[mirror_ubuntu-focal-kernel.git] / drivers / char / ipmi / ipmi_dmi.c

// SPDX-License-Identifier: GPL-2.0
/*
 * A hack to create a platform device from a DMI entry.  This will
 * allow autoloading of the IPMI drive based on SMBIOS entries.
 */

#include <linux/ipmi.h>
#include <linux/init.h>
#include <linux/dmi.h>
#include <linux/platform_device.h>
#include <linux/property.h>
#include "ipmi_dmi.h"

struct ipmi_dmi_info {
	int type;
	u32 flags;
	unsigned long addr;
	u8 slave_addr;
	struct ipmi_dmi_info *next;
};

static struct ipmi_dmi_info *ipmi_dmi_infos;

static int ipmi_dmi_nr __initdata;

static void __init dmi_add_platform_ipmi(unsigned long base_addr,
					 u32 flags,
					 u8 slave_addr,
					 int irq,
					 int offset,
					 int type)
{
	struct platform_device *pdev;
	struct resource r[4];
	unsigned int num_r = 1, size;
	struct property_entry p[4] = {
		PROPERTY_ENTRY_U8("slave-addr", slave_addr),
		PROPERTY_ENTRY_U8("ipmi-type", type),
		PROPERTY_ENTRY_U16("i2c-addr", base_addr),
		{ }
	};
	char *name, *override;
	int rv;
	struct ipmi_dmi_info *info;

	info = kmalloc(sizeof(*info), GFP_KERNEL);
	if (!info) {
		pr_warn("ipmi:dmi: Could not allocate dmi info\n");
	} else {
		info->type = type;
		info->flags = flags;
		info->addr = base_addr;
		info->slave_addr = slave_addr;
		info->next = ipmi_dmi_infos;
		ipmi_dmi_infos = info;
	}

	name = "dmi-ipmi-si";
	override = "ipmi_si";
	switch (type) {
	case IPMI_DMI_TYPE_SSIF:
		name = "dmi-ipmi-ssif";
		override = "ipmi_ssif";
		offset = 1;
		size = 1;
		break;
	case IPMI_DMI_TYPE_BT:
		size = 3;
		break;
	case IPMI_DMI_TYPE_KCS:
	case IPMI_DMI_TYPE_SMIC:
		size = 2;
		break;
	default:
		pr_err("ipmi:dmi: Invalid IPMI type: %d", type);
		return;
	}

	pdev = platform_device_alloc(name, ipmi_dmi_nr);
	if (!pdev) {
		pr_err("ipmi:dmi: Error allocation IPMI platform device");
		return;
	}
	pdev->driver_override = override;

	if (type == IPMI_DMI_TYPE_SSIF)
		goto add_properties;

	memset(r, 0, sizeof(r));

	r[0].start = base_addr;
	r[0].end = r[0].start + offset - 1;
	r[0].name = "IPMI Address 1";
	r[0].flags = flags;

	if (size > 1) {
		r[1].start = r[0].start + offset;
		r[1].end = r[1].start + offset - 1;
		r[1].name = "IPMI Address 2";
		r[1].flags = flags;
		num_r++;
	}

	if (size > 2) {
		r[2].start = r[1].start + offset;
		r[2].end = r[2].start + offset - 1;
		r[2].name = "IPMI Address 3";
		r[2].flags = flags;
		num_r++;
	}

	if (irq) {
		r[num_r].start = irq;
		r[num_r].end = irq;
		r[num_r].name = "IPMI IRQ";
		r[num_r].flags = IORESOURCE_IRQ;
		num_r++;
	}

	rv = platform_device_add_resources(pdev, r, num_r);
	if (rv) {
		dev_err(&pdev->dev,
			"ipmi:dmi: Unable to add resources: %d\n", rv);
		goto err;
	}

add_properties:
	rv = platform_device_add_properties(pdev, p);
	if (rv) {
		dev_err(&pdev->dev,
			"ipmi:dmi: Unable to add properties: %d\n", rv);
		goto err;
	}

	rv = platform_device_add(pdev);
	if (rv) {
		dev_err(&pdev->dev, "ipmi:dmi: Unable to add device: %d\n", rv);
		goto err;
	}

	ipmi_dmi_nr++;
	return;

err:
	platform_device_put(pdev);
}

/*
 * Look up the slave address for a given interface.  This is here
 * because ACPI doesn't have a slave address while SMBIOS does, but we
 * prefer using ACPI so the ACPI code can use the IPMI namespace.
 * This function allows an ACPI-specified IPMI device to look up the
 * slave address from the DMI table.
 */
int ipmi_dmi_get_slave_addr(int type, u32 flags, unsigned long base_addr)
{
	struct ipmi_dmi_info *info = ipmi_dmi_infos;

	while (info) {
		if (info->type == type &&
		    info->flags == flags &&
		    info->addr == base_addr)
			return info->slave_addr;
		info = info->next;
	}

	return 0;
}
EXPORT_SYMBOL(ipmi_dmi_get_slave_addr);

