1 // SPDX-License-Identifier: GPL-2.0
2 
3 /*
4  * Palmchip BK3710 PATA controller driver
5  *
6  * Copyright (c) 2017 Samsung Electronics Co., Ltd.
7  *		http://www.samsung.com
8  *
9  * Based on palm_bk3710.c:
10  *
11  * Copyright (C) 2006 Texas Instruments.
12  * Copyright (C) 2007 MontaVista Software, Inc., <source@mvista.com>
13  */
14 
15 #include <linux/ata.h>
16 #include <linux/clk.h>
17 #include <linux/delay.h>
18 #include <linux/init.h>
19 #include <linux/ioport.h>
20 #include <linux/kernel.h>
21 #include <linux/libata.h>
22 #include <linux/module.h>
23 #include <linux/platform_device.h>
24 #include <linux/types.h>
25 
26 #define DRV_NAME "pata_bk3710"
27 
28 #define BK3710_TF_OFFSET	0x1F0
29 #define BK3710_CTL_OFFSET	0x3F6
30 
31 #define BK3710_BMISP		0x02
32 #define BK3710_IDETIMP		0x40
33 #define BK3710_UDMACTL		0x48
34 #define BK3710_MISCCTL		0x50
35 #define BK3710_REGSTB		0x54
36 #define BK3710_REGRCVR		0x58
37 #define BK3710_DATSTB		0x5C
38 #define BK3710_DATRCVR		0x60
39 #define BK3710_DMASTB		0x64
40 #define BK3710_DMARCVR		0x68
41 #define BK3710_UDMASTB		0x6C
42 #define BK3710_UDMATRP		0x70
43 #define BK3710_UDMAENV		0x74
44 #define BK3710_IORDYTMP		0x78
45 
46 static struct scsi_host_template pata_bk3710_sht = {
47 	ATA_BMDMA_SHT(DRV_NAME),
48 };
49 
50 static unsigned int ideclk_period; /* in nanoseconds */
51 
52 struct pata_bk3710_udmatiming {
53 	unsigned int rptime;	/* tRP -- Ready to pause time (nsec) */
54 	unsigned int cycletime;	/* tCYCTYP2/2 -- avg Cycle Time (nsec) */
55 				/* tENV is always a minimum of 20 nsec */
56 };
57 
58 static const struct pata_bk3710_udmatiming pata_bk3710_udmatimings[6] = {
59 	{ 160, 240 / 2 },	/* UDMA Mode 0 */
60 	{ 125, 160 / 2 },	/* UDMA Mode 1 */
61 	{ 100, 120 / 2 },	/* UDMA Mode 2 */
62 	{ 100,  90 / 2 },	/* UDMA Mode 3 */
63 	{ 100,  60 / 2 },	/* UDMA Mode 4 */
64 	{  85,  40 / 2 },	/* UDMA Mode 5 */
65 };
66 
pata_bk3710_setudmamode(void __iomem * base,unsigned int dev,unsigned int mode)67 static void pata_bk3710_setudmamode(void __iomem *base, unsigned int dev,
68 				    unsigned int mode)
69 {
70 	u32 val32;
71 	u16 val16;
72 	u8 tenv, trp, t0;
73 
74 	/* DMA Data Setup */
75 	t0 = DIV_ROUND_UP(pata_bk3710_udmatimings[mode].cycletime,
76 			  ideclk_period) - 1;
77 	tenv = DIV_ROUND_UP(20, ideclk_period) - 1;
78 	trp = DIV_ROUND_UP(pata_bk3710_udmatimings[mode].rptime,
79 			   ideclk_period) - 1;
80 
81 	/* udmastb Ultra DMA Access Strobe Width */
82 	val32 = ioread32(base + BK3710_UDMASTB) & (0xFF << (dev ? 0 : 8));
83 	val32 |= t0 << (dev ? 8 : 0);
84 	iowrite32(val32, base + BK3710_UDMASTB);
85 
86 	/* udmatrp Ultra DMA Ready to Pause Time */
87 	val32 = ioread32(base + BK3710_UDMATRP) & (0xFF << (dev ? 0 : 8));
88 	val32 |= trp << (dev ? 8 : 0);
89 	iowrite32(val32, base + BK3710_UDMATRP);
90 
91 	/* udmaenv Ultra DMA envelop Time */
92 	val32 = ioread32(base + BK3710_UDMAENV) & (0xFF << (dev ? 0 : 8));
93 	val32 |= tenv << (dev ? 8 : 0);
94 	iowrite32(val32, base + BK3710_UDMAENV);
95 
96 	/* Enable UDMA for Device */
