1#include <linux/types.h>
  2#include <linux/string.h>
  3#include <linux/kernel.h>
  4#include <linux/export.h>
  5#include <linux/interrupt.h>
  6#include <linux/ide.h>
  7#include <linux/bitops.h>
  8
  9static const char *udma_str[] =
 10	 { "UDMA/16", "UDMA/25",  "UDMA/33",  "UDMA/44",
 11	   "UDMA/66", "UDMA/100", "UDMA/133", "UDMA7" };
 12static const char *mwdma_str[] =
 13	{ "MWDMA0", "MWDMA1", "MWDMA2", "MWDMA3", "MWDMA4" };
 14static const char *swdma_str[] =
 15	{ "SWDMA0", "SWDMA1", "SWDMA2" };
 16static const char *pio_str[] =
 17	{ "PIO0", "PIO1", "PIO2", "PIO3", "PIO4", "PIO5", "PIO6" };
 18
 19/**
 20 *	ide_xfer_verbose	-	return IDE mode names
 21 *	@mode: transfer mode
 22 *
 23 *	Returns a constant string giving the name of the mode
 24 *	requested.
 25 */
 26
 27const char *ide_xfer_verbose(u8 mode)
 28{
 29	const char *s;
 30	u8 i = mode & 0xf;
 31
 32	if (mode >= XFER_UDMA_0 && mode <= XFER_UDMA_7)
 33		s = udma_str[i];
 34	else if (mode >= XFER_MW_DMA_0 && mode <= XFER_MW_DMA_4)
 35		s = mwdma_str[i];
 36	else if (mode >= XFER_SW_DMA_0 && mode <= XFER_SW_DMA_2)
 37		s = swdma_str[i];
 38	else if (mode >= XFER_PIO_0 && mode <= XFER_PIO_6)
 39		s = pio_str[i & 0x7];
 40	else if (mode == XFER_PIO_SLOW)
 41		s = "PIO SLOW";
 42	else
 43		s = "XFER ERROR";
 44
 45	return s;
 46}
 47EXPORT_SYMBOL(ide_xfer_verbose);
 48
 49/**
 50 *	ide_get_best_pio_mode	-	get PIO mode from drive
 51 *	@drive: drive to consider
 52 *	@mode_wanted: preferred mode
 53 *	@max_mode: highest allowed mode
 54 *
 55 *	This routine returns the recommended PIO settings for a given drive,
 56 *	based on the drive->id information and the ide_pio_blacklist[].
 57 *
 58 *	Drive PIO mode is auto-selected if 255 is passed as mode_wanted.
 59 *	This is used by most chipset support modules when "auto-tuning".
 60 */
 61
 62static u8 ide_get_best_pio_mode(ide_drive_t *drive, u8 mode_wanted, u8 max_mode)
 63{
 64	u16 *id = drive->id;
 65	int pio_mode = -1, overridden = 0;
 66
 67	if (mode_wanted != 255)
 68		return min_t(u8, mode_wanted, max_mode);
 69
 70	if ((drive->hwif->host_flags & IDE_HFLAG_PIO_NO_BLACKLIST) == 0)
 71		pio_mode = ide_scan_pio_blacklist((char *)&id[ATA_ID_PROD]);
 72
 73	if (pio_mode != -1) {
 74		printk(KERN_INFO "%s: is on PIO blacklist\n", drive->name);
 75	} else {
 76		pio_mode = id[ATA_ID_OLD_PIO_MODES] >> 8;
 77		if (pio_mode > 2) {	/* 2 is maximum allowed tPIO value */
 78			pio_mode = 2;
 79			overridden = 1;
 80		}
 81
 82		if (id[ATA_ID_FIELD_VALID] & 2) {	      /* ATA2? */
 83			if (ata_id_is_cfa(id) && (id[ATA_ID_CFA_MODES] & 7))
 84				pio_mode = 4 + min_t(int, 2,
 85						     id[ATA_ID_CFA_MODES] & 7);
 86			else if (ata_id_has_iordy(id)) {
 87				if (id[ATA_ID_PIO_MODES] & 7) {
 88					overridden = 0;
 89					if (id[ATA_ID_PIO_MODES] & 4)
 90						pio_mode = 5;
 91					else if (id[ATA_ID_PIO_MODES] & 2)
 92						pio_mode = 4;
 93					else
 94						pio_mode = 3;
 95				}
 96			}
 97		}
 98
 99		if (overridden)
100			printk(KERN_INFO "%s: tPIO > 2, assuming tPIO = 2\n",
101					 drive->name);
102	}
103
104	if (pio_mode > max_mode)
105		pio_mode = max_mode;
106
107	return pio_mode;
108}
109
110int ide_pio_need_iordy(ide_drive_t *drive, const u8 pio)
111{
112	/*
113	 * IORDY may lead to controller lock up on certain controllers
114	 * if the port is not occupied.