#define DMI_IPMI_MIN_LENGTH	0x10
#define DMI_IPMI_VER2_LENGTH	0x12
#define DMI_IPMI_TYPE		4
#define DMI_IPMI_SLAVEADDR	6
#define DMI_IPMI_ADDR		8
#define DMI_IPMI_ACCESS		0x10
#define DMI_IPMI_IRQ		0x11
#define DMI_IPMI_IO_MASK	0xfffe

static void __init dmi_decode_ipmi(const struct dmi_header *dm)
{
	const u8	*data = (const u8 *) dm;
	u32             flags = IORESOURCE_IO;
	unsigned long	base_addr;
	u8              len = dm->length;
	u8              slave_addr;
	int             irq = 0, offset;
	int             type;

	if (len < DMI_IPMI_MIN_LENGTH)
		return;

	type = data[DMI_IPMI_TYPE];
	slave_addr = data[DMI_IPMI_SLAVEADDR];

	memcpy(&base_addr, data + DMI_IPMI_ADDR, sizeof(unsigned long));
	if (len >= DMI_IPMI_VER2_LENGTH) {
		if (type == IPMI_DMI_TYPE_SSIF) {
			offset = 0;
			flags = 0;
			base_addr = data[DMI_IPMI_ADDR] >> 1;
			if (base_addr == 0) {
				/*
				 * Some broken systems put the I2C address in
				 * the slave address field.  We try to
				 * accommodate them here.
				 */
				base_addr = data[DMI_IPMI_SLAVEADDR] >> 1;
				slave_addr = 0;
			}
		} else {
			if (base_addr & 1) {
				/* I/O */
				base_addr &= DMI_IPMI_IO_MASK;
			} else {
				/* Memory */
				flags = IORESOURCE_MEM;
			}

			/*
			 * If bit 4 of byte 0x10 is set, then the lsb
			 * for the address is odd.
			 */
			base_addr |= (data[DMI_IPMI_ACCESS] >> 4) & 1;

			irq = data[DMI_IPMI_IRQ];

			/*
			 * The top two bits of byte 0x10 hold the
			 * register spacing.
			 */
			switch ((data[DMI_IPMI_ACCESS] >> 6) & 3) {
			case 0: /* Byte boundaries */
				offset = 1;
				break;
			case 1: /* 32-bit boundaries */
				offset = 4;
				break;
			case 2: /* 16-byte boundaries */
				offset = 16;
				break;
			default:
				pr_err("ipmi:dmi: Invalid offset: 0");
				return;
			}
		}
	} else {
		/* Old DMI spec. */
		/*
		 * Note that technically, the lower bit of the base
		 * address should be 1 if the address is I/O and 0 if
		 * the address is in memory.  So many systems get that
		 * wrong (and all that I have seen are I/O) so we just
		 * ignore that bit and assume I/O.  Systems that use
		 * memory should use the newer spec, anyway.
		 */
		base_addr = base_addr & DMI_IPMI_IO_MASK;
		offset = 1;
	}

	dmi_add_platform_ipmi(base_addr, flags, slave_addr, irq,
			      offset, type);
}

static int __init scan_for_dmi_ipmi(void)
{
	const struct dmi_device *dev = NULL;

	while ((dev = dmi_find_device(DMI_DEV_TYPE_IPMI, NULL, dev)))
		dmi_decode_ipmi((const struct dmi_header *) dev->device_data);