97 	val16 = ioread16(base + BK3710_UDMACTL) | (1 << dev);
98 	iowrite16(val16, base + BK3710_UDMACTL);
99 }
100 
pata_bk3710_setmwdmamode(void __iomem * base,unsigned int dev,unsigned short min_cycle,unsigned int mode)101 static void pata_bk3710_setmwdmamode(void __iomem *base, unsigned int dev,
102 				     unsigned short min_cycle,
103 				     unsigned int mode)
104 {
105 	const struct ata_timing *t;
106 	int cycletime;
107 	u32 val32;
108 	u16 val16;
109 	u8 td, tkw, t0;
110 
111 	t = ata_timing_find_mode(mode);
112 	cycletime = max_t(int, t->cycle, min_cycle);
113 
114 	/* DMA Data Setup */
115 	t0 = DIV_ROUND_UP(cycletime, ideclk_period);
116 	td = DIV_ROUND_UP(t->active, ideclk_period);
117 	tkw = t0 - td - 1;
118 	td--;
119 
120 	val32 = ioread32(base + BK3710_DMASTB) & (0xFF << (dev ? 0 : 8));
121 	val32 |= td << (dev ? 8 : 0);
122 	iowrite32(val32, base + BK3710_DMASTB);
123 
124 	val32 = ioread32(base + BK3710_DMARCVR) & (0xFF << (dev ? 0 : 8));
125 	val32 |= tkw << (dev ? 8 : 0);
126 	iowrite32(val32, base + BK3710_DMARCVR);
127 
128 	/* Disable UDMA for Device */
129 	val16 = ioread16(base + BK3710_UDMACTL) & ~(1 << dev);
130 	iowrite16(val16, base + BK3710_UDMACTL);
131 }
132 
pata_bk3710_set_dmamode(struct ata_port * ap,struct ata_device * adev)133 static void pata_bk3710_set_dmamode(struct ata_port *ap,
134 				    struct ata_device *adev)
135 {
136 	void __iomem *base = (void __iomem *)ap->ioaddr.bmdma_addr;
137 	int is_slave = adev->devno;
138 	const u8 xferspeed = adev->dma_mode;
139 
140 	if (xferspeed >= XFER_UDMA_0)
141 		pata_bk3710_setudmamode(base, is_slave,
142 					xferspeed - XFER_UDMA_0);
143 	else
144 		pata_bk3710_setmwdmamode(base, is_slave,
145 					 adev->id[ATA_ID_EIDE_DMA_MIN],
146 					 xferspeed);
147 }
148 
pata_bk3710_setpiomode(void __iomem * base,struct ata_device * pair,unsigned int dev,unsigned int cycletime,unsigned int mode)149 static void pata_bk3710_setpiomode(void __iomem *base, struct ata_device *pair,
150 				   unsigned int dev, unsigned int cycletime,
151 				   unsigned int mode)
152 {
153 	const struct ata_timing *t;
154 	u32 val32;
155 	u8 t2, t2i, t0;
156 
157 	t = ata_timing_find_mode(XFER_PIO_0 + mode);
158 
159 	/* PIO Data Setup */
160 	t0 = DIV_ROUND_UP(cycletime, ideclk_period);
161 	t2 = DIV_ROUND_UP(t->active, ideclk_period);
162 
163 	t2i = t0 - t2 - 1;
164 	t2--;
165 
166 	val32 = ioread32(base + BK3710_DATSTB) & (0xFF << (dev ? 0 : 8));
167 	val32 |= t2 << (dev ? 8 : 0);
168 	iowrite32(val32, base + BK3710_DATSTB);
169 
170 	val32 = ioread32(base + BK3710_DATRCVR) & (0xFF << (dev ? 0 : 8));
171 	val32 |= t2i << (dev ? 8 : 0);
172 	iowrite32(val32, base + BK3710_DATRCVR);
173 
174 	/* FIXME: this is broken also in the old driver */
175 	if (pair) {
176 		u8 mode2 = pair->pio_mode - XFER_PIO_0;
177 
178 		if (mode2 < mode)
179 			mode = mode2;
180 	}
181 
182 	/* TASKFILE Setup */
183 	t0 = DIV_ROUND_UP(t->cyc8b, ideclk_period);
184 	t2 = DIV_ROUND_UP(t->act8b, ideclk_period);
185 
186 	t2i = t0 - t2 - 1;
187 	t2--;
188 
