1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * pata_cmd640.c - CMD640 PCI PATA for new ATA layer
4 * (C) 2007 Red Hat Inc
5 *
6 * Based upon
7 * linux/drivers/ide/pci/cmd640.c Version 1.02 Sep 01, 1996
8 *
9 * Copyright (C) 1995-1996 Linus Torvalds & authors (see driver)
10 *
11 * This drives only the PCI version of the controller. If you have a
12 * VLB one then we have enough docs to support it but you can write
13 * your own code.
14 */
15
16#include <linux/kernel.h>
17#include <linux/module.h>
18#include <linux/pci.h>
19#include <linux/blkdev.h>
20#include <linux/delay.h>
21#include <linux/gfp.h>
22#include <scsi/scsi_host.h>
23#include <linux/libata.h>
24
25#define DRV_NAME "pata_cmd640"
26#define DRV_VERSION "0.0.5"
27
28struct cmd640_reg {
29 int last;
30 u8 reg58[ATA_MAX_DEVICES];
31};
32
33enum {
34 CFR = 0x50,
35 CNTRL = 0x51,
36 CMDTIM = 0x52,
37 ARTIM0 = 0x53,
38 DRWTIM0 = 0x54,
39 ARTIM23 = 0x57,
40 DRWTIM23 = 0x58,
41 BRST = 0x59
42};
43
44/**
45 * cmd640_set_piomode - set initial PIO mode data
46 * @ap: ATA port
47 * @adev: ATA device
48 *
49 * Called to do the PIO mode setup.
50 */
51
52static void cmd640_set_piomode(struct ata_port *ap, struct ata_device *adev)
53{
54 struct cmd640_reg *timing = ap->private_data;
55 struct pci_dev *pdev = to_pci_dev(ap->host->dev);
56 struct ata_timing t;
57 const unsigned long T = 1000000 / 33;
58 const u8 setup_data[] = { 0x40, 0x40, 0x40, 0x80, 0x00 };
59 u8 reg;
60 int arttim = ARTIM0 + 2 * adev->devno;
61 struct ata_device *pair = ata_dev_pair(adev);
62
63 if (ata_timing_compute(adev, adev->pio_mode, &t, T, 0) < 0) {
64 ata_dev_err(adev, DRV_NAME ": mode computation failed.\n");
65 return;
66 }
67
68 /* The second channel has shared timings and the setup timing is
69 messy to switch to merge it for worst case */
70 if (ap->port_no && pair) {
71 struct ata_timing p;
72 ata_timing_compute(pair, pair->pio_mode, &p, T, 1);
73 ata_timing_merge(&p, &t, &t, ATA_TIMING_SETUP);
74 }
75
76 /* Make the timings fit */
77 if (t.recover > 16) {
78 t.active += t.recover - 16;
79 t.recover = 16;
80 }
81 if (t.active > 16)
82 t.active = 16;
83
84 /* Now convert the clocks into values we can actually stuff into
85 the chip */
86
87 if (t.recover > 1)
88 t.recover--; /* 640B only */
89 else
90 t.recover = 15;
91
92 if (t.setup > 4)
93 t.setup = 0xC0;
94 else
95 t.setup = setup_data[t.setup];
96
97 if (ap->port_no == 0) {
98 t.active &= 0x0F; /* 0 = 16 */
99
100 /* Load setup timing */
101 pci_read_config_byte(dev: pdev, where: arttim, val: &reg);
102 reg &= 0x3F;
103 reg |= t.setup;
104 pci_write_config_byte(dev: pdev, where: arttim, val: reg);
105
106 /* Load active/recovery */
107 pci_write_config_byte(dev: pdev, where: arttim + 1, val: (t.active << 4) | t.recover);
108 } else {
109 /* Save the shared timings for channel, they will be loaded
110 by qc_issue. Reloading the setup time is expensive so we
111 keep a merged one loaded */
112 pci_read_config_byte(dev: pdev, where: ARTIM23, val: &reg);
113 reg &= 0x3F;
114 reg |= t.setup;
115 pci_write_config_byte(dev: pdev, where: ARTIM23, val: reg);
116 timing->reg58[adev->devno] = (t.active << 4) | t.recover;
117 }
118}
119
120
121/**
122 * cmd640_qc_issue - command preparation hook
123 * @qc: Command to be issued
124 *
125 * Channel 1 has shared timings. We must reprogram the
126 * clock each drive 2/3 switch we do.
127 */
128
129static unsigned int cmd640_qc_issue(struct ata_queued_cmd *qc)
130{
131 struct ata_port *ap = qc->ap;
132 struct ata_device *adev = qc->dev;
133 struct pci_dev *pdev = to_pci_dev(ap->host->dev);
134 struct cmd640_reg *timing = ap->private_data;
135
136 if (ap->port_no != 0 && adev->devno != timing->last) {
137 pci_write_config_byte(dev: pdev, where: DRWTIM23, val: timing->reg58[adev->devno]);
138 timing->last = adev->devno;
139 }
140 return ata_sff_qc_issue(qc);
141}
142
143/**
144 * cmd640_port_start - port setup
145 * @ap: ATA port being set up
146 *
147 * The CMD640 needs to maintain private data structures so we
148 * allocate space here.
