xref: /openbmc/linux/drivers/ata/ahci_xgene.c (revision 62e7ca52)
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 /* Max # of disk per a controller */
34 #define MAX_AHCI_CHN_PERCTR		2
35 
36 /* MUX CSR */
37 #define SATA_ENET_CONFIG_REG		0x00000000
38 #define  CFG_SATA_ENET_SELECT_MASK	0x00000001
39 
40 /* SATA core host controller CSR */
41 #define SLVRDERRATTRIBUTES		0x00000000
42 #define SLVWRERRATTRIBUTES		0x00000004
43 #define MSTRDERRATTRIBUTES		0x00000008
44 #define MSTWRERRATTRIBUTES		0x0000000c
45 #define BUSCTLREG			0x00000014
46 #define IOFMSTRWAUX			0x00000018
47 #define INTSTATUSMASK			0x0000002c
48 #define ERRINTSTATUS			0x00000030
49 #define ERRINTSTATUSMASK		0x00000034
50 
51 /* SATA host AHCI CSR */
52 #define PORTCFG				0x000000a4
53 #define  PORTADDR_SET(dst, src) \
54 		(((dst) & ~0x0000003f) | (((u32)(src)) & 0x0000003f))
55 #define PORTPHY1CFG		0x000000a8
56 #define PORTPHY1CFG_FRCPHYRDY_SET(dst, src) \
57 		(((dst) & ~0x00100000) | (((u32)(src) << 0x14) & 0x00100000))
58 #define PORTPHY2CFG			0x000000ac
59 #define PORTPHY3CFG			0x000000b0
60 #define PORTPHY4CFG			0x000000b4
61 #define PORTPHY5CFG			0x000000b8
62 #define SCTL0				0x0000012C
63 #define PORTPHY5CFG_RTCHG_SET(dst, src) \
64 		(((dst) & ~0xfff00000) | (((u32)(src) << 0x14) & 0xfff00000))
65 #define PORTAXICFG_EN_CONTEXT_SET(dst, src) \
66 		(((dst) & ~0x01000000) | (((u32)(src) << 0x18) & 0x01000000))
67 #define PORTAXICFG			0x000000bc
68 #define PORTAXICFG_OUTTRANS_SET(dst, src) \
69 		(((dst) & ~0x00f00000) | (((u32)(src) << 0x14) & 0x00f00000))
70 #define PORTRANSCFG			0x000000c8
71 #define PORTRANSCFG_RXWM_SET(dst, src)		\
72 		(((dst) & ~0x0000007f) | (((u32)(src)) & 0x0000007f))
73 
74 /* SATA host controller AXI CSR */
75 #define INT_SLV_TMOMASK			0x00000010
76 
77 /* SATA diagnostic CSR */
78 #define CFG_MEM_RAM_SHUTDOWN		0x00000070
79 #define BLOCK_MEM_RDY			0x00000074
80 
81 struct xgene_ahci_context {
82 	struct ahci_host_priv *hpriv;
83 	struct device *dev;
84 	u8 last_cmd[MAX_AHCI_CHN_PERCTR]; /* tracking the last command issued*/
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_restart_engine - Restart the dma engine.
106  * @ap : ATA port of interest
107  *
108  * Restarts the dma engine inside the controller.
109  */
110 static int xgene_ahci_restart_engine(struct ata_port *ap)
111 {
112 	struct ahci_host_priv *hpriv = ap->host->private_data;
113 
114 	ahci_stop_engine(ap);
115 	ahci_start_fis_rx(ap);
116 	hpriv->start_engine(ap);
117 
118 	return 0;
119 }
120 
121 /**
122  * xgene_ahci_qc_issue - Issue commands to the device
123  * @qc: Command to issue
124  *
125  * Due to Hardware errata for IDENTIFY DEVICE command, the controller cannot
126  * clear the BSY bit after receiving the PIO setup FIS. This results in the dma
127  * state machine goes into the CMFatalErrorUpdate state and locks up. By
128  * restarting the dma engine, it removes the controller out of lock up state.