115	 */
116	if (pio == 0 && (drive->hwif->port_flags & IDE_PFLAG_PROBING))
117		return 0;
118	return ata_id_pio_need_iordy(drive->id, pio);
119}
120EXPORT_SYMBOL_GPL(ide_pio_need_iordy);
121
122int ide_set_pio_mode(ide_drive_t *drive, const u8 mode)
123{
124	ide_hwif_t *hwif = drive->hwif;
125	const struct ide_port_ops *port_ops = hwif->port_ops;
126
127	if (hwif->host_flags & IDE_HFLAG_NO_SET_MODE)
128		return 0;
129
130	if (port_ops == NULL || port_ops->set_pio_mode == NULL)
131		return -1;
132
133	/*
134	 * TODO: temporary hack for some legacy host drivers that didn't
135	 * set transfer mode on the device in ->set_pio_mode method...
136	 */
137	if (port_ops->set_dma_mode == NULL) {
138		drive->pio_mode = mode;
139		port_ops->set_pio_mode(hwif, drive);
140		return 0;
141	}
142
143	if (hwif->host_flags & IDE_HFLAG_POST_SET_MODE) {
144		if (ide_config_drive_speed(drive, mode))
145			return -1;
146		drive->pio_mode = mode;
147		port_ops->set_pio_mode(hwif, drive);
148		return 0;
149	} else {
150		drive->pio_mode = mode;
151		port_ops->set_pio_mode(hwif, drive);
152		return ide_config_drive_speed(drive, mode);
153	}
154}
155
156int ide_set_dma_mode(ide_drive_t *drive, const u8 mode)
157{
158	ide_hwif_t *hwif = drive->hwif;
159	const struct ide_port_ops *port_ops = hwif->port_ops;
160
161	if (hwif->host_flags & IDE_HFLAG_NO_SET_MODE)
162		return 0;
163
164	if (port_ops == NULL || port_ops->set_dma_mode == NULL)
165		return -1;
166
167	if (hwif->host_flags & IDE_HFLAG_POST_SET_MODE) {
168		if (ide_config_drive_speed(drive, mode))
169			return -1;
170		drive->dma_mode = mode;
171		port_ops->set_dma_mode(hwif, drive);
172		return 0;
173	} else {
174		drive->dma_mode = mode;
175		port_ops->set_dma_mode(hwif, drive);
176		return ide_config_drive_speed(drive, mode);
177	}
178}
179EXPORT_SYMBOL_GPL(ide_set_dma_mode);
180
181/* req_pio == "255" for auto-tune */
182void ide_set_pio(ide_drive_t *drive, u8 req_pio)
183{
184	ide_hwif_t *hwif = drive->hwif;
185	const struct ide_port_ops *port_ops = hwif->port_ops;
186	u8 host_pio, pio;
187
188	if (port_ops == NULL || port_ops->set_pio_mode == NULL ||
189	    (hwif->host_flags & IDE_HFLAG_NO_SET_MODE))
190		return;
191
192	BUG_ON(hwif->pio_mask == 0x00);
193
194	host_pio = fls(hwif->pio_mask) - 1;
195
196	pio = ide_get_best_pio_mode(drive, req_pio, host_pio);
197
198	/*
199	 * TODO:
200	 * - report device max PIO mode
201	 * - check req_pio != 255 against device max PIO mode
202	 */
203	printk(KERN_DEBUG "%s: host max PIO%d wanted PIO%d%s selected PIO%d\n",
204			  drive->name, host_pio, req_pio,
205			  req_pio == 255 ? "(auto-tune)" : "", pio);
206
207	(void)ide_set_pio_mode(drive, XFER_PIO_0 + pio);
208}
209EXPORT_SYMBOL_GPL(ide_set_pio);
210
211/**
212 *	ide_rate_filter		-	filter transfer mode
213 *	@drive: IDE device
214 *	@speed: desired speed
215 *
216 *	Given the available transfer modes this function returns
217 *	the best available speed at or below the speed requested.
218 *
219 *	TODO: check device PIO capabilities
220 */
221
222static u8 ide_rate_filter(ide_drive_t *drive, u8 speed)
223{
224	ide_hwif_t *hwif = drive->hwif;
225	u8 mode = ide_find_dma_mode(drive, speed);
226
227	if (mode == 0) {
228		if (hwif->pio_mask)
229			mode = fls(hwif->pio_mask) - 1 + XFER_PIO_0;
230		else
231			mode = XFER_PIO_4;
232	}
233
234/*	printk("%s: mode 0x%02x, speed 0x%02x\n", __func__, mode, speed); */
235
236	return min(speed, mode);
237}
238
239/**
240 *	ide_set_xfer_rate	-	set transfer rate
241 *	@drive: drive to set
242 *	@rate: speed to attempt to set
243 *
244 *	General helper for setting the speed of an IDE device. This
245 *	function knows about user enforced limits from the configuration
246 *	which ->set_pio_mode/->set_dma_mode does not.
247 */
248
249int ide_set_xfer_rate(ide_drive_t *drive, u8 rate)
250{
251	ide_hwif_t *hwif = drive->hwif;
252	const struct ide_port_ops *port_ops = hwif->port_ops;
253
254	if (port_ops == NULL || port_ops->set_dma_mode == NULL ||
255	    (hwif->host_flags & IDE_HFLAG_NO_SET_MODE))
256		return -1;
257
258	rate = ide_rate_filter(drive, rate);
259
260	BUG_ON(rate < XFER_PIO_0);
261
262	if (rate >= XFER_PIO_0 && rate <= XFER_PIO_6)
263		return ide_set_pio_mode(drive, rate);
264
265	return ide_set_dma_mode(drive, rate);
266}