	return 0;
}
subsys_initcall(scan_for_dmi_ipmi);
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
9f88145f CM	2	/*
	3	* A hack to create a platform device from a DMI entry. This will
	4	* allow autoloading of the IPMI drive based on SMBIOS entries.
	5	*/
	6
	7	#include <linux/ipmi.h>
	8	#include <linux/init.h>
	9	#include <linux/dmi.h>
	10	#include <linux/platform_device.h>
	11	#include <linux/property.h>
	12	#include "ipmi_dmi.h"
	13
	14	struct ipmi_dmi_info {
	15	int type;
	16	u32 flags;
	17	unsigned long addr;
	18	u8 slave_addr;
	19	struct ipmi_dmi_info *next;
	20	};
	21
	22	static struct ipmi_dmi_info *ipmi_dmi_infos;
	23
	24	static int ipmi_dmi_nr __initdata;
	25
	26	static void __init dmi_add_platform_ipmi(unsigned long base_addr,
	27	u32 flags,
	28	u8 slave_addr,
	29	int irq,
	30	int offset,
	31	int type)
	32	{
	33	struct platform_device *pdev;
	34	struct resource r[4];
	35	unsigned int num_r = 1, size;
	36	struct property_entry p[4] = {
	37	PROPERTY_ENTRY_U8("slave-addr", slave_addr),
	38	PROPERTY_ENTRY_U8("ipmi-type", type),
	39	PROPERTY_ENTRY_U16("i2c-addr", base_addr),
	40	{ }
	41	};
	42	char name, override;
	43	int rv;
	44	struct ipmi_dmi_info *info;
	45
	46	info = kmalloc(sizeof(*info), GFP_KERNEL);
	47	if (!info) {
	48	pr_warn("ipmi:dmi: Could not allocate dmi info\n");
	49	} else {
	50	info->type = type;
	51	info->flags = flags;
	52	info->addr = base_addr;
	53	info->slave_addr = slave_addr;
	54	info->next = ipmi_dmi_infos;
	55	ipmi_dmi_infos = info;
	56	}
	57
	58	name = "dmi-ipmi-si";
	59	override = "ipmi_si";
	60	switch (type) {
	61	case IPMI_DMI_TYPE_SSIF:
	62	name = "dmi-ipmi-ssif";
	63	override = "ipmi_ssif";
	64	offset = 1;
	65	size = 1;
66	break;
67	case IPMI_DMI_TYPE_BT:
68	size = 3;
69	break;
70	case IPMI_DMI_TYPE_KCS:
71	case IPMI_DMI_TYPE_SMIC:
72	size = 2;
73	break;
74	default:
75	pr_err("ipmi:dmi: Invalid IPMI type: %d", type);
76	return;
77	}
78
79	pdev = platform_device_alloc(name, ipmi_dmi_nr);
80	if (!pdev) {
81	pr_err("ipmi:dmi: Error allocation IPMI platform device");
82	return;
83	}
84	pdev->driver_override = override;
85
86	if (type == IPMI_DMI_TYPE_SSIF)
87	goto add_properties;
88
89	memset(r, 0, sizeof(r));
90
91	r[0].start = base_addr;
92	r[0].end = r[0].start + offset - 1;
93	r[0].name = "IPMI Address 1";
94	r[0].flags = flags;
95
96	if (size > 1) {
97	r[1].start = r[0].start + offset;
98	r[1].end = r[1].start + offset - 1;
99	r[1].name = "IPMI Address 2";
100	r[1].flags = flags;
101	num_r++;
102	}
103
104	if (size > 2) {
105	r[2].start = r[1].start + offset;
106	r[2].end = r[2].start + offset - 1;
107	r[2].name = "IPMI Address 3";
108	r[2].flags = flags;
109	num_r++;
110	}
111
112	if (irq) {
113	r[num_r].start = irq;
114	r[num_r].end = irq;
115	r[num_r].name = "IPMI IRQ";
116	r[num_r].flags = IORESOURCE_IRQ;
117	num_r++;
118	}
119
120	rv = platform_device_add_resources(pdev, r, num_r);
121	if (rv) {
122	dev_err(&pdev->dev,
123	"ipmi:dmi: Unable to add resources: %d\n", rv);
124	goto err;
125	}
126
127	add_properties:
128	rv = platform_device_add_properties(pdev, p);
129	if (rv) {
130	dev_err(&pdev->dev,
131	"ipmi:dmi: Unable to add properties: %d\n", rv);
132	goto err;
133	}
134
135	rv = platform_device_add(pdev);
136	if (rv) {
137	dev_err(&pdev->dev, "ipmi:dmi: Unable to add device: %d\n", rv);
138	goto err;
139	}
140
141	ipmi_dmi_nr++;
142	return;
143
144	err:
145	platform_device_put(pdev);