129  */
130 static unsigned int xgene_ahci_qc_issue(struct ata_queued_cmd *qc)
131 {
132 	struct ata_port *ap = qc->ap;
133 	struct ahci_host_priv *hpriv = ap->host->private_data;
134 	struct xgene_ahci_context *ctx = hpriv->plat_data;
135 	int rc = 0;
136 
137 	if (unlikely(ctx->last_cmd[ap->port_no] == ATA_CMD_ID_ATA))
138 		xgene_ahci_restart_engine(ap);
139 
140 	rc = ahci_qc_issue(qc);
141 
142 	/* Save the last command issued */
143 	ctx->last_cmd[ap->port_no] = qc->tf.command;
144 
145 	return rc;
146 }
147 
148 /**
149  * xgene_ahci_read_id - Read ID data from the specified device
150  * @dev: device
151  * @tf: proposed taskfile
152  * @id: data buffer
153  *
154  * This custom read ID function is required due to the fact that the HW
155  * does not support DEVSLP.
156  */
157 static unsigned int xgene_ahci_read_id(struct ata_device *dev,
158 				       struct ata_taskfile *tf, u16 *id)
159 {
160 	u32 err_mask;
161 
162 	err_mask = ata_do_dev_read_id(dev, tf, id);
163 	if (err_mask)
164 		return err_mask;
165 
166 	/*
167 	 * Mask reserved area. Word78 spec of Link Power Management
168 	 * bit15-8: reserved
169 	 * bit7: NCQ autosence
170 	 * bit6: Software settings preservation supported
171 	 * bit5: reserved
172 	 * bit4: In-order sata delivery supported
173 	 * bit3: DIPM requests supported
174 	 * bit2: DMA Setup FIS Auto-Activate optimization supported
175 	 * bit1: DMA Setup FIX non-Zero buffer offsets supported
176 	 * bit0: Reserved
177 	 *
178 	 * Clear reserved bit 8 (DEVSLP bit) as we don't support DEVSLP
179 	 */
180 	id[ATA_ID_FEATURE_SUPP] &= ~(1 << 8);
181 
182 	return 0;
183 }
184 
185 static void xgene_ahci_set_phy_cfg(struct xgene_ahci_context *ctx, int channel)
186 {
187 	void __iomem *mmio = ctx->hpriv->mmio;
188 	u32 val;
189 
190 	dev_dbg(ctx->dev, "port configure mmio 0x%p channel %d\n",
191 		mmio, channel);
192 	val = readl(mmio + PORTCFG);
193 	val = PORTADDR_SET(val, channel == 0 ? 2 : 3);
194 	writel(val, mmio + PORTCFG);
195 	readl(mmio + PORTCFG);  /* Force a barrier */
196 	/* Disable fix rate */
197 	writel(0x0001fffe, mmio + PORTPHY1CFG);
198 	readl(mmio + PORTPHY1CFG); /* Force a barrier */
199 	writel(0x28183219, mmio + PORTPHY2CFG);
200 	readl(mmio + PORTPHY2CFG); /* Force a barrier */
201 	writel(0x13081008, mmio + PORTPHY3CFG);
202 	readl(mmio + PORTPHY3CFG); /* Force a barrier */
203 	writel(0x00480815, mmio + PORTPHY4CFG);
204 	readl(mmio + PORTPHY4CFG); /* Force a barrier */
205 	/* Set window negotiation */
206 	val = readl(mmio + PORTPHY5CFG);
207 	val = PORTPHY5CFG_RTCHG_SET(val, 0x300);
208 	writel(val, mmio + PORTPHY5CFG);
209 	readl(mmio + PORTPHY5CFG); /* Force a barrier */
210 	val = readl(mmio + PORTAXICFG);
211 	val = PORTAXICFG_EN_CONTEXT_SET(val, 0x1); /* Enable context mgmt */
212 	val = PORTAXICFG_OUTTRANS_SET(val, 0xe); /* Set outstanding */
213 	writel(val, mmio + PORTAXICFG);
214 	readl(mmio + PORTAXICFG); /* Force a barrier */
215 	/* Set the watermark threshold of the receive FIFO */
216 	val = readl(mmio + PORTRANSCFG);
217 	val = PORTRANSCFG_RXWM_SET(val, 0x30);
218 	writel(val, mmio + PORTRANSCFG);
219 }
220 
221 /**
222  * xgene_ahci_do_hardreset - Issue the actual COMRESET
223  * @link: link to reset
224  * @deadline: deadline jiffies for the operation
225  * @online: Return value to indicate if device online
226  *
227  * Due to the limitation of the hardware PHY, a difference set of setting is
228  * required for each supported disk speed - Gen3 (6.0Gbps), Gen2 (3.0Gbps),
229  * and Gen1 (1.5Gbps). Otherwise during long IO stress test, the PHY will
230  * report disparity error and etc. In addition, during COMRESET, there can
231  * be error reported in the register PORT_SCR_ERR. For SERR_DISPARITY and
232  * SERR_10B_8B_ERR, the PHY receiver line must be reseted. The following
233  * algorithm is followed to proper configure the hardware PHY during COMRESET:
234  *
235  * Alg Part 1:
236  * 1. Start the PHY at Gen3 speed (default setting)
237  * 2. Issue the COMRESET
238  * 3. If no link, go to Alg Part 3
239  * 4. If link up, determine if the negotiated speed matches the PHY
240  *    configured speed
241  * 5. If they matched, go to Alg Part 2
242  * 6. If they do not matched and first time, configure the PHY for the linked
243  *    up disk speed and repeat step 2
244  * 7. Go to Alg Part 2
245  *
246  * Alg Part 2:
247  * 1. On link up, if there are any SERR_DISPARITY and SERR_10B_8B_ERR error
248  *    reported in the register PORT_SCR_ERR, then reset the PHY receiver line
249  * 2. Go to Alg Part 3
250  *
251  * Alg Part 3:
252  * 1. Clear any pending from register PORT_SCR_ERR.