149 */
150
151static int cmd640_port_start(struct ata_port *ap)
152{
153 struct pci_dev *pdev = to_pci_dev(ap->host->dev);
154 struct cmd640_reg *timing;
155
156 timing = devm_kzalloc(dev: &pdev->dev, size: sizeof(struct cmd640_reg), GFP_KERNEL);
157 if (timing == NULL)
158 return -ENOMEM;
159 timing->last = -1; /* Force a load */
160 ap->private_data = timing;
161 return 0;
162}
163
164static bool cmd640_sff_irq_check(struct ata_port *ap)
165{
166 struct pci_dev *pdev = to_pci_dev(ap->host->dev);
167 int irq_reg = ap->port_no ? ARTIM23 : CFR;
168 u8 irq_stat, irq_mask = ap->port_no ? 0x10 : 0x04;
169
170 pci_read_config_byte(dev: pdev, where: irq_reg, val: &irq_stat);
171
172 return irq_stat & irq_mask;
173}
174
175static const struct scsi_host_template cmd640_sht = {
176 ATA_PIO_SHT(DRV_NAME),
177};
178
179static struct ata_port_operations cmd640_port_ops = {
180 .inherits = &ata_sff_port_ops,
181 /* In theory xfer_noirq is not needed once we kill the prefetcher */
182 .sff_data_xfer = ata_sff_data_xfer32,
183 .sff_irq_check = cmd640_sff_irq_check,
184 .qc_issue = cmd640_qc_issue,
185 .cable_detect = ata_cable_40wire,
186 .set_piomode = cmd640_set_piomode,
187 .port_start = cmd640_port_start,
188};
189
190static void cmd640_hardware_init(struct pci_dev *pdev)
191{
192 u8 ctrl;
193
194 /* CMD640 detected, commiserations */
195 pci_write_config_byte(dev: pdev, where: 0x5B, val: 0x00);
196 /* PIO0 command cycles */
197 pci_write_config_byte(dev: pdev, where: CMDTIM, val: 0);
198 /* 512 byte bursts (sector) */
199 pci_write_config_byte(dev: pdev, where: BRST, val: 0x40);
200 /*
201 * A reporter a long time ago
202 * Had problems with the data fifo
203 * So don't run the risk
204 * Of putting crap on the disk
205 * For its better just to go slow
206 */
207 /* Do channel 0 */
208 pci_read_config_byte(dev: pdev, where: CNTRL, val: &ctrl);
209 pci_write_config_byte(dev: pdev, where: CNTRL, val: ctrl | 0xC0);
210 /* Ditto for channel 1 */
211 pci_read_config_byte(dev: pdev, where: ARTIM23, val: &ctrl);
212 ctrl |= 0x0C;
213 pci_write_config_byte(dev: pdev, where: ARTIM23, val: ctrl);
214}
215
216static int cmd640_init_one(struct pci_dev *pdev, const struct pci_device_id *id)
217{
218 static const struct ata_port_info info = {
219 .flags = ATA_FLAG_SLAVE_POSS,
220 .pio_mask = ATA_PIO4,
221 .port_ops = &cmd640_port_ops
222 };
223 const struct ata_port_info *ppi[] = { &info, NULL };
224 int rc;
225
226 rc = pcim_enable_device(pdev);
227 if (rc)
228 return rc;
229
230 cmd640_hardware_init(pdev);
231
232 return ata_pci_sff_init_one(pdev, ppi, sht: &cmd640_sht, NULL, hflags: 0);
233}
234
235#ifdef CONFIG_PM_SLEEP
236static int cmd640_reinit_one(struct pci_dev *pdev)
237{
238 struct ata_host *host = pci_get_drvdata(pdev);
239 int rc;
240
241 rc = ata_pci_device_do_resume(pdev);
242 if (rc)
243 return rc;
244 cmd640_hardware_init(pdev);
245 ata_host_resume(host);
246 return 0;
247}
248#endif
249
250static const struct pci_device_id cmd640[] = {
251 { PCI_VDEVICE(CMD, 0x640), 0 },
252 { },
253};
254
255static struct pci_driver cmd640_pci_driver = {
256 .name = DRV_NAME,
257 .id_table = cmd640,
258 .probe = cmd640_init_one,
259 .remove = ata_pci_remove_one,
260#ifdef CONFIG_PM_SLEEP
261 .suspend = ata_pci_device_suspend,
262 .resume = cmd640_reinit_one,
263#endif
264};
265
266module_pci_driver(cmd640_pci_driver);
267
268MODULE_AUTHOR("Alan Cox");
269MODULE_DESCRIPTION("low-level driver for CMD640 PATA controllers");
270MODULE_LICENSE("GPL");
271MODULE_DEVICE_TABLE(pci, cmd640);
272MODULE_VERSION(DRV_VERSION);
273

source code of linux/drivers/ata/pata_cmd640.c