1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * New ATA layer SC1200 driver Alan Cox <alan@lxorguk.ukuu.org.uk>
4 *
5 * TODO: Mode selection filtering
6 * TODO: Needs custom DMA cleanup code
7 *
8 * Based very heavily on
9 *
10 * linux/drivers/ide/pci/sc1200.c Version 0.91 28-Jan-2003
11 *
12 * Copyright (C) 2000-2002 Mark Lord <mlord@pobox.com>
13 * May be copied or modified under the terms of the GNU General Public License
14 *
15 * Development of this chipset driver was funded
16 * by the nice folks at National Semiconductor.
17 */
18
19 #include <linux/kernel.h>
20 #include <linux/module.h>
21 #include <linux/pci.h>
22 #include <linux/blkdev.h>
23 #include <linux/delay.h>
24 #include <scsi/scsi_host.h>
25 #include <linux/libata.h>
26
27 #define DRV_NAME "pata_sc1200"
28 #define DRV_VERSION "0.2.6"
29
30 #define SC1200_REV_A 0x00
31 #define SC1200_REV_B1 0x01
32 #define SC1200_REV_B3 0x02
33 #define SC1200_REV_C1 0x03
34 #define SC1200_REV_D1 0x04
35
36 /**
37 * sc1200_clock - PCI clock
38 *
39 * Return the PCI bus clocking for the SC1200 chipset configuration
40 * in use. We return 0 for 33MHz 1 for 48MHz and 2 for 66Mhz
41 */
42
sc1200_clock(void)43 static int sc1200_clock(void)
44 {
45 /* Magic registers that give us the chipset data */
46 u8 chip_id = inb(0x903C);
47 u8 silicon_rev = inb(0x903D);
48 u16 pci_clock;
49
50 if (chip_id == 0x04 && silicon_rev < SC1200_REV_B1)
51 return 0; /* 33 MHz mode */
52
53 /* Clock generator configuration 0x901E its 8/9 are the PCI clocking
54 0/3 is 33Mhz 1 is 48 2 is 66 */
55
56 pci_clock = inw(0x901E);
57 pci_clock >>= 8;
58 pci_clock &= 0x03;
59 if (pci_clock == 3)
60 pci_clock = 0;
61 return pci_clock;
62 }
63
64 /**
65 * sc1200_set_piomode - PIO setup
66 * @ap: ATA interface
67 * @adev: device on the interface
68 *
69 * Set our PIO requirements. This is fairly simple on the SC1200
70 */
71
sc1200_set_piomode(struct ata_port * ap,struct ata_device * adev)72 static void sc1200_set_piomode(struct ata_port *ap, struct ata_device *adev)
73 {
74 static const u32 pio_timings[4][5] = {
75 /* format0, 33Mhz */
76 { 0x00009172, 0x00012171, 0x00020080, 0x00032010, 0x00040010 },
77 /* format1, 33Mhz */
78 { 0xd1329172, 0x71212171, 0x30200080, 0x20102010, 0x00100010 },
79 /* format1, 48Mhz */
80 { 0xfaa3f4f3, 0xc23232b2, 0x513101c1, 0x31213121, 0x10211021 },
81 /* format1, 66Mhz */
82 { 0xfff4fff4, 0xf35353d3, 0x814102f1, 0x42314231, 0x11311131 }
83 };
84
85 struct pci_dev *pdev = to_pci_dev(ap->host->dev);
86 u32 format;
87 unsigned int reg = 0x40 + 0x10 * ap->port_no;
88 int mode = adev->pio_mode - XFER_PIO_0;
89
90 pci_read_config_dword(pdev, reg + 4, &format);
91 format >>= 31;
92 format += sc1200_clock();
93 pci_write_config_dword(pdev, reg + 8 * adev->devno,
94 pio_timings[format][mode]);
95 }
96
97 /**
98 * sc1200_set_dmamode - DMA timing setup
99 * @ap: ATA interface
100 * @adev: Device being configured
101 *
102 * We cannot mix MWDMA and UDMA without reloading timings each switch
103 * master to slave.
104 */
105
sc1200_set_dmamode(struct ata_port * ap,struct ata_device * adev)106 static void sc1200_set_dmamode(struct ata_port *ap, struct ata_device *adev)
107 {
108 static const u32 udma_timing[3][3] = {
109 { 0x00921250, 0x00911140, 0x00911030 },
110 { 0x00932470, 0x00922260, 0x00922140 },
111 { 0x009436A1, 0x00933481, 0x00923261 }
112 };
113
114 static const u32 mwdma_timing[3][3] = {
115 { 0x00077771, 0x00012121, 0x00002020 },
116 { 0x000BBBB2, 0x00024241, 0x00013131 },
117 { 0x000FFFF3, 0x00035352, 0x00015151 }
118 };
119
120 int clock = sc1200_clock();
121 struct pci_dev *pdev = to_pci_dev(ap->host->dev);
122 unsigned int reg = 0x40 + 0x10 * ap->port_no;
123 int mode = adev->dma_mode;
124 u32 format;
125
126 if (mode >= XFER_UDMA_0)
127 format = udma_timing[clock][mode - XFER_UDMA_0];
128 else
129 format = mwdma_timing[clock][mode - XFER_MW_DMA_0];
130
131 if (adev->devno == 0) {
132 u32 timings;
133
134 pci_read_config_dword(pdev, reg + 4, &timings);
135 timings &= 0x80000000UL;
136 timings |= format;
137 pci_write_config_dword(pdev, reg + 4, timings);
138 } else
139 pci_write_config_dword(pdev, reg + 12, format);
140 }
141
142 /**
143 * sc1200_qc_issue - command issue
144 * @qc: command pending
145 *
146 * Called when the libata layer is about to issue a command. We wrap
147 * this interface so that we can load the correct ATA timings if
148 * necessary. Specifically we have a problem that there is only
149 * one MWDMA/UDMA bit.