253  *
254  * NOTE: For the initial version, we will NOT support Gen1/Gen2. In addition
255  *       and until the underlying PHY supports an method to reset the receiver
256  *       line, on detection of SERR_DISPARITY or SERR_10B_8B_ERR errors,
257  *       an warning message will be printed.
258  */
259 static int xgene_ahci_do_hardreset(struct ata_link *link,
260 				   unsigned long deadline, bool *online)
261 {
262 	const unsigned long *timing = sata_ehc_deb_timing(&link->eh_context);
263 	struct ata_port *ap = link->ap;
264 	struct ahci_host_priv *hpriv = ap->host->private_data;
265 	struct xgene_ahci_context *ctx = hpriv->plat_data;
266 	struct ahci_port_priv *pp = ap->private_data;
267 	u8 *d2h_fis = pp->rx_fis + RX_FIS_D2H_REG;
268 	void __iomem *port_mmio = ahci_port_base(ap);
269 	struct ata_taskfile tf;
270 	int rc;
271 	u32 val;
272 
273 	/* clear D2H reception area to properly wait for D2H FIS */
274 	ata_tf_init(link->device, &tf);
275 	tf.command = ATA_BUSY;
276 	ata_tf_to_fis(&tf, 0, 0, d2h_fis);
277 	rc = sata_link_hardreset(link, timing, deadline, online,
278 				 ahci_check_ready);
279 
280 	val = readl(port_mmio + PORT_SCR_ERR);
281 	if (val & (SERR_DISPARITY | SERR_10B_8B_ERR))
282 		dev_warn(ctx->dev, "link has error\n");
283 
284 	/* clear all errors if any pending */
285 	val = readl(port_mmio + PORT_SCR_ERR);
286 	writel(val, port_mmio + PORT_SCR_ERR);
287 
288 	return rc;
289 }
290 
291 static int xgene_ahci_hardreset(struct ata_link *link, unsigned int *class,
292 				unsigned long deadline)
293 {
294 	struct ata_port *ap = link->ap;
295         struct ahci_host_priv *hpriv = ap->host->private_data;
296 	void __iomem *port_mmio = ahci_port_base(ap);
297 	bool online;
298 	int rc;
299 	u32 portcmd_saved;
300 	u32 portclb_saved;
301 	u32 portclbhi_saved;
302 	u32 portrxfis_saved;
303 	u32 portrxfishi_saved;
304 
305 	/* As hardreset resets these CSR, save it to restore later */
306 	portcmd_saved = readl(port_mmio + PORT_CMD);
307 	portclb_saved = readl(port_mmio + PORT_LST_ADDR);
308 	portclbhi_saved = readl(port_mmio + PORT_LST_ADDR_HI);
309 	portrxfis_saved = readl(port_mmio + PORT_FIS_ADDR);
310 	portrxfishi_saved = readl(port_mmio + PORT_FIS_ADDR_HI);
311 
312 	ahci_stop_engine(ap);
313 
314 	rc = xgene_ahci_do_hardreset(link, deadline, &online);
315 
316 	/* As controller hardreset clears them, restore them */
317 	writel(portcmd_saved, port_mmio + PORT_CMD);
318 	writel(portclb_saved, port_mmio + PORT_LST_ADDR);
319 	writel(portclbhi_saved, port_mmio + PORT_LST_ADDR_HI);
320 	writel(portrxfis_saved, port_mmio + PORT_FIS_ADDR);
321 	writel(portrxfishi_saved, port_mmio + PORT_FIS_ADDR_HI);
322 
323 	hpriv->start_engine(ap);
324 
325 	if (online)
326 		*class = ahci_dev_classify(ap);
327 
328 	return rc;
329 }
330 
331 static void xgene_ahci_host_stop(struct ata_host *host)
332 {
333 	struct ahci_host_priv *hpriv = host->private_data;