146	}
147
148	/*
149	* Look up the slave address for a given interface. This is here
150	* because ACPI doesn't have a slave address while SMBIOS does, but we
151	* prefer using ACPI so the ACPI code can use the IPMI namespace.
152	* This function allows an ACPI-specified IPMI device to look up the
153	* slave address from the DMI table.
154	*/
155	int ipmi_dmi_get_slave_addr(int type, u32 flags, unsigned long base_addr)
156	{
157	struct ipmi_dmi_info *info = ipmi_dmi_infos;
158
159	while (info) {
160	if (info->type == type &&
161	info->flags == flags &&
162	info->addr == base_addr)
163	return info->slave_addr;
164	info = info->next;
165	}
166
167	return 0;
168	}
169	EXPORT_SYMBOL(ipmi_dmi_get_slave_addr);
170
171	#define DMI_IPMI_MIN_LENGTH 0x10
172	#define DMI_IPMI_VER2_LENGTH 0x12
173	#define DMI_IPMI_TYPE 4
174	#define DMI_IPMI_SLAVEADDR 6
175	#define DMI_IPMI_ADDR 8
176	#define DMI_IPMI_ACCESS 0x10
177	#define DMI_IPMI_IRQ 0x11
178	#define DMI_IPMI_IO_MASK 0xfffe
179
180	static void __init dmi_decode_ipmi(const struct dmi_header *dm)
181	{
182	const u8 data = (const u8 ) dm;
183	u32 flags = IORESOURCE_IO;
184	unsigned long base_addr;
185	u8 len = dm->length;
186	u8 slave_addr;
187	int irq = 0, offset;
188	int type;
189
190	if (len < DMI_IPMI_MIN_LENGTH)
191	return;
192
193	type = data[DMI_IPMI_TYPE];
194	slave_addr = data[DMI_IPMI_SLAVEADDR];
195
196	memcpy(&base_addr, data + DMI_IPMI_ADDR, sizeof(unsigned long));
197	if (len >= DMI_IPMI_VER2_LENGTH) {
198	if (type == IPMI_DMI_TYPE_SSIF) {
199	offset = 0;
200	flags = 0;
201	base_addr = data[DMI_IPMI_ADDR] >> 1;
202	if (base_addr == 0) {
203	/*
204	* Some broken systems put the I2C address in
205	* the slave address field. We try to
206	* accommodate them here.
207	*/
208	base_addr = data[DMI_IPMI_SLAVEADDR] >> 1;
209	slave_addr = 0;
210	}
211	} else {
212	if (base_addr & 1) {
213	/* I/O */
214	base_addr &= DMI_IPMI_IO_MASK;
215	} else {
216	/* Memory */
217	flags = IORESOURCE_MEM;
218	}
219
220	/*
221	* If bit 4 of byte 0x10 is set, then the lsb
222	* for the address is odd.
223	*/
224	base_addr \|= (data[DMI_IPMI_ACCESS] >> 4) & 1;
225
226	irq = data[DMI_IPMI_IRQ];
227
228	/*
229	* The top two bits of byte 0x10 hold the
230	* register spacing.
231	*/
232	switch ((data[DMI_IPMI_ACCESS] >> 6) & 3) {
233	case 0: /* Byte boundaries */
234	offset = 1;
235	break;
236	case 1: /* 32-bit boundaries */
237	offset = 4;
238	break;
239	case 2: /* 16-byte boundaries */
240	offset = 16;
241	break;
242	default:
243	pr_err("ipmi:dmi: Invalid offset: 0");
244	return;
245	}
246	}
247	} else {
248	/* Old DMI spec. */
249	/*
250	* Note that technically, the lower bit of the base
251	* address should be 1 if the address is I/O and 0 if
252	* the address is in memory. So many systems get that
253	* wrong (and all that I have seen are I/O) so we just
254	* ignore that bit and assume I/O. Systems that use
255	* memory should use the newer spec, anyway.
256	*/
257	base_addr = base_addr & DMI_IPMI_IO_MASK;
258	offset = 1;
259	}
260
261	dmi_add_platform_ipmi(base_addr, flags, slave_addr, irq,
262	offset, type);
263	}
264
265	static int __init scan_for_dmi_ipmi(void)
266	{
267	const struct dmi_device *dev = NULL;
268
269	while ((dev = dmi_find_device(DMI_DEV_TYPE_IPMI, NULL, dev)))
270	dmi_decode_ipmi((const struct dmi_header *) dev->device_data);
271
272	return 0;
273	}
274	subsys_initcall(scan_for_dmi_ipmi);