci_acpi_match, &pdev->dev);
797 		if (!acpi_id) {
798 			dev_warn(&pdev->dev, "No node entry in ACPI table. Assume version1\n");
799 			version = XGENE_AHCI_V1;
800 		} else if (acpi_id->driver_data) {
801 			version = (enum xgene_ahci_version) acpi_id->driver_data;
802 			status = acpi_get_object_info(ACPI_HANDLE(&pdev->dev), &info);
803 			if (ACPI_FAILURE(status)) {
804 				dev_warn(&pdev->dev, "%s: Error reading device info. Assume version1\n",
805 					__func__);
806 				version = XGENE_AHCI_V1;
807 			} else {
808 				if (info->valid & ACPI_VALID_CID)
809 					version = XGENE_AHCI_V2;
810 				kfree(info);
811 			}
812 		}
813 	}
814 #endif
815 
816 	dev_dbg(dev, "VAddr 0x%p Mmio VAddr 0x%p\n", ctx->csr_core,
817 		hpriv->mmio);
818 
819 	/* Select ATA */
820 	if ((rc = xgene_ahci_mux_select(ctx))) {
821 		dev_err(dev, "SATA mux selection failed error %d\n", rc);
822 		return -ENODEV;
823 	}
824 
825 	if (xgene_ahci_is_memram_inited(ctx)) {
826 		dev_info(dev, "skip clock and PHY initialization\n");
827 		goto skip_clk_phy;
828 	}
829 
830 	/* Due to errata, HW requires full toggle transition */
831 	rc = ahci_platform_enable_clks(hpriv);
832 	if (rc)
833 		goto disable_resources;
834 	ahci_platform_disable_clks(hpriv);
835 
836 	rc = ahci_platform_enable_resources(hpriv);
837 	if (rc)
838 		goto disable_resources;
839 
840 	/* Configure the host controller */
841 	xgene_ahci_hw_init(hpriv);
842 skip_clk_phy:
843 
844 	switch (version) {
845 	case XGENE_AHCI_V1:
846 		hpriv->flags = AHCI_HFLAG_NO_NCQ;
847 		break;
848 	case XGENE_AHCI_V2:
849 		hpriv->flags |= AHCI_HFLAG_YES_FBS;
850 		hpriv->irq_handler = xgene_ahci_irq_intr;
851 		break;
852 	default:
853 		break;
854 	}
855 
856 	rc = ahci_platform_init_host(pdev, hpriv, ppi[version - 1],
857 				     &ahci_platform_sht);
858 	if (rc)
859 		goto disable_resources;
860 
861 	dev_dbg(dev, "X-Gene SATA host controller initialized\n");
862 	return 0;
863 
864 disable_resources:
865 	ahci_platform_disable_resources(hpriv);
866 	return rc;
867 }
868 
869 static struct platform_driver xgene_ahci_driver = {
870 	.probe = xgene_ahci_probe,
871 	.remove_new = ata_platform_remove_one,
872 	.driver = {
873 		.name = DRV_NAME,
874 		.of_match_table = xgene_ahci_of_match,
875 		.acpi_match_table = ACPI_PTR(xgene_ahci_acpi_match),
876 	},
877 };
878 
879 module_platform_driver(xgene_ahci_driver);
880 
881 MODULE_DESCRIPTION("APM X-Gene AHCI SATA driver");
882 MODULE_AUTHOR("Loc Ho <lho@apm.com>");
883 MODULE_LICENSE("GPL");
884 MODULE_VERSION("0.4");
885