334 
335 	ahci_platform_disable_resources(hpriv);
336 }
337 
338 static struct ata_port_operations xgene_ahci_ops = {
339 	.inherits = &ahci_ops,
340 	.host_stop = xgene_ahci_host_stop,
341 	.hardreset = xgene_ahci_hardreset,
342 	.read_id = xgene_ahci_read_id,
343 	.qc_issue = xgene_ahci_qc_issue,
344 };
345 
346 static const struct ata_port_info xgene_ahci_port_info = {
347 	.flags = AHCI_FLAG_COMMON | ATA_FLAG_NCQ,
348 	.pio_mask = ATA_PIO4,
349 	.udma_mask = ATA_UDMA6,
350 	.port_ops = &xgene_ahci_ops,
351 };
352 
353 static int xgene_ahci_hw_init(struct ahci_host_priv *hpriv)
354 {
355 	struct xgene_ahci_context *ctx = hpriv->plat_data;
356 	int i;
357 	int rc;
358 	u32 val;
359 
360 	/* Remove IP RAM out of shutdown */
361 	rc = xgene_ahci_init_memram(ctx);
362 	if (rc)
363 		return rc;
364 
365 	for (i = 0; i < MAX_AHCI_CHN_PERCTR; i++)
366 		xgene_ahci_set_phy_cfg(ctx, i);
367 
368 	/* AXI disable Mask */
369 	writel(0xffffffff, hpriv->mmio + HOST_IRQ_STAT);
370 	readl(hpriv->mmio + HOST_IRQ_STAT); /* Force a barrier */
371 	writel(0, ctx->csr_core + INTSTATUSMASK);
372 	val = readl(ctx->csr_core + INTSTATUSMASK); /* Force a barrier */
373 	dev_dbg(ctx->dev, "top level interrupt mask 0x%X value 0x%08X\n",
374 		INTSTATUSMASK, val);
375 
376 	writel(0x0, ctx->csr_core + ERRINTSTATUSMASK);
377 	readl(ctx->csr_core + ERRINTSTATUSMASK); /* Force a barrier */
378 	writel(0x0, ctx->csr_axi + INT_SLV_TMOMASK);
379 	readl(ctx->csr_axi + INT_SLV_TMOMASK);
380 
381 	/* Enable AXI Interrupt */
382 	writel(0xffffffff, ctx->csr_core + SLVRDERRATTRIBUTES);
383 	writel(0xffffffff, ctx->csr_core + SLVWRERRATTRIBUTES);
384 	writel(0xffffffff, ctx->csr_core + MSTRDERRATTRIBUTES);
385 	writel(0xffffffff, ctx->csr_core + MSTWRERRATTRIBUTES);
386 
387 	/* Enable coherency */
388 	val = readl(ctx->csr_core + BUSCTLREG);
389 	val &= ~0x00000002;     /* Enable write coherency */
390 	val &= ~0x00000001;     /* Enable read coherency */
391 	writel(val, ctx->csr_core + BUSCTLREG);
392 
393 	val = readl(ctx->csr_core + IOFMSTRWAUX);
394 	val |= (1 << 3);        /* Enable read coherency */
395 	val |= (1 << 9);        /* Enable write coherency */
396 	writel(val, ctx->csr_core + IOFMSTRWAUX);
397 	val = readl(ctx->csr_core + IOFMSTRWAUX);
398 	dev_dbg(ctx->dev, "coherency 0x%X value 0x%08X\n",
399 		IOFMSTRWAUX, val);
400 
401 	return rc;
402 }
403 
404 static int xgene_ahci_mux_select(struct xgene_ahci_context *ctx)
405 {
406 	u32 val;
407 
408 	/* Check for optional MUX resource */
409 	if (IS_ERR(ctx->csr_mux))
410 		return 0;
411 
412 	val = readl(ctx->csr_mux + SATA_ENET_CONFIG_REG);
413 	val &= ~CFG_SATA_ENET_SELECT_MASK;
414 	writel(val, ctx->csr_mux + SATA_ENET_CONFIG_REG);
415 	val = readl(ctx->csr_mux + SATA_ENET_CONFIG_REG);
416 	return val & CFG_SATA_ENET_SELECT_MASK ? -1 : 0;
417 }
418 
419 static int xgene_ahci_probe(struct platform_device *pdev)
420 {
