xref: /openbmc/linux/arch/x86/platform/scx200/scx200_32.c (revision 58e16d792a6a8c6b750f637a4649967fcac853dc)
1  // SPDX-License-Identifier: GPL-2.0-only
2  /*
3   *  Copyright (c) 2001,2002 Christer Weinigel <wingel@nano-system.com>
4   *
5   *  National Semiconductor SCx200 support.
6   */
7  
8  #include <linux/module.h>
9  #include <linux/errno.h>
10  #include <linux/kernel.h>
11  #include <linux/init.h>
12  #include <linux/mutex.h>
13  #include <linux/pci.h>
14  
15  #include <linux/scx200.h>
16  #include <linux/scx200_gpio.h>
17  
18  /* Verify that the configuration block really is there */
19  #define scx200_cb_probe(base) (inw((base) + SCx200_CBA) == (base))
20  
21  MODULE_AUTHOR("Christer Weinigel <wingel@nano-system.com>");
22  MODULE_DESCRIPTION("NatSemi SCx200 Driver");
23  MODULE_LICENSE("GPL");
24  
25  unsigned scx200_gpio_base = 0;
26  unsigned long scx200_gpio_shadow[2];
27  
28  unsigned scx200_cb_base = 0;
29  
30  static struct pci_device_id scx200_tbl[] = {
31  	{ PCI_VDEVICE(NS, PCI_DEVICE_ID_NS_SCx200_BRIDGE) },
32  	{ PCI_VDEVICE(NS, PCI_DEVICE_ID_NS_SC1100_BRIDGE) },
33  	{ PCI_VDEVICE(NS, PCI_DEVICE_ID_NS_SCx200_XBUS)   },
34  	{ PCI_VDEVICE(NS, PCI_DEVICE_ID_NS_SC1100_XBUS)   },
35  	{ },
36  };
37  MODULE_DEVICE_TABLE(pci,scx200_tbl);
38  
39  static int scx200_probe(struct pci_dev *, const struct pci_device_id *);
40  
41  static struct pci_driver scx200_pci_driver = {
42  	.name = "scx200",
43  	.id_table = scx200_tbl,
44  	.probe = scx200_probe,
45  };
46  
47  static DEFINE_MUTEX(scx200_gpio_config_lock);
48  
scx200_init_shadow(void)49  static void scx200_init_shadow(void)
50  {
51  	int bank;
52  
53  	/* read the current values driven on the GPIO signals */
54  	for (bank = 0; bank < 2; ++bank)
55  		scx200_gpio_shadow[bank] = inl(scx200_gpio_base + 0x10 * bank);
56  }
57  
scx200_probe(struct pci_dev * pdev,const struct pci_device_id * ent)58  static int scx200_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
59  {
60  	unsigned base;
61  
62  	if (pdev->device == PCI_DEVICE_ID_NS_SCx200_BRIDGE ||
63  	    pdev->device == PCI_DEVICE_ID_NS_SC1100_BRIDGE) {
64  		base = pci_resource_start(pdev, 0);
65  		pr_info("GPIO base 0x%x\n", base);
66  
67  		if (!request_region(base, SCx200_GPIO_SIZE,
68  				    "NatSemi SCx200 GPIO")) {
69  			pr_err("can't allocate I/O for GPIOs\n");
70  			return -EBUSY;
71  		}
72  
73  		scx200_gpio_base = base;
74  		scx200_init_shadow();
75  
76  	} else {
77  		/* find the base of the Configuration Block */
78  		if (scx200_cb_probe(SCx200_CB_BASE_FIXED)) {
79  			scx200_cb_base = SCx200_CB_BASE_FIXED;
80  		} else {
81  			pci_read_config_dword(pdev, SCx200_CBA_SCRATCH, &base);
82  			if (scx200_cb_probe(base)) {
83  				scx200_cb_base = base;
84  			} else {
85  				pr_warn("Configuration Block not found\n");
86  				return -ENODEV;
87  			}
88  		}
89  		pr_info("Configuration Block base 0x%x\n", scx200_cb_base);
90  	}
91  
92  	return 0;
93  }
94  
scx200_gpio_configure(unsigned index,u32 mask,u32 bits)95  u32 scx200_gpio_configure(unsigned index, u32 mask, u32 bits)
96  {
97  	u32 config, new_config;
98  
99  	mutex_lock(&scx200_gpio_config_lock);
100  
101  	outl(index, scx200_gpio_base + 0x20);
102  	config = inl(scx200_gpio_base + 0x24);
103  
104  	new_config = (config & mask) | bits;
105  	outl(new_config, scx200_gpio_base + 0x24);
106  
107  	mutex_unlock(&scx200_gpio_config_lock);
108  
109  	return config;
110  }
111  
scx200_init(void)112  static int __init scx200_init(void)
113  {
114  	pr_info("NatSemi SCx200 Driver\n");
115  	return pci_register_driver(&scx200_pci_driver);
116  }
117  
scx200_cleanup(void)118  static void __exit scx200_cleanup(void)
119  {
120  	pci_unregister_driver(&scx200_pci_driver);
121  	release_region(scx200_gpio_base, SCx200_GPIO_SIZE);
122  }
123  
124  module_init(scx200_init);
125  module_exit(scx200_cleanup);
126  
127  EXPORT_SYMBOL(scx200_gpio_base);
128  EXPORT_SYMBOL(scx200_gpio_shadow);
129  EXPORT_SYMBOL(scx200_gpio_configure);
130  EXPORT_SYMBOL(scx200_cb_base);
131