189 	val32 = ioread32(base + BK3710_REGSTB) & (0xFF << (dev ? 0 : 8));
190 	val32 |= t2 << (dev ? 8 : 0);
191 	iowrite32(val32, base + BK3710_REGSTB);
192 
193 	val32 = ioread32(base + BK3710_REGRCVR) & (0xFF << (dev ? 0 : 8));
194 	val32 |= t2i << (dev ? 8 : 0);
195 	iowrite32(val32, base + BK3710_REGRCVR);
196 }
197 
pata_bk3710_set_piomode(struct ata_port * ap,struct ata_device * adev)198 static void pata_bk3710_set_piomode(struct ata_port *ap,
199 				    struct ata_device *adev)
200 {
201 	void __iomem *base = (void __iomem *)ap->ioaddr.bmdma_addr;
202 	struct ata_device *pair = ata_dev_pair(adev);
203 	const struct ata_timing *t = ata_timing_find_mode(adev->pio_mode);
204 	const u16 *id = adev->id;
205 	unsigned int cycle_time = 0;
206 	int is_slave = adev->devno;
207 	const u8 pio = adev->pio_mode - XFER_PIO_0;
208 
209 	if (id[ATA_ID_FIELD_VALID] & 2) {
210 		if (ata_id_has_iordy(id))
211 			cycle_time = id[ATA_ID_EIDE_PIO_IORDY];
212 		else
213 			cycle_time = id[ATA_ID_EIDE_PIO];
214 
215 		/* conservative "downgrade" for all pre-ATA2 drives */
216 		if (pio < 3 && cycle_time < t->cycle)
217 			cycle_time = 0; /* use standard timing */
218 	}
219 
220 	if (!cycle_time)
221 		cycle_time = t->cycle;
222 
223 	pata_bk3710_setpiomode(base, pair, is_slave, cycle_time, pio);
224 }
225 
pata_bk3710_chipinit(void __iomem * base)226 static void pata_bk3710_chipinit(void __iomem *base)
227 {
228 	/*
229 	 * REVISIT:  the ATA reset signal needs to be managed through a
230 	 * GPIO, which means it should come from platform_data.  Until
231 	 * we get and use such information, we have to trust that things
232 	 * have been reset before we get here.
233 	 */
234 
235 	/*
236 	 * Program the IDETIMP Register Value based on the following assumptions
237 	 *
238 	 * (ATA_IDETIMP_IDEEN		, ENABLE ) |
239 	 * (ATA_IDETIMP_PREPOST1	, DISABLE) |
240 	 * (ATA_IDETIMP_PREPOST0	, DISABLE) |
241 	 *
242 	 * DM6446 silicon rev 2.1 and earlier have no observed net benefit
243 	 * from enabling prefetch/postwrite.
244 	 */
245 	iowrite16(BIT(15), base + BK3710_IDETIMP);
246 
247 	/*
248 	 * UDMACTL Ultra-ATA DMA Control
249 	 * (ATA_UDMACTL_UDMAP1	, 0 ) |
250 	 * (ATA_UDMACTL_UDMAP0	, 0 )
251 	 *
252 	 */
253 	iowrite16(0, base + BK3710_UDMACTL);
254 
255 	/*
256 	 * MISCCTL Miscellaneous Conrol Register
257 	 * (ATA_MISCCTL_HWNHLD1P	, 1 cycle)
258 	 * (ATA_MISCCTL_HWNHLD0P	, 1 cycle)
259 	 * (ATA_MISCCTL_TIMORIDE	, 1)
260 	 */
261 	iowrite32(0x001, base + BK3710_MISCCTL);
262 
263 	/*
264 	 * IORDYTMP IORDY Timer for Primary Register
265 	 * (ATA_IORDYTMP_IORDYTMP	, DISABLE)
266 	 */
267 	iowrite32(0, base + BK3710_IORDYTMP);
268 
269 	/*
270 	 * Configure BMISP Register
271 	 * (ATA_BMISP_DMAEN1	, DISABLE )	|
272 	 * (ATA_BMISP_DMAEN0	, DISABLE )	|
273 	 * (ATA_BMISP_IORDYINT	, CLEAR)	|
274 	 * (ATA_BMISP_INTRSTAT	, CLEAR)	|
275 	 * (ATA_BMISP_DMAERROR	, CLEAR)
276 	 */
277 	iowrite16(0xE, base + BK3710_BMISP);
278 
279 	pata_bk3710_setpiomode(base, NULL, 0, 600, 0);
280 	pata_bk3710_setpiomode(base, NULL, 1, 600, 0);
281 }
282 