421 	struct device *dev = &pdev->dev;
422 	struct ahci_host_priv *hpriv;
423 	struct xgene_ahci_context *ctx;
424 	struct resource *res;
425 	int rc;
426 
427 	hpriv = ahci_platform_get_resources(pdev);
428 	if (IS_ERR(hpriv))
429 		return PTR_ERR(hpriv);
430 
431 	ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
432 	if (!ctx)
433 		return -ENOMEM;
434 
435 	hpriv->plat_data = ctx;
436 	ctx->hpriv = hpriv;
437 	ctx->dev = dev;
438 
439 	/* Retrieve the IP core resource */
440 	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
441 	ctx->csr_core = devm_ioremap_resource(dev, res);
442 	if (IS_ERR(ctx->csr_core))
443 		return PTR_ERR(ctx->csr_core);
444 
445 	/* Retrieve the IP diagnostic resource */
446 	res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
447 	ctx->csr_diag = devm_ioremap_resource(dev, res);
448 	if (IS_ERR(ctx->csr_diag))
449 		return PTR_ERR(ctx->csr_diag);
450 
451 	/* Retrieve the IP AXI resource */
452 	res = platform_get_resource(pdev, IORESOURCE_MEM, 3);
453 	ctx->csr_axi = devm_ioremap_resource(dev, res);
454 	if (IS_ERR(ctx->csr_axi))
455 		return PTR_ERR(ctx->csr_axi);
456 
457 	/* Retrieve the optional IP mux resource */
458 	res = platform_get_resource(pdev, IORESOURCE_MEM, 4);
459 	ctx->csr_mux = devm_ioremap_resource(dev, res);
460 
461 	dev_dbg(dev, "VAddr 0x%p Mmio VAddr 0x%p\n", ctx->csr_core,
462 		hpriv->mmio);
463 
464 	/* Select ATA */
465 	if ((rc = xgene_ahci_mux_select(ctx))) {
466 		dev_err(dev, "SATA mux selection failed error %d\n", rc);
467 		return -ENODEV;
468 	}
469 
470 	/* Due to errata, HW requires full toggle transition */
471 	rc = ahci_platform_enable_clks(hpriv);
472 	if (rc)
473 		goto disable_resources;
474 	ahci_platform_disable_clks(hpriv);
475 
476 	rc = ahci_platform_enable_resources(hpriv);
477 	if (rc)
478 		goto disable_resources;
479 
480 	/* Configure the host controller */
481 	xgene_ahci_hw_init(hpriv);
482 
483 	hpriv->flags = AHCI_HFLAG_NO_PMP | AHCI_HFLAG_YES_NCQ;
484 
485 	rc = ahci_platform_init_host(pdev, hpriv, &xgene_ahci_port_info);
486 	if (rc)
487 		goto disable_resources;
488 
489 	dev_dbg(dev, "X-Gene SATA host controller initialized\n");
490 	return 0;
491 
492 disable_resources:
493 	ahci_platform_disable_resources(hpriv);
494 	return rc;
495 }
496 
497 static const struct of_device_id xgene_ahci_of_match[] = {
498 	{.compatible = "apm,xgene-ahci"},
499 	{},
500 };
501 MODULE_DEVICE_TABLE(of, xgene_ahci_of_match);
502 
503 static struct platform_driver xgene_ahci_driver = {
504 	.probe = xgene_ahci_probe,
505 	.remove = ata_platform_remove_one,
506 	.driver = {
507 		.name = "xgene-ahci",
508 		.owner = THIS_MODULE,
509 		.of_match_table = xgene_ahci_of_match,
510 	},
511 };
512 
513 module_platform_driver(xgene_ahci_driver);
514 
515 MODULE_DESCRIPTION("APM X-Gene AHCI SATA driver");
516 MODULE_AUTHOR("Loc Ho <lho@apm.com>");
517 MODULE_LICENSE("GPL");
518 MODULE_VERSION("0.4");
519