150 */
151
sc1200_qc_issue(struct ata_queued_cmd * qc)152 static unsigned int sc1200_qc_issue(struct ata_queued_cmd *qc)
153 {
154 struct ata_port *ap = qc->ap;
155 struct ata_device *adev = qc->dev;
156 struct ata_device *prev = ap->private_data;
157
158 /* See if the DMA settings could be wrong */
159 if (ata_dma_enabled(adev) && adev != prev && prev != NULL) {
160 /* Maybe, but do the channels match MWDMA/UDMA ? */
161 if ((ata_using_udma(adev) && !ata_using_udma(prev)) ||
162 (ata_using_udma(prev) && !ata_using_udma(adev)))
163 /* Switch the mode bits */
164 sc1200_set_dmamode(ap, adev);
165 }
166
167 return ata_bmdma_qc_issue(qc);
168 }
169
170 /**
171 * sc1200_qc_defer - implement serialization
172 * @qc: command
173 *
174 * Serialize command issue on this controller.
175 */
176
sc1200_qc_defer(struct ata_queued_cmd * qc)177 static int sc1200_qc_defer(struct ata_queued_cmd *qc)
178 {
179 struct ata_host *host = qc->ap->host;
180 struct ata_port *alt = host->ports[1 ^ qc->ap->port_no];
181 int rc;
182
183 /* First apply the usual rules */
184 rc = ata_std_qc_defer(qc);
185 if (rc != 0)
186 return rc;
187
188 /* Now apply serialization rules. Only allow a command if the
189 other channel state machine is idle */
190 if (alt && alt->qc_active)
191 return ATA_DEFER_PORT;
192 return 0;
193 }
194
195 static const struct scsi_host_template sc1200_sht = {
196 ATA_BASE_SHT(DRV_NAME),
197 .sg_tablesize = LIBATA_DUMB_MAX_PRD,
198 .dma_boundary = ATA_DMA_BOUNDARY,
199 };
200
201 static struct ata_port_operations sc1200_port_ops = {
202 .inherits = &ata_bmdma_port_ops,
203 .qc_prep = ata_bmdma_dumb_qc_prep,
204 .qc_issue = sc1200_qc_issue,
205 .qc_defer = sc1200_qc_defer,
206 .cable_detect = ata_cable_40wire,
207 .set_piomode = sc1200_set_piomode,
208 .set_dmamode = sc1200_set_dmamode,
209 };
210
211 /**
212 * sc1200_init_one - Initialise an SC1200
213 * @dev: PCI device
214 * @id: Entry in match table
215 *
216 * Just throw the needed data at the libata helper and it does all
217 * our work.
218 */
219
sc1200_init_one(struct pci_dev * dev,const struct pci_device_id * id)220 static int sc1200_init_one(struct pci_dev *dev, const struct pci_device_id *id)
221 {
222 static const struct ata_port_info info = {
223 .flags = ATA_FLAG_SLAVE_POSS,
224 .pio_mask = ATA_PIO4,
225 .mwdma_mask = ATA_MWDMA2,
226 .udma_mask = ATA_UDMA2,
227 .port_ops = &sc1200_port_ops
228 };
229 const struct ata_port_info *ppi[] = { &info, NULL };
230
231 return ata_pci_bmdma_init_one(dev, ppi, &sc1200_sht, NULL, 0);
232 }
233
234 static const struct pci_device_id sc1200[] = {
235 { PCI_VDEVICE(NS, PCI_DEVICE_ID_NS_SCx200_IDE), },
236
237 { },
238 };
239
240 static struct pci_driver sc1200_pci_driver = {
241 .name = DRV_NAME,
242 .id_table = sc1200,
243 .probe = sc1200_init_one,
244 .remove = ata_pci_remove_one,
245 #ifdef CONFIG_PM_SLEEP
246 .suspend = ata_pci_device_suspend,
247 .resume = ata_pci_device_resume,
248 #endif
249 };
250
251 module_pci_driver(sc1200_pci_driver);
252
253 MODULE_AUTHOR("Alan Cox, Mark Lord");
254 MODULE_DESCRIPTION("low-level driver for the NS/AMD SC1200");
255 MODULE_LICENSE("GPL");
256 MODULE_DEVICE_TABLE(pci, sc1200);
257 MODULE_VERSION(DRV_VERSION);
258