283 static struct ata_port_operations pata_bk3710_ports_ops = {
284 	.inherits		= &ata_bmdma_port_ops,
285 	.cable_detect		= ata_cable_80wire,
286 
287 	.set_piomode		= pata_bk3710_set_piomode,
288 	.set_dmamode		= pata_bk3710_set_dmamode,
289 };
290 
pata_bk3710_probe(struct platform_device * pdev)291 static int __init pata_bk3710_probe(struct platform_device *pdev)
292 {
293 	struct clk *clk;
294 	struct resource *mem;
295 	struct ata_host *host;
296 	struct ata_port *ap;
297 	void __iomem *base;
298 	unsigned long rate;
299 	int irq;
300 
301 	clk = devm_clk_get(&pdev->dev, NULL);
302 	if (IS_ERR(clk))
303 		return -ENODEV;
304 
305 	clk_enable(clk);
306 	rate = clk_get_rate(clk);
307 	if (!rate)
308 		return -EINVAL;
309 
310 	/* NOTE:  round *down* to meet minimum timings; we count in clocks */
311 	ideclk_period = 1000000000UL / rate;
312 
313 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
314 
315 	irq = platform_get_irq(pdev, 0);
316 	if (irq < 0) {
317 		pr_err(DRV_NAME ": failed to get IRQ resource\n");
318 		return irq;
319 	}
320 
321 	base = devm_ioremap_resource(&pdev->dev, mem);
322 	if (IS_ERR(base))
323 		return PTR_ERR(base);
324 
325 	/* configure the Palmchip controller */
326 	pata_bk3710_chipinit(base);
327 
328 	/* allocate host */
329 	host = ata_host_alloc(&pdev->dev, 1);
330 	if (!host)
331 		return -ENOMEM;
332 	ap = host->ports[0];
333 
334 	ap->ops = &pata_bk3710_ports_ops;
335 	ap->pio_mask = ATA_PIO4;
336 	ap->mwdma_mask = ATA_MWDMA2;
337 	ap->udma_mask = rate < 100000000 ? ATA_UDMA4 : ATA_UDMA5;
338 	ap->flags |= ATA_FLAG_SLAVE_POSS;
339 
340 	ap->ioaddr.data_addr		= base + BK3710_TF_OFFSET;
341 	ap->ioaddr.error_addr		= base + BK3710_TF_OFFSET + 1;
342 	ap->ioaddr.feature_addr		= base + BK3710_TF_OFFSET + 1;
343 	ap->ioaddr.nsect_addr		= base + BK3710_TF_OFFSET + 2;
344 	ap->ioaddr.lbal_addr		= base + BK3710_TF_OFFSET + 3;
345 	ap->ioaddr.lbam_addr		= base + BK3710_TF_OFFSET + 4;
346 	ap->ioaddr.lbah_addr		= base + BK3710_TF_OFFSET + 5;
347 	ap->ioaddr.device_addr		= base + BK3710_TF_OFFSET + 6;
348 	ap->ioaddr.status_addr		= base + BK3710_TF_OFFSET + 7;
349 	ap->ioaddr.command_addr		= base + BK3710_TF_OFFSET + 7;
350 
351 	ap->ioaddr.altstatus_addr	= base + BK3710_CTL_OFFSET;
352 	ap->ioaddr.ctl_addr		= base + BK3710_CTL_OFFSET;
353 
354 	ap->ioaddr.bmdma_addr		= base;
355 
356 	ata_port_desc(ap, "cmd 0x%lx ctl 0x%lx",
357 		      (unsigned long)base + BK3710_TF_OFFSET,
358 		      (unsigned long)base + BK3710_CTL_OFFSET);
359 
360 	/* activate */
361 	return ata_host_activate(host, irq, ata_sff_interrupt, 0,
362 				 &pata_bk3710_sht);
363 }
364 
365 /* work with hotplug and coldplug */
366 MODULE_ALIAS("platform:palm_bk3710");
367 
368 static struct platform_driver pata_bk3710_driver = {
369 	.driver = {
370 		.name = "palm_bk3710",
371 	},
372 };
373 
pata_bk3710_init(void)374 static int __init pata_bk3710_init(void)
375 {
376 	return platform_driver_probe(&pata_bk3710_driver, pata_bk3710_probe);
377 }
378 
379 module_init(pata_bk3710_init);
380 MODULE_LICENSE("GPL